• Title/Summary/Keyword: Damage variable

Search Result 373, Processing Time 0.026 seconds

Occurrence of Pea Weevil, Bruchus pisorum Linnaeus (Coleoptera: Bruchidae) and Its Control Efficacy of Insecticides in Yeongnam District (영남지방내 완두콩바구미의 발생 및 약제방제 효과)

  • Kim, Hyun-Ju;Bae, Soon-Do;Lee, Geon-Hwi;Park, Sung-Tae;Park, Chung-Gyoo
    • Korean journal of applied entomology
    • /
    • v.46 no.1 s.145
    • /
    • pp.159-164
    • /
    • 2007
  • Pea weevil was easily observed in the flower and pod of garden pea, but not observed in soybean at various locations in Yeongnam district through 2001 to 2003. Number of pea weevil observed in pea flower was the highest at Milyang (20), followed by Yangsan (15), Sacheon (14) and Changnyong (13), and was the lowest at Pohang (3). On the other hand, number of pea weevil observed in pea pod was the highest at Tongyeong (192), followed by Changnyong (171), Sacheon (157) and Changwon (138), and was the lowest at Pohang (12) which showed simila. tendency with the result of pea flower. Number of pea weevil occurrence observed in pea pod after one and two times applications of Insecticides in pea field were different at harvest day of 30th May while were not significantly different at harvest day of 5th June. Likewise, number of pea pod damage after one and two times applications of insecticides were different at harvest day of 10th May while was not different at harvest day of 5th June. Thus, control efficacies of insecticides according to application times against pea weevil showed very high with above 95% at harvest day of 6th June while showed variable control efficacies at harvest of 30th May.

Explicit Nonlinear Finite Element Analysis for Flexural/Shear Behavior of Perfobond FRP-Concrete Composite Beam (퍼포본드 FRP-콘크리트 합성보의 휨/전단거동에 관한 외연적 비선형 유한요소해석 연구)

  • Yoo, Seung-Woon
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.21 no.11
    • /
    • pp.771-776
    • /
    • 2020
  • In this study, the flexural/shear behavior characteristics of perfobond FRP-concrete composite beams using an FRP plate with perforated webs as formwork and reinforcement are analyzed through an analytical method. Compared with the existing experimental results, we have proved its usefulness and use it in future practice. When the nonlinearity is very large in this case, the nonlinear finite element analysis by an explicit method will be effective. The concrete damage plasticity (CDP) model adopted in this study is considered to be able to adequately simulate the nonlinear behavior of concrete, and the determination of several variable factors required in the model is compared with the experimental results and values used in the study. This recommendation will require review and adjustment for more diverse cases. The effect of the perfobond of the composite beam with perforated web is considered to be somewhat effective in terms of securing the initial stiffness, but in the case of the apex, it is considered that the cross-sectional loss and the effect of improving the bonding force should be properly arranged. The contact problem, such as slipping of the FRP plate and concrete, is considered to be one of the reasons that the initial stiffness is slightly larger than the test result, and the slightly difference from the experimental results is attributed to the separation problem between concrete and FRP after the peak.

Vulnerability Assessment of Soil Loss in Farm area to Climate Change Adaption (기후변화 적응 농경지 토양유실 취약성 평가)

  • Oh, Young-Ju;Kim, Myung-Hyun;Na, Young-Eun;Hong, Sun-Hee;Paik, Woen-Ki;Yoon, Seong-Tak
    • Korean Journal of Soil Science and Fertilizer
    • /
    • v.45 no.5
    • /
    • pp.711-716
    • /
    • 2012
  • Due to the climate change in South Korea the annual total precipitation will increase by 17 percent by 2100. Rainfall is concentrated during the summer in South Korea and the landslide of farmland by heavy rain is expected to increase. Because regional torrential rains accompanied by a storm continue to cause the damage in farmland urgent establishment of adaptation plant for minimizing the damage is in need. In this study we assessed vulnerability of landslide of farmland by heavy rain for local governments. Temporal resolution is 2000 year and the future 2020 year, 2050 year, 2100 year via A1B scenario. Vulnerability of local government were evaluated by three indices such as climate exposure, sensitivity, adaptive capacity and each index is calculated by selected alternative variable. Collected data was normalized and then multiplied by weight value that was elicited in delphi investigation. Current vulnerability is concentrated in Jeju island and Gyeongsangnam-do, however, it is postulated that Kangwon-do will be vulnerable in the future. Through this study, local governments can use the data to establish adaptation plans for farmland landslide by climate change.

