• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2020년도 추계학술발표대회
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• pp.182-185
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• 2020

특정 통신 프로토콜을 지원하는 물리 계층 트랜시버(PHY)가 없을 때 물리 계층의 부재로 인해 해당 프로토콜이 사용된 통신 시스템을 구현할 수 없다. 그래서 PHY 의 부재는 프로토콜 연구에 큰 걸림돌이 된다. 이런 경우 FPGA 로 물리 계층을 구현할 수 있다. FPGA 를 사용하면 목적과 상황에 맞춰 물리 계층을 구현할 수 있다는 장점이 있다. 통신 속도, 채널의 개수, 오류 검출 알고리즘 등 프로토콜의 다양한 요소를 사용자의 마음대로 구현할 수 있다. 본 논문에는 10Mbps 이더넷 통신에 대한 물리 계층을 FPGA 로 구현하는 실험을 담고 있다. 결과적으로 물리 계층의 구현에 성공했지만 검증에는 실패하였다. 실험에 사용된 보드에는 이더넷 PHY 가 장착되어 있었다. 이더넷 PHY 가 수신 신호를 간섭해서 물리 계층의 동작성을 검증할 수 없었다. 추후에 이더넷 PHY 를 제거하고 재실험을 진행할 것이다. 비록 검증에는 실패했지만, 실험을 통해 FPGA 로 물리 계층을 구현할 수 있음을 보이고 통신 프로토콜 연구 방법으로 이를 제안하고자 한다.

• Asian-Australasian Journal of Animal Sciences
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• 제29권10호
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• pp.1483-1489
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• 2016

Most of amino acid (AA) digestibility values for feed ingredients are obtained using pigs cannulated in the distal ileum. The ileal-cannulated pig model uses pigs older than six weeks due to difficulties related to implanting the T-cannula in distal ileum of younger pigs and complications during the post-surgical recovery. However, to properly formulate the diet of weaned pigs, the nutritive value of feed ingredients should be determined with younger pigs. Thus, 25 weaned pigs were used to determine the apparent total tract digestibility (ATTD) of nutrients, energy, and apparent ileal digestibility (AID) and standardized ileal digestibility (SID) ileal AA digestibility of broken rice (BR), with or without multicarbohydrase (MC) and phytase (Phy) supplementation. Piglets were weaned at 23 d of age and individually housed in digestibility cages until 45 d of age. The trial consisted of 7 d of adaptation to the experimental diets and 3 d of excreta (feces and urine) collection. Ileal digesta was collected at slaughter (about 6 weeks of age). A completely randomized experimental design was used to determine the effects of MC and Phy. Reference diets (RD, 5% casein) was replaced by 30% of BR with or without MC, Phy, or MC+Phy. The RD was used to quantify endogenous AA losses. BR with Phy supplied had increased the ATTD of dry matter (p<0.05) and SID of histidine (p = 0.05), arginine, leucine, lysine, valine, alanine, and proline (p<0.05). BR with MC had been increased digestible energy and protein and SID for histidine (p<0.05). There was no interaction between Phy and MC on the BR nutrient digestibilities. Standardized amino acid digestibilities of BR, without enzymes, were lower than those values reported in the literature. The MC and Phy improved the digestibility of some nutrients and energy of BR in post-weaned piglet diets.

• 한국광학회:학술대회논문집
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• 한국광학회 2007년도 하계학술발표회 논문집
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• pp.1-1
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• 2007

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제24권4호
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• pp.346-356
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• 2021

Purpose: Campylobacter species are currently the most common cause of bacterial gastroenteritis. In Lebanon, Campylobacter infection occurrence is underdiagnosed owing to the lack of specific culture and rapid test kits, particularly among children. This study aimed to evaluate the prevalence, laboratory findings, and clinical characteristics of Campylobacter infection in hospitalized children with acute gastroenteritis in South Lebanon. Methods: We conducted a 6-month retrospective cohort study between January and June 2018, including 291 children aged between 1 month and 12 years, who were admitted to a tertiary healthcare center in South Lebanon. The medical files of the patients were reviewed to retrieve the required clinical information, including clinical and laboratory data. Results: The prevalence of campylobacteriosis agents in pediatric patients with acute gastroenteritis is 12.02%. Patients infected with Campylobacter had more severe acute gastroenteritis than Campylobacter-negative patients and often presented with high-grade fever, diarrhea episodes more than six times per day, diarrhea lasting for more than five days, and dehydration. Indeed, children with high-grade fever (≥38.5℃) were five times more likely to test positive for Campylobacter than those with low-grade fever. In addition, the results showed a higher Vesikari score for the majority of Campylobacter-positive patients with severe acute gastroenteritis compared to a moderate profile for Campylobacter-negative patients. Conclusion: The present study findings highlight that Campylobacter infection is frequent among children with acute gastroenteritis. Therefore, the detection of Campylobacter should be carried out for the diagnosis of human gastroenteritis in Lebanon, along with the detection of routine enteropathogens.

