• Journal of Biosystems Engineering
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• v.28 no.6
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• pp.537-544
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• 2003

The objectives of this study were to investigate the failure characteristics of a total of 90 parts of tractor driveline, and to predict their average annual demands required to perform the after-sales service. The failure characteristics such as failure mode, mean time between failures, characteristic life and reliability were analyzed using the data collected through the experienced mechanics at the part centers of the tractor manufacturers. The analysis was based on the assumption that the failure distribution follows the Weibull distribution. The average annual demands were also predicted for the replacement parts using the mean time between failures and the renewal theory based on the Weibull distribution. The results of the study revealed that the driveline parts failure was mostly from wearout and their average characteristic life is about 1.760 hours. The estimated mean time between failures was in a range of 670∼3,740 hours and reliability in a range of 40∼60％. The annual replacement demands were in a range of 4∼45 for a service of 100 tractors.

• Safety and Health at Work
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• v.5 no.3
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• pp.165-167
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• 2014

The Dutch construction industry has introduced a compulsory preemployment medical examination (PE-ME). Best-evidence contents related to specific job demands are, however, lacking and need to be gathered. After the identification of job demands and health problems in the construction industry (systematic literature search and expert meeting), specific job demands and related requirements were defined and instruments proposed. Finally, a work ability assessment was linked to the instruments' outcomes, resulting in the modular character of the developed PE-ME. Twenty-two specific job demands for all Dutch construction jobs were identified, including kneeling/squatting, working under time pressure, and exposure to hazardous substances. The next step was proposing self-report questions, screening questionnaires, clinical tests, and/or performance-based tests, leading to a work ability judgment. "Lifting/carrying" is described as an example. The new modular PE-ME enables a job-specific assessment of work ability to be made for more than 100 jobs in the Dutch construction industry.

• Earthquakes and Structures
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• v.9 no.3
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• pp.673-698
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• 2015

This paper investigates inelastic seismic demands of the normal component of near-fault pulse-like ground motions, which differ considerably from those of far-fault ground motions and also parallel component of near-fault ones. The results are utilized to improve the nonlinear static procedure (NSP) called Displacement Coefficient Method (DCM). 96 near-fault and 20 far-fault ground motions and the responses of various single degree of freedom (SDOF) systems constitute the dataset. Nonlinear Dynamic Analysis (NDA) is utilized as the benchmark for comparison with nonlinear static analysis results. Considerable influences of different faulting mechanisms are observed on inelastic seismic demands. The demands are functions of the strength ratio and also the pulse period to structural period ratio. Simple mathematical expressions are developed to consider the effects of near-fault motion and fault type on nonlinear responses. Modifications are presented for the DCM by introducing a near-fault modification factor, $C_N$. In locations, where the fault type is known, the modifications proposed in this paper help to obtain a more precise estimate of seismic demands in structures.

• Korean Journal of Occupational Health Nursing
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• v.24 no.2
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• pp.132-141
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• 2015

Purpose: The purpose of this study was to investigate the relationships between psychosocial working conditions and psychological well-being depending on the gender among Korean interactive service workers. Methods: This study was a secondary analysis of the data extracted from the 2011 Korean Working Conditions Survey. For the present analysis, 15,669 workers who interact with others at work were selected. Based on the existing literature, a set of variables was chosen from the KWCS. Psychological well-being was measured using the WHO-5 well-being index. Results: The prevalence of poor psychological well-being was significantly higher among men (43.1%) than women (39.6%). Women were more likely to be exposed to demands for hiding emotions, bullying, and discrimination, whereas men were more likely to be exposed to psychological job demands, cognitive demands, demands for responsibility, role conflict and long working hours. Most factors were associated with poor well-being among women and men except demands for hiding emotions, skill discretion and development, physical violence, and sexual harassment. Conclusion: Based on these results, some practical suggestions are offered to help interactive service workers adjust to their duties.

