• Journal of Power Electronics
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• 제16권1호
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• pp.340-350
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• 2016

A cascaded hybrid multilevel inverter including a reconfiguration technique for low voltage dc distribution applications is proposed in this paper. A PWM generation fault detection and reconfiguration paradigm after an inverter cell fault are developed by using only a single-chip controller. The proposed PWM technique is also modified to reduce switching losses. In addition, the proposed topology can reduce the number of required power switches compared to the conventional cascaded multilevel inverter. The proposed technique is validated by using a 3-kVA prototype. The switching losses of the proposed multilevel inverter are also investigated. The experimental results show that the proposed hybrid inverter can improve system efficiency, reliability and cost effectiveness. The efficiency of proposed system is 97.45% under the tested conditions. The proposed hybrid inverter topology is a promising method for low voltage dc distribution and can be applied for the multiple loads which are required in a data center or telecommunication building.

• 한국초전도ㆍ저온공학회논문지
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• 제21권3호
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• pp.47-50
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• 2019

The paper gives the results of the experiments with a model two-section REBCO solenoid cooled by either gaseous helium (GHe) or sub-cooled/solid nitrogen (SN2) in (50-77) K temperature range. The major cooling source was a single-stage cryocooler Sumitomo CH-110 with the cooling power of 175 W and 130 W at 77 K and 50 K respectively. The coil itself was not directly conduction cooled. We compare the time taken by both coolants to obtain the temperature of the magnet of about 50 K and the homogeneity of the temperature distribution within the cryostat. Test results for the coil operation in solid nitrogen together with the comparison of its critical properties in SN2 and GHe are also presented.

• 한국정보과학회 언어공학연구회:학술대회논문집(한글 및 한국어 정보처리)
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• 한국정보과학회언어공학연구회 2022년도 제34회 한글 및 한국어 정보처리 학술대회
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• pp.576-581
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• 2022

감정 분석은 긍부정의 극성을 판단하는 감성 분석과 달리 텍스트로부터 구체적인 감정 유형을 분류해내는 과제이다. 본 논문에서는 소설 텍스트에 감정 분석을 수행하는 것을 새로운 과제로 설정하고, 이에 활용할 수 있는 감정 용언 사전을 소개한다. 이 사전에는 맥락과 상관없이 동일한 감정을 전달하는 직접 감정 표현과 맥락에 따라 다른 감정으로 해석될 수 있는 간접 감정 표현이 구분되어 있다. 우리는 이로써 한국어 자연어처리 연구자들이 소설의 풍부한 감정 표현 텍스트로부터 정확한 감정을 분류해낼 수 있도록 그 단초를 마련한다.

• Asian Pacific Journal of Cancer Prevention
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• 제17권3호
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• pp.1111-1114
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• 2016

Opisthorchiasis is a major problem in Thailand particularly in northeast region which also has a high incidence of cholangiocarcinomas. Since health modification is needed, this quasi-experimental study aimed to assess the effectiveness of a health education program based on self-efficacy and social support in Tha Tum district, Surin province, Thailand. A total of 70 participants were purposive selected with a history of opisthorchiasis. Participants were divided into experimental and control groups, each with 35 subjects. The experimental group received a health education program composed of: (1) knowledge improvement, lectured with multimedia, demonstration, brochure, and handbook; (2) group discussion about their health beliefs, sharing their ideas and experience; and (3) social support from village health volunteers (VHV), heads of villages (HV), friends, and members of families, and public health officer (PHO). Follow-up was by PHO/VHV/HV, with provision of certificates and flasg for household that did not eat raw fish. Data were collected by predesigned questionnaires after implementation of the program for 3 months. Comparative data was analyzed by paired simple t-test and independent t-test. The results revealed that the experimental group had mean score of knowledge higher more than before the experiment (mean difference=3.1, t=3.915, 95%CI-3.3, -1.8 p-value=0.001), and the control group (mean difference=2.5, t=4.196, 95%CI=1.4, 3.6, p-value=0.001) with statistical significance. The mean scores of practice were higher than before the experiment (mean difference=4.6, t=4.331, 95%CI-5.3, -3.1, p-value=0.001), and control group (mean difference=4.4, t=6.142, 95%CI=4.2, 7.9, p-value=0.001). The mean scores of perceived susceptibility and perceived severity of opisthorchiasis, al well as perceived benefits and perceived barriers to prevention of opisthorchiasis, were also higher than before the experiment and in the control group (p-value <0.001). In conclusion, this was a successful health education program for liver fluke avoidance. Therefore, it may useful for further behavior modification in the other epidemic areas.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2004년도 ICCAS
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• pp.879-884
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• 2004

This paper describes the development of a synthetic multi-agent called KMITL Cadence 2003. KMITL Cadence 2003 is a robotic soccer simulation team consisting of eleven autonomous software agents. Each agent operates in a physical soccer simulation model called Robocup Soccer Server which provides fully distributed and real-time multi-agent system environment. All teammates have to cooperate to achieve the common goal of winning the game. The simulation models many aspects of the football field such as noise in ball movements, noisy sensors, unreliable communication channel between teammates and actuators, limited physical abilities and restricted communication. This paper addresses the algorithm to develop the soccer agents to perform basic actions which are scoring, passing ball and blocking the opponents effectively. The result of this development is satisfactory because the successful scoring attempts is increased from 11.1% to 33.3%, successful passing ball attempts is increased from 22.08% to 63.64%, and also, successful intercepting attempts is increased from 88% to 97.73%.