• Asian-Australasian Journal of Animal Sciences
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• 제27권7호
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• pp.1003-1012
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• 2014

The use of a suitable methodology to quantify the phytate phosphorus ($P_{phy}$) content in both the feed and the excreta from broilers is required to enable accurate calculation of the catalytic efficiency of the phytase supplemented in the feed. This study was conducted to compare 2 analytical methodologies (colorimetry and also high-performance liquid chromatography with a refractive index detector) in order to calculate the phytase efficiency by utilizing the results from the methodology that was shown to be the most appropriate. One hundred and twenty broilers were distributed in a $(4+1){\times}2$ factorial arrangement, corresponding to 4 diets that were equally deficient in P supplemented with increasing levels of phytase (0, 750, 1,500, and 2,250 units of phytase activity - FTU - per kg of feed) plus 1 positive control diet without phytase, supplied to male and female birds. The result indicated that the colorimetric methodology with an extraction ratio of 1:20 (mass of sample in g:volume of the solvent extractor in mL) was shown to be the most adequate. There was no interaction between the phytase level and the sex of the broilers (p>0.05). Males consumed 12% more $P_{phy}$ than did females (p<0.01), but the sex of the broilers did not affect (p>0.05) the excretion and retention coefficient of $P_{phy}$. The increase in the phytase level of the diet reduced (linear, p<0.01) the $P_{phy}$ excretion. The greatest $P_{phy}$ retention was estimated at 87.85% when the diet contained 1,950 FTU/kg (p<0.01), indicating that it is possible to reduce the inorganic P in the formulation at an amount equivalent to 87.85% of the $P_{phy}$ content present in the feed, which, in this research, corresponds to a decrease in 2.86 g of P/kg of the feed.

• 한국작물학회지
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• 제43권2호
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• pp.71-76
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• 1998

To define the relations between endogenous GA levels and growth and flowering in short-day plant sorghum, growth retardant BX-112 was applied to two sorghum genotypes, wild-type and phytochrome B mutant (phyB-1), which grows faster and flowers earlier than the wild-type. BX-112 and $GA_3$ were applied as a soil drench, and plant height, culm length, and date to floral initiation were investigated. Endogenous GAs contents were measured with GC-MS-SIM. BX-112 treatments inhibited shoot growth in both genotypes and drastically reduced $GA_1$ and $GA_8$ levels. With increasing BX-112 concentrations, $GA_1$ concentrations declined linearly, but caused the accumulation of intermediates from $GA_12$ to $GA_20$. This result implies that $GA_1$ is the major active endogenous GA in shoot elongation in a short day plant sorghum. The inhibition of plant growth in both of wild type and phyB-1 by BX-112 was very similar, while BX-112 effects on floral initiation in two types of plants differed significantly. Floral initiation of phyB-1 was not affected by BX-1l2, but that of wild-type was delayed as BX-1l2 concentration increased. Because BX-112 treatment causes accumulation of biosynthetic intermediates between synthetic pathway from $GA_12$ to $GA_20$ and because phyB-1 is altered in GA metabolism in this same region of the early C13-hydroxylation pathway, BX-112 may fail to block flowering of phyB-1.

• Molecules and Cells
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• 제43권7호
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• pp.645-661
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• 2020

Leaf senescence is a developmental process by which a plant actively remobilizes nutrients from aged and photosynthetically inefficient leaves to young growing ones by disassembling organelles and degrading macromolecules. Senescence is accelerated by age and environmental stresses such as prolonged darkness. Phytochrome B (phyB) inhibits leaf senescence by inhibiting phytochrome-interacting factor 4 (PIF4) and PIF5 in prolonged darkness. However, it remains unknown whether phyB mediates the temperature signal that regulates leaf senescence. We found the light-activated form of phyB (Pfr) remains active at least four days after a transfer to darkness at 20℃ but is inactivated more rapidly at 28℃. This faster inactivation of Pfr further increases PIF4 protein levels at the higher ambient temperature. In addition, PIF4 mRNA levels rise faster after the transfer to darkness at high ambient temperature via a mechanism that depends on ELF3 but not phyB. Increased PIF4 protein then binds to the ORE1 promoter and activates its expression together with ABA and ethylene signaling, accelerating leaf senescence at high ambient temperature. Our results support a role for the phy-PIF signaling module in integrating not only light signaling but also temperature signaling in the regulation of leaf senescence.

• 한국통신학회논문지
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• 제32권6B호
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• pp.316-324
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• 2007

In this paper we proposed an energy consumption model for IR-UWB wireless sensor networks. The model takes the advantages of PHY-MAC cross layer design, and we used slotted and un-slotted sleeping protocols to compare the energy consumption. We addressed different system design issues that are responsible to energy consumption and proposed an optimum model for the system design. We expect the slotted sleeping will consume less energy for bursty load than that of the un-slotted one. But if we consider latency, the un-slotted sleeping model performs better than the slotted sleeping case.

• 전자통신동향분석
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• 제37권3호
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• pp.1-10
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• 2022

Traditional centralized radio access network architecture used for 4G is based on Option 8, a functional split between PHY and RF. This option is commonly used with a fronthaul interface based on common public radio interface (CPRI) specifications; however, the increased data rates in 5G make this option impractical because of the fronthaul interface's high bandwidth requirement. Since CPRI specifications have many vendor-specific options, achieving multi-vendor interoperability becomes challenging. Open RAN (O-RAN) Alliance is developing novel open fronthaul interface specifications based on the functional split Option 7-2x, one of the intra-PHY split options, to relax the bandwidth requirement of the fronthaul interface and achieve multi-vendor interoperability. This article provides a brief overview of the various functional split options for 5G fronthaul that have been reported so far and existing fronthaul technologies. Further, the technological trends in the 5G open fronthaul interface is discussed, focusing on the O-RAN Alliance specifications under standardization.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2011년도 춘계학술발표대회
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• pp.756-759
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• 2011

산업장 기반 모니터링 시스템에 무선 네트워크 기술의 도입은 시스템 도입 및 유지보수에 있어 반드시 필요하다. 무선 네트워크 기반의 산업장 모니터링을 위해 현재 USN 네트워크에서 광범위하게 사용되고 있는 IEEE 802.15.4 하드웨어 및 MAC 을 이용하여 Freequency Hopping을 수행하는 Superframe 기반의 TDMA 기술을 구현하였다.