Histopathological changes in fingerlings of Japanese flounder, Paralichthys olivaceus, with severe scuticociliatosis (스쿠지카섬모충에 중감염된 넙치 (Paralichthys olivaceus) 치어에 대한 병리조직학적 관찰)

  • Lee, Nam-Sil;Park, Jeong-Hee;Han, Kyu-Sik;Huh, Min-Do
    • Journal of fish pathology
    • /
    • v.7 no.2
    • /
    • pp.151-160
    • /
    • 1994
  • In order to elucidate the patterns of tissue damage evoked by the scuticociliatids, eighteen fingerlings of Japanese flounder, Paralichthys olivaceus, heavily infected with an unidentified scuticociliatid were histopathologically examined. Skin layer with the underlying musculature were severely necrotized due to the infestation of the ciliates. However in the early lesions, both dermis and myofibres remained relatively intact compared with other surrounding loose connective tissues. Mild damages were found in more dense tissues. One or more scuticociliatids were recognized in the blood and lymph vessels of the loose connective tissues with or without destructive changes. Many of nerve trunks or ganglia were also parasitized with less marked histological damage in the parenchyma. Dura and its adjacent tissues in the spinal cord were severely necrotized with massive accumulation of the ciliates in subdural space. The parasitic invasion in the central nervous system was usually confined to the cortical region. In the gill, variable degenerative changes were occurred due to the invasion of the ciliates recognized in the blood vessels of branchial arches or primary filaments. From these results, it was strongly suggested that the scuticociliatids are very actively penetrated into the deep tissues mainly through the severe destruction of the loose connective tissue components and that the vascular system could play a role in the rapid distribution of the ciliates to the remote tissues or organs.

  • PDF

Characteristics of the soil loss and soil salinity of upland soil in saemangeum reclaimed land in western South Korea

  • Kim, Young Joo;Lee, Su Hwan;Ryu, Jin Hee;Oh, Yang Yeol;Lee, Jeong Tae
    • Proceedings of the Korean Society of Crop Science Conference
    • /
    • 2017.06a
    • /
    • pp.316-316
    • /
    • 2017
  • The objective of this study is to estimate quantitatively soil salinity and soil loss at upland soils in agriculture land region in Saemangeum reclaimed land on the south Korea coasts. Soil loss and soil salinity are the most critical problem at reclaimed tidal saline soil in Korea. The several thematic maps of research area such as land cover map, topographic and soil maps, together with tabular precipitation data used for soil erosion and soil salinity calculation. Meteorological data were measured directly as air temperature, wind speed, solar radiation, and precipitation. The experiment was conducted 2% sloped lysimeter ($5.0m{\times}20.0m$) with 14 treatments and it were separated by low salinity division (LSD) and high salinity division (HSD) install. The cation content in ground water increased during time course, but in the case of land surface water the content was variable, and $K^+$ was lower than that of $Na^+$ and $Mg^{2+}$. At the LSD under rainproof condition, the salinity was directly proportional to soil water content, but at the HSD the tendency was no reversed. In condition of rainproof, the amount of soil salinity was higher at the HSD than at the LSD. Positive correlation was obtained between the soil water content and available phosphorous content at the rainfall division, but there was no significance at the surface soil of the rainproof division. Sodium adsorption ratio and anion contents in soil were repressed in the order of vinyl-mulching > non-mulching > bare field. According to the result of analyzing soil loss, soil loss occurred in a vinyl-mulching, a non-mulching and a bare field in size order, and also approximately 11.2 ton/ha soil loss happened on the reclaimed land area. The average soil loss amount by the unit area takes place in a non-mulching and bare field a lot. Our results indicate that soluble salt control and soil erosion are critical at reclaimed tidal saline soil and the results can provide some useful information for deciding management plans to reduce soil loss and salt damage for stable crop production and diverse utilization or cultivation could be one of the management options to alleviate salt damage at reclaimed tidal saline soil in Korea.

