• Journal of the Korea Institute of Information and Communication Engineering
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• v.23 no.10
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• pp.1261-1268
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• 2019

In this paper, we present the analysis of a novel monopole antenna with a reflector. The proposed monopole antenna is printed on a TRF-45 substrate, and the reflector, which is positioned near the base of the antenna, is printed on the FR-4 substrate. Positioning the reflector near the base of the antenna was found to suppress current radiation toward the back of the monopole antenna. Comparative analysis of the proposed monopole antenna and a conventional monopole antenna without a reflector revealed that the bandwidths of the antenna with and without a reflector were 2.65 GHz and 2.88 GHz, respectively. Additionally, the antenna without a reflector was observed to have a bi-directional radiation pattern in the E-plane, and an omni-directional radiation pattern in the H-plane. However, only the antenna with a reflector was found to suppress back radiation, and provide non-uniform directional radiation in the E-plane and H-plane.

• Korean Journal of Child Studies
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• v.11 no.1
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• pp.72-86
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• 1990

The purpose of this study was to investigate possible differences in the behavior problems of peer-rejected and peer-neglected children in relation to parent and teacher perspectives. The subjects in this study were 239 children and their parents(fathers:37, mothers: 155. father+mother pairs:47) and 10 teachers in the fifth grade of a public elementary school located in Seoul. The sociometric assessment mothods were positive and negative peer nominations. On the basis of this sociometric assessment. children were assigned to one of 4 categories in degree of popularity:65 popular, 53 average. 62 rejected. and 59 neglected children. Parents and teachers rated child behavior on the Achenbach and Edelbrock Child Behavior Checklist(CBCL) for parents and Teacher's Report Form(TRF) were used. The obtained data were analyzed by one-way MANOVA and Duncan Multiple Range Test. Rejected children were found to exhibit more behavior problems than neglected, popular, or average children. Neglected children, however, did not exhibit more behavior problems than chidren of average status.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2001.10a
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• pp.451-455
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• 2001

This study was performed to examine water and nutrient balance during rice cropping period using difference fertilization paddy plot in ground water irrigation region. The experimental rice paddy consist of three plot, Treatment of Excess fertilization(TEF) and Treatment of Standard Fertilization(TSF) and Treatment of Reduce Fertilization(TRF). As result, input amount to rice paddy was almost rainfall and output was direct runoff through drainage. nutrient input amount was upper paddy in case COD and fertilization in case Total nitrogen and total phosphorus, and output was drainage in all nutrient.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2001.02a
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• pp.163-166
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• 2001

KEPCO has a plan to construct TRF (tritium removal facility) in wolsong nuclear power plant site by 2005. In advance of WTRF construction, the pilot plant was installed at KEPRI in order to show process reliability of WTRF. The main processes of this pilot plant are LPCE(liquid phase catalytic exchange) and CD (cryogenic distillation). Deuterium is separated from heavy water in LPCE process and concentrated in CD process. CD process consists of cold box, where are a distillation column and heat exchangers, vacuum system, cryogenic refrigerant supply system and instrument & control system. The experience of the pilot plant will be used in WTRF design review, operating procedure revision and fundamental education for the operators.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.31 no.3 s.258
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• pp.380-387
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• 2007

We carried out an image analysis of living cells forming their contacts at the bottom of the cell culturing substrate. In order to visualize the contact area selectively, we adopted total-internal-reflection-fluorescence (TIRF) method, which can illuminate the specimen volume within only several hundred nano-meters above the substrate. From the fluorescent intensity of the TRF image, we could calculate the distance of the cell surface from the substrate. As a result, we visualized the origin of cell contacts, their movements, and the change of cell-contact type from the close-contact into focal-contact with information of its vertical displacement representing the temporal evolution process of the three-dimensional cell-surface-profile near the contact area during this metamorphosis.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2003.11a
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• pp.484-490
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• 2003

The amount of the tritium released from Wolsong units during the WTRF operation is predicted. The profiles of tritium concentration in moderators and PHTs as variation of WTRF service allotment for each Wolsong unit are calculated, and the tritium releases are obtained from these tritium concentration profiles. The tritium concentration in moderator will be decreased down under 10 Ci/kg in 2013 and the yearly tritium release will be reduced below 25% of WTRF start year.

