검색결과

검색조건
좁혀보기
검색필터
결과 내 재검색

간행물

    분야

      발행연도

      -

        검색결과 939

        362.
        2010.05 구독 인증기관·개인회원 무료
        Insect pest may move to near area to forage the food by adverse changes of their environments. Understanding these behaviors of searching the host will be helpful for further control. This study was performed to investigate the host preference and distribution of B. tabaci in a host plant when they needs. Once entered an area including hosts, B. tabaci will select a host rather than non-host and stayed for living. Dispersal within a niche (in a whole plant), B. tabaci was observed in lower part in tobacco and middle in tomato when seedlings, but they dispersed throughout the whole fully grown tomato plants with irregular inclined to the under, outer stretched leaves. Bemisia tabaci was also caught massively in yellow sticky traps in height of 30 cm above soil, and 30 cm above a plant. There was no attraction effect by flower model traps and fly catcher. When introduced with different densities (0, 10, 50, 100, 200, and 400) in square cages, the B. tabaci do damaged at the densities of 200 with mild and 400 with severe symptom on plants in two weeks and four weeks after inoculation.
        363.
        2010.04 구독 인증기관 무료, 개인회원 유료
        Gas turbines generating power operate in high temperature condition and use natural gas as fuel. For that reason, there are many cases where damage is done to the hot gas parts caused by the high temperature and many accidents occur like gas explosions, then various efforts are needed to maintain the hot gas parts and prevent accidents. It is difficult to find the root causes of damage to the hot gas parts from the gas explosion caused by gas leakage through rotor cooling air line from fuel gas heat exchanger during the shut down. To prevent gas turbine from damage, removal of gas leakage inside of gas turbine is required by purging the turbine before firing, improving the fuel gas heating system and installing alarm systems for detecting gas leakage from stop valve to turbine while the gas turbine has shut down.
        4,800원
        364.
        2010.03 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        It is necessary to develop new methods to prevent catastrophic failure of structural material in order to avoid accidents and conserve natural and energy resources. Design of intelligent materials with a self-diagnosing function to prevent fatal fracture of structural materials was achieved by smart composites consisting of carbon fiber tows or carbon powders with a small value of ultimate elongation and glass fiber tows with a large value of ultimate elongation. The changes in electrical resistance of CF-GFRP/GFRP (carbon fiber and glass fiber-reinforced plastics/glass fiber-reinforced plastics) composites increased abruptly with increasing strain, and a tremendous change was seen at the transition point where carbon fiber tows were broken. Therefore, the composites were not to monitor damage from the early stage. On the other hand, the change in electrical resistance of CP-GFRP/GFRP (carbon powder dispersed in glass fiber-reinforced plastics/glass fiber-reinforced plastics) composites increased almost linearly in proportion to strain. CP-GFRP/GFRP composites are superior to CF-GFRP/GFRP composites in terms of their capability to monitor damage by measuring change in electrical resistance from the early stage of damage. However, the former was inferior to the latter as an application because of the difficulties of mass production and high cost. A method based on monitoring damage by measuring changes in the electrical resistance of structural materials is promising for improved reliability of the material.
        4,000원
        365.
        2010.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In general, electric powered wheelchair is used for handicapped persons as a means of movement. Electric powered wheelchair is controlled via joystick, which means that seriously handicapped person as vertebra damaged person can not use the general electric powered wheelchair. In this paper, a new navigation method for an intelligent electric powered wheelchair is proposed, which is very simple to implement by using the robotic technology. Two cameras are used in the system. The one is used for detecting obstacles in front of the wheelchair, and the other is used for detecting the intention of the user by measuring the movement of the head. A series of experiments are performed to evaluate the proposed method and the experimental results show that the proposed method can be applicable to the navigation of an intelligent electric powered wheelchair for seriously handicapped person of vertebra damage.
        4,000원
        366.
