• 한국가축번식학회지
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• 제8권1호
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• pp.10-15
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• 1984

This experiment was carried out to study the egg transports and distribution patterns in the oviducts of superovulated rabbits by administrations of PGF2$\alpha$. Group I (3 does) and Group II (3 does) were killed at 24 hours, 48 hours after mating, respectively. Group III (6 does0 received a single injection of 5mg/Kg of body weight of PGF2$\alpha$ at 24 hours after mating and killed at 4 hours after PGF2$\alpha$ administration. The oviducts were frozen in LN-gas, thawed using Howe's method, and cleared in Benzyl-Benzoate sol. using Orsini's technique. The location of the eggs and the AIJ. were identified using transmitted light from a dissecting microscope. The results obtained were as follows: 1. The average numbers of detected eggs from the oviduct were 28.6 (26-32), 26.0 (24-29), and 27.1 (22-34) in Group I, II, and III, respectively. 2. Detection rate was 88.7%, 76.4%, and 84.9% in Group I, II, and III, respectively. 3. The positionof all AIJ. was 44.2% to 55.0%(av. 49.5%) of the distance from the fimbriae to the UTJ.(Utero-Tubal Junction). 4. The changes of egg distribution patterns were as follows: Group I Ampulla : 52.3%, Isthmus : 47.7%, Group II Ampulla : 8.9%, Isthmus : 91.1% Group III Ampulla : 8.0% Isthmus : 92.0%.

• 원예과학기술지
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• 제35권1호
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• pp.79-87
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• 2017

We examined the effect of two greenhouse covering materials (glass or solid polycarbonate sheets) on the light environment and growth of tomato and cucumber plants. Spectral analysis showed that polycarbonate sheets entirely blocked radiation in both the UV - B (300 - 320 nm) and UV - A (320 - 400 nm) ranges, whereas glass transmitted UV - A and was only opaque to UV - B. The transmittance of photosynthetically active radiation (400 - 700 nm) and near infrared radiation (700 - 1100 nm) was higher in polycarbonate than glass. Air and soil temperatures were not significantly different between greenhouses covered with either material. The growth of cucumber plants was slightly affected by covering materials, whereas no significant changes in growth parameters were observed for tomato plants. The color parameters of tomato fruits were affected by the cover material, whereas cucumber fruits showed similar coloration in both glass and polycarbonate greenhouses.

• E2M - 전기 전자와 첨단 소재
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• 제8권2호
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• pp.190-195
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• 1995

Temperature dependences of the dielectric constant K(T), remanent polarization $P_{r}$, (T), effective birefringence overbar .DELTA.n(T), transmitted light intensity and quadratic electro optic coefficient R(T) of the two-stage sintered xBa(L $a_{1}$2/N $b_{1}$2/) $O_{3}$-(1-x)Pb(Z $r_{y}$ $Ti_{1-y}$) $O_{3}$(x=0.085, 0.09, 0.40.leq.y.leq.0.70) ceramics were investigated. Increasing the PbZr $O_{3}$ contents, the crystal structure of a specimen was changed from a tetragonal phase to a rhombohedral and cubic phase, and the phase transition was showed a diffuse phase transition(DPT) characteristics. In the compositions which located on the PE-FE phase boundary, the discrepancy was observed between the Curie temperature and temperature which a microscopic polarization and effective birefringence were disappeared.red.d.

• 한국인터넷방송통신학회논문지
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• 제12권1호
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• pp.181-187
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• 2012

LED는 빛을 내는 반도체 이다. 최근 친환경적 산업이 발전함에 따라 LED조명의 연구가 활발하게 진행되어 가고 있다. 특히 LED를 이용한 통신기법인 LED 통신에 대한 활발한 연구가 진행 중이다. 본 논문에서는 LED 통신을 이용한 PC-PC 전송시스템을 구현하였다. LED를 이용한 송신부 회로구성 및 PD와 OP-Amp를 이용한 수신부 회로를 구성하였다. 실험은 다음처럼 진행되었다. 송 수신부 양 끝단에 컴퓨터를 연결한 다음, 텍스트 전송프로그램을 이용하여 텍스트를 전송하였다. 이때 보드 레이트(baud rate), LED 색깔, 전송거리 등 다양한 변화를 주면서 실험을 진행하였다.

• Nuclear Engineering and Technology
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• 제42권1호
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• pp.9-16
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• 2010

Experimental examinations for evaluating fracutres were conducted by using transparent replicas of a single fracture in order to obtain the fracture data to contribute to the methodlogy on how to improve the definitaion of representative parameter values used for a parallel plate fracture model. Quantitative aperture distribution and quantitative tracer concentration data at each point in time were obtained by measuring the attenuation of transmitted light through the fracture in high spatial resolution. the representative aperture values evaluated from the multiple different measurement methods, such as arithmetic mean of aperture distribution measured by the optical method, transport aperture evaluated from the tracer test, and average aperture evaluated from the fracture void volume measurement converged to a unique value that indicates the accuracy of this experimental study. The aperture data was employed for verifying the numerical simulation under the assuption of Local Cubic Law and showed that the calculated flow rate through the fracture is 10%-100% larger than hydraulic test results. The quantitative tracer concentration data is also very valuable for validating existing numerical code for advection dispersion transport in-plane heterogeneous fractures.

