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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
Journal of Korean Society of Hazard Mitigation
Journal Basic Information
Journal DOI :
Korean Society of Hazard Mitigation
Editor in Chief :
Moo Jong Park
Volume & Issues
Volume 15, Issue 6 - Dec 2015
Volume 15, Issue 5 - Oct 2015
Volume 15, Issue 4 - Aug 2015
Volume 15, Issue 3 - Jun 2015
Volume 15, Issue 2 - Apr 2015
Volume 15, Issue 1 - Feb 2015
Selecting the target year
Reliability Analysis of the Access Door Opening Force Measurement Value of a Pressurized Smoke Control Zone Using an Analog Force Gauge
Lee, Jae-Ou ; Choi, Chung-Seog ;
Journal of Korean Society of Hazard Mitigation, volume 15, issue 3, 2015, Pages 1~6
DOI : 10.9798/KOSHAM.2015.15.3.1
The purpose of this study is to measure an access door opening force of a pressurized smoke control zone and verify the measured value by using an analog force gauge. This study measured the opening force of the access door of the smoke control zone before and after operating the smoke control equipment. The reliability of the opening forces measured by the analog force gauge was verified using the Anderson Darling's statistical analysis method of the Minitab Program. From the fact that all P values of opening force of the access door were less than 0.05 regardless of the operation of the smoke control equipment, the opening force was analyzed to have reliability less than. However, since the of the opening forces of the access doors at all floors shows similar characteristics before and after operating the smoke control equipment, it is analyzed that the accuracy of the measuring device was verified. Therefore, it is thought that major factors for the accurate testing, adjusting and balancing of the pressurized smoke control equipment are accurate calibration of a measuring gauge, correct posture of a measuring person, the same condition of the access doors, etc. In addition, it is thought that human errors can be reduced if the person measuring properly understands the scientific characteristics of the analog force gauge. Therefore, this study proposes that digital and analog force gauges be used together to measure the opening force rather than using only the analog force gauge. It is a scientific approach to reduce errors by performing measurements repeatedly.
The Full-scaled Experimental Study on the Tapered Steel Beam with Non-Compact Web Section
Oh, Myoung Ho ; Kim, Myeong Han ;
Journal of Korean Society of Hazard Mitigation, volume 15, issue 3, 2015, Pages 7~13
DOI : 10.9798/KOSHAM.2015.15.3.7
In this paper was evaluated the applicability of the Korean Building Code (KBC 2013) by performing the full-scaled experiment on the structural strength of the tapered beam with the non-compact web section. The failure mode of the tapered beam in the experiments was determined by the lateral-torsional buckling strength, and the reliability of the optimization design program has been confirmed through the similarity between the analytic and the experimental results. The flexural strength of the tapered beam is probable to be determined according to the equations of the KBC (2013) because the experimental results are very similar to those from the equations of the KBC (2013).
Preventive Measures to Establish the Direction Drawn Through the City Railway Safety Ever Thought Analysis
Kang, Kapseang ; Kim, Sigon ; Kwon, Youngjong ;
Journal of Korean Society of Hazard Mitigation, volume 15, issue 3, 2015, Pages 15~21
DOI : 10.9798/KOSHAM.2015.15.3.15
This research shows the effects of age, gender, drinking, and service hours on an accident on the stairs, deduced from analyzing accident cases provided by urban railway operating agencies. Moreover, types of accident on the stairs were subdivided and each type of risk was also analyzed. And roughly three directions of the establishment of prevention measures were deduced for reducing accidents on the stairs through such investigation. First of all, the establishment of risk-based railway safety management system to which ALARP risk management methodology was applied was suggested. And a method of cost-benefit analysis was then suggested so as to select realistic and rational prevention measures. And lastly, plans of the establishment of the order of priority of prevention measures were suggested in eight-stage procedures in order to decide the order of measures applicable to urban railway station. Such directions of the establishment of prevention measures for reducing accidents are considered to work as a guideline for operating agencies in establishing prevention measures henceforward.
Development of a Low Vibration Rack&Pinion Traction System for More Comfortable Cabin on Mountain Tram
Seo, Sung-il ; Mun, Hyung-suk ; Islam, Abu MD Ariful ;
Journal of Korean Society of Hazard Mitigation, volume 15, issue 3, 2015, Pages 23~26
DOI : 10.9798/KOSHAM.2015.15.3.23
Rack & pinion traction system on mountain tram for climbing steep gradient tracks makes worse the comfortability of cabin because of the vibration generated by gear contact. That is the main reason for complaint of tourists. In this study, to reduce the vibration level of the previous rack&pinion traction system, a low vibration rack&pinion traction system was developed and test models were made so that it could be verified by a wheel-rail contact testing machine. The vibration level induced by the low vibration rack&pinion traction system was 20 times less than that by the conventional rack&pinion traction system. This low vibration rack&pinion traction system can be maintained easily because simple replacement of resilient body is possible. If this resilient rack&pinion traction system is applied to a mountain tram, the vibration and noise level in cabins is reduced drastically so that the comfortability of tourists can be increased.
Improvement of Intelligent Railway Operation System using the Backpropagation Algorithm
Hong, Seon Ho ;
Journal of Korean Society of Hazard Mitigation, volume 15, issue 3, 2015, Pages 27~32
DOI : 10.9798/KOSHAM.2015.15.3.27
Recently, the development of the advanced intelligent systems based on virtual situations and job training has been conducted by several countries of Europe complying cross-country interoperability standards. Thus, Korea Railroad, which will link with the Eurasian railway in the future, must prepare the conversion of current education and training systems based on experience into future systems base on the advanced intelligent operations. To this end, this study investigated the functions of railway operation and the jobs of train drivers required for the development of learning model associated with the artificial neural network theory. In the study, the application of the index task management function based on decision task models was proposed. In addition, the onboard field logical model, which is one of safety barrier of high speed rail system, and the parity model were constituted as case studies of intelligent training models. Then, the effects appling the backpropagation algorithm to these models were checked. Finally, we proposed to extend the need for an intelligent system in accordance with the training needs of systemic administration.
