• 한국통신학회논문지
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• 제35권1A호
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• pp.16-24
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• 2010

HSUPA(High Speed Uplink Packet Access)는 고속 스케줄링, HARQ, 짧은TTI등을 Node B에서 제공함으로써 HSDPA 에 대응되게 상향링크 쪽의 고속 데이터 전송률을 제공하는 WCDMA의 Rel 6 이동통신 기술이다. WCDMA 시스템의 RNC(Radio Network Controller)와 기지국인 Node B 간의 Iub 구간에서 혼잡을 검출하는 것은 사용자의 통신서비스 품질을 높이기 위해서 매우 중요하다. 이를 위해 TNL 혼잡 검출과 Node B의 링크 버퍼 관찰 방법을 제안하고 이를 통해 얻을 수 있는 패킷 수율에 대해 성능 분석을 하였다. 제안하는 방법을 통해 좁은 Iub 대역폭의 혼잡 검출은 패킷 수율 향상에 도움이 되는 것을 확인할 수 있었다.

• 콘크리트학회지
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• 제3권3호
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• pp.129-139
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• 1991

본 논문에서는 철근콘크리트 부재에 강섬유를 혼입하였을때의 역학적 겅동에 관하여 이론 및 실험적 연구를 수행하였다. 이를 위하여 포괄적인 실험연구를 수행하였으며, 단철근 콘크리트 보와 복철근 콘크리트 보에 대하여 강섬유의 혼입효과를 규명하였다. 본 실험으로부터 하중-처짐관계, 균열폭, 균열간격, 균열형상, 철근 및 콘크리트 변형도를 측정하였다. 실험결과 강섬유의 혼입으로 인하여 균열이 크게 역제되고 균열폭이 크게 감소함을 발견하였다. 또한, 부재의 연성과 극한저항모멘트가 크게증가하였다. 본 논문에서는 이러한 강섬유의 혼입효과를 설명할 수 있는 이론모델을 유도하여 제시하였으며, 앞으로 강섬유콘크리트는 연성을 필요로하는 내진구조물등에 효율적으로 이용할 수 있을 것으로 사료된다.

• 디지털산업정보학회논문지
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• 제13권2호
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• pp.35-42
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• 2017

The TDD LTE MU-MIMO HARQ system is designed and implemented using GPU based on 3GPP Rel.10 standard. The system consists of the DU part of the base station and the terminal using the general computer based on the GeForce GTX TITAN graphics card provided by NIVIDIA, and constructed the part of the RU using USRP N210 provided by Ettus. In the implementation part, SDR standard is applied, so that various communication standards can be compatible with software. The retransmission is implemented by combining the previous data with the retransmission data using Chase Combining among HARQ methods. In order to confirm that the retransmission was successful, the performance evaluation used LLR constellation. First, if there is an error in the data, the LLR value is not distributed at the corresponding position. in this case, a retransmission is performed to chase combine the previously stored error data and retransmitted data. As a result, the LLR value was distributed at the position of the corresponding LLR value per bit. Through this, it can be confirmed that error - free data is formed by using Chase Combining after retransmission.

• International Journal of Oral Biology
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• 제46권1호
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• pp.51-59
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• 2021

Periodontal disease is an inflammatory disease that affects the destruction of the bone supporting the tooth and connective tissues surrounding it. Periodontal ligament fibroblasts (PDLFs) induce overexpression of matrix metalloproteinase (MMP) involved in periodontal disease's inflammatory destruction. Osteoclasts take part in physiological bone remodeling, but they are also involved in bone destruction in many kinds of bone diseases, including osteoporosis and periodontal disease. This study examined the effect of baicalin on proteolytic enzymes' production and secretion of inflammatory cytokines in PDLFs and RAW 264.7 cells under the lipopolysaccharide (LPS)-induced inflammatory conditions. Baicalin inhibited the expression of the protein, MMP-1 and MMP-2, without affecting PDLFs' cell viability, suggesting its possibility because of the inhibition of phosphorylation activation of mitogen-activated protein kinase's p38, and the signal transduction process of nuclear factor κB (NFκB)-related protein. Also, baicalin reduced the expression of MMP-8 and MMP-9 in RAW 264.7 cells. This reduction is thought to be due to the inhibition of the signal transduction process of NFκB-related proteins affected by inhibiting p65RelA phosphorylation. Also, baicalin inhibited the secretion of nitric oxide and interleukin-6 induced by LPS in RAW 264.7 cells. These results suggest that baicalin inhibits connective tissue destruction in periodontal disease. The inhibition of periodontal tissue destruction may be a therapeutic strategy for treating inflammatory periodontal-diseased patients.

