• Journal of Communications and Networks
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• 제18권6호
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• pp.902-912
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• 2016

Recent advances in energy harvesting (EH) technology have motivated the adoption of rechargeable mobile devices for communications. In this paper, we consider a point-to-point (P2P) wireless communication system in which an EH transmitter with a non-ideal rechargeable battery is required to send a given fixed number of bits to the receiver before they expire according to a preset delay constraint. Due to the possible energy loss in the storage process, the harvest-use-and-store (HUS) architecture is adopted. We characterize the properties of the optimal solutions, for additive white Gaussian channels (AWGNs) and then block-fading channels, that maximize the energy efficiency (i.e., battery residual) subject to a given rate requirement. Interestingly, it is shown that the optimal solution has a water-filling interpretation with double thresholds and that both thresholds are monotonic. Based on this, we investigate the optimal double-threshold based allocation policy and devise an algorithm to achieve the solution. Numerical results are provided to validate the theoretical analysis and to compare the optimal solutions with existing schemes.

• 한국임상수의학회지
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• 제4권2호
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• pp.463-472
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• 1987

Although there are many reports on the bovine electroacupuncture anesthesia, its application to clinical cases needs much to be verified. In order to apply the electroacupuncture anesthesia to bovine species, a new anesthesia technique, which is safe and effective, must be developed. In the present study, 11 meridian points were selected and 11 kinds of meridian points were prescribed to develop an effective and safe electroacupucture methods in the bovine species. The results obtained are summarized as fellows : 1. When the maximun electric current (30Hz at 5.3-5.6V ) was applied, anesthesia was attained with the signs of tetany and tremor : When the electric current was continued for 15-20 minutes, the signs of tetany and tremor diminished markedly. 2. If the electric current was adjusted to 30Hz at 3.5-4.0V and continued, the tetany and tremor disappeared. The skin was slackened, thus suitable for surgical operation. The continuation of anesthesia could be regulated at operator's own will. 3. The same anesthesia effect could be attained by using any one meridian point when the points were symmetrical. 4. Transient changes of clinical signs and blood pictures were noted during the stages of acupuncture anesthesia. However, the red blood cell counts, white blood cell counts and hematocrit values were always within the normal range.

• 약학회지
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• 제45권3호
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• pp.310-319
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• 2001

To compare skin irritation and cytotoxicity of anti-wrinkle agents, we examined skin irritation of six anti-wrinkle agents (ascorbic acid, glycolic acid, all trans-retinoic acid, ginseng extract, retinol, EB) in New Zealand white rabbit. Cytotoxicity of these agents was determined by MTT [tetrazolium salt 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide] at multi-time points in cultured HaCaT cell, a human immortalized keratinocyte cell. We then analyzed correlation between skin irritation and cytotoxicity by spearman's rank correlation analysis. All trans-retinoic acid showed the highest primary irritation index (0.92) in skin irritation test. Being all the six agents not irritant, retinal showed the most cytotoxic agents. The correlation between skin irritation and cytotoxicity ($IC_{50}$/ at different time point was 0.814, 0.757, 0.814 and 0.7 at 3, 24, 48 and 72 h, respectively. We also fecund that IC$_{20}$ and IC$_{80}$ of these agents showed similar correlation with skin irritation. These results therefore demonstrated that there is close correlation between skin irritation and cytotoxicity $IC_{50}$/ value by MTT in HaCaT cell at early time points by anti-wrinkle agents or IC$_{20}$ value. $IC_{50}$/ at earily time point or IC$_{20}$ values may be reliable alternative determinant of skin irritation.n.

• 한국통신학회논문지
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• 제25권9B호
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• pp.1570-1578
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• 2000

본 논문은 채널간의 간섭을 줄이는 관점에서 코사인 변조 필터 뱅크와 사인 변조 필터 뱅크로 이루어진 필터뱅크의 쌍을 다중 반송파 부호 분할 다원 접속(multi-carrier code division multiple access: MC-CDMA) 시스템의 다중화 전송에 적용하였다. 웨이브렛 특성을 필터 뱅크의 구현에 활용하는 제안된 기법은 이산 퓨리에 변환(discrete Fourier transform: DFT)에 기반을 둔 기존의 MC-CDMA 시스템과 비교하였을 때, 전송 채널의 부채널화의 우수성으로 인해 채널간의 간섭을 감소시킬 수 있다. 제안된 직교 쌍 필터 뱅크를 기반으로 하는 MC-CDMA 시스템의 성능을 평가하기 위하여, 레이라이 페이딩 채널과 가우시안 잡음 채널에서 역 방향 링크의 신호 대 잡음비에 대한 비트 오율을 계산한다. 성능평가 결과는 제안한 시스템이 간섭의 영향을 최소화하는 측면에서 기존의 MC-CDMA 시스템 보다 우수한 성능을 보이고 있다.

