적응 등화기에서 데이터-재사용 LMS 알고리즘을 이용한 신호 간섭 제어

김원균,김동국,곽종서,나상동 조선대학교 에너지.자원신기술연구소 1999 에너지·자원신기술연구소 논문지 Vol.21 No.2

적응 등화기에서 LMS 알고리즘의 수렴 속도를 개선하기 위한 데이터 재순환 버퍼 구조를 제안한다. 폐기된 수신 데이터를 재활용함으로서 심볼 시간 주기에 적응 등화기의 에러를 이용한 가중치 갱신을 통해 제안된 알고리즘의 수렴특성을 분석하여 수렴 속도가 향상됨을 보인다. 컴퓨터 시뮬레이션 결과를 통해 스텝-크기 매개변수 μ가 증가됨에 따라 알고리즘의 수렴 속도가 상응하게 감소하고 또한, 스텝 크기 매개변수 μ의 증가는 실험적으로 계산된 학습 곡선에서 평균 자승 에러를 감소시키는 효과를 갖는다. 고유치 확산을 감소시킴에 따라 적응 등화기의 수렴속도를 천천히 감소시키고 평균 자승 에러의 안정-상태 값을 증가시키는 효과를 나타낸다. 따라서, 제안된 데이터 재순환 버퍼를 이용한 LMS 알고리즘의 수렴 특성을 개선시키고 계산의 복잡도를 증가시키지 않으면서 수렴속도를 (B+1)배만큼 증가시킨다는 것을 보인다. 컴퓨터 시뮬레이션 결과는 최악의 스텝 크기 매개변수와 고유치 확산 영역에 따른 평균 자승 에러를 분석하고 필터 알고리즘에서 신호간섭제어가 우수함을 입증한다. Data-recycling buffer structure to improve the convergence speed of LMS algorithm in adaptive equalizer is proposed. The improvement of convergence speed is shown by analyzing convergence characteristics of the proposed algorithm through updating weight using the error of adaptive equalizer when coefficients are multiply adapted in a symbol time period. As the step-size parameter μ is increased, the rate of convergence of the algorithm is correspondingly decreased through computer simulation result. Also, increasing the step-size parameter μ has the effect of reducing the variation in the experimentally computed learning curve. Reducing the eigenvalue spread has the effect of slowing down the rate of convergence of the adaptive equalizer and also increasing the steady-state value of the average squared error. Accordingly, the analysis shows that convergence speed can increase by (B+1) times, where B is the number of recycled data, as improving of convergence characteristics using the data-recycling buffer and not increasing complex of computation. The results of the computer simulation demonstrate analyzing mean squared error in accordance with the worst step-size parameter and eigenvalue spread and the superiority of signal interference control in the filter algorithm.

