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A Study on Psychological Responses and Evaluation of Degree of Satisfaction for Drivers to Traffic Informations Using Driving Simulator (차량시뮬레이터를 이용한 교통정보제공 유형에 따른 이용자 심리적 반응 및 만족도 평가에 관한 연구)

  • Hong, Ji Yeon;Lim, Joon Bum;Song, Byung Kun;Lee, Soo Beom
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.31 no.2D
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    • pp.227-235
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    • 2011
  • At present, the characteristics of drivers are not properly considered when informations are provided via VMS even though the Variable Message Signs(VMS) are one of the key information provision medias on the roads. In this study, the driver's psychological response(stress index) was evaluated using a driving simulator for the position of the VMS provided, the contents of the VMS provided, the size of characters on VMS, and types of VMS expression. It was appeared that the stress is the least when the position of the VMS provided 1.5km proceeded from exit, the contents of the VMS provided are time information and types of VMS expression are character form respectively and the size of characters on VMS is appeared not important. In addition, the change of the users' satisfaction level was measured when increasing the numbers of VMS on unit distance and the size of characters. The size of character was almost not effected in similar to the result of stress index and the satisfaction level increased when increasing the number of VMS on the unit distance. The results of this research can be utilized as basic data for the ITS system design and operation stages.

Study of Pro-environmental Development for Golf Course in Korea (한국 골프장의 친환경적 개발에 관한 연구)

  • 김광두
    • Asian Journal of Turfgrass Science
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    • v.12 no.1
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    • pp.49-78
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    • 1998
  • Nowadays, there are increasing demands of golf courses and it is necessary to make more golf courses than the present. To do this, we need to improve the environmental problems with the regional inhabitants, and it is said that the first thing to be considered in developing any golf course in Korea is to preserve the environment. In this context, the purpose of this study is to set forth several design factors to lessen the negative impacts which are accompanied with the development of golf courses. 1. The present conditions of golf courses in Korea Many new golf courses have come into being, particularly since the late 1980s, and now, in the year of 1997, over one hundred of golf courses are doing their business, yet the number of golf course is still less than required. So far, over a half of them have been made in the vicinity of Seoul on account of various reasons, and this has adversely affected on our natural environment. This unreasonable development of golf courses has caused serious water pollution, landslides and the other problems. Also, the topography of Korea is not good for golf courses. Although the demands of golf courses are increasing, the suitable sites for them are very limited, and therefore it is sometimes unavoidable to make golf courses on steep hills. Consequently, in designing golf courses in Korea, the most important thing is the balance between natural environment and artificial environment. 2.Eco-friendly golf course design factors 1) The concept of eco-friendly golf courses Ecologically sustainable and sound golf courses which are made by eco-friendly approaches 2)Basic conditions of eco-friendly golf courses (1)The most suitable sites (2) Conservation of existing ground as much as possible (3)Proper use of agricultural chemicals which have great impacts on the environment (4) Reasonable use of fertilizers (5) Developing a specialized fertilizer only for grass (6) Adaptation of organic agriculture (7) Improvement of grass sorts (8) Establishing reservoirs for purifying the water from golf courses 3) Eco-friendly golf courses (1) Location-Enough area /Gentle slope/Winding ground/Including lakes or streams /Not crossing wind's main direction Facing south or southeast /Suitable soIl for grass /Good drainage /Low level of underground water (2)Course layout and design -Consideration about existing contours as much as possible -Adaptation of Scotish design trend -Various holes' configuration -Consideration toward surrounding landscapes -Reducing grass areas -Giving buffer zones -Adapting computer methods in the process of site analysis and design (3) Eco-friendly considerations in constructing and managing golf courses -Protection of wildlife -Reuse of existing forests and preservation of topsoil -Renovation of old-fashioned courses -Reducing grass areas -Purification of water -Standization of management -Strict regulations against chemicals -Recycling organic materials -Through separation of the water inside golf courses and out of bounds -Getting proper construction works done in a due time 4.Eco-friendly considerations from a viewpoint of cultural environment 1) Well-matched landscape design and events planning 2) Implement of identifications and awarding systerns 3)Acknowledgement of superintendents' qualitications in the maintenance of golf courses 4)Increasing public golf courses and keeping good relationships with the neighbors near golf courses Key words: Pro-environmental development, Golf course.