• 한국실내디자인학회:학술대회논문집
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• 한국실내디자인학회 2008년도 춘계학술발표대회 논문집
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• pp.71-73
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• 2008

In early Highlighting the client's personality especially, home design demands very careful consideration. It's not an easy task to understand the characteristics of each family member, to take into account their requirements, and strike proper harmony among them. For this Sampung Apartment Project, I decided to create a cozy homelike atmosphere by using overall modern and antique furniture, props, and lighting. I tried a different sense of space by choosing wood as the main material, installing furniture that looked antique, and applying painting with touch instead of pictures or wallpaper By the use of the light bulb color overall, lighting was yellow and added more comfort. Local lighting was used in certain places to add more fun along with the props. After choosing white as the main color, point colors were determined according to the client's inclination toward green and blue. The color choice also matched the client's paintings that were in soft green and blue. Each room was planned and color coordinated according to their own characteristics. The children's rooms were planned with such point colors as pink, green, and blue. The master bedroom and the family room were produced around gold and grey color, respectively.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2011년도 추계학술발표대회
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• pp.733-734
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• 2011

지난 몇 년 동안 무선랜(Wireless LAN)은 다양한 영역에서 가장 널리 사용 되었으며, 가장 크게 발전을 하였다. 그러나 무선랜의 특성상 해킹과 침투에 취약한 약점을 안고 있다. 아직도 많은 보안적 취약점을 가지고 있으며, 특히 그 중에서도 Rogue AP(Access Point)는 가장 심각한 보안 취약점으로 대두되고 있다. 현재 Rogue AP 탐지를 위하여 넷스텀블러와 같은 스니핑 소프트웨어를 설치하여 주변 지역을 돌아다니는 워드라이빙 형태의 탐지방법은 아직도 사용되고 있다. 그러나, 이러한 방법은 대규모로 확장되어 가는 무선랜 환경에 적합하지 않다. 본 논문은 무선랜 환경에서 Rogue AP 탐지 문제의 해결책을 제시한다. AP의 전파 영역을 이용하는 방식으로, AP가 신호를 받을 수 있도록 수정하여, 주변에 새로운 AP가 탐지될 경우, AP가 서버와 새롭게 발견된 AP에 신호를 보내고, 이를 바탕으로 서버는 WhiteList를 통해서 Rogue AP 여부를 결정한다. 따라서 본 논문의 제안 방식은 기존의 탐지 방식에 비해 Rogue AP의 효과적 탐지가 가능하다.

• Journal of Veterinary Science
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• 제24권6호
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• pp.79.1-79.16
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• 2023

Background: The need for a storage method capable of preserving the intrinsic properties of bones without using toxic substances has always been raised. Supercooling is a relatively recently introduced preservation method that meets this need. Supercooling refers to the phenomenon of liquid in which the temperature drops below its freezing point without solidifying or crystallizing. Objectives: The purpose of this study was to identify the preservation efficiency and applicability of the supercooling technique as a cortical bone allograft storage modality. Methods: The biomechanical effects of various storage methods, including deep freezing, cryopreservation, lyophilization, glycerol preservation, and supercooling, were evaluated with the three-point banding test, axial compression test, and electron microscopy. Additionally, cortical bone allografts were applied to the radial bone defect in New Zealand White rabbits to determine the biological effects. The degree of bone union was assessed with postoperative clinical signs, radiography, micro-computed tomography, and biomechanical analysis. Results: The biomechanical properties of cortical bone grafts preserved using glycerol and supercooling method were found to be comparable to those of normal bone while also significantly stronger than deep-frozen, cryopreserved, and lyophilized bone grafts. Preclinical research performed in rabbit radial defect models revealed that supercooled and glycerol-preserved bone allografts exhibited significantly better bone union than other groups. Conclusions: Considering the biomechanical and biological superiority, the supercooling technique could be one of the optimal preservation methods for cortical bone allografts. This study will form the basis for a novel application of supercooling as a bone material preservation technique.

