• Journal of the Korea Safety Management & Science
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• v.14 no.2
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• pp.147-158
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• 2012

This paper aims to develop a new chain metrics for obtaining lean Overall Equipment Effectiveness(OEE) and present implementation strategy which considers the properties for Total Productive Maintenance(TPM) to reduce machine losses, Performance Analysis and Control(PAC) to reduce labor losses, Lean Production System(LPS) to reduce floor wastes, and Theory of Constraints(TOC) to minimize the problem of Capacity Constrained Resource(CCR). The study reviews the related literatures and reformulates the structure of machine losses, labor losses and field wastes. The research also develops the integrated productivity metrics according to time, units, reliability and maintainability. It is found that the study develops the actual productivity measure in terms of efficiency, effectiveness and standard productivity. In addition to that, it outlines and develops by using the integrated LPS and TPM, lean OEE measures such as Time Based Productivity(TBP), Unit Based Productivity(UBP), and Reliability & Maintainability Based Availability(RMBA). Implication examples are proposed to make it easier and available for practioners to understand the implementation strategies about TPM OEE, lean OEE and TOC OEE. Futhermore related to other studies, the research contributes to create a new chain productivity measures to clear the interrelationship concepts of productivity, efficiency and effectiveness. Moreover the paper develops the enhanced OEE measures by integration of TPM, PAC, LPS and TOC with the perspective of schedule, throughput, reliability, maintainability and availability.

• Health Policy and Management
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• v.10 no.3
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• pp.169-187
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• 2000

Cigarette smoking has been identified as the most important source of preventable morbidity and premature mortality (WHO, 1995), The prevalence of smoking among men is very high in Korea. This study estimated productivity losses due to smoking in Korea, 1997. The derivation of cost estimates for mortality, disability, hospitalization and use of physician services related to cigarette smoking is bas 어 on the calculation of attributable fractions suggested by MacMahon and Cole and Smoking-Attributable Mortality, Morbidity, and Economic Cost(SAMMEC) software. To estimate the number of deaths from neoplastic, cardiovascular, respiratory diseases associated with cigarette smoking, estimates for adults(aged 20 years and over) were based on 1997 mortality data, 1995 data on smoking prevalence from Korea Institute for Health and Social Affairs. Smoking-attributable indirect morbidity cost data were obtained from the National Federation of Medical Insurance. As the result of cost estimation, these productivity losses were 336-430 billion won. During 1997, 8,620-10,804 deaths were attributed to smoking. Cigarette smoking resulted in 133,991-169,422 Years of Potential Life Lost (YPLL) to life expectancy. For smoking -attributable indirect mortality costs, the present value of future earnings(PVFE) for the age at death are 299-384 billion won. Smoking-attributable indirect morbidity costs, the costs of lost productivity for persons who are disabled by smoking-related chronic diseases are 37-46 billion won. In this study the productivity losses due to smoking were restricted to the health effects of smoking. It is possible that these costs were underestimated with the limitation of the data. Smoking is the leading preventable cause of illness and death. The results of this study can be used as elementary data for antismoking policy.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.5
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• pp.1845-1850
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• 2015

Background: Cancer is recently one of the major concerns of the public health both in the world and Iran. To inform priorities for cancer control, this study estimated years of potential life lost (YPLL) and productivity losses due to cancer-related premature mortality in Iran in 2012. Materials and Methods: The number of cancer deaths by sex for all cancers and the ten leading causes of cancer deaths in Iran in 2012 were obtained from the GLOBOCAN database. The life expectancy method and the human capital approach were used to estimate the YPLL and the value of productivity lost due to cancer-related premature mortality. Results: There were 53,350 cancer-related deaths in Iran. We estimated that these cancer deaths resulted in 1,112,680 YPLL in total, 563,332 (50.6%) in males and 549,348 (49.4%) in females. The top 10 ranked cancers accounted for 75% of total death and 70% of total YPLL in the males and 69% for both death and YPLL in the females. The largest contributors for YPLL in the two genders were stomach and breast cancers, respectively. The total cost of lost productivity due to cancer-related premature mortality discounted at 3% rate in Iran, was US$ 1.93 billion. The most costly cancer for the males was stomach, while for the females it was breast cancer. The percentage of the total costs that were attributable to the top 10 cancers was 67% in the males and 71% in the females. Conclusions: The YPLL and productivity losses due to cancer-related premature mortality are substantial in Iran. Setting resource allocation priorities to cancers that occur in younger working-age individuals (such as brain and central nervous system) and/or cancers with high incidence and mortality rates (such as stomach and breast) could potentially decrease the productivity losses and the YPLL to a great extent in Iran.

