• Composites Research
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• v.21 no.4
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• pp.15-21
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• 2008

Interfacial shear strength between epoxy and carbon fiber was analyzed utilizing a hemi-spherical microbond specimens adhered onto single carbon fiber. The hemi-spherical microbond specimen showed high regression coefficient and small standard deviation in the measurement of interfacial strength as compared with a droplet and an inverse hemi-spherical one. This seemed to be caused by the reduced meniscus effects and the reduced stress concentration In the region contacting with a pin-hole loading device. Finite element analysis showed that the stress distributions along the fiber/matrix interface in the hemi-spherical specimen had a stable shear stress distribution along the interface without any stress mode change. The experimental data was also different according to the kinds of loading device such as the microvise-tip and the pin-holed plate.

• Journal of Distribution Science
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• v.17 no.1
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• pp.105-115
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• 2019

Purpose - Previous research has shown that a very high level and a very low level of job scope can both be more stressful than intermediate levels of job scope. This study investigates the potential positive and negative effects of the number of accounts handled by sales personnel. The primary objective of this paper is to examine how the number of accounts salespeople handle affects their stress and performance. Research design, data, and methodology - This research conducted the data collection using a survey of salespeople in the pharmaceutical industry. I sent the survey to 420 salespeople, and received 318 usable responses. To assess measurement reliability and validity, I ran an exploratory and confirmatory factor analysis. I also employed structural equation modeling (SEM) to test all hypothesized effects in AMOS and also measured the interaction variable using Ping's (1996) approach. Results - These results show that there are linear and non-linear effects of the number of accounts handled by the salesperson on both role ambiguity and role conflict. First, the number of accounts handled by a salesperson is positively related to role ambiguity and role conflict. Second, the effect of the number of accounts handled on role ambiguity and role conflict decreases as the number of accounts handled by the salesperson increases. Third, as accounts increase from a low level, role stress increases; when the number of accounts reaches an optimal level, role stress decreases; and when the number of accounts increases to a high level, it can be detrimental to the salesperson's role stress. Fourth, while product complexity is positively related to role ambiguity, brand strength is negatively related to both role ambiguity and role conflict. Fifth, the greater the brand strength, the weaker the relationship will be between the number of accounts handled and salesperson role ambiguity. Finally, role ambiguity is positively related to salesperson performance. Conclusion - Too much and too little accounts increase the role ambiguity and role conflict of salespersons. Managers should identify the complex effect of the number of accounts handled by salespeople. Also, when products are complex, managers should provide training to eliminate any complex processes and complex information. These results suggest ways to decrease salespersons' role stress by ensuring an optimal level of the number of accounts and brand strength.

• Korean Journal of Occupational Health Nursing
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• v.14 no.2
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• pp.93-107
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• 2005

Purpose: The purpose of this study is to identify the trends of studies on work-related musculoskeletal disorder and to suggest the direction of future research. Method: 144 research thesis for a degree on work-related musculoskeletal disorder were systematic reviewed and published from Jan. 1990 to Mar. 2005. The analyzed using descriptive statistics, an actual number, percentage. Result: As its result the work-related musculoskeletal disorder research which is announced from domestic the doctorate dissertation at the 2004 year 42 the most many 144 dissertation middle most to be 129 in master degree dissertation was 15 in Ph D degree. Dissertation contents character the contents against the result relation that it analyzes especially and a condition and an obstacle was many most at 84. Research plan in most description investigation research 121 the dissertation field to be the especially public health (hygiene, industry and environment) at this 57 most many research object person distribution manufacturing industry in the research object one dissertation was many most at the 40. The tools which are used in each measurement in the question tool which it uses most the question price of land which uses the condition investigation ticket which it made from the NIOSH and the ANSI most many 33, the hazard which analyzes a work attitude in the tool which it uses the RULA was many most at 14. In the stress test tool social psychological healthy measurement PWI (Psychological Wellbeing Index) the dissertation which uses the Job Strain of the Karasek Model to be many most at 19 PWI (Psychological Wellbeing Index) 7 easy use. Work-related musculoskeletal disorder measurement hazard in physiological index and the machinery and tools which it uses there were 9 researches to use an electromyogram most plentifully. With the effect goes to a work-related musculoskeletal disorder they are 33 where the age is many most from general quality. From healthy act with the relation of smoking the year to be many from 16 dissertations. Work of the corpse an attitude (the attitude which is inappropriate) with 5 and the work market the work burglar is many most at 9, the society-support of 36 where the stress is many psychologically most, the stress and service also the most many duty discretion (authority and autonomy) is 6 at the duty demand boat song 9. The service career to be many is 22 of extraordinarily with relation of service. Conclusion: It is recommended the research which it sees being limited in only domestic thesis for a degree the international comparative study to become accomplished. It comes to think with the fact that it will be necessary to make the protocol which it conforms in the civil official guide the test researches for the protocol or arbitration program which is standardized are necessary. Prevention and the civil official of work relation bones and sinews standing total disease hazard scientific base one program is necessary with base.

