• 대한임상검사과학회지
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• 제44권4호
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• pp.199-204
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• 2012

The purpose of this study is to examine the population density of the mosquito species, and to provide the basic data related to vector mosquitoes to manage the possible epidemic diseases. During a 4-year investigation (2001, 2002, 2004, and 2006), we collected the specimens of the mosquitoes at pier no. 1, 3 and 5 of Busan port with light traps from sunset until the next day morning from April to October each year. Through the research, we collected 5,985 mosquito specimens in total and found 7 mosquito species belonging to 3 genera. A total of 1,575, 1,473, 1,478 and 1,459 mosquito specimens were collected in 2001, 2002, 2004 and 2006, respectively. Among them, 5,568 (93.0%) specimens were Culex pipiens pallens, the West Nile virus infection vector, which showed the highest density among the specimens. The population densities of the other species were: 295(4.9%) Culex tritaeniorhynchus, 94(1.5%) Aedes togoi, 12(0.3%) Aedes albopictus, 10(0.2%) Anopheles sinensis, 4(0.1%) Aedes vexans nipponii, 2(0.1%) Culex inatomii. The monthly abundance of mosquitoes from July through September showed the highest values. Although it was a general mosquito monitoring study, this study could provide a base for securing the statistical data on spreading epidemic diseases by people infected outside Korea.

• 한국대기환경학회지
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• 제9권4호
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• pp.303-309
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• 1993

An observational study of urban heat island was carried out using field data obatined during 6 days in May and August 1992 in Chunchon(population size 180.000). Air temperature was measured at 64 points along two sampling ruoutes by themisters attached to cars. Both routes cover urban and rural area and across the cneter of urban area. Continuous observation of air sonde was perfomed to clarify heights of nocturnal boundary layer(NBL) at the center of urban area. Surface meteorological observations were performed at both urban and rural sites. This study showed that heat island phenomena was obviously observed at the urbanized area during the night time with low wind speed. The average NBL heights exteded to about 10 meters, but varied with meteorological conditions. After sunset, the air temperature decreased with time at both sites and cooling rate at the urban site was greater than the rural site. The maximum heat island intensity was 7.5$^{\circ}$C at 21 LST, May 4. Usingthe two meteorological data sets obtained from urban and rural sites, the air pollutant concentration was calculated by Gaussian plume model which can obtain not only horizontal distribution of concentration but also vertical distribution. The result indicated that the concentration resulted from urban meteorological data set was lower than that from rural meteorological data set. It was also calculated that the air pollutant extended to higher level in urban meteorological data set than that in rural meteorological data set.

• 한국수산과학회지
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• 제49권6호
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• pp.856-861
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• 2016

This study compared the density of fish determined using three different echogram methods: the frequency-difference, time variable, and threshold modification methods. An acoustic survey was conducted off the coast of Jeju Island after sunset. Data at 38 and 120 kHz frequencies were collected using a commercial fishing vessel. As a reference point, the value of ${\Delta}MVBS_{120-38kHz}$ that distinguished fish from zooplankton using the 38 and 120 kHz frequencies was set at < 2 dB. The estimated density of fish along the survey line was 0.1-30.4, 0.1-64.3, and $0.1-51.7m^2/nmi^2$ using the frequency difference, time variable threshold, and threshold modification methods, respectively. The results of this study constitute basic research for estimating fish densities.

• 약학회지
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• 제31권6호
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• pp.361-369
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• 1987

The four azo dyes such as Amaranth (FD & C Red No. 2), Tartrazine (FD & C Yellow No. 4), sunset Yellow (FD & C Yellow No. 5) and Allura red (FD & C Red No. 40) are currently employed as a food additives in Korea. In this study, the effects of these azo dyes on the hepatic microsomal mixed function oxidase systems in Rats. (i.e., Cyt. P-450, Cyt. b$_5$, NADPH cyt. c-reductase and azo reductase) were investigated. Furthermore, to determine the relationship among the electron transport systems, each level of azo reductase, Cyt. P-450 and NADPH cyt. c-reductase was measured upon the administration of phenobarbital (known as an inducer of Cyt. P-450), 3-methylcholanthrene (Known as an inducer of Cyt. P-448), CoCl$_2$ (inhibitor on Cyt. P-450) or $CCl_4$ (inhibitor on Cyt. P-450). The results of these studies are as follows; (1) The levels of Cyt. P-450 and Cyt. b$_5$ were decreased upon the administration of these azo dyes. (2) When the level of Cyt. P-450 was decreased, the azo reductase activity was also decreased. (3) These azo dyes did not show any significant effect on the level of NADPH cyt. c-reductase. (4) The administration of 3-methylcholanthrene resulted in the elevation of azo reductase activity. The 3-methylcholanthrene may be responsible for the induction of CO-insensitive electron transport system.

• 한국환경과학회지
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• 제22권7호
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• pp.885-893
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• 2013

The purpose of this study was to analyze the effects of partial solar eclipse on 21 May 2012 in Korea on meteorological variables in Busan. 0800 LST(Local Standard Time) solar radiation was similar or lower than 0700 LST solar radiation, and sunshine duration decreased by 0.2~0.5 hours in Busan and great cities under the influence of the partial solar eclipse. Temperature drop due to the partial solar eclipse was $0.2{\sim}2.0^{\circ}C$, time taken to arrive at maximum temperature after onset of eclipse was 8~62 minutes, and time taken to arrive at minimum temperature after maximum eclipse was -9~17 minutes in Busan. Change of wind speed was negligible as partial solar eclipse occurred in the morning. Soil temperature of 5 cm was minute as well, the increase of soil temperature due to sunset was delayed by more than 1 hour.

