• Title/Summary/Keyword: environment condition

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Effects of Artificially Acidified Soils on the Growth and Nutrient Status of Pinus densiflora and Quercus acutissima Seedlings (토양산성화가 소나무, 상수리나무 묘목의 생장 및 영양상태에 미치는 영향)

  • Jin, Hyun-O;Bang, Sun-Hee;Lee, Choong-Hwa;Kim, Se-young
    • Journal of Korean Society of Forest Science
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    • v.97 no.3
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    • pp.266-273
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    • 2008
  • The effects of soil acidification on the seedling growth and nutrition of Pinus densiflora and Quercus acutissima were investigated. The relationship between the seedling growth and molar (Ca+Mg+K)/Al ratio of in soil solution was examined. The results suggested that growth inhibition of seedling Pinus densiflora and Quercus acutissima was due to the low pH of soil solution, which was followed by leach of Al into soil solution, and decrease of essential elements, such as Ca in aerial pant of the seeding caused by the increase of Al concentration in subterranean pant of the seedlings. The level of growth inhibition was determined not only by Al concentration, but also by the balance of inorganic elements, Al, Ca, Mg and K. The growths of two species in total dry weight were clearly inhibited when molar (Ca+Mg+K)/Al ratio of the soil was lower than 6.0. The growth in dry weight, in the condition of the molar ratio was 0.8, was decreased 60% or 50% for the seedling of Pinus densiflora or Quercus acutissima respectively. It was concluded that the molar (Ca+Mg+K)/ Al ratio could be an important index for evaluation of the effects of soil acidification, due to acid deposition such as acid rain, on growth of trees and nutrition. And it might be a more useful indicator for evaluation of critical load of acid deposition on forest ecosystems.

Lipid Metabolism and Peroxidation in Broiler Chicks under Chronic Heat Stress

  • Shim, K.S.;Hwang, K.T.;Son, M.W.;Park, Garng H.
    • Asian-Australasian Journal of Animal Sciences
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    • v.19 no.8
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    • pp.1206-1211
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    • 2006
  • The effects of taurine supplementation on growth performance, serum and liver concentrations of lipid, fatty acid composition and lipid peroxidation in the livers of broilers under chronic heat exposure conditions were investigated. The chicks with a similar body weight were equally assigned to one of three controlled-environment chambers. The brolier chicks, which were kept at $34^{\circ}C$ were fed either with a control diet or the control diet supplemented with 0.8% taurine, whereas broiler chicks kept at $22^{\circ}C$ were fed a control diet. Both of the BW and BW gains of broilers maintained at a temperature of $34^{\circ}C$ were significantly lower than those of the control group, which was maintained at a temperature of $22^{\circ}C$ (p<0.05). However, taurine addition in the diet of birds submitted to heat stress siginficantly improved BW gain (p<0.05). The feed intake of chicks declined with increases in temperature. The relative liver and gall bladder weights of chicks fed the control diet and maintained at $34^{\circ}C$ were significantly lower than those measured in the control birds (p<0.05). However, dietary taurine was found to compensate for these reductions in liver and gall bladder weights. Relative weights of abdominal fat did not differ significantly among the three groups. Serum triglyceride concentrations were significantly lower in the chicks fed the control diet and maintained at $34^{\circ}C$ compare to those measured in the chicks fed the control diet at $22^{\circ}C$ (p<0.05). Heat stress resulted in a significant reduction in total lipid and triglyceride levels, but also increased the levels of total cholesterol in the liver (p<0.05). However, dietary taurine supplementation under the heat stress condition resulted in the recovery, to control levels, of serum triglyceride concentrations, as well as the amounts of total lipids, triglycerides, and cholesterol in the liver. The livers of chicks fed on taurine diets at $34^{\circ}C$ showed significantly higher proportions of C14:0, C16:1, C18:1, C18:2, and 20:3, and lower C18:0 and C20:4 proportions than those of chicks fed on control diets at the same temperature (p<0.05). The total levels of saturated fatty acids decreased, but monounsaturated fatty acids and unsaturated fatty acid levels increased in chicks fed the taurine diet, as compared to chicks fed the control diet at $34^{\circ}C$ (p<0.05). Peroxidizability indices were significantly lower in the heat-exposed chicks fed the taurine diet than in the non-taurine heat-exposed groups (p<0.05). In conclusion, dietary taurine results in an increase in the growth performances of chicks under heat stress conditions via improvements in lipid absorption and metabolism, as well as an induced reduction in lipid peroxidation.

