• Journal of Korean Society of Industrial and Systems Engineering
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• v.39 no.3
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• pp.109-117
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• 2016

Recently, corporate environment is faced with uncertainty that did not suffer in the past. In addition, as the supply chain was expanded and lengthened, the flow of information and material was complicated. Increase in complexity which amplifies the variability of the individual steps in supply chains further adds to the uncertainty. The bullwhip effect that refers the phenomenon where order variability increases as the orders move upstream in the supply chain became serious. The bullwhip effect is more and more important especially for the enterprise in the supply chain. So, there are many studies now since it was observed about 100 years ago. The aim of this paper is to analyze how to solve the bullwhip effect by using TRIZ (Teoriya Resheniya Izobretatelskikh Zadach). TRIZ is one of the most famous tools for creative solving that applied in many fields ranging from management as well as engineering. Among problems, the dilemma needs creative solutions that require handling the contradictions inherent in that. Among various kinds of problem solving techniques, TRIZ provides the concept of physical contradiction as a common problem solving principle. This study provides a simple process of solving problem explains a case of solving problem in the management field and shows the availability of theory in the inventory control. In accordance with the proposed solving process, the paper analyzes the bullwhip effect by applying the TRIZ tools and then identifies the solution directions. Next, the current studies are classified by the above analysis and important managerial concepts are proposed. Lastly, directions for future research on this area are suggested.

• Journal of Korean Society for Atmospheric Environment
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• v.27 no.5
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• pp.580-602
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• 2011

Volatile organic compound (VOC) emissions in the 2007 CAPSS (Clean Air Protection Supporting System) emissions inventory are chemically speciated for the SAPRC99 (Statewide Air Pollution Research Center 99) mechanism, following the Source Classification Code (SCC) matching method to borrow the U.S.EPA's chemical speciation profiles. CMAQ simulations with High-order Direct Decoupled Method (HDDM) are in turn applied to evaluate uncertainty in the method by comparing the simulated model VOC species to the observations in the Seoul Metropolitan Area (SMA) for a 2007 June episode. Simulations under-predicted ALK1 to ALK4 in SAPRC99 by a factor of 2 to 5 and over-predicted ALK5 by a factor of 7.5 while ARO1, ARO2, OLE1, and ethylene (ETH) are comparable to the observations, showing relative difference by 10 to 30%. OLE2 emissions are roughly 4 times overestimated. Emission rates for individual VOC model species are revised referring to the ratio of simulated to observed concentrations. Impact of the VOC emission changes on the overall ozone prediction was insignificant for the days of which 1-hr maximum ozone are lower than 100 ppb. However, simulations showed ozone difference by 5 to 10 ppb when high ozone above 120 ppb was observed in the vicinity of Seoul. This result suggests that evaluations on individual model VOC emissions be necessary to lead ozone control plans to the right direction. Moreover, the simulated ratios of ARO1 and ARO2 to $NO_x$ are roughly 50% lower than the observed ones, which imply that adjustment in $NO_x$ and VOC emission rates may be required to mimic the real VOC/$NO_x$ condition over the area.

• Korean Journal of Agricultural Science
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• v.43 no.3
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• pp.299-319
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• 2016

The National Forest Inventory (NFI) is important for providing fundamental data for basic forest planning and the establishment of forest policies for the purpose of implementing sustainable forest management. The purpose of this study is to present the development of Korea's NFI including legal basis, sampling design, and measured variables and to review the usage of NFI data. The survey methods and forestry statistics among the Unites States, Canada, Japan, China, and European countries were briefly compared. Total 140 publications utilizing NFI data between 2008 and 2015 were categorized with 15 subjects. Korea has conducted the NFI 6 times since 1971, but only the $6^{th}$ NFI is comparable with the fifth, the previous NFI, because the permanent sampling plots have been shared between the periods. The Korean Forestry Statistics contains only half as many variables as that of advanced countries in Forestry. More researches were needed to improve consistent measurement of diverse variables through implementation of advanced technologies. Additional data for Forest Health Monitoring since the NFI $6^{th}$ must be under quality control which will be an essential part of the inventories for providing the chronological change of forest health.

