• Computers and Concrete
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• 제31권2호
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• pp.123-137
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• 2023

To fully understand shear mechanisms and composite effects of circular concrete-filled steel tube (CFST) columns, systematic numerical investigations were conducted in this paper by improved finite element models. The triaxial plastic-damage constitutive model of the concrete and the interactions between the concrete and steel tube were considered. Afterwards, the critical and upper bound shear span ratios of the circular CFST column under lateral shear loading were determined. The composite effects between the two materials were analyzed by comparing the shear resistance with plain concrete column and hollow steel tube. In addition, a method that predicts the shear bearing capacity of a circular CFST column was proposed. The confining effects on the concrete core and the restraining effects on the steel tube were considered in this method. The proposed formula can predict more accurate results than the methods in different codes and references.

• 대기
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• 제15권2호
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• pp.75-90
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• 2005

이 연구에서는 지면-대기 모수화 방안 (BATS1e)이 접합된 미국 국립기상연구센터 (NCAR)에서 개발한 지역기후모델(RegCM2)을 이용하여 지면피복의 변화가 동아시아 여름몬순에 미치는 영향에 대해서 조사하였다. 지면피복 변화의 영향을 분석하기 위하여 두 종류의 지면피복 자료를 이용하였다. 하나는 NCAR에서 제공하는 지면피복 자료 (CTL 실험)이고 다른 하나는 최근의 기상위성자료로부터 직접 분류한 고해상도 지면피복분류 자료(LCV 실험)이다. CTL 실험에서는 중국 중부지역과 몽고지역의 지면온도가 각각 약 $1-3^{\circ}C$ 높고 낮게 모의되었다. 또한 모의 영역 북부지역에서는 강수가 과다하게 모의된 반면 모의영역 남부 바다지역의 강수는 과소하게 모의되었다. 지면피복 변화에 의한 알베도, 거칠기 길이 및 최소기공저항계수와 같은 지면의 생물리적 요소들의 변화는 지면-대기 상호작용을 변경시켰다. 즉, 지면피복이 낙엽활엽수림에서 농지와 관계농지로 변경된 LCV 실험의 중국 중부지역에서는 잠열 속과 풍속이 현저하게 증가되었다. 그 결과 CTL 실험에서 나타났던 중국 중부지역에서의 온난편차가 LCV 실험에서는 대부분 완화되었다. 중국 중부지역에서의 강한 기온 하강은 태평양과 대륙사이의 기압 차를 약화시키고 있다. 남동에서 북서방향으로의 기압경도력이 약화됨에 따라 중국 남부와 남중국해로부터 북동쪽으로의 수증기 수송도 약화되었다. 이러한 수증기 수송의 변화는 모의 영역 북부지역에서의 과다한 강수 모의와 남중국해에서의 과소한 강수모의를 동시에 크게 완화시켰다. 그러나 지면피복의 변화는 특히 7월과 8월에 한반도와 일본 열도 지역에서의 강수를 크게 증기시키고 있다.

• 한국제4기학회지
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• 제17권2호
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• pp.165-165
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• 2003