Disaster Risk Evaluation for Urban Areas Under Composite Hazard Factors
Han, Seung Ryong ; Kang, Na Rae ; Lee, Chang Soo ;
Journal of Korean Society of Hazard Mitigation, volume 15, issue 3, 2015, Pages 33~43
DOI : 10.9798/KOSHAM.2015.15.3.33
This paper describes how to develop a disaster risk index for urban areas considering composite hazard factors. The disaster risk is mainly affected by the condition of ground system (e.g. drainage system, flood prevention facilities, etc.) in urban areas as well as strong wind and heavy rain. Therefore, strong wind, heavy rain, and flood are considered as composite hazard factors and strong wind and flood are estimated using simulation methods. In this paper, the disaster risk indices are calculated for each section of Incheon, Korea and compared with each other. The conceptual framework for the disaster risk index is composed of four main factors: disaster hazard, exposure, vulnerability, and emergency response and recovery capability. Each of these four main factors is disaggregated into more specific sub-factors and then indicators. To represent the relative importance of the indicators to each main factor or indicators are calculated by an objective (Principal Component Analysis, PCA) and a subjective (a Delphi method) method simultaneously. Validation of the disaster risk index developed is checked with actual damage data for past 10 years
Flexural Toughness and Material Properties of Steel Fiber Reinforced Very Early Strength Latex Modified Concrete
Park, Jaehoon ; Kim, Yonggon ;
Journal of Korean Society of Hazard Mitigation, volume 15, issue 3, 2015, Pages 45~52
DOI : 10.9798/KOSHAM.2015.15.3.45
The fast track repair using very early strength latex modified concrete(VESLMC) has been used at repair jobs of concrete bridge deck overlay by rephrase for eight (8) to ten (10) hours. A very old damaged bridge could not recover load-carrying capacity by a simple repair work. A reinforcement such as rebar or wire mesh is necessary for strengthening the load carrying capacity of the damaged structure in addition to the simple repair work. However, this additional procedure of one (1) to two (2) hours for reinforcement could impair fast track repair. The purpose of research was to develop a steel fiber reinforced VESLMC (SFR VESLMC) in order to apply at the damaged structure without an additional strengthening procedure. The material properties and flexural toughness of SFR VESLMC were evaluated by testing a series of samples. The results were as follows: The optimized steel fiber content of 30mm long was to be 10% by unit cement content from a series of flexural toughness tests.
Train Operation Regulation of High-Speed Railway Bridge based on Moving Load Analysis during Earthquake
Yun, Ji Hong ; Lee, Hee Young ; Chung, Wonseok ;
Journal of Korean Society of Hazard Mitigation, volume 15, issue 3, 2015, Pages 53~59
DOI : 10.9798/KOSHAM.2015.15.3.53
A large number of researches have been conducted on seismic resistant design of railway bridges. However, research on the running regulation of high-speed train during earthquake is limited. The current running regulation of high-speed train during earthquake was based on the French regulation. Accelerations were measured from the deck rather than ground acceleration, which results in reaching the limit value of the running regulation frequently due to amplified acceleration. This study investigates the dynamic behavior of high-speed railway bridges under earthquake. Analysis results are then compared against dynamic safety criterion in Korean railway design standard and train operation limits of safety instructions on the train operation. It is observed that both dynamic safety and derailment criterion are satisfied when the high-speed train runs over the bridge with the critical speed and under the earthquake level of serviceability limit state.
Recommendation of Adequate Sampling Rate for Drop Weight Impact Test with Application of Nyquist's Sampling Theorem
Lee, Jin Young ; Kim, Dan Bi ; Kwon, Ki yeon ; Yoon, Young soo ;
Journal of Korean Society of Hazard Mitigation, volume 15, issue 3, 2015, Pages 61~67
DOI : 10.9798/KOSHAM.2015.15.3.61
Current concrete structures are quite often exposed to terroristic threats. Therefore, estimating concrete mechanical properties under dynamic loading conditions starts to become important. Due to the high rates of loading and highly dynamic behavior of the specimens, it is hard to be applied the same sampling rates used in common static loading tests to dynamic tests. The objective of this study is to estimate effects of concrete types and applying different impact loads on recommended sampling rates for measuring reaction force and acceleration. The recommended sampling rates in this study were determined according to the Nyquist's sampling theorem. The Nyquist's theorem states that the sampling rate should be at least twice the maximum response frequency(Nyquist frequency) for avoiding aliasing. The results of this study showed the following things: I) the recommended sampling rates for reaction force and acceleration were not influenced by types of concrete and levels of applied impact energy, but the sampling rates was affected by type of measuring data, ii) the recommended sampling rate for acceleration was faster than that for reaction force, so the sampling rate for entire impact test system should be determined based on the sampling rate for acceleration, iii) there was not any relationship between the frequency at the maximum value in power spectrum and the recommended sampling rate.
Structural Behavior of Prestressed Composite Truss Girder Considering Construction Methods
Hong, Yongguk ; Chun, Sungbum ; An, Zuog ;
Journal of Korean Society of Hazard Mitigation, volume 15, issue 3, 2015, Pages 69~74
DOI : 10.9798/KOSHAM.2015.15.3.69
This study focused on comparing the F.C.M(Free Cantilever Method) and combination of the crane method and F.C.M by considering displacement. As a result of this study, F.C.M had the advantage to control the displacement because the displacement of the prestressed composite truss girder using F.C.M is much lower than using it in combination with the crane method. The disadvantage of F.C.M is the diminished quality of welding and safety when the bridge is placed on high elevation. The combination of the crane method displace lower stresses than the F.C.M because F.C.M is a total cantilever structure. But the combination of crane method and F.C.M could create problems such as unbalanced partial moment during pulling up the steel girder(105 m, 250 ton). It could cause serious deformations of the structure. As a result, F.C.M is a better method to build a prestressed composite truss girder.
Risk Analysis Considering the Topography Characteristics of Debris Flow Occurrence Area
Lee, Jun Seon ; Song, Chang Geun ; Kim, Hong Teak ; Lee, Seoung Oh ;
Journal of Korean Society of Hazard Mitigation, volume 15, issue 3, 2015, Pages 75~82
DOI : 10.9798/KOSHAM.2015.15.3.75
Recently, debris flow has occurred so frequently due to abnormal heavy rainfall. Although various studies have been conducted to simulate the topographic behavior of debris flow, geometric effect such as the shapes of slope side has been insufficient. In this study, simulations were conducted with FLO-2D, the commercial software to be recommended by FEMA to simulate debris flow. And target geometries are selected as flatbed, square shape, trapezoidal shape and V-shape. Firstly FLO-2D was verified by the comparison with USGS debris flow experiments (Iverson, 2010). The comparisons showed good agreements in term of the velocity range and the propagation length of debris flows. Furthermore, the concept of HAZUS-HM risk analysis was used to assess the vulnerabilities of the structures by the impact of the debris flow. Simulated results were confirmed debris flow behavior to be changed due to the geometry type. Behavior of debris flows were analyzed according to the maximum depth, velocity, propagation length and vulnerabilities of the structures by the debris flow. This study would be practical to provide quantitatively the spatial distribution of hazard caused by debris flow.