• Journal of The Korean Society of Agricultural Engineers
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• v.64 no.3
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• pp.53-61
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• 2022

This study evaluated the impacts of subsurface drainage design, i.e., spacing and depth, on agricultural productivity and environmental sustainability in two tile-drained fields (Sites A and E) under a corn-soybean rotation in the Midwestern United States. A calibrated and validated Root Zone Water Quality Model (RZWQM) was used to simulate Nitrate-N (nitrogen) losses to tile drainage and crop yields of 30 tile spacing and depth scenarios over 24 years (1992-2015). Our results presented that the narrower and deeper the tile drains are placed, the greater corn yield and Nitrate-N losses, indicating that the subsurface drainage design may cause a trade-off between agricultural productivity and environmental sustainability. The simulation results also presented that up to about 255.7% and 628.0% increase in Nitrate-N losses in Sites A and E, respectively, far outweigh the rate of increase in corn yield up to about 1.1% and 1.6% from the adjustment of tile spacing and depth. Meanwhile, the crop yield and Nitrate-N losses according to the tile configuration differed depending on the field, and the soybean yield presented inconsistent simulation results, unlike the corn yield, which together demonstrate the heterogeneous characteristic of agro-environmental systems to a subsurface drainage practice. This study demonstrates the applicability of agricultural systems models in exploring agro-environmental responses to subsurface drainage practices, which can help guide the introduction and installation of tile systems into farmlands, e.g., orchards and paddy fields, in our country.

• Journal of Preventive Medicine and Public Health
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• v.43 no.4
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• pp.341-351
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• 2010

The purpose of this study was to estimate the socioeconomic costs resulting from alcohol drinking among adolescents as of 2006 from a societal perspective. Methods: The costs were classified into direct costs, indirect costs, and other costs. The direct costs consisted of direct medical costs and direct non-medical costs. The indirect costs were computed by future income losses from premature death, productivity losses from using medical services and reduction of productivity from drinking and hangover. The other costs consisted of property damage, public administrative expenses, and traffic accident compensation. Results: The socioeconomic costs of alcohol drinking among adolescents as of 2006 were estimated to be 387.5 billion won (0.05% of GDP). In the case of the former, the amount included 48.25% for reduction of productivity from drinking and hangover, 39.38% for future income losses from premature death, and 6.71% for hangover costs. Conclusions: The results showed that the socioeconomic costs of alcohol drinking among adolescents in Korea were a serious as compared with that of the United States. Therefore, the active interventions such as a surveillance system and a prevention program to control adolescents drinking by government and preventive medicine specialist are needed.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1996.10a
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• pp.57-60
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• 1996

It is critical that all companies improve productivity in order to maintain their international competitiveness. The productivity can be explained as a measurement of effectiveness that is calculated by "the ratio of what is produced to what is required to produce it". The goal of this paper is to enhance productivity for a small fast food company mainly through work analysis. This work analysis will help the company to downsize by improving efficiency via motion analysis and by reduction of losses via facility improvement.provement.