A borehole core ECSDP-102 (about 68.5 m long) has been investigated to get information on paleoenvironmental changes in response to the sea-level fluctuations during the period of late Quaternary. Several AMS $\^$14/C ages show that the core ECSDP-102 recorded the depositional environments of the northern East China Sea for approximately 60 ka. The Yangtze River discharged huge amounts of sediment into the northern East China Sea during the marine isotope stage (MIS) 3. In particular, $\delta$$\^$13/Corg values reveal that the sedimentary environments of the northern East China Sea, which is similar to the Holocene conditions, have taken place three times during the MIS 3. It is supported by the relatively enriched $\delta$$\^$13/Corg values of -23 to -21$\textperthousand$ during the marine settings of MIS 3 that are characterized by the predominance of marine organic matter akin to the Holocene. Furthermore, we investigated the three Holocene sediment cores, ECSDP-101, ECSDP-101 and YMGR-102, taken from the northern East China Sea off the mouth of the Yangtze River and from the southern Yellow Sea, respectively. Our study was focused primarily on the onset of the post-glacial marine transgression and the reconstructing of paleoenvironmental changes in the East China Sea and the Yellow Sea during the Holocene. AMS $\^$14/C ages indicate that the northern East China Sea and the southern Yellow Sea began to have been flooded at about 13.2 ka BP which is in agreement with the initial marine transgression of the central Yellow Sea (core CC-02). $\delta$$\^$18/O and $\delta$$\^$13/C records of benthic foraminifera Ammonia ketienziensis and $\delta$$\^$13/Corg values provide information on paleoenvironmental changes from brackish (estuarine) to modem marine conditions caused by globally rapid sea-level rise since the last deglaciation. Termination 1 (T1) ended at about 9.0-8.7 ka BP in the southern and central Yellow Sea, whereas T1 lasted until about 6.8 ka BP in the northern East China Sea. This time lag between the two seas indicates that the timing of the post-glacial marine transgression seems to have been primarily influenced by the bathymetry. The present marine regimes in the northern East China Sea and the whole Yellow Sea have been contemporaneously established at about 6.0 ka BP. This is strongly supported by remarkably changes in occurrence of benthic foraminiferal assemblages, $\delta$$\^$18/O and $\delta$$\^$13/C compositions of A. ketienziensis, TOC content and $\delta$$\^$13/Corg values. The $\delta$$\^$18/O values of A. ketienziensis show a distinct shift to heavier values of about 1$\textperthousand$ from the northern East China Sea through the southern to central Yellow Sea. The northward shift of $\^$18/O enrichment may reflect gradually decrease of the bottom water temperature in the northern East China Sea and the Yellow Sea.

• Parasites, Hosts and Diseases
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• 제50권4호
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• pp.379-384
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• 2012

Resistance of Plasmodium spp. to anti-malarial drugs is the primary obstacle in the fight against malaria, and molecular markers for the drug resistance have been applied as an adjunct in the surveillance of the resistance. In this study, we investigated the prevalence of mutations in pvmdr1, pvcrt-o, pvdhfr, and pvdhps genes in temperate-zone P. vivax parasites from central China. A total of 26 isolates were selected, including 8 which were previously shown to have a lower susceptibility to chloroquine in vitro. For pvmdr1, pvcrt-o, and pvdhps genes, no resistance-conferring mutations were discovered. However, a highly prevalent (69.2%), single-point mutation (S117N) was found in pvdhfr gene. In addition, tandem repeat polymorphisms existed in pvdhfr and pvdhps genes, which warranted further studies in relation to the parasite resistance to antifolate drugs. The study further suggests that P. vivax populations in central China may still be relatively susceptible to chloroquine and sulfadoxine-pyrimethamine.

• 무역상무연구
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• 제71권
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• pp.297-324
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• 2016

China not only has the largest amount of rare earth reserves, but it also produces the most rare earth products. However, China lacks appropriate supervision and management systems of its rare earth industry. The Chinese government's inappropriate mechanisms have been cause for reckless development by national rare earth providers characterized by excessive competition, environmental pollution, and smuggling. In response to the problems, China implemented regulatory measures to restructure the rare earth industry. The Chinese central government intensifies its efforts to control the total quantity of rare earth products and tackle environmental pollution. Six leading conglomerates have been selected to promote the Chinese central government's policy. A new environmental guideline has been drawn up to reduce the discharging of wastewater and air pollution substance. Huge transition and a great influence of its policy changes are expected. These policy changes are bound to entail huge transitions, and the policy is expected to have a great influence in the future structure of the rare earth industry. In consideration of these changes, the Korean government, in collaboration with private enterprises needs to take appropriate measures, such as overseas resources development, R&D expansion, tactical stockpiling, professional manpower training and so on.

• 수산해양교육연구
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• 제26권4호
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• pp.749-759
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• 2014

With the rapid development of global economic and trade, the ports in the North-east Asia region have developed rapidly. Ocean shipping plays an irreplaceable role in China's foreign trade. Improvement of China's economy and continuous increase of trade in North-East Asia have made China as the number one in the world in container transport. Tianjin port which is the biggest international trade port in North-east China. Tianjin Binhai New District has incorporated in (CPC Central Committee on the outline of the Eleventh Five-Year Plan for national economic and social development proposals) which had adopted by The Fifth Plenary Session of the 16th CPC Central Committee. However, the competitions between ports are getting intense, the construction of Northeast Asia shipping center is in the ascendant, which bring new opportunity and challenge to the development of Tianjin port logistics. Therefore, Tianjin should according to its characteristics, integrating port resources, exert great efforts in developing port logistics, thus promoting regional economic development. Therefore, it is necessary to make the main study on the development strategy of Tianjin port logistics.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.898-900
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• 2006

China's PM has made great progress both in the research and development of new materials and large scale production, and has played a more and more important role in the world powder metallurgy industry. In this paper, the status quo of advanced PM materials, and traditional PM industries in China, will be discussed.

