• Title/Summary/Keyword: Key factors

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Insights into the Gut Microbiota of Freshwater Shrimp and Its Associations with the Surrounding Microbiota and Environmental Factors

  • Zhao, Yanting;Duan, Cuilan;Zhang, Xu-xiang;Chen, Huangen;Ren, Hongqiang;Yin, Ying;Ye, Lin
    • Journal of Microbiology and Biotechnology
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    • v.28 no.6
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    • pp.946-956
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    • 2018
  • The gut microbiota of aquatic animals plays a crucial role in host health through nutrient acquisition and outcompetition of pathogens. In this study, on the basis of the high-throughput sequencing of 16S rRNA gene amplicons, we examined the bacterial communities in the gut of freshwater shrimp (Macrobrachium nipponense) and in their living environments (sediment and pond water) and analyzed the effects of abiotic and biotic factors on the shrimp gut bacterial communities. High bacterial heterogeneity was observed in the freshwater shrimp gut samples, and the result indicated that both the surrounding bacterial community and water quality factors (particularly dissolved oxygen and temperature) could affect the shrimp gut bacterial community. Despite the observed heterogeneity, 57 genera, constituting 38-99% of the total genera in each of the 40 shrimp gut samples, were identified as the main bacterial population in the gut of M. nipponense. In addition, a high diversity and abundance of lactic acid bacteria (26 genera), which could play significant roles in the digestion process in shrimp, were observed in the shrimp gut samples. Overall, this study provides insights into the gut bacterial communities of freshwater shrimp and basic information for shrimp farming regarding the application of probiotics and disease prevention.

Short-Term Photovoltaic Power Generation Forecasting Based on Environmental Factors and GA-SVM

  • Wang, Jidong;Ran, Ran;Song, Zhilin;Sun, Jiawen
    • Journal of Electrical Engineering and Technology
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    • v.12 no.1
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    • pp.64-71
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    • 2017
  • Considering the volatility, intermittent and random of photovoltaic (PV) generation systems, accurate forecasting of PV power output is important for the grid scheduling and energy management. In order to improve the accuracy of short-term power forecasting of PV systems, this paper proposes a prediction model based on environmental factors and support vector machine optimized by genetic algorithm (GA-SVM). In order to improve the prediction accuracy of this model, weather conditions are divided into three types, and the gray correlation coefficient algorithm is used to find out a similar day of the predicted day. To avoid parameters optimization into local optima, this paper uses genetic algorithm to optimize SVM parameters. Example verification shows that the prediction accuracy in three types of weather will remain at between 10% -15% and the short-term PV power forecasting model proposed is effective and promising.

Variability analysis on modal parameters of Runyang Bridge during Typhoon Masta

  • Mao, Jian-Xiao;Wang, Hao;Xun, Zhi-Xiang;Zou, Zhong-Qin
    • Smart Structures and Systems
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    • v.19 no.6
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    • pp.653-663
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    • 2017
  • The modal parameters of the deck of Runyang Suspension Bridge (RSB) as well as their relationships with wind and temperature are studied based on the data recorded by its Structural Health Monitoring System (SHMS). Firstly, frequency analysis on the vertical responses at the two sides of the deck is carried out to distinguish the vertical and torsional vibration modes. Then, the vertical, torsional and lateral modal parameters of the deck of RSB are identified using Hilbert-Huang Transform (HHT) and validated by the identified results before RSB was opened to traffic. On the basis of this, the modal frequencies and damping ratios of RSB during the whole process of Typhoon Masta are obtained. And the correlation analysis on the modal parameters and wind environmental factors is then conducted. Results show that the HHT can achieve an accurate modal identification of RSB and the damping ratios show an obvious decay trend as the frequencies increase. Besides, compared to frequencies, the damping ratios are more sensitive to the environmental factors, in particular, the wind speed. Further study on configuring the variation law of modal parameters related with environmental factors should be continued.