• International journal of advanced smart convergence
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• 제12권4호
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• pp.306-313
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• 2023

Having pet is one of the activities people living in modern society do to relieve stress and find peace of mind. Currently, the object of companion animals has moved beyond being a real 'living entity' and has developed to a stage where the animal's upbringing process can be enjoyed in a virtual space by being programmed in digital content. This paper studies detailed elements such as character design, interaction, and realism of 'Tamagotchi (1996)', which can be said to be the beginning of digital training content, and 'Peridot (2023)', a recently introduced augmented reality-based training content. The point was that it was training content using portable electronic devices. However, while the environment in the electronic device in which Tamagotchi's character exists was a simple black and white screen, the environment in which Peridot's character operates has been changed to the real world projected on the screen based on augmented reality. Mutual communication with characters in Tamagotchi remained a response to pressing buttons, but in Peridot, it has advanced to the point where you can pet the characters by touching the smartphone screen. In addition, through object and step recognition, it was confirmed that the sense of reality had become more realistic, with toys thrown by users on the screen bouncing off real objects. We hope that this research material will serve as a useful reference for the development of digital training content to be developed in the near future.

• 한국식품영양과학회지
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• 제37권5호
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• pp.640-646
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• 2008

쌀겨와 발효쌀겨, 쌀겨유의 쇼트닝 대체에 따른 제빵특성 변화에 대하여 조사하였다. 빵 반죽에 대한 쌀겨의 첨가는 제빵 후 명도의 감소, 황색도 및 적색도의 증가와 전반적 물성 변화를 가져오나, 5% 정도의 쌀겨 첨가는 쌀겨의 기능성을 가지면서 대조구와 외관 및 물성적으로 큰 차이를 보이지 않았다. 효모로 예비 발효한 발효쌀겨의 첨가는 대조구와 큰 차이를 보이지 않으면서 texture 및 풍미가 향상되었다. 빵 반죽에 대한 쌀겨유의 쇼트닝 대체는 첨가 수준이 클수록 반죽 내 비 용적이 감소되었다. 황색의 쌀겨유의 첨가는 반죽의 명도를 낮추고 황색도를 증가시켰다. 또한 쇼트닝의 쌀겨유 대체는 경도, 씹힘성 그리고 부서짐 등의 증가를 가져오는 불리한 점이 있으나, 50% 정도의 쌀겨유 대체는 빵의 물성변화에 있어 대조구와 큰 차이를 나타내지 않았다. 또한 쌀겨유의 대체는 관능평가에서 부피의 상대적 감소 및 경도의 증가로 인한 질감의 저하를 가져오나, 제빵 후 풍미 향상을 유도하는 것으로 나타났다. 이상의 결과로 볼 때 쌀겨, 발효쌀겨 그리고 쌀겨유의 제빵과정 중 첨가는 빵의 색, 부피 등 외관상 대조구에 비하여 다소 변화를 가져올 수 있으나, 쌀겨 특히, 발효쌀겨의 첨가는 오히려 맛 과 풍미 향상을 가져오는 것으로 사료된다.

• Journal of Biosystems Engineering
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• 제39권2호
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• pp.87-95
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• 2014

Purpose: The purpose of this study was to design a variable frequency LED light system for plant factory which combined red, blue, green, white, and UV lights and controlled the ratio of the light wavelength. In addition, this study evaluated the performance of each combination of LED to verify the applicability. Methods: Four combinations of LED (i.e. Red+Blue, Red+Blue+Green, Red+Blue+White, Red+Blue+UV) were designed using five types of LED. The system was designed to control the duty ratio of each wavelength of LED by 1% interval from 0~100%, the pulse by 1Hz interval from 1~20kHz. Response characteristics of the control system, spectral distribution of each combination, light uniformity and uniformity ratio were measured to test the performance of the system. Results: Clean waveforms were measured from 10Hz to 10kHz regardless of duty ratio. Frequency distortion was observed within 5% of inflection point at frequencies above 10kHz regardless of duty ratio, but it was judged negligible. Spectra showed a normal distribution, and maximum PPF with duty ratio of 100% was $271.4{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ for the Red+Blue combination. PPF of the Red+Blue+Green combination was $258.9{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, and that of the Red+Blue+White combination was $273.9{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$. PPF of the Red+Blue+UV combination was $267.7{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$. Uniformity ratio for the area excepting border showed 0.90 for the Red+Blue and Red+Blue+White combinations, 0.87 for the Red+Blue+Green combination, and 0.88 for the Red+Blue+UV combination. The light was irradiated evenly at the area excepting border, so it was suitable for plant growing. Conclusions: From the results of this study, response characteristics of the control system, spectral distribution of each combination, light uniformity and uniformity ratio were suitable for applying into the plant factory.