• Title/Summary/Keyword: Poor Environment

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Molecular Weight Control of Chitosan Using Gamma Ray and Electron Beam Irradiation

  • Kim, Hyun Bin;Lee, Young Joo;Oh, Seung Hwan;Kang, Phil Hyun;Jeun, Joon Pyo
    • Journal of Radiation Industry
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    • v.7 no.1
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    • pp.51-54
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    • 2013
  • Chitosan is a useful natural polymer material in many application fields such as biomaterials, water-treatment, agriculture, medication, and food science. However, the poor solubility limits its application. In this study, the effects of radiation on chitosan were investigated using gamma ray and electron beam irradiation. The chemical structure and molecular weight analysis show similar degradation effects of chitosan powder in both gamma ray and electron beam irradiation. However, the radiation irradiated chitosan in $H_2O$ has a lower molecular weight, since the hydroxyl radicals attack the glycosidic bonds. This effect is more clearly shown in the electron beam irradiation results.

Evaluation of the Thermal Environment and Comfort in Apartment complex using Unsteady-state CFD simulation (Unsteady-state CFD 시뮬레이션을 이용한 여름철 공동주택 외부공간의 온열환경 및 쾌적성 평가)

  • Jeon, Mi-Young;Lee, Seung-Jae;Kim, Ji-Yoeng;Leigh, Seung-Bok;Kim, Taeyeon
    • KIEAE Journal
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    • v.10 no.4
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    • pp.67-73
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    • 2010
  • As more and more people desire to live in an apartment complex with a comfortable outdoor space, many construction company became interested in outdoor design. In order to increase the use of outdoor space and create the most pleasant environment, outdoor thermal environment and comfort should be evaluated quantitatively from the design stage. This study utilized ENVI-met 3.1 model to analyze outdoor thermal environment in apartment complex, and evaluated outdoor thermal comfort in 6 points of apartment complex. The physiologically equivalent temperature(PET) was employed as a outdoor thermal index. Playground B had a poor thermal environment with the maximum PET $43^{\circ}C$ (Very hot). Because shading by building and tree didn't affect outdoor thermal environment of playground B. To design comfortable outdoor space from the view point of thermal environment, the factors influencing Mean radiant temperature(MRT) and wind speed should be considered in design stage. Since it is difficult to control outdoor thermal environment compared with indoor environment, we should take into account an assessment for outdoor thermal environment and comfort in outdoor design stage.

Minimum LQI based On-demand Routing Protocol for Sensor Networks (Minimum LQI 기반의 On-demand 센서 네트워크 라우팅 프로토콜)

  • Lee, Wan-Jik;Lee, Won-You;Heo, Seok-Yeol
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.10 no.11
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    • pp.3218-3226
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    • 2009
  • A number of on-demand routing protocols for sensor networks have been proposed yet. However, the majority of proposed on-demand routing protocols for sensor networks are not suitable for a relatively poor wireless environment and sensor applications requiring reliable data transmission due to using a hop-count metric for their protocols. In this paper, we proposed a minimum LQI(Link Quality Indicator) based on-demand sensor network routing protocol that is suitable for a relatively poor wireless environment and implemented the proposed routing protocol on a TinyOS. We also compared the implemented protocol with typical hop count based routing protocol by carrying out performance experiments on a multi-hop testbed. The results from these experiments showed that the successful transmission rate of the proposed routing protocol is higher than that of typical hop count based routing protocol over a poor wireless link.

