• Steel and Composite Structures
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• v.19 no.1
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• pp.21-41
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• 2015

Push-out tests have been conducted on 18 rectangular concrete-filled steel tubular (CFST) columns with the aim of studying the bond behaviour between the steel tube and the concrete infill. The obtained load-slip response and the distribution of the interface bond stress along the member length and around the cross-section for various load levels, as derived from measured axial strain gradients in the steel tube, are reported. Concrete compressive strength, interface length, cross-sectional dimensions and different interface conditions were varied to assess their effect on the ultimate bond stress. The test results indicate that lubricating the steel-concrete interface always had a significant adverse effect on the interface bond strength. Among the other variables considered, concrete compressive strength and cross-section size were found to have a pronounced effect on the bond strength of non-lubricated specimens for the range of cross-section geometries considered, which is not reflected in the European structural design code for composite structures, EN 1994-1-1 (2004). Finally, based on nonlinear regression of the test data generated in the present study, supplemented by additional data obtained from the literature, an empirical equation has been proposed for predicting the average ultimate bond strength for SHS and RHS filled with normal strength concrete.

• Korean Journal of Remote Sensing
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• v.38 no.6_2
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• pp.1677-1689
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• 2022

Air pollution is social issue that has long-term and short-term harmful effect on the health of animals, plants, and environments. Chimneys are the primary source of air pollutants that pollute the atmosphere, so their location and type must be detected and monitored. Power plants and industrial complexes where chimneys emit air pollutants, are much less accessible and have a large site, making direct monitoring cost-inefficient and time-inefficient. As a result, research on detecting chimneys using remote sensing data has recently been conducted. In this study, YOLOv5-based chimney detection model was generated using BUAA-FFPP60 open dataset create for power plants in Hebei Province, Tianjin, and Beijing, China. To improve the detection model's performance, data split and data augmentation techniques were used, and a training strategy was developed for optimal model generation. The model's performance was confirmed using various indicators such as precision and recall, and the model's performance was finally evaluated by comparing it to existing studies using the same dataset.

• Journal of Korean Library and Information Science Society
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• v.53 no.2
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• pp.241-264
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• 2022

The Studies related to the Gwangju Student Movement which occurred in 1929 have been diversified on research topics since 2018. A number of studies have been conducted on the process of spreading the Gwangju Student Movement abroad. However, those studies show limitations in terms of difficulty in discovering new historical materials and the absence of research methods. Therefore, the researchers have analyzed the process of spreading Gwangju Student Movement abroad as the process of spreading information based on library and information science. The researchers have newly discovered Chinese newspaper records at that times and conducted 2-mode network analysis. The results are as follows: first, 125 Chinese newspaper records were discovered from 16 kinds of newspapers and 104 articles of them were newly discovered; second, the researcher found that there were earlier articles than the first claimed by previous researchers in their studies; third, Newspapers in Beijing, Sacheon, Shanghai, Tianjin, and Honam regions in China mainly reported the first and second joint demonstrations in Seoul and Gwangju. The significance of this study is to expand and diversify the research on the Gwangju Student Movement through network analysis.

• Environmental and Resource Economics Review
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• v.26 no.2
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• pp.205-227
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• 2017

Today, the global environment has so many serious problems such as global warming, ecological destruction and air pollution. Now China is the second largest carbon emissions country in the world. In this paper, we estimated the ratio of GDP per unit of carbon emissions for each of 30 provinces in China, and then also estimated the carbon emission efficiency of 30 provinces and analyzed the factors that affecting them. There are differences in carbon emission efficiency among different provinces, and carbon emission efficiency is relatively high in Hainan Province, Beijing, and Tianjin. In the regression results of the factors affecting the carbon emission efficiency, when the proportion of service industries is higher, the efficiency is higher. Also, when the higher the proportion of heavy industry and the higher the proportion of coal consumption are estimated to be worse.

• Steel and Composite Structures
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• v.13 no.6
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• pp.501-519
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• 2012

As an alternative to current conventional force-based assessment methods, the energy-based seismic performance of a code-designed 20-storey high-rise steel building is evaluated in this paper. Using 3D nonlinear dynamic time-history method with consideration of additional material damping effect, the influences of different restoring force models and P-${\Delta}/{\delta}$ effects on energy components are investigated. By combining equivalent viscous damping and hysteretic damping ratios of the structure subjected to strong ground motions, a new damping model, which is amplitude-dependent, is discussed in detail. According to the analytical results, all energy components are affected to various extents by P-${\Delta}/{\delta}$ effects and a difference of less than 10% is observed; the energy values of the structure without consideration of P-${\Delta}/{\delta}$ effects are larger, while the restoring force models have a minor effect on seismic input energy with a difference of less than 5%, but they have a certain effect on both viscous damping energy and hysteretic energy with a difference of about 5~15%. The paper shows that the use of the hysteretic energy at its ultimate state as a seismic design parameter has more advantages than seismic input energy since it presents a more stable value. The total damping ratio of a structure consists of viscous damping ratio and hysteretic damping ratio and it is found that the equivalent viscous damping ratio is a constant for the structure, while the equivalent hysteretic damping ratio approximately increases linearly with structural response in elasto-plastic stage.

