• 제목/요약/키워드: Environmental control behavior

검색결과 487건 처리시간 0.026초

Impacts of C60-Ionic Liquids (ILs) Interactions and IL Alkyl Chain Length on C60 Dispersion Behavior: Insights at the Molecular Level

  • Wang, Zhuang;Tang, Lili;Wang, Degao
    • Bulletin of the Korean Chemical Society
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    • 제35권9호
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    • pp.2679-2683
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    • 2014
  • Mechanisms underlying the impacts of interactions between carbon nanoparticles (CNPs) and ionic liquids (ILs) on the physicochemical behavior of CNPs need to be more full worked out. This manuscript describes a theoretical investigation at multiple levels on the interactions of fullerene $C_{60}$ with 21 imidazolium-based ILs of varying alkyl side chain lengths and anionic types and their impacts on $C_{60}$ dispersion behavior. Results show that ${\pi}$-cation interaction contributed to mechanism of the $C_{60}$-IL interaction more than ${\pi}$-anion interaction. The calculated interaction energy ($E_{INT}$) indicates that $C_{60}$ can form stable complex with each IL molecule. Moreover, the direction of charge transfer occurred from IL to $C_{60}$ during the $C_{60}$-IL interaction. Quantitative models were developed to evaluate the self-diffusion coefficient of $C_{60}$ ($D_{fullerene}$) in bulk ILs. Three interpretative molecular descriptors (heat of formation, $E_{INT}$, and charge) that describe the $C_{60}$-IL interactions and the alkyl side chain length were found to be determinants affecting $D_{fullerene}$.

대학생의 성역할정체감과 건강행위 (Sex Role Identity and Health Behavior among University Student)

  • 박은옥;박영숙
    • 여성건강간호학회지
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    • 제5권3호
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    • pp.362-378
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    • 1999
  • This study is to investigate sex role identity and health behavior among university students in Seoul, during the late of 1999. The instruments for data obtainment were KSRI of Kim(1994), and Health Style : A Self-Test provided by ODPHP National Health Information Center. These instrument were reliable, showing Cronbach $\alpha$ .98 and .77. Frequency, t-test, $x^2$-test, stepwise regression were conducted for data analysis, using SAS 6.12 program. The major findings were as follows : 1. For female student. Androgeny(34.0%)type was most common and subjects of feminity type were 28.7%. In contrast, Masculinity type(41.8%) was most prevalent. and undifferentiated type was 30.1% among male students. There were significant difference between male and female student in the type of sex role identity. 2. 89.6% of all subjects were included in risk group for exercise and physical activity, 86.4% for diet habit, 43.2% for alcohol drinking and drug use, 35.6% for stress control, 32.8% for safety behavior, 24.8% for smoking. The big health risk behavior problem of male students were smoking, drinking, diet habit, and exercise. The important health risk behavior problem were diet habit and exercise. There were significant difference in smoking, drinking, exercise between sex. 3. Analysis of the distribution by sex role identity type and health behavior revealed that subjects who were undifferentiated typed group had high risk behavior in stress control, safety, exercise, drinking. Smoking and drinking were more problematic for masculinity typed group had high risk behavior in diet and exercise. The data showed that androginy typed group had more healthy behavior, compared with other sex role identity typed group for all of health behavior. Further research is need to understand the role of sex role identity in health behavior, the variables associated with them. And sex role identity has to be considered in research and practice about health promotion.

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An effective online delay estimation method based on a simplified physical system model for real-time hybrid simulation

  • Wang, Zhen;Wu, Bin;Bursi, Oreste S.;Xu, Guoshan;Ding, Yong
    • Smart Structures and Systems
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    • 제14권6호
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    • pp.1247-1267
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    • 2014
  • Real-Time Hybrid Simulation (RTHS) is a novel approach conceived to evaluate dynamic responses of structures with parts of a structure physically tested and the remainder parts numerically modelled. In RTHS, delay estimation is often a precondition of compensation; nonetheless, system delay may vary during testing. Consequently, it is sometimes necessary to measure delay online. Along these lines, this paper proposes an online delay estimation method using least-squares algorithm based on a simplified physical system model, i.e., a pure delay multiplied by a gain reflecting amplitude errors of physical system control. Advantages and disadvantages of different delay estimation methods based on this simplified model are firstly discussed. Subsequently, it introduces the least-squares algorithm in order to render the estimator based on Taylor series more practical yet effective. As a result, relevant parameter choice results to be quite easy. Finally in order to verify performance of the proposed method, numerical simulations and RTHS with a buckling-restrained brace specimen are carried out. Relevant results show that the proposed technique is endowed with good convergence speed and accuracy, even when measurement noises and amplitude errors of actuator control are present.

