• 펄프종이기술
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• 제31권2호
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• pp.70-76
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• 1999

This study was to measure the potential of nonwoody fibrous material, kenaf. Whole stalk of kenaf, Hibiscus cannabinus was separated by two parts of bast and core portion, and cooked separately by alkaline method. Morphological characteristic was evaluated using confocal laser scanning microscope (CLSM) and fiber quality analyzer(FQA). The strength properties of handsheets, made by different mixing ration between kenaf base and core fibers, were measured. Cross-sectional area of bast fibers was smaller than that of core fibers, but the bast fibers had a thick cell wall and narrow lumen area. Bast fibers were longer in length than core fibers. Core fibers had thin cell walls, broad lumen areas, and short lengths, and they had collapsed shape even in water. These characteristics of core fibers affected strength properties of handsheet positively. When the amount of core fibers increased, the strength properties of handsheet were increased. When the amount of bast fibers increased, the handsheet had rougher surface and higher air permeability.

• Asian-Australasian Journal of Animal Sciences
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• 제15권10호
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• pp.1502-1506
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• 2002

This experiment was conducted to evaluate the effects of the broiler's genotype ($G_t$) and ambient temperature ($T_a$) on performance and core body temperature ($T_core$) of broiler chicks. A factorial arrangement of two $G_t$ (Hubbard and ISA J57 chicks) and two $T_a$ (moderate, $23{\pm}0.5^{\circ}C$ and hot, $33{\pm}0.5^{\circ}C$) were used in this study. Performance data (body weight gain, feed intake and feed:gain ratio) were determined weekly for six weeks. Chicks' $T_core$ was measured using a biotelemetric system between Weeks five and six. Results showed that body weight gain and feed intake were significantly high, and feed:gain ratio was significantly low for Hubbard chicks compared to those of ISA J57 chicks. High $T_a$ significantly reduced weight gain and feed intake. Furthermore, the reduction in body weight gain and feed intake under the hot $T_a$ was more pronounced for Hubbard chicks than those of the ISA J57 chicks resulting in significant $G_t$ by $T_a$ interaction. Chicks grown under moderate $T_a$ had significantly lower $T_core$ than those grown under hot $T_a$. The $T_core$ of the Hubbard chicks was significantly lower than that of the ISA J57 at the moderate $T_a$ while under the hot $T_a$, the magnitude of the change in $T_core$ was more pronounced in Hubbard chicks than that of ISA J57; this resulted in a significant $G_t$ by $T_a$ interaction. The results of this study indicate that chicks with higher potential for growth under thermo-neutral temperature are more susceptible to heat stress than chicks with lower potential for growth. This maybe due, at least in part, to their lower body $T_core$ under moderate temperature and to the lesser ability of these fast growing chicks to regulate their $T_core$ when exposed to heat stress, as was clearly shown on these birds' performance.

• Nuclear Engineering and Technology
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• 제37권1호
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• pp.91-100
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• 2005

Kyung-hee Thorium Fuel (KTF), a heterogeneous thorium-based seed and blanket design concept for pressurized light water reactors, is being studied as an alternative to enhance proliferation resistance and fuel cycle economics of PWRs. The proliferation resistance characteristics of the KTF assembly design were evaluated through parametric studies using neutronic performance indices such as Bare Critical Mass (BCM), Spontaneous Neutron Source rate (SNS), Thermal Generation rate (TG), and Radio-Toxicity. Also, Fissile Economic Index (FEI), a new index for gauging fuel cycle economy, was suggested and applied to optimize the KTF design. A core loaded with optimized KTF assemblies with a seed-to-blanket ratio of 1: 1 was tested at the Korea Next Generation Reactor (KNGR), ARP-1400. Core design characteristics for cycle length, power distribution, and power peaking were evaluated by HELIOS and MASTER code systems for nine reload cycles. The core calculation results show that the KTF assembly design has nearly the same neutronic performance as those of a conventional $UO_2$ fuel assembly. However, the power peaking factor is relatively higher than that of conventional PWRs as the maximum Fq is 2.69 at the M$9^{th}$ equilibrium cycle while the design limit is 2.58. In order to assess the economic potential of a heterogeneous thorium fuel core, the front-end fuel cycle costs as well as the spent fuel disposal costs were compared with those of a reference PWR fueled with $UO_2$. In the case of comprising back-end fuel cycle cost, the fuel cycle cost of APR-1400 with a KTF assembly is 4.99 mills/KWe-yr, which is lower than that (5.23 mills/KWe-yr) of a conventional PWR. Proliferation resistance potential, BCM, SNS, and TG of a heterogeneous thorium-fueled core are much higher than those of the $UO_2$ core. The once-through fuel cycle application of heterogeneous thorium fuel assemblies demonstrated good competitiveness relative to $UO_2$ in terms of economics.

• 설비공학논문집
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• 제10권2호
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• pp.193-201
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• 1998

A heat exchanging system employing the impinging air jet is still widely used In the various fields due to its inherent merits that include the easiness in engineering applications and the high heat and/or mass transfer characteristics. The purpose of this study is to investigate the enhancement of heat transfer and flow characteristics by placing a turbulence promoters in front of heat exchanging surface. In this study, a series of circular rods are placed at the upstream of a flat plate heat exchanger that is located at potential core region(H/W=2) of a two-dimensional impinging air jet. Heat transfer enhancement is achieved by inserting turbulence promoter that results in the flow acceleration and disturbance of boundary layer. The average Nusselt number of the flat plate with the turbulence promoters is found to be around 1.42 times higher than that of the flat plate without the turbulence promoters. Based on the results of flow visualization with a smoke wire, it is confirmed that the heat transfer enhancement is caused by the flow separation and disturbance of boundary layer by inserting the turbulence promoter.