Dynamic Evacuation Path Searching Considering Capacities of Shelters
Son, Youngtae ; Yum, Serye ;
Journal of Korean Society of Hazard Mitigation, volume 15, issue 3, 2015, Pages 83~89
DOI : 10.9798/KOSHAM.2015.15.3.83
In the event of a disaster, most of the current evacuation path search algorithms are based on minimizing the travel cost to each shelters. Since the shelters usually have limited capacities, the vehicle evacuation time may be lengthened to search the alternate shelter if the first chosen shelter is full. A new algorithm is presented in this study which will minimize the vehicle evacuation time by searching a shelter with consideration of its capacity. Link based Dijkstra which is most widely used path search algorithm is utilized and the traffic shall be assigned according to the dynamic transportation network load model. The dynamic network loading model is used to express how a group of vehicles is moving an actual network through the moving cell model that best describes the traffic flow characteristics of the group of vehicles. The suggested algorithm is applied to the example traffic to compare the results where the shelter capacity has been considered in determining the path information and the results where it has not been considered. This study observed and concluded that the total vehicle evacuation time is practically reduced where the shelter capacity has been considered in determining the evacuation path.
Determinants of Process Setting Target Level of Service through the Analysis of Complaints Data caused by Infra Facilities
Park, Miyun ; Kim, Janghee ; Kim, Hyungsu ; Do, Sujeong ; Kim, Seoyun ; Shim, Jaeyeob ;
Journal of Korean Society of Hazard Mitigation, volume 15, issue 3, 2015, Pages 91~98
DOI : 10.9798/KOSHAM.2015.15.3.91
One of the most important requirements in the asset management system of infrastructure facilities is to manage the level of service. After the facilities were built, many parts of the replacement or repair items will be occurred by the requests of the users on the way of operation and management. Many advanced asset management agencies are setting and developing the target service level for managing the quality of service provided by themselves, and also establish annual repair and replacement plan and a long-term plan, based on their target aim. In this study, the complaints related with the sewage of S-area were analyzed, in which is progressed the domestic asset management development for the facilities and pipes related to wastewater. Based on these complaints data, the S-area's service performance of odor, damage and back flow, etc. were analyzed and compared with service level management strategies of advanced asset management agency. Through the steps, response times of complaints having the unclear standards or guidelines developed into the more clearly establishment making the target level of service. The establishment of target LOS will constitute a standard that allows to manage the future service level of S-area.
Shaping the Direction for the Integrated Information Management System for Urban Areas Susceptible to Landslide
Moon, Yonghee ; Lee, Sangeun ;
Journal of Korean Society of Hazard Mitigation, volume 15, issue 3, 2015, Pages 99~106
DOI : 10.9798/KOSHAM.2015.15.3.99
The residential and industrial complex, due to continuing urbanization and industrialization, is adjacent to how steep the damage caused by landslides downtown continues to rise. Therefore, Aggressive efforts to break the traditional approach is needed to mitigate the landslides. Developed countries are actively adopting disaster mitigation policies and plans with land use policies and regulations. Typically, US natural disaster policy was converted into a long-term policy direction in the short-term approach. The disaster mitigation act (Disaster Mitigation Act of 2000, Public Law 106-390) was implemented by amending the Robert Stanford Disaster Assistance Act. The Europe is to establish a risk-based due to landslides in the 7th EU joint technology development program. The quantitative risk assessment and management plan for landslides was developed in social scale (local, regional and European). Thus consider the flow of international disaster management, emphasizing the relief phase, this study is to discuss the deployment direction of the integrated management system. The DB construction and predictive models for landslides disaster mitigation has progressed by the basis of historical trends. The foundation to present reasonable standard for landslides disaster risk mitigation and unstructured management will be provide. The systems are built in the long run we expect to increase significantly the level of decision-making in areas vulnerable to landslides spatial planning stages of the urban planning of the city municipality.
Development and Application of Precise Debris-flow Risk Assessment Index in Urban Area
Choi, Jung-Ryel ; Kim, Geon-Woo ; Jee, Yongkeun ; Park, In-Chan ;
Journal of Korean Society of Hazard Mitigation, volume 15, issue 3, 2015, Pages 107~113
DOI : 10.9798/KOSHAM.2015.15.3.107
In recent years, social demands for debris-flow disaster prevention measures are increasing because the more landslides make, the more loss of lives and property damages in urban area. However, in domestic, there are no precise indexes for the assessment of debris flow risk in urban area. For this reason, precise debris flow risk assessment indexes should be identified as a basic research. In this study, index of precise debris-flow risk assessment considering Korean situations was derived through the analysis of inventory system using HAZAUS-MH of FEMA. Twenty-one indexes have been selected and categorized as three groups such as population, buildings and infrastructures. Assessment indexes were validated by AHP expert survey as 73.5% for population, 14.8% for infrastructure and 11.7% for Buildings. The indexes were applied to assess debris flow risk in Seocho-gu, debris-flow damaged area as a case study. As the result of comparison between the results of Uran Vulnerability Assessment considering Climate change in 2011 and the results of this study, the precise debris flow risk assessment of building units could be conducted.
Analysis of Shelters Acceptable Range According to Evacuation Speed During Flood Disaster by Severe Rain Storm
Kwon, jinsuk ; Yoon, Donghyeon ; Koh, Junehwan ;
Journal of Korean Society of Hazard Mitigation, volume 15, issue 3, 2015, Pages 115~123
DOI : 10.9798/KOSHAM.2015.15.3.115
Due to abnormal climate, the flood disaster is occurred globally as well as domestically. The flood disaster measures have been researched continuously. In spite of the Prevention measures, the weather changes are difficult to predict accurately. So then, the evacuation places are essentially needed. The suitability of acceptable range of the current shelters is researched. This research is also analyzed whether both the ordinary people and elderly are considered when shelters are installed. Network analysis is conducted based on the evacuation speed of each subject. Vulnerable area is extracted as well. As a result, selection and management of the additional shelters are needed because the number and capacity of shelters is lacked in residential area.