Effect of Graded Levels of Green Grass Supplementation on Nutrient Digestibility, Rumen Fermentation and Microbial Nitrogen Production in Cattle Fed Rice Straw Alone

  • Chowdhury, S.A.;Huque, K.S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.10 no.5
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    • pp.460-470
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    • 1997
  • On an absolute straw diet, the effect of graded levels of green grass supplementation on intake, nutrient digestibility, rumen fermentation pattern and microbial N yield has been studied in cattle. Of the two trials conducted, 16 intact growing bulls of 304 kg weight and 32 months old, randomly allocated to four treatments in a completely randomized design in the 1st trial. While, in the, 2nd trial, four rumen cannulated local bulls of about 60 months old and 400 kg weight were used in a $4{\times}4$ Latin square design with four treatments in four periods. In both the trials, in addition to a mineral mixture, animals were supplemented with graded levels of naturally grown green grass of 0 kg (T1), 2 kg (T2), 4 kg (T3) or 6 kg (T4) to an ad libitum rice straw diet In the 1st trial, measurements were made on intake digestibility, growth rate, N balance and microbial N yield. While in the 2nd trial, in addition to the above parameters (except growth rate), rumen parameters were also studied. All levels of grass supplementation decreased the straw DM intake and increased the substitution rate. The rumen $NH_3-N$ concentration increased with the increase in grass level and ranges from 8-46 mg/l. The rumen pH and the rate and extent of DM degradability of straw were not affeceted by different rumen environments created by different levels of grass inclusion. At 48 h, straw DM degradability were 42, 44, 44 and 43% respectively for 0, 2, 4 and 6 kg grass supplementation daily. The whole gut digestibilities of DM, OM and ADF increased significantly (p < 0.05) only at 6 kg level daily. The microbial N yield was not affected by the levels of grass supplemented. The mean microbial N yield was 10 (SD 3.7) g/kg DOM apparently fermented in the rumen. The estimated minimum N loss and thus the maintenance requirement of tissue protein was 303 mg/kg $W^{0.75}/d$. All the animals lost live weight but 6 kg grass supplementation gave positive energy and N balances. Small amount of green grass supplementation is often recommended for optimization of rumen environment of a straw diet However, under the present experimental condition, no such beneficiary effect observed up to 6 kg (26% of DM intake) level of supplementation.

A Study on the Management and Living Environment of the Group-homes for the Elderly -Focusing on Jeonju and Kwangju- (노인그룹홈의 운영과 생활환경에 관한 연구 -전주시와 광주시를 중심으로-)

  • Ahn, Kyung-Ohn
    • Korean Journal of Human Ecology
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    • v.18 no.4
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    • pp.841-855
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    • 2009
  • The main objective of this study is to examine the situations of group-homes for the elderly and clarify the problems of them. This study investigates the present conditions of welfare facilities and supply conditions. 4 group-homes were surveyed in Jeonju and Kwangju cities. Data was collected through various ways including the survey conducted by facility operators, the measurement of living space, and photo-takings. The major results of this study are as follows: 1) With the introduction of nursing care insurance in 2008, the increase of the demand and supply to group-home will be expected, due to less cost for recuperation. The care of elderly in homelike atmosphere is effective to the elderly suffering from dementia. Therefore, it is proper that the supply of group-homes for dementia will be needed. 2) Group-homes for the elderly are being supplied under the standards of welfare facilities in the present. Separate supply standards, however, are needed because they are not suitable for small scale group-homes. 3) To supply Group-homes for the elderly on a one-unit basis would cause various problems such as economical unreality, personnel distribution and so on. It is necessary to supply more than two units for more efficient management. 4) The management of group-homes for the elderly is financially unstable because the operating funds heavily depend on the users or people who are connected with the facilities through private networks. Therefore, additional support is needed to settle the financial problem. It would be helpful to build the public networking that provides information about the group-home for the elderly for the public. 5) In case of the increase in the supply of the group-home in a residential area, it could be helpful to promote the group-home to the public. 6) The operators state that the main problems of group homes for the elderly lie in financial difficulties and the shortage of professionals and volunteers. The financial, personnel, and material support for personnel and the supervision of management are required for the transparency and effectiveness of the facility management. In addition, the closer network and cooperation system with the community is required. 7) The present living environments for group-homes for the elderly leave much room for improvement, considering the physical condition of the elderly. The more careful selections in the color, shape, material, and equipment of the facilities should be made for the convenience of the elderly users.