  • PDF

The Climatological Characteristics of the Landfall Typhoons on North Korea (북한에 상륙한 태풍의 기후학적 특성)

  • Ahn, Suk-Hee;Kim, Baek-Jo;Park, So-Yeon;Park, Gil-Un
    • Atmosphere
    • /
    • v.20 no.3
    • /
    • pp.239-246
    • /
    • 2010
  • In this study, the climatological characteristics of the landfall typhoons on North Korea are surveyed to estimate the frequency, the intensity, the track, and their damage. The data for the period of 1951-2008 are used from both RSMC (Regional Specialized Meteorological Center) Tokyo Typhoon Center and NCEP/NCAR (National Centers for Environmental Prediction/National Center for Atmospheric Research), EM-DAT (Emergency Events Database). There are the ten highest frequencies from 1961 to 1965 and is one frequency for the period of both 1966-1979 and 1976-1980 respectively. Even if a clear trend on the frequency of typhoon is not defined, it is noticeable the intensity has been weak since the frequency of TS (Tropical Storm) decreased. In order to figure out both the characteristic of intensity and the relation between the typhoon track and the expansion of North Pacific High (NPH), Typhoon's tracks are classified into three types as follows: (I) landing on the west coast of North Korea through the mainland of China, (II) landing on the west coast of North Korea, (III) landing on a central/eastern part of the Korean peninsula through South Korea. More often than not, the characteristic of Type (I) is the case of a landfall after it becomes extratropical cyclone. Type(II) and Type(III) show a landfall as TS grade, by comparision. On the relation between the typhoon's track and the expansion of NPH analyzed, Type (I) shows the westward expansion while both Type (II) and Type (III) show the northward expansion and development of NPH. This means the intensity of a typhoon landfall on North Korea is variable depending on the development of NPH. Finally, only two cases are found among total five cases in EM-DAT, reportedly that North Korea was damaged. And therefore, the damage by the wind of Prapiroon (the $12^{th}$ typhoon, 2000) and heavy rainfall with Rusa (the $15^{th}$ typhoon, 2002) landing on North Korea was analyzed. Moreover, it is estimated both Prapiroon and Rusa have done badly damaged to North Korea as the economical losses of as much as six billion and five hundred-thousand US dollar, respectively.

Analysis of Visitor's Satisfaction Factors and Determinants in Naejangsan National Park, Korea (내장산국립공원의 탐방객 만족요인 및 예측모형 분석)

  • Kim, Dong-Pil;Baek, Jae-Bong
    • Korean Journal of Environment and Ecology
    • /
    • v.25 no.4
    • /
    • pp.614-620
    • /
    • 2011
  • The purpose of this study was to provide basic data for developing the practical park management. For this, satisfaction degree, satisfaction factors and estimated model by satisfaction variables of visitors analyzed through a questionnaire survey in Naejangsan National Park, Korea. In the evaluation of the satisfaction, variables of 'Lack of public facility'. 'Lack of use program', 'Lack of facility to stay' 'Charge of user fee, parking fee' and 'Exorbitant pay' at Naejangsan park office and 'Charge of user fee, parking fee', 'Lack of use program' and 'Lack of facility to stay' at Baekam park office was more unsatisfied than any other variable. Satisfaction factors by Factor Analysis were loaded with 'Facility management' at Naejangsan park office(34.3%) and 'user management' at Baekam park office(45.6%) by the highest contribution degree. In estimated model of satisfaction by Multiple Regression Analysis showed in order of 'damage of trail', 'Lack of commercial facility', and 'Littering problem' at Naejangsan park office and 'damage of cultural and historic resource', 'Lack of commercial facility', 'Touting' at Baekam park office. So, Naejangsan National Park needed intensive management policy and institutional apparatus for facility management and user education.

Crack Source location Technique for nam Concrete Beam using Acoustic Emission (음향방출을 이용한 무근콘크리트 보의 균열 발생원 탐사기법)

