• 한국시뮬레이션학회:학술대회논문집
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• 한국시뮬레이션학회 2003년도 추계학술대회 및 정기총회
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• pp.185-192
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• 2003

Digital Manufacturing-based production could be very effective in shipbuilding in order to save costs and time, to increase safety for workers, and to prevent bottleneck processes in advance. Digital shipbuilding system, a simulation-based production tool, is being developed to achieve such aspects in Korea. To simulate material flow in a subassembly line at a shipyard, the product, process and resources was modeled for the subassembly process which consisted of several sub-processes such as tack welding, piece alignment, tack welding, and robot welding processes. The analysis and modeling were carried out by using the UML(Unified Modeling Language), an object-oriented modeling method as well as IDEF(Integration DEFinition), a functional modeling tool. Initially, the characteristics of the shop resources were analyzed using the shipyard data, and the layout of the subassembly line was designed with the resources. The production process modeling of the subassembly lines was performed using the discrete event simulation method. Using the constructed resource and process model, the productivity and efficiency of the line were investigated. The number of workers and the variations In the resource performance such as that of a new welding robot were examined to simulate the changes in productivity. The bottleneck process floated according to the performance of the new resources. The proposed model was viewed three-dimensionally in a digital environment so that interferences among objects and space allocations for the resources could be easily investigated

• 생태와환경
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• 제55권4호
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• pp.341-351
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• 2022

The physiological characteristics, growth, and yield of each regional rice variety ('Odaebyeo', 'Saechucheong', 'Ilmibyeo') were investigated depending on the impact of changes in temperature and CO₂ concentration. Experiments were conducted with a control group, which reflected atmospheric CO₂ concentration and temperature, and treatment groups, in which the CO₂ concentration and temperature were increased by 250 ppm and 2.0℃ from those in the control group. The results showed that the increase in CO₂ concentration and temperature reduced the growth and yield of the rice 'Odaebyeo', but did not substantially change the productivity of the 'Saechucheong' and 'Ilmibyeo'. The increase in CO₂ concentration and temperature increased stomatal conductance and rate of transpiration of the 'Odaebyeo' variety, thereby decreasing its water use efficiency (WUE). In contrast, the increase in CO₂ concentration and temperature increased the photosynthetic rate and WUE of the 'Saechucheong' and 'Ilmibyeo' varieties. The gradual change in climate is considered to directly affect growth and development of rice and diversely affect the productivity of each variety. Therefore, it is necessary to implement technological development, select regionally optimal rice varieties, develop new rice varieties, as well as conduct long-term monitoring of each rice variety for climate adaptation to counter global warming.

• Fisheries and Aquatic Sciences
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• 제26권4호
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• pp.294-303
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• 2023

Beside that the fish species and their sub-populations are highly important as a keystone species in the coastal and marine ecosystem, there are very few studies on their presence, distribution and temporal variations within and around the lagoon ecosystems in Albania. This paper provides an updated review on the life cycle, fishery, exploitation state and management of the main species that are subject of commercial fishing in the Karavasta lagoon, southeastern Adriatic coast of Albania. Due to the fact that lagoons represent a continuum between continental and marine aquatic ecosystems they play a crucial role in species life cycles. Further on in the circumstances of rapid utilizations and environmental changes, anomalies in salinity and temperatures, accelerated anthropogenic influences their rate of vulnerability is highly increased. Following the requirements of the Water Framework Directive, transitional water, coastal lagoons and estuaries there is a need for urgent monitoring and management approaches. The commercial species include: European eel (Anguilla anguilla), species of Family Mugilidae (Mugil cephalus, Liza ramada, Liza salienes and Chelon labrosus), Seabream (Sparus aurata), Seabass (Dincentrarchus labrax), etc. Fish productivity is oscillating from maximum value of 61.95 kg/ha is recorded in period of 1975-80 and lower value of 31 kg/ha in year 2020. Our study highlights importance of fish and fishery long-term monitoring, and contributes to understand the driving factors in productivity, migration patterns and species ecology in the vital coastal ecosystems.

