• Title/Summary/Keyword: dynamic relationship

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Impact of Enterprise R&D Investment on International Trade in Korea under the new Normal Era (뉴 노멀 시대하 한국기업의 R&D투자가 무역에 미치는 영향)

  • Kim, Seon-Jae;Lee, Young-Hwa
    • The Journal of the Korea Contents Association
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    • v.12 no.9
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    • pp.357-368
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    • 2012
  • The purpose of this study is to empirically examine the impact of enterprise R&D investment on international trade in Korea under the new Normal Era. In order to test whether the time series data of trade variables are stationary or not, we put in operation unit root test and cointegration test. Based on VECM (Vector Error Correction Model), we also apply impulse response functions and variance decomposition to estimate the dynamic effects in the short-run and long-run. The results show that the relationship between enterprise R&D investment and international trade (export and import) exists in the long-run as well as in the short-run. The results of applying impulse response functions and variance decomposition also indicate that the impact of enterprise R&D investment on international trade is positive, and a significant portion of fluctuations in the trade variable is explained by enterprise R&D investment. Therefore, enterprise R&D investment must be continuously increased to improve economic growth with promoting trading competition power in Korea under the new Normal Era.

Zooplankton Community Dynamic in Lentic Freshwater Ecosystems in the Nakdong River Basin (낙동강 유역권 내 정수생태계의 동물플랑크톤 군집 동태)

  • Kim, Seong-Ki;Hong, Dong-gyun;Kang, MeeA;Lee, Kyung-Lak;Lee, Hak Young;Joo, Gea-Jae;Choi, Jong-Yun
    • Korean Journal of Environment and Ecology
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    • v.29 no.3
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    • pp.410-420
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    • 2015
  • In order to estimate the influence of environmental factors on zooplankton communities in lentic freshwater ecosystems, 20 reservoirs and wetlands were monitored by season in 2013. A total of 109 species of zooplankton were identified during the study period. Zooplankton assemblage showed a different distribution in its density and diversity in accordance with the seasons. In particular, the density of zooplankton (98 species and 603ind. L-1) was the most in autumn when compared to the other seasons. In order to effectively analyze zooplankton distribution that are affected by various environmental factors, a Self-Organizing Map (SOM) was used, which extracts information through competitive and adaptive properties. A total of 11 variables (8 environment factors and 3 groups of zooplankton) were patterned on to the SOM. Based on a U-matrix, four clusters were identified from the model. Among zooplankton communities, rotifer displayed a positive relationship with water temperature, and cladocerans and copepod were positively related to conductivity, chlorophyll a, and nutrient factor (i. e. TN and TP). In contrast, high dissolved oxygen appeared to have a negative effect on zooplankton distribution. Consequently, the SOM results depicted a clear pattern of zooplankton density clusters partitioned by environmental factors, which play a key role in determining the seasonal distribution of zooplankton groups in lentic freshwater ecosystem.

A Study on the Sequence Analysis Technique of Urban Landscape Color and Urban Color Characteristics in accordance with Spatial Openness - Focusing on the View of the Daegu Monorail - (도시 경관색채의 시퀀스 분석기법과 공간 개방도에 따른 도시색채 특성연구 - 대구광역시 지상철 조망을 중심으로 -)

  • Koo, Min-Ah
    • Journal of the Korean Institute of Landscape Architecture
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    • v.44 no.6
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    • pp.120-136
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    • 2016
  • This study, views the color of scenery not as a static state, but rather as a continuous sequence of perceptions that incorporates the concept of time. This study derived techniques to quantitatively analyze the flow and data from this sequence. By utilizing this, urban color trends can be based on openness. This is very close to what would be experienced by an actual viewer: it extracted color data and visual amount from frames at 2-second intervals by shooting a video of the color sequence of the city as seen from both the left and right sides from the inside of the monorail (line 3 of the Daegu urban railway). These images were classified by color group, brightness, chroma, high chroma distribution derived techniques such as openness of space, brightness level, clarity level, high-chroma distribution and code, advantage of visual amount, dominant factor exposure, hot and cold color image and dynamic of sequence rhythm. During the derived sequence, the data determines the openness in the visual amount of sky and it was found that the tendency of the colors of the city was opening regression analysis. The more colorful the city is opening the brightness is lowered, the chroma increased slightly, cold colors significantly increased, which also had a very deep relationship with Lynch enclosed proportion, color change of the city trends through the actual scenery could grasp in more detail.

