• 제목/요약/키워드: BF

검색결과 911건 처리시간 0.025초

배드민턴 스트로크 동작에 따른 근활성도 차이 분석 (Analysis of Differences in Muscle Activity according to Badminton Stroke Movements)

  • 김휘태;김기홍;김병관;정환종
    • 문화기술의 융합
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    • 제9권2호
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    • pp.519-524
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    • 2023
  • 이 연구는 경기상황과 유사한 점프 동작이 포함된 배드민턴 기술 동작 시 근육의 활성도의 차이를 조사함으로써 효율적인 기술훈련을 위한 기초자료를 구성하기 위한 목적이다. 남자 배드민턴 선수 7명을 대상으로 하여 스매시, 드롭, 클리어 기술을 무선배정으로 실시하였으며, 3가지 기술 동작 시행 중 근전도를 측정하였다. 측정된 근전도는 RMS로 산출하였으며 일원분산분석을 실시하였다. 스매싱 동작의 근활성도는 부위에 따른 유의한 차이를 보이지 않았다. 드롭 동작에서 상지 근육 중 PM의 활성도는 BC, ECR보다 낮았으며, FCR의 활성도는 EC보다 낮았다. ECR의 활성도는 PM, FCR보다 높았다. 몸통 근육 중 ES의 활성도는 RF, GM보다 낮았다. 하지 근육 중 RF의 활성도는 ES, BF보다 높았다. 클리어 동작에서 상지 근육 중 TC의 활성도는 FCR보다 높았다. 몸통 근육 중 ES의 활성도는 BF보다 낮았다. 하지 근육 중 RF의 활성도는 BF보다 높았으며, BF의 활성도는 RF, GM보다 낮았다. GM의 활성도는 BF보다 높았다. 배드민턴 기술에 따른 근활성도는 FCR에서 스매시와 드롭 동작이 클리어 동작보다 높았으며, RA에서 클리어가 스매시, 드롭 동작보다 높았다. 종합하면, 배드민턴 경기 중 근육활동은 기술별 특성에 따라 다르게 나타나고 노쪽손목굽힘근은 스매시와 드롭, 배곧은근은 클리어 동작에 영향을 미칠 수 있을 것으로 사료된다.

Supercapacitor용 이온성 액체 전해질의 전기화학적 특성 (Electrochemical Characteristics of Supercapacitor Using Ionic Liquid Electrolyte)

  • 김상길;황갑진;김재철;유철휘
    • 전기화학회지
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    • 제14권4호
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    • pp.201-207
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    • 2011
  • 수퍼커패시터는 다양한 응용범위를 갖는 유망한 에너지 저장장치로서 활발히 연구되고 있으며, 에너지 밀도 향상을 위하여 이온성 액체의 적용이 필요하다. 본 연구에서는 4급화 반응과 음이온 교환반응을 거쳐 4급 imidazolium 염을 생성하는 반응으로 두 종류의 EMI-$BF_4$를 합성하였다. $^1H$-NMR을 통하여 EMI-$BF_4$의 합성을 확인하였고 TGA를 통하여 열적안정성을 확인하였으며, 이때 합성된 이온성 액체를 열처리한 경우 열적 안정성이 향상되었다. LSV를 통하여 본 연구에서 합성한 EMI-$BF_4$가 4 V 이상의 넓은 전위창을 가지고 있어, 기존의 전해질 대비 우수한 전기화학적 안정성을 가지고 있음을 확인하였다. 충방전 실험 결과 본 실험에서 합성한 이온성 액체를 상용화 제품과 비교한 경우 용량은 각각 0.067 F 및 0.073 F로 측정되었다.

통계적 분석기법을 이용한 공정 운전 향상의 방법 (Process operation improvement methodology based on statistical data analysis)