Development of the Integrated Management System Prototype of Sediment Disaster Prevention Facilities Considering the Life-Cycle
Lee, Chanhee ; Lee, Heesup ; Sim, Oubae ; Kim, Wonhyun ; Yang, Dongmin ;
Journal of Korean Society of Hazard Mitigation, volume 15, issue 3, 2015, Pages 125~130
DOI : 10.9798/KOSHAM.2015.15.3.125
Recently, the importance of sediment disaster prevention facilities has increased because of climate change. However, they have some problems on the aspect of integrated management. The purpose of this study is to develop an integrated management system prototype of sediment disaster prevention facilities considering the life-cycle. This system prototype provides functions such as status, statistics, history management, notification of the facilities. It also assists the efficient management and long-term use of the facilities.
Development of Operation·Management System of Comprehensive Plan for Storm and Flood Damage Reduction
Joo, Jaeseung ; Jung, Dojoon ; Kim, Yuntae ;
Journal of Korean Society of Hazard Mitigation, volume 15, issue 3, 2015, Pages 131~139
DOI : 10.9798/KOSHAM.2015.15.3.131
Korean government has been executing the countermeasures and the projects on districts with high risks of natural disasters. These countermeasures are carried out through the establishment of Comprehensive Plan for Storm and Flood Damage Reduction (CPS-FDR), which is highly prioritized countermeasures of the disaster mitigation system in the Republic of Korea. However, it would be difficult to access and share the disaster-related information for making the report by local government, central government, and related agencies. In addition, damage and loss of the reports are often occurring by frequent change of the person in charge. Based on these problems of managing the report, this study presents an integrated-operating system which includes fundamental investigation, data of interesting area such as possible natural hazards of flood, landslide, and strong wind. Therefore, this study analyze configuration list of report and build up DB for development of system. Also, it suggests plan of advancement about operation-management System
Prediction of the Debris Flow-Prone Area in the Hilly District within Urban
Kim, Kyoung-Nam ; Jang, Su-Jin ; Lee, Kwang-Youn ; Seo, Gi-Beom ; Kim, Beom Soo ; Chun, Kun-Woo ;
Journal of Korean Society of Hazard Mitigation, volume 15, issue 3, 2015, Pages 141~146
DOI : 10.9798/KOSHAM.2015.15.3.141
As casualties are increased due to a landslide recently, it is emphasized that the division of a dangerous area from sediment disaster, specially in an urban area, is getting important. The aim of this study is to redefine how to delineate debris flow-prone area based on the hydrological micro-topography analysis techniques and to enhance the cognitive of residents on that risk in an urban mountainous area. As the results, movable sediment (
) is excessively larger than the erosional sediment (
), the range of runout distance is in order of using spread angle(
), set lowest part of the debris flow-prone area(
), using stream length(
), empirical formula(
). But the maximum distance is in
. Therefore, the value of (
) are proper in urban area, it was projected to be more proper that the value of (
) and (
) applicate in bigger watershed and lower development part. The method of hydrological micro-topography analysis is likely to contribute to strengthening the activity of social disaster prevention by enabling the self-diagnostic determination of inhabitants on dwelling areas.
Selecting the Criterion Factors for Keeping/Removing the Erosion Control District using Quantification Analysis II
Seo, Junpyo ; Youn, Hojoong ; Lee, Changwoo ; Gim, Sijun ;
Journal of Korean Society of Hazard Mitigation, volume 15, issue 3, 2015, Pages 147~154
DOI : 10.9798/KOSHAM.2015.15.3.147
An erosion control district should be designated to perform erosion control works. After such designation, an owner of the concerned land needs to obtain a permission to perform any development activities. To relieve the concerned area from such erosion control district, it should be judged that the concerned area has achieved an intended purpose of the designation after 10 years of such designation. This study was carried out to develop a reasonable basis to determine whether or not such designation should be maintained or terminated. Case study and quantification analysis were carried out to identify factors that influence such designation maintenance and termination and develop a judgement table. The factors identified in this study included the status of erosion control structures, coverage of grass, occurrence of soil erosion (Y/N), the status of downstream, growth status of planted trees and stability of other greening facilities. The judgement table was developed by giving weight to the factors based on the quantification analysis. It showed a high accuracy rate of 96.8% and correlation ratio of 0.61. This will serve as a basis to judge proper the designation duration of erosion control district.
An Evaluation on Fire Resistance Performances of CFT Columns According to Conditions Exposed to Fire
Kang, Hyun ; Lee, Deuck Hang ; Lee, Jung-Min ; Cho, Bum-Yean ; Kim, Kang Su ;
Journal of Korean Society of Hazard Mitigation, volume 15, issue 3, 2015, Pages 155~160
DOI : 10.9798/KOSHAM.2015.15.3.155
In this study, nonlinear finite element analyses were carried out on the squared concrete filled tube(CFT) columns according to the number of faces exposed to fire. The analysis results were compared to the test results obtained from literature, by which the accuracy of the nonlinear finite element analysis approach has been verified, and then, the parametric study has been conducted. As the number of faces exposed to fire increased, the fire performance of the squared CFT columns subjected to axial force only was degraded. It is, however, considered that their performance could be different when subjected to eccentric axial force, which would require further study in this regard.
Standardizing Acceleration Test Methods for Assessing the Durability of the Sprayed Fire Resistive Materials(II)
Kim, Dae-hoi ; Choi, Dong-ho ; Lee, Gun-chul ; Lee, Sae-hyun ;
Journal of Korean Society of Hazard Mitigation, volume 15, issue 3, 2015, Pages 161~167
DOI : 10.9798/KOSHAM.2015.15.3.161
The buildings constructed with steel structure is coated with certified Sprayed Fire Resistive Material(SFRM) to resist from fire. All the building materials lose their initial performances as time passes, so they need durability. In a previous Paper(Journal of The Korean Society of Hazard Mitigation in April 2014 to be posted) covered standardization of the methods for assessing the durability of SFRM. In Korea, more than 90 percent of SFRM are used indoors. So their fire performance were tested under indoor conditions before and after accelerate wet/dry cycling and temperature cycling to standardize the methods for assessing their durability. This paper is a follow-up study of the previous paper, that will be suggested the final draft based on validation tests and review the details for creating the Korea Industrial Standard.
