• Proceedings of the Korea Database Society Conference
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• 1999.06a
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• pp.75-84
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• 1999

본 논문에서는 지식에 대한 개념을 정의하기 보다 지식의 life-cycle을 통한 지식의 생성과 소멸을 모델화함으로 지식을 설명하려 한다. 본 논문은 노나카의 지식 창조 모델을 기반으로 하고 기존의 KMS들을 분석하여 일반적인 지식 life-cycle 모델을 도출하였으며, 기존 모델의 문제점을 보완하여 새로운 지식 life-cycle 모델을 만들었다. 이 모델과 앞으로의 지식관리 시스템 발전 방향을 고려하여 지식 관리 시스템 아키텍쳐를 제시하였다. 본 논문에서는 이 아키텍쳐를 근거로 지식 관리 시스템을 구현하기 위한 6개의 컴포넌트를 도출하였다 6개의 컴포넌트는 지식 생성, 지식 분배, 지식 측정, 지식연결, 지식 검색, 지식 저장이다. 이 컴포넌트들로 지식 관리 시스템의 prototype을 구현해 본 결과 지식life-cycle을 단계적, 부분적으로 지원하지만 부족한 부분이 있는 것을 발견하였다. 향후에는 지식 생성과 지식 연결 컴포넌트를 강화하여 전체적인 지식 life-cycle을 지원할 예정이다.

• BMB Reports
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• v.36 no.1
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• pp.60-65
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• 2003

Cancer is frequently considered to be a disease of the cell cycle. As such, it is not surprising that the deregulation of the cell cycle is one of the most frequent alterations during tumor development. Cell cycle progression is a highly-ordered and tightly-regulated process that involves multiple checkpoints that assess extracellular growth signals, cell size, and DNA integrity. Cyclin-dependent kinases (CDKs) and their cyclin partners are positive regulators of accelerators that induce cell cycle progression; whereas, cyclin-dependent kinase inhibitors (CKIs) that act as brakes to stop cell cycle progression in response to regulatory signals are important negative regulators. Cancer originates from the abnormal expression of activation of positive regulators and functional suppression of negative regulators. Therefore, understanding the molecular mechanisms of the deregulation of cell cycle progression in cancer can provide important insights into how normal cells become tumorigenic, as well as how cancer treatment strategies can be designed.

• Proceedings of the Korea Inteligent Information System Society Conference
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• 1999.03a
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• pp.75-84
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• 1999

본 논문에서는 지식에 대한 개념을 정의하기 보다 지식의 life-cycle을 통한 지식의 생성과 소멸을 모델화함으로 시식을 설명하려 한다. 본 논문은 노나카의 지식 창조 모델을 기반으로 하고 기존의 KMS들을 분석하여 일반적인 지식 life-cycle 모델을 도출하였으며, 기존 모델의 문제점을 보완하여 새로운 지식 life-cycle 모델을 만들었다. 이 모델과 앞으로의 지식관리 시스템 발전 방향을 고려하여 지식 관리 시스템 아키텍쳐를 제시하였다. 본 논문에서는 이 아키텍쳐를 근거로 지식 관리 시스템을 구현하기 위한 6개의 컴포넌트를 도출하였다. 6개의 컴포넌트는 지식 생성, 지식 분배, 지식 측정, 지식 연결, 지식 검색, 지식 저장이다. 이 컴포넌트들로 지식 관리 시스템의 prototype을 구현해 본 결과 지식 life-cycle을 단계적, 부분적으로 지원하지만 부족한 부분이 있는 것을 발견하였다. 향후에는 지식 생성과 지식 연결 컴포넌트를 강화하여 전체적인 지식 life-cycle을 지원할 예정이다.

• The Journal of Korean Obstetrics and Gynecology
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• v.24 no.3
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• pp.73-84
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• 2011

Objectives: This study examined the recent update of factors affect length and regularity of menstrual cycle and symptoms need for diagnosis in oriental medicine. Methods: For factors, we searched the key word "menstrual cycle length and factor" in ScienceDirect(http://www.sciencedirect.com) and we mainly searched symptoms in the journal of oriental obstetrics & gynecology and text. Results: The result are shown in the Table 1-3. Conclusion: In fact as the fluctuation of menstrual cycle length and regularity is very high in healthy women, we must observe the factor affect menstrual cycle with attention even though rule out disease, operation and HRT etc. these researches show potential to compound oriental medicine care and factor of menstrual cycle change.