천연항균성 물질을 이용한 Vibrio vulnificus의 살균 및 독소생성 억제효과

조성환,서일원,최종덕,전상수,라택균,정수근,강동훈 國立統營水産專門大學 附設 水産科學硏究所 1993 수산과학연구소보고 Vol.4 No.-

생선회용 해산물에 오염되어, 생식한 경우 발생되는 패혈병의 원인균주인 Vibrio vulnificus의 생육 및 독성생성을 억제할 목적으로 천연 항균제인 Grapefruit종자추출물(GPSE)을 이용하여 그 항균효과를 검토하였다. In vitro 시험결과, Vibrio vulnificus에 대한 GFSE의 생육최소저해농도는 50~100 ppm 정도이었으며, Vibrio vulnificus 균체세포틀 100 ppm 농도의 GFSE 용액으로 처리하고 전자현미경 촬영시료로 조제하여 촬영한 후, 미생물형태을 무처리대조구와 비교, 검토한 결과, GFSE 처리로 세포막 기능이 파괴되어 세포내용물이 균체외부로 유출되어 균체의 생육이 억제되고 균체내부가 빈 ghost 형태의 균체수가 증대되어 GFSE의 항균효과를 확인할 수 있었다. 한편, 생선회용 해산물에 GFSE를 근육주사하고 Vibrio vulnificus를 접종한 수조내에서 사육하여 채취한 어육부를 마쇄하여 일정량씩을 표준사료에 첨가해서 통닭용 병아리를 실험동물로 하여 사양실험을 실시한 결과. 체중증가율, 단백질이용효율, 혈청내 효소활성, 혈청의 주요성분함량 등에 있어서, GFSE 처리수조내에서 사육한 해산물을 첨가한 시료시험구의 경우, 무첨가사료처리구와 비교할 때 뚜렷한 차이를 목격할 수 없었으며, GFSE 첨가에 따른 실험동물의 성장저해 또는 독성현상을 유발하지 않음을 알 수 있었다. 아울러, 각 처리구에서 사양한 해산물의 어육부에 오염된 Vibrio vulnificus의 균수를 측정한 결과, 250ppm 이상의 GFSE 처리구에서는 Vibrio vulnificus를 전혀 검출할 수 없었다. To prevent food-poisoning outbreaks by Vibrio vulnificus the antimicrobial efficacy of grapefruit seed extract (GFSE) was examined. Minimal inhibitory concentration (in vitro) for the microorganism was found to be 50~100 ppm. Transmission electron micrographs of Vibrio vulnificus showed the biocidal action of this natural antimicrobial agent would be related to specific respiratory effect coupled with the destruction of permeable function of microbial cell membrane. After Anguilla japonia GFSE-injected to the body was incubated in the seawater contaminated by Vibrio vulnficus the fish meats were taken up, mixed with control diet and used as a diet in the feeding experiment. In this experiment the effect of GFSE treated with fish muscle on body weight protein efficiency ratio, serum enzymes and serum blood component of broiler chicks was investigated. It is proved from this study that there is neither Vibriosis nor toxicity associated with GFSE itself and fish meats treated with it when it is injected to the fish body at a level of 250 ppm or less.

고양이의 子宮支配神經의 電氣生理學 硏究

林泰均,羅重烈,洪性鳳 고려대학교 의과대학 1986 고려대 의대 잡지 Vol.23 No.1

A method was described for recording in vivo evoked potential of afferent fibers supplying the cat's uterus from the whole dorsal roots between T11 and S4 spinal segments. 1. The evoked potentials were recorded from T12, T13, L1, L7, S1, S2, and S3 segments of the spinal dorsal roots 71-hen the uterus was stimulated electrically with the intensity of 50V, duration of stimuli of 1 ms, and the frequency of stimuli of 5Hz. 2. Three types of the evoked potentials mere observed from the above dorsal roots. 1) A-β fibers from TI3 and S2 segments had the conduction volocity ranging from 24~37m/sec to 27~46m/sec. These fibers mere seemed to conduct touch and pressure sense from the uterus to the spinal cord. 2) A-β fibers from the dorsal root segments of T12, 13, L1, 7, & S1, 2, 3, had the conduction velocity ranging from 2.7m/sec to 31.6m/sec and seemed to conduct the pain and temperature sense. 3) C1 fibers from T12 dorsal root segments had the conduction velocity ranging from 1.5 m/sec to 2.2m/sec. These fibers were presumed to conduct the pair and temperature sense from the uterus. 3. The compound action potential evoked by stimulation of the uterus usually had three or four peaks, conducted at 1.5~2.2m/sec, 2.8~31.6 m/sec, and 23.5~45.5 m/sec respectively, and were likely to correspond to the fast afferent, middle, and slow afferent fibers respectively. 4. It seemed that the impulses from the uterus probably conducted through myelinated, thin myelinated and unmyelinated nerve fibers. 5. The blood pressure was increased by the electric stimulation on the uturus, but the rate of increase was noted to diminish as the dorsal roots were cut in the order of from S4 to T11. The factor for the increased BP seemed due to the painful stimulation on the uterus.

증례 : 감염 ; 낼리딕산 내성 Salmonella enteritidis에 의한 급성 대퇴골 골수염 1예

나성균 ( Seong Kyun Na ),김태준 ( Tae Jun Kim ),이정아 ( Jeong A Lee ),이승순 ( Seung Soon Lee ),고성혜 ( Sung Hye Koh ),김태영 ( Tae Young Kim ),김한성 ( Han Sung Kim ) 대한내과학회 2015 대한내과학회지 Vol.88 No.3