Development of the Integrated Fire Suppression System in Intelligent Buildings
Jang, Joohwan ; Kim, Dongbum ; Shin, Byungjun ; Yoon, Sangchun ;
Journal of Korean Society of Hazard Mitigation, volume 15, issue 3, 2015, Pages 169~175
DOI : 10.9798/KOSHAM.2015.15.3.169
High-Rise and Large Office Building has potential elements of fire occurrence, it expects casualties and property damage in case of fire. For this reason, buildings build fire prevention system which included in the BAS(Building Automation System). But it operates separately and remains simple monitoring and control. Therefore, this research introduces the integrated platform for fire suppression which is developed with reviews of BAS and fire prevention systems in Intelligent Building. As a result, the proposed integrated platform for fire suppression consists of the fire detection algorithm using temperature data, the occupancy detecting algorithm using RFID, CCTV and PIR(Pyroelectric Infrared Radial) sensor, the fire suppression algorithm using HVAC system, and connections with Building Management System in BAS for fire situation.
A Study on Preventing Fire Spread of a Central Core-Opening Type Intelligent Buildings
Min, Se-Hong ; Bae, Yeon-Jun ; Lee, Jae-Moon ;
Journal of Korean Society of Hazard Mitigation, volume 15, issue 3, 2015, Pages 177~186
DOI : 10.9798/KOSHAM.2015.15.3.177
This study researched on the smoke control system which is applicable for delay and prevention on fire spreading in the most common case of central core open intelligent building. Fire simulation program (FDS) was used to analyze the effect on the applicability of selected fire scenarios on each case. As a result, I confirmed that fire shutters blocked fire spreading by limiting fire zone, but the effect of blocking fire spreading of smoke control window installed on one surface was reduced after time has passed. The study found that the area ratio and the height of windows and installation on multiple surfaces shall be considered in order to improve the smoke exhaust effect of smoke control window. Air flow of ventilation shall be calculated with the consideration of fire load and the HRR of internal combustibles and the smoke outlet are determined to be effective with securing a sufficient size in square shape. Especially the result of this study can be maximized by mixed complex operations of smoke control system which is proposed through this study rather than the individual applications.
A Study on the Development of Fire-resistance Wall Using a Cooling System in the Tunnel Safe Station
Chae, Seung-Un ; Shin, Hyun Joon ; Kwon, Ki Seok ;
Journal of Korean Society of Hazard Mitigation, volume 15, issue 3, 2015, Pages 187~191
DOI : 10.9798/KOSHAM.2015.15.3.187
The fire load of a tunnel fire event may have an huge heat release rate of over 100 MW. The tunnel lining may be damaged by the fire because the distance between the tunnel lining and fire is close. A lot of different damage that may occur to a tunnel lining structure during fire. Therefore, this study is desired to improve the fire-resistance of tunnel lining applying a water spray cooling system in order to protect it. The real scale fire test were performed. Experimental results, the ceiling of the tested specimen with an installed cooling system was observed no damage such as breakage or crack. And, after activated system the maximum temperature of the specimen was not reach
The ceiling of the tested specimen without an installed cooling system was observed that the temperature was raised rapidly. After approximately 216 secends the flame was spread and the ceiling was damaged.
Experimental Study on Thermal Damage of the Concrete Tunnel Lining Depending on the Fire Scenario and Fiber Addition
Kwon, Ki-seok ; Cho, Bum-yeon ; Chae, Seung-un ; Shin, Hyun-jun ; Park, Kyung-hoon ;
Journal of Korean Society of Hazard Mitigation, volume 15, issue 3, 2015, Pages 193~200
DOI : 10.9798/KOSHAM.2015.15.3.193
Many tunnels are under construction and have been completed due to the topographical characteristic in Korea. Also, further construction will be carried out. Meanwhile, it has been shown that for the fire trend over last 10 years, approximately 13% of overall fire accidents was caused by cars so that the tunnel has the potential risk factor at all times. Therefore, in order to reduce the fire damage of tunnel structures, various studies are under execution in the world but even regulations relating to the evaluation of the fire resistance performance is rarely settled on the tunnel lining in Korea. Therefore, in the study, the explosive spalling and thermal damage will be figured out by the fire resistance test of the concrete tunnel lining so that the results will be utilized as the basic data on the fire resistance design of the tunnel structure. As a result of that, it has been shown that for each case of the test adding the fiber and also without the fiber, the fire damage scope has been reduced as much as approximate 10~30 mm for the concrete and 20~40 mm for the reinforcement.
Analysis of Oil Well Cement Composition after Penetration Experiment with CO
Kim, Young Jin ; Yun, Tae Sup ; Youm, Kwang Soo ; Kim, Kwang Yeom ; Kim, Jung Joong ;
Journal of Korean Society of Hazard Mitigation, volume 15, issue 3, 2015, Pages 201~206
DOI : 10.9798/KOSHAM.2015.15.3.201
The integrity of oil well cement (OWC), cured under high temperature and pressure, may degrade upon the exposure to the
-saturated brine. In this study, a test setup was devised to examine the composition changes of hardened OWC due to the migration of
-saturated brine under high temperature and pressure. The Class G OWC cured at ambient conditions was used for the test set-up. The estimated pH of the brine saturated with
for 24 hours under 10 MPa and
was 3.14. The 3D micro computed tomography enables the evaluation of the spatial configuration of internal structures for carbonated produced by
in the hydrated OWC, corroborated by X-ray diffraction analyses that reveal the increment of
Nuclear Magnetic Resonance results showed the carbonation of calcium silicate hydrates (C-S-H) in the hydrated OWC.
Behavior of The FHT on Earthwork Section Considering Thermal Stress
Hong, Jun Ho ; Lee, Il Wha ; Chung, Wonseok ;
Journal of Korean Society of Hazard Mitigation, volume 15, issue 3, 2015, Pages 207~213
DOI : 10.9798/KOSHAM.2015.15.3.207
The fast hardening track(FHT) is developed to reduce maintenance cost and to increase strength of ballasted track. The ballasted track is reinforced by pouring mortar in the ballast. The allowable tensile stress of the FHT must be considered because the concrete slab of the FHT is plain concrete slab. The allowable tensile stress of the plain concrete slab is the fatigue strength because the concrete slab is loaded by a repetitive load of the train load and the temperature variation. At present, the research of thermal stress considering the structural specificity of the FHT is needed to design of the FHT. In this study, the trend between thermal stress and friction force is analyzed using finite element analysis, and the model to calculate of the allowable tensile stress of the FHT concrete slab is offered.