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A new meaning of the concept, 'Sijo-samjang(시조삼장)' ('시조삼장'의 새로운 이해)

  • Kwon Soon-Hoi
    • Sijohaknonchong
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    • v.20
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    • pp.197-215
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    • 2004
  • In this paper, I reexamined the word 'Sijo-samjang(시조삼강)' and gave a new meaning of it. In addition, I proposed the new concept of 'Sijo-samjang' which meant the characteristic of a Pyon'ga(편가) in Sijo-chang(시조창). For a long time, 'Sijo-samjang' was regarded as a word which indicated the three sections of a Sijo. It was because of the fixed idea that a Sijo was always composed of a form separated by three parts. Unlike the fixed idea, I found the fact that 'Sijo-samjang' meant singing successively three different Sijos which adapted three different music by reexamining the actual uses of the word in the texts of the days. Thus, I could come to a conclusion that 'Sijo-samjang' was the word indicating a specific music system of a Sijo-chang(singing a Sijo) corresponding to a Pyon'ga of a Gagok(가곡). 'Sijo-samjang' seemed to be molded up while the music of Sijo-chang developed. Usually, a successive singing of the three different Sijos, such as Pyong-sijo(평시조), Chirum-sijo(지름시조), and Sasol-sijo(사설시조), was called 'Sijo-samjang'. However, some of the three could be omitted, and some of it could be substituted by a derived song. This kind of a usual and a derived form seemed to be settled as an important custom of singing a Silo after the 19 century. The main point of the development of music in Sijo-chang was having the characteristic of compilation which meant singing Pyong-sijo, Chirum-sijo, and Sasol-sijo successively. 'Sijo-samjang' was the concept which explained this kind of characteristic and was one of the key words to understand the development of Sijo-chang.

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British movement of 'Science and Citizenship' during the 1930-50s and L. Hogben's Science for the Citizen (1930-50년대 영국의 '과학식민의식' 운동과 L. Hogben의 Science for the Citizen)

  • Song, Jin-Woong
    • Journal of The Korean Association For Science Education
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    • v.21 no.2
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    • pp.385-399
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    • 2001
  • In this study, the contexts and values of the movement called 'Science and Citizenship' during the 1930-50s are discussed in relation to the historical development of school science education in Britain and to the current STS movement in school science. A special attention is given to the activities and ideas of a then eminent biologist, Lancelot Hogben(1895-1975) who published a textbook-like science book, called "Science for the Citizen"(1938). From the beginning of the 20th century, there was a growing realization that British education system needed to be changed in order to provide school science teaching to a wider audience with more emphasis on the relevance, industrial and humanistic aspects of science. This was echoed by a lecture series called 'Science and Citizenship' which was reported in the School Science Review, then the only nationwide professional journal for science educators and by a group of professional scientists who had socialist ideas toward society. Hogben was one of the key member of the group and delivered the second lecture of 'Science and Citizenship', titled "Biological Instruction and education for Citizenship". Hogben's main idea, illustrated in this lecture as well as in "Science for the Citizen", was that science education should be a way of teaching citizen for promoting democratic society and to achieve that science need to be taught in more integrated, utilitarian and humanistic manners, for example by showing the usefulness, relevance, historical and democratic aspects of science. In addition, a summary of his own life and activities, the social background and socialist scientists of the time, and comparisons between 'Science and Citizenship' movement and the General Science movement in the UK as well as the progressive science education in the USA, and the STS education movement in 1980s are discussed.

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A Structural Analysis between Overseas Opening of Geospatial Information and the Promotion of Geospatial Information Industry Using the Systems Thinking (시스템 사고를 통한 지도데이터 국외개방과 공간정보 산업 활성화간 인과구조 분석)

  • Yi, Mi Sook
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.36 no.4
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    • pp.213-221
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    • 2018
  • South Korea has been reluctant to open its geospatial information overseas to ensure security as a divided country. However, this cannot continue as the domestic and international environments related to geospatial information and the industrial ecosystem of information and communication technologies have been changing dramatically. Within this context, this study aims to analyze the causal relations among relevant variables and how they change and interact with time using a systems thinking process. First, causal maps were created for the domains of national security, map-based convergence service, and corporate competition. Then, the causal maps for each domain were integrated, based on which the points for policy intervention and dominant feedback loops were identified. The analysis results showed that securing the self-sufficiency of domestic geospatial businesses is a key element to determine the whole causal map, and the variable that changes the dominant feedback loop from a vicious circle to a virtuous one is the decision to open geospatial information overseas. In this study, I found the policy leverage that is a policy intervention point that can produce a great effect with little input by building a causal map of the interactions between major variables. This study is significant in that it identified and analyzed the dominant feedback loop as to which causal structure would dominate the system in the long term. The results of this study can be used to discuss not only the impacts of map data overseas opening on the national security and geospatial information industry, but also the interactions in the future when Google or other global companies request to release the geospatial information.

