반달형 베플을 갖는 이중벽튜브 중기발생기의 특성 평가

위명환,김성오,전원대,어재혁,김진환 한국공업화학회 2004 응용화학 Vol.8 No.2

The DWTSG concept is proposed as a advanced steam generator of liquid metal reactor to avoid sodium-water reaction incidents in the SG. The optimization of steam generator from economic viewpoint is to minimize the total cost of heat transfer area and pumping power. The baffles are primarily used in shell and tube steam generator for inducing cross flow over tube bundles, and as a results, improving heat transfer performance. In this paper a computer based design method, which covers segmentally baffled steam generator is developed for preliminary DWTSG design. And parametric sensitivity studies are done to determine required heat transfer area to meet the specified heat capacity by calculating minimum or allowable shell-side pressure loss.

이중벽튜브 Na-CO₂ 열교환기의 열적특성 연구

위명환,김성오,어재혁,김진환 한국공업화학회 2005 응용화학 Vol.9 No.1

A Na-CO₂ heat exchanger is one of the key equipments in the concept of coupling the supercritical CO₂ Brayton cycle to the KALIMER-150 design. The exchanger is a shell and tube counter flow type with a hot sodium on the shell side and a supercritical carbon dioxide on tube side. In this study, a computational design methodology was developed and the sensitivity study was done on the major design parameters for the development of preliminary design. In the designing process, the design requirements are pressure drops and sodium maximum velocity in the shell side and aspect ratio of the heat exchanger. The evaluation revealed that the gap design of doubel wall tube has noticeable effects on the thermal-hydraulic characteristics of the heat changer. Maintaining the operating condition to be identical to those of KALIMER-150, the heat transfer area of He packed case was 4 times more than that of LBE packed case.

양식산 터봇, Scophthalmus maximus에서의 Irido-like virus 감염

김위식,김기홍,김춘섭,김영진,정성주,정태성,신이치, 키타무라,마모루, 요시미즈,오명주 한국어병학회 2003 한국어병학회지 Vol.16 No.3

본 연구는 병리조직학적 및 전자현미경적 방법을 통해 양식산 turbot에서 발생하는 irido-like virus의 감염증을 소개하고자 한 것이다. 2003년 6월 전북 고창 소재 육상수조에서 양식중인 turbot치어에서 50∼70%의 대량폐사가 발생하였다. 병어는 사료섭취가 저하되고 힘없이 유영하다 폐사되었으며, 죽기 직전의 어류는 복부가 팽만되고 안구가 돌출되며 체색이 옅어지는 증상을 보였다. 해부학적 조사 결과, 아가미 빈혈과 간이 퇴색되어 있었으며, 특히 비장조직이 심하게 비대되어 있었다. 병어에 대한 조직학적 검사에서 비대 세포를 특징으로 하는 특이 병변이 주로 신장과 비장의 조혈조직에서 관찰되었으며, 아가미, 심장, 위, 장, 간, 췌장, 지방 조직에서도 관찰되었다. 그리고 전자현미경적 관찰 결과, 비대 세포의 세포질내에서 육각형의 지름이 136∼159 ㎚인 Irido-like virus를 관찰할 수 있었다. The high mortality of cultured juvenile turbot, Scophthalmus maximus occurred in Gochang on June, 2003. The diseased fish was lethargic with reduced feed intake. Grossly, these fish showed pale body, abdominal extension and exophthalmia. The dominant internal gross features of diseased fish were severely enlarged spleen, pale gills and or liver. Diseased fish histologically showed basophilic enlarged cells in the kidney, spleen, gill, heart, stomach, intestine, liver, pancreas and adipose tissue. Transmission electron microscopy (TEM) reveled hexagonal virions in the cytoplasm of necrotic cells. The viral particles lead a central electron-dense core and an electron translucent zone, and were 136-159 nm in diameter. These results suggest that the virus belonging to the iridoviridae was responsible for the mortality of cultured juvenile turbot.

