• 한국대기환경학회지
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• 제20권1호
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• pp.59-68
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• 2004

In this study, we investigated the concentrations of volatile organic compounds (VOC) in the ambient air of a small scale municipal waste landfill site. Seasonal sampling was carried out simultaneously at two sites, i.e. one in the center of the landfill area, and the other at a boundary site. Among 38 target VOC, toluene appeared to be the most dominant compound, followed by benzene. and xylenes. The higher levels of BTX imply that paint -containing materials and/or organic solvents are the most significant sources of the VOC in the landfill environment. Seasonal variations for the samples collected at the landfill site indicated that the VOC concentrations tend to be higher in the spring and fall season and lower in the winter season. In addition, night- time concentrations appeared to be generally higher than day-time. Such daily variation might be due to more stabilized atmosphere during the night-time. Similar patterns were also found in samples collected at a boundary site. This study demonstrated that the municipal landfill, although it is small -scaled, could be an important emission source of atmospheric VOC, particularly in the vicinities of the landfill. Thus, an appropriate control strategy is required to prevent any undesirable secondary pollutions from the environmental sanitary facilities such as landfill.

• Journal of Animal Science and Technology
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• 제57권12호
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• pp.41.1-41.4
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• 2015

Background: The present study was intended to determine the prevalence and identification of species involved causing coccidiosis in broilers rearing under traditional farming system in Mirpur, Azad Kashmir, Pakistan. For the current study, a convenient sampling technique was carried out. A total of 7814 broilers (aged 1 to 6 weeks) were submitted to the Disease Diagnostic Laboratory of Livestock and Animal husbandry Department Mirpur, Azad Kashmir. Results: From the total screened, 750 were found positive for coccidiosis representing an overall prevalence of 9.59 %. Age-wise highest prevalence (10.88 %) recorded in the middle age birds (0 to 3 week old) were found more susceptible to infection than those aged above 3 weeks. Higher prevalence (12.49 %) of coccidiosis in broilers was observed in spring as compared with 6.60 % in summer season. In this study two main coccidiosis causing species, Emeria tenella and Emeria maxima were identified on the basis of their morphological feature and habitat (caeca and intestine), However, E. tenella was dominant compared to E. maxima. Conclusion: The study provides an insight to the occurrence of Emeria species which must be taken into consideration when rearing the broilers.

• 미생물학회지
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• 제27권3호
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• pp.265-271
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• 1989

서해안의 대표적 내만인 천수만 해역에서 4계절간 분리한 세균들을 대상으로 수리학적 분류를 설시하였다. 총 48가지의 형태학적, 생리적, 생화학적 실험 결과 분리된 계절에 따라 온도에 대한 서로 다른 적응 양상을 보여 주었으며, 전체적으로 다양한 환경변화에 높은 생존 능력을 보여주였다. 각 세균을 동정한 결과 Enterobacteriaceae, Aeromonas Pseudomonas와 Vibrio 등이 우점종으로 나타났으며, 계절별로는 봄 가을에 Aeromonas가, 여름 및 겨울에는 각각 Pseudom monas 와 Enterobacteriaceae가 제l우점종임이 발견되었다 Cluster analysis 결과 젠체 세규 군집은 75%의 유사도 수1 에서 총 29개의 phenetic group으로 나뉘어졌으며 각 group별로 계절적 구분이 뚜렷하였다. 전체적으로 계절에 놔른 서로 다른 생리적 특성과 종 구성이 전반적인 생태계에의 다양성과 안정성을 높여주는 것으로 나타났다.

• 한국농공학회논문집
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• 제49권2호
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• pp.99-108
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• 2007

The purpose of this study was to investigate characteristics of concentrations of pollutants such as TN (Total Nitrogen), TP (Total Phosphorus) and COD (Chemical Oxygen Demand) in outflow from a nonpoint source dominated watershed ($6.7km^2$). Regular flow measurement and water sampling were taken at five-day intervals during two years (February 2002 to January 2004) in the Ingyeong River, a tributary of the Han River. The mean concentrations of pollutants during rainy days were significantly (p<0.05) higher than those during dry days. For dry days, the flow-weighted mean concentration (0.06 mg/L) of TP during paddy irrigation periods were higher than that (0.02 mg/L) during non-irrigation periods. The seasonal mean concentration of TN was highest in spring likely due to nitrogen fertilization, but those of TP and COD were highest in summer due to particulate phosphorus and sediment-associated organic matter caused by increased discharge. The pollutant concentrations significantly increased with discharge, suggesting that the measures to reduce the increase in the concentrations during storms are needed to control nonpoint source pollution.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1992년도 하계학술대회 논문집 B
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• pp.1179-1181
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• 1992

A discrete Pl controller is implemented easily using a micro-processor, and it can be confirmed to a adaption of a system and real time processing. In this paper, a speed controller by discrete Pl control using a IBM PC/AT(12MHz) as a micro-processor is implemented and applied to a DC servo motor. In designing the discrite Pl controller, a sampling time and a speed is accepted from key-board, and is processed the control coefficient automatically, and than calculate the gain. Therefore the speed of a DC servo motor is obtained and controlled regulaly. The designed and manufactured discrete Pl control system is experimented. The result shows the good response at the 60 RPM to 250 RPM on the load using the load-spring. The speed error is under 1% on the steady load, but nearly 2-3% on the transient load.