  • 한상훈;이웅종;조홍동;김동규
    • Journal of the Korea Concrete Institute
    • /
    • v.13 no.2
    • /
    • pp.107-113
    • /
    • 2001
  • This study was conducted preliminarily to develop the crack source location technique for plain concrete beam using acoustic emission(AE). Before the main experiment, the test of virtual An source location was achieved in plain concrete block. The sensor layout was mutually compared between triangular layout and rectangular layout. As the results of test, AE source location by triangular layout was evaluated more effective than that by rectangular layout. The specimen to apply he source location technique was man in total nine specimens (each three in 40 %, 50%, 60% of W/C ratio) which the experiment variable was the compressive strength level(W/C ratio). The bending loading method is selected by cyclic loadings to evaluate the degree of concrete damage. It is seen that Kaiser effect and Felicity effect exists through analysis of AE parameters in coming failure experiment. As a result of analyzing the felicity ratio(FR) values, it is shown that this values can be used for evaluating the degree of concerto damage. AE activity is started highly at the 70% of failure load without the compressive strength level. Thus considered by a index in constructing the system of the failure warning at application of the field structure. And the results compared the real cracking location with the source location has perceived by AE monitoring before it is appeared the primary crack by visual observation.

Pathways to homelessness: The case of young adults in Korea (남성 청년의 노숙진입 시기에 따른 노숙 경로)

  • Kim, Soyoung
    • Korean Journal of Social Welfare Studies
    • /
    • v.47 no.4
    • /
    • pp.151-181
    • /
    • 2016
  • The objective of the study is to identify the sub-path of entry into homelessness of young men and enhance understanding them. In specific, homeless risk factors were extracted through their experiences, and based on which the entry paths into homelessness were drawn. The homeless young adults were divided into two groups of those who became homeless in their adolescence and those who entered into homelessness after 19 and their differences were analyzed. As a results, the most prominent differences between the two sub-groups included individual and social factors; most of those who entered homelessness after 19 had physical or psychological problems, while the other group showed delinquency factors in adolescence and adulthood. As for social factors, the former group experienced more financial damage in the process of achieving independence before being homeless, while the latter group had relatively more experience of physical and psychological damage such as bullying, harassment and violence before being homeless and financial frauds. As for investigating the causality relationship of key homeless risk factors by adding a variable of time, and based on which, a constant pattern of entry paths toward homelessness was drawn among each sub-group of homeless young adults. For policy on homelessness, it is required to develop according to the characteristics of homeless young adults. Especially, a specific approach is necessary for the different homeless pathways by sub-group. Furthermore, the study indicated that management and preemptive responses for various homeless risk factors that homeless young adults experienced throughout their lifetime could be important prevention policy against homelessness.

Effects of acute heat stress on salivary metabolites in growing pigs: an analysis using nuclear magnetic resonance-based metabolomics profiling

  • Kim, Byeonghyeon;Kim, Hye Ran;Kim, Ki Hyun;Ji, Sang Yun;Kim, Minji;Lee, Yookyung;Lee, Sung Dae;Jeong, Jin Young
    • Journal of Animal Science and Technology
    • /
    • v.63 no.2
    • /
    • pp.319-331
    • /
    • 2021
  • Heat stress (HS) causes adverse impacts on pig production and health. A potential biomarker of HS is required to predict its occurrence and thereby better manage pigs under HS. Information about the saliva metabolome in heat-stressed pigs is limited. Therefore, this study was aimed to investigate the effects of acute HS on the saliva metabolome and identify metabolites that could be used as potential biomarkers. Growing pigs (n = 6, 3 boars, and 3 gilts) were raised in a thermal neutral (TN; 25℃) environment for a 5-d adaptation period (CON). After adaptation, the pigs were first exposed to HS (30℃; HS30) and then exposed to higher HS (33℃; HS33) for 24 h. Saliva was collected after adaptation, first HS, and second HS, respectively, for metabolomic analysis using 1H-nuclear magnetic resonance spectroscopy. Four metabolites had significantly variable importance in the projection (VIP > 1; p < 0.05) different levels in TN compared to HS groups from all genders (boars and gilts). However, sex-specific characteristics affected metabolites (glutamate and leucine) by showing the opposite results, indicating that HS was less severe in females than in males. A decrease in creatine levels in males and an increase in creatine phosphate levels in females would have contributed to a protective effect from protein degradation by muscle damage. The results showed that HS led to an alteration in metabolites related to energy and protein. Protection from muscle damage may be attributed to the alteration in protein-related metabolites. However, energy-related metabolites showed opposing results according to sex-specific characteristics, such as sex hormone levels and subcutaneous fat layer. This study had shown that saliva samples could be used as a noninvasive method to evaluate heat-stressed pigs. And the results in this study could be contributed to the development of a diagnostic tool as a noninvasive biomarker for managing heat-stressed pigs.