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
Theoretical Study on The Stability of the Cantilever Beam Subjected to a Follower Force
Journal of the Korean Society of Safety , volume 13, issue 1, 1998, Pages 3~12
On the stability of the cantilever beam subjected to a follower force at the free end, the influences of the translational spring and the moment of inertia of a tip mass at the free end have been studied by numerical methods. The centroid of a tip mass is offset from the free end of a Beam and is located along its extended axis to vary the value of moment of inertia of a tip mass. It is proved that as the constants of a spring supporting the free end are augmented, the critical flutter loads of the above system decrease, whereas they increase without a tip mass.
Evaluation on The Fracture Toughness of Chopped Strand Reinforced ALS Matrix Composites
Journal of the Korean Society of Safety , volume 13, issue 1, 1998, Pages 13~18
It is well known in the fracture mechanics community that the fracture toughness of brittle materials, such as ceramics, can be improved improves significantly when fibers are added into the material. This is because in presence of fibers the cracks cannot propagate as freely as it can in absence of them. Fibers bridge the gap between two adjacent surfaces of the crack and reduce the crack tip opening displacement, thus make it harder to propagate. Several investigators have experimentally studied how the length, diameter and volume fraction of fibers affect the fracture toughness of chopped strand reinforced matrix composite materials. In this paper, matrix used ALS, Arizona Lunar Simulant, types of fiber used carbon steels and stainless steels. To analyze quantitatively fiber reinforced ALS composites, experimental and analytical methods was progressed. Load-displacement curve is used to experimental method, and FEM analysis program using ABAQUS is used analytical method.
The Effect of the Injection Molding Conditions of Plastics on the Stress Relaxation
Journal of the Korean Society of Safety , volume 13, issue 1, 1998, Pages 19~25
In this study, proper injection molding condition has been studied through stress relaxation tests in order to experimentally investigate the effect of the condition on softening of mold product, using specimens produced under the different conditions according to the recommendation of resin manufactures. As a result, softening of the specimens was found to be strongly influenced by material melting temperature. The specimen with higher material melting temperature is found to have lower softening. However, softening of the specimen with lower mold temperature has an decrement, compared with other specimens. In particular, specimen with notch is influenced by mold temperature. The softening increase with higher injection speed and pressure. Finally in order to improve softening, material melting temperature, injection speed and injection pressure were found to be increased with low mold temperature.
A study of Heat Transfer by the Finite Element Method - Around Square Heat Source -
Journal of the Korean Society of Safety , volume 13, issue 1, 1998, Pages 26~33
This paper subdivided the interior solid into triangular shape of equal size to calculate the temperature distribution around the square heat source of it, and compared calculated values with measured ones. The result obtained are as follows. 1) It was found that we can calculate the temperature distribution around the square heat source of interior solid by the variational method of the finite element method as the calculated values were almost accord with the measured ones. 2) The temperature distributed were higher when the distances between heat source were farther and lower when those nearer. 3) Vertical surface temperature distribution is remarkably efficient by thermal conductivities.
Effect of Offset of Bearing on Radiation Sound and Vibration in the Gear System
Journal of the Korean Society of Safety , volume 13, issue 1, 1998, Pages 34~39
This paper describes a evaluation method of sound power radiated from the vibrating faces of a single stage gear box using sound radiation. The vibration caused from meshing gears is transmitted to the gear box faces through shafts and bearings. A Boundary Element Method (BEM) is developed to calculate the sound power radiated from the faces with their velocity response which is based on the Building Block Approach (BBA). Radiation efficiency as well as the sound intensity on the surface of the gear box is also calculated. Sound power of the gear box is larger in the case that bearings have offset to the wall of the gear box than that bearings are on the center of the gear box. The sound power increases with the augmentation of the offset.