• 한국주거학회논문집
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• 제22권3호
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• pp.93-100
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• 2011

The objective of this study is to provide basic objective data which can be utilized as an adjustment criterion for the alleviation of the limit on the number of floors of buildings by quantitatively evaluates the effect of the alleviation of the limit on the number of floors of buildings in apartment complexes on thermal environment of apartment complexes using data obtained from apartments in a class 2 general residential area. In this study, we carried out a thermal environment analysis utilizing the simulation of a virtual object area. The result is summarized as follows: The result of analyzing the entire surface temperature showed an equal decrease of surface temperature due to shadow in all scenarios and high floors showed a tendency of low surface temperature during daytime as the rate of shadow the high floors increase. This influences not only the surface temperature but also HIP and is judged to greatly contribute to the alleviation of the heat island effect. Also, the reason why HIP at high floors shows high values before sunrise and after sunset is thought to be because the concrete wall of the building maintains a high temperature during nighttime by absorbing and storing sunlight during daytime instead of reflecting it since it has low reflectance.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2015년도 추계학술대회
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• pp.388-389
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• 2015

웹보드게임 시행령이 시행된 후 웹보드 게임을 운영하던 대다수 업체의 매출은 큰 폭으로 감소하였다. 본 규제는 사행성과 환전을 막는데 큰 영향을 미친 것은 사실이나 아직도 이를 우회하는 비정상적인 이용이 발생하고 있다. 이에 본 연구에서는 웹보드 일몰 시행령을 앞두고 유지할 것인지, 변경 및 대안적 차원의 접근이 필요한 지에 대한 논의를 하며 특히 그 대안으로서의 책임게임 시스템을 활용한 비정상적인 이용자 패턴을 연구하고자 한다.

• 천문학회보
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• 제37권2호
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• pp.127.1-127.1
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• 2012

The 40.8-MHz VHF coherent scatter ionospheric radar, located in South Korea (Gyeryong, $36.18^{\circ}N$, $127.14^{\circ}E$), has been operating since December 2009 to investigate ionosphere E- and F-region field-aligned irregularities (FAIs) of mid-latitude. During the observation, we found E- and F-region FAIs appeared frequently: continuous echoes during the post-sunrise period and Quasi-Periodic (QP) echoes at nighttime for E region ; strong post-sunset and pre-sunrise FAIs for F region. The characteristics of E- and F-region FAIs are presented in terms of seasonal and local time variations of occurrence during December 2009 to August 2012. In addition, to investigate the correlation with geomagnetic activity to FAIs occurrence, we compared K-index variations to local time occurrence. It is worth to note our occurrence result since long term observation over several years in the mid-latitude has not yet been carried out.

• 태양에너지
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• 제19권4호
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• pp.81-91
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• 1999

The work presented here is a design and development of sun tracking system for the parabolic dish concentrator. Parabolic dish concentrator is mounted on azimuth and elevation tracking mechanism, and controlled to track the sun with computed and measured sun positions. Sun tracking mechanism is composed of 1/30000 speed reducer(3 stages) and 400W AC servomotor for each axis. The nominal tracking speed of each axis is ${\pm}0.6^{\circ}/sec$ and the system has a driving range of $340^{\circ}$ in azimuth and of $135^{\circ}$ in elevation. Sun tracking control system consists of sun sensor, wind speed and direction measurement system, AC servomotor position control system and personal computer as a master controller. Sun sensor detects the sun located within ${\pm}50^{\circ}$ measured from the sun sensor normal direction. Computer computes the sun position, sunrise and sunset times and controls the orientation of parabolic dish concentrator through the AC servomotor position control system. It also makes a decision of whether the system should follow the sun or not based on the information collected from sun sensor and wind speed and direction measurement system. The sun tracking system developed in this work is implemented for the experimental work and shows a good sun tracking performance.

• 한국작물학회지
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• 제26권1호
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• pp.45-50
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• 1981

Diurnal changes in leaf stomatal resistances were measured on leaf positions and both surfaces to investigate the stomatal response to irradiance in wheat, var. Chokwang and barley, var. Dongbori 1. Stomatal frequency and size were also determined to explain the control mechanism of gas exchanges in two species. The leaf diffusive resistances of two species decreased, as the sun rose, to minimum at 10 to 11 o'clock a.m. and increased gradually in the afternoon, even faster at sunset. As the adaxial irradiance increased, stomatal resistances decreased sensitively in the range of 30uEm$^{-2}$ㆍsec$^{-1}$ to 150uEm$^{-2}$ㆍsec$^{-1}$ quantum flux density. The stomatal opening of the abaxial surface began at lower irradiance and was completed earlier than the adaxial surface. The adaxial irradiances decreased in order of leaf position, flag, the 2nd, the 3rd leaf, and the stomatal resistances increased in the same order. Even under the same irradiance, the stomatal resistance of lower leaves were higher than those of upper leaves. The stomatal frequencies of lower leaves were less, but the stomatal size was greater than those of upper leaves. Consequently, the relative leaf area occupied by stomatal pores were constant among leaf positions in two species.