• 전기학회논문지
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• 제63권3호
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• pp.376-382
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• 2014

E-Actuator is an essential part of an eVGT, it receives the command from the main ECU and controls the vane. An e-Actuator failure can cause an abrupt change in engine output and it may induce an accident. Therefore, it is required to detect anomalies in the e-Actuator in real time to prevent accidents. In this paper, an e-Actuator fault detection method using on-line parameter identification is proposed. To implement on-line fault detection algorithm, many constraints are considered. The test input and sampling rate are selected considering the constraints. And new recursive system identification algorithm is proposed which reduces the memory and MCU power dramatically. The relationship between the identified parameters and real elements such as gears, spring and motor are derived. The fault detection method using the relationship is proposed. The experiments with the real broken gears show the effectiveness of the proposed algorithm. It is expected that the real time fault detection is possible and it can improve the safety of eVGT system.

• 한국의류학회지
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• 제24권8호
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• pp.1155-1166
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• 2000

The purpose of this study is to investigate deconstructive trends of the street fashion in the 1990s spring/summer(S/S) Collections. This study was carried out by both the qualitative analysis and the quantitative analysis. In the qualitative analysis, the important street fashion was grouped and deconstruction was sampling of category. In the quantitative analysis, it took frequency, percentage and $\chi$$^2$-test. The results of the quantitative analysis are as follows: 1. \"N대-Hippie/Grunge\" has been most popular street fashion through the 1990s. The next is \"Sportive Casual\". 2. According to \"deconstructive inner meanings\", there are significant differences between the S/S street fashion in the 1990s. In \"N대-Mods/Jazz\" style, \"Sportive Casual style\" and \"Technos/Cyber-punk\" style, \"Intertextuality\" is high. In \"N대-Hippie/Grunge\" style, \"Exhibition of Otherness\" is high. 3. According to the \"deconstructive outer description\", there are also significant differences between the S/S street fashion in the 1990s. But, In \"Neo-Mods/Jazz\" style, \"Not Included\" is high, which means the \"N대-Mods/Jazz\" isnt related to the \"deconstructive outer description\". In \"N대-Hippie/Grunge\" style, \"Poverty.outworn\" is high. In \"Sportive Casual\", \"Exposure\" is high. In the \"Technos/Cyber-punk\", \"Destruction.Division\" is high.

• Wind and Structures
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• 제21권6호
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• pp.625-639
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• 2015

Monopiles have been most widely used for supporting offshore wind turbines (OWTs) in shallow water areas. However, multi-member lattice-type structures such as jackets and tripods are also considered good alternatives to monopile foundations for relatively deep water areas with depth ranging from 25-50 m owing to their technical and economic feasibility. Moreover, jacket structures have been popular in the oil and gas industry for a long time. However, several unsolved technical issues still persist in the utilization of multi-member lattice-type supporting structures for OWTs; these problems include pile-soil-interaction (PSI) effects, realization of dynamically stable designs to avoid resonances, and quick and safe installation in remote areas. In this study, the effects of PSI on the dynamic properties of bottom-fixed OWTs, including monopile-, tripod- and jacket-supported OWTs, were investigated intensively. The tower and substructure were modeled using conventional beam elements with added mass, and pile foundations were modeled with beam and nonlinear spring elements. The effects of PSI on the dynamic properties of the structure were evaluated using Monte Carlo simulation considering the load amplitude, scouring depth, and the uncertainties in soil properties.

• Journal of the Korean Wood Science and Technology
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• 제48권3호
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• pp.283-290
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• 2020

For visual inspection-based wood identification, optical microscopy techniques typically require a relatively large sample size, and a scanning electron microscope requires a clean surface. These novel techniques experience limitations for objects with highly limited sampling capabilities such as important and registered wooden cultural properties. Synchrotron X-ray microtomography (SR-µCT) has been suggested as an effective alternative to avoid such limitations and various other imaging issues. In this study, four pieces of wood fragments from wooden members used in the Manseru pavilion of Bongjeongsa temple in Andong, Korea, wereused for identification. Three-dimensional microstructural images were reconstructed from these small wood samples using SR-µCT at SPring-8. From the analysis of the reconstructed images, the samples were identified as Zelkova serrata, Quercus sect. Cerris, and Pinus koraiensis. The images displayed sufficient spatial resolution to clearly observe the anatomical features of each species. In addition, the three-dimensional imaging allowed unlimited image processing.

• 한국주거학회:학술대회논문집
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• 한국주거학회 2008년 추계학술발표대회 논문집
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• pp.92-95
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• 2008

As society ages increasingly, maintaining an independent lifestyle at home becomes an important issue for older people. The elderly themselves demand an independent lifestyle despite their health status and living arrangements. The purpose of this study is to provide basic guidelines for the elderly housing through the analysis of seniors' housing behavior. The total of 438 residents take part in the questionnaire survey research through the quota sampling method grouped by age (60-64 group, 65-69 group, 70-74 group, over 75 group). The results are as follows. (1) Seniors' subjective physical and functional status is not differed one age group from the others, but it is differed by the sex. (2) Seniors spend more than three hours on watching TV. The male spend more time on information search, while the female on the house chores. (3) The older use the bedroom more than the younger. Living rooms are more frequently used among the young old and the residents live in the apartment houses. (4) More than half senior use a sofa in the living room, a table in the dining room, and a bed in the bedroom. The young old and the apartment residents use such furniture more than the other groups.