• Journal of agricultural medicine and community health
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• v.36 no.3
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• pp.157-166
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• 2011

Objectives: Anxiety and depression are known to be associated with hypertension, and blood pressure can vary spontaneously throughout the day. The aim of this study was to evaluate anxiety, depression and 24-hour ambulatory blood pressure (24-h ambulatory BP) in employees at their worksite. Methods: A total of 107 volunteers among 136 employees at a hotel in Gyeongju, Korea were enrolled in this study between December 2009 and March 2010. The Beck Anxiety Inventory (BAI) and the Beck Depression Inventory (BDI) were used to assess anxiety and depression, respectively. Blood pressure was measured using a 24-h ambulatory BP monitoring system. Results: No significant differences in either BAI or BDI scores were found when hypertensive individuals were compared to normotensive individuals. The frequency of diastolic non-dipper was significantly higher in individuals with depressive symptoms compared to those without (p<0.05). Depression was significantly associated with diastolic non-dipper (OR: 6.85, 95% CI: 1.50-30.01). Conclusions: The results of this study indicate that depression should be considered when deciding upon blood pressure control regimens, and appropriate additive psychotherapy may be beneficial in the treatment of hypertensive patients.

• Quality Improvement in Health Care
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• v.1 no.2
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• pp.60-72
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• 1994

Background: The number of outpatients visiting large university teaching hospitals has increased drastically with the introduction of a nationwide health care insurance in 1989 and the improvement of the socio-economic status of the population. This resulted in long waiting times for services, particularly prescribed drugs, which have been patients' chief complaints. Hospitals have tried to solve the problem with limited success because their approach lacked comprehensive research. The objective of this study is to investigate associations between waiting times and variables defining a total work system. Methods: Data for the outpatient pharmacy department in a tertiary care university teaching hospital located in Seoul was analyzed to achieve the study objective. Associations of pharmacy system variables -- work load, work force, pharmacist work schedule, machine problems, and inventory control -- with mean and 99th percentile of waiting times were examined by the hierarchical stepwise regression method. Day was a unit of the analyses. Results: The regression models explained 65.8% of variance in the mean waiting time and 61.34% in the 99th percentile of waiting times. The break-down of the printer for drug envelops, Automatic Tablet Counters (ATCs), and main computer system lasted longer than 30 minutes increased the mean for 7.7 minutes, 4.5 minutes, and 7.0 minutes, respectively, and the 99th percentile for 14.8 minutes, 9.0 minutes, and 15.7 minutes, respectively. Concerning the work force, study results showed that there were significant differences in the productivity of pharmacists with work experience more than three years, one to three years, and less than one year, and showed that peak time aid work by pharmacists at job assignments other than the outpatient pharmacy, part-time pharmacists, and the installation of ATCs were effective in reducing waiting times, Finally, study findings indicated that the operational policy of work assignment and rotation schedule, supply and inventory of drugs at work tables, and readiness for undisrupted work during the work hours could have a significant effect on waiting times. Conclusion: The study results indicated that efforts to reduce waiting times for prescribed drugs should be geared toward every components of the pharmacy work system ranging from work schedule of pharmacists and supply of dugs at work tables. These findings should provide hospital managers with right directions in battling the problem.

• Journal of Korean Biological Nursing Science
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• v.11 no.1
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• pp.32-41
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• 2009

Purpose: This study was to identify the effects of aroma inhalation therapy on heart rate variability and anxiety in the context of urodynamics study. Method: The data were collected from 64 patients who were receiving urodynamics at the C University Medical Center in Seoul, 23 in the experimental group, 22 in the placebo group and 19 in the control group. In the experiment, the subjects of the experimental group inhaled a mixture of lavender and bergamot for 5 min, the subjects of the placebo group inhaled geranyl acetate oil for 5 min and the subjects of the control group relaxed for 5 min. The instruments used in this study included the state anxiety inventory and heart rate variability. Result: The score of state anxiety was no significant differences between the three groups after aroma-inhalation. Also, the sympathetic nerve activity and parasympathetic nerve activity was no significant differences between the three groups after aroma-inhalation. Autonomic nerve balance was maintained significantly in the experimental group as compared to the control groups after aroma-inhalation. Conclusion: The aroma inhalation therapy was very effective in balancing the autonomic nervous system in the patients undergoing urodynamic study.

• Journal of Korean Library and Information Science Society
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• v.11
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• pp.143-173
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• 1984