국내의 양식산 무지개송어 성어로부터 분리된 IHNV의 G protein gene에 대한 연구

김기홍,김위식,김춘섭,김영진,정태성,신이치, 키타무라,정성주,오명주 한국어병학회 2003 한국어병학회지 Vol.16 No.3

An Infectious hematopoietic necrosis virus strain (IHNV-RTK) was isolated from cultured rainbow trout at Kumi in Korea during 2000 and 2001. In the RT-PCR amplification with the specific primer set designed from IHNV G protein region, a 540 bp PCR product was amplified from the RTK strain. The RTK strain showed higher sequence homology with the published IHNV G protein genes (RB-76, LR-73, Col-85, and Carson-89).

格技種目 選手들의 心拍數 回復에 關한 硏究

金義榮,金振杓,鄭渭坤 龍仁大學校 1992 용인대학교 논문집 Vol.8 No.-

University Students Haue Been Chssen 25 Peoples among Hapkido, Boxer, Ssireum playens Luy measuring the amount of heath that was Pioduced using a Piocess Called sitting sttitude, lying down, standing, and the saliyect breathes aften 100m Running that was estimate throuth each others Type of body measwring the amount of circuit Sgstems. According to the study allewed these conclusions. ① Aftes 100m running that the bseardown of enengg resalted in heat and that estimate the Hapkido playes 160.4±1.3times/min sate, Boxing Playes 160.6±3.7times/min sate, Ssireum playes 160.8±7.1time/min sate, Hapkido playes could be estimated much mone highly lug measuring the amount of 160.8±7.1times /min sate. ② A.Breath of nestfal prion to the test that Hapkido peages was estimatde 68.4±52times/min, Boxes 68.3±6.1 time /min, Ssireum playes 76.1±6.2time/min, Ssireum peayes could be estimated mach mone lowgy buy measuning, ③ A body of neetbul prion to the test that estimated the hasten buy the bmeardown of Rest standing than bying down. ④ Aften 100m Running that estimated the fasten bying down mose standing. ⑤ The bneardown of heat abtes 100m running that Boxing playes the most bastest and ssireum lowest. The result abtained bon the analysio of the association between Hapkldo's beuel of breathing attitude, Boxing and Ssireum playes wese mose exescise the highes Hapkido than anothes exercise.

경도변화에 따른 Al의 밀링가공시 가공 특성에 관한 연구

김성일,이상진,김민호,김태영,이위로 한국공작기계학회 2004 한국공작기계학회 추계학술대회논문집 Vol.2004 No.-

The cutting tests of aluminum alloy for various hardnesses were carried out using CNC milling machine. The surface roughness(Ra, Rmax) of cut surface and cutting forces are measured at various cutting conditions such as spindle speed, feed speed and hardness. In the CNC end-milling, the surface roughness increases as feed speed increases and decreases as spindle speed increases. However, the bulit-up edge has occurred on in case of low hardness and low feed speed. In experimental conditions, as the hardness of aluminum alloy increases, the surface roughness(Ra, Rmax) decreases

벨로우즈방식의 정밀 나사 체결기

정규원,오의진 한국공작기계학회 2001 한국생산제조학회지 Vol.10 No.5

A screw driver is widely used in assembling machine parts or electronic products such as the printed circuit board with a housing. As the parts to be assembled becomes small and precise, the higher precision of the controlling screw driver torque is required. However, because the operator controls the fastening torque based on experience, it must be inexact and the setting procedure will be time consuming job. Thus the screw driver which can exactly control the fastening torque is developed utilizing a bellows in this paper. The bellows is expanded by the inner air pressure and contracted by the spring operation. The bellows type driver is composed of a clutch mechanism with two solenoid valves and a pressure sensor. Those valves are controlled using the detected bellows pressure by the sensor. When the pressure reaches the setting value, the exit solenoid valve is opened to release the air pressure from the bellows so as not to deliver further torque. Through a series of experiments, the performance is examined and verified.