  • Hwang, Dae-Hee;Ahn, Tae-Jin;Han, Chonghun
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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    • pp.1516-1519
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    • 1997
  • With disseminationof Distributed Control Systems(DCS), the huge amounts of process operation data could have been available and led to figure out process behaviors better on the statistical basis. Until now, the statistical modeling technology has been susally applied to process monitoring and fault diagnosis. however, it has been also thought that these process information, extracted from statistical analysis, might serve a great opportunity for process operation improvements and process improvements. This paper proposed a general methodolgy for process operation improvements including data analysis, backing up the result of analysis based on the methodology, and the mapping physical physical phenomena to the Principal Components(PC) which is the most distinguished feature in the methodology form traditional statistical analyses. The application of the proposed methodology to the Balst Furnace(BF) process has been presented for details. The BF process is one of the complicated processes, due to the highly nonlinear and correlated behaviors, and so the analysis for the process based on the mathematical modeling has been very difficult. So the statisitical analysis has come forward as a alternative way for the useful analysis. Using the proposed methodology, we could interpret the complicated process, the BF, better than any other mathematical methods and find the direction for process operation improvement. The direction of process operationimprovement, in the BF case, is to increase the fludization and the permeability, while decreasing the effect of tapping operation. These guide directions, with those physical meanings, could save fuel cost and process operator's pressure for proper actions, the better set point changes, in addition to the assistance with the better knowledge of the process. Open to set point change, the BF has a variety of steady state modes. In usual almost chemical processes are under the same situation with the BF in the point of multimode steady states. The proposed methodology focused on the application to the multimode steady state process such as the BF, consequently can be applied to any chemical processes set point changing whether operator intervened or not.

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탄소-수소 결합 활성을 이용한 1,5-헥사디엔의 하이드로아실화반응 연구 (Hydroacylation of 1,5-Hexadiene through C-H Bond Activation)

  • 전철호;한종수;김선일
    • 대한화학회지
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    • 제38권11호
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    • pp.833-840
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    • 1994
  • 8-Quinolinecarboxaldehyde (1)와 1,5-hexadiene (2)을 월킨슨 촉매(3)와 $AgBF_4(8)$의 혼합 촉매에서 반응시키면 8-quinolinyl 5-hexenyl ketone(4)와 8-quinolinyl 5-hexen-2-yl ketone (9)이 높은 수율로 반응초기에 생성된다. 가지달린 alkenyl 케톤인 9가 생성되는 이유는 월킨슨 촉매와 $AgBF_4(8)$의 반응에서 촉매에 빈 배위공간이 만들어져 1,5-hexadiene의 하이드로메탈레이션반응에서 $AgBF_4(8)$를 넣지 않았을 때보다는 입체장애가 적은 5.5각형의 중간체를 만들 수 있기 때문으로 설명된다. $AgBF_4(8)$의 사용량이 많으면 많을수록 9가 4보다 많은 비율로 생성되며, 장시간과 고온에서는 생성된 9와 4의 혼합물이 10과 5의 내부올레핀을 함유한 alkenyl 케톤으로 이성질화반응이 진행됨을 관찰할 수 있었다. 특히 고온으로 반응을 진행시킬수록 8-quinolinyl cyclopentylmethyl ketone (11)의 생성이 눈에 띄게 높아짐을 알 수 있었다.

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SWRO 전처리 공정에 적용된 DABF 내 Ball Media Filter 성능 평가 (Performance Evaluation of Ball Media Filter in DABF applied to SWRO pretreatment process)

  • 최석호;이정현;박성주;이영근;노형근;김용범
    • 한국물환경학회지
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    • 제35권6호
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    • pp.567-573
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    • 2019
  • DABF(Dissolve Air Flotation with Ball Filter) is developed as the DAF with the addition of a fiber ball at the lower part of the DAF. The DABF with a capacity of 4,500 ㎥/h was constructed at Gijang SWRO plant in Busan. Since the ball filter has high filtration rate, the loading rate of DABF was designed from 20 to 42 ㎥/h/㎡. When one DABF basin is in the back washing mode, the loading rate of other two DABF basins is increased to 42 ㎥/h/㎡. Turbidity at the BF outlet in DABF is <2 NTU at turbidity of 5-10 NTU at the BF inlet. If there is no algae bloom and turbidity is low in raw seawater, only BF in DABF is operated and meets <2 NTU at the BF outlet. Even if BF is operated at high hydraulic loading rates, no significant differential pressure increases and reduction in the turbidity removal rate is minimal in a day. Thus, DABF is the pre-treatment technology that provides stable water quality even with BF onlyoperation without DAF operation. Compared with the DAF, DABF requires additional facilities such as valves, piping, and drainage systems for backwashing the BF. But in terms of footprint and operating costs, DABF has more advantages than DAF. With DABF application, the load of the downstream filtration equipment is decreased so that the capacity of the filtration equipment can be reduced. Also, if the downstream filtration equipment is to be maintained the same regardless of DABF, the operating cost of DABF is less than DAF.