비장티푸스성 살모넬라균은 주로 급성 위장염을 일으키고 자연 호전되는 경우가 많지만 균혈증이나 전이성 국소감염을 일으킨 경우 항생제 치료가 필요하다. 3세대 cephalosporin, fluoroquinolone이 1차 치료제로 사용되나 1990년대부터 낼리딕산 내성 균주에 의한 감염이 보고되었고 이 경우 fluoroquinolone에 감수성임에도 불구하고 임상적으로 치료 반응이 지연되거나 치료에 실패하는 경우가 발생했다. 국내에서도 낼리딕산 내성 균주가 빠르게 증가하고 있으며 비장티푸스성 살모넬라 감염에서 혈청형 또는 낼리딕산 내성을 확인하여 항생제를 선택하는 것이 치료 실패를 줄이기 위한 방법이 될 것으로 생각된다. 저자들은 건강한 환자에서 발생한 낼리딕산 내성 S.enteritidis에 의한 골수염 및 골막 농양을 골조직 투과력 및 경구 흡수율이 좋은 고용량 flu-oroquinolone을 16주간 투여로 부작용 없이 성공적으로 치료한 예를 경험하여 문헌고찰과 함께 보고하는 바이다. Infection with nontyphoidal Salmonella most often results in self-limited acute gastroenteritis. However, occasionally it causes bacteremia and localized infection requiring antibiotic treatment. A third-generation cephalosporin or fluoroquinolone is often the first choice of antibiotic. However, there has been an increase in nalidixic-acid-resistant nontyphoidal Salmonella with decreased fluoroquinolone susceptibility. Although there have been many cases reported of nontyphoidal Salmonella, no cases of nalidixic- acid-resistant nontyphoidal Salmonella have been reported in Korea. Here, we report on the case of a 61-year-old man with a diagnosis of acute osteomyelitis and periosteal abscess of the femur caused by nalidixic-acid-resistant Salmonella enteritidis. He was treated successfully with prolonged administration of a high-dose of ciprofloxacin and drainage of the abscess. (Korean J Med 2015;88:340-345)

마이크로그리드 간 P2P 에너지 거래를 위한 거래 운영 알고리즘

나의균(Ui-Kyun Na),김준성(Jun-Sung Kim),정재성(Jae-Sung Jung) 대한전기학회 2021 전기학회논문지 Vol.70 No.9

Research on microgrids for efficient use of distributed resources and renewable energy is being actively conducted. In domestic, FIT(Feed-in-Traiff) was applied to increase the penetration rate of renewable energy and distributed resources, and research is being conducted to enable efficient operation through predict of power generation, demand forecast and anomaly detection algorithm by combining with AI to improve the stability of MG operation. A electric power transaction model between MGs, like P2P(peer to peer) trading, has been proposed, but it is still incomplete. In this paper, we propose electric power transaction model between MGs. A correlation and dependence between weather elements and loads is performed and a load prediction model is proposed. In addition, we propose a transaction calculation algorithm that determines the transaction unit price for P2P energy transactions between MGs and a power transaction model which is an optimal matching algorithm for transactions between MGs where both sellers and buyers generate profits.

A case of tinea faciei misdiagnosed as rosacea

( Na Gyeong Yang ),( Tae Heum Park ),( Dong Sung Kim ),( Jung Eun Kim ),( Sul Hee Lee ),( Moon Kyun Cho ) 대한피부과학회 2022 대한피부과학회 학술발표대회집 Vol.73 No.2

Biological Activity of Waxy and Non Waxy Type Barley (Hordeum vulgare L.) and Barley Byproduct Extracts

Na-Young Lee,Mi-Ja Lee,In-Duck Choi,Yang-Kil Kim,Sang-Kyun Cho,Jae-Seong Choi,Kee-Jong Kim 한국작물학회 2010 한국작물학회 학술발표대회 논문집 Vol.2010 No.04

Barley (Hordeum vulgare L.) and barley byproduct, waxy and non waxy genetic type, were prepared and investigated for its biological activity. The total phenolic contents, tyrosinase and xanthin oxidase inhibition activity of the barley extracts were measured and compared with those of a barley byproducts extracts powder. The contents of total phenolic compounds of the barley byproducts, waxy and non waxy type, were 18.60 and 17.92 mg/g of sample, respectively. Inhibition rates (%) of the mushroom tyrosinase of the waxy type barley and barley byproducts extracts powder were 16.30 and 33.60% at 250 ppm, respectively. Tyrosinase inhibition activity of barley byproduct extracts regardless of waxy and non waxy type showed higher than that of arbutin (5%). The samples showed an inhibition effect of xanthin oxidase. At 2,500 ppm of sample concentration, the inhibition effect of xanthine oxidase of waxy type barley (WB), non waxy type barley (NB), waxy type barley byproducts (WBP), and non waxy type barley byproducts (NBP) was 9.92, 16.06, 14.11, and 13.86%, respectively.