• Journal of Microbiology and Biotechnology
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• 제33권5호
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• pp.574-581
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• 2023

Nocardiosis is an uncommon opportunistic bacterial infection which becomes a significant health problem due to its increasing incidence and high mortality rate. However, many nocardiosis patients are underdiagnosed by physicians. To summarize the clinical characteristics and management of nocardiosis would help with better diagnosis and prognosis of nocardiosis. This retrospective study was conducted based on the medical records of nocardiosis patients between January 2015 and December 2021 in a tertiary hospital in China. Overall, 44 nocardiosis patients with 54 specimens were included. The patients consisted of 26 males and 18 females with a mean age of 50.4 ± 13.2 years. Among 44 patients, 26 (59.1%) were previously given immunosuppressive therapy. Connective tissue diseases (CTDs) were the most common underlying disease (16/44). The most frequent infection sites were the lungs (17/44) and skin or soft tissues (8/44). Common symptoms included cough (23/44), expectoration (18/44), fever (15/44), and subcutaneous abscesses (15/44). Forty-five out of 54 specimens (83.3%) required over 48 hours of culture time for nocardiosis detection. Thirty-six patients were cured or improved, 5 patients were discharged from the hospital due to poor prognosis, and 1 patient died. The average diagnosis time of poor prognosis cases was 19.7 days, which was significantly longer than those of improved or cured patients (7.3 days). Immunosuppressed patients comprise a large part of nocardiosis cases, which is worth attention in clinical practice. Early diagnosis, specifically through prolonged cultivation time of specimen, could help achieve better prognosis of nocardiosis patients.

• 한국항만경제학회지
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• 제17권2호
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• pp.111-137
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• 2001

The establishment of the WTO system means that the global age of trade has officially arrived. Since the integration of the world economy brings about the free movement of goods and services between nations, it is inevitable that sea-bound freight will continue to increase. A recent World Bank report says that China and Korea will be the first and seventh largest economic Powers, respectively, by the year 2020. In particular, the Korea peninsula has a geo-political advantage in being developed as a major Northeast Asian container center. Moreover China's swift uprising needs new order of trade for economy belt in Northeast Asia. Therefore, it can be said that Kunsan Port. which has already been designated as a free trade zone, has greater potential to rise as a regional beach-head port and main region for foreign investment. As such. Kunsan Port will play a major role in accelerating the emergence of the West Sea in international trade. There are several strategies for developing Kunsan Port into a central container port: 1) develop Kunsan port Into an import/export front base f3r multinational corporations, 2) develop Kunsan container port into the core composite container-linked central port, 3) attract foreign investment to the Kunsan Free Trade Area so as to promote balanced development among the regions of Korea, 4) support the central government and local governments to accelerate the coming of the "West Sea Era." These recommendations call for urgent implementation.

• The Journal of Asian Finance, Economics and Business
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• 제8권5호
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• pp.473-483
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• 2021

This study's fundamental purpose is to examine the personality factors of business school faculty members in job satisfaction and job performance. Results show the significant impact of multicultural faculty members' job performance in a diverse environment in the Business schools of Karachi. The data is collected through the multi questionnaires from the various teaching, non-teaching staff, and students of private business schools of Karachi in Pakistan. The data has been tested through the Jamovi-by-medmod, and the regression model is to scrutinize and find the effect dependent variables to mediation. Simultaneously, results are calculated by mediation estimates and path estimates through the medmod technic and regression test from data. It provides a comprehensive insight into various factors such as personality traits, self-efficiency, Psychological diversity climate, self-esteem, and human resource management practices. These are the primary evaluated factors that affect multicultural faculty members' job satisfaction and job performance. However, results show a positive relationship between diversity climate and job performance, which mediates by job satisfaction. Similarly, personality traits show a positive relationship with job performance that mediates by job satisfaction. Correspondingly, self-esteem spectacles are a positive inter-relationship with job performance which is mediated by job satisfaction.