Inhibitory Effect of Benzofuran Compound on Cyclooxygenase

  • Min, Kyung-Rak;Ahn, Ki-Young;Chung, Eun-Yong;Lee, Yong-Rok;Kim, Yeong-Shik;Kim, Young-Soo
    • Natural Product Sciences
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    • 제10권6호
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    • pp.315-320
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    • 2004
  • Alpha-viniferin was previously isolated as a cyclooxygenase (COX)-2 inhibitor from Carex humilis (Cyperaceae) and is an oligomeric stilbene compound with benzofuran (BF) moieties in its chemical structure. In the present study, a chemically synthetic BF compound, named as 3,3-dimethyl-2,3,4,6,7,8,9,10,11,12,13,14,15,16,17,18-hexadecahydro-1H-benzo[b] cyclopentadeca[d]furan-1-one, was discovered to inhibit bacterial lipo polysaccharide (LPS)-induced prostaglandin $E_2$ $(PGE_2)$ production in macrophages RAW 264.7. The BF compound exhibited a selectively preferred inhibitory effect on COX-2 activity over COX-1 activity. Furthermore, BF compound inhibited LPS-induced COX-2 expression at transcription level. As a down-regulatory mechanism of COX-2 expression shown by BF compound, suppression of nuclear factor $(NF)-{\kappa}B$ activation has been demonstrated. BF compound inhibited LPS-induced $NF-{\kappa}B$ transcriptional activity and nuclear translocation of $NF-{\kappa}B$ p65, in parallel, but did not affect LPS-induced degradation of inhibitory ${\kappa}B{\alpha}$ protein $(I{\kappa}B{\alpha})$. Taken together, anti-inflammatory effect of BF compound on $PGE_2$ production was ascribed by its down-regulatory action on LPS-induced COX-2 synthesis in addition to inhibitory action on enzyme activity of COX-2.

Effects of by-product feed-based silage on feeding, rumination, and excretion in growing Hanwoo heifers

  • Kim, Young-Il;Lee, Sang Moo;Lee, Youn Hee;Lee, Myeon;Choi, Do Young;Kwak, Wan Sup
    • Journal of Animal Science and Technology
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    • 제57권1호
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    • pp.3.1-3.6
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    • 2015
  • This study investigated the effects of feeding by-product feed (BF)-based silage on the behavior of growing Hanwoo heifers. Twelve Hanwoo heifers (13.2 months-old, 315 kg body weight; four heifers per pen) were assigned to three diets: a rice straw (RS) diet (concentrate mix and free access to RS), a RS and BF-based silage (RSBFS) diet (concentrate mix and free access to RS and BF-based silage), and a BF-based silage (BFS) diet (concentrate mix and free access to BF-based silage). Behavior was recorded for 5 days using camcorders. Compared to the RS group, the BFS group showed 21.7% higher dry matter intake, shorter feeding, rumination, and chewing times, as well as longer resting time (p < 0.05). Although all groups exhibited similar drinking, urination, and defecation frequencies, the BFS group exhibited higher feeding rates, rumination efficiency, and chewing efficiency than the RS group (p < 0.05). Compared to the BFS group, the RSBFS group showed higher $peNDF_{8.0}$ intake (15.2% vs. 25.0% dry matter intake), longer feeding and sitting times, lower defecation frequency (p < 0.05), and similar rumination efficiency. In conclusion, complete replacement of conventional RS with BF-based silage reduced rumination and chewing activity in growing Hanwoo heifers, and BF-based silage feeding with large-particle straw is an effective approach in improving heifer behavior.

