• 한국해양학회지
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• v.26 no.2
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• pp.108-116
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• 1991

A production model was constructed by combining the production rate and biomass of Sargassum confusum measured at monthly intervals on the coast of Ohori, Korea, to estimate the algal production for a given period. The production for a certain period, e.g., for a year (P/SUB yr/), was calculated from the equation: P/SUB yr/ = .int.P/SUB t/$.$B/SUB t/dt, where pl and Bl are the production rate and biomass at time t. P/SUB l/ was considered as a function of temperature and light. Photosynthesis-Irradiance curves obtained from the in situ experiments were applied for P/SUB l/ Temperature and light intensity can be expressed as periodic functions of time (T, L=f(t)). Diurnal values of water temperature and light intensity at 3 m depth where S. confusum mainly found were substituted into the equation of P/SUB l/. Simulations using our models show that temperature was one of the most sensitive factors operating on the primary production. Thirty percent decrease of light intensity by cloud cover was estimated to decrease the annual production by 5%.

• Journal of Bio-Environment Control
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• v.13 no.4
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• pp.209-216
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• 2004

This study was aimed to assess the effects of microclimate factors on lettuce chlorophyll fluorescent responses and to develop an environment control system for plant growth by adopting a simple genetic algorithm. The photosynthetic responses measurements were repeated by changing one factor among six climatic factors at a time. The maximum Fv'/Fm' resulted when the ambient temperature was $21^{\circ}C,\;CO_2$ concentration range of 1,200 to 1,400 ppm, relative humidity of $68\%$, air current speed of $1.4m{\cdot}s^{-1}$, and the temperature of nutrient solution of $20^{\circ}C$. In PPF greater than $140{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, Fv'/Fm' values were decreased. To estimate the effects of combined microclimate factors on plant growth, a photosynthesis efficiency model was developed using principle component analysis for six microclimate factors. Predicted Fv'/Fm' values showed a good agreement to measured ones with an average error of $2.5\%$. In this study, a simple genetic algorithm was applied to the photosynthesis efficiency model for optimal environmental condition for lettuce growth. Air emperature of $22^{\circ}C$, root zone temperature of $19^{\circ}C,\;CO_2$ concentration of 1,400 ppm, air current speed of $1.0m{\cdot}s^{-1}$, PPF of $430{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, and relative humidity of $65\%$ were obtained. It is feasible to control plant environment optimally in response to microclimate changes by using photosynthesis efficiency model combined with genetic algorithm.

• Microbiology and Biotechnology Letters
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• v.40 no.1
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• pp.10-16
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• 2012

The Streptomyces peucetius OIM (Overproducing Industrial Mutant) strain is a recursively-mutated and optimally-screened strain used for the industrial production of polyketide antibiotics, such as doxorubicin (DXR). Using the S. peucetius OIM mutant strain as a surrogate host, a model minimal polyketide pathway for aloesaponarin II, an actinorhodin shunt product, was cloned in a high-copy conjugative plasmid, followed by functional pathway expression and quantitative metabolite analysis. The level of aloesaponarin II production was noted as being significantly higher in the OIM strain than in the wild-type S. peucetius, as well as in the regulatory network-stimulated S. coelicolor mutant strain. Moreover, the aloesaponarin II production level was seen to be even higher in a down-regulator $wblA_{spe}$-deleted S. peucetius OIM strain, implying that the rationally-engineered S. peucetius OIM mutant strain could be used as an efficient surrogate host for the high expression of foreign polyketide pathways.

