• IE interfaces
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• v.16 no.1
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• pp.16-26
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• 2003

In Korea, cooling power load, which occupies about 20% of peak load in 2000 and fluctuates depending on the popular usage of air conditioning systems, has been recently the focus of the load management. The first work of KEPCO (Korea Electric Power Corporation) to regulate cooling load as low as possible was to estimate its approximate scale and to develop the indirect methods to estimate it from the available time series data for the average hourly loads. However, KEPCO would like to have their methods improved both theoretically and practically. In this paper, we analyze their current indirect methods and detect their faults to design better indirect estimation methods. Under one of the assumptions of "no cooling load in April or May", the linear relationship between basic loads and GDP's, and the normalized seasonal factors of the Winters' multiplicative seasonal model, we provide ten indirect estimation methods in total and suggest the estimated cooling load(1988-1999) based on our various indirect methods.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.9
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• pp.4107-4118
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• 2012

This is a descriptive correlation study to identify health status and affecting factors related to job among Korean women employees. Data were obtained from women employees aged 20 to 64 using the Korean Working Conditions Survey 2006(KWCS). Stepwise multiple regression analysis using SAS version 9.1 was performed to identify affecting factors on physical and psychological health status related to job among Korean women employees. Musculoskeletal work-load was the most significant factor affecting on both physical and psychological health status. Modification of work environment to relieve musculoskeletal work-load, systemic health management and health education needs to be given to women employees who were exposed to high musculoskeletal work-load.

• Journal of Korean Society of Forest Science
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• v.87 no.2
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• pp.121-130
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• 1998

This study was carried out to investigate working time, productivity, and heart rate during thinning using chain saw in Japanese larch(Larix leptolepis) plantation site for analysis of physical work load, and to investigate maximal oxygen uptake of worker for analysis of maximal work capacity. The real working time was 366 minutes in a day ; about 192 minutes in the a.m., 174 minutes in the p.m.. The ratio of real working time per total working time was approximately 90%. The rate of moving(Mo) to real working times was 26.3, which was the largest one of work elements. Average maximal oxygen uptake, as an asset of personnel performance, was $2.42{\ell}/min$($46.5m{\ell}/kg/min$). During the real working time, average productivity, the mean rate of increase of heart rate, and the mean work load index was $2.62m^3/hr$, 93.2%, and 41.9%, respectively.

• Transactions of Materials Processing
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• v.8 no.1
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• pp.101-107
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• 1999

The upset forging stage is the initial work in the forging process. It is used to remove the segregation and cavities of the ingot. Specially in handling large sized ingot, an improper upset forging can cause serious surface tearing. However, there is no detail reference for stable upset forging work. To resolve this difficulty, we studied several factors such as upset forging time, temperature varation of ingot, damage, load and stain rate etc., by using the rigid-plastic finite element approach available in the DEFORM code. Numerical simulation results indicated that: the load value of upset forging works shows severe decreasing trend at a certain point, same as strain rate. Also defects were found to be concentrated around the upper and lower portions of the ingot. With these results, we can estimate a guideline for stable upset forging work.

• Journal of Agricultural Extension & Community Development
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• v.4 no.2
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• pp.415-421
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• 1997

The objectives of this study were 1) to evaluate the first year of localization of agricultural extension in Korea, 2) to present the development directions and implications of agricultural extension service in the next year of localization. The major results and implications were as follows. 1. The positive changes in localization were to establish local special projects and to work in agricultural extension without personnel changes. 2. The negative changes in localization were increase of unnecessary work load and decrease of morale because of lowered status. 3. The development directions were to cut back unnecessary work load, to rearrange an office, and to return to the national status of extension personnels.

• Fibers and Polymers
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• v.6 no.4
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• pp.339-342
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• 2005

In this paper, a hand-operating method (tiled test method) of the wool-blending sample is made out, and make use of the method, the test of wool-blending bundle in different blending ratio is accomplished. According to the test data, the synthesis method of the stretch curve is worked out and the synthesis software for the typical stretch curve of wool-blending bundle is designed. Through laboratory hand-operating method, the blending fasciculus applying to fiber bundle test can be obtained in a short time. Calculation for sampling is accomplished in the article. We bring up 9 new signs to describe the characteristics of the curve behind peak for the first time: elongation behind peak (HE), elongation percentage behind peak (HEP), relative elongation rate behind peak (RHE), total break work $(W_a)$, break work behind peak (HW), break work coefficient behind peak (HWC), elongation percentage of half-load behind peak (HEL), load percentage of half-elongation behind peak (HLE), break efficiency behind peak (HEC).

• IE interfaces
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• v.11 no.2
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• pp.177-190
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• 1998

The work-order performs an important role in make-to-order production. The development of work-order system in this production is more complex than work-order system in planing production. To construct work-order system, load of directors for work-order must be decreased, and production management between scheduling of master plan and current workshop conditions must be considered. In this study, we grasped troubles in present work-order system and flows of information for work order. Using these results are made database schemas and data flow diagrams for effective development of work-order system. And then, for successful establishment of work-order system and actual use of directors, we considered systematic and easy user-interface. For a case study, development procedures of work-order system are presented for plant factory.

