• Asian-Australasian Journal of Animal Sciences
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• 제10권4호
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• pp.435-438
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• 1997

Twelve newborn goat kids born of philippine does (3.5 and 5 years old) were used in this study. Four mother (candidate) doe goats were randomly allocated to each group. The mother does were infected orally with three levels (0, 15,000 and 30,000 larvae) of infective Haemonchus contortus larvae. Before infection all animals were housed in individual pens with concrete floors. They were provided with a uniform management. Estrus of does were synchronized using PGF2 alpha. All the animals were bred naturally by the same buck. Baby goat born of infected mother goats were divided into three groups. $T_1$, $T_2$ and $T_3$), respectively, from mother treatment groups. Birth weight and growth of goat kids born from H. contortus infected mother goats were determined. Birth weights of kids of $T_1$, $T_2$ and $T_3$ were 1.9, 1.5 and 1.2 kg, respectively. No significant (p > 0.05) differences in birth weight of kids for the 3 treatment groups were found. However, significant (p < 0.05) effects of stomach worm infection and duration of infection on liveweight gain of kids were observed. After second and third week of birth, respectively, the kids of groups 3 and 2 registered lover liveweight gains than the kids in control group. However, no significant (p > 0.05) difference in liveweight gain was found between the kids of infected mother does. Fecal egg counts of the infected mother does showed patent infections which also indicated by postmortem worm counts. However, no worm egg was found in the feces of the test kids.

• 한국정보처리학회논문지
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• 제3권2호
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• pp.305-314
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• 1996

B-ISDN망은 ATM방식으로 멀티미디어 정보를 전송하고자 할 때, 발생될 수 있는 셀의 종류로써 미디어 정보를 갖고 있는 미디어셀과 동기 정보를 갖고 있는 동기셀로 각각 분리하였다. 트래픽 입력원을 NO-OFF 발생원으로 하는 Leaky Buck에서 확률 분포 함수를 기반으로 한 미디어셀 손실식과 동기셀 손실식을 유도하였다. 멀티미디어 동기셀은 종기 정보의 무결성과 실시간 요건을 만족시키기 위해서는 지연 민감 요건과 손실 민감 요건을 모두 갖추어야 한다. 이러한 요건을 만족 시키기 위해 우선 순위 제어 기법이 필요할 트래픽 모델링 시뮬레이션을 통해 성능 평가한 걸과, 동기셀 손실 효과 를 최소화할 수 있는 공간 우선 순위 제어 기법과 동기셀 지연 효과를 최소화할 수 있는 시간 우선 순위 제어 기법을 동시에 적용하여야 하는 필요성을 제시하였다.

• Transactions on Electrical and Electronic Materials
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• 제17권2호
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• pp.57-68
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• 2016

In this study, we present the modern hybrid system based power generation for electric vehicle applications. We describe the hybrid structure of modified current source based DC - DC converters used to extract the maximum power from Photovoltaic (PV) and Fuel Cell system. Due to reduced dc-link capacitor requirement and higher reliability, the current source inverters (CSI) better compared to the voltage source based inverter. The novel control strategy includes Distributed Maximum Power Point Tracking (DMPPT) for photovoltaic (PV) and fuel cell power generation system. The proposed DC - DC converters have been analyzed in both buck and boost mode of operation under duty cycle 0.5>d, 0.5<d<1 and 0.5<d for capable electric vehicle applications. The proposed topology benefits include one common DC-AC inverter that interposes the generated power to supply the charge for the sharing of load in a system of hybrid supply with photovoltaic panels and fuel cell PEM. An improved control of Direct Torque and Flux Control (DTFC) based induction motor fed by current source converters for electric vehicle.In order to achieve better performance in terms of speed, power and miles per gallon for the expert, to accepting high regenerative braking current as well as persistent high dynamics driving performance is required. A simulation model for the hybrid power generation system based electric vehicle has been developed by using MATLAB/Simulink. The Direct Torque and Flux Control (DTFC) is planned using Xilinx ISE software tool in addition to a Modelsim 6.3 software tool that is used for simulation purposes. The FPGA based pulse generation is used to control the induction motor for electric vehicle applications. FPGA has been implemented, in order to verify the minimal error between the simulation results of MATLAB/Simulink and experimental results.