Changes in Food Companies' Product and Promotion Activities after Restriction of TV Advertising of Energy-Dense and Nutrient-Poor Foods in Korea (고열량.저영양 식품의 TV 광고 제한에 따른 식품회사의 제품 및 촉진 활동 변화)

  • Kim, Hyungjun;Yoon, Jihyun;Lee, Youngmi
    • Journal of the East Asian Society of Dietary Life
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    • v.24 no.3
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    • pp.291-300
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    • 2014
  • This study determined the effects of television (TV) advertising restriction of Energy-Dense and Nutrient-Poor Foods on product and promotion activities by food companies producing or selling children's favorite foods. A survey using a selfadministered questionnaire was conducted via on-line or fax by marketers or R&D managers from 108 food companies. The data from 55 respondents (50.9%) were analyzed. Restriction exerted positive effects on food products with respect to compliance with labeling requirements (4.0 out of 5 points) and reinforcement of nutritional contents examination of new products (3.7 out of 5 points). Reformulations of products such as reduction of nutrients like sodium, sugar and fat were also reported. In addition, food companies underwent diverse changes in promotional activities, including modification of package designs and displays in stores, offering free gifts, discounts, etc. In conclusion, restriction of TV food advertising may contribute to improvement of children's food environment by encouraging food companies to make favorable product changes. On the other hand, the results also revealed that food companies adopt diverse marketing channels that are not yet under regulation. Hence, to make policies more effective, regulation needs to be extended from TV to other marketing channels to which children are easily exposed.

Agricultural Systems for Saline Soil: The Potential Role of Livestock

  • Masters, D.G.;Norman, H.C.;Barrett-Lennard, E.G.
    • Asian-Australasian Journal of Animal Sciences
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    • v.18 no.2
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    • pp.296-300
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    • 2005
  • Human-induced soil salinity is becoming a major threat to agriculture across the world. This salinisation occurs in both irrigated and rain-fed agricultural zones with the highest proportions in the arid and semi-arid environments. Livestock can play an important role in the management and rehabilitation of this land. There are a range of plants that grow in saline soils and these have been used as animal feed. In many situations, animal production has been poor as a result of low edible biomass production, low nutritive value, depressed appetite, or a reduction in efficiency of energy use. Feeding systems are proposed that maximise the feeding value of plants growing on saline land and integrate their use with other feed resources available within mixed livestock and crop farming systems. Salt-tolerant pastures, particularly the chenopod shrubs, have moderate digestible energy and high crude protein. For this reason they represent a good supplement for poor quality pastures and crop residues. The use of salt-tolerant pasture systems not only provides feed for livestock but also may act as a bio-drain to lower saline water tables and improve the soil for growth of alternative less salt tolerant plants. In the longer term there are opportunities to identify and select more appropriate plants and animals for saline agriculture.

Efficient Energy Detection Method in Poor Radio Environment for Cognitive Radio System (Cognitive Radio 시스템을 위한 열악한 통신 환경에서 효과적인 에너지 검출방법)

  • Hyun, Young-Ju;Kim, Kyung-Seok
    • The Journal of the Korea Contents Association
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    • v.7 no.7
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    • pp.60-67
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    • 2007
  • The spectrum sensing is important for decision of using frequency band. It checks the frequency band for cognitive radio system. In this paper, we apply autocorrelation function to the energy detection method. We use the autocorrelation function to improve the performance of spectrum sensing method based on the energy detection method. This method is different from cyclostationary process method where parameters such as the mean or the autocorrelation function are time-varying periodically. And we propose improved method that is robust in poor radio environment. If the proposed method applies for sensing in the cognitive radio system, it will have the structural simplicity and the fast computation of spectrum sensing.

A Study on Health and Life Satisfaction of the Married Female Production Workers (생산직 기혼여성의 건강 및 생활만족도에 관한 연구)

