Go to the main menu
Skip to content
Go to bottom
REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
Journal of the Korean Society of Safety
Journal Basic Information
Journal DOI :
The Korean Society Safety
Editor in Chief :
Volume & Issues
Volume 13, Issue 4 - Dec 1998
Volume 13, Issue 3 - Sep 1998
Volume 13, Issue 2 - Jun 1998
Volume 13, Issue 1 - Mar 1998
Selecting the target year
Instrumented Drop Weight Impact Testing of Polymer Materials
Journal of the Korean Society of Safety , volume 13, issue 2, 1998, Pages 3~12
Polymer materials have been used offensively as construction materials for automobiles, ships, and airplanes in recent years, and their impact resistance has been obliged to be examined. In the present study, a dropped load and a specimen, equipped with high responsible strain gauges respectively, were dropped and then the changes of load and absorption energy with time were observed. It was found that the waveforms for dropped weight coincided with output signal wave for specimen during the destruction test. Based on this experimental result, three disc type of specimens with different compositions were prepared and examined. This instrumented impact test method showed that each specimen can be distinguished from each other better than conventional tests and is expected to contribute to assess test results of impact resistance for some materials under development.
A Study on the Vibration Characteristics for Safety Design of Vehicle Structure
Journal of the Korean Society of Safety , volume 13, issue 2, 1998, Pages 13~21
This is a study on the natural vibration characteristics of Vehicle frame. Nowadays, many trucks freight the over-load, do the car designers consider the over-load about 200% in the design. It's necessary to make the model of a vehicle and simulate it for the test of driving condition, durability and vibration behavior before the vehicle is manufactured. If it is possible to make a simulation using the static and dynamic analysis, this is very useful in accomplishing an optimal design of the vehicle. In this paper, we studied the vibration characteristics of a truck body frame. The automobile body frame model for experiment is made smaller than real size frame with the ratio of 1/10. The vibration characteristics of a frame is considered as one of main factors in analyzing and improving the problem for ride comfort, noise and vibration reduction. Therefore, we experimented two method to neglect the nonlinearity. First is bolting and second is welding at the joint section. We compared computer simulation results and experimental data.
Numerical Analysis of Heat Transfer of a Printed Circuit Boards for Safety Design of Electronic Equipment at Each Design Stage
Journal of the Korean Society of Safety , volume 13, issue 2, 1998, Pages 22~29
The natural convection cooling of simulated electronic chips located on a printed circuit board(PCB) has been studied by Computer Aided Engineering(CAE). In CAE, 3-dimensional finite element model of simulated electronic chip was made to accomplish heat transfer analysis at each design stage of a printed circuit boards for thermal optimization. The simulated electronic chips are installed protrudent from the plate about 3mm. The materials the plates are epoxy and aluminum. The results show that the chip with relatively high heat generation rates should not be close to each other. It is found, as well that cooling effect for the aluminum plate is superior to the epoxy plate and location of maximum temperature is significantly influenced by the structure variation of PCB. In developing PCB and electronic chips, it's recommended that CAE is very useful to estimate to the distribution of temperature.
A study on impact collapse characteristics of CFRP thin-walled laminates under high temperatures and hygrothermals
Journal of the Korean Society of Safety , volume 13, issue 2, 1998, Pages 30~38
In this study, in order to measure energy-absorbing characteristics in impact test of CFRP thin-walled laminates and interpret the cause of decreasing age when collapse test is carried out under the environments of high temperatures and hygrothermals, the moisture absorbing behavior according to the variety of orientation angle is observed and impact collapse characteristics of no moisture absorbing status is compared with that under the environments of high temperatures and hygrothermals. Especially, we try to obtain quantitative design data to develop CFRP thin-walled laminates with energy characteristics of optimum impact absorbing. The value of the maximum loading, mean loading, rate of energy absorption energy per unit volume and mass in CFRP thin-walled laminates on the high temperatures and hygrothermals is measured much lower than under no moisture absorbing. The maximum collapse loading in dynamic impact test is taken measurements lower than in static collapse test CFRP circular laminates in high temperatures and hygrothermals. But the absorbed energy per unit mass and volume is almost same each other and the biggest amount of energy is shown in CFRP circular laminates with orientation angle of
. Therefore, in the case of using CFRP circular laminates with axisymmetric mode, CFRP thin-walled structural members with orientation angle of
has generally best condition.
