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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 17, Issue 4 - Dec 2002
Volume 17, Issue 3 - Sep 2002
Volume 17, Issue 2 - Jun 2002
Volume 17, Issue 1 - Mar 2002
Selecting the target year
Study on Evaluating the Damage Fracture Behavior of the Carbon Fiber Reinforced Composite Material by Acoustic Emission Characteristics
Kwon, Oh-Hyun ;
Journal of the Korean Society of Safety , volume 17, issue 1, 2002, Pages 1~5
An approach for the damage of delamination which is the major concern during mechanical working for composite laminate material is proposed based on linear elastic fracture mechanics. This paper presents method evaluating of damage crack length using by average thrust force with AE characteristics. Also, the relations of AE characteristics are obtained from delamination damages. We found the onset ply of the delamination and a critical energy release rate and expressed a stress intensity factor by AEcount equation.
A Study on the Impact Behavior and Damage of Laminated Composite Plates Subjected to the Low-Velocity Impact
Ahn, Kook-Chan ; Kim, Kyu-Su ; Park, Seung-Bum ; Hwang, Byung-Sun ;
Journal of the Korean Society of Safety , volume 17, issue 1, 2002, Pages 6~10
This paper presents the impact behavior and damage of laminated composite plates subjected to low-velocity impact. For this purpose, a pendulum impact test for impact behavior and C-scan for impact damage are done. Test materials are carbon/epoxy laminated composite plates and stacking sequences
Evaluation of Circle Machining Surface Roughness on the Process Conditions using Neural Network
Sung, Baek-Sup ; Kim, Ill-Soo ; Cha, Yong-Hun ;
Journal of the Korean Society of Safety , volume 17, issue 1, 2002, Pages 11~17
The purpose of this study was to present the method to choose the optimization machining condition for the wire electric machine. This was completed by examining the ever-changing quality of the material and by improving the function of the wire electric discharge machine. Precision metal mold products and the unmanned wire electric discharge machining system were used and then applied in industrial fields. This experiment uses the wire electric discharge machine with brass wire electrode of 0.25mm. To measure the precision of the machining surface, average values are obtained from 3 samples of measures of center-line average roughness by using a third dimension gauge and a stylus surface roughness gauge. In this experiment, we changed no-node voltage to 7 and 9, pulse-on-time to
, pulse-off-time to
, and experimented on wire tension at room temperature by 1000gf, 1200gf, and 1400gf, respectively.
Analysis on the Fatigue Fracture Surface of Gas Piping Material using the X-Ray Fractography
Lim, Man-Bae ;
Journal of the Korean Society of Safety , volume 17, issue 1, 2002, Pages 18~24
This study verified the relationship between fracture mechanics parameters(
) and X-ray parameters (
) for G365 steel at elevated temperature up to
. The fatigue crack propagation test were carried out and X-ray diffraction technique according to crack length direction was applied to fatigue fractured surface. The residual stress on the fracture surface was found to increase in low
region, reach to a maximum value at a certain value of
and then decrease. Residual stress was independent on stress ratio by arrangement of
and half value breadth was independent by the arrangement of
. The equation of
was established by the experimental data. Therefore, fracture mechanics parameters could be estimated by the measurement of X-ray parameters.
The Mechanical Properties Evaluation on Lay-up Orientation Effect of CFRP Laminate Composite with the Hole Notch
Tae, Young-Il ; Yun, Yu-Seong ; Kwon, Oh-Heon ;
Journal of the Korean Society of Safety , volume 17, issue 1, 2002, Pages 25~32
The tensile tests for [0/90]s, [90/0]s, and
laminate composite were accomplished with acoustic sensor and failure processes were recorded by a video camera in real time. Also SEM examinations for fracture and side surface were carried out. The purpose of study is estimation of the failure mechanism and the mechanical properties effected by lay-up orientation for CFRP laminate composite with the hole notch. From the results, mechanical properties were obtained and they are similar between two kinds of cross-ply orientation in CFRP laminate composites, but not on
. And accordings to increasing the load, accumulate AE count was increased, regardless of lay-up orientation. Futhermore, failure mechanism was described by a video monitoring and SEM.
A Study on the Fatigue Crack Growth Behavior in Residual Stress Field of the SS41 Welding Material
Choi, Byung-Ki ;
Journal of the Korean Society of Safety , volume 17, issue 1, 2002, Pages 33~38
SS41 material is welded automatically and is investigated some effects of the welding residual stress on the growth and propagation of fatigue crack, so as to study the fatigue behaviour in the welding residual stress field. The summarized results are as follows; 1) In case of the load amplitude is constant, as the stress ration is changing to 0.1, 0.33 and 0.5 the propagation life is constant but the initiation life decreases. And than, when maximum load or minimum load is constant, s the stress ration increases the initiation life and propagation life. 2) It was shown that the fatigue crack propagation ratio da/dn was almost constant regardless of the stress ratio change at constant load amplitude and that the larger stress ratio, the slower was the fatigue crack propagation ratio. 3) The opening ratio U is influenced by
but it isn't only the function of
because data range is very large. 4) The fatigue life of the specimens on tensile compressive residual stress field was decreased and increased respectably more than that of the base metal.