• Journal of the Korea Institute of Building Construction
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• v.23 no.3
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• pp.273-284
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• 2023

This study is centered on the combined use of LiDAR(Light Detection and Ranging) and AR(Augmented Reality) technologies during vertical and horizontal frame measurements in construction projects. The intention is to enhance the quality control procedure, elevate accuracy, and curtail manual labor along with time expenditure. Present methods for accuracy inspection in frame construction often grapple with reliability concerns due to subjective interpretation and the scope for human error. This research recommends the application of LiDAR and AR technologies to counter these issues and augment the efficiency of the inspection process, along with facilitating the dissemination of results. The suggested technique involves the collection of 3D point cloud data of the frame utilizing LiDAR and leveraging this data for checks on construction accuracy. Furthermore, the inspection outcomes are fed into a BIM (Building Information Modeling) model, and the results are visualized via AR. Upon juxtaposing this methodology with the current approach, it is evident that it offers benefits in terms of objective inspection, speed, precise result sharing, and potential enhancements to the overall quality and productivity of construction projects.

• Proceedings of the Korean Statistical Society Conference
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• 2003.10a
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• pp.289-294
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• 2003

최근 활발히 행하여지는 금융 CRM(Customer Relationship Management)은 은행의수익성 제고를 위하여 개별고객의 주요특성(거래이력, 가치 등)을 파악하고, 이를 근거로 유사한 고객들을 분류하여 고객관리 방안을 찾는데 그 목적이 있다. 본 연구에서는 B은행의 실제 CRM을 통하여 수익성을 높일 수 있는 마케팅 시사점을 도출하고자 하며 이러한 마케팅의 도출과 목표가 되는 고객을 어떻게 선정할 것인가의 질문에 대한 방법으로 계량경제학 분야에서 기업단위연구의 생산효율성을 측정하기 위하여 사용되어지고 있는 SFM(Stochastic Frontier Model)과 OLS(Ordinary Linear Model)의 방법을 사용하였다.

• Proceedings of the Korean Society of Computer Information Conference
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• 2022.07a
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• pp.107-109
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• 2022

본 논문은 건설구조물 안전의 가장 중요한 요소 중 하나인 콘크리트 압축강도 안정성을 확보하기 위한 시스템으로, 콘크리트 구조물을 만들 재료인 레미콘의 수분 감소율에 따른 압축강도 감소 리스크를 관리할 수 있는 모델을 제시하였다. 동일한 물,시멘트비(W/C)로 생산된 레미콘은 현장타설시까지 교통환경으로 인한 도착시간 지연 및 강우, 강설 등 외부적인 요건으로 감수율이 발생하는 리스크가 발생한다. 이로 인해 콘크리트의 압축강도가 저감하는 중대한 문제가 발생한다. 본 연구에서 제시한 알고리즘을 이용하여 현장 타설전 콘크리트 시료의 함수율을 측정하여 감수율이 발생한 제품 발견시, 실시간으로 Operator로 GCM 기반의 Push Alarm을 전송하여 감수율이 반영된 제품을 제공함으로써 구조물의 안전성을 확보할 수 있는 시스템을 모델링하였다. 본 연구는 기존시스템의 문제점을 실시간으로 개선할 수 있는 것으로 건설현장의 구조물 안정성 확보에 효과가 클 것으로 기대된다.

• Proceedings of the Korean DIstribution Association Conference
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• 2006.02a
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• pp.283-307
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• 2006

최근의 서비스 마케팅 문헌은 서비스 조직의 경쟁력 향상의 방편으로 서비스 고객에게 관심을 집중하고 있는 실정이다. 특히 서비스 고객은 부분적 종업원으로 인식될 수 있기 때문에 서비스 조직에 대해 참여행동을 나타낼 수 있으며, 이를 통해서 서비스 조직은 추가적 비용 없이 경쟁력을 향상시킬 수 있다. 이에 따라 고객행동 관리가 강조되고는 있으나 아직까지 실증적 연구의 주제로는 거의 다루어지고 있지 않다. 따라서 본 연구는 지금까지 간과되었던 부분인 고객참여가 고객만족에 어떻게 영향을 미치는지에 대한 메카니즘을 실증적으로 분석하기 위해, 고객참여의 영향을 매개하는 변수로서 서비스 성과와 기대를 제시하는 연구모델을 설정하였다. 구성개념을 측정하기 위해 관련 문헌들을 참고하였으며, 본 연구의 서비스 상황에 적합하도록 수정을 가하였다. 최근에 교육 서비스와 병원 서비스를 제공받은 경험이 있는 대학생을 대상으로 구조방정식을 사용하여 분석한 결과, 연구모델의 적합도는 양호하였으며 모든 연구가설이 지지되었다. 참여는 매개변수로 제시된 성과, 기대와 유의한 관계를 가지는 것으로 나타났으며, 성과와 기대는 또한 만족에 유의한 영향을 미치는 것으로 나타났다. 이러한 분석결과를 통해서 서비스 관리자는 종업원과 마찬가지로 서비스 고객을 적극적으로 관리할 필요성이 있고, 특히 고객의 서비스 성과지각과 서비스 기대에 더욱 관심을 기울여야 함을 이해할 수 있었다. 마지막으로, 이러한 실증결과에 대한 시사점을 논의하였고 미래연구를 위한 방향을 제시하였다.