Evaluation of Debris Properties Using Numerical Analysis for USGS Debris Flume Tests
Shin, Hosung ;
Journal of Korean Society of Hazard Mitigation, volume 15, issue 3, 2015, Pages 215~221
DOI : 10.9798/KOSHAM.2015.15.3.215
Despite of recent active research on movement mechanism of debris flow, development of constitutive model and its necessary properties to determine flow characteristics is under slow progress. Rheologic-mechanical properties of debris material containing coarse sediment is so difficult to determine in laboratory tests that inverse analysis and parameter study for field and model measurements are necessary to evaluate the physical properties to simulate flow characteristics accurately. Parametric numerical study is conducted on USDS debris flume experiments from 1994 to 2004 (SGM case with high clay content, SG case with very low clay content). Numerical program simulates a single-phase flow based on the total stress analysis, and uses rheologic-mechanical constitutive model. Physical properties for the debris flow is determined to minimize the error between experimental and numerical results for arrival time and residual thickness of the debris flow (SGM case:
; SG case:
). Suggested constitutive model and its determined properties shows significant improvement in numerical prediction compared to a previous numerical study. However, different initial configuration of debris and modeling difficulty for debris discharge device cause slight discrepancy between numerical and experimental results.
Effect of Arrangement of Slit-type Barriers on Debris Flow Behavior: Laboratory-scaled Experiment
Choi, Shin-Kyu ; Lee, Jung-Min ; Jeong, HanBeom ; Kim, JiHeon ; Kwon, Tae-Hyuk ;
Journal of Korean Society of Hazard Mitigation, volume 15, issue 3, 2015, Pages 223~228
DOI : 10.9798/KOSHAM.2015.15.3.223
Debris flows caused by heavy rainfall occur along long watersheds and travel at extremely rapid velocity. This phenomenon involves fast moving fluids induced by gravity and causes economic and societal damages when debris flows overflow to urban area. For this reason, barriers against debris flows have been widely employed. In particular, slit-type barriers are popularly used because of the minimum disturbance to surrounding environments. However, the performance of such slit-type barriers is not fully understood. This paper explores roles of spacing and angle of slit-type barriers on velocity reduction and trap ratio of the debris flows. The scaled physical modeling experiments were performed to examine the reduction of debris velocity and trap ratio and to assess the performance of debris flow barriers. The results indicate that the performance of barriers is heavily affected by spacing between slit-type barriers and angle of barriers from flow direction.
A Study on the Criteria for Civil Evacuation Considering Rainfall and Geological Characteristics in Steep Slope Areas
Kim, Youl ; Ryu, Ji-Hyeob ; Seo, Sang-Hoon ;
Journal of Korean Society of Hazard Mitigation, volume 15, issue 3, 2015, Pages 229~236
DOI : 10.9798/KOSHAM.2015.15.3.229
For mitigating the damages of the steep
collapse, their collapse time should be expected in advance and then used to effectively evacuate the residents. For evacuation, evacuation management criteria has to be made yet by considering both the regional rainfall characteristics and the regional characteristics. As of now, evacuation management criteria have nationally included the same rainfall. With above in mind, this article comes to propose evacuation management criteria for the residents, which are protected under the authorities of local governments, by analyzing the five year rainfall and the soil characteristics. In particular, we are to set up the regional rainfall criteria by using not only about 700 cases of slope disaster but also related rainfall data. We continues to establish up the evacuation management criteria for the residents by utilizing the geological space in each administrative unit as well as the geological rainfall.
A Study on the Construction of the Routine Investigation & Inspection Table in the Hazardous Areas of the Urban Sediment Disasters
Sung, Hyun-Jong ; Ryu, Ji-Hyeob ; Kim, Youl ;
Journal of Korean Society of Hazard Mitigation, volume 15, issue 3, 2015, Pages 237~247
DOI : 10.9798/KOSHAM.2015.15.3.237
In this study were the routine investigation and inspection items selected that predict the risks of the sediment disaster through visual research of the researcher in the field by analyzing the sediment disaster practices and existing national and international investigation & inspection table and the final routine investigation & inspection table in the hazardous areas of the urban sediment disasters was constructed by drawing the investigation and inspection items to ensure the objectivity through the suvey targeted experts. The field survey was carried out on the test bed area and the results of the field survey using the constructed routine investigation & inspection table and existing disaster hazards estimation table were similar to confirm the applicability of the constructed routine investigation & inspection table. The routine investigation & inspection table constructed through this study will be verified and supplemented by applying to a variety of on-site in the next year research.
Application of Soil Surface Infrared Images for Geotechnical Non-destructive Testing Method
Kim, Hak-Seung ; Cha, Wonjun ; Cho, Namjun ; Kim, Hyun-Ki ;
Journal of Korean Society of Hazard Mitigation, volume 15, issue 3, 2015, Pages 249~254
DOI : 10.9798/KOSHAM.2015.15.3.249
Thermal diffusion process in soils reflects the engineering characteristics of soil components and internal structures. Based on the experimental and numerical observations on dry sand-rock deposits, different soil stratifications or structures can promote the different surface temperature changes by heating the surfaces even with the same heat source. This study suggests a method using the surface temperature changes to estimate the internal structure of the underground. Infrared images taken on the soil surface and thermocouples are used to measure the surface temperature changes with time. The results show that the surface temperature changes can be used as an index property to estimate the thickness of dry soil layer on the bedrock up to about 10cm.
A Study on the Effect for Restraining Lateral Displacement of Inclined Earth Retaining Wall through the Field Experiment
Seo, Minsu ; Im, Jongchul ; Kim, Jinsik ; Baek, Seungmin ; Kim, Junyoung ; Kim, Changyoung ;
Journal of Korean Society of Hazard Mitigation, volume 15, issue 3, 2015, Pages 255~264
DOI : 10.9798/KOSHAM.2015.15.3.255
An Inclined Earth Retaining structure method (IER method) using back supports has been developed to improve existing earth retaining structures (Seo et al., 2012). The earth retaining method uses the integrated system of an earth retaining pile (front support) and a stabilizing pile (back support). The back supports connected to front supports reduce the earth pressure acting on the front wall and front supports by distributing it to back supports in order to increase the structural stability. In this study, a field experimental testing was performed in order to analyze the effect of the back support reducing earth pressure acting on the earth retaining wall installed adjacent to an embankment. Using back supports resulted in the 22% reduction of restraining the lateral displacement of front supports. And result of analyzing by numerical analysis, if you install the same number of H-pile per the same length, was confirmed to have dual support reduced lateral displacement as compared to the single support.