This study has been done to review the historical development of the cataloging system of books with emphasis on those in England and the U. S. The findings can be summarized as follows: (1) In 1844, Sir Panizzi invented what seems to be the first of its kind in history to list the inventory systematically at the British Museum. It is believed to be a complete system consisting of 91 articles. (2) A comparatively systematic system was developed in America by Jewett. in 1852. Composed of only 39 articles, the system is considered a renovative one worked out with due regard to the infrastructure of a library. (3) In 1876, a classic system based on a lexicographical order was set up by Cutter. Rated as the best one that was designed by an individual, the theory has since exercised widespreading effects on cataloging. (4) American and British library scientists collaborated in printing several editions of numerous volumes on the principles of classification, but they are not believed fully successful in establishing a consistent and compressive system. Their efforts found significance rather in their being the first international collaboration and setting a foundation upon which the international system of today has been developed. (5) The ALA Rule, published concurrently in ALA and LC in 1949, had two parts in its classification, the list of authors and that of titles. Its scientific classification has completed the cataloging of books in its developmental stage. (6) The 1967 American-British Rules integrated the cataloging systems published under separate covers by authors and titles. The system as well as the 1961 Paris System has greatly contributed to the standardization of bibliographical description throughout the English-speaking countries. The International Standard Book Description standardized Bibliographic system has enabled the librarians in different countries to exchange their bibliographical sources easily, helped to overcome the language barrier in listing and contributed to the efficient reading of bibliographical records through machines. (7) The second edition of the Angelo-American cataloging Rules, promulgated in 1978 under the influence of the international standard bibliographical description, was the one in which all the previous Rules were revised to have their strong points. The adoption of punctuation system to employ the computerized data processing and the standardization of description are expected to improve the cataloging system not only in the English speaking countries but in the Universal Bibliographic Control as well.

• Journal of Biomedical Engineering Research
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• v.24 no.5
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• pp.427-434
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• 2003

In this paper, we present a speech-based Environmental Control System(ECS) and its application. In the concrete, an ECS using the speech recognition and an portable wheelchair lift control system with the speech synthesis are developed through the simulation and the embodiment. The developed system apply to quadriplegic man and we evaluate the result of physical effect and of mental effect. Speech recognition system is constructed by real time modules using HMM model. For the clinical application of the device, we investigate the result applied to 54-years old quadriplegic man during a week through the questionnaires of Beck Depression Inventory and of Activity Pattern Indicator. Also the motor drive control system of potable wheelchair lift is implemented and the mechanical durability is tested by structural analysis. Speech recognition rate results in over 95% through the experiment. The result of the questionnaires shows higher satisfaction and lower nursing loads. In addition, the depression tendency of the subject were decreased. The potable wheelchair lift shows good fatigue life-cycle as the material supporting the upper wheelchair and shows the centroid mobility of safety. In this paper we present an example of ECS which consists of real-time speech recognition system and potable wheelchair lift. Also the experiments shows needs of the ECS for korean environments. This study will be the base of a commercial use.

• Journal of Distribution Science
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• v.18 no.1
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• pp.85-94
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• 2020

Purpose: This study investigates the influence of VMI on the supply chain performance over time. By examining each supply chain member's ongoing performance, this study figures out how VMI allows the vendor to overcome the initial loss and eventually provides the benefit to every supply chain member. Research design, data, and methodology: The proposed mathematical model describes the supply chain system where a manufacturer and a retailer make the operational decisions to maximize their own profits. By using the numerical examples with arbitrary data, VMI and non-VMI are compared in terms of their profit changes over time. Results: The numerical analysis shows that VMI results in greater overall profits for both manufacturer and retailer than non-VMI, while the manufacturer make a loss in the early stage of VMI implementation. This study also examines the impacts of certain conditional factors on the performance of VMI. Conclusions: This study supports the idea that VMI leads to manufacturer's initial loss but it brings greater profits to both manufacturer and retailer than non-VMI after all. In addition, the result of this study provides the managerial implications about the particular condition that allows VMI to achieve a significant financial performance improvement over non-VMI.

• Proceedings of the KSR Conference
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• 2007.05a
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• pp.1244-1249
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• 2007

Pursuing sustainable development throughout society and industry and the field of environmental policy, each international organization or nation has performed international standardization projects on environmental management activities for their system as well as environmental assessment for a product such as life cycle assessment (LCA) and life cycle inventory database (LCI DB), and the environmental aspects have been increasingly demanded as crucial evaluation specifications. Moreover, the conventional environmental policy, which represents the direct-control, has been more dependent on the market forces and product itself after the Climate Change Convention., and the Integrated Product Policy (IPP, EU) is applied vigorously to strengthen global competitiveness of a product and to achieve the effect of environmental improvement for it. According to change of the international railway market, the value of Eco-Design has been increasingly important in developed countries including EU. Thus, each country is establishing its own guidelines, software and database for each product, and developing new policies through Eco-Design with practical results in marketing. To react this and develop Korean railway as an environment-friendly industry with priority to other transportation system as well as maintain high place in technology, the direction of RACE software development of main function is introduced, which is exclusively used for EMU to assess both environmental and economic aspects with LCA and eco-efficiency (EE).