• 한국항공우주학회지
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• 제42권11호
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• pp.981-987
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• 2014

DC/DC 컨버터는 임의의 직류전원을 부하가 요구하는 형태의 직류전원으로 변환시키는 효율이 높은 전력변환기이다. DC/DC 컨버터는 MOSFET(산화물-반도체 전계 효과 트랜지스터), PWM-IC(펄스폭 변조 집적회로) 제어기, 인덕터, 콘덴서 등으로 구성되어있다. MOSFET는 스위치 기능을 수행하는데 코발트 60 ($^{60}Co$) 저준위 감마발생기를 이용한 TID 실험에서 방사선의 영향으로 문턱전압과 항복전압의 변화와 SEGR 실험에 적용된 5종류의 중이온 입자는 MOSFET의 게이트(gate)에 영향을 주어 게이트가 파괴된다. MOSFET의 TID 실험은 40 Krad 까지 수행하였으며, SEGR 실험은 제어보드를 구현한 후 LET(MeV/mg/$cm^2$)별 cross section($cm^2$)을 연구하는데 있다.

• 가정과삶의질연구
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• 제22권4호
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• pp.43-61
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• 2004

The purpose of this study was to verify the usefulness of kinetic House- Tree- Person drawing as a diagnostic measure for the degree of self-differentiation, which is an essential part of college students' development. Participants for the study were four hundred thirty five(272 male and 163 female) university freshmen enrolled in 4-year colleges located in Pusan. The Participants completed a scale of self-differentiation and a Kinetic House- Tree-Person drawings test. The evaluation system for kinetic House-Tree-Person drawings was established based on the indexes of Buck(1948) and Bums(1972) and used exiting literatures as reference. The data were analyzed using means, standard deviations, t-test, one-way ANOVA, and Scheffe's test. The results obtained from the study are as follows: First, the mean level of college students' self-differentiation was 2.81, which is about average. Some significant gender differences were found in the areas of self-intergration, family projection, and emotional separation. Male students scored higher on self-intergration, whereas female students score higher on family projection and emotional separation. Second. self-differentiation was higher when the student drew a house with smoke coming out of the chimney, a single-story house with flat roof, or with detailed description of curtains, roof and roof tiles. Third, self-differentiation seemed to be higher when branches and fruits were included, when there was no expression of roots, when large crowns and branch openings were presented, and when no slant lines or base lines appeared. Forth, self-differentiation showed ㅁ higher level when the portrait shows eyes, mouth and neck without omission, when it included the whole body instead of face only, and when there was no person with just a profile, a back, or with a stiff posture, and when there was no weak and thin lines. Individuality also marked higher if a person was in motion and than one person was added. Finally, self-differentiation showed significant difference according to the overall harmony of the drawing, ordering of contents, hand pressure, the kind and shape of tree, and presence of other persons. The more harmonious the picture was, and the more family members are added, the higher the level of self-differentiation was.

• 전자공학회논문지SC
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• 제40권1호
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• pp.39-44
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• 2003

휴대용 전자기기가 많이 개발되고 보급됨에 따라서 배터리의 중요성은 점점 커져가고 있다. 기기의 수명을 늘이고자 고전력밀도의 배터리를 요구하게 되었고, 현재에는 리튬-이온 배터리를 많이 사용하게 되었다. 단위체적 및 중량당의 전력밀도 부분에서는 기존에 사용하던 배터리보다 성능이 우수하지만, 방전전압이 감소하는 특성이 있기 때문에 배터리의 수명을 최대한 늘리기 위해서는 이 특성에 알맞은 컨버터가 필요하다. 그래서 리튬-이온 배터리를 사용하는 휴대용 저전력 전자기기의 전원부로써 용량성 아이들링 SEPIC을 제안하였다. 승압과 강압이 가능한 SEPIC의 특성을 가지면서, 추가된 스위치와 다이오드를 통해서 스위치에 부분적인 소프트 전환을 가능하게 하기 때문에, 스위칭 주파수의 증가를 가능하게 한다. 본 논문에서는 직류 정상상태의 전압전환비, 동작모드별 회로 및 회의특성을 분석하고 구현하였다.