Seismic Bearing Capacity of Shallow Foundation Supporting Single-Degree-of-Freedom Structures
Lee, Jin-sun ; Kim, Dong-Soo ; Ha, Jeong-Gon ;
Journal of Korean Society of Hazard Mitigation, volume 15, issue 3, 2015, Pages 265~273
DOI : 10.9798/KOSHAM.2015.15.3.265
The seismic bearing capacity of a shallow foundation supporting a single degree-of-freedom (SDOF) structure is examined through dynamic centrifuge tests conducted with dry silica sand layers and through the results of three-dimensional numerical analyses in time domain with explicit time integration. The numerical analysis model were constructed in prototype scale corresponding that of centrifuge test. The numerical analysis results correspond with the dynamic centrifuge test measurements. Thus, time histories of the bearing pressure beneath the shallow foundation is estimated from the numerical analysis. To examine the seismic behavior of a shallow foundation supporting a SDOF structure, two different seismic bearing capacity criteria were compared.
Future Trend Analysis of Hydrologic Time Series in Chungju Dam Basin Using Quantile Regression
Jun, Hwandon ; Kim, Soojun ;
Journal of Korean Society of Hazard Mitigation, volume 15, issue 3, 2015, Pages 275~283
DOI : 10.9798/KOSHAM.2015.15.3.275
The purpose of this study is to analyze future trend of hydrologic time series. We tried to analyze and compare the time series like precipitation, runoff, and storage volume series in Chungju Dam basin. Future daily weather series under climate change scenarios were collected, runoff and storage volume series were simulated using the SWAT as a rainfall-runoff model and the K-WEAP as a water balance model, Finally the selected hydrologic time series were monthly precipitation, runoff, and storage volume series. Eleven quantile regression lines corresponding to the quantiles (5%, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 95%) were estimated. This study assessed trend in the series at 5% significance level. Most series were shown a increasing trend at the high quantiles and a decreasing trend at the low quantiles. The variability of hydrologic series was expected to be more greater in the future.
Analysis of Debris Flow Propagation on Moving Bed
Jun, Byonghee ; Jun, Kyowon ; Kim, Byungsik ;
Journal of Korean Society of Hazard Mitigation, volume 15, issue 3, 2015, Pages 285~290
DOI : 10.9798/KOSHAM.2015.15.3.285
In this study, we investigated the propagation of the erosion/deposition in Takahashi model or Egashira model, which is well known as the debris flow simulation model. While as the equilibrium sediment concentration in Takahashi model depends on water surface slope as a stony type debris flow, immature type debris flow and the turbulent water flow, the equilibrium sediment concentration in Egashira model only depends on the equilibrium bed slope regardless of water surface slope. As the result of simulation, the Takahashi model shows the rapid erosion in high slope part and relatively small scale deposition. Because the Egashira model takes into consideration only the bed slope change, the deposition part is moved to upper stream region and shows the constant slope throughout the bed. This study revealed the 1D debris flow simulation model can support the poisoning of the debris flow control facility, and it was thought the progressed 2D simulation model will be valid for debris flow hazard map.
A Study on Landslide and Debris flow Area Risk Management Using Initiation and Runout Analysis Model
Lee, Chang Hee ; Oh, Kyoung Doo ; Oh, Kuk Ryul ;
Journal of Korean Society of Hazard Mitigation, volume 15, issue 3, 2015, Pages 291~296
DOI : 10.9798/KOSHAM.2015.15.3.291
The landslide due to heavy rains which generates debris flow, cause damages in the residential areas located in the valley. So far, landslide and debris flow risk studies have focused on the technology to find potentiality of a landslide in a region given a certain position. These techniques help to find a possible collapse position of a mountain, however the availability has been limited because it does not locate the debris flow risk zone for a given residential area around the mountain. This study aims to suggest a method to evaluate a broad area of landslide and debris flow risk for the mountain adjacent to a residential area by using the initiation and runout analysis model by linking the landslide risk analysis with the debris flow risk analysis. The method presented in this study will be useful tool to find identify the landslide and debris flow risk zone for broad area. This method is also expected to contribute in establishing a plan for damage and loss reduction.
Influence of the Spatial Distribution of a Raingage Network on the Estimation of Areal Average Rainfall : Focusing on Thiessen's Weighting Method
Lee, JiHo ; Jun, HwanDon ;
Journal of Korean Society of Hazard Mitigation, volume 15, issue 3, 2015, Pages 297~306
DOI : 10.9798/KOSHAM.2015.15.3.297
This study has evaluated how affect it is the spatial distribution characteristics of rainfall network for estimation of areal average rainfall. In addition, we reviewed whether it has any problem on Thiessen's weighting method which is used commonly in domestic when the spatial distribution of raingauge network is distorted. For that, the raingauge network is rearranged using the nearest neighbor index and the estimation error is estimated to rearranged raingauge network. Area average rainfall was estimated by arithmetic mean method, the Thiessen's weighting method and estimation theory for rainfall events. As a result, it found that the estimation error of area average rainfall is large on the distorted spatial distribution of raingauge network. Specially, it analyzed that Thiessen's weighting method occurred more larger estimation error of areal average rainfall than the arithmetic mean method on the distorted spatial distribution of raingauge network. Accuracy of the areal average rainfall is related with the density of the raingauge network besides the spatial distribution and it will be difficult to estimate the high accuracy of areal average rainfall even though the density of raingauge network on the distorted spatial distribution of raingauge network.