A Study on the Masses Reduction for the Structural Safety Using Optimal Design Method
Journal of the Korean Society of Safety , volume 13, issue 1, 1998, Pages 40~46
This paper is presented that theoretical optimization design method in order to consider mass reduction for the structural safety In this paper, it described methods for reducing vibration in structural safety by the determination of the optimum sizes and locations of tunning masses through formal mathematical optimization techniques. The optimization procedure which employs the tunning masses and corresponding locations is developed. Design variables are systematically changed to achieve low values of shear without a large mass penalty. Three optimization methods ire developed and tested. The first is based on minimizing the modal shaping parameter which indirectly reduce the modal shear amplitudes corresponding to each harmonic of airload. The second method reduces these amplitudes directly and the third method reduces the shear as a function of time during a revolution of the blade. The first method works well for reducing the shear for one mode responding to a single harmonic of the airload but has been found in some bases to be ineffective for more than one mode.
A Study on Failure Prevention of Radiant Heater Tube
Journal of the Korean Society of Safety , volume 13, issue 1, 1998, Pages 47~53
Radiant heater tubes with an inside burner are designed to transfer the heat generated from the burner to the outside of the tube by radiation. Hence, tube metal must suffer high temperature of approximately 900-
. The radiant tube is usually manufactured by centrifugal casting with high Ni-Cr alloys. In this study, failure analysis results of the radiant tube are reported. Failure mechanism of the tube was investigated by visual observation of the foiled tube, metallographic study of the cracked region and chemical analysis of tube metal and oxide scales. It was argued that the main cause of the cracking is repeated oxidation of the tube metal located beneath the thick oxide scale. Oxidation was caused by abnormally high operating temperature which can be verified by aged microstructure and internal void formation.
Design of an Observer for Position and Speed Sensorless Vector Control of PMSM
Journal of the Korean Society of Safety , volume 13, issue 1, 1998, Pages 54~63
This paper proposes a theoretical analysis of a closed loop adaptive speed control system for control the inverter driven permanent magnet synchronous motor(PMSM). This control system utilizes a mechanically sensorless state observer for the generation of all controller feedback information. The observer processes measurements of stator frame voltage and current to produce estimates of rotor position and speed and rotor frame currents. It is shown that the identity observer, when properly formulated, has the same linearized error dynamics as the extended kalman filter(EKF). Consequently, it is shown that the gains within the identity observer can be designed in a manner identical to that of the EKF. In this way, the designability of the nonlinear observer is assured, as is the optimality of its performance for small errors. A sequence of simulation are performed and they demonstrate the successful performance.
Synthesis and Surface Activities of Perfluoro Hetero Type compounds
Journal of the Korean Society of Safety , volume 13, issue 1, 1998, Pages 64~69
Three kinds of N-fluoroacyl carboxy pyridinium chlorides were synthesized by the reaction of pyridine-carboxylic acid such as pyridine-2-carboxylic, pyridine-3-carboxylic and pyridine-4-carboxylic acid with long chain perfluoroacyl chloride. The surface chemical properties including surface tension, foaming power, foam stability, effectiveness of wettability and solubilizing effect were measured. These compounds showed good surface activities as emulsifying agent, solubilizing agent and fire-fighting agent.
A Numerical Study of Smoke Movement by Fire In Atrium Space
Journal of the Korean Society of Safety , volume 13, issue 1, 1998, Pages 70~76
The smoke filling process for the atrium space containing a fire source is simulated using two types of deterministic fire models : Zone model and Field model. The zone model used is the CFAST(version 1.6) model developed at the Building and Fire Research Laboratories, NIST in the USA. The field model is a self-developed fire field model based on Computational Fluid Dynamics(CFD) theories. This article is focused on finding out the smoke movement and temperature distribution in atrium space which is cubic in shape. A computational procedure for predicting velocity and temperature distribution in fire-induced flow is based on the solution, in finite volume method and non-staggered grid system, of 3-dimensional equations for the conservation of mass, momentum, energy, species and so forth. The fire model i. e. Zone model and Field model predicted similar results for the clear height and the smoke layer temperature.