RSP-DS: Real Time Sequential Patterns Analysis in Data Streams (RSP-DS: 데이터 스트림에서의 실시간 순차 패턴 분석)

  • Shin Jae-Jyn;Kim Ho-Seok;Kim Kyoung-Bae;Bae Hae-Young
    • Journal of Korea Multimedia Society
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    • v.9 no.9
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    • pp.1118-1130
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    • 2006
  • Existed pattern analysis algorithms in data streams environment have researched performance improvement and effective memory usage. But when new data streams come, existed pattern analysis algorithms have to analyze patterns again and have to generate pattern tree again. This approach needs many calculations in real situation that needs real time pattern analysis. This paper proposes a method that continuously analyzes patterns of incoming data streams in real time. This method analyzes patterns fast, and thereafter obtains real time patterns by updating previously analyzed patterns. The incoming data streams are divided into several sequences based on time based window. Informations of the sequences are inputted into a hash table. When the number of the sequences are over predefined bound, patterns are analyzed from the hash table. The patterns form a pattern tree, and later created new patterns update the pattern tree. In this way, real time patterns are always maintained in the pattern tree. During pattern analysis, suffixes of both new pattern and existed pattern in the tree can be same. Then a pointer is created from the new pattern to the existed pattern. This method reduce calculation time during duplicated pattern analysis. And old patterns in the tree are deleted easily by FIFO method. The advantage of our algorithm is proved by performance comparison with existed method, MILE, in a condition that pattern is changed continuously. And we look around performance variation by changing several variable in the algorithm.

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A Study on Management Condition and Improvement of Artificial Greens in GBCS-Certified Apartments through the Post Occupancy Evaluation (POE를 통한 친환경건축물 인증 공동주택 인공환경 녹화 관리 실태 및 개선방안 연구)

  • Kim, Bo-Ram;Ahn, Tong-Mahn
    • Journal of the Korean Institute of Landscape Architecture
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    • v.40 no.6
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    • pp.1-12
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    • 2012
  • This study aims to suggest ways to improve sustainability on housing complexes. This study sampled eight housing projects in Seoul and GyeongGi-Do in Korea, which were completed in June 2007 and June 2008. Then, are retention and maintenance on "constructed greens for ecological environment" including "green structures substitutes retaining walls", "green roofs", and "green walls." Study methods are field investigations of the sampled sites, and Post Occupancy Analysis. Major findings were; 1) "constructed greens" are not well retained in more sites and and this implies the GBCS(Green Building Certification System) does not meet its objectives well, 2) User showed lower user satisfaction to "constructed greens". User satisfaction concerning "green structures substitute retaining walls" was higher than the satisfaction on the other constructed green type. Satisfaction Assessment Criteria lower 1han average were "level of quality", "meet the design objectives", "vegetation management status", "vegetation maintenance". 3) User satisfaction was strongly correlated on the level of quality factor of "constructed green". In addition, tue other factors are the significant correlations between the satisfactions. The present GBCS has inadequate assessment standards for maintenance, which lead to lower the entire satisfaction. Therefore, periodic recertification system, education and information providing for the managing personals, and incentives for good maintenance or disincentive for poor maintenance of the "constructed greens" are suggested to improve the GBCS.

A Study on the Selection of Evaluation Index of Biotopes in Korea (한국 비오톱 평가지표의 선정 실태)

  • Kim, Young-Sun;Oh, Koo-Kyoon
    • Journal of the Korean Institute of Landscape Architecture
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    • v.41 no.2
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    • pp.27-37
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    • 2013
  • The purpose of this research is to identify the selection status of the evaluation index in Korea and suggest improvements. In order to do so, comparison and analysis are conducted of terms, items and measures for biotope evaluation indexes attested in related documents published in domestic and foreign areas. The findings of this research are listed in the following. First, terms about biotope evaluation indexes are used and integrated with each other. Second, items used to denote biotope evaluation indexes are largely different in each region since comprehensive concepts have not been established for selecting the items. Third, there are poor grounds for items denoting biotope evaluation indexes to the species of creatures. Fourth, the items cannot provide satisfying explanations for the relative values of the current condition in the urban ecosystem of a specific region. The results of this research may be applied to provide basic materials about what is to be improved for selecting biotope evaluation indexes in Korea. In order to systematically preserve an urban ecosystem environment in Korea for the future, it is necessary for the state to develop and set up such evaluation indexes and guidelines that reflect the relative values of biotopes in each level of urban areas in Korea.