친환경농산물 선택기준이 구매의도에 미치는 영향 : 소비자 태도와 신뢰의 매개, 조절효과를 중심으로 (Effects of Selection Criteria for Eco-Friendly Agricultural Products on Purchase Intention)

  • 김미송;김동환;이기황;윤명길
    • 유통과학연구
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    • 제11권12호
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    • pp.71-81
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    • 2013
  • Purpose - This study investigated the effects of consumers' selection criteria for environment-friendly agricultural products on purchase intention and the effects of consumers' attitudes and the reliability of environment-friendly agricultural products on purchase intention by using the theory of planned behavior. Subjective norms of variables of behavioral intention, attitudes toward behavior and control of the behavior were used to create selection criteria, consumers' attitudes and reliability of environment-friendly agricultural products. The study investigated the effects of consumers' selection criteria, attitudes, and reliability of environment-friendly agricultural products on purchase intention constructing models and hypotheses of mediation and moderation between selection criteria for agricultural products and purchase intention by consumers' attitudes and reliability. Research design, data, and methodology - The findings were as follows: first, consumers' selection criteria for environment-friendly agricultural products had a significantly affirmative influence upon purchase intention. Health was the most important factor of selection criteria convenience was more important than quality and familiarity was next. Consumers' attitudes and trust had a significant influence on purchase intention. Second, testing showed that consumers' attitude and trust partially mediated selection criteria: sub-factors and purchase intention were important in selection criteria. Third, testing showed that consumers' attitude and trust had a significant moderation effect between selection criteria and purchase intention. In the test of the moderation effect between sub-factors of selection criteria and purchase intention, consumers' attitude had a significantly positive influence upon health, convenience, and familiarity, and had no significant influence upon quality and purchase intention. Consumers' trust had no significant influence upon health, convenience, and quality. Results - The study provided several theoretical implications: first, an empirical analysis was undertaken with selection criteria for environmental-friendly agricultural products, consumers' attitude, and trust to investigate subjective norms, attitude toward behavior and control of behavior based on the theory of planned behavior. Second, this study investigated both the mediation effect and moderation effect of consumers' subjective norms on attitudes toward behavior, the mediating effects of perceived behavior control and changes of behavioral intention depending upon size and direction of the variables. This study also provided several practical implications. Conclusions - First, consumption of environment-friendly agricultural products did not increase despite rapid increase of production therefore, promotion of consumption and distribution was needed considering the supply and demand of the products. Second, definite standards for selection criteria were suggested to build up consumers' attitude and trust. Consumers' attitude could be improved by factors including the brand of environment-friendly agricultural products, consistent quality, solving physiological problems caused by adverse effects of environmental problems, supplementary approaches, treatment of adverse effects by eating food, and the development and supply of products in accordance with changes of lifestyle. Finally, consumers' demand for sub-factors of selection criteria could be much higher than health, convenience, and quality of the products. Therefore, a process was needed that could continuously check consumers' needs for the products. Limitations were described at the end of the study.

17$\beta$-Estradiol이 수컷 송사리의 성적 행위 및 생식능력에 미치는 영향 (Effect of 17$\beta$-Estradiol on Sexual Behavior and Reproductivity of Male Medaka (Oryzias latipes))

  • 류지성;이철우;박응로;남성숙;남규찬;류홍일;전성환;나진균;최덕일
    • Toxicological Research
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    • 제17권2호
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    • pp.139-142
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    • 2001
  • Sexual behavior and reproductivity of male fIsh were studied as an in vivo screening method of endocrine disruptors. Male medaka (Oryzias latipes) were exposed to 17$\beta$-estradiol at nominal concentrations of 2 and 20 $\mu\textrm{g}$/l for 14 days. After exposure of the chemical, sexual behavior between male medaka and normal female which were injected with prostaglandin $F_{2\alpha}$ just before the test, was analysed by using video camera for one hour. Normal control male showed courtship dancing such as following, guarding, dancing and crossing while 17$\beta$-estradiol treated male did not show any type oj courtship dancing. Furthermore, fecundity and fertility were significantly decreased in the treated group. It was suggested that analysis of sexual behavior could be a useful endpoint for the screening of the endocrine disruptors.