• 전자통신동향분석
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• 제36권3호
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• pp.97-105
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• 2021

The terahertz wave (THz wave) is a band between infrared and microwaves and is defined as an electromagnetic wave having a frequency of 0.1 to 10 THz band. THz waves have the property of transmitting nonpolar materials, which the visible light cannot be transmitted, such as ceramics, plastics, and paper; and the photon energy is low, such as several meV. For this reason, non-destructive testing equipment based on THz imaging technology can be applied to the industrial field. Recently, THz imaging technology was applied in wide industrial fields, such as automobiles, batteries, food, medical, and security, and being actively studied. In this paper, we describe the research trends of terahertz imaging technology and experimental results. Furthermore, we summarize the recent commercialized terahertz camera. Finally, we present the research results in the field of the human security scanner system.

• Journal of Advanced Research in Ocean Engineering
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• 제4권4호
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• pp.146-162
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• 2018

The unsteady problem of a rigid body impact onto a floating plate is studied. Both the plate and the water are at rest before impact. The plate motion is caused by the impact force transmitted to the plate through an elastic layer with viscous damping on the top of the plate. The hydrodynamic force is calculated by using the second-order model of plate impact by Iafrati and Korobkin (2011). The present study is concerned with the deceleration experienced by a rigid body during its collision with a floating object. The problem is studied also by a fully-nonlinear computational-fluid-dynamics method. The elastic layer is treated with a moving body-fitted grid, the impacting body with an immersed boundary method, and a discrete-element method is used for the contact-force model. The presence of the elastic layer between the impacting bod- ies may lead to multiple bouncing of them, if the bodies are relatively light, before their interaction is settled and they continue to penetrate together into the water. The present study is motivated by ship slamming in icy waters, and by the effect of ice conditions on conventional free-fall lifeboats.

• 반도체디스플레이기술학회지
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• 제17권3호
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• pp.70-74
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• 2018

In typical spectroscopic ellipsometry, the optical and geometrical properties of thin film and nano pattern can be obtained by measuring the polarization state of light reflected/transmitted from the object by rotating a analyzer or a compensator. We proposed a snapshot spectroscopic ellipsometric system based on a modified Michelson interferometer to overcome the time-consuring measurement principle due to rotating part. The proposed system provides spectral ellipsometric parameters (psi, delta) in real time by using a single spectral interference signal generated in the interferometric polarization module. However, it has a long-term stability problem resulting in delta(k) drift. In this paper, it is experimentally proved that the drift problem is caused by anisotropic refractive index change of the beam intersection layer in beam splitter of interferometer.

• Current Photovoltaic Research
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• 제11권1호
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• pp.34-37
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• 2023

Solar energy had become the main energy industry of renewable energy along with hydroelectric power generation. One of the technologies that contributed to the popularization of photovoltaic power and the decrease in the unit price of photovoltaic modules was the large-area solar cell. However, as the area increased, the light receiving area increased and the current value increased accordingly. Since power loss occurs when the current value was large, the number of busbar was increased to increase the current collection rate, and a technology to lower the current value through half-cutting was developed. The bus bar of the solar cell served as a passage through which the generated current was transmitted. This was because when the number of busbar decreases, the moving distance of electrons increased, so the amount of power generation decreases and when it increases, shadows occured. An important aspect of the electrode design was the optimal balance of these busbars and number of fingers. Therefore, in this study, the characteristics of the solar cell according to the number of front bus bars of the large-area solar cell were simulated using Griddler 2,5 pro. After selecting the number of busbar with the best characteristics, the difference was compared by varying the number of fingers and a better direction for the number of cutting was presented.

• International journal of advanced smart convergence
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• 제12권4호
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• pp.458-463
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• 2023

This study presents a paper on the implementation of a Raspberry Pi-based educational smart farm system. It confirms that in a real smart farm environment, the control of temperature, humidity, soil moisture, and light intensity can be smoothly managed. It also includes remote monitoring and control of sensor information through a web service. Additionally, information about intruders collected by the Pi camera is transmitted to the administrator. Although the cost of existing smart farms varies depending on the location, material, and type of installation, it costs 400 million won for polytunnel and 1.5 billion won for glass greenhouses when constructing 0.5ha (1,500 pyeong) on average. Nevertheless, among the problems of smart farms, there are lax locks, malfunctions to automation, and errors in smart farm sensors (power problems, etc.). We believe that this study can protect crops at low cost if it is complementarily used to improve the security and reliability of expensive smart farms. The cost of using this study is about 100,000 won, so it can be used inexpensively even when applied to the area. In addition, in the case of plant cultivators, cultivators with remote control functions are sold for more than 1 million won, so they can be used as low-cost plant cultivators.