개입이 있는 비선형 시계열자료에 대한 예측방법의 비교

이성덕,김주성,이위진 성균관대학교 응용통계연구소 2002 통계연구 Vol.10 No.-

시계열 자료는 공휴일, 파업, 석유파동, 정책변화 등과 같은 외부사건에 영향을 받아서 급격한 변화를 나타낸다. 이러한 외부사건의 결과로 발생된 관측값들을 특이값이라 하며, 외부사건의 시기와 원인이 알려진 경우에는 이러한 외부사건을 개입이라 한다. 이러한 개입으로 인하여 자료를 모형화하기 어려운 경우가 많다. 그러므로 개입의 유형과 효과를 분석하여 모형화하는 것은 매우 중요하다. 본 논문에서는 개입을 가진 선형모형에 대해 연구하고 ARCH, GARCH 모형과 같은 비선형 모형과 비교하였다. 또한 예측에 있어서는 Tong(1990)에 의해 제안된 결합예측 방법과도 비교하였다. 실증분석에서는 개입이 있는 선형시계열 모형, 개입이 있는 비선형시계열 모형, 그리고 결합예측모형을 이용하여 RMSE를 기준으로 예측력을 비교하였다. Time series data are influenced by the external events such as holiday, strike, oil shock, and political change, so the external events cause a sudden change to the time series data. We regard the observation as outlier that occurred as a result of external events. In general, it is called intervention if we know the period and the reason of external events, and if makes an analyst difficult to establish a time series model. therefore, it is important that we analyze the styles and effects of intervention. In this paper, we have been studied about the linear time series model with invention and compared with nonlinear time series models such as ARCH, GARCH model and also we compared with the combination prediction method that Tong(1990) introduced. In the practical case study, we compared prediction power with RMSE among linear, nonlinear time series model with intervention and combination prediction method.

Inhibition of Biphasic Ethylene Production Enhances Tolerance to Abiotic Stress by Reducing the Accumulation of Reactive Oxygen Species in Nicotiana tabacum

Wi, Soo-Jin,Jang, Su-Jin,Park, Ky-Young Korean Society for Molecular and Cellular Biology 2010 Molecules and cells Vol.30 No.1

Reactive oxygen species (ROS), such as $H_2O_2$, are important plant cell signaling molecules involved in responses to biotic and abiotic stresses and in developmental and physiological processes. Despite the well-known physiological functions of ethylene production and stress signaling via ROS during stresses, whether ethylene acts alone or in conjunction with ROS has not yet been fully elucidated. Therefore, we investigated the relationship between ethylene production and ROS accumulation during the response to abiotic stress. We used three independent transgenic tobacco lines, CAS-AS-2, -3 and -4, in which an antisense transcript of the senescence-related ACC synthase (ACS) gene from carnation flower (CARACC, Gen-Bank accession No. M66619) was expressed heterologously. Biphasic ethylene biosynthesis was reduced significantly in these transgenic plants, with or without $H_2O_2$ treatment. These plants exhibited significantly reduced $H_2O_2$-induced gene-specific expression of ACS members, which were regulated in a time-dependent manner. The higher levels of NtACS1 expression in wild-type plants led to a second peak in ethylene production, which resulted in a more severe level of necrosis and cell death, as determined by trypan blue staining. In the transgenic lines, upregulated transcription of CAB, POR1 and RbcS resulted in increased photosynthetic performance following salt stress. This stress tolerance of $H_2O_2$-treated transgenic plants resulted from reduced ethylene biosynthesis, which decreased ROS accumulation via increased gene expression and activity of ROS-detoxifying enzymes, including MnSOD, CuZnSOD, and catalase. Therefore, it is suggested that ethylene plays a potentially critical role as an amplifier for ROS accumulation, implying a synergistic effect between biosynthesis of ROS and ethylene.

Two Species of the Genus Oncaea (Copepoda, Poecilostomatoida, Oncaeidae) from the East Sea, Korea

Wi, Jin-Hee,Suh, Hae-Lip,Yang, Han-Soeb,Soh, Ho-Young The Korean Society of Oceanography 2008 Ocean science journal Vol.43 No.4

Oncaea venusta Philippi, 1843 has been known as having some different size groups, but recent genetic study for cyt b and ITS 1 (Elvers et al. 2006) suggests that these size groups can be considered as different species. Of these size groups, the largest O. venusta Philippi and the smallest O. venella Farran, 1929 were first described in Korean waters. The latter is easily distinguishable from the former in the following characteristics in addition to its small size: (1) length to width ratio of genital double somite of two genders smaller, and (2) female second pediger bearing inconspicuous dorso-posterior swelling. Oncaea venusta and O. venella co-occur in Korean waters during spring to fall, but their occurrence patterns seasonally differ: the former shows higher density in fall while the latter does in summer.