• Title/Summary/Keyword: growth dynamics

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Research on Eco-efficiently Evaluation of China Based on DEA-Malmquist Index (DEA-Malmquist 지수를 이용한 중국 환경효율에 관한 평가 연구)

  • YULIN, LU;YAN, HE
    • Journal of Digital Convergence
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    • v.20 no.5
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    • pp.375-381
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    • 2022
  • The DEA-BCC model. And the Malmquist index have been used, from static and dynamic perspectives, to measure the eco-efficiency of 30 cities and provinces in China from 2011 to 2020. The results shows that: the average static eco-efficiency of 30 cities and provinces in China is 0.643. Differences exists all over China. While Shanghai and Beijing are ecologically efficient, other 28 cities and provinces are faced with different extents of inefficiency. There are also differences among regions, which generally show the spatial distribution pattern with high efficiency in the eastern regions while low in the western regions. The Malmquist index of eco-efficiency in total 30 cities and provinces shows a healthy growth trend, and the technological progress. Acts as its main driving force. Therefore, eastern regions should enhance the. radiation capacity, strengthen the synergy among regions, give full play to. The advantages of each regions. It is sensible to improve the eco-efficiency by means of optimizing the industrial structure, enhancing the technological level and improving eco-efficiency of China and realizing green development.

Design of Optimal Thermal Structure for DUT Shell using Fluid Analysis (유동해석을 활용한 DUT Shell의 최적 방열구조 설계)

  • Jeong-Gu Lee;Byung-jin Jin;Yong-Hyeon Kim;Young-Chul Bae
    • The Journal of the Korea institute of electronic communication sciences
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    • v.18 no.4
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    • pp.641-648
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    • 2023
  • Recently, the rapid growth of artificial intelligence among the 4th industrial revolution has progressed based on the performance improvement of semiconductor, and circuit integration. According to transistors, which help operation of internal electronic devices and equipment that have been progressed to be more complicated and miniaturized, the control of heat generation and improvement of heat dissipation efficiency have emerged as new performance indicators. The DUT(Device Under Test) Shell is equipment which detects malfunction transistor by evaluating the durability of transistor through heat dissipation in a state where the power is cut off at an arbitrary heating point applying the rating current to inspect the transistor. Since the DUT shell can test more transistor at the same time according to the heat dissipation structure inside the equipment, the heat dissipation efficiency has a direct relationship with the malfunction transistor detection efficiency. Thus, in this paper, we propose various method for PCB configuration structure to optimize heat dissipation of DUT shell and we also propose various transformation and thermal analysis of optimal DUT shell using computational fluid dynamics.

Corruption Risks in the System of Providing Economic Security of the State

  • Pinchuk, Vitaliy;Shaposhnykova, Iryna;Kuvakin, Serhiy;Kozak, Kateryna;Popova, Liubov;Lopashchuk, Inna
    • International Journal of Computer Science & Network Security
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    • v.22 no.1
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    • pp.69-76
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    • 2022
  • At the current stage of globalization and European integration of Ukraine, the aspects related to the effective fight against corruption in the system of economic security of our country are receiving more and more attention, as they become a prerequisite for continuing reforms based on international funding. In order to consider this issue and solve this problem, the necessary step is to develop and implement real mechanisms of the system for detecting and preventing corrupt behavior, which are based on international anti-corruption standards. The leading component of this system is the management of corruption risks in the system of economic security in order to identify them and implement measures to reduce them. This study analyzes the corruption perception index in Ukraine in recent years, which showed a positive, albeit somewhat slow dynamics of its growth, indicating a gradual increase in overcoming corruption through the introduction of a number of anti-corruption measures and changes. It is proved that the current stage of socio-economic development of the country contributes to strengthening the processes of combating corruption and preventing corruption risks, creating an effective and efficient anti-corruption system of the state. The concept of "corruption" was studied, it was found that in the field of public administration it is considered from different positions and is closely related to the concept of "corruption risks". The essence and features of corruption risks are studied, the preconditions of their occurrence are formulated, the relationship between the causes of corruption risks and economic security in the field of public authority has been established. The system of corruption risk management is considered and its components are characterized. It is proposed to increase the effectiveness of anticorruption policy through the implementation of measures aimed at investigating the causes of corruption risks, as well as developed effective and effective means of reducing corruption risks within the system of economic security

중국인 학습자를 위한 문화교육으로서 한·중 소설 비교읽기 -4.19와 문화대혁명을 중심으로-

  • Jeon, Yeong-Ui;Eom, Yeong-Uk
    • 중국학논총
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    • no.62
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    • pp.85-100
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    • 2019
  • The article purpose is 'Reading Chinese translation text as a Korean integrated education for Chinese students'. Although number of foreign students has increased rapidly to the economic growth of Korea, the influence of Korean Wave, and the popularity of Korean popular culture like K-pop at domestic universities but the problems of their curriculum have been found in many places. Korean literary education through novel text has an important place in Korean studies, but literary education is often excluded in Korean language education as a foreign language education. Chinese students already have background knowledge of Korean translation novels through Chinese novels. They can get the learning effect as the Korean language study. Second, they can compared with Korean national violence and Chinese national violence through 'Red Revolution' and understand about Korean-Chinese understanding of the times, social and cultural phenomena, Third, they are able to study the theory of literature itself. also It was the educational purpose pursued by the humanities. Chinese students develop their Korean language skills by studying the Brothers which are translated into Korean, and we can see the similarities and differences of national violence by comparing Korea's '4.19' with China's 'Cultural Revolution' After comparing people, background, dynamics of the space where they are located, we can raise awareness of the historical and social problems of both countries. It is possible to study subjects' memories of space, change of local meaning, the formation of urban space or individual space in the text in the specific space where national violence occurs. In this way, the method of learning Korean integrated education through Brothers of the Chinese translation novels makes an opportunity to look at national violence in the Korean-Chinese space of the 1960s and 1970s. It has a subjective perspective from subordination to the nationality of the modern nation-state. This is an educational effect that can be obtained through reading a Chinese translation novel as a Korean language integrated education.

Weather Conditions Drive the Damage Area Caused by Armillaria Root Disease in Coniferous Forests across Poland

  • Pawel Lech;Oksana Mychayliv;Robert Hildebrand;Olga Orman
    • The Plant Pathology Journal
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    • v.39 no.6
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    • pp.548-565
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    • 2023
  • Armillaria root disease affects forests around the world. It occurs in many habitats and causes losses in the infested stands. Weather conditions are important factors for growth and development of Armillaria species. Yet, the relation between occurrence of damage caused by Armillaria disease and weather variables are still poorly understood. Thus, we used generalized linear mixed models to determine the relationship between weather conditions of current and previous year (temperature, precipitation and their deviation from long-term averages, air humidity and soil temperature) and the incidence of Armillaria-induced damage in young (up to 20 years old) and older (over 20 years old) coniferous stands in selected forest districts across Poland. We used unique data, gathered over the course of 23 years (1987-2009) on tree damage incidence from Armillaria root disease and meteorological parameters from the 24-year period (1986-2009) to reflect the dynamics of damage occurrence and weather conditions. Weather parameters were better predictors of damage caused by Armillaria disease in younger stands than in older ones. The strongest predictor was soil temperature, especially that of the previous year growing season and the current year spring. We found that temperature and precipitation of different seasons in previous year had more pronounced effect on the young stand area affected by Armillaria. Each stand's age class was characterized by a different set of meteorological parameters that explained the area of disease occurrence. Moreover, forest district was included in all models and thus, was an important variable in explaining the stand area affected by Armillaria.

Three-dimensional CFD simulation of geyser boiling in high-temperature sodium heat pipe

  • Dahai Wang;Yugao Ma;Fangjun Hong
    • Nuclear Engineering and Technology
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    • v.56 no.6
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    • pp.2029-2038
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    • 2024
  • A deep understanding of the characteristics and mechanism of geyser boiling and capillary pumping is necessary to optimize a high-temperature sodium heat pipe. In this work, the Volume of Fluid (VOF) two-phase model and the capillary force model in the mesh wick were used to model the complex phase change and fluid flow in the heat pipe. Computational Fluid Dynamics (CFD) simulations successfully predicted the process of bubble nucleation, growth, aggregation, and detachment from the wall in the liquid pool of the evaporation section of the heat pipe in horizontal and tilted states, as well as the reflux phenomenon of capillary suction within the wick. The accuracy and stability of the capillary force model within the wick were verified. In addition, the causes of geyser boiling in heat pipes were analyzed by extracting the oscillation distribution of heat pipe wall temperature. The results show that adding the capillary force model within the wick structure can reasonably simulate the liquid backflow phenomenon at the condensation; Under the horizontal and inclined operating conditions of the heat pipe, the phenomenon of local dry-out will occur, resulting in a sharp increase in local temperature. The speed of bubble detachment and the timely reflux of liquid sodium (condensate) replenishment in the wick play a vital role in the geyser temperature oscillation of the tube wall. The numerical simulation method and the results of this study are anticipated to provide a good reference for the investigation of geyser boiling in high-temperature heat pipes.

Two-Phase Anaerobic Digestion of Food and Livestock Wastewater and Hygienic Aspects of the Digested Water (음식물폐기물과 축산분뇨 혼합폐수의 이상혐기소화에 따른 소화액의 위생성 연구)

  • Jeong, Doo-Young;Chung, Myung-Hee;Kim, Young-Jun
    • Journal of the Korea Organic Resources Recycling Association
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    • v.17 no.4
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    • pp.66-73
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    • 2009
  • Temperature phase anaerobic co-digestion process was conducted with the one to one mixture of food wastewater with livestock wastewater, and the presence and the dynamics of various pathogenic microorganisms was analyzed. The mixture contained various enteric and pathogenic bacteria, such as Escherichia coli. Enterobacteriaceae, Coliform bacteria. Staphylococcus aureus, Salmonella, Shigella, Listeria, and Yeast. Anaerobic digestion has become stabilized around 21 days after the reaction started, showing about 80% to 90% of remarkable reduction rates of microorganisms until this period in acidogenic reactor (AR) and methanogenic reactor (MR), respect ively. After stabilization, the average reduction rate of organic matter was recorded as around 60% in MR. Most microorganisms in the effluent were not detected at around the last period of the reaction, except Listeria and S. aureus, which showed the growth even at the last day of the reaction.

Variation Analysis of Phytoplankton Communities in Northern Gamak Bay, Korea (북부 가막만의 식물플랑크톤 군집 변동 해석)

  • Oh, Seok-Jin;Park, Jong-Sik;Yoon, Yang-Ho;Yang, Han-Soeb
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.15 no.4
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    • pp.329-338
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    • 2009
  • Using physiological data which had been already published, we investigated variation of phytoplankton communities due to changes of marine environmental factor at 2 stations of northern Gamak Bay from November 2007 to September 2008. Dominant species (occupied species above 10%) were dinoflagellates 1 species and diatom 11 species. Diatom Skeletonema costatum was observed as dominant species during the periods except in summer (i.e. July and August), especially, which occupied above 90% in December. On the other hand, dominant species during summer were diatom Eucampia zodiacus and Chaetoceros spp., Considering the results of other physiological studies, S. costatum might be non-dominant species during summer by following reasons 1) growth rate of E. zodiacus might be taster than that of S. costatum under the temperature during summer although both S. costatum and E. zodiacus are eurythermal and euryhaline species. 2) Species as E. zodiacus characterized by low affinity with light might have a chance to be dominant with increasing optical transparency due to low suspended solids in July. 3) In aspect of nutrition, species of growth strategist as S. costatum could be dominant in relatively low concentration of phosphate and species of storage strategist as E. zodiacus could be dominant in relatively high concentration of phosphate during summer in this study area. In order to understand the phytoplankton dynamics in detail, the physiological informations about strains isolated from this study area are necessary because physiological conditions are different depending on isolated area.

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Locational Dynamics and Spatial Impacts of Producer Services in Korea (생산자서비스의 입지적 특성과 공간적 영향에 관한 연구)

  • Yong Gyun Lee
    • Journal of the Korean Geographical Society
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    • v.38 no.3
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    • pp.444-462
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    • 2003
  • There has been emerging general agreement on the relative importance of producer services in a economy. This research describes the spatial patterns and trends in producer services at different spatial scales. The other research aim is to explain the impacts of producer services on spatial changes at the national level and at the intra-metropolitan level in Seoul. Producer services have highly concentrated in metropolises, especially Seoul. Between 1986 to 2001, an important spatial change in the producer services at the national level has been their growth in the Capital Region, reinforcing the role and function of Seoul. This reinforced role of Seoul is closely related to its competitive advantages arising from economies of urban. There have been some dramatic changes in the location of producer services within Seoul. The most important change was the growth of the Youngdong area, previously a sub-center for businesses, as the most important location for producer services, exceeding the previous dominant role of the CBD area. The changing urban form of Seoul is partly related to the onset of some diseconomies of urbanization in the CBD, while at the same time Youngdong has reached a stage at which it is benefiting from the agglomeration of a variety of firms, in addition to a favourable social and physical infrastructure.

Ecological diagnosis of the Gongjicheon water system using length-weight relationship and condition factor(K) of population of the Zacco platypus (피라미 개체군의 length-weight relationship 및 condition factor(K)를 이용한 공지천수계의 생태적 진단)

  • Lee, Kwang-Yeol;Jang, Hara;Yun, Youngjin;Park, Seungchul;Kim, Joon Chul;Lee, Jaeyong;Choi, Jaeseok
    • Journal of Environmental Impact Assessment
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    • v.23 no.2
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    • pp.137-149
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    • 2014
  • The purpose of this study is to investigate the dynamics of the Zacco platypus population among streams in the Gongjicheon water system, Korea from December 2010 to October 2011. In this study, fish fauna was collected 27 Species belonged to 9 Families. The legal protection species, such as a natural monument and endangered species was not collected. Korean endemic species was collected 6 species including to Z. koreanus. The ratio of Korean endemic species was 22.6%, and it was lower than 51.3% that average of Korean endemic species in the Hangang water system. About these status, we considered that Gongjicheon water system had lost of the unique characteristics of the Hangang water system by the anthropogenic disturbances. The result of analysis to length-weight relationship and condition factor(K) of Z. platypus population in the Gongjicheon water system, the regression coefficient value(b) to indication of growth degree of the population was 3.04 and the slope of the condition factor(K) to indication of corpulency had positive value, respectively. These results seems to be that the Z. platypus population is maintained to a little unstably. In addition, the values of the degree of growth and corpulence were very low than the other natural streams in the Hangang water system, so it considered that the many artificially stress factors are occurred in this study area. These results are similar to Fish Assessment Index(FAI) in the assessment for health of aquatic ecosystem. Therefore, we are considered to require precise investigation and sustained monitoring for the restorations of stream ecosystem in the Gongjicheon water system.