• Journal of Korean Association for Spatial Structures
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• v.17 no.3
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• pp.35-43
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• 2017

The Hong Nang Sida temple is a cultural heritage that must be preserved due to the historical and cultural values that are highly evaluated in the world. The main sanctuary of Hong Nang Sida temple, presumed to have been built in 11th to 12th centuries, has been exposed in the open air for a long time after the collapse. Therefore, it is necessary to reconstruct the original shape of the Hong Nang Sida temple to reflect the original shape. To do this, it is necessary to examine the overall structure according to the restoration shape. For this purpose, this study analyzes the construction and configuration types for main sanctuary Mandapa of Hong Nang Sida temple, and conducts structural modeling according to actual and restoration plans. The structural and behavioral characteristics are analyzed by comparing stress and displacement values by measurement locations. In addition, we will examine the vertical load distribution by the layers of each wall and cobel arch of the Mandapa using the load distribution method.

• International Journal of Fluid Machinery and Systems
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• v.9 no.1
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• pp.39-46
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• 2016

A high frequency hydraulic rock drill drifter with sleeve valve is developed to use on arm of excavator. In order to ensure optimal working parameters of impact system for the new hydraulic rock drill drifter controlled by sleeve valve, the performance test system is built using the arm and the hydraulic source of excavator. The evaluation indexes are gained through measurement of working pressure, supply oil flow and stress wave. The relations of working parameters to impact system performance are analyzed. The result demonstrates that the maximum impact energy of the drill drifter is 98.34J with impact frequency of 71HZ. Optimal pressure of YZ45 rock drill is 12.8 MPa-13.6MPa, in which the energy efficiency reaches above 58.6%, and feature moment of energy distribution is more than 0.650.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.12
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• pp.686-691
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• 2016

In welded steel structures, there are many stress concentration sites such as weld beads, and welding defects are likely to occur at the welded parts. When a repeated fatigue load acts on a stress concentration site, fatigue crack occurs and propagates, leading to fatigue fracture. Therefore, it is necessary to understand fatigue life, crack initiation life, and crack propagation life in order to prevent fatigue failure. In this study, a compliance method was derived for use in the study of fatigue crack propagation characteristics. This compliance can be used for automated measurement of fatigue cracks. The compliance was calculated using an in-house FEM program for a CT specimen. The results of this calculation are presented in relation to a/W and compared with calculation results using the J integral and a program from a previous study. In addition, the strain distribution in the upward and downward directions was calculated from the center of the back face of the CT specimen. In this distribution, the strain tended to decrease from the center to the top and bottom. The compliance method was achieved from these calculations and can be used for automatic execution of crack propagation tests.

• Korean Journal of Materials Research
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• v.8 no.12
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• pp.1121-1126
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• 1998

For vacuum seated panel, stresses and displacements in the glass plate were calculated. The geometric variables for our experiment were the thickness of glass plate, the size of panel and the width of sealing line. The fracture behaviors and displacements of its under the vacuum were measured. From the measurement of strains and fracture, it was considered that the maximum stress acted at the middle of the sides of the panel. The stresses and displacement distribution of manufactured panels were greatly dependent on the width of the sealing line in the panel. The measured values are more similar to the values which were calculated from the condition of built-in edge as the width of the sealing line is larger. The measured displacement of the panel, made of 3mm thick glass plate, with size of $80\Times120\textrm{mm}^2$ and 20mm sealing line was $57\mu\textrm{m}$. This value is similar to calculated value, $54\mu\textrm{m}$, from built- in edge condition in the finite element method.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.45 no.4
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• pp.199-206
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• 2019