        2010.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Due to the industrialization and urbanization, the transport of hazardous materials increases, which rises possibilities in occurring prospective accidents in terms of hazardous material transport as well. This study applied the model developed from the previous research to analyze the scale of damage areas from the accidents related to hazardous material accidents, as well as suggested a method to measure automatically the scale of accident including casualties and environmental damage based on the guideline which suggests the quantities of hazardous materials exposed from an accident and was defined in the study of standardization for hazardous material classification. A buffering analysis technique of Geographic Information System (GIS) was applied for that. To apply the model which evaluates the scale of population and exposure to environment on each link, rail network, zones, rail accident data, rail freight trips, and locations of rivers etc were complied as a database for GIS analysis. In conclusion, a method to measure damage areas by the types of hazardous materials was introduced using a Clip and a Special Join technique for overlay analysis.
        4,000원
        367.
        2010.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        국토의 70% 이상이 산악지인 우리나라 지형적 특성 때문에 도로가 산지을 인접해서 건설되는 것이 불가피하다. 최근 들어 온난화등의 영향으로 태풍이나 집중호우가 빈번히 발생하고 있으며 이로 인한 산지 도로의 산사태, 토석류, 상향짐투수압 등에 의한 인명, 시설물 피해도 극심하게 나타나고 있다. 본 연구에서는 이러한 산지 도로의 피해 중 상향침투수압에 의해 발생하는 포장의 틀림 현상에 대하여 고찰하였다. 산지도로 주변의 다양한 특성을 고려하기 위하여 상향침투수압에 의해 포장파손이 발생한 지역특성에 대하여 사명의 경사각, 산지표면의 보가유무, 산지 경사면 토사층의 두께, 지중 배수관의 설치 유무에 따라 상향침투수압을 산정하였다. 분석결과 상향침투수압은 현재 일반적으로 사용되고 있는 쇄석기층 위의 아스팔트포장 및 표면배수형식조건에서 5~10kPa 범위에서 발생하며, 사면경사각이 커짐에 따라 상향침투수압도 비례하여 커지는 것을 확인하였고, 사면의 표면을 보강 처리하지 않았을 경우의 상향침투수압은 작게 나타났다. 산지 경사면의 토사층의 두께는 지하수위가 산지표면까지 상승한 조건에서는 상향침투수압에 큰 영향은 없었으나, 지하수위가 산지표면까지 상승하는 것은 강우지속시간에 따라서 영향을 받는 점을 고려하면, 지중배수관의 설치는 도로 표층에 가해지는 상향침두수압을 효율적으로 감소시킬 수 있음을 확인하였다. 기층형식에 따른 상향침투수압에 대한 저항성 측면에서는 비 부착성인 쇄석기층보다 부착성인 안정처리기층이 자중이 증가하여 포장의 틀림 현상을 방지하는데 유리하다고 판단되지만 안정처리기층만으로는 상향침투수압에 견딜 수 없으므로 지중배수관 및 사면배수공법을 적용하여 사용하는 것이 바람직하다고 판단된다.
        4,000원
        368.
        2009.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study was conducted to investigate the fruit damage according to the number of released stink bugs and date of adult introduced on non-astringent persimmon. The fruit damage differed significantly by the number, date, and the source of feed for Riptortus clavatus. Damages on the fruits appeared when five bugs were released to mother branches bearing fruits. Damages to the fruits was heavy in the case that bugs were introduced in September and October, compared with in June, July and August. Persimmon fruit damage was influenced significantly by the available sources to R. clavatus, persimmon fruit alone or additional supply of kidney bean (Phaseolus vulgaris) and water. Characteristic damage symptoms by R. clavatus showed only scars on the fruit skin, without fruit dropping. Halyomorpha halys (=mista) showed significantly higher fruit damage when they were released in July, August, and September compared with other periods. Number of H. halys to the fruit also showed significant differences in fruit damages. Five H. halys in July showed 100% damaged fruits. The fruit damage by Plautia stali was not significantly different according to dates of introduction but the number of insects gave significant differences in the fruit damage ratio at the level of 1, 3, 5 bugs introduced to the mother branche bearing friuts. The damage symptoms by P. stali was fruit dropping in July and August but from September damaged fruits were found in the branches.
        4,000원
        369.