• Structural Engineering and Mechanics
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• v.69 no.1
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• pp.95-104
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• 2019

The Standard ASCE 61-14 proposes the Substitute Structure Method (SSM) as a Nonlinear Static Procedure (NSP) to estimate nonlinear displacement demands at the center of mass of piers or wharves under seismic actions. To account for bidirectional earthquake excitation according to the Standard, results from independent pushover analyses in each orthogonal direction should be combined using either a 100/30 directional approach or a procedure referred to as the Dynamic Magnification Factor, DMF. The main purpose of this paper is to present an evaluation of these NSPs in relation to four wharf model structures on soil conditions ranging from soft to medium dense clay. Results from nonlinear static analyses were compared against benchmark values of relevant Engineering Design Parameters, EDPs. The latter are defined as the geometric mean demands that are obtained from nonlinear dynamic analyses using a set of 30 two-component ground motion records. It was found that SSM provides close estimates of the benchmark displacement demands at the center of mass of the wharf structures. Furthermore, for the most critical pile connection at a landside corner of the wharf the 100/30 and DMF approaches produced displacement, curvature, and force demands that were reasonably comparable to corresponding benchmark values.

• PNF and Movement
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• v.10 no.3
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• pp.53-66
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• 2012

Purpose : This research has been studied physical therapy curriculum according to the demands of the medical institution. Methods : The subjects of this study were 88 physical therapists. The subjects were divided by OS(n=41) and NS(n=47) group. The results of research were analyzed using independent t-test with average and standard deviations as the statistical methods for data analysis. Results : the results of the study were as follow : First, it was needed on the development planning for physical therapy curriculum according to the demands of the medical institution. Second, tests of independent t-test were a statistically significant difference between OS and NS group on the demands of the medical institution. Third, it was needed that time tables on physical therapy curriculum were partially regulated by the demands of the medical institution. Conclusion : We suggest to change the curriculum of physical therapy. It is more accurately reflected the rigor of the high-quality education preparation needed for current and future practice.

• The Journal of Korean Academy of Prosthodontics
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• v.33 no.1
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• pp.156-163
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• 1995

A total of 2,510 police personnel aged 20-59 were examined to determine the prosthodontic demands. The results were as follows. 1. Prosthodontic demands increase with aging. 2. Periodontic problem is the major cause of the prosthodontic needs in old personnel. 3. Trauma is the more popular cause of the prosthodontic need than periodontal problem in policeman. 4. The major cause of the untreatment is the lacks of time. 5. The younger persons have more fear of dental treatment. 6. Prostodontic demands show declining trends.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.18 no.36
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• pp.113-120
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• 1995

Much of the past work regarding repairable item stockage has concentrated on the development of models and policies for systems in steady state. However, there are important situations in which the transient behavior is most important. A dramatic example of this is the potential dynamic behavior exhibited by demands and service in the deployment of an Air Force squadron at the onset of a conflict. The purpose of this paper is to derive some probability distributions necessary for providing an integrated approach for a multi-echelon inventory system with nonstationary demands and service rates.

• Earthquakes and Structures
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• v.1 no.1
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• pp.69-91
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• 2010

Current seismic design codes do not contemplate explicitly some variables that are relevant for the design of structures subjected to ground motions exhibiting large energy content. Particularly, the lack of explicit consideration of the cumulative plastic demands and of the degradation of the hysteretic cycle may result in a significant underestimation of the lateral strength of reinforced concrete structures built on soft soils. This paper introduces and illustrates the use of a numerical performance-based methodology for the predesign of standard-occupation reinforced concrete ductile structures. The methodology takes into account two limit states, the performance of the non-structural system, and in the case of the life safety limit state, the effect of cumulative plastic demands and of the degradation of the hysteretic cycle on the assessment of structural performance.

• Structural Engineering and Mechanics
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• v.41 no.2
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• pp.243-262
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• 2012

Nonlinear static analysis as an essential part of performance based design is now widely used especially at design offices because of its simplicity and ability to predict seismic demands on inelastic response of buildings. Since the accuracy of nonlinear static procedures (NSP) to predict seismic demands of buildings affects directly on the entire performance based design procedure, therefore lots of research has been performed on the area of evaluation of these procedures. In this paper, one of the popular NSP, FEMA356, is evaluated and compared with modal pushover analysis. The ability of these procedures to simulate seismic demands in a set of reinforced concrete (RC) buildings is explored with two level of base acceleration through a comparison with benchmark results determined from a set of nonlinear time history analyses. According to the results of this study, the modal pushover analysis procedure estimates seismic demands of buildings like inter story drifts and hinges plastic rotations more accurate than FEMA356 procedure.