Abrogation of the Circadian Nuclear Receptor REV-ERBα Exacerbates 6-Hydroxydopamine-Induced Dopaminergic Neurodegeneration

  • Kim, Jeongah;Jang, Sangwon;Choi, Mijung;Chung, Sooyoung;Choe, Youngshik;Choe, Han Kyoung;Son, Gi Hoon;Rhee, Kunsoo;Kim, Kyungjin
    • Molecules and Cells
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    • v.41 no.8
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    • pp.742-752
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    • 2018
  • Parkinson's disease (PD) is a neurodegenerative disease characterized by progressive degeneration of dopaminergic (DAergic) neurons, particularly in the substantia nigra (SN). Although circadian dysfunction has been suggested as one of the pathophysiological risk factors for PD, the exact molecular link between the circadian clock and PD remains largely unclear. We have recently demonstrated that $REV-ERB{\alpha}$, a circadian nuclear receptor, serves as a key molecular link between the circadian and DAergic systems. It competitively cooperates with NURR1, another nuclear receptor required for the optimal development and function of DA neurons, to control DAergic gene transcription. Considering our previous findings, we hypothesize that $REV-ERB{\alpha}$ may have a role in the onset and/or progression of PD. In the present study, we therefore aimed to elucidate whether genetic abrogation of $REV-ERB{\alpha}$ affects PD-related phenotypes in a mouse model of PD produced by a unilateral injection of 6-hydroxydopamine (6-OHDA) into the dorsal striatum. $REV-ERB{\alpha}$ deficiency significantly exacerbated 6-OHDA-induced motor deficits as well as DAergic neuronal loss in the vertebral midbrain including the SN and the ventral tegmental area. The exacerbated DAergic degeneration likely involves neuroinflammation-mediated neurotoxicity. The $REV-erb{\alpha}$ knockout mice showed prolonged microglial activation in the SN along with the over-production of interleukin $1{\beta}$, a pro-inflammatory cytokine, in response to 6-OHDA. In conclusion, the present study demonstrates for the first time that genetic abrogation of $REV-ERB{\alpha}$ can increase vulnerability of DAergic neurons to neurotoxic insults, such as 6-OHDA, thereby implying that its normal function may be beneficial for maintaining DAergic neuron populations during PD progression.

A Study on the Economic Efficiency of Capital Market (자본시장(資本市場)의 경제적(經濟的) 효율성(效率性)에 관한 연구(硏究))

  • Nam, Soo-Hyun
    • The Korean Journal of Financial Management
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    • v.2 no.1
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    • pp.55-75
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    • 1986
  • This article is to analyse the economic efficiency of capital market, which plays a role of resource allocation in terms of financial claims such as stock and bond. It provides various contributions to the welfare theoretical aspects of modern capital market theory. The key feature that distinguishes the theory described here from traditional welfare theory is the presence of uncertainty. Securities has time dimensions and the state and outcome of the future are really uncertain. This problem resulting from this uncertainty can be solved by complete market, but it has a weak power to explain real stock market. Capital Market is faced with the uncertainity because it is a kind of incomplete market. Individuals and firms in capital market made their consumption-investment decision by their own criteria, i. e. the maximization of expected utility form intertemporal consumption and the maximization of the market value of firm. We noted that allocative decisions that had to be made in the economy could be naturally subdivided into two groups. One set of decisions concerned the allocation of first-period resources among consumption $C_i$, investment in risky firms $I_j$, and riskless investment M. The other decisions concern the distribution among individuals of income available in the second period $Y_i(\theta)$. Corresponing to this grouping, the theoretical analysis of efficiency has also been dichotomized. The optimality of the distribution of output in the second period is distributive efficiency" and the optimality of the allocation of first-period resources is 'the efficiency of investment'. We have found in the distributive efficiency that the conditions for attainability is the same as the conditions for market optimality. The necessary and sufficient conditions for attainability or market optimality is that (1) all utility functions are such that -$\frac{{U_i}^'(Y_i)}{{U_i}^"(Y_i)}={\mu}_i+{\lambda}Y_i$-linear risk tolerance function where the coefficients ${\mu}_i$ and $\lambda$ are independent of $Y_i$, and (2) there are homogeneous expectations, i. e. ${\Large f}_i(\theta)={\Large f}(\theta)$ for every i. On the other hand, the efficiency of investment has disagreement about optimal investment level. The investment level for market rule will not generally lead to Pareto-optimal allocation of investment. This suboptimality is caused by (1)the difference of Diamond's decomposable production function and mean-variance valuation model and (2) the selection of exelusive investment or competitive investment. In conclusion, this article has made an analysis of conditions and processes of Pareto-optimal allocation of resources in capital marker and tried to connect with significant issues in modern finance.