• 한국IT서비스학회지
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• 제23권1호
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• pp.27-35
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• 2024

In accordance with the cloud conversion of public sector information systems and the implementation of cloud native introduction policies, review items were presented to review the cloud native of information systems for stable and efficient cloud native deployment. By presenting cloud native considerations when promoting a project, we propose a plan to flexibly respond to policy and business changes and improve development quality and productivity to operate cloud services stably. In order for information project managers to switch to a cloud-native-based information system in order to efficiently utilize the cloud as a cloud, they must decide whether to introduce cloud-native through suitability review questions and sufficiently review development and operation costs and efficiency to promote the project. As a result of conducting a focus group interview (FGI) with a council of cloud native experts, there was an opinion that information systems can be operated in a cloud-native manner even with a monolithic structure. By fully considering the circumstances of each system, development quality and productivity, we expect to be able to operate improved to provide a stable cloud service.

• 한국의료질향상학회지
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• 제7권2호
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• pp.244-261
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• 2000

Background : In order to cope with changes in the management environment at hospitals, increased interests are drawn in patient foodservice system on Continuous Quality Improvement Activity as the method of approaching a quality food service and effective management. Thus, as a part of this activity, this study was conducted to evaluate job flow improvement that was already performed and the results of that process at the dietetic department of a university hospital, focusing on improving management. Method : On February 15 of 1998. the dietetic department formed a job flow-improvement to decide on the priority of job flow improvement, and prepared specific action strategies and schedule of the priority: after a 5 month process period, job improvement achieved on June 15. 1998. Also, economic achievement of the task was evaluated through labor productivity analysis and cost-benefit analysis. Results : The patient food service system which was managed decentralized at the present hospital was centralized, some steps of the food service process were integrated, and quality of patient food was improved. Also, as a solution of the problems expected when conducting job flow improvement was made on food service equipments and utensils. The result of evaluating the job flow improvement that labor productivity improved by 18.2% compared to before the improvement and the result of the analysis of cost-benefit showed that Benefit-Cost (B/C) ratio was 2.22. showing financial merit on the investment. Conclusions : Continuous Quality Improvement Activity needs to be initiated and conducted in the future in various areas of hospital foodservice system in order to actively adopt to ever changing hospital management environment. In order to achieve this goal, many researches and more efforts need to be put in by people in charge of hospital food service management, and interests and support are needed from hospital policy makers.

• 한국항해항만학회지
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• 제30권6호
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• pp.499-508
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• 2006

부산신항만의 개장과 함께 상하이항의 급속한 성장과 센젠항의 서비스와 생산성 신장뿐만 아니라 더욱 활동적인 광양항 등 한국의 항만은 국내외적으로 많은 변화에 직면하고 있다. 새로운 항만에 비교해서 부산항의 컨테이너 터미널들은 오래된 장비와 시설물을 보유하고 있으므로 서비스 수준과 경쟁력을 유지하기 위해 생산성 향상을 위한 리모델링에 착수할 필요성이 있다. 리모델링 활동은 게이트, 안벽, 야드, IT시스템 등에 대한 새로운 기술의 개발과 적용에 의해 지속적으로 시도되어야 한다. 영역별 대안들에 대한 기술적 검토를 위하여 설문조사와 면담조사를 하였으며, 리모델링 우선순위, 기술적용 기간, 적용 방향 등을 통해서 컨테이너터미널의 리모델링 활용계획을 설정하였다.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• 제3권3호
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• pp.189-196
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• 1999

The community structure, phytomass, and primary productivity in Thuja orientalis stands on a limestone area located in Maepo-up, Chungbuk province in Korea were estimated quantitatively. Seven species including a small proportion of Quercus dentata were identified in the tree layer, 26 species including Ulmus macrocarpa in the shrub layer, and 79 species including Carex lnceolata in the herb layer of the Thuja stands. The vertical distribution of the fine root phytomass exhibited a power functional decrease relative to the soil depth. The seasonal changes in the fine root phytomass at a soil depth of 5 cm were closely related to the pecipitation in the study area. The productivity of the stand of stems, branches, leaves, and roots were 10.72, 0.82, 0.45 and 6.46 ton DM. $ha^{-1}$ .$yr^{-1}$, respectively. The Thuja stand had a high foliage(25%) and low rate of production per unit of foliage. The annual turnover rate of the fine roots int he Thuja stand was 6.71 $yr^{-1}$. The net primary production of the overstory including the understory was estimated at 19.48 ton DM.$ha^{-1}$.$yr^{-1}$ including an underground section of 6.46 ton DM.$ha^{-1}$.$yr^{-1}$(33%). The allocation ratio of net production to root was lower in the limestone Thuja communities than at the nearby non-limestone ones, whereas the production efficiency to leaf weight was higher in the limestone communities. These results would seem to indicate that the limited production capacity is due to the calcium toxicity and low availability of iron and phosphorus in a limestone soil with a high pH, calcium, and bicarbonate content with a strategy for survival in a hostile habitat.