An Analysis on Work Delay Factors in Apartment House Construction (공동주택 공사의 작업지연요소 분석)

  • Ahn, Sang-Hyun;Yu, Jung-Ho;Kim, Chang-Duk
    • Korean Journal of Construction Engineering and Management
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    • v.8 no.6
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    • pp.159-166
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    • 2007
  • Work delay is one of the facts that make the reliability of construction projects decrease. Therefore, it is important to classify and prioritize the delay factors. This research analyzed key delay factors in apartment house construction through survey. The results of analysis are as follows. (1) Insufficient work force is the key delay factor in structural and finish work. (2) Improper craft of worker is the key delay factor in electrical work. (3) Incompletion of proceeding work is the key delay factor in mechanical work.

Evaluation of Key Success Factors for Web Design in Taiwan's Bike Case Study

  • LAI, I-Sung;HUANG, Yung-Fu;SIANG, Jie-Hua;WENG, Ming-Wei
    • The Journal of Asian Finance, Economics and Business
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    • v.7 no.11
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    • pp.927-937
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    • 2020
  • Global warming awareness through energy conservation is growing due to the regulatory policies issued by governments and voluntary organization that established carbon emission limits. Transportation is one of the major contributors to carbon emissions. Bike will be simultaneously saving money, getting fit and helping to reduce global warming. Web design has been identified as a key factor for the acceptance and success of the websites and electronic commerce. The purpose of this research is to investigate the effective implementation of the proposed Analytic Hierarchy Process (AHP) technique on a bike case study whose company (Bike Company) is involved in web design for a critical component in the demonstration. Survey research used a variety of data collection methods, with the most common being questionnaires and interviews of some exporters. The research results reveal that the top five key success factors are Good reputation, Transaction security, Ease of use, Promotion, and Diversified choices, which provide the guidelines and directions for decision-makers to design effective websites in the current competitive business scenario. The major findings of this study are suggesting that Internet marketing channels are securing the company's relevance, together with paving the way for methods to increase web traffic.

Health-enhancing Physical Activity Guidelines for Koreans: the Status and Directions for Revision (국민 건강증진을 위한 신체활동 지침)

  • Kim, Wan-Soo
    • Korean Journal of Health Education and Promotion
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    • v.26 no.2
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    • pp.103-117
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    • 2009
  • Objectives: There have been no specific as well as evidence-based physical activity guidelines issued on the governmental level. There just have been physical activity recommendations and guidelines released from governmental agencies or organizations as well as individual researchers and these are not consistent, thereby giving the public and even some professionals quite a confusion. As such, this study was aimed to suggest key factors to include when issuing national physical activity recommendations for Koreans. Methods: Since chronological evolution of modern physical activity recommendations reflects key factors to consider when establishing those recommendations and guidelines, that released for several decades was reviewed. Results: The evolution was found to be based on the basis of strong evidence from both epidemiological and exercise physiology studies and the key concepts of such evolution were feasibility, efficacy, and safety. Conclusion: On the basis of three key factors found in the review process, this study concluded that the upcoming national physical activity guidelines should include the following to maximize the outcomes of the efforts which have long been put by the division of physical activity under the 'New Health Plan 2010'. First, guidelines for achieving health benefits (ie, preventing chronic diseases such as cardiovascular disease, diabetes, and cancers or weight management) as well as improving cardiorespiratory fitness should be included to enhance efficacy. Second, safety measures should be included to enhance safety. Third, various alternative forms of physical activity should be included to enhance feasibility.

Factors governing dynamic response of steel-foam ceramic protected RC slabs under blast loads

  • Hou, Xiaomeng;Liu, Kunyu;Cao, Shaojun;Rong, Qin
    • Steel and Composite Structures
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    • v.33 no.3
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    • pp.333-346
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    • 2019
  • Foam ceramic materials contribute to the explosion effect weakening on concrete structures, due to the corresponding excellent energy absorption ability. The blast resistance of concrete members could be improved through steel-foam ceramics as protective cladding layers. An approach for the modeling of dynamic response of steel-foam ceramic protected reinforced concrete (Steel-FC-RC) slabs under blast loading was presented with the LS-DYNA software. The orthogonal analysis (five factors with five levels) under three degrees of blast loads was conducted. The influence rankings