        2009.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Occurrence of Japanese gall-forming thrips, Ponticulothrips diospyrosi was surveyed from 143 orchards at 11 cities or counties in 6 provinces, Korea from 2008 to 2009. Occurrence of P. diospyrosi was not observed from Jeju (4 persimmon orchards) in Jeju-do and Wanju (12 persimmon orchards) in Jeollabuk-do. However, P. diospyrosi occurred newly in the orchards in Sanchung, Gyeongsangnam-do and in Gangreung, Gangwon-do. Rate of damaged orchards by P. diospyrosi in Gumi, Mungyeong, Sangju and Euseong in Gyeongsangbuk-do (73.3%) was higher than that of in Gyeongsangnam-do or Youngdong areas in Chungcheongbuk-do. A maximum rate of damaged trees by P. diospyrosi was 23.5% in Gumi, while the damage was lower in Sancheong and Jinju representing 0.2 and 1.6%, respectively. Rate of damaged leaves by P. diospyrosi was the highest in Sangju (0.12%). P. diospyrosi occurred between N35°07′50″ and 35°51′24″ and between E127°38′36″ to 128°53′02″. Persimmon orchards close to mountain were more damaged by P. diospyrosi. Edge parts of persimmon orchards were more damaged by P. diospyrosi than inner parts, especially in orchards close to mountain. Also, the middle and lower parts of tree canopy were more damaged by P. diospyrosi than the upper parts of canopy.
        4,000원
        370.
        2009.11 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This paper analyzes legal remedies for marine ecological damage as provided in Article 90, Section 2 of the Marine Environment Protection Law of the People’s Republic of China. In doing so, the paper examines the Tasman Sea Oil Spills Case, the first civil case in China to claim marine ecological damage involving foreign interests. The paper finds that many issues arise in practice due to the simplicity of the relevant legal provisions. The existing international treaties on marine oil pollution damage caused by ships do not cover marine ecological damage. However, domestic courts of some countries have relevant judicial practice on the matter. Hence, it is urgent to establish a set of new rules on marine ecological damage compensation in China and to specify the claimants, the scope for compensation and the measure of indemnity with the aim of providing an effective legal remedy for marine ecological damage.
        5,100원
        371.
        2009.11 구독 인증기관 무료, 개인회원 유료
        The engine backfire leading to the damage to the intake system is observed in the mixer-type LPG engines. The hot spot flowing back into the intake manifold from the engine cylinder during the valve overlap period is known to give rise to the backfire. This backfire is known to be the main cause of the abrupt stop of the vehicle leading to the accidents on the streets. In this study, the cylinder pressure buildup at the later stage of combustion due to the prolonged burning is presumed to be the main cause of the backflow leading to the backfire. This is experimentally observed by creating the engine misfire using the ill-conditioned ignition systems.
        4,000원
        373.
        2009.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        지진피해를 입은 건물의 주된 관심사는 건물에 남아 있는 내진성능 및 여진에 대한 안전성을 판단하는데 있다. 따라서 지진피해를 입은 지역 사회의 조속한 복귀를 위해서는 건물의 잔존내진성능 평가방법을 확립해 두는 것이 필수적이다. 본 연구에서는 무보강 조적채움벽체를 갖는 RC 건물의 잔존내진성능 평가방법 개발을 주목적으로, 전형적인 학교건물을 대상으로 축력레벨을 변수로 한 실스케일, 단층 1스팬 실험체를 제작하여 정적 반복가력실험을 실시하였다. 실험 중 잔존내진성능을 판정하는데 유용한 정보 중 하나인 잔류균열폭을 상세히 측정하였다. 본 논문에서는 잔류균열폭과 잔존내진성능과의 관계에 대해서 실험적, 해석적으로 검토하고 잔존내 진성능 평가를 위한 각 손상도 레벨에 대응하는 내진성능 저감계수를 제안한다.
        4,000원
        374.