• Journal of Acupuncture Research
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• v.24 no.2
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• pp.73-81
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• 2007

목적 : 본 연구는 화피의 연골 보호 및 소염 진통 작용을 알아보고, 화피를 이용한 관절염치료 약침액 개발의 기초자료를 얻기 위해 고안되었다. 방법 : In vitro에서는 토끼 무릎관절에서 배양된 연골조직에 5ng/ml IL-1${\alpha}$ 처리 후， 화피의 연골보호 효과, 연골세포에 대한 독성을 조사하였다. In vivo에서는 토끼 무릎관절내 collagenase를 주입, CIA 유발 후, 28일간 매일 토끼의 구강으로 화피, 증류수, CEX를 투여하였으며, 연골보호, 소염, 진통에 대한 측정을 하였다. 결과 : 화피는 proteoglican 및 collagen분해 억제, MMPs 활성 억제로 연골 보호 효과가 있었으며, 연골 세포에 대한 독성이 없었다. 소염작용은 PGE2 생산 억제 및 COX-2발현 억제, carrageenan 유발 쥐 모델에서의 부종 억제로 확인되었다. 진통작용은 tail flick test에서의 latency time 증가, formalin test에서의 염증성 통증억제로 나타났다. 결론 : 화피가 퇴행성관절염에 대한 연골 보호 효과 및 소염 진통 작용이 있으므로, 이를 근거로 약침액을 개발 응용하면 퇴행성관절염 치료에 활용될 수 있다고 사료된다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.3D
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• pp.363-369
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• 2008

Change is inevitable and is a reality of construction projects. Change adjustment includes the cost associated with materials, labor, etc. 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. What is needed is a reliable method to identify and quantify the loss of productivity caused by cumulative impact of change orders. This study survey the change orders data in domestic area for public construction and analyze to quantify change order impact. This study developed concepts of "%CO", "%Delta", "%T" to capture change order effect on project and search the relationships between them. Finally, this study find strong relationship between change order and loss.

• Korean Journal of Construction Engineering and Management
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• v.14 no.3
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• pp.134-145
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• 2013

Road construction projects are parcelled into sub-sections which are then tendered to individual contractors for construction. The type of work and equipments used are similar for each sub-section. However, such equipment are not shared on a regular basis among the contractors and only partially performed in an informal and ad hoc manner. Consequently, road construction equipment suffer from low utilization and increased leasing costs. Lean construction and Program Management approaches stress the importance of collaboration among individual participants in a way that increases the collective cost savings of the entire project. This research attempts to apply such theories with the notion that under utilization of expensive equipment can be improved by formalizing a way to enable the sharing of equipment in large, public sponsored, multi-sectioned road construction projects. A system was developed consisting of a set of criteria and processes that enables automatic allocation of equipment to multiple sites on daily basis, in a way that minimizes equipment costs and improves their individual utility. The system was then applied in allocating three different types of equipment to an actual road construction project with four sub-sections for three months. A new metric, nDPR showed that utilization improved for all equipment and also equipment related costs were decreased by 4.45%. Results also showed that increased shared opportunities of equipment correspond to an increase in utilization and cost savings.