• 물과 미래
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• 제27권2호
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• pp.121-128
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• 1994

단락부에서의 모형실험을 통하여 표면 유속의 감소경향, 낙하리영역의 길이, 잠재핵(potential core)의 길이 등을 고찰하여 단구 전면에 대한 흐름을 규명하였다. 흐름속에 부류사가 혼재되어 있는 경우, 부유사가 낙하리영역 중에 퇴적하게 되어 단구의 진행 속도에 영향을 주게되므로 이를 규명하기 위하여 단락부에 있어서 부류사의 유입에 대한 실험을 실시하고, 이에 대한 식을 유도하여 실험 결과로부터 이들 식의 유효성을 증명하였다. 또한 단락부의 낙하리영역에서 사이폰에 의하여 채취되는 부류사량에 대한 실험 결과,$q_{s0}$ 를 규정하는 파라메타에 관한 검토를 실시하여 부류사의 퇴적 특성을 설명하였다.

• 농촌계획
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• 제23권3호
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• pp.1-12
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• 2017

The purpose of this study is to reveal network potential among agricultural villages focused on landscape and amenity resources. For this study, we conducted Social Network Analysis (SNA) utilizing existing landscape resource database. As a result of the study, major landscape types shared among villages were found for each city. For example, agricultural and residential landscapes were identified as major types for Danjin city. Add to major landscape resources, in Dangjin city, Habduk village were recognized as a core. Seokmun, Daehoji, Woogang, and Sunseong villages were widely found as the sub core group. For Seosan city, Jigok, Palbong, and Kobuk villages were widely recognized as core group. Most of villages which indicated the highest degree centrality were superior in terms of the number of total landscape resources as well as landscape type diversity. These results can be useful for initial planning process when considering major theme for landscape-based network organization. Also, this information will be helpful for planning stage through the specification of the potential role of each village in overall network.

• The Plant Pathology Journal
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• 제29권2호
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• pp.144-153
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• 2013

Diverse bacteria are known to colonize plants. However, only a small fraction of that diversity has been evaluated for their biopesticide potential. To date, the criteria for sampling and selection in such bioprospecting endeavors have not been systematically evaluated in terms of the relative amount of diversity they provide for analysis. The present study aimed to enhance the success of bioprospecting efforts by increasing the diversity while removing the genotypic redundancy often present in large collections of bacteria. We developed a multivariate sampling and marker-based selection strategy that significantly increase the diversity of bacteria recovered from plants. In doing so, we quantified the effects of varying sampling intensity, media composition, incubation conditions, plant species, and soil source on the diversity of recovered isolates. Subsequent sequencing and high-throughput phenotypic analyses of a small fraction of the collected isolates revealed that this approach led to the recovery of over a dozen rare and, to date, poorly characterized genera of plant-associated bacteria with significant biopesticide activities. Overall, the sampling and selection approach described led to an approximately 5-fold improvement in efficiency and the recovery of several novel strains of bacteria with significant biopesticide potential.

• 대한임베디드공학회논문지
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• 제8권2호
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• pp.87-93
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• 2013

In this paper, we implemented and evaluated the performance of a vector-based rasterization algorithm of 3D graphics using a SIMD-based many-core processor that consists of 4,096 processing elements. In addition, we compared the performance and efficiency of the rasterization algorithm using the many-core processor and commercial GPU (Graphics Processing Unit) system which consists of 7 GPUs and each of which have 512 cores. Experimental results showed that the SIMD-based many-core processor outperforms the commercial GPU system in terms of execution time (3.13x speedup), energy efficiency (17.5x better), and area efficiency (13.3x better). These results demonstrate that the SIMD-based many-core processor has potential as an embedded mobile processor.

• BMB Reports
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• 제48권12호
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• pp.643-644
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• 2015

In eukaryotes, small RNAs play important roles in both gene regulation and resistance to viral infection. Argonaute proteins have been identified as a key component of the effector complexes of various RNA-silencing pathways, but the mechanistic roles of Argonaute proteins in these pathways are not clearly understood. To address this question, we performed single-molecule fluorescence experiments using an RNA-induced silencing complex (core-RISC) composed of a small RNA and human Argonaute 2. We found that target binding of core-RISC starts at the seed region of the guide RNA. After target binding, four distinct reactions followed: target cleavage, transient binding, stable binding, and Argonaute unloading. Target cleavage required extensive sequence complementarity and accelerated core-RISC dissociation for recycling. In contrast, the stable binding of core-RISC to target RNAs required seed-match only, suggesting a potential explanation for the seed-match rule of microRNA (miRNA) target selection.

• Molecules and Cells
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• 제44권12호
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• pp.883-892
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• 2021

Genome-wide chromosome conformation capture (3C)-based high-throughput sequencing (Hi-C) has enabled identification of genome-wide chromatin loops. Because the Hi-C map with restriction fragment resolution is intrinsically associated with sparsity and stochastic noise, Hi-C data are usually binned at particular intervals; however, the binning method has limited reliability, especially at high resolution. Here, we describe a new method called HiCORE, which provides simple pipelines and algorithms to overcome the limitations of single-layered binning and predict core chromatin regions with three-dimensional physical interactions. In this approach, multiple layers of binning with slightly shifted genome coverage are generated, and interacting bins at each layer are integrated to infer narrower regions of chromatin interactions. HiCORE predicts chromatin looping regions with higher resolution, both in human and Arabidopsis genomes, and contributes to the identification of the precise positions of potential genomic elements in an unbiased manner.