        2009.10 구독 인증기관·개인회원 무료
        Inflammatory bowel disease (IBD) is a group of chronic disorders of unknown etiology characterized by inflammation of the gastrointestinal tract. Recent data showed that the development of IBD is associated with the interplay of genetic, bacterial, and environmental factors and dysregulation of the intestinal immune system. We investigated how the gut cells were repaired after injury in Drosophila melanogaster. In this study we made D. melanogaster intestine damage model by oral feeding with variety IBD inducer such as pathogenic bacteria Serratia marcescens, Dextran Sulfate Sodium (DSS) and bleomycin, because its function is very similar with human, even though D. melanogaster has relatively simple organism. We repeated oral feeding with variety IBD inducer and got the survival rate and 50% lethal dose (LD50). After feeding with IBD inducer, we investigated the change of the intestinal stem cells, innate immune-related gene expression, and apoptosis in D. melanogaster gut. We examined the Delta, stem cell marker, staining image in the gut after feeding with DSS and S. marcescens with LD50 concentration. The Delta positive cells greatly increased in gut cells damaged by DSS or S. marcescens. This result supports the idea that intestinal gut stem cells are increased after gut cell damage and play very important role in damaged cell repair. Expression level of antimicrobial peptides was dramatically up-regulation after gut damage. As a result of TUNEL (terminal deoxynucleotidyl transferase mediated X-dUTP nick end labeling) assay, we confirmed that cell death by apoptosis was very increased in DSS feeding flies. Accordingly, we suggest that D. melanogaster is a proper IBD model organism to study how intestine damage can be repaired.
        375.
        2009.10 구독 인증기관·개인회원 무료
        An ambrosia beetle, Platypus koryoensis, is known as a major vector of Korean oak wilt disease (KOW) to Mongolian oak and it is considered as the one of the major threat to forest ecosystem health. This study was conducted to assess damage on Mongolian oak inflicted by the ambrosia beetle on the basis of entry hole density and location within the trunk. Two hundred forty Momgolian oak trees from Mt. Uam (Gyonggi-Do, Korea) and 60 from Mt. Gyebang (Gangwon-Do, Korea) were randomly selected. Initially, the damage degree on an individual tree and the diameter at breast height (DBH) were measured, and followed by the measurement of entry hole density per 148 X 210 mm2 on lower trunk (above the surface of the earth) and upper (100 cm above the surface) on each upslope and downslope. The damage degrees were divided into three classes: Ⅰ indicating healthy tree, Ⅱ tree damaged by the ambrosia beetles and Ⅲ dead tree by the KOW. As the damage class of the Mongolian oaks increased, the number of the entry holes increased regardless of locations of entry holes. The density of entry hole lower trunk was higher than that in upper trunk, showing that the ambrosia beetle preferred to attack the lower trunk on downslope. In addition, the results showed a tendency that the average DBH of the oak trees increased as the damage class increased from Ⅰ to Ⅲ. This suggests that the ambrosia beetle prefers to attack older trees. The entry hole densities on each lower and upper trunk on downslope were principal components to assess the damage degrees of the Mongolian oak.
        376.
        2009.10 구독 인증기관·개인회원 무료
        The damage of citrus fruit by yellow tea thrips, Scirtothrips dorsalis Hood, was first confirmed in 2008, and has since been one of the serious pests of citrus in Jeju. This was reported on damage symptom on tangor cultivar, Setoka (Tangor Norin No. 8) fruits cultivated in a greenhouse and the characteristic of spatial disttribution of S. dorsalis caught on yellow sticky traps was conducted in three commercial citrus orchards. The feeding habits by S. dorsalis cause rind blemishes on the navel part of fruit. The damage is characterized by being scarped and figure like covered cloud on satsum mandarine fruit, but on by a brown ring of rough russeting that occurs on navel part of Setoka fruit. The season of damage occurrence was from middle of June to late of July. There was a highly significant relationship between the average number of thrips per trap and the maximum number caught on a trap. The overall differences between the linear regression models obtained from mean-variance relationship for each surveyed fields were tested by type Ⅲ error and contrast method. The characteristic of spatial distribution of S. dorsalis was better described by Taylor's power law than Iwao's patchiness regression, and the dispersion index which is the slope (=1.72) of linear regression model showed the aggregated distribution pattern. The sequential sampling stop lines at fixed precision level of 0.20, 0.25 and 0.30 were calculated.
        377.
        2009.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In this study, a low temperature growth of high-quality carbon nanotubes on glass substrate using a local surface heating without heating damage to substrate was tried and characterized. The local joule heating was induced to only Ni/Ti metal film on glass substrate by applying voltage to the film. It was estimated that local surface joule heating method could heat the metal surface locally up to around 1200℃ by voltage control. We could successfully obtain high-quality carbon nanotubes grown at 300℃ by applying 125 V for joule heating as same as carbon nanotubes grown at 900℃.