Object-Oriented Modelling for Automated HAZOP Analysis
Journal of the Korean Society of Safety , volume 13, issue 1, 1998, Pages 77~84
Hazard and operability (HAZOP) analysis is one of the safety analysis method that is used in the chemical complex, because it can systematically identify causes and consequences of all the deviation that could occur. Since this method needs to hire specialized experts, it is costly and time-consuming. Therefore HAZOP Expert System has been developed to automate this analysis. This approach introduced object-oriented method and knowledge representation which is hierarchical tree of units to supply flexibility in the system, functional semantic network, propagation equation and rule-chaining method to set up the expert system for automating HAZOP analysis.
Preparation of Glass Thin Film onto Plastic Surface by Sol-Gel Process
Journal of the Korean Society of Safety , volume 13, issue 1, 1998, Pages 85~91
Sol-gel derived silica films were prepared by dip-coating onto polymethylmethacylate with Tetraethoxysilane(TEOS) as starting materials. Film properties such as viscosity and thickness were investigated as a function of dip speed, waterprecursor ratio, sol aging time. IR spectra of the gel films prepared from TEOS at various R are given. At small values of R the absorption peaks assignable to C-H vibration in
groups are observed around 3000 and 1500-1300
. These bands indicate that the -
groups are retained in the gel at small values of R because of incomplete hydrolysis of TEOS. Film behaviour was interpreted in terms of the dependence of hydrolysis and condensation rates on the interplay between sol pH and waterprecursor ratio. Film thickness was found to increase by approximately a factor of two as waterprecursor ratio increased from two to six. Film thickness also increased with sol prepolymerization time. Surface quality was correlated with processing conditions.
Removal of Alkali Odors using Impregnated ACFs
Journal of the Korean Society of Safety , volume 13, issue 1, 1998, Pages 92~97
Malodorous gases give discomfort and harm to laborers and residential neighborhoods and therefore, the removing odor materials emitted from plants and industrial facilities is important subject. The main ingredients of alkali odor are
. The adsorption characteristics of odors were studied using four different activated carbon fibers(ACF) and active carbon(AC). Alkali odor was removed by using ACF impregnated with
and treated with
and NaOH. The experimental result showed that ACF has a higher removal efficiency than AC. The adsorption capacity was increased with the impregnation and surface treatment, and
was the best impregnant for the removal of alkali odor.
A Study on Development of Risk Assessment System for Industry Facilities Using DataBase
Journal of the Korean Society of Safety , volume 13, issue 1, 1998, Pages 98~104
Recently, industrial accidents have occurred in various patterns due to the diversity of industries and the integration of facilities. Especially, the major accidents affect broad area and result in huge loss of lives and properties. Domestic researches on techniques for keeping away from such hazardous danger have been actively performed but their activities are limited in some institutes and universities. In advanced countries, integrated management systems like Seveso Directive of EU and OSHA(Occupational Safety and Health Act) of U.S.A. have been legislated along with the systematic research activities. In Korea, the integrated safety management systems called SMS(Safety Management System) and PSM(Process Safety Management) have been applied to major industries. These systems made chemical industries manage the process safety information by collecting and arranging safety data by themselves. In order to implement the system successfully, it is urgently required to prepare a tool for searching and accumulating process safety data systematically. In this study, a computerized prototype of Risk Assessment System which is essential to SMS and PSM was developed as a main system and data base as subsystem to handle safety information.
Statistical analyses on the damage consequences of occupational accidents in construction work
Journal of the Korean Society of Safety , volume 13, issue 1, 1998, Pages 104~111
Statistical analyses of occupational accidents associated with construction work were carried out to explore the basic statistical characteristics of their damage consequences. Emphasis was placed upon the probabilistic and statistical analyses to clarify, in particular, the relationship between frequency of labour accidents and their damage consequences. Damage consequences were classified into two categories such as the number of workdays lost due to accidents and the number of injured workers involved in one accident. Two types of accident data were collected for the analyses. From the analyses, it was found that the relation between damage due to accidents and their frequencies can be represented by a simple power function which indicates a log-log linear relation. By making use of this relationship, various probabilistic evaluations such as the estimation of the mean time periods between accidents, expected damage consequences, and expected damage ratio between different mean time period of accidents were conducted.