On Evaluation of CFRP Composite Laimates Using Ultrasonic Transducers with Polarization Direetion
Ra, Seung-Woo ; Im, Kwang-Hee ; Yang, In-Young ;
Journal of the Korean Society of Safety , volume 17, issue 1, 2002, Pages 39~44
This paper shows error in the polarization direction on ultrasonic transducers how sensitive the shear ultrasonic waves are to a little misoriented plies according to the angle variation of shear ultrasonic waves
. Also, it is shown that shear waves, particularly the transmission mode with the transmitter and receiver perpendicular to cach other, have high sensitivity for detecting anomalies in fiber orientation and ply layup sequence that may occur in the manufacturing of composite laminates. Experimental results are agreed with a modeling solutions which was based on decomposition of shear wave polarization vector as it propagates through the composite laminates. This wave appeared considerably to be sensitive to CFRP composites to thickness direction along in-plane fibers.
An Empirical Study on Malfunction of the Earth Leakage Circuit Breaker
Kim, Tae-Man ; Kwon, Yong-Jun ; Kee, Do-Hyung ;
Journal of the Korean Society of Safety , volume 17, issue 1, 2002, Pages 45~53
The purpose of this study was to investigate effect of electrical noise on malfunction of the earth leakage circuit breaker. A three-way experiment for studying its malfunction was conducted, in which electrical products such as radio, alternating current are welder and cellular phone, distance from the earth leakage breaker to electrical products, and whether or not the earth leakage breaker is contained is contained in the steel box were employed as experimental variables. Eleven earth leakage breakers frequently used in real situations were tested in each experimental treatment. The electrical products were used for generating electrical noise that is known to be able to cause malfunction of the earth leakage breaker. The results showed that except a case for one of the 11 earth leakage breakers when the radio made by M company was located 30 cm ahead of the breaker, malfunction did not occur in any other experimental treatment. Consequently, it is suggested that the breaker should be normally used for preventing electricity-related accidents without fear of its malfunction in industrial sites.
Study on Adsoption Characteristics of Tharonil on Activated Carbon Fixed Bed
Lee, Jong-Jip ; Yu, Yong-Ho ;
Journal of the Korean Society of Safety , volume 17, issue 1, 2002, Pages 54~60
To obtain the breakthrough characteristics for the design of fixed bed adsorption plant, adsorption experiment on granular activated carbon was performed with tharonil in the fixed bed. The pore diffusivity and surface diffusivity of tharonil estimated by the concentration-time curve and adsorption isotherm were
, respectively. From comparison of the pore diffusivity and surface diffusivity, it was found that surface diffusion was controlling step for intrapaticle diffusion. The breakthrough curve predicted by constant pattern-linear driving force model were shown to agree with the experimental results. The surface diffusivity and film mass transfer coefficient had no effect on the theoretical breakthrough curve but the adsorption isotherm had fairly influence on it. Appearance time of breakthrough curve is faster with the increase flow rate and inflow concentration of liquid. The utility of granular activated carbon is enhanced with the increase of bed height and with the decrease of inflow rate.
A Toxicity Evaluation on the Toxic Gases Released from Interior Upholstery Fires
Ham, Sang-Keun ; Kim, Hong ; Gang, Yeong-Gu ; Kim, Dong-Hyeon ; Lee, Yeong-Seop ;
Journal of the Korean Society of Safety , volume 17, issue 1, 2002, Pages 61~67
The toxic gases released from a fire can be classified as asphyxiants such as carbon monoxide, and irritants such as hydrochloric acid, etc. It is recognized that the combustion characteristic of interior upholstery is one of the important factors to determine the severity of indoor fires. In this study, several of the mostly used interior upholsteries including wallpaper, veneer board, curtain and floor cover, were selected to be evaluated by using the method of NES 713. The toxicity indices of the experimental samples, which indicate their toxic potentials in a fire were lowered in the order of Wallpaper (Flame Retardant) 8.5>Floor Cover(Hard) 4.8>polyurethane 4.3>Floor Cover(Soft) 3.5>PVC 2.8> Veneer Board 2.3> Floor Cover(flame retardant) 2.1>Wallpaper(Promulgation) 1.4>Curtain 0.9. It is concluded that, among all the tested upholsteries, wallpaper (flame retardant) would release the largest quantity of Toxic gases in a fire.
A Study on Safety Cos Estimation Using Process Risk Assessment for Polyol Process
Lee, Jun-Suk ; Lee, Young-Soon ; Park, Young-Ku ;
Journal of the Korean Society of Safety , volume 17, issue 1, 2002, Pages 68~71
A research on accident loss calculation for polyol process without safety management activities, and safety cost estimation using process risk assessment has been implemented. In order to estimate a magnitude of loss, accident scenarios were made by combining result made from HAZOP Study method with accident possibility analysis results implemented with FTA. Also effect assessment was implement for accident consequence of each scenario. And minimum possible loss cost has been calculated when safety investment do or not. Result from cost-benefit analysis was shown as approximately \335 billion(=USS44,000 billion), as cost after subtracting safety management cost from minimum possible loss cost.