The Role of BF-7 on Neuroprotection and Enhancement of Cognitive Function

  • Chae, Hee-Sun;Kang, Yong-Koo;Shin, Yong-Kyu;Lee, Hyun-Jung;Yu, Ji-In;Lee, Kwang-Gill;Yeo, Joo-Hong;Kim, Yong-Sik;Sohn, Dong-Suep;Kim, Kyung-Yong;Lee, Won-Bok;Lee, Sang-Hyung;Kim, Sung-Su
    • The Korean Journal of Physiology and Pharmacology
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    • 제8권4호
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    • pp.173-179
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    • 2004
  • Amyloid ${\beta}-peptide\;(A{\beta})$ contributes to the pathogenesis of Alzheimer's disease (AD), causing neuronal death through apoptosis. In this study, the neuroprotective role of BF-7, extracted form sericultural product, was examined against $A{\beta}-induced$ toxicity in cultured human neuronal cell SKN-SH. In order to know if the BF-7 has positive role on the cognition and memory in human, the mixture of BF-7, DHA and EPA (BDE) was examined using Rey Kim and K-WAIS test with 50 healthy high school student. We report here that BDE significantly attenuated $A{\beta}-induced$ apoptosis through the reduction of ROS accumulation, and diminished caspase-like protease activity. Moreover, the memory index and memory preservation, and attentative concentration of BDE treated group for 1 month were significantly improved, in contrast to the case of placebo control treated with DHA and EPA. This result represent that the BF-7 play significant positive role on learning memory. Taken together, our result suggested the natural product BF-7 is a good substance for the brain functionally and physiologically.

Effect of Diclazuril on the Bursa of Fabricius Morphology and SIgA Expression in Chickens Infected with Eimeria tenella

  • Zhou, Bian-hua;Liu, Li-li;Liu, Jeffrey;Yuan, Fu-wei;Tian, Er-jie;Wang, Hong-wei
    • Parasites, Hosts and Diseases
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    • 제53권6호
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    • pp.675-682
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    • 2015
  • The effects of diclazuril on the bursa of Fabricius (BF) structure and secretory IgA (SIgA) expression in chickens infected with Eimeria tenella were examined. The morphology of the BF was observed by hematoxylin and eosin staining, while ultrastructural changes were monitored by transmission electron microscopy. E. tenella infection caused the BF cell volumes to decrease, irregularly arranged, as well as, enlargement of the intercellular space. Diclazuril treatment alleviated the physical signs of damages associated with E. tenella infection. The SIgA expression in BF was analyzed by immunohistochemistry technique. The SIgA expression increased significantly by 350.4% (P<0.01) after E. tenella infection compared to the normal control group. With the treatment of diclazuril, the SIgA was relatively fewer in the cortex, and the expression level was significantly decreased by 46.7% (P<0.01) compared with the infected and untreated group. In conclusion, E. tenella infection in chickens induced obvious harmful changes in BF morphological structure and stimulated the expression of SIgA in the BF. Diclazuril treatment effectively alleviated the morphological changes. This result demonstrates a method to develop an immunological strategy in coccidiosis control.

Neuroprotective Effects of a Butanol Fraction of Rosa hybrida Petals in a Middle Cerebral Artery Occlusion Model

  • Yang, Goeun;Park, Dongsun;Lee, Sun Hee;Bae, Dae-Kwon;Yang, Yun-Hui;Kyung, Jangbeen;Kim, Dajeong;Choi, Ehn-Kyoung;Hong, Jin Tae;Jeong, Heon-Sang;Kim, Hee Jung;Jang, Su Kil;Joo, Seong Soo;Kim, Yun-Bae
    • Biomolecules & Therapeutics
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    • 제21권6호
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    • pp.454-461
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    • 2013
  • The neuroprotective effects of a butanol fraction of white rose petal extract (WRPE-BF) were investigated in a middle cerebral artery occlusion (MCAO) model. Seven week-old male rats were orally administered WRPE-BF for 2 weeks and subjected to MCAO for 2 h, followed by reperfusion. Twenty-four h later, MCAO-induced behavioral dysfunctions were markedly improved in a dose-dependent manner by pretreatment with WRPE-BF. Moreover, higher dose of WRPE-BF not only decreased infarction area but also effectively reduced astrogliosis. The expression of inducible nitric oxide synthase, cyclooxygenase-2, and glial fibrillary acidic protein in MCAO model were markedly inhibited by WRPE-BF treatment. Notably, WRPE-BF decreased nitricoxide and malondialdehyde levels in the striatum and subventricular zone of stroke-challenged brains. These data suggested that WRPE-BF may exert its neuroprotective effects via anti-oxidative and anti-inflammatory activities against ischemia-reperfusion brain injury and could be a good candidate as a therapeutic target for ischemic stroke.