• Proceedings of the Korea Society for Industrial Systems Conference
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• 2006.05a
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• pp.407-410
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• 2006

최근 들어 반도체의 기술적인 성장과 네트워크의 발전으로 유비쿼터스 컴퓨팅 환경이 대두되고 있으며 이에 따라 RFID라는 신기술이 등장과 응용에 관한 연구가 활발히 진행되고 있다. 이에 본 논문에서는 기존 RFID 시스템에서 유선망을 사용한 데이터 전송으로 인하여 발생될 수 있는 공간 및 이동성의 제약을 극복하기위하여 저가의 무선전송모듈을 적용하여 휴대형 상품정보제공 시스템을 개발하였다. 무선전송 모듈은 900MHz 대역의 Texas Instruments 사의 TRF6901 chipset을 이용하였고, 이를 제어하는 MPU는 TI사의 MSP430F149로 설계하였다. 본 논문에서 개발한 시스템은 도서관리, 출입통제 시스템등에 범용적으로 적용될 수 있을 뿐 아니라 핸드 헬드형 RFID 시스템에 혁신적인 기대 효과를 예상할 수 있다.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.11 no.5
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• pp.684-691
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• 1999

A load calculation program based on TFM(Transfer function method) has been proposed in this study. The validity of the current method has been verified by comparing heat gain calculation by TRF(Thermal response factor) with that by CTF(Conduction transfer function) adopted in ASHRAE. In addition, it seems that the CTF coefficients given in ASHRAE tables have somewhat ambiguity The load calculation program developed in the current study has been employed to calculate cooling load from the exterior walls and roof of example 6 in the ASHRAE. The results are found in good agreement.

• Journal of Music and Human Behavior
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• v.6 no.1
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• pp.33-53
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• 2009

The purpose of this study is to examine the effects of a singing program on withdrawal behaviors of children in low-income families. To measure the effects of the singing program, the researcher compared the results of K-YSR and TRF withdrawal scales before and after the program. Finally, the researcher did research on the subjects' musical and non-musical behaviors related to withdrawal through a record of behavior observation. The results of this study were asfollows: First, after comparing the results of K-YSR and TRF withdrawal scales conducted before and after the singing program, the mean of the scores was decreased by 6.4 and 3.6 points respectively (p = .042). Second, an analysis of withdrawal-related behavioral changes in music activities after the program showed an increase in frequency of eye contact, as well as tone and volume of subjects' voices. The results of this study indicate that the singing program has positive effects on withdrawal behaviors of children in low-income familiesin addition, it is effective in alleviating withdrawal-related behaviors.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.5 no.2
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• pp.155-169
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• 2007

A transport container for a 500 kCi tritium storage vessel was developed, which could be used for the transport of metal tritide from Wolsong TRF facility to a disposal site. The structural, thermal, shielding, and confinement analyses were performed for the container in a view of Type B. As a result of structural analysis, the developed container sustained its integrity under normal and accidental conditions. The maximum temperature increase of the inner storage vessel by radiation was evaluated at $134.8^{\circ}C at room temperature. In $800^{\circ}C$ fire test, The thermal barrier of container sustained the inner vessel at $405^{\circ}C after 30 min, which temperature was allowable for the container integrity since maximum design temperature of inner vessel was $550^{\circ}C. In the evaluation of the shielding, the activity of radiation was nearly zero on the outer surface of inner vessel. Consequently the transport container for a 500 kCi tritium was evaluated to pass all the safety tests including accidental condition, so it was concluded that the designed transport container is proper to be used.