A Study on Feasibility of Oil Separation with Oil Absorbent for Spilt Oil Recovery
Journal of the Korean Society of Safety , volume 13, issue 2, 1998, Pages 39~44
An experimental study on oil absorbent was conducted to investigate the feasibility of utilizing absorbents in oil separation from water-oil mixture for spilt oil recovery. Experiments included investigations of absorptivity and filtering performance of a commercial oil absorbent for different diesel oil concentrations. The measured average absorptivity of the absorbent was above 92% for oil concentrations, 5, 10, 15vo1%, that shows good absorbing performance. Filtering the oil-water mixture, however, was too slow to be used for oil separation. An absorbent baffle system was suggested for oil separation which collects oil panicles by increasing contact between the absorbent and oil particles.
A Study on the Influence of its Constituents on the Creep Behavior of High Temperature Composite Materials
Journal of the Korean Society of Safety , volume 13, issue 2, 1998, Pages 45~53
A method to predict the creep behavior of fiber-reinforced ceramic composites at high temperatures was suggested based on finite element modeling using constituent creep equations of fiber and matrix and showed good agreement with the experimental results. The effects of matrix creep behavior, fiber volume fraction, and residual stresses on the composite creep behavior were also investigated. The results showed that the primary behavior of composites was greatly affected by that of matrix but post-primary behavior was governed by fiber creep characteristics. The increase of fiber volume fraction from 15 vol% to 30 vol% caused the 50% and 40% decrease of steady-state creep rates and total creep strains at
, 180MPa, respectively. Feasible compressive residual stresses in the matrix caused by different thermal expansion coefficients between the fiber and the matrix could significantly reduce total creep strains of the composite. The creep deformation mechanism in the fiber-reinforced ceramic composites could be explained by the stress transfer and redistribution in the fiber and matrix due to different creep characteristics of its constituents.
Analysis of Stresses on Buried Natural Gas Pipeline Subjected to Ground Subsidence
Journal of the Korean Society of Safety , volume 13, issue 2, 1998, Pages 54~64
This study was initiated to examine the stress and deformation characteristics of the pipelines which were subjected to various environmental conditions in order to confirm their integrity. As the part of them, this paper presents the analysis results for the effect of ground subsidence combined with main loads on buried natural gas pipelines. The ground subsidence which can occur for buried gas pipeline has been classified to the three cases. Finite element method was used to analyze the effect of ground subsidences on pipeline of 26 inch(0.660 m) and 30 inch(0.762 m) diameter used as high pressure (
) main pipelines of KOGAS. This paper shows the result of stress analysis for the pipelines subjected to those three case ground subsidence. Comparing these results with safety criterion of KOGAS(0.9
), maximum allowable settlement and loads have been calculated.
A Study on the Evaluation of Welding Fume Generated during Arc Welding
Journal of the Korean Society of Safety , volume 13, issue 2, 1998, Pages 65~75
The cases of welders illness by welding fume generated during arc welding are recently reported, which makes the legal regulation in the welding work place. Also, this situation makes the employers and welders be concerned about the welding fume seriously. At this point of time it is necessary that a standard testing method is developed as a fundamental tool for the evaluation of Fume Generation Rate(FGR) required for making progress in the development of low fume electrodes and welding process technology and also constructing the ventilation system in welding area. However, the current standard(KS D 0062) is only applicable to the manual covered electrode arc welding. In this study the evaluation procedure for the FGR is established by developing the fume collection chamber which can be applicable to semiautomatic and automatic arc welding as well as manual arc welding. This evaluation system and procedure can be used as a tool not only to develop the low fume welding electrode and welding process technology but also to construct the equipment controlling the welding workshop atmosphere.
Control of Hydrocracking Temperature in Ebulated Recycle Reactor
Journal of the Korean Society of Safety , volume 13, issue 2, 1998, Pages 76~87
This study was carried out to investigate the effect of on temperature control from actuating method, recycling ratio and the position (top, middle and bottom) of set and controlled temperature within the reactor in adiabatic ebullated recycling condition, when the disturbance was occurred. Estimation of the solution were performed numerically using the finite difference method. It was assumed that the reaction is in constant with heat of reaction and the physical properties(density, heat capacity and viscosity, etc) of the reactants are same condition within the reactor.
