• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2005년도 전기학술대회논문집
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• pp.528-533
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• 2005

This paper presents the study of flows at T-junction pipe with orifices. Experiments were carried out for several flow rates, orifice sizes, and pressure differences. Numerical simulations were also done to get more data for the wide range of flow rates. Experimental results and numerical ones are in a good agreement. Due to the effect of T-junction part, the flow rates at the lateral pipe are greater than those at straight pipe for the same pressure differences. When orifices were added, the effects of T-junction part on the ratio of flow rates and the ratio of loss coefficients reduced.

• 대한간호학회지
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• 제41권3호
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• pp.285-293
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• 2011

Purpose: In this study, the effects of laughter therapy on levels of depression, quality of life, resilience and immune responses in breast cancer survivors were examined. Methods: A quasi-experimental nonequivalent control group, pretest-posttest design was used. Participants (n=37) included breast cancer survivors who finished chemotheraphy and radiation therapy: 16 in the experiment group and 21 in the control group. Data were collected from August to November 2009. The experimental group participated in laughter therapy eight times, twice a week for 60 min per session. Questionnaires were used to me-asure pretest and posttest levels of depression, quality of life and resilience. A blood test was used to analyze changes in Total T cell, T helper, T suppressor, Th/Ts ratio, Total B cell, T cell/B cell ratio and NK cell for immune responses. Results: The results showed that laughter therapy was effective in increasing the quality of life and resilience in breast cancer survivors. but depression and immune responses did not differ significantly between the groups. Conclusion: The results of the study indicate that laughter therapy may be an effective nursing intervention to improve quality of life and resilience in breast cancer survivors.

• 환경생물
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• 제35권1호
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• pp.64-82
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• 2017

Two species of the minuta-subgroup within the oncaeid copepod genus Triconia $B{\ddot{o}}ttger$-Schnack, 1999 collected in the equatorial Pacific Ocean are newly recorded. A female T. minuta (Giesbrecht, 1893 ["1892"]) and both male and female T. umerus ($B{\ddot{o}}ttger$-Schnack and Boxshall, 1990) from the northeast equatorial Pacific are redescribed with the comparison of its morphological details, which differs from previous studies, in terms of the larger body size, the length to width ratio of the genital double-somite, the relative length of the outer basal seta on P5, and the ornamentation of the appendages. The characters, which are used for identification, such as the length ratio of the outer subdistal and outer spine versus the distal spine on P3-P4, and the outer spine length of the middle exopodal segment on P3 and P4 are reported for the first time. Information on the variations in the endopodal spine lengths of swimming legs 2-4 is also provided for T. minuta and T. umerus, with the summary of the wide zoogeographical distribution of these two species.

• 한국항해항만학회지
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• 제39권2호
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• pp.99-105
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• 2015

Until recently, thermal power plants have used high-rank coals to generate electricity. The switched to low-rank coals, primarily because of the rising coal price and the advancement of combustion technology. Therefore the thermal power plants need more fuels aspect of quantity and they are going to build extra infrastructure to deal with the increased fuel demand in their specialized ports. This paper introduces the process of the economic analysis as a case study for Hadong T/P(Thermal Power) Port. This study also evaluates investment for mew projects in ports. We analyze the costs and benefits of the port investment project using various information. And then we conduct the economic analysis using NPV(net present value), B/C ratio and IRR grounded in a financial theory. Out result of the economic feasibility shows that the new project of constructing a third berth in Hadong T/P Port has positive economic value. Additionally, this study conducts the sensitivity analysis of the major variables like cost, benefit and discount rate.

• 한국항행학회논문지
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• 제14권2호
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• pp.170-175
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• 2010

본 논문은 UHF RFID 시스템을 위해 편파를 선택할 수 있는 리더 안테나를 설계 및 구현하였다. 제안된 리더 안테나는 두 개의 급전부를 가지는 마이크로 스트립 패치 안테나와 두 개의 SPDT 스위치와 하나의 SP4T 스위치와 3dB hybrid coupler로 구성되어 있다. 각각의 스위치 전압을 조절하여 수직 방향의 선형 편파와 수평방향의 선형 편파, 좌수 원형 편파와 우수 원형 편파를 선택할 수 있다. 제안된 안테나는 902MHz ~ 928MHz 대역에서 VSWR 2:1을 만족하고 원형 편파로 선택되었을 때 AR (Axial Ratio)은 3dB 이하로 측정되었다. 또한 사용 환경 및 태그의 편파 방향에 적합한 편파를 선택할 수 있기 때문에 PLF (Polarization Loss Factor)를 최소화 할 수 있고 태그의 인식거리를 확장 시킬 수 있다.

