• 한국자원식물학회지
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• 제11권3호
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• pp.345-352
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• 1998

A Korean endemic and evergreen small tree ' Dendropanax morbifera $L_{EV}$.(Araliaceae)' is a component of evergreen forest and mainly idstributein sourthern region and islands in Korea. A local population of D. morbifera which is located between evergreen and deciduous forest within 50m x 50m quadrate was investigated to ascertain the change of population structure, emergence and growth dynamics of seedlings and saplings, and pattern of spatial distribution by the temproal and spatial expansion of population . The result of analysis of population structure by Importnace Value(IV), evergreen forest showed a high species diversity of evergreen tree species such as Cinnamomum japonicum, Machilus japonica, Neolitsea serica, Daphniphyllum macropodum, Ligustrum japonicum, and etc, in middle and under story than in upper story where Camelia japonica and Quercus acuta were dominant. And in conterminous deciduous fores, the major component of evergreen forest in this region, Camellia japonica, Quercus acuta, evergreen tree of Lauraceae and etc. were abundant in only under story. IV of D. morbifera differed from among three story. In comparative analysis of emergence and growth dynamics of D. morbifera seedlings and saplings between evergreen and deciduous forest, emergece and density of seedlings were significantly greater in evergreen than in deciduous forest, and growth of height and basal diameter of seedlings and saplings were slightly larger in evergreen than in deciduous forest. The spatial distribution patterns by Moristia's index mapping of indivuduals using a lattice method of XY axis within this population showed that seedlings(age up to 2 years) and saplings (age>2 years and height<1m) both evergreen and deciduous forest were more or less aggregated apart from mature trees, and thougth intermediate trees(height>1m and dbh<10cm) had a aggregated distribution pattern, mature trees(dbh>10cm were uniform. In conclusion , the expansion of D. morbfera population from evergreen to deciduous forest accompanied with a mumber of evergreen woody species, and also, emergence and recruitment, and growth of seedlings were greatly influenced moisture and canopy by around community structure.

• 한국농촌건축학회논문집
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• 제20권2호
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• pp.11-18
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• 2018

The purpose of this study is to analyze the structure and use change of the private space according to the balcony expansion and use it as the data of plan design. According to Bay, front length/width ratio and the change of balcony space before and after expansion of space organization of house units were analyzed. Common characteristics of Flat type and Tower type are an increase of the frontage length of house units in an apartment, an increase of the number of front bay, and an increase of integrated LDK focusing on living room. A difference is that Flat type shows high frontage ratio, Bay figure, and spatial arrangement favorable to front openness and lighting. Flat type shows higher area distribution than Tower type in LDK area distribution located in at the plane center. Spatial expandability and visual openness of Flat type are more beneficial than those of Tower type in the planning, and a balcony extension of house units has developed to direction to open more. Tower type creates various block images through a combination of house units focusing on the core. Uses after balcony expansion are area expansion of a balcony-neighboring room, storage space, expansion and function improvement of the variable range, and specialized space different from a neighboring room. In addition, there is no escapable space except for a shelter, so unit plan should be prepared to prevent using it other space of a shelter and to solve moving line of two-way horizontal refuge and vertical refuge.

• 공학논문집
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• 제6권2호
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• pp.141-151
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• 2004

금합금계 매몰재 재료의 물리적 특성은 각각 열팽창계수과 압축강도, 입도 분포에 크게 좌우된다. 일반적으로 금합금계 매몰재는 cristobalite와 quartz, plaster로 주성분을 구성하고 있다. 그리고 cristobalite와 quartz의 열팽창계수는 $2.6\times10^{-6}/^\circC$, $2.32\times10^{-6}/^\circC$, 로 이 두 재료의 혼합비가 매몰재의 열팽창 계수를 변화시키는 매우 중요한 역할을 하고 있다. 현재 국내에서는 금합금계 매몰재는 전량 수입에 의존하고 있고 그 시장 수요 또한 대단히 크다. 따라서 균일한 입도 분포를 가지는 cristobalite와 quartz의 개발과 주조금속의 열팽창과 냉각에 따른 수축력을 고려한 열팽창계수를 가지면서 매몰재의 요구강도에 적합한 압축강도를 가지는 금합금계 매몰재의 개발이 필수적이다. 따라서 본 연구에서는 먼저 균일한 입도를 갖는 cristobalite와 quartz 분체의 제조와 cristobalite와 quartz의 혼합비에 따른 열팽창계수와 압축강도를 비교 분석하였다. 본 연구의 결과로 표면이 매끄럽고 균일한 입도 분포를 갖는 cristobalite와 quartz를 제조하였으며, cristobalite와 quartz의 혼합비가 45:25가 열팽창계수와 압축강도에서 매몰재가 요구하는 조건을 만족하였다.

• 유통과학연구
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• 제13권7호
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• pp.53-61
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• 2015

Purpose - This research analyzes overseas expansion support systems for small- and medium-sized enterprises in Germany and Japan. Germany and Japan have developed overseas expansion support policies for such enterprises. The study then explores the implications for Korea and its local governments. Research design, data, and methodology - We did a comparative analysis of Japan and Germany and their support for overseas expansion of small and medium companies. Data were mainly collected from the Ministry of Economy, Trade and Industry (Japan) and the Germany Trade and Invest (Germany) agency through statistics and literature surveys, and analysis studies. Results - First, human resources cultivation and funding support policies, which both Germany and Japan use as part of small- and medium-sized enterprise policies, should be modified to Korean circumstances and to reflect its own small- and medium-sized enterprise support needs. Second, both the German policies that support overseas expansion of small- and medium-sized enterprises and those of Japan's include the philosophy and methods that put an emphasis on these enterprises, despite the fact that there are big differences in the overseas policies in these two countries. Third, German and Japanese governments are embracing the idea that small- and medium-sized enterprises are key to their national economies and implementing policies based on the ratio occupied by these enterprises in the domestic consumption or GDP. In other words, Germany and Japan consider small- and medium-sized enterprises as central to their nation's industry, and assess them as economic industry that should definitely exist for the continued survival of big businesses, and not just as merely supplemental to big business. Fourth, whereas Germany emphasizes support to product exhibition in its overseas expansion support policies, Japan is providing integrated support containing foreign direct investment to small- and medium-sized enterprises. Fifth, there are differences in the overseas expansion support in Germany and Japan in terms of their support to big business. Whereas Germany considers support to big business unnecessary, Japan is implementing active support policies to areas corresponding to big business. Korea will have to benchmark the policies of Germany and Japan, and decide whether or not to give full support to small- and medium-sized enterprises, while excluding areas supporting big business. Conclusions - Based on this analysis of German and Japanese overseas expansion support policies, we need to choose the policies that will engender a solid outcome and derive modified policies for the circumstances of Korea. Additionally, we can use the comparison of the overseas support policies of Japan and Germany to choose small- and medium-sized enterprise overseas expansion support policies for Korea. However, we cannot provide specific overseas support policies by industry. This point will be referenced as a limitation of this study. In future research, we expect that some researchers will take an empirical approach to exploring Korean overseas expansion support through collecting cases of overseas support policies and interviewing policy authorities.

• 대한전기학회논문지
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• 제40권1호
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• pp.1-9
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• 1991

This paper describes a new method of calculating expected energy generation and loss of load probability (L.O.L.P) for electric power system operation and expansion planning. The method represents an equivalent load duration curve (E.L.D.C) as a mixture of cumulants approximation (M.O.N.A). By regarding a load distribution as many normal distributions-rather than one normal distribution-and representing each of them in terms of Gram-Charlier expansion, we could improve the accuracy of results. We developed an algorithm which automatically determines the number of distribution and demarcation points. In modeling of a supply system, we made subsets of generators according to the number of generator outage: since the calculation of each subset's moment needs to be processed rapidly, we further developed specific recursive formulae. The method is applied to the test systems and the results are compared with those of cumulant, M.O.N.A. and Booth-Baleriaux method. It is verified that the M.O.C.A. method is faster and more accure than any other method.

• 한국해양공학회지
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• 제14권2호
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• pp.19-27
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• 2000

In this paper hydroelastic responses of a very large floating structure(VLFS) are studied theoretically. We have been developed the source and dipole distribution method and pressure distribution method to evaluate the hydrodynamic pressures. The problem of vertical structural responses due to waves are calculated by using finite element method(FEM) and modal expansion method of a free-free beam Hydroelastic responses of VLFS in waves are computed by four methods developed in this paper. As a result the theoretical results of motion responses show good agreements with experimental ones.

• 유통과학연구
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• 제18권5호
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• pp.99-109
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• 2020

Purpose: This study aims to develop and empirically analyze a research model in order to comprehend the relationship among the service quality of market-wholesaler system, re-transaction intention, and recommendation intention of forwarder. Further, we suggest new six factors reflecting the service quality of market-wholesaler system and highlight market expansion of forwarder as a mechanism in the relationship. Research design, data and methodology: The authors developed the new scales measuring the service quality of market-wholesaler system (i.e. trade price, price fluctuation, payment receipt, settlement period, trade information, and customer service) and conducted a cross-sectional survey for 439 forwarders in a wholesale market. And then we performed a series of path analyses to test hypotheses. The hypotheses are as follows. [H1] The service quality of market-wholesaler system will positively affect forwarders' market expansion, [H2] Forwarders' market expansion will positively affect their re-transaction intention, [H3] Forwarders' market expansion will positively affect their recommendation intention, [H4] Forwarders' re-transaction intention will positively affect their recommendation intention. Results: The results showed that all the six factors for the service quality of market-wholesaler system were positively related to market expansion of forwarders. There was a differential effectiveness in the six factors of the service quality. More specifically, the positive effect of customer service factor was the strongest on market expansion of forwarders. And the respective effects of trade price, price fluctuation, settlement period, trade information factors were followed in order. The positive effect of payment receipt factor was the weakest on market expansion of forwarders. Also, market expansion of forwarders was positively related to their re-transaction intention and recommendation intention. Furthermore, market expansion of forwarders was indirectly related to recommendation intention through re-transaction intention as well. Conclusions: The research findings provide important theoretical and practical implications. This study is the first to attempt to test the perception of forwarders for the service quality of market-wholesaler system by developing and using the new scales. Also, there has been a sharp controversy about the effectiveness of market-wholesaler system. The findings support that market-wholesaler system would be activated by empirically verifying the effectiveness of the service quality on the various outcomes.

• 통합자연과학논문집
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• 제16권4호
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• pp.139-145
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• 2023

Due to changes in the distribution system and increased demand for renewable energy, interest in technology to increase the limit capacity of distributed energy grid connection using grid flexible resources is also increasing. Recently, the distribution system system is changing due to the increase in distributed power from renewable energy, and as a result, problems with the limited capacity of the distribution system, such as waiting for renewable energy to connect and increased overload, are occurring. According to the power generation facility status report provided by the Korea Power Exchange, of the total power generation capacity of 134,020 MW as of 2021, power generation capacity through new and renewable energy facilities is 24,855 MW, accounting for approximately 19%, and among them, power generation through solar power accounts for a total portion of the total. It was analyzed that the proportion of solar power generation facilities was high, accounting for 75%. In the future, the proportion of new and renewable energy power generation facilities is expected to increase, and accordingly, an efficient operation plan for the distribution system is needed. Advanced country-type NWAs that can integrate the operation and management of load characteristics for each line of the distribution system, power distribution, regional characteristics, and economic feasibility of distributed power in order to improve distribution network use efficiency without expanding distribution facilities due to the expansion of renewable energy. An integrated operating system is needed. In this study, in order to improve the efficiency of distribution network use without expanding distribution facilities due to the expansion of renewable energy, we developed a method that can integrate the operation and management of load characteristics for each line of the distribution system, power distribution, regional characteristics, and economic feasibility of distributed power. We want to develop an integrated operation system for NWAs similar to that of advanced countries.

• 상하수도학회지
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• 제10권2호
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• pp.55-69
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• 1996

Backwashing is one of the most important processes in water treatment. Several models have been utilized to predict minimum fluidization velocity and expansion of media. However, it is not unusual that the actual bahavior of media dose not agree well with the prediction. This study has investigated the applicability of models in predicting the minimum fluidization velocity of sand media. However even the better model has predicted minimum fluidization velocity 1.1 to 1.8 times higher than actual fluidization velocity. The expansion rate of sand media was inspected. It is found that the actual expansion rate was greater than the predicted. In this study condition, use of $d_{10}$ instead of $d_{60}$ was better to predict the expansion of media. On the contrary to the sand media, the actual expansion of anthracite media was less than that predicted. Sometimes it is reported that the dual media has been overflown during backwashing and mixed severely at the interface. It is because the grain size distribution of anthracite has not been selected properly. The numerical values for media expansion found in this study could be referred as the useful data in operating and/or designing filter media.

• 한국정보처리학회논문지
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• 제7권5호
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• pp.1482-1490
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• 2000

With the increasing availability of information in electronic form, it becomes more important and feasible to have automatic methods to retrieve relevant information in the Internet. A deficiency of traditional information retrieval systems is that search terms are often different from those indexed by the systems. Thus, users ma either retrieve wrong information or miss what they really want. In this paper, e used an automatic query expansion based expansion based on term distribution to enhance the performance of information retrieval. Also this thesis proposed the method for setting the threshold according to area distribution in order choose additional terms.