• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.1
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• pp.86-92
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• 2009

This paper presents development of 6kw ZVS(Zero Voltage Switching) boost converter by 4-parallel operation. To realize a high capacity converter with 6 kw, 4-parallel operation of 1.5kW unit module is proposed in this paper. To meet high ratio input to output voltage, isolated type booster converter is designed. To achieve ZVS operation of 4-switches of full bridge and protect a voltage overshoot caused by switch turn-off, simple active-clamp circuit is applied to the primary side. For parallel operation of 4-modules, master-slave control method is proposed to achieve input current sharing of 4-unit converter modules accurately. For performance tests, simulation is carried out. Also, load and experimental tests of the developed booster converter, 230Vdc/6kW, are carried out under various conditions. For field tests, the developed converter is applied for boosting a battery power to high DC_link voltage for a VSI inverter which starts a micro-turbine(MT) installed in vehicle and it's performance is verified through high speed motoring a MT up to tens of thousands of rpm.

• Journal of Korean Society of Rural Planning
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• v.19 no.4
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• pp.227-235
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• 2013

As policy for regional development in bottom-up style is introduced, each local government reflects opinion of regional residents and experts, and continues to strive for active use of regional capability and natural resources. As a result, there are active movements for regional development in Eup and Myeon unit or village unit inside local government. Comprehensive arrangement project in areas of Eup and Myeon is proceeded with a goal of improvement of life quality for regional residents through strengthening base function of Eup and Myeon areas and improving function of basic service by expanding facility of optimal level available to an unspecified number of the general public such as educational, cultural, welfare facility etc. in Eup and Myeon areas which are base space of rural communities. For analysis method of region for selecting areas where comprehensive arrangement project is done, this study suggested analysis of connection structure based on interaction and analysis of centrality. And empirical analysis was carried out with Buyeo province in Chungcheongnamdo.

• Journal of Institute of Control, Robotics and Systems
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• v.12 no.11
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• pp.1074-1080
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• 2006

Motion capture systems are gaining popularity in entertainment, medicine, sports, education, and industry, with animation and gaming applications for entertainment taking the lead. A wide variety of systems are available for motion capture, but most of them are complicated and expensive. In the general class of optical motion capture, two or more optical sensors are needed to measure the 3D positions of the markers attached to the body. Recently, a 3D motion capture system using two Position Sensitive Detector (PSD) optical sensors was introduced to capture high-speed motion of an active infrared LED marker. The PSD-based system, however, is limited by a geometric calibration procedure for two PSD sensor modules that is too difficult for common customers. In this research, we have introduced a new system that used a single PSD sensor unit to obtain 3D positions of active IR LED-based markers. This new system is easy to calibrate and inexpensive.

• Journal of the Korea Safety Management & Science
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• v.23 no.4
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• pp.121-133
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• 2021

The composition of human resources in industrial sites is becoming global. In Korea, too, the proportion of foreign members in all industrial fields and production sites is increasing. This is the reason why an approach that reflects this reality is needed in the basic unit of competitive sources. Competitiveness starts with value creation, and this progresses through field innovation. Through empirical analysis of this study, it was analyzed that South Korea members showed active actions and attitudes in developing, promoting, and realizing ideas when they strongly recognized the real meaning of empowerment given by leaders. On the other hand, it was found that foreign members do not know the meaning of empowerment itself, so they are often unable to play an active role in the development, promotion, and realization of ideas. In fact, it was analyzed that foreign members generally did not experience positive interactions with LMX and were exposed to simple tasks and controls. In other words, they are being discriminated against in terms of communication problems, compensation system, and work environment. In particular, this phenomenon is exacerbated in the case of small and medium-sized enterprises (SMEs). Situational response to foreign workers through improvement of LMX and empowerment should be evaluated as a key management task in a situation where productivity improvement and job unit innovation are urgently needed.

• Korean Journal of Clinical Pharmacy
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• v.25 no.3
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• pp.138-144
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• 2015

Objective: It is to evaluate the drug interaction monitoring program as a pilot project to develop a pharmaceutical care model in a medical intensive care unit and to analyze the influencing factors of drug interactions. Method: Electronic medical records were retrospectively investigated for 116 patients who had been hospitalized in a medical intensive care unit from October to December in 2014. The prevalence of adverse reaction with risk rating higher than 'D' was investigated by Lexi-$Comp^{(R)}$ Online database. The factors related with potential drug interaction and with treatment outcomes were analyzed. Results: The number of patients with a potential interaction of drug combination was 92 (79.3%). Average ages, the length of stay in the intensive care unit and the numbers of prescription drugs showed significant differences between drug interaction group and non-drug interaction group. Opioids (14.4%), antibiotics (7.2%), and diuretics (7.2%) were most responsible drug classes for drug interactions and the individual medications included furosemide (6.4%), tramadol (4.9%), and remifentanil (4.5%). There were 950 cases with a risk rating of 'C' (84.6%), 142 cases with a risk rating of 'D' (12.6%), and 31 cases with a risk rating of 'X' (avoid combination) (2.8%). The factors affecting drug interactions were the number of drugs prescribed (p < 0.0001) and the length of stay at intensive care unit (p < 0.01). The patients in intensive care unit showed a high incidence of adverse reactions related to potential drug interaction. Therefore, drug interaction monitoring program as a one of pharmaceutical care services was successfully piloted and it showed to prevent adverse reaction and to improve therapeutic outcomes. Conclusion: Active participation of a pharmacist in the drug management at the intensive care unit should be considered.