• 한국사회복지학
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• 제63권4호
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• pp.183-202
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• 2011

본 연구는 여성결혼이민자의 근로유무가 정신건강에 미치는 영향을 한국어사용능력과 거주기간을 사회적응 매개변수로 하여 그 영향력을 살펴본 연구이다. 서울과 인천, 경기지역에 거주하는 총 247명의 여성결혼이민자를 대상으로 설문지를 통해 조사가 진행되었으며, 분석방법은 빈도 및 기술분석과 매개 효과 검증을 위한 경로분석을 진행하였다. 분석결과 여성결혼이민자의 근로유무는 정신건강에 직접적인 영향을 미치며 사회적응은 근로유무가 정신건강에 미치는 영향을 완전매개하는 것으로 나타났다. 즉, 여성결혼이민자의 근로활동은 사회적응을 높이고 이를 통해 정신건강을 증진시키는 것으로 나타났다. 그러므로 여성결혼이민자의 정신건강 증진을 위한 근로활동지원 및 언어능력 향상을 위한 사회적 지원체계 마련이 필요하다 하겠다.

• 한국축산식품학회지
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• 제34권4호
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• pp.457-463
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• 2014

The effects of feeding of diets based on roughage supplemented with concentrate on the carcass and meat quality attributes of Korean black goats were investigated. The 40 male goats at 5 mon age were divided into four treatment groups; T1 (1.5%), T2 (2.0%), T3 (2.5%) and T4 (ad libitum) feeding of concentrate with ad libitum rice straw. Forty bucks at the end of the feeding were fasted for 12 h before slaughter and were then slaughtered. For carcass measurement, cold buck carcasses were examined after 24 h of chilling at $5^{\circ}C$. The carcasses were chilled in refrigerator at $2{\pm}2^{\circ}C$ for 24 h, then the longissimus dorsi muscle was removed from the carcasses. The samples were separately vacuum packaged, frozen and stored at $-20^{\circ}C$ for up to 1 mon, prior to physicochemical evaluations. Carcass yields were greatly affected by rate of concentrate feeding. T4 showed the heaviest live and carcass weights and the highest dressing and fat percentages (p<0.05). The moisture contents were lower in T4 compared with other treatments, while the crude protein and fat contents were higher (p<0.05). mono-unsaturated fatty acid in T4 was significantly higher than others, which showed the highest percentages of oleic acid (C18:1). For the sensory test, T4 was tenderer and produced better flavor scores than others. Increasing the level of concentrate in the diet resulted in an improvement in growth performance, and carcass and physicochemical characteristics of goat meats.

• 제어로봇시스템학회논문지
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• 제21권10호
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• pp.910-916
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• 2015

A sensorless motor control scheme with conventional back-Electro Motive Force (EMF) sensing based on zero crossing point (ZCP) detection has been widely used in various applications. However, there are several problems with the conventional method for effectively driving sensorless brushless motors. For example, a phase mismatch of 30 degrees occurs between the ZCP and commutation time. Additionally, most of the motor speed/current controls are achieved based on a pulse width modulation (PWM) method, which generates significant noise that distracts the back-EMF sensing. Due to the PWM switching, the ZCP is not deterministic, and thus the efficiency of the motor is reduced because the phase transition points become uncertain. Moreover, the motor driving performance is degraded at a low speed range due to the effect of PWM noise. To solve these problems, an improved back-EMF detection method based on a differential line method is proposed in this paper. In addition, the proposed sensorless BLDC driver addresses the problems by using a variable voltage driver generated from a buck converter. The variable voltage driver does not generate the PWM switching noise. Consequently, the proposed sensorless motor driver improves 1) the signal-to-noise ratio of back-EMF, 2) the operation range of a BLDC motor, and 3) the torque characteristics. The proposed sensorless motor driver is verified through simulations and experiments.

• 한국응용곤충학회지
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• 제14권2호
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• pp.77-79
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• 1975

우리나라에서 Phytophthora capsici균에 의한 가지의 병해는 아직 그 발생이 보고되어 있지 않다. 근래 수원을 포함한 중부지방에 P. capsici균에 의한 피해과가 채집되어 기록병해인 P. parasitica균에 의한 솜털역병과 그 병징, 병원성 및 병원균의 형태등을 비교 검토하였다. 본 병은 9월 강우가 있은 후 발생이 심하였으며 처음 과면에 원형갈색의 병반이 나타나 점차 확대되면서 그 위에 짧은 균계와 분생자경이 밀생하고 유주자양이 풍부히 형성되어 솜털모양으로 공중균계가 길게 자라고 유주자양이 거의 형성되지 않는 솜털병역과는 구별되었다. 그리고 병원균의 형태 및 병원성에 있어서도 뚜렷한 차이를 볼 수 있었다. 따라서 본 병원균은 P. capsica임을 확인할 수 있었으며 미기록인 본병해에 대하여 가지갈색썩음병이라는 이름을 붙이기로 하였다.