  • 조희금
    • Journal of Family Resource Management and Policy Review
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    • v.2 no.1
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    • pp.167-180
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    • 1998
  • This study examines health and life satisfaction of the married female production workers(Mfpw). The data of 370 Mfpw in manufacturing sector in Taegu are collected by using questionares in August, 1995. Health scale measured by Todai Health Index is composed physical health and mental health. There are three satifsfaction areas-individual life satisfaction, family life satisfaction, and job satisfaction-in the overall life satisfaction scale. The findings of this study are as follows: 1) Mfpw’s total health conditions are poor. Especially physical health is worse than mental health. Physical health is influenced by age and purpose of attaining job, while mental health is influenced by purpose of attaining job. Mfpw who get the job for family financial needs have poor physical and mental health. 2) The overall life satisfaction level of Mfpw is lower than middle point : their family life satisfaction level is the heigest and their individual life satisfaction level is the lowest. Family income, purpose of attaining job and work place environment have effect on the level of overall life satisfaction. Mfpw who have the higher family income, get the job by non-economic motivations and work in good work place environment show the higher life satisfaction level.

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Implementation of Automatic Control Function of Tactical Communication Equipment to Wireless Communication Network Survivability Improvement (무선통신망 생존성 향상을 위한 전술 통신 장비 자동 제어 기능 구현 방안)

  • Park, Chang-Soo;Kim, Jong-Hyoun;Park, Chun-Seon;Nam, Duk-Hee;Kim, Jung-Eun
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2018.10a
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    • pp.467-469
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    • 2018
  • Tactical wireless communications often suffer from communication problems such as channel interference and communication disconnection due to the variability of the network topology and poor communication environment. Therefore, it is very important to overcome the problem of communication failure of the wireless communication network caused by the poor tactical environment and to improve the survivability. This paper describes the automatic control methodology of wireless communication equipment to identify and distinguish the situation of communication failure without user intervention and to implement more effective solution.

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A Study on the Reformation Plan for School Facilities in Depressed Downtown Area - Mixed Use Rebuilding Plan for Elementary School Facilities in Jang-Ryang and Joong-Ang Dong Areas in Pohang, Kyoungsangbukdo - (낙후 도심지역의 교육시설 재구성을 위한 연구 - 경북 포항시 장량.중앙지구 초등학교시설 복합화 방안 -)

  • Yoo, Seung-Ae;Lee, Dae-Jun
    • Journal of the Korean Institute of Educational Facilities
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    • v.14 no.3
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    • pp.36-46
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    • 2007
  • This study is based on the need to reform mixed use plan of school facilities considering the characteristics of depressed downtown area. It started with the object to make a plan by deducting function of place required and corresponded to the characteristics of depressed downtown area in Pohang city. As the result of researching present status and the characteristics of six elementary schools in Pohang which the number of student has decreased, it is found that they are required to have change in the region of depressed downtown area which have fallen behind and obsolete school facilities which idle classrooms have increased and to have reformations of a city are characterized by 5 types as poor life environment, lack of cultural facilities as community institution, poor open-space and ecological environment, non-activation of conventional market and contraction of commerce industry by outflow of industry, transfer of administration operation function and etc. and the region of school under researching shows these characteristics. I planed the mixed use program with factors of local community facility, status of school facility use and depressed area's characteristics. Finally, I propose the mixed use plan of school facilities as the strong point of sustainable development which influences on and be influenced by regional characteristics and structure of city.

Study on risk reduction method in forestry using in-depth analysis (임업 안전사고 심층분석을 통한 재해 저감 방안에 관한 연구)

  • Nam, Ki-Hun;Cho, Koo-Hyun;Kim, Kwang-Il
    • Journal of the Korean Society of Industry Convergence
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    • v.22 no.2
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    • pp.95-103
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    • 2019
  • Safety and welfare of forestry is very poor because of poor working environment, decreasing workforce and budget, and aging. These have brought many accidents and casualties. The accident rate in the field of forestry were about 2.83 times higher than average of an entire industry and mortality rate were 1.84 times higher than it. The most reason among the mortality accident was caught in, under or between objects and struck by objects. In analysis of 60 serious accident cases, the number of occurrence s of caught in, under or between objects and struck by objects were the highest. We suggest education, engineering, environment, and enforcement methods which is first aid education and emergency response system, equipment of combined IoT technologies and sensors, and certification and career program on the basis of the results.