Physical Properties of the Silica-Reinforced Tire Tread Compounds by the Increased Amount of Vulcanization Agents (가교제 증량이 트레드용 실리카 컴파운드의 물성에 미치는 영향)

  • Seo, Byeongho;Kim, Ki-Hyun;Kim, Wonho
    • Elastomers and Composites
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    • v.48 no.3
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    • pp.201-208
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    • 2013
  • In this study, effect of different amounts of sulfur and vulcanization accelerators in the acrylonitrile styrene-butadiene rubber (AN-SBR)/silica compounds on the properties of tire tread compound were studied. As a result, cure rate and degree of cross-linking of the compounds were increased due to enhanced cross-linking reactivity by the increased amounts of sulfur and vulcanization accelerators. Also, abrasion resistance and the mechanical properties such as hardness and modulus of the compounds were improved by enhanced degree of cross-linking of the compounds. For the dynamic properties, tan ${\delta}$ value at $0^{\circ}C$ was increased due to the increase of glass transition temperature ($T_g$) by enhanced degree of cross-linking of the compound, and tan ${\delta}$ value at $60^{\circ}C$ was decreased. Initial cure time ($t_1$) showed the linear relationship with tan ${\delta}$ value at $60^{\circ}C$. This result is attributed that reduced initial cure time ($t_1$) of compounds by applying increased amount of curatives can form cross-linking in early stage of vulcanization that may suppress development of filler network. This result is verified by observation on the surface of annealed compounds using AFM (atomic force microscopy). Consequently, decreased initial cure time is considered a very important parameter to reduce tan ${\delta}$ at $60^{\circ}C$ through reduced re-agglomeration of silica particles.

A Study of the Anxiety Levels of Hospitalized Psychiatric Patients in Terms of Length of Hospitalization (정신과 입원환자의 입원기간에 따른 불안정도에 관한 연구)

  • 김윤희
    • Journal of Korean Academy of Nursing
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    • v.11 no.1
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    • pp.45-63
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    • 1981
  • This study was done to determine the relationship between the anxiety levels of hospitalized psychiatric patients and various influencing variables. The purpose of this study was to determine factors that may help hospitalized psychiatric patients to experience lower levels of anxiety in relation to changing situations and provide the basic data for a dynamic approach which is important in the field of modern psychiatric nursing that understands and analyses the meaning of patients behavior. The anxiety may produce stress, which is a common experience among all human beings. Patients may merely feel uncomfortable in the state of mild anxiety, however, the severe state could be an obstacle to treatment and recovery from disease. The anxiety of the psychiatric patient is a factor which greatly influencing the patient's behavior, so his disorderd behavior is an expression of defence or pathologically fixed behavior. According the psychiatric patient's anxiety at the time of admission is the concern of the health team. The nurse's special concern has to do with understanding and supporting the patient and meeting his individual needs by frequent close contact during the entire hospitalization period, compared to other teamembers the nurse's responsibility in this regard is greated. So this study emphasizes the necessity of creating conditions these, but above all the psychiatric nurse should create a therapeutic environment by not only regarding the patient's behavior or symptoms but understanding the meaning of them. The subjects of this study were 57 psychiatric patients selected from the K neuropsychiatric hospital located in Kunsan city. Data were collected twice from the same patients within a 24 hour period after admission and 10 days after admission. (September 18th to November 8th, 1980). The data collected method was through direct interview, and the interview time was 20 minutes for each patient. Data analysis included Item Analysis & Internal Consistency Reliability Tests, Percentages, t-test, analysis of variance and stepwise multiple regression analysis. The findings of this study were as follows. A. Test of Hypothesis a. Hypothesis 1 :“The anxiety level of psychiatric patients within 24 hours after admission will be higher than those of the same patients 10 days after admission,”was accepted. (t = 3. 15 ; p < 0.005) b. Hypothesi 2:“The more the number of admissions the higher the level of anxiety related to two categories”, was accepted. (affective anxiety: F = 5.50, p < 0.005, Somatic anxiety: F = 9.12, p <.

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An Exploratory Study on the Structural Relationships among Meaningfulness of work, Big 5 character-types and Job Stress (직무 의미감, Big 5 성격유형, 직무스트레스의 구조적 관계에 관한 탐색적 연구)