• Journal of Mechanical Science and Technology
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• v.14 no.10
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• pp.1151-1158
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• 2000

Combustion analysis based on cylinder-pressure provides a mechanism through which a combustion researcher can understand the combustion process. The objective of this paper was to identify the most significant sources of cycle-to-cycle combustion variability in a spark ignition engine at idle. To analyse the cyclic variation in a test engine, the burn parameters are determined on a cycle-to-cycle basis through the analysis of the engine pressure data. The burn rate analysis program was used here and the burn parameters were used to determine the variations in the input parameter-i. e., fuel, air, and residual mass. In this study, we investigated the relationship of indicated mean effective pressure (IMEP), coefficient of variation (COV) of IMEP, burn angles, and lowest normalized value (LNV) in a spark ignition engine in a view of cyclic variations.

• International Journal of Automotive Technology
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• v.2 no.1
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• pp.25-31
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• 2001

It is necessary to understand the combustion process and cycle-by-cycle variation in combustion to improve the engine stability and consequently to improve the fuel economy and exhaust emissions. The pressure related parameters instead of mass fraction burned were compared for the effect of initial combustion pressures on the following combustion and the analysis of cycle-by-cycle variation in combustion for two pen injected SI engines. The correlation between IMEP and pressures at referenced crank angles showed almost the same trends for equivalence ratios, but the different mixture preparations indicated different tendency. The dependency of IMEP on pressure at the referenced crank angles increases as the mixture becomes leaner for both engines. The mixture distribution in the combustion chamber was varied with the coolant temperature and intake valve deactivation due to the evaporation of fuel and air motion. The correlation between pressure related parameters were also compared for the coolant temperatures and air motion.

• Progress in Superconductivity and Cryogenics
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• v.1 no.1
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• pp.48-55
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• 1999

thermodynamic cycle analysis has been performed for the power generation systems to utilize the cold energy of liquefied natural gas (LNG). The power cycle used the air or water at room temperature as a heat source and the LNG at cryogenic temperature as a heat sink. Among manypossible configurations of the cycle. the open Rankine cycle. and the closed Brayton cycle, and the closed Rankine cycle are selected for the basic analysis because of their practical importance. The power output per unit mass of LNG has been analytically calculated for various design parameters such as the pressure ratio. the mass flow rate. the adiabatic efficiency. the heat exchanger effectiveness. or the working fluid. The optimal conditions for the parameters are presented to maximize the power output and the design considerations are discussed. It is concluded that the open Rankine cycle is the most recormmendable both in thermodynamic efficency and in practice.

• Journal of Industrial Technology
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• v.23 no.A
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• pp.193-197
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• 2003

This bench-scale research investigated the aeration cycle(on/off) as the controlling factors for nitrogen and phosphorus removal in a 2-stage, intermittent aeration process. At this experiment, the aeration cycle time(air-on/air-off) was 30min/30min, 60min/60min, 90min/90min. Organic matter removal was observed more than 90% regardless of the aeration cycle and phosphorus removal was relatively high when the aeration cycle time was 60min/60min On the other hand. For all of the aeration cycle, TN removal was appeared less than 55%. This result was probably due to the limitation of the external substrate for heterotrophic nitrification and aerobic denitrification.

• Transactions of the Korean hydrogen and new energy society
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• v.29 no.5
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• pp.490-496
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• 2018

Recently, the power and refrigeration cogeneration based on Kalina cycle has attracted much attention for more efficient utilization of low-grade energy. This study presents a thermodynamic performance analysis of a cogeneration cycle of power and absorption refrigeration based on Kalina cycle. The cycle combines Kalina cycle (KCS-11) and absorption cycles by adding a condenser and an evaporator between turbine and absorber. The effects of ammonia mass fraction and separation pressure were investigated on the system performance of the system. Results showed that the energy utilization of the system could be greatly improved compared to the basic Kalina cycle.

• Proceedings of the KSME Conference
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• 2008.11b
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• pp.2971-2976
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• 2008

Recently, there has been growing interest in the oxyfuel combustion cycle since it enables high-purity CO2 capture with high efficiency. However, the oxyfuel combustion cycle has some important issues regarding to its performance such as the requirement of water recirculation to decrease a turbine inlet temperature and proper combustion pressure to enhance cycle efficiency. The purpose of the present study is to analyze performance characteristics of the oxyfuel combustion cycle with different turbine inlet temperatures and combustion pressures. It is expected that the turbine inlet temperature improves cycle efficiency, on the other hand, the combustion pressure has specific value to display highest cycle efficiency.