• 한국해양공학회지
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• 제28권1호
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• pp.47-54
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• 2014

When an anchor penetrates and is installed under a seabed, a portion of the mooring line connected to the anchor is also embedded under the seabed. This embedded mooring line affects the capacity of the anchor in two ways. First, the frictional resistance that occurs between the mooring line and the seabed reduces the pulling force acting on the anchor. Second, the embedded part of the mooring line forms a reverse catenary shape due to the bearing resistance of the soil, so that an inclined pulling force is applied to the anchor. To evaluate the mooring line's effect on the capacity of an anchor in sand, centrifuge model tests were performed using two relative sand densities of 76% and 51% while changing the anchor depths. The test results showed that the load is reduced much more in deep and dense sand, and the inclination angle of the load is lower in shallow and loose sand.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.228-228
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• 2006

Conjugated oligomers, used as models for fluorene-thiophene copolymers, are compared in terms of the microscopic morphology of thin deposits and the optical properties. The AFM images and the solid-state absorption and emission spectra are interpreted in line with the structural data, in terms of the assembly of the conjugated molecules. The compound with a terthiophene central unit and fluorene end-groups shows well-defined monolayer-by-monolayer assembly into micrometer-long strip-like structures, with a crystalline herringbone-type organization within the monolayers. Polarized confocal microscopy indicates a strong orientation of the crystalline domains within the stripes. In contrast, the compound with a terfluorene central unit and thiophene end groups forms no textured aggregates. The difference in behavior between the two compounds most probably originates from their different capability of forming densely-packed assemblies of ${\pi-pi}$ interacting molecules. These assemblies are used as active elements in organic field effect transistors designed by using soft lithography technique.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.304-304
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• 2006

The possibility to develop optoelectronic devices with improved properties by controlling the degree of organization at the molecular level of organic materials has been driving the design of new ${\pi}-conjugated$ systems. In particular, the organization by self-assembling processes (${\tilde{\Box}}{\d{\Box}}}$ interactions, hydrogen bonding) of well-defined oligomeric systems such as disubstituted oligothiophene derivatives has been demonstrated as a promising approach to conjugated materials with a high degree of structural order of the constituent building blocks. The self-organization of conjugated building blocks in solution or on surfaces, leading to the construction of nanoscopic and mesoscopic architectures, represents a starting point for the construction of molecular electronics or even circuits, through surface patterning with nanometer-sized objects.

• 한국해양공학회지
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• 제27권1호
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• pp.59-66
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• 2013

A suction anchor is one of the most popular anchors for deepsea floating systems. An anchor used for catenary mooring is predominantly under a horizontal load. In this study, the behavior of a suction anchor installed in cohesionless soil was investigated when the anchor was mainly subjected to a horizontal load induced by a catenary line. In order to study the behavior of the suction anchor, 3D FEM analysis models were developed and analyzed. Depending on the location of the load (padeye), the ultimate horizontal load was monitored. The distributions of the reaction forces around the anchor induced by the seabed were analyzed using the circumferential stress to understand the behavior of the suction anchor under a horizontal load.

• 대한간호학회지
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• 제34권8호
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• pp.1477-1482
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• 2004

Purpose. With the continuous spread of the AIDS virus and other sexually transmitted diseases (STDs) throughout Asia, it has become imperative for HIV/AIDS prevention outreach programs to stress the need for using prophylactics as one form of protection. This is particularly true for commercial sex workers. This pilot study was conducted to investigate the rate of condom use among the commercial sex workers in Korea and reasons why they frequently do not wear condoms during sexual intercourse. Methods. Fifty female commercial sex workers who worked in the Yong San area were recruited while outreach was performed and forty eight responses were analyzed due to two incomplete questionnaires. The data were collected on June 28, 2004 as part of an outreach program for condom use promotion. Results. The subjects ranged in age from 21 to 45 years. Nearly half of the subjects ($47.9\%$) did not consistently use condoms. The major reason for not using protection was clients' reluctances for using condoms. When condoms were used, the subjects preferred lubricant-rich and less painful condom during intercourse. Conclusion. Due to the inconsistent use of condoms, it is clear that many commercial sex workers and clients are susceptible to sexually transmitted diseases. Therefore, it is important to not only educate commercial sex workers, but also to educate their pimps and clientele about the importance of condom use. In general, it is recommended that practical strategies and a policy for condom use promotion be developed.