• 천문학회지
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• 제17권1호
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• pp.23-36
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• 1984

From the PDS scanning, isophote maps and surface luminosity distributions for the late type spiral galaxy NGC 6946 were obtained. Surface luminosity distribution showed that this galaxy can be classified as the Freeman's type II, and the deep spheroidal component was caused as a result of the ring structure in the central part of NGC 6946. Physical parameters-total magnitude ($M_T^B$), effective radius ($R_e^*$), central surface magnitude $U(0)_{CD}$, length scale (${\alpha}^{-1}$), disk-to-bulge ratio (D/B) and mass-to-luminosity ratio (M/L)-were also calculated, and the results show that NGC 6946 belongs to Sc I type galaxy according to the DDO classification, and is to be a fair sample of classification statge T=6.

• Geomechanics and Engineering
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• 제2권1호
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• pp.29-44
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• 2010

Vertical vibration tests were conducted using model footings of different size and mass resting on the surface of finite sand layer with different height to width ratios which was underlain by either rigid concrete base, under both dry and saturated condition. The effect of saturation on the damping ratio of finite sand stratum underlain by a rigid base has been verified and compared with the results obtained for the case of finite dry sand stratum underlain by the rigid base. Comparison of results of the experimental study showed that the damping in both the cases is less than 10%. The damping ratio obtained for finite saturated sand stratum is marginally lower than that obtained on finite dry sand stratum at H/B ratio of 0.5. The difference between the two cases becomes significant when the H/B ratio increases to 3.0, indicating the significant influence of soil moisture on damping ratio of foundation- soil system with increase in the thickness of the finite sand stratum. Comparison of the predicted damping ratio for a homogeneous sand stratum with the experimental damping ratio obtained corresponding to the height to width ratio of 3.0 of the finite sand stratum underlain by the rigid concrete base indicates a significant reduction in damping ratio of the foundation-soil system for both the cases.

• 한국산림과학회지
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• 제99권6호
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• pp.808-815
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• 2010

본 연구의 목적은 오미자를 새로이 재배하고자 하는 사람들이나 재배면적을 늘이고자 하는 사람들에게 오미자의 경영실태 및 소득과 투자 수익성을 분석하여 투자에 대한 정보를 제공하고자 하는 것이다. 수익성 분석기법으로 IRR, B/C Ratio, NPV를 이용하였다. 오미자 주산단지인 강원도 인제, 경북 문경과 전남 화순 그리고 경남 산청지역의 총 51가구의 오미자 재배농가를 대상으로 2009년 5월부터 9월까지 작업공정별 투입노동 및 자재비 등에 관해 면접방문조사를 실시하였다. 산지가격인 5,000원~6,000원/kg을 바탕으로 kg당 3가지 출하가격 5,000원, 5,500원, 6,000원의 시나리오별 IRR, B/C Ratio 그리고 소득율 등을 구하였다. 할인율은 3.00%를 적용하였다. 그 결과 3가지 시나리오 모두 IRR이 -16.00%, -6.91%, 0.40% 그리고 B/C Ratio가 0.81, 0.89, 0.97로 나타나 투자수익성이 없는 것으로 나타났다. 그러므로 IRR = 3.00%, B/C Ratio = 1.00을 충족하는 오미자 판매가격 6,200원/kg이상이 되어야 수익성이 있다고 판단되며, 이 때의 소득율은 23.9%인 것으로 나타났다.

• 대한전자공학회논문지
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• 제18권3호
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• pp.21-24
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• 1981

Micro-torch를 사용하여 두 개와 taper를 동시에 제작하고, fusion splicing에 외해 광섬유 t-branch률 제작하였다. Y-branch의 insertion loss는 2.6dB, branching율은 0.98까지 얻을 수 있었다. 또 Y-branch를 OTDR의 제작에 응용하여 광학계를 대폭 간소화 하였으며, 길 이 측정오차 ±5m, 손실 측정오차 ±0.5bB/km로 광섬유의 특성을 측정할 수 있었다.

• 한국자기학회지
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• 제8권1호
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• pp.21-26
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• 1998

온도에 따른 비정질 금속 Co66Fe4Ni1B14Si15의 자기 임피던스의 변화를 저온 장치를 써서 시료의 온도를 10K∼300K까지 변화시키면서 측정하였다. 이때, 시료에 겉어준 교류전류를 10mA로 고정시키고 주파수를 100KHz에서 10MHz 까지 변화시켰다. MIR (Magneto-Impedance Ratio)은 온도가 증가함에 따라 급격히 증가하였으며, MIR(T)≡MIR(0)exp(cT2)의 관계식으로 나타났다. 상온에서 측정한 MIR 값은 측정 주파수내에서 10K에서의 값보다 2∼3배 크게 나타났다. 이 결과는 MI 온도 효과를 이용한 온도 센서로서의 가능성을 제시한다. MIR 곡선의 모양은 온도의 증가에 따라 큰 변화가 없었으며 MIR은 주파수 증가에 따라 커지면서 MIR 곡선의 모양이 퍼지는 전형적인 경향을 나타냈다.