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Power Allocation Scheme For Mobile Communication Systems Using Directional Transmission (방향성 전송을 사용하는 이동통신 시스템을 고려한 파워 할당 방안)

  • Lee, Woongsup;Jung, Bang Chul;Ban, Tae-Won
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.18 no.11
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    • pp.2621-2627
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    • 2014
  • Directional transmission is one of key technology to solve the utmost problem that current mobile communication system faces, which is explosively increasing data traffic, since directional transmission can maximize the throughput of mobile communication systems. In this work, we consider power allocation scheme for mobile communication system which utilizing directional transmission. Especially, we consider the case in which multiple users in the same sector of base station, are served at the same time by utilizing directional transmission. For this scenarios, we consider equal power allocation scheme, Water-filling based scheme and inverse SNR scheme. Moreover, we propose beam power allocation scheme whose objective is to maximize overall system throughput by taking into account interference between different directional transmissions. Moreover, we have examined the spectral efficiency and Jain's fairness index of various power allocation schemes for directional transmission by using system level simulator that has been developed in our previous work. Through simulations, it has been verified that the proposed power allocation scheme can improve the spectral efficiency of the system by 28%.

A Maximally Disjoint Multipath Routing Protocol Based on AODV in Mobile Ad Hoc Networks (모바일 애드혹 네트워크에서의 AODV 기반 치대 비중첩 다중경로 라우팅 프로토콜)

  • Kim Jungtae;Moh Sangman;Chung Ilyong
    • The KIPS Transactions:PartC
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    • v.12C no.3 s.99
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    • pp.429-436
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    • 2005
  • A mobile ad hoc network (MANET) is a collection of mobile nodes without any fixed infrastructure or my form of centralized administration such as access points and base stations. The ad hoc on-demand distance vector routing (AODV) protocol is an on-demand routing protocol for MANETs, which is one of the Internet-Drafts submitted to the Internet engineering task force (IETF) MANET working group. This paper proposes a new multipath routing protocol called maximally disjoint multipath AODV (MDAODV), which exploits maximally node- and link-disjoint paths and outperforms the conventional multipath protocol based on AODV as well as the basic AODV protocol. The key idea is to extend only route request (RREQ) message by adding source routing information and to make the destination node select two paths from multiple RREQs received for a predetermined time period. Compared to the conventional multipath routing protocol, the proposed MDAODV provides more reliable and robust routing paths and higher performance. It also makes the destination node determine the maximally node- and link-disjoint paths, reducing the overhead incurred at intermediate nodes. Our extensive simulation study shows that the proposed MDAODV outperforms the conventional multipath routing protocol based on AODV in terms of packet delivery ratio and average end-to-end delay, and reduces routing overhead.

An Efficient Feedback Collection for Multimedia Multicast (멀티미디어 멀티캐스트를 위한 효율적인 피드백 정보 수집)

  • Kung, Sang-Hwan;Kang, Min-Gyu;Koo, Yeon-Seol
    • The Transactions of the Korea Information Processing Society
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    • v.5 no.3
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    • pp.751-762
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    • 1998
  • The purpose of this study is to enhance the quality of multimedia service under the heterogeneous end-terminals and network environment by monitoring the data receiving status of the group members regularly when the sender multicasts real-time multimedia data to a group. Especially, it focuses to reduce the total number of status information responded to the sender from the receivers. Accordingly. it upgrades the sender's performance by suppressing the number of status information packets generated by the receivers. The key idea of this study starts from how we profile the activity of all the members in a group. We assume that the receiver status in the worst status, so called primary receiver, represents the status of the whole group. This means that the whole group is assumed as being degraded in performance if the primary receiver is degraded, and that the whole group is assumed as being upgraded if the primary one is upgraded. In this algorithm, the primary receiver announces its status information to the whole group prior to other receivers, ana every receiver listening to the primary and other receivers' status compares its own status with them. Accordingly, any receiver may give up the status notification in case its status is not worse than others, resulting in the reduction of unnecessary responses to the sender.

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