Objectives: In mandibular edentulism, the treatment option with a two-interforaminal implant-retained bridge and a removable partial denture is rarely evaluated in literature. The aim of this in vitro study was to evaluate the stress distribution of this treatment option by comparing it with traditional treatment options with interforaminal implants in the edentulous mandible. Materials and Methods: Two interforaminal implants were placed in a formalin-fixed cadaver mandible, and overdentures with three different types of attachments were fabricated: (1) two ball attachments and an overdenture, (2) a Dolder bar and an overdenture, and (3) screw-retained two-implant inter-canine porcelain fused to a metal bridge and an implant-assisted removable denture (IARD) with precision attachments. Three biting conditions were generated for each denture type, and the strains were documented under vertical loading of 100 N. Results: The calculated strain values from measured strains in all measurement sites and loading conditions for the screw-retained two-implant intercanine porcelain fused to a metal bridge and a cast framework partial denture with precision attachments situation were lower than in the other scenarios (P<0.05). Conclusion: Within the limitations of the present study, it can be concluded that an IARD may be a reasonable and valuable alternative to ball attachments or a bar in two interforaminal implants, especially when the patients prefer to be able to show their teeth even when they take out their removable dentures.

• Steel and Composite Structures
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• v.37 no.2
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• pp.117-136
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• 2020

Curved steel-concrete composite box girder has been widely adopted in urban overpasses and ramp bridges. In order to investigate its mechanical behavior under complicated and combined bending, shear and torsion load, two large-curvature composite box girders with interior angles of 25° and 45° were tested under static hogging moment. Based on the strain and deflection measurement on critical cross-sections during the static loading test, the failure mode, cracking behavior, load-displacement relationship, and strain distribution in the steel plate and rebar were investigated in detail. The test result showed the large-curvature composite box girders exhibited notable shear lag in the concrete slab and steel girder. Also, the constraint torsion and distortion effect caused the stress measured at the inner side of the composite beam to be notably higher than that of the outer side. The strain distribution in the steel web was approximately linear; therefore, the assumption that the plane section remains plane was approximately validated based on strain measurement at steel web. Furthermore, the full-process non-linear elaborate finite element (FE) models of the two specimens were developed based on commercial FE software MSC.MARC. The modeling scheme and constitutive model were illustrated in detail. Based on the comparison between the FE model and test results, the FE model effectively simulated the failure mode, the load-displacement curve, and the strain development of longitudinal rebar and steel girder with sufficient accuracy. The comparison between the FE model and the test result validated the accuracy of the developed FE model.

• Journal of Families and Better Life
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• v.4 no.1
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• pp.15-31
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• 1986

The purpose of this study is to investigate the relationship between the level of stress recognition of urban housewife and the method of coping, and to explore bow these factors are influenced by socio-demographic variables such as the age of housewife, level of education, status of employment, number of children, durations of marriage, types of family, religion and socio-economic status. The research was conducted on 431 housewives in Seoul in August, 1985. As for the measurement of the instrument, 48 item questionnaire made by investigator was used. The questionnaire was based upon modified and upplemented Holme & Rahe's SRRS and Bell's 18-item Questionnaire to be appropriate to Korean culture. Data were analyzed by percentage, frequency and mean, and verified significant difference by ANOVA and performed Spearman's correlation coefficient. The results of this study are as follows; 1) There is some similarity in distribution of the level of stress recognition of urban housewife. 2) the level of education and the durations of marriage have influence upon the level of stress recognition of urban housewife. In each area, there are differences among groups : age, level of education, durations of marriage, number of children and types of family in the area of education ; age, status of employment, and durations of marriage in the area of health; level of education, durations of marriage, number of children and socio-economic status in the area of finance; status of employment in the area of household work. 3) There are several methods in the method of coping to stress of housewife and the score of long-term coping method appears higher than that of short-term. 4) The level of education, number of children, religion and socio-economic status were variables to have influence on the method level of education, religion and socio- economic status were variables to have influence and in the long-term coping method level of education, number of children, religion, and socio-economic status were to have influence. 5) There is very low positive correlation between the level of stress recognition of urban housewife and the method of coping to stress( ρ=.10, P<.05). 6)In the relation between several variables in socio-demographic variables and the method to coping to stress, the lower the level of stress recognition there are negative correlation (ρ=-.28, P<.01) between religion and the method of coping and also negative correlation (ρ=-.16, P<.05) between number of children and the method of coping. There are positive correlation between socio-economic status and the method of coping.