• Journal of Fashion Business
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• v.6 no.4
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• pp.113-124
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• 2002

The purpose on this study identified the purchasing conditions of Sports wear of the Chinese men residing in Beijing, Shanghai, Dalian, Tianjin, Harbin and Guangzhou, so that it helped sports wear manufacturers and retailers offer the basic data. For the study, a questionnaire used as a method of measurement, the 863 Chinese men were selected as a sample, SAS(Statistical Analysis System) program was used to analyze the data. The results from the study were as follows: 1. According to the investigation, the most preferred sports of Chinese men is soccer, as a whole. Swimming, basketball and ping-pong keep rank the next to soccer. 2. Accordingly age, area, profession and income, Chinese men maintained sports suit in order of training suit, swimming suit, soccer suit, tennis suit. It is found that holding amount of high-quality sports wears as ski, golf is on a low level. 3. It is appeared that Chinese men purchased in good order as follow brand: No-bran, Nike, Lening, Adidas. And except Nike, they purchased more Lening brand than foreign sports brand. 4. As the result of researching on the item of sports wear, it is found that they purchased various kind items in a higher rank 5 brands. 5. Sports wear's color that Chinese men purchased is blue, white, black, red. 6. The purchasing price that Chinese men favored is 200$\sim$599RMB. Thus, they expend average per head for sports suit buying, 486.0RMB. 7. Chinese men purchased very often at specialty store. And, coefficient of utilization at the usual market is on a low level. 8. In purchasing satisfaction, 80 % Chinese men were satisfied with goods(sports wear) that purchased in a higher rank 5 brands. So, average satisfaction degree showed over 3.8 as a high rate. 9. According to the result of satisfaction on Chinese men, 70% Chinese men showed satisfaction. Therefore, the average of satisfaction degree appeared 3.81 as a high rate.

• Journal of Ginseng Research
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• v.48 no.5
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• pp.504-510
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• 2024

Background: As a physiological function of body, immunity can maintain health by identifying itself and excluding others. With economic development and increasingly fierce social competition, the number of sub-healthy population is gradually increasing, and the most basic problem exposed is human hypoimmunity. Hypoimmunity can be manifested as often feeling tired, catching colds, mental depression, etc. In order to enhance immunity, eating healthy foods with the effect of enhancing immunity may become an effective choice. KRG has pharmacological effects of enhancing immunity. Because the screening and evaluation method of immune population are not unified, there are relatively few KRG immunity tests for sub-health population. It is of great significance to study the effect of KRG on people with hypoimmunity to improve sub-health status. Methods: This was a 180-day, randomized, double-blind, placebo-controlled clinical trial. According to the trial scheme design, 119 qualified subjects were included and randomly divided into the test group taking KRG and the placebo control group. Subjects need to check safety indicators (blood pressure and heart rate, blood routine, liver and kidney function, urine routine and stool routine) and efficacy indicators (main and secondary) inspection at baseline, efficacy indicators inspection during the mid-term of the test (90th days of administration), safety and efficacy indicators inspection after the test (180th days of administration). Results: After the test, the safety indicators of placebo control group and KRG test group were basically within the normal range, and there is no significant difference in fireness score between the two groups. Through follow-up interviews, it was found that the subjects in the test group and the control group had no adverse reactions and allergic reactions such as nausea, flatulence, diarrhea, and abdominal pain during the test period. Self-comparison of the test group, the results of the main efficacy indicators: (1) immune related health scores were significantly improved in the mid-term and after the test (P < 0.01), (2) CD3 and CD4/CD8 increased significantly after the test (P < 0.05), (3) IgG, IgA, IgM and WBC increased significantly in the mid-term and after the test (P < 0.01); the results of the secondary efficacy indicators: (1) TNF-α decreased significantly in the midterm (P < 0.05), IFN-γ decreased significantly in the mid-term (P < 0.01), (2) NK increased significantly in the mid-term and after the test (P < 0.05), (3) monocyte increased significantly in the mid-term and after the test (P < 0.01). Inter-group comparison of the test group and the control group, the results of the main efficacy indicators: (1) immune related health scores were higher than that of the control group in the mid-term and after the test (P < 0.01), (2) IgA of the test group was higher than that of the control group in the mid-term and after the test (P < 0.05); the results of the secondary efficacy indicators: (1) WBC of the test group was higher than that of the control group in the mid-term (P < 0.05); (2) monocytes of the test group were higher than that of the control group in the mid-term and after the test (P < 0.05), neutrophils of the test group were higher than that of the control group in the mid-term (P < 0.05). Conclusion: Taking KRG has no adverse effects on the health of the subjects. According to the standard of clinical trial scheme, the immune related health scores and IgA in the main efficacy indicators were positive, which shows that KRG is helpful in enhancing human immunity.