Effects of single-sided inferior turbinectomy on nasal function and airflow characteristics

Na, Yang,Chung, Kang Soo,Chung, Seung-Kyu,Kim, Sung Kyun Elsevier 2012 Respiratory physiology & neurobiology Vol.180 No.2

<P><B>Graphical abstract</B></P><P><ce:figure id='fig0005'></ce:figure></P><P><B>Highlights</B></P><P>► We simulate nasal airflows in 3 post-surgery models by PIV and CFD. ► We consider gains and losses of inferior-turbinectomy. ► We study the changes in local/global thermo-/fluid-dynamic properties. ► We correlate flow properties with obstructions and prognosis of surgery. ► We conclude that results were affected by the turbinate resection volume, position, and manner.</P> <P><B>Abstract</B></P><P>Knowledge of airflow characteristics in the nasal cavity is essential to understanding the physiologic and pathologic aspects of nasal breathing. Airflows inside post-surgery models were investigated both experimentally and numerically to simulate the inferior turbinectomy. The left cavities of all three models are normal and right cavity is modified by (1) excision of the head of the inferior turbinate, (2) resection of the lower fifth of the inferior turbinate, and (3) resection of almost the entire inferior turbinate. Thin-slice CT (computed tomography) data (0.6mm deep) and meticulous refinement of the model surface by over a decade-long collaboration between engineers and an experienced ENT doctor resulted in the creation of sophisticated nasal cavity models. After numerical experiments and validation by comparison with the PIV results, the CFD code using the Reynolds stress turbulent model and variable temperature boundary condition on the mucosal wall was chosen as the proper numerical framework. Both global quantities (pressure drop, flow rate ratio, total wall heat transfer) and local changes (velocity, temperature, humidity, pressure gradient, and wall shear stress) were numerically investigated. The turbinectomy obviously altered the main stream direction. The flow rate in the upper airway near the olfactory slit decreased in models (1) and (3). This may weaken the olfactory function of the nose. Fluid and thermal properties that are believed to be related with physiology and prognosis are dependent on turbinate resection volume, position, and manner. Widening of the inferior airway does not always result in decreased flow resistance or wall heat transfer. The gains and losses of inferior turbinectomy were considered by analysis of the post-surgery model results. Nasal resistance was increased in model (1) due to sudden airway expansion. Nasal resistance increased and the wall heat transfer decreased in model (3) due to sudden airway expansion and excessive reduction of the mucosal wall surface area. Local shear stress and pressure gradient levels were increased in models (1) and (3).</P>

Effect of the average particle size and the surface oxidation layer of silicon on the colloidal silica particle through direct oxidation

Na, Won Kyun,Lim, Hyung Mi,Huh, Soo Hyun,Park, Sang Eon,Lee, Youn-Seoung,Lee, Seung Ho Elsevier 2009 Materials science and engineering B. Advanced Func Vol.163 No.2

<P><B>Abstract</B></P><P>Colloidal silica was prepared using a direct oxidation process of silicon powders with different purities, average particle sizes, and surface oxidation layer thicknesses in a water solvent with the base catalysts. Purities of 97.00–99.96% and average particle sizes of 200 and 500 mesh of silicon starting materials were evaluated. The materials were thermally oxidized for 3, 16, and 30h to observe the effect of the surface oxidation layer on the formation of colloidal silica. The longer the thermal oxidation time, the higher the oxide layer thickness on the silicon, and the larger the average size of silica particle observed in the product of colloidal silica when silicon particles had the oxide layer up to approximately 50nm. When the oxide film was higher than 50nm, the silica particle size did not increase with an increase in the oxide layer of silicon. The dependence of the average particle silica size on the oxide layer thickness of silicon was observed to be smaller in the colloidal silica from the 200 mesh size of silicon than from the 500 mesh size. The average particle size of silicon was found to affect the average particle size of silica in the direct oxidation, however the correlation between the purity of silicon and the average particle size of silica was not determined as it fell outside the range of this experiment.</P>

LuxS and smcR Quorum-Sensing System of Vibrio vulnificus as an Important Factor for In Vivo Survival

( Na Ri Shin ),( Chang Ho Baek ),( Deog Yong Lee ),( Young Wook Cho ),( Dae Kyun Park ),( Ko Eun Lee ),( Kun Soo Kim ),( Han Sang Yoo ) 한국미생물생명공학회 2005 Journal of microbiology and biotechnology Vol.15 No.6