A Study on the Combustion Characteristics of the Automotive Interior Materials
Journal of the Korean Society of Safety , volume 13, issue 2, 1998, Pages 88~95
Five parts of the automotive interior materials were sampled to determine their combustion characteristics. Oxygen Indexer, Smoke chamber, Differential Scanning Calorimeter(DSC) were used as the analysis apparatus. All LOI values of samples appear less than 21. The combustion phenomena of the interior materials primarily depends on properties of each layer material. The amount of generated smoke are reached the maximum value within 30 - 90sec after ignition. The experimental results of combustion characteristics and DSC of H/Line also indicated that the layer of foam was melt first and it caused the propagation of flame through the sample. The combustion characteristics of multi-layer materials primarily depends on thermal characteristics of single layer material.
A Study on the Electrochemical Treatment of Wastewater Carmine-6B Dyes in a Batch Reactor
Journal of the Korean Society of Safety , volume 13, issue 2, 1998, Pages 96~103
The treatment of the wastewater of Carmine-6B Process was studied using an electrochemical batch reactor with Pt-electrodes. The concentration of azo dye was exponentially decreased unto 6-37% residuum during 50 hr operations. The fractional conversion was not influenced by the initial pH value, but it was increased with increasing the rotating speed and/or temperature of the electrolyte. It was observed by the differential method of rate analysis that the rate of the oxidation reaction at anode was exponentially increased with increasing the cell voltage. The pH of the wastewater was changed from acid or alkali to neutral. The COD of the solution was increased at the beginning of the treatment, but it was decreased soon.
Evaluation of Popping Performance of Safety Valves in City Gas Facilities
Journal of the Korean Society of Safety , volume 13, issue 2, 1998, Pages 104~108
In order to evaluate the performances of safety valves for low pressure, the popping pressure and flow rate of the natural gas have been investigated. The measured results of the popping pressure show that there is a big scattering depending on the manufacture year of a safety valve. And sample A showed the ideal popping pressure mode compared to other B and C samples. The popping flow rate of the safety valve is proportional to the seat size as the inlet pressure increases. These results may be used as a guideline for a design and diagnosis of the safety valve.
Study on separation process of tri-cresyl phosphate by reaction of
with mixed cresol
Journal of the Korean Society of Safety , volume 13, issue 2, 1998, Pages 109~115
Tri-cresyl phosphate(TCP) was synthesized by reaction of phosphorus chloride with mixed cresol(mixture of m-cresol, p-cresol, and others) in the presence of
. Some of unwanted products and unreactants colored TCP. In order to separate TCP from these, vaccume distillation was carried twice, but colorless TCP could not be producted. Separation of unwanted materials by 2% NaOH solution was introduced before first and second distillation and optimal separation conditions such as NaOH concentration, mixing volume ratio, mixing time, and rpm were investigated for new batch separation and production of colorless TCP Optimal conditions were 2% NaOH solution, 35% mixing volume ratio of 2% NaOH solution, 1.5 hours of mixing time, and 20 rpm.
A Study on the Explosion Limit and Explosion Characteristics of Flammable Vapor
Journal of the Korean Society of Safety , volume 13, issue 2, 1998, Pages 116~121
Various flammable vapors as energy source and raw material have been stored, transported in the industries, and accidental leakage of these vapors occurs occasionally. Without an appropriate protection system, flammable vapors can be ignited and serious damage results from them. To reduce the risk caused by explosion, we should know the explosion limit and explosion characteristics. In this study, the maximum explosion pressure, the maximum explosion pressure rise, the effect of temperature and mixing with other vapor were measured in a cylindrical vessel. Experimental results showed that maximum explosion pressure of flammable vapor was about 3.1~
and it was reached 3.4 times faster than that at explosion limit. The lower explosion limit was coincided well with Le Chateilier's equation, however, upper explosion limit was not.
Mechanical Properties and Economic Evaluation of Steel Fiber Reinforced Shotcrete
Journal of the Korean Society of Safety , volume 13, issue 2, 1998, Pages 122~129
A field experiment was performed to analyze the properties of SFRS(steel fiber reinforced shotcrete) against WMRS(wire mesh reinforced shotcrete) with some experimental parameters. The parameters were reinforcing methods(steel fiber and wire mesh), steel fiber contents(0.5%, 0.75%, and 1.0%), silica fume contents(0.0% and 10.0%), spraying thicknesses of layer(10㎝, 8㎝, and 6㎝), and spraying parts(side wall, shoulder, and crown). According to the analyzed results, the mechanical properties of SFRS such as compressive strength, flexural strength, and load-carrying capacity after cracks were improved. And the economic evaluation was also performed on the basis of the required thickness of the layer and other researcher's results for rebound ratios. From the results of this tests, it is found that the traditional WMRS may be substituted by the SFRS in the viewpoint of the economic evaluation as well as the mechanical properties. In additions, the silica fume, even if it is very expensive, can significantly improve the mechanical properties of the shotcrete regardless of mixing with or without the steel fiber.