A Study on Development of Lightweight Aggregate Using Industrial Wastewater Sludge
Ko, Young-Min ; Lee, Nae-Woo ; Choi, Jae-Wook ; Woo, Hee-Chul ; Shin, Hack-Gi ;
Journal of the Korean Society of Safety , volume 17, issue 1, 2002, Pages 72~78
Among the disposal techniques of inorganic wastewater sludges from industries most of sludges were dealed with buring underground inefficiently. But we have tried to recycle the resources that exhausted inorganic sludges were properly blended to certain ratioes to make lightweight aggregate, that means manufacturing of it can be possible through blending of various components, drying, sintering, cooling and crushing to certain sizes that are needed by consumers. As disposal method of inorganic wastewater sludge is changed to environmentally fraternative method, this method could be very useful to make lightweight aggregates for decoration of building and the other so many purposes of those usages. That could be economically useful due to expected income for buring costs of ordinary disposal method form industries and sales income after manufacturing it. The second important profit is saving foreign currency from purchasing self-developed lightweight aggregate insteas of importing expensive foreign product. This product will be also very impressive to user because of the fraternative lightweight to be composed of apatite structure that is important part of human body.
Ground Response Analysis of the Cmpressor Station for Installation of Seismic Instrument
Kwon, Ki-Jun ; Kim, Yong-Gil ;
Journal of the Korean Society of Safety , volume 17, issue 1, 2002, Pages 79~86
In the case of earthquake, it is necessary to install earthquake instruments and to measure the ground motions for stable gas supply and restoration in case of supply suspension. Because each point in the site of the gas facilities has different characteristics of ground motion, it is recommended to measure at the point where the ground motion is representative. In this paper, ground motion analysis and noise pattern analysis are carried out to select suitable point for the installation of earthquake instruments and to set of dynamic range of sensors.
Analysis of Efficient Investment for Apartment Gang Form Work by FTA Technique
Son, Ki-Sang ; Kim, Si-Ok ;
Journal of the Korean Society of Safety , volume 17, issue 1, 2002, Pages 87~93
In this thesis using FTA technique, the author proposes a new method of analysis of some accidents in construction work. Some efficient plans of safe facility investment are made out. For this study, I referred to 'The Death Accident in Construction Works', which have been published by Korea Industrial Safety Corporation from 1993 to 1999 for 6 years. I selected some of apartment constructions which have caused many deaths for the purpose of analysis in the study. I found that the concrete work using ferro-deck takes more deaths than the conventional construction. After finding this, I selected GANG FORM works using ferro-concrete which is the most widely used but causes many accidents. On the basis of the classification, I try to do some quantitative analyses by adding the death frequency and material factors. In order to draw up the most efficient investment plan, it is imperative that FT diagram be made out and that factors. In order to draw up the most efficient investment plan, it is imperative that FT diagram be made out and that minimal Cut Set be needed. It requires a great deal to labor and time to get Minimal Cut Set. The Minimal Cut Set which is formed of these process is the main factor to analyze disaster in the work. It is desirable that we add calculated percentage of accidents to these factors to these factors in value order, that is to say, from the high cost to low cost.
Categorical Analysis for the Factors of Incustrial Accident Cases
Jhee, Kyung-Tek ; Song, Young-Ho ; Chung, Kook-Sam ;
Journal of the Korean Society of Safety , volume 17, issue 1, 2002, Pages 94~98
This study aimed to search for the fundamental accident causes using a categorical analysis, a kind of statistical methods. As the analysis methods, correlation analysis, independence test and logistic regression analysis were used. And the SPSS package, a general-purpose mathematical library, was used to obtain statistical characteristics. As the result of this study, the accident causes associated with factor of 'lost working days' were factors such as 'employed periods', 'sex', 'type of accident', 'month'. In case of applying independence test method, the most important cause was the factor of 'month'. In case that logistic regression analysis method was applied, the cause contributed to the increase structure'. 'less than 6 month'. On the basis of these results, the plan for accident prevention and the proper investment for accident prevention expenditure could be carried out in each workshop.
In-Plane Extensional Vibration Analysis of Curved Beams using DQM
Kang, Ki-Jun ; Kim, Byeong-Sam ;
Journal of the Korean Society of Safety , volume 17, issue 1, 2002, Pages 99~104
DQM(differential quadrature method) is applied to computation of eigenvalues of the equations of motion governing the free in-plane vibration for circular curved beams including mid-surface extension and the effects of rotatory inertia. Fundamental frequencies are calculated for the members with various end conditions and opening angles. The results are compared with numerical solutions by other methods for cases in which they are available. The differential quadrature method gives good accuracy even when only a limited number of grid points is used.