Development and An Application of A New Human Reliability Analysis using Dynamic Influences
Journal of the Korean Society of Safety , volume 13, issue 1, 1998, Pages 112~118
Human errors performed during the operations have a dominant portion of the accidents. But the systematic human error evaluation methodology universally accepted is not developed yet. One of the difficulties in performing human reliability analysis is to evaluate the performance shaping factors which represent the characteristics and the circumstances in the discriminate manner. For assessing a specific human action more exactly, it is necessary to consider all of the PSFs at the same time which make an effect on the human action. In this paper, dynamic influence diagrams are introduced to model simultaneously their effects on the specific human action. And the human actions and their subsequent PSFs are categorized and classified as the complementary works. A new human error evaluation methodology using influence diagrams is developed. This methodology involves the categorization of PSFs and the PSFs quantification. The applied analysis results for the example task are shown for representative purposes. It is
A Study on Safety Consciousness for Preventing Accident of The Shipbuilding Industry
Journal of the Korean Society of Safety , volume 13, issue 1, 1998, Pages 119~130
The purpose of this study is to investigate the safety consciousness of the lobours working at the ship building or repairing yard at which the industrial accidents frequently happen, and to provide the basic data required for the prevention of those accidents. This study is made by analyzing the questionnaires of 208 labours working at various ship building or repairing industries at random. This questionnaire is focused on finding the basic data for prevention of industrial accidents and getting the public opinions and proposals of labours. The results obtained by this study are as follows ; The negative estimations of the labours to the safety are cultivation of safety consciousness, the safety behavior in company, the molters of arrangement and the estimation of industrial or post arrangement. The positive ones are the arrangements of the protective tools and equipments for safety, the rule of safety regulation and the order of works, and the status of health education within company.
A Study on the Effect of Seating ＆ Lighting conditions on Work
Journal of the Korean Society of Safety , volume 13, issue 1, 1998, Pages 131~138
This field study was conducted to survey the effect of seating ＆ lighting conditions on work. The results were as follows ; Discomfortable parts of body caused by unsuitable sitting postures on work were low back 52.05%, leg 15.75%, neck 14.38% and arm 9.59%. Work conditions of sitting postures were needed arm rest, back rest of seat and adjustable seat height. Effect of work efficiency by lighting conditions were statistically significant relationship between glaring state of workstation and lighting state.
A Study on the Application of Human Factors in Construction Work
Journal of the Korean Society of Safety , volume 13, issue 1, 1998, Pages 139~146
In current domestic construction field, several factors influencing the safety for field workers are various due to the size and complexity of construction works involved. Among the factors, the age is the important one, because the average age of workers is getting older due to the 3D phenomena in construction fields. The safety for workers of all ages is important, but especially safety for the old, is more important. Thus, the fundamental techniques for placement of field workers with adequate safety corresponding to complexity and hard works are investigated through analyzing fatigue and heart rate of individual worker, especially for the old.
Ergonomic Evaluation of The POWER SURGE TOOL LINE
Seong-Rok Chang ;
Journal of the Korean Society of Safety , volume 13, issue 1, 1998, Pages 147~154
The objective of this study was to evaluate quantitatively the effects of handle types of garden tools on the ergonomic effectiveness, user satisfaction in terms of work performance, and subjective judgment of tactile feel and control. The approach was to compare garden tools with conventional wood handle and newly developed fiberglass handle, and to utilize three different tools: shovel, rake, and hoe. The hollow fiberglass handle was 12% more efficient than either the wood or solid fiberglass handle. The next important measure was the subjective ratings of the perceived exertion averaged across three different tools. The average ratings for the hollow fiberglass handle were the smallest. In conclusion, the hollow fiberglass handle showed better efficiency and better subjective acceptability for comfort, tactile feel, and especially decreased slipperiness.