• Journal of the Korean Society of Safety
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• v.32 no.3
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• pp.15-20
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• 2017

This study presented the strength of the materials and parts for smart distribution board fabrication, and developed a work operation process chart for smart distribution board fabrication. This work operation process chart for smart distribution board fabrication complied with SPS-KEMC regulations, and the applicable range and object are less than 1,000 V and 1,000 Hz for the AC distribution board and less than 1,500 V for the DC distribution board. The power supply is 3 phase 4 wires ($3{\Phi}$ 4W), divided into a single phase circuit and a 3 phase circuit. In addition, the circuit was configured so that the leakage current flowing through the distribution line of the load could be monitored in real time by using the sensor module installed at the rear end of the circuit breaker. Therefore, the administrator can easily find the risk factor of the load since engineer can check the leakage current of each distribution line. In addition, if a leakage current greater than standard value flows, it is possible to generate an alarm against a short circuit and cut off the leakage current. The work operation process chart for the smart distribution board fabrication consists of the following steps: raw and subsidiary materials, sheet metal work, tube making, welding, painting, busbar fabrication, assembly and wiring, product inspection, shipment, etc. Moreover, symbols, ${\Delta}$, ${\nabla}$, ${\bigcirc}$, ${\Rightarrow}$, etc. were used according to the type of work and work progress so that workers can easily understand the progress of the work.

• Journal of agricultural medicine and community health
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• v.22 no.1
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• pp.49-59
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• 1997

Backgrounds : There has been many studies investigating the causes of farmers' syndrome. In some studies, psychologic stress is related to farmer's syndrome. And the diagnostic criteria of farmer's syndrome is similar to those of generalized anxiety disorder. So we carried out this study to investigate the psychiatric causes of farmers' syndrome. Methods : This study was done in some rural and urban areas of Kyoungsangnam Province, July, August, October and November of 1996. Those who came to free medical service and completed interview, medical examination and laboratory examination and 20-59 years old were 150 persons. And those who came to health center for health examination and completed only interview and 20-59 years old were 94 persons. The questionnaire was composed of sociodemographic factors, health risk factors, farmer's syndrome, work load, BEPSI(inventory to measure stress), Spielberger's state-trait anxiety inventory, self-rating depression scale. To examine statistical significance, we used X2-test, Mantel-Haenszel test for linear association, t-test, ANCOVA, correlation, multiple regression, logistic regression. Results : The prevalence of farmer's syndrome, adjusted for age and sex with population of Kyungsangnam Province of 1993 was 208 per 1,000(90 per 1,000 in men and 329 per 1,000 in women). In bivariate analysis, farmer's syndrome was significantly related to age, sex, job, income, smoking, alcohol drinking, work load, BEPSI, state anxiety, trait anxiety, depression, body mass index, Hwa-Byung, hypertension, anemia. However, when age and sex were adjusted, job was not significantly related to farmer's syndrome. The score of farmer's syndrome was significantly related to age, sex, work load, BEPSI, trait anxiety by multiple regression. Farmer's syndrome was significantly related to increasing age(odd ratio 1.079, 95% C.I. 1.060 - 1.099), sex(odds ratio of male 0.434, 95% C.I. 0.349 - 0.540), and BEPSI(odds ratio 1.231, 95% C.I. 1.148 - 1.320) by logistic regression. Results of logistic regression analysis of the component symptoms of farmer's syndrome were as follows. Shoulder stiffness was significantly related to increasing age, female sex and BEPSI. Lumbago was significantly related to increasing age, female sex and trait anxiety. Numb limbs and nocturia was significantly related to increasing age and female sex. Breathlessness was significantly related to work load, sleeplessness was significantly related to depression, dizziness was significantly related to job and state anxiety, and abdominal fullness was significantly related to female sex. Conclusion : Farmers' syndrome was related to work load, but was more related to psychiatric factors such as BEPSI and trait anxiety. And the occupation was not risk factor of farmers' syndrome in this study, so further study is needed to investigate the cause of farmers' syndrome.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.37 no.4
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• pp.705-716
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• 2017

As many environmental pollution problems have arisen, various studies related to the environmental evaluation have been carried out in the construction industry. However, there is no methodology for estimating the environmental load quickly for design alternatives of civil facilities in the design phase. This study aim to establish criteria of works information and designed parts which can efficiently estimate environmental loads of PSC beam bridge based on standard quantity at the early design phase. For this purpose, a detailed environmental loads database was constructed by performing Life Cycle Assessment (LCA) based on detailed design data of 25 bridges. In addition, major work with high impact on environmental load were selected, and the analysis of characteristics of environmental load according to the required materials and 8 impact categories were conducted. As a result, the superstructure accounted for 42.91%. In the superstructure, remicon of the material base and PSC beam work occupied 53.13% and 31.25%. In the substructure, remicon, rebar, and cement, which are material base, accounted for more than 93%. It is expected that this major work and material information for each part of bridge can be utilized in the construction of the model, which can estimate the approximate environmental load, reflecting the characteristics of the structure in the design phase.