• 보건행정학회지
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• 제9권2호
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• pp.21-39
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• 1999

An increasing number of hospitals are seeking for new or mixed compensation strategies to improve the productivity of their medical staff in the struggle to provide high quality medical services at low costs amid the economic hardship. To motivate physicians toward the right direction, it is necessary to effectively evaluate their performance that provides a basis for compensation. However, productivity has been historically difficult to measure, particularly for physicians in academic medical centers who are expected to engage in research, education, and patient care simultaneously. The objectives of this study were to define performance measures of physicians and clinical departments in academic medical centers. to examine correlations between the measures. and to investigate factors affecting the measures. The performance data of 212 faculty physicians in 17 clinical departments in two university teaching hospitals affiliated to one medical school during the fiscal year 1994 was used for analyses. Patient care revenue, net profit. and adjusted number of patients were defined to measure the performance in patient care. and number of articles published in academic journals and research grant were defined for research activities. Both individual physicians' performance measures and per physician measures of clinical departments were analyzed. All measures defined to evaluate individual physicians' performance were positively related to each other. Clinical department and rank of faculty position were statistically significant predictors of revenue. and hospital. clinical department. and rank were significant predictors of net profit. journal publication. and research grant. Patient care measures defined to evaluate clinical departments were related to each other. so were research measures. and no significant correlations were found between patient care measures and research measures. Also found were large differences in department. ranks when clinical departments were evaluated by absolute per physician performance measures and evaluated by annual rate of changes in performance measures. These findings suggest that departmental performance measures opposed to individual performance measures are relatively free from problems of factors affecting the performance measures that are not in control of clinical departments or individual physicians. Results from the correlation analysis of departmental performance measures indicates that measures of research performance should be included in the evaluation to promote research activities in academic medical centers.

• Ocean and Polar Research
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• 제34권2호
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• pp.239-251
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• 2012

The food web dynamics in a coastal ecosystem of Korea were predicted with Ecosim, a trophic flow model, under various scenarios of primary productivity due to ocean warming and ocean acidification. Changes in primary productivity were obtained from an earth system model 2.1 under A1B scenario of IPCC $CO_2$ emission and replaced for forcing functions on the phytoplankton group during the period between 2020 and 2100. Impacts of ocean acidification on species were represented in the model for gastropoda, bivalvia, echinodermata, crustacean and cephalopoda groups with effect sizes of conservative, medium and large. The model results show that the total biomass of invertebrate and fish groups decreases 5%, 11~28% and 14~27%, respectively, depending on primary productivity, ocean acidification and combined effects. In particular, the blenny group shows zero biomass at 2080. The zooplankton group shows a sudden increase at the same time, and finally reaches twice the baseline at 2100. On the other hand, the ecosystem attributes of the mean trophic level of the ecosystem, Shannon's H and Kempton's Q indexes show a similar reduction pattern to biomass change, indicating that total biomass, biodiversity and evenness shrink dynamically by impacts of climate change. It is expected from the model results that, after obtaining more information on climate change impacts on the species level, this study will be helpful for further investigation of the food web dynamics in the open seas around Korea.

• 공업화학
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• 제18권6호
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• pp.531-536
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• 2007

본 총설은 최근 제지 분야에 적용되어 종이의 품질을 향상시키고 생산효율을 개선하는 등 제지산업의 경제성 향상을 이끌어 내거나 장차 이끌어낼 것으로 기대되는 새로운 제지용 첨가제를 소개하기 위하여 작성되었다. 본 총설에서는 최근 개발되어 제지 현장에 적용된 새로운 첨가제에 대한 소개뿐만 아니라 그 적용 원리, 방법, 조절 및 점검 방안과 향후 발전 방향에 대하여 논의하였다. 기본적으로 2000년대에 들어선 지난 수년 동안 제지산업의 기술개발 노력은 기 개발된 기술의 최적화를 통한 경제성 확보 및 종이 품질과 생산 효율의 개선에 집중되어 왔다. 따라서 제지용 첨가제 분야에 혁신적인 변화는 없었다고 볼 수 있으나 기술적인 측면에서 몇 가지 중요한 첨가제의 개발이 보고되었으며 이를 바탕으로 기존의 제지공정에 대한 보다 합리적인 관리가 가능하게 되었다고 할 수 있다.