• Journal of The Korean Society of Agricultural Engineers
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• v.66 no.3
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• pp.15-23
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• 2024

Subsurface drainage improves crop productivity in poorly drained soils but may also substantially contribute impairment of surface water quality due to excess leaching losses of nutrients like Nitrate-Nitrogen (NO₃-N). This research presents preliminary findings from a 3-years tile depth and spacing study in Illinois state that includes three drain spacings implemented in 2 plots. We found that the plot with the narrower subsurface drainage (Case 1) exported more drainage water compared to the plot with the narrower subsurface drainage system (Case 2). The total drainage water from Case 1 plot showed 57% more compared to Case 2 plot. Whereas we observed that the plot with narrower drain spacing (Case 1) exported only 9% more NO₃-N leaching losses compared to the wider plot (Case 2). The average corn yield was observed higher in plot Case 1 compared to Case 2. Especially, we observed about 7% higher corn yield in plot Case 1 compared to Case 2 plot in the relatively dried year (2022). The preliminary findings for this study suggest that subsurface drainage systems can be optimized to reduce nutrient losses while improving the crop productivity.

• Environmental and Resource Economics Review
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• v.21 no.4
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• pp.947-980
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• 2012

This study analyzes the long-run impacts of climate change on Korean agriculture and economy. We estimate the impacts of climate change on the productivities of major agricultural products including rice, dairy and livestock using both a simulation approach and a semiparametric econometric model. The former predicts a decline in productivity while the latter predicts an increase in productivity due to climate change, especially for rice. A recursive dynamic CGE model is used to analyze the general equilibrium impacts of productivity change under the two different scenarios, derived from the two productivity analysis approaches. The loss of GDP in 2050 is 0.2% or 0.02% of total GDP depending on the scenario. It is shown that the losses in dairy and livestock sectors are larger than that in rice sector, although the losses in those two non-rice sectors have been ignored by most existing works.

• Korean Journal of Construction Engineering and Management
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• v.6 no.5 s.27
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• pp.69-77
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• 2005

Change is inevitable and is a reality of construction projects. Most construction contracts include change clauses and allowing contractors an equitable adjustment to the contract price and duration caused by change. However, the actions of a contractor can cause a loss of productivity and furthermore can result in disruption of the whole project because of a cumulative or ripple effect. Because of its complicated nature, it becomes a complex issue to determine the cumulative impact (ripple effect) caused by single or multiple change orders. Furthermore, owners and contractors do not always agree on the adjusted contract price for the cumulative Impact of the changes. A number of studies have attempted to quantify the impact of change orders on project costs and schedule. Many of these attempted to develop regression models to quantify the loss. However, regression analysis has shortcomings in dealing with many qualitative or noisy input data. This study develops ANN models to classify and quantify the labor productivity losses that are caused by the cumulative impact of change orders. The results skew that ANN models give significantly improved performance compared to traditional statistical models.

• STI Policy Review
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• v.6 no.2
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• pp.1-23
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• 2015

This study aims to contribute to the debate over the age-productivity relationships in scientific and technological research. For this purpose, we conducted an empirical experiment employing a time-series cross-section dataset derived from the KRI of the NRF containing data on individual researchers of fifty major universities in Korea covering the period of 2008-2013. This study has found that: (1) there exists an inverse U-shaped age-productivity relationship at the level of individual researchers; (2) the impact of the average age of a research group on the productivity of individual researchers varies across fields; (3) male and female researchers move along different age-productivity curves; and (4) the inverse U-shaped age-productivity relationship also holds at the level of organizations. The results suggest that the aging of researchers in Korea will soon reach the stage where serious losses in research productivity become a reality. Yet, it is not so clear whether the observed decline in the performance of older researchers is due to declining cognitive capability, which is an unavoidable result of aging, or to declining motivation, which results from an institutional system that discourages older researchers' research activities (such as reduced access to research opportunities or mandatory retirement). What is clear is that it is inevitable for the Korean science system to change the current seniority- and age-based organizational system into one of higher adaptability.