A Study of the Reasonable Operation Management on the Flood Pumping Station considering River Water Level
Song, Yang Ho ; Jo, Deok Jun ; Park, Moo Jong ; Lee, Jung Ho ;
Journal of Korean Society of Hazard Mitigation, volume 15, issue 3, 2015, Pages 307~318
DOI : 10.9798/KOSHAM.2015.15.3.307
In this study, the predicted rainfall estimation procedures were established based on the currently observable water level to reach a drainage gate for a short period time considering upper- flood pumping station section and down- stream point-based water level. The analysis was performed to prediction the reasonable operating point of the flood pumping station according to the down- stream point-based using water level change, targeting the Daerim3 flood pumping station located in Dorim stream basin, Yeongdeungpo-Gu, Seoul. During the course of research, analysis of the point-based water level relationship calculated the predicted rainfall amount for a reasonable operating point about flood pumping station. The result of a study, suggested a scenario-based analysis techniques and took into the feasibility of criteria gor the pump operating point and review of the predicted rainfall though a comparison of real-time water level observation and past record of pump operation.
Characteristics of Discharge Capacity due to the Variation of Downstream Water Level of the Multifunctional Movable Weir
Lee, Sang Hwa ; Noh, Seop ; Jang, Eun Cheul ;
Journal of Korean Society of Hazard Mitigation, volume 15, issue 3, 2015, Pages 319~327
DOI : 10.9798/KOSHAM.2015.15.3.319
A physical hydraulic model test was conducted to investigate the discharge capacity and flow characteristics for various downstream water levels of a multifunctional movable weir. The model, which can simulate the GangCheon Weir in the Han River, was provided on the scales of 1/60 and 1/20. With a given design flood discharge, the downstream design flood level was controlled at 0.5 m intervals (range -1.0 m to +1.0 m). In addition, the discharge capacities at various gate opening ratio were experimented on the scale of 1/20. As the test result, the discharge rating curves of the weir was proposed. Likewise, the experimental results can be utilized as the fundamental information for operating the gates and managing the weir.
Evaluation of Extended Inverse Distance Weighting Method for Constructing a Flow Duration Curve at Ungauged Basin
Yu, Jisoo ; Waseem, Muhammad ; Shin, Ji Yae ; Kim, Tae-Woong ;
Journal of Korean Society of Hazard Mitigation, volume 15, issue 3, 2015, Pages 329~337
DOI : 10.9798/KOSHAM.2015.15.3.329
This study evaluated the availability of a geographical and physiographical space-based extended inverse distance weighting (EIDW) method for constructing a flow duration curve (FDC) at ungauged basin. The method relies on two issues; (1) selecting an appropriate model for the approximation of FDCs at homogeneous gauging sites and (2) presenting significant interpolations to predict the stream-flow quantiles at ungauged site. This study investigated the performance of three parsimonious parametric models such as the linear, exponential and logarithmic model. This study then introduced the extended inverse distance weighting to develop a reliable ensemble averaging (REA) model through adapting three parametric models. The extended inverse distance weighting enables us to obtain optimal interpolation and high prediction efficiency after considering various range of distance decay parameter. Based on the cross validation using the root mean square error (RMSE) and Nash-Sutcliffe efficiency (NSE), the overall results revealed that the model with extended inverse distance weighting can provide more accurate, consistent and unbiased estimates of hydrologic quantiles compared to the traditional IDW.
Damage Assessment of Bridges Caused by Tsunami
Kim, Jin-Young ; Yoon, Joo-Seong ; Lee, Phill-Seung ; Kim, Young-Su ;
Journal of Korean Society of Hazard Mitigation, volume 15, issue 3, 2015, Pages 339~346
DOI : 10.9798/KOSHAM.2015.15.3.339
Recently, there has been an increasing concern on Tsunami along the east coast of Korea, that would be initiated from undersea earthquakes at the west coast of Japan. However, the possible property loss caused by Tsunami has not been studied well and the counter-plans to reduce the possible property loss have not been established yet. Especially, there does not exist any counter-plan against damage of civil engineering structures that could induce high property loss. In this study, we analyze the damage patterns of bridge structures, which is one of the typical civil engineering structures. First, we investigate damage cases of the East Japan Tsunami in year 2011. The typical destruction mechanisms of bridges are summarized. Then, bridges in a target area chosen along the east coast of Korea are classified. Based on their basic characteristics, estimated damage patterns and criterions of damage levels are established. Finally, the resistance of several standard bridges against Tsunami are calculated depending on inundation depths and we develop a damage assessment table for bridges against Tsunami.
Drought Severity - Duration - Frequency Analysis based on KMA 1-km Resolution RCP Scenario
Park, Myungwoo ; Sim, Hyun-Jun ; Park, Yoonkyung ; Kim, Sangdan ;
Journal of Korean Society of Hazard Mitigation, volume 15, issue 3, 2015, Pages 347~355
DOI : 10.9798/KOSHAM.2015.15.3.347
In this study, the impact of climate change on extreme drought events is investigated by comparing drought severity-duration-frequency curves under present and future climate conditions. In our climate-change impact experiments, the future climate is based on South Korea-detailed 1-km resolution data of Korea Meteorological Administration(KMA) future climate information. RCP 2.6, 4.5, 6.0 and 8.5 are applied as future climate scenarios. As a result, future drought events under RCP 2.6 and 4.5 are generally worse than the present, future drought events from RCP 6.0 are weaker, and future drought under RCP 8.5 is similar to the present drought as a whole.
Evaluation of Infiltration/Inflow on Separate Sewer System in Residential Complex
Choi, JongSoo ; Lee, YunSang ; Lee, YuJin ; Lee, JungMin ;
Journal of Korean Society of Hazard Mitigation, volume 15, issue 3, 2015, Pages 357~362
DOI : 10.9798/KOSHAM.2015.15.3.357
Using field studies on sewage flows and Infiltration/Inflow(I/I) analysis in separate sewer systems, the appropriate I/I values were computed, and an alternate method of calculation for I/I was presented. Sewage flows followed a typical diurnal pattern with highs in the morning and evening and lows during the night. The BOD concentration of sewage ranged from 200 to 400mg/L. Diurnal variations in BOD concentration fell slightly during the night, when there were low sewage flows. This is likely the result of dilution due to the inflow of groundwater, but it was difficult to quantify the effect. The infiltration varied considerably in the data, from -14.8% to 14.0% of the daily maximum sewage flow. This is due to the limitations of the method of calculations rather than errors in measurement. In short, the method of calculation for night-time domestic flow only takes into account the population of a particular region. Therefore, if the characteristics of night-time activities of residents are different, the method is unable to reflect it. As such, the method of calculation should be updated with continued research. Analysis of the inflow showed that the specific inflow rate was 0.7 to
, lower than the results of similar studies. The values were higher for regions where the pipe lengths were longer and had a larger number of house-inlets.