• 한국환경보건학회지
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• 제28권5호
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• pp.22-27
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• 2002

The composting practice has been recognized as the most popular way of controlling food waste and many attempt have been made in the field to establish more efficient and economical process. Some of the efforts are mixing cured compost with sawdust as alternative bulking agent, seeding commercially produced microorganism and/or combination of above. However, verification of such efforts is often restricted because of either the lack of engineering consideration on the limitation of composting facility scales. In this study, the effect of mixing materials in food waste composting was investigated by controlling the combination and the mixing ratio of them. When the cured compost was mixed with saw dust. the decomposition of organic material was proven to be more active by observing the compost temperature, the oxygen (O$_2$) consumption, and the cumulative carbon dioxide ($CO_2$) profile. However, the quantity of compost mix-ing seemed not to influence the reaction as long as the minimum required amount was mixed. The feeding of com-mercially produced microorganism had a tendency to prolong the thermophilic stage, which helped to increase the decomposition but it resulted in composting period. Regardless of the composting condition, bacteria and actinomycetes increased in population as the reaction approached to the end. The population of bacteria and actinomycetes were rel-atively higher than those of fungi and yeast throughout the reaction.

• 한국환경보건학회:학술대회논문집
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• 한국환경보건학회 2005년도 국제학술대회
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• pp.326-329
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• 2005

A worker who grinded the inner parts of camshafts for automobile engines using water-soluble metalworking fluid (MWF) for 14 years was diagnosed with sinusitis. We postulated that the outbreak of sinusitis could be associated with exposure to microbes contaminated in water-soluble MWF during the grinding operation. To suggest responsible agents for this outbreak, quantitative exposure assessment for chemical and biological agents and prevalence of work-related respiratory symptoms by questionnaire were studied. The exposure ranges of MWF mist (0.59 $mg/m^3$to 2.12 $mg/m^3$) measured during grinding exceeded 0.5 $mg/m^3$ of the recommended exposure limit (REL). Grinder's exposures to bacteria, fungi and endotoxins were also generally higher than not only the proposed standards, but also those reported by several studies to identify the cause of respiratory effects. Statistical test indicated that the prevalence rate of reported symptoms related to nasal cavities showed no significant differences among the operations. Evaluation on grinding operation characteristics and quantitative exposure assessment indicated that repeated exposure to MWF mist including microbes contaminated from the use of water-soluble MWF may cause respiratory diseases like sinusitis or at least increase susceptibility to the development of sinusitis

• 한국실내디자인학회논문집
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• 제14권5호
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• pp.245-253
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• 2005

The purpose of this study is to analyze the relationship between the personality type and the residential evaluation & remodeling preference in interior finishes and floor layouts. The subjects of this investigation were collected through questionnaire from two hundred and twelve adult residents who live in Seoul, Korea. By using the rotated component matrix of varimax method & the one way anova method of spss for windows Rel. 11.0 in my former study, there are analyzed several significances in eight personality types; E(extraversion), I(introversion), S(sensing), N(intuition), T(thinking), F(feeling), J(judging) and P(perceiving) in MBTI (Myers Briggs Type Indicator). This study shows that actual floor plans, remodeling preference plans & interior finishes materials of each personality type was analyzed several significances by Chi-Square. As results, during consulting the client in the residential projects, personality test may take precedence over everything else, and then designer can consider it for hidden client needs in the residential interiors & remodelings. Designers might understand the nature of personality in order to design wisely for clients. This method will allow the designer & consultant to more fully understand clients' preference.