Performance Evaluation of Magnesium Bipolar Plate in Lightweight PEM Fuel Cell Stack for UAV (무인기용 경량 PEM 연료전지 스택용 마그네슘 분리판의 성능평가)

  • Park, To-Soon;Oh, Ji-Hyun;Ryu, Tae-Kyu;Kwon, Se-Jin
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.41 no.10
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    • pp.788-795
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    • 2013
  • A magnesium bipolar plate whose surface was protected by thinly deposited silver layer was investigated as an alternative to existing graphite bipolar plate of PEM fuel cells. Thin silver layer of $3{\mu}m$ was deposited on a magnesium alloy substrate by physical vapor deposition (PVD) method in an environment of $180^{\circ}C$. A number of tests were conducted on the fabricated magnesium based bipolar plates to determine their suitability for use in PEM fuel cell stacks. The test on corrosion resistance in the same pH condition as in a PEM operation demonstrated the layer protected the magnesium alloy substrate, while unprotected substrate suffered from severe corrosion. The contact resistance of the fabricated bipolar plate was less than $20m{\Omega}-cm^2$ which was superior to the conventional bipolar plates. A single cell was constructed using the fabricated bipolar plates and power output was measured. Due to the enhanced conductivity caused by low contact resistance, slight increase was observed in current density and output voltage. With low density of the magnesium substrate and ease on machining, the weight reduction of the stack of 30~40 % is possible to produce the same power output.

A Study on the Appropriateness Evaluation of Utilization of green buffer zone - Focusing on green buffer zone, Daejeon City Seo-gu (완충녹지 활용의 적정성 평가 -대전시 서구 완충녹지를 대상으로)

  • Kim, Sun Min;Lee, Shi Young
    • Land and Housing Review
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    • v.10 no.4
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    • pp.41-50
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    • 2019
  • This study was started to study the buffer zone of Daejeon metropolitan city in order to study the policy and environment for the suitability evaluation of the use of green buffer zone. The target of the study was selected as the buffer zone of western buffer, which is frequently used in the Daejeon Metropolitan City, and a preliminary index was selected to evaluate the suitability of the green buffer zone. AHP analysis was conducted to increase the reliability of the preliminary indicators and the weight was analyzed by questionnaires to experts and practitioners. In addition, based on the existing statistical data, we rebuilt the green buffer zone and investigated the current condition, and compared and analyzed the green buffer zone and the places where they did not. The results are as follow. First, unlike the statute interpretation that construction can not be done in buffered green spaces, green buffer zones have been utilized in various ways. However, the lack of advanced citizen consciousness of the residents, the responsibility of the responsible person, and the problem of the management office alone are causing problems. Second, according to the results of AHP questionnaire analysis, functional and stability among the appropriateness indexes of green buffer zone utilization were evaluated highly. Park accessibility and utilization potential also weighed somewhat, and it was judged that the epochal trend was more important in the use of green buffer zones. Third, analysis of the status of Western green buffer zones in Daejeon showed that the utilization rate was more than half. This suggests the necessity of judging the appropriateness of the application of the green buffer zone effectively due to the change of the perception of the green buffer zone of the residents. Fourth, as a result of comparing and analyzing the site where the site is used and the site where it is not, it is found that it is used within a range that does not greatly affect each index. However, as the stability has decreased, we have decided that the utilization method is most damaging to the green zone, and we should strive to improve the stability in future. Finally, the analysis of a red clay road and a red clay road sites decreased from Class I of stability to Grade II. However, the fall figure showed a difference between the 13 % drop rate of the target location and the 5% decline rate of utilization. The difference was analyzed as the difference of width of a red clay road. This can be regarded as one of the ways of damaging the green zone to the minimum extent, which is a great advantage in selecting the future utilization plan.

Simulation on Concentration of CH4 Using Hollow Fiber Membrane Permeator with Countercurrent Flow (향류 흐름 중공사 분리막의 메탄 농축 수치해석)

  • Seo, Yeonhee;Lee, Seungmin;Park, Sungeun;Jung, Woojin;Kim, Jeonghoon;Lee, Yongtaek
    • Membrane Journal
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    • v.24 no.3
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    • pp.223-230
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    • 2014
  • A numerical analysis was performed for concentration of methane from the biogas using a polysulfone hollow fiber membrane permeator. Governing equations were derived for the countercurrent flow and numerically solved by using the Compaq Visual Fortran 6.6 software. When the methane mole fraction of feed was 0.5, the mole fraction of retentate increased from 0.5 to 0.8; the normalized retentate flow rate to the feed flow rate decreased from 1.0 to 0.57 at the given typical operating condition as the feed gas flowed from the inlet to the outlet of the membrane. As the methane mole fraction of feed was changed to 0.9, the methane mole fraction of retentate became 0.93 and the normalized retentate flow rate was changed to 0.91. When the pressure ratio of the permeate to the feed was varied from 0.33 to 0.17, there was a little difference in the methane mole fraction of retentate for the low stage cut of 0.1, whereas there was an significant increment for the high stage cut of 0.3. The retentate methane mole fraction remained relatively high despite the change of a stage cut as the area of the membrane increased from $1.14m^2$ to $2.57m^2$.