• Structural Engineering and Mechanics
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• v.61 no.3
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• pp.347-357
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• 2017

The applications of active control is being more popular nowadays. Several control algorithms have been developed to determine optimum control force. In this paper, a Chaotic Particle Swarm Optimization (CPSO) technique, based on Logistic map, is used to compute the optimum control force of active tendon system. A chaotic exploration is used to search the solution space for optimum control force. The response control of Multi-Degree of Freedom (MDOF) shear buildings, equipped with active tendons, is introduced as an optimization problem, based on Instantaneous Optimal Active Control algorithm. Three MDOFs are simulated in this paper. Two examples out of three, which have been previously controlled using Lattice type Probabilistic Neural Network (LPNN) and Block Pulse Functions (BPFs), are taken from prior works in order to compare the efficiency of the current method. In the present study, a maximum allowable value of control force is added to the original problem. Later, a twenty-story shear building, as the third and more realistic example, is considered and controlled. Besides, the required Central Processing Unit (CPU) time of CPSO control algorithm is investigated. Although the CPU time of LPNN and BPFs methods of prior works is not available, the results show that a full state measurement is necessary, especially when there are more than three control devices. The results show that CPSO algorithm has a good performance, especially in the presence of the cut-off limit of tendon force; therefore, can widely be used in the field of optimum active control of actual buildings.

• The Transactions of the Korea Information Processing Society
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• v.2 no.6
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• pp.985-994
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• 1995

In this paper, we propose two hot standby architectures which not only provide high system availability but also lose little data on fault occurrence. In order to evaluate the performance of the proposed hot standby architectures, the warm standby architecture. In order to evaluate the performance of the propose d hot standby architectures, the warm standby architecture which is made from the hot standby architecture by eliminating its synchronization unit is considered. After system unavailability for each architecture is computed by using the corresponding Markov state diagram, the results are compared and evaluated. As the results, in most cases, hot standby architectures have higher availability than warm standby architecture. Also, hot standby architecture with external synchronization unit always maintains a little higher availability than hot standby architecture with internal synchronization unit. Active set time and personnel recovery rate for each architecture have little effect on system availability. However, in the case that data recovery time is too long, system availabilities of hot standby architectures and warm standby architecture degrade rapidly. In this case, the performance degradation of hot standby architectures is severe, and system availabilities of hot standby architectures eventually become lower than system availability of warm standby architecture.

• Journal of Life Science
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• v.25 no.2
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• pp.130-135
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• 2015

When the alginate lyase gene (aly) from Pseudoalteromonas elyakovii IAM 14594 was expressed in E. coli, most of the gene product expressed was produced as aggregated insoluble particles known as inclusion bodies. In order to produce with an elevated level of a soluble and active form of alginate lyase in E. coli, the hyperthermophilic chaperonins (ApCpnA and ApCpnB) from archaeon Aeropyrum pernix K1 were employed as the coexpression partners. At $25^{\circ}C$ culture temperature, the level of alginate lyase activity was increased from 10.1 unit/g-soluble protein in aly single expression to 83.1 unit/g-soluble protein by coexpressing with ApCpnA and to 100.3 unit/g-soluble protein by coexpressing with ApCpnB. This results indicate that the coexpression of aly with ApCpnA and ApCpnB revealed a marked enhancement, about 8~10 fold, in the production of alginate lyase as a soluble and active form. Based on the results of various examinations on the expression variables, the optimal conditions for the maximal production of alginate lyase were determined as 1.0 mM IPTG for the inducer concentration, $25^{\circ}C$ for the culture temperature after IPTG induction, and ApCpnB for the coexpression partner. The coexpression set in the present report may be useful in the industrial production of functionally or medically important recombinant proteins in E. coli.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.3
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• pp.450-457
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• 2011

Roasted soybean flour (RSF) and mixed cereals were fermented by the solid state fermentation using Bacillus subtilis HA to optimize the production of biologically active compounds. The RFS fermented with 52.7% moisture content showed higher production with protease activity of 42.6 unit/g and 10% mucilage content after fermentation for 24 hr. Tyrosine content and protease activity after 48 hr fermentation time were the highest values with 445.5 mg% and 55.1 unit/g, respectively. However, the wholesome fermented RSF (FRSF) was obtained by fermentation for 24 hr because of the production of unpleasant flavors after fermentation for 48 hr. The RSF fermented with various types and contents of cereals has no effects on tyrosine content and protease activity. However, the addition of brown rice significantly increased mucilage content, especially indicating 24.55% at the addition of 80% (w/w). For addition of barley, fibrinolytic activity was increased to 11.82 unit/g by the fortification of 60% barley. It is concluded that biologically active compounds including fibrinolytic activity and mucilage content in FRSF were dependent upon the type and content of various cereals.

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.1937-1941
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• 2007

During a process of a nanoimprint for manufacturing LCD, a small temperature variation on the LCD glass can cause thermal stress and generate unexpected displacement. To avoid this trouble, a precision temperature control unit using thermoelectric modules is appropriate for nanoimprint processes. The unit consists of an air control system, a cooling water control system, and a power control system. The air control system includes a thermoelectric module, thermocouples measuring temperatures of air and a duct-stale fin, and two air fans. The heat generated by the thermoelectric module is absorbed by the cooling water control system. The power control system catches the temperature of the thermoelectric module, and a PID controller with SCR controls the input power of the thermoelectric module. Temperature control performance is evaluated by experiment and simulation. The temperature control unit is able to control the exit temperature about ${\pm}2^{\circ}C$ from the incoming fluid temperature, and the error range is ${\pm}0.1^{\circ}C$. However, the control time is approximately 30minute, which needs further study of active control