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Geotechnical behavior of a beta-1,3/1,6-glucan biopolymer-treated residual soil

  • Chang, Ilhan;Cho, Gye-Chun
    • Geomechanics and Engineering
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    • 제7권6호
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    • pp.633-647
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    • 2014
  • Biopolymers, polymers produced by living organisms, are used in various fields (e.g., medical, food, cosmetic, medicine) due to their beneficial properties. Recently, biopolymers have been used for control of soil erosion, stabilization of aggregate, and to enhance drilling. However, the inter-particle behavior of such polymers on soil behavior are poorly understood. In this study, an artificial biopolymer (${\beta}$-1,3/1,6-glucan) was used as an engineered soil additive for Korean residual soil (i.e., hwangtoh). The geotechnical behavior of the Korean residual soil, after treatment with ${\beta}$-1,3/1,6-glucan, were measured through a series of laboratory approaches and then analyzed. As the biopolymer content in soil increased, so did its compactibility, Atterberg limits, plasticity index, swelling index, and shear modulus. However, the treatment had no effect on the compressional stiffness of the residual soil, and the polymer induced bio-clogging of the soil's pore spaces while resulting in a decrease in hydraulic conductivity.

유비쿼터스 기반의 축사 환경관리 시스템 연구 (A Study of Ubiquitous-based Stall Management System)

  • 정태웅;안지연;이상락;구지희
    • 한국축산시설환경학회지
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    • 제20권2호
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    • pp.57-62
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    • 2014
  • It is very important, if necessary, to remotely monitor and control the body conditions and behavior of livestock as well as the environment of stall using ubiquitous ict, in order to improve the health and productivity of livestock. With the aim of developing a stall management system, this study investigated users' needs, analyzed them to design systems, developed a web-system and an app for stall management, then applied them to a test-bed. The use of the app developed will make it easy for livestock farmers to easily monitor and control environment of stall using their smartphones and allow them to take care of stall more efficiently.

Chemical Properties of Co(II) Compound Containing Endocrine Disrupter, Bis-Phenol A

  • Park, Chil-Nam
    • 한국환경과학회지
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    • 제11권2호
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    • pp.131-137
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    • 2002
  • The chemical behavior and properties on the redox state of environmental pollutant has been investigated by electrochemical methods. We carried out to measure the variations in the redox reaction of differential pulse polarogram and cyclic voltammogram. The results observed the influences on redox potential and current of various factors with temperature and pH. These were established factors as the effect of the redox reaction. It can be clearly recognized that the electrode reaction are from qusi-reversible to irreversible processes. Also, it was mixing with reaction current controlled. The bits-phenol A in the waste water was made to compound with cobalt ion and it take away from the separation into compound. The $Co(BPA)_2$ compound was not found to be dissociation in waste water. However, this compound is avery unstable(K=1.02) and for a while, it was to be a dissociation. Therefore, we believed that it was likely to a toxic substance.

급격한 저염분 노출에 따른 참돔 Pagrus major 치어의 단기 행동반응 및 내성 한계에 관한 연구 (Short-term behavioral responses and tolerance limits of red seabream Pagrus major fingerlings following sudden low salinity exposure)

  • 윤성진
    • 환경생물
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    • 제39권4호
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    • pp.495-506
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    • 2021
  • In this study, using a continuous behavior measurement technique, the short-term behavioral responses and tolerance limits of red seabream Pagrus major fingerlings to sudden exposure to low salinity in a controlled environment were observed. The activity of the fingerlings suddenly exposed to 21.4, 17.3, and 9.8 psu increased temporarily at the initial exposure to show irregular swimming behavior, but then recovered a stable activity pattern through rapid salinity adaptation. However, the organisms suddenly exposed to 7.3 and 4.3 psu could not withstand the salinity stress, and their swimming behavior was severely disturbed and all individuals died within 48 hours. The findings suggest that red seabream underwent a temporary salinity stress process at the beginning of the exposure to concentrations of 10.0 psu or higher. At these concentrations, osmotic control was possible within at least 11 hours, so stable metabolic activity was also possible. However, organisms suddenly exposed to concentrations below 5.0 psu exceeded the tolerance to low salinity and the sublethal limit. In red seabream exposed to this concentration range, severe behavioral and metabolic disturbances were observed, and death was observed due to osmotic control failure. In conclusion, a salinity range of 5.0 to 10.0 psu can be predicted to correspond to a concentration range in which the osmotic control ability of the red seabream fingerlings is lost, and sub-lethal reactions occur.