Case Study on the Improvement of Cosmetic Product Safety
Journal of the Korean Society of Safety , volume 13, issue 2, 1998, Pages 130~135
One aspect of customer dissatisfaction, safety or more correctly, the lack of product safety has received particular attention in courts and in legislatures, especially in the developed countries. Therefore, many companies have always regarded safety elements as an essential part of product manufacturing. In this paper, the case study on the product safety of infant cosmetics manufactured by a small-medium enterprise is presented. We have focused our study on safety level and control system of product safety, also analyzed the product defects caused by mixing process and all departments. It is found that the product defects(Complaints, Enquiries) is considerably decreased. These results could be used to deal with a product recall which companies hope never happens to them.
A Study on rapid evaluation of reliability for acyclic non-linear graph
Journal of the Korean Society of Safety , volume 13, issue 2, 1998, Pages 136~144
FTA is the most commonly used method among quantitative safety assessment. In case that the observing system become larger, a lot of terms should be calculated to accomplish FTA through complicated process. Many methods have been tried to reduce time, one of tries is How to calculate the reliability using graph theory after changing W to graph. This paper suggests an algorithm that can calculate more rapidly reliability and outset of system expressed by non-linear graph as like as FTA or CCA.
The Characteristics of Occupational Injury in Small Manufacturing Factory
Journal of the Korean Society of Safety , volume 13, issue 2, 1998, Pages 145~150
The production activity by human is accompanied by various accidents which resulted in human and property loss. If information on these industrial accidents could be collected and analyzed for the purpose of preventing industrial accidents, we would be able to get rid of industrial accidents. The accidents which involved absence from work at least 4 days in small manufacturing factories were considered in this study. 84 accidents which occurred in 1995 were investigated. These accidents were analyzed in terms of employment sector, work period, cause of accident and form of accident. The accidents of small manufacturing factories are numerous and are often serious and worthy of greater attention than they have received. Successful strategies for accident prevention depend on effective analysis.
A Study on the Decision-Making Process of the Occupational Safety & Health Policy
Journal of the Korean Society of Safety , volume 13, issue 2, 1998, Pages 151~163
The government policy on the occupational safety and health is the fundamental factor for the effectiveness and efficiency of the accident prevention efforts. However this point of view is comparatively neglected and most of policy in occupational safety and health has not been successful enough in Korea. Thus, this study aims to reduce the accidents at work in Korea through the improvement of the decision-making process on the occupational safety and health policy in Korea. The recommendations are derived from the comparison between the policy decision-making organization and process of Korea and those of other major countries. Capitulated recommendations are: more involvement of professional individuals in the process of policy decision-making; intensive utilization of research institutes; and more openness of the process of policy decision-making to the stakeholders ie, the representatives of employees and employers.
Experimental Investigations of Sideward Burr Formation in 3-Dimensional Cutting
Gi-Heung Choi ;
Journal of the Korean Society of Safety , volume 13, issue 2, 1998, Pages 164~169
Burrs can be formed on the feed marks ridges as well as on the edges of the machined parts in machining operations. These burrs are undesirable in terms of the surface quality, the precise dimensioning of machined parts and the safety of operators. This paper experimentally investigates the sideward burr formation in 3-dimensional cutting. In particular, the experimental relationships between the size of sideward burr and the cutting parameters are established and suggestions are made for minimizing sideward burr formation.
A Methodology for Assessing Risk from Released Hydrocarbon
Keun-Won Lee ;
Journal of the Korean Society of Safety , volume 13, issue 2, 1998, Pages 170~180
This study presents a method for calculating the concentration of hydrocarbon releases in enclosed areas using empirical equations of evaporation rate. The approach of the method is to estimate the hydrocarbon exposure concentration in the air under conditions assumed. A methodology for assessing risk was suggested to individual risk assessment to exposed workers or others by probit expressions. The toxicity criteria and available human exposure data were examined and guidelines for risk assessment suggested for benzene-air and toluene-air systems. The value of probit constants with mole fractions of lethal concentrations in a mixture of hydrocarbons and a non-toxic substance was predicted. The probit values calculated with mole fractions can be used to estimate guidelines to prevent toxicity within enclosed working areas.