  • Baek, You-Sung
    • Management & Information Systems Review
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    • v.36 no.5
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    • pp.85-98
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    • 2017
  • The purpose of this study is to exploratory examine the structural relationships among meaningfulness of work, personality(Big 5 character-types) and job stress. To conduct such examination, the author (i) designated meaningfulness of work, personality(Big 5 character-types) and job stress as variables and (ii) designed a research model by conducting preceding studies on the variables. To examine the research model the author collected the survey data from the residents in Kyoungsangbuk-do, 332 copies of questionnaire. Collected data were analyzed using SPSS and AMOS programs. The analysis results are as follows. Especially, (1) the meaningfulness of work had a positive effect on agreeableness, conscientiousness, and extraversion. (2) the meaningfulness of work had a negative effect on neuroticism. (3) the meaningfulness of work had no effect on openness to experience. (4) the neuroticism factor had a positive effect on psychological job stress and physical job stress. (5) the openness to experience had a negative effect on psychological job stress and physical job stress. (6) the meaningfulness of work had no effect on psychological job stress and physical job stress. The implications and limitation which this study are as follows. First, this study has discovered that there was statistically significant relationship between the meaningfulness of work and Big 5 character-types. Second, Big 5 character-types(neuroticism, openness to experience) had statistically effect on psychological job stress and physical job stress. This study have limitation in that was conducted based on cross-sectional design of research. Because, the mechanism of job stress is a dynamic process.

Renaissance of Geographic Education in the United States since 1980: Its Dynamic Process and Implications to Geographic Education in Korea (1980년대 이후 美國 地理敎育 復興運動의 展開過程과 그 示唆點: 地理學, 地理敎育, 그리고 敎育政策의 關係)

  • Seo, Tae-Yeol
    • Journal of the Korean Geographical Society
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    • v.28 no.2
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    • pp.163-178
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    • 1993
  • The purpose of this paper is to provide a better understanding of the unprecedented reform movement of geographic education in the United States since 1980 and extract some implications from this movement for geographic education in Korea. For the purpose, the history to this movement was reviewed through following three stages. In the first stage(1980~1984: form :HSGP" to :"Guideline"), the voluntary improvement movement appeared at California and the orgni-zational movement began in 1982 such as the Committee on Geography and International Knowledge. The national educational refrom imperatives, presented at "A Nation at Risk", and "Back to Basics" movement provided good opportunities to resurrect geography as a basic subject. For next real resurrection movement, the very important document "Guidelines for Geographic Education" was published at 1984. In the second stage(1985~1989: from "Guide-lines" to "Public"), the "Guideline" gave power-full motives and foci for reconstructiong the contents of geography, especially by the five fundamental themes(Location, Place, Relation-ships within Places, Movement, and Region). Also GENIP as the symbol of unity of all four major geography organization(AAG, NCGE, NGS, AGS) contributed to expanding and stren-gthening geography education. Also Geography Educagtion Program of NGS was a smart and well organized program to improve geographic education through it's a five strategies: Grass-roots organization(Alliances), Teacher education, Pu-blic awareness, Educational materials develo-pment, Targeted outreach to education decision-makers. In the late 1980s, the last focus of movement was the Public awareness and Edua-ction decision-making. In the third stage(1990-present: from "Public" to "Core Subject"), the initiative pendulum swung from geography organization to nation curricu-lum. In this National Curriculum, Geography was approved as a "Core Subject" and The 1994 National Geography Assessment Framework was constructed to assess the outcome of student's education in geography in grades, 4,8, and 12. Some Implications extracted from the process and contents of renaissance movement of geogr-aphic education in the Uinted States since 1980 are as follows. First, It shows the importance of the unity and target assignment among the geography organization. Second, interactive relationship between the academic geography and school geography develops each other. Third, teacher education, including pre-service education, including pre-service education and in-service education, is a key element to improve the quality of geography. And teacher organization is a good clearing house to exchange information for good geography. Forth, the positive and active response to changes in socketies such as globalism and inter-nationalizing, national education policy, and the trend of pedagogy is needed to rejuvenate geo-graphic education. Above all, we need to establish a well organized and powerfull program, sophisticated activities strategies, and long-term implementa-tion plan if we want more and better school geography.

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Future Development of Republic of Korea NCAGS (한국형 선박통제의 발전방향에 관한 연구)