        3,000원
        378.
        2009.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        구조물이 건전한 상태에서 진동계측을 통한 고유진동수와 감쇠율과 같은 동적특성의 분석에 대하여 국내 외적으로 많은 연구가 진행되어 왔다. 그러나 실물 구조물에 대하여 파괴 직전까지의 큰 손상 후에 진동계측을 통한 동적특성에 대한 연구는 상대적으로 매우 미약한 실정이다. 따라서 본 연구는 3층 철근콘크리트조 건물에 엑츄에이터로 하중을 주어 건물에 손상을 준 후에 손상 전 후의 진동계측을 통하여 동적특성을 파악하였다. 손상 전 후에 대한 고유진동수 및 감쇠율을 산정하였으며, 이 결과를 국외의 기존 연구와 비교하였다. 상시진동계측 및 인력가진을 통한 계측방법을 실시하였으며, 계측 전에 고유치 해석을 선행하여 계측치와 비교분석을 하였다. 120mm의 수평변위를 준 결과 구조물의 파괴 직전 손상 전 후에 장변과 단변의 고유진동수는 각각 34.3%, 33.7% 감소하였고, 감쇠율은 각각 36.5%, 19.5% 감소하였다. 기존 국외의 연구결과와의 비교를 한 결과 고층형 건물보다 강성의 변화가 크게 감소됨을 확인할 수 있었으며, 저층형 구조물에 대한 안정성 검토가 시급함을 확인할 수 있다.
        4,000원
        379.
        2009.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Cage experiments by artificial infestations with different initial densities of Frankliniella occidentalis were conducted to analyze damages and develop control thresholds of F. occidentalis on greenhouse eggplant in 2005 and on greenhouse sweet pepper in 2007. In the eggplant experiment, the infestations of F. occidentalis resulted in direct damage on fruit surface and non-marketable fruits which had several thin or thick lines or bleaching patches on the surface. F. occidentalis adults were frequently found on the flowers of eggplants, while nymphs were mainly observed on leaves. The fruit yield of eggplants was not significantly different among experimental plots with different initial density of F. occidentalis. Relationship between % non-marketable fruits among harvested fruits of eggplant and sticky trap catches of F. occidentalis (no. thrips/trap/week) at two weeks before the harvest showed a positive correlation. Using the estimated relationship, the control threshold of F. occidentalis on greenhouse eggplant was estimated at 10 adults per week at two weeks before the harvest when 5% of non-marketable fruit was applied for the gain threshold. In the experiment of sweet pepper, the direct damage by F. occidentalis was observed on the fruit surface and calyx, and the marketable grade of the damaged fruits decreased. The significant yield loss of marketable fruits was found in plots with high initial introduced-densities. There was a high relationship between thrips density and percentage of damaged fruits. Assuming 5% yield loss (non-marketable fruit) for the gain threshold, the control threshold of F. occidentalis on greenhouse sweet pepper was 4.8 adults per trap and 0.9 individuals per flower at two weeks before harvest.
        4,000원
        380.
        2009.05 구독 인증기관·개인회원 무료
        The occurrence and damage of stink bugs were monitored at South Korea from 2007 to 2008. A total of 11 stink bug species were observed in paddy field and occurrence periods of stink bugs were significantly differed by species. In occurrence period and damage of stink bug feeding in paddy field, Scotinophara lurida occurred from June, Cletus punctiger, Eysarcoris aeneus, Rhopalus maculatus, Riptortus clavatus, E. ventralis, Stenotus rubrovittatus occurred from August and Pachygrontha antennata, C. schmidti, Trigonotylus caelestialium, Paromius exiguus occurred from September. When we were classified into two region with mountain and plain area cultivated rice, generally C. puntiger population was higher in mountain area than plain area, and E. aeneus was higher in plain area than mountain area. Also, stink bug species were higher in environment condition formed with a paddy field and a waterway overgrown with weeds. Control threshold for E. aeneus in paddy field was 1-2 individuals/heading stage, and then rate of pecky rice made to 5.0% while milk stage, dough stage and yellow ripe stage made to less than 5.0%.