• 한국식품위생안전성학회지
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• 제8권2호
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• pp.23-32
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• 1993

Species of the genus Fusarium are worldwide in their distribution. They are saprophytes as soil inhabitants and parasites of cultivated plants. Some isolates of certain species car capable of producing mycotoxins. Mycotoxicoses, including moldy corn toxicosis, alimentary toxic aleukia, fusariotoxicosis, and rel mold disease are known to be associated with trichothecene-producing fungi. Historically severe epidemic of cereal scab occred in the southern part of Korea in 1963. The epidemic caused a social problem because of not only heavy economic losses but also mycotoxicoses to humans and farm animals. However the toxic principles were remained unknown until some publications in 1980's indicated that trichothecenes and zearalenone were major mycotoxins in Korea cereals contaminated with Fusarium moniliforme have been found to be associated with human and animal disease such as leukoencephalomalacia in horses, pulmonary edema in swine and esophageal cancer in humans. High concentrations of fumonisins have been detected in corn samples from high espohoageal cancer risk areas of South Africa and China. Thus fumonisins have been implicated in the etiolgy of human esophageal cancer in those high incidence countries. Recently increase of imported cereals from foreign countries demands to assess the safety of mycotoxins in Korea. The informations on the natural occurrence of mycotoxins are needed to solve the toxicological problems in humans and farm animals associated with the consumption of moldy cereals.

• Archives of Pharmacal Research
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• 제23권4호
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• pp.413-417
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• 2000

The effect of ischemia/reperfusion-induced neuronal damage on the memory impairment were investigated using active avoidance and Morris water maze tasks in Wistar rats. Focal ischemia was induced by 1 h occlusion of the right middle cerebral artery (MCA) of Wistar male rats. Reperfusion was induced by releasing the occlusion and restoring the blood circulation for 24 h. The acquisition and preservation memory tested by active avoidance showed a significant difference between the sham and ischemia/reperfusion group. The water maze acquisition performance was also significant difference between sham and ischemia/repefusion groups in both latency and moving distance. The infarction volume was increased by the ischemia/reperfusion. Furthermore, the cresyl violet staining of the ischemia/reperfusion brain showed severe neuronal damage (pyramidal cell loss) in the cortex in addition to the striatum lesion of brain. This study shows that pyramidal cell damage in the cortex lesion may be partially related to memorial disturbance in the ischemia/reperfusion brain injury.

• Journal of Microbiology and Biotechnology
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• 제24권3호
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• pp.401-407
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• 2014

Quorum sensing and the stringent response are well-known regulation systems for the expression of virulence genes in enterohemorrhagic Escherichia coli (EHEC). However, how these two systems interact is not well known. E. coli strains with mutations in two regulation systems, ${\Delta}luxS$ (ECM101) and ${\Delta}luxS{\Delta}relA{\Delta}spoT$ (ECM201), and the ${\Delta}luxS$ complement strain to ECM201 (ECM202) were created from EHEC O157:H7 EDL933 to investigate how the regulatory systems interact. The phenotypic changes of the mutant strains were characterized and compared with the wild type. The mutant strains exhibited no obvious growth defects, although acid resistance and cellular cytotoxicity were decreased significantly in all the mutant strains. Phenotypic characterization revealed that mutations in the stringent response system (ECM201 and ECM202) influenced the metabolic (defective utilization of arabinose and L-sorbose) and enzymatic activities (decreased trypsin activity, and increased ${\alpha}$-glucosidase activity). In contrast, the quorum sensing system mutant (ECM101) did not display these phenotypes. The motility of the quorum sensing system mutant (ECM101) was unchanged, but mutation in the stringent response system influenced the motility. Our results suggest that quorum sensing interacts with the stringent response regulation system.