  • Kim, Sung Hae;Jung, Hyo Sup
    • Strategy21
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    • s.44
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    • pp.352-376
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    • 2018
  • Through this research, the current state of naval coordination and guidance of shipping is reviewed whereupon which a suggestion is made for a novel role which satisfies the needs of the people and the country asked of the Navy. Taking into consideration the dynamic security environment, the developing relationship between the two nations on the Korean peninsula, and the influence that the Republic of Korea has on maritime security, it is made more urgent that the Navy takes a proactive course of action in terms of naval coordination and guidance of shipping. The current form of Korean naval coordination and guidance of shipping is adapted from the logical and flexible concepts of NCAPS and NCAGS and is one of many tasks that the Republic of Korea Navy must perform. However, when the Republic of Korea Navy develops blue-water capabilities with the ambitions of protecting its people and their way of life, naval coordination and guidance of shipping could potentially become one of the primary functions of the Republic of Korea Navy that the it must champion. Already, there are indications that foreign navies are, through many developments and commitment towards naval coordination and guidance of shipping, protecting its people and states' interests wherever is necessary. In the case of Chile, its Navy has taken the helm of naval coordination and guidance of shipping and has integrated various maritime organizations including the coast guard and the National Customs Service for the sake of maintaining regional maritime security, showing immediate force if necessary. Presently, as the Republic of Korea Navy looks to be a global naval power, it is important that a reprioritization of the Navy's mission is undertaken, all the while sustaining military readiness posture on the Northern Limit Line. It cannot be any more emphasized how crucial thorough military readiness posture is as a natural stance against the enemy. That being said, contributing towards international maritime security is consistent with the nation's standing. It is a fact that maritime security has been conceptualized and developed merely as a study within the Ministry of Maritime Affairs and Fisheries, the Republic of Korea Navy, and other governmental organizations, forces, and academia. Naval cooperation and guidance of shipping suggested by this research as a practical operational field is a concrete solution to what once was an abstract concept. To stand firm on its status as a maritime nation, the Republic of Korea must establish a Maritime Security Organization within its Navy and develop the appropriate doctrines. Attaining experts, developing doctrines, and cultivating the capability to deploy maritime forces will allow for the Republic of Korea to execute a primary role in keeping international maritime security and naval coordination and guidance of shipping. To fully achieve its latent potential necessitates the Republic of Korea Navy to expedite the introduction of naval coordination and guidance of shipping concepts and to establish the appropriate doctrines, operation plans, and organizations.

A Dynamic Programming for Solving Resource Allocation Problems in Video-on-Demand Service Networks (Video-on-Demand 서비스망의 자원 할당 문제를 위한 동적계획법)

  • Cho, Myeong-Rai
    • The Transactions of the Korea Information Processing Society
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    • v.7 no.10
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    • pp.3182-3194
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    • 2000
  • It is strongly beliefed that Video on Demand(VOD) will become one of the most promising services in Broadband Integrated Services Digital Network(B-ISDN) for the nest generation VOD service can be classified into two types of services 'Near VOD(NVOD) and Interactive VOD(IVOD). For both services, some video servers should be installed at some nodes(especially, at the root node for NVOD service) in the tree structued VOD network,so that each node with video server stores video programs and distribules stored programs to customers. We consider thre kinds of cost.a program transmission cost, a program storage cost, and a video server installation cost. There exists a trade-off relationship among those three costs according to locationsl of video servers and the kinds of programs stord at each video server. Given a tree structured VOD network, and the total number of programs being served in the network, the resource allocation problem in a VOD network providing both IVOD and NVOD services is to determine where to install video servers for IVOD service, which and how many programs should be stored at each video server for both IVOD and NVOD services, so as to minunize the total cost which is the sum of three costs for both IVOD and NVOD services. In this paper we develop an efficient cynamic programming algorithm for solving the problem. We also implement the algorithm based on a service policy assumed in this paper.

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Time-Varying Effects of Oil Shocks on the Korean Economy (한국경제에 미치는 유가충격의 시간-가변적 효과에 관한 연구)

  • Cha, Kyungsoo
    • Environmental and Resource Economics Review
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    • v.27 no.3
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    • pp.495-520
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    • 2018
  • Because of structural changes in the international oil market and the economy, it is widely recognized that the impact of oil shocks on the economy has weaken since the mid-1980s. This study tries to examine the validity of the recent perception about the relationship between oils shocks and the economy, estimating the time-varying effects of oil shocks on the Korean economy. The results show that the dynamic effects of oil shocks normalized to a one standard deviation has been relatively constant, in contrast to the recent perception and a number of existing studies. In addition, because the shape of impulse response functions at each point in time spanning from 1984:II to 2017:IV has not been changed significantly, it seems that the propagation mechanism of oil shocks also has not been substantially altered. These findings indicate that even though structural changes of the economy, such as the reduction in the share of oil consumption and the spread of high-efficiency energy technologies, have been rapidly progressed, it is not still enough to offset the negative effects of oil shocks. Rather, it seems that the recent perception about the shrinking effects of oil shocks is mainly due to the assumptions that do not reflect changes in the size of oil shocks. In particular, this problem appears more pronounced in the case of the typical a one standard deviation increase oil shock under homoskedasticity assumption, which is widely adopted in the most VAR analyses. Therefore, in estimating the effects of oil shocks on the economy, it is important to specify the correct model and normalization method, to reflect changes in the size of oil shocks.