• 대한전자공학회:학술대회논문집
• /
• 대한전자공학회 2001년도 하계종합학술대회 논문집(2)
• /
• pp.309-312
• /
• 2001

A primitive gas classification system which can classify limited species of gas was designed and simulated. The 'electronic nose' consists of an array of 4 metal oxide gas sensors with different selectivity patterns, signal collecting unit and a signal pattern recognition and decision Part in PLD(programmable logic device) chip. Sensor array consists of four commercial, tin oxide based, semiconductor type gas sensors. BP(back propagation) neutral networks with MLP(Multilayer Perceptron) structure was designed and implemented on CPLD of fifty thousand gate level chip by VHDL language for processing the input signals from 4 gas sensors and qualification of gases in air. The network contained four input units, one hidden layer with 4 neurons and output with 4 regular neurons. The 'electronic nose' system was successfully classified 4 kinds of industrial gases in computer simulation.

• Mycobiology
• /
• 제40권3호
• /
• pp.210-213
• /
• 2012

Sooty blotch and flyspeck (SBFS), a disease caused by a complex of fungi, results in substantial economic losses for commercial growers of sweet persimmon (Diospyros kaki L.) in Korea. However, many species causing SBFS in Korea have not been identified and sources of inoculum are uncertain. Based on mycological characteristics, pathogenicity, and molecular data, the causal fungi were identified as Dissoconium sp. and Zygophiala wisconsinensis. This is the first report of SBFS of sweet persimmon in Korea.

• Ocean and Polar Research
• /
• 제32권4호
• /
• pp.483-488
• /
• 2010

Since 2000 fry releasing programs in Korea have significantly expanded in order to support the commercial fishing industry through recruitment enhancement of targeted species. Here we investigate the economic effectiveness of the Olive flounder (Paralichthys olivaceus) fry releasing program in Korean waters. The market survey method was used in our analyses. Results show that the B/C ratio, as an indicator of economic evaluation, is 2.56 in the East Sea region, 9.45 in the South Sea region, and 1.34 in the West Sea region, which indicates that the fry releasing program is economically feasible but the economic effectiveness varies from region to region.

• 한국연소학회지
• /
• 제14권2호
• /
• pp.18-25
• /
• 2009

Fuel lean reburning method is very attractive way in comparison with conventional reburning method for reducing NOX. Meanwhile, the knowledge of the how flue gas re-circulated, temperature distribution and species concentration is crucial for the design and operation of an effective fuel lean reburning system. For this reason, numerical analysis of fuel lean reburning system is a very important and challenge task. In this work, the effect of fuel lean reburn system on NOX reduction has been experimentally and numerically conducted. Experimental study has been conducted with a 15kW lab scale furnace. Liquefied Petroleum Gas is used as main fuel and reburn fuel. To carry out numerical study, the finite-volume based commercial computational fluid dynamics (CFD) code FLUENT6.3 was used to simulate the reacting flow in a given laboratory furnace. Steady state, three dimensional analysis performed for turbulent reactive flow and radiative heat transfer in the furnace.

• Fisheries and Aquatic Sciences
• /
• 제13권3호
• /
• pp.257-259
• /
• 2010

This is the first report of Snyderina yamanokami, from the subfamily Tetraroginae of the family Scorpaenidae, collected in Korea. The specimen (175.3 mm long) was caught in the coastal waters of Jeju Island on a commercial longline hook on 9 September 2009. This species is characterized by the following morphological traits: 9-11 dorsal fin rays, 5-6 anal fin rays, 13-15 pectoral fin rays, 5 ventral fin rays, pectoral fin tip reaching or extending past the origin of the anal fin, palatines toothless, and four dark spots on the middle of the body. We suggest a new Korean name, "Keun-mi-yeok-chi," for S. yamanokami.

• 한국연초학회지
• /
• 제17권2호
• /
• pp.109-113
• /
• 1995

Nicotiana repanda has resistance to many important tobacco diseases but no tobacco cultivars are currently available that carry risistance genes derived from this species. Numerous attempts to hybridize N, repanda with commercial tobacco cultivars have been largely unsuccessful because of cross incompatibility or the uncovering of lethal genes. In vitro pollination of placenta attached ovules was useful in by passing prezygotic barriers for interspecific hybrid combination between N.tabacum cv. NC82 and N. repanda. Six days after in vitro pollination of N. tabacum cv. NC82×N. repanda, enlarged ovules on plancenta were removed and transferred into ovule culture medium of kitsch and kitsch (1969). Within 15 days of ovule culture, germination occurred. Most of the hybrid seedlings obtained had poor root system and finally died, while few of them had good root system and grew well.

• Journal of the Korean Wood Science and Technology
• /
• 제2권2호
• /
• pp.4-4
• /
• 1974

본 보고는 1952년 1월부터 3월중순까지 약 50일간에 걸쳐 FAO주최하에 개최된 극동 임업 기술자 강습회에 출석시 마레이 반도산 중요 목재 즉 열대성 유용목재에 대하여 그 해부학적 특징을 연구한 결과이다. 남방 열대산 목재는 대부분이 활엽수이며 그 특이한 점은 온대수목에서 조성되는 연륜은 볼 수 없고 그 대신 생장륜(growth ring)을 가지는 점과 특히 유조직(parenchyma)이 발달되고 있는 점을 들 수 있다. 남방재의 재질은 강한 것이 많고 그 목리(grain)는 대개는 교착목리(interlocked grain)로 되어서 미려한 무늬(figure)를 나타내는 것이 많으므로 기구재로서 많이 애용되고 있다. 주로 관찰된 육안 및 렌스(X10)에 의한 해부학적 성질은 재색, 광택, 무늬, 목리, 경도, 비중, 도관의 배열, 도관의 크기, 도관의 수, 도관내의 함유물질, 유조직의 배열, 방사조직의 수 및 크기였다.

• 수산해양기술연구
• /
• 제13권2호
• /
• pp.5-7
• /
• 1977

생식소 회복초기의 생태에 관한 조사결과는 다음과 같다. 1.까나리의 결장과 체중의 상대성장식은 다음과 같다. $W=0.0010114L^{2\cdot7281024}$ 2.체중,생식소 및 내장 중량 생식소으 ㅣ체중에 대한 비율은 0.27$\sim$0.87%로 생식소는 회복초기의 것이다. 내장의 체중에 대한 비율은 10.34$\sim$11.86%로 산란군의 생식소의 체중에 대한 비율과 비등하다. 3.척추골의 수 척추골의 평균치와 표준편차는 다음과 같다. $64.597\pm1.307$

• 한국철도학회:학술대회논문집
• /
• 한국철도학회 2008년도 춘계학술대회 논문집
• /
• pp.1740-1746
• /
• 2008

The present study performed numerical investigation to analyze the smoke behavior in the rescue station by using the commercial CFD code (FLUENT Ver 6.3). The present study adopted a 10MW ultrafast mode for simulation, and it also used the MVHS(Modify Volumetric Heat Source) model modified from the original VHS(Volumetric Heat Source) model in order to treat the product generation and the oxygen consumption under the stoichiometric state. In addition, the present simulation includes the species conservation equation for the materialization of heat source and the estimation of smoke movement. From the results, the smoke flows are moving along the ceiling because of thermal buoyancy force and as time goes, the smoke gradually moves downward at the vicinity of the entrance. Moreover, without using ventilation, it is found that the smoke flows no longer spread across the cross-passages because the pressure in the non-accident tunnel is higher than that in the accident tunnel.

• Journal of the Korean Wood Science and Technology
• /
• 제36권2호
• /
• pp.9-20
• /
• 2008

Anatomical comparison of 3 North American species with commercial name of redcedar was executed to provide taxonomic information for prevention of confusion and establishment of sound business transaction in the wood market. Eastern redcedar (Juniperus virginiana) and southern redcedar (Juniperus silicicola) could not be separated on the basis of microstructure and ultrastructure of wood. Western redcedar (Thuja plicata), however, appeared to be obviously separated from eastern and southern redcedar in a number of microscopic and ultramicroscopic features. Useful features for separating these two groups were intercellular spaces in transverse surface, latewood width, radial intertracheid pitting, warty layer and pits with torus extensions in tracheids, ray composition, nodular end walls in ray parenchyma cells, and cross-field pitting.