• Journal of the Korean Regional Science Association
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• v.15 no.2
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• pp.131-153
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• 1999

Since 1980's there have been two trends that obviously developed in the would -- economics globalization and urban internationalization. China, with is reform and opening-up policy and rapid economic growth, keeps pace with these two trends. The term "International City" has no putative standard or definition. If we make an analogue of urban functional hierarchy in the world with a pyramid, the International Citiesa are the few elites on its top. The highest level international cities can be called "World City" or "Global City". In today's new international division of labor, they are diversified leading cities with control capacity on a world scale, like New York, London, and Tokyo. The secondary international cities are either diversified cities with influence and regulative functions on multinational scale or specialized cities on politics, economics, culture, or other aspects with worldwide impact. Judged by different criteria, there is no city that is qualified as International City with the exception of Hong Kong, which was returned to the P.R. of China in 1997. Nevertheless, Some favorable conditions for the development of the international city still exist in China. This country is already the sixth largest economic entity in the world, and the second largest economic entity in the world, and the second largest one if GNP estimated by ppp. Furthermore its import and export value make up for 40% of its GNP, indicating that China is repidly merging into global economy. In this 1, 2 billion-population country, the difference of economic levels between urban and rural, coastal and inland regions is so big that a few metropolises in the coastal region have the possibilities and potentials to develop into international cities regardless of rather low GNP per capita of the whole country. This article will focus on analysis from several perspectives, such as the proportion of foreign trade values in GDP, the proportion of imports and exports by foreign funded enterprises in total foreign trade value; distribution of the 500 largest foreign-funded enterprises; distribution of the 500 enterprises with largest import and export values; distrigbution of foreign computer and telecom companies with offices in China; the number of outward flights per week and the international tourists; the value of foreign capital used in cities and so on. From this analysis, it is predicted that Chinese international cities will surely emergy from the eastern coastal regions and they must be the core cities of metropolitan interlocking regions that have been formed or in the process of forming. Those international cities will arise from south to north in turn : Hong Kong-Guangzhu, Shanghai, Beijing-Tianjin, and perhaps the last one is Dalian-Shenyang. The other side of this issue is that there is a long way for the coming international cities in China except Hong Kong. At least China and these core cities must continually devote to (1) improve the regional composition of foreign capital sources. (2) improve the composition of export commodities. (3) improve the investment environment (including hard and soft environment) to attract more transnational corporations to settle. (4) deepen the reform of state-owned enterprises and establish Chinese own transnational corporations to enter the world market.ons to enter the world market.

• Journal of the Korean association of regional geographers
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• v.14 no.5
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• pp.492-506
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• 2008

This paper aims to explore the characteristics of regional network of Korean firms in Dalian City, China, which is focused on social, cultural and institutional characteristics. To achieve this goal, the paper attempts to analyze the supply of raw material and parts, sales and cooperative relations of the firms. Among Korean firms in Dalian City, the characteristic of non-local network can be seen in supply enterprise of raw material, parts and semi products. On the other hand, a tighter local network relationship can be seen in sales. Large companies appear stronger in non-local network than small businesses and small businesses are stronger in local network. In terms of cooperation among enterprises, many firms have networks of joint marketing, joint use of equipments, exchange of techniques and information with the supply enterprise. With the customer enterprise, there is a network in joint marketing and manpower training. Especially, most of the customer enterprises are Chinese ones, which have extensive networks in big cities, such as in Beijing, Shanghai, Guangzhou, Tianjin and Dalian. In local network, the Korean firms in Dalian cooperate in product development, finance and manpower training with local firms. And in non-local cooperation, Korean firms are active in tech support, information exchange and R&D.

• Korean journal of applied entomology
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• v.53 no.2
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• pp.135-139
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• 2014

Anastatus orientalis Yang et Gibson(Hymenoptera : Eupelmidae) is the egg parasitoid of lantern-fly Lycorma delicatula. The natural parasitism showed that: (1)the highest parasitism rate of egg masses was 68.96% in Yantai Shandong; (2)the highest parasitism rate of eggs was 32.98% in Haidian Beijing; (3)the eggs of parasitoids hatched and emerged earliest in Yangling Shaanxi; emergence time of different populations in Yantai, Guangang Tianjin, Qinhuangdao Hebei and Haidian was similar; (4) the sex ratios were various among the populations ranging from 1.92 to 1.94; (5) parasitism rates of egg masses on Populus sp., Salix sp. and Toona sinensis were not significantly different, the highest parasitism rate of egg masses was 64.3% on T. sinensis, and the lowest rate was 27.4% on Ailanthus altissima; (6)parasitism rates of eggs on Populus sp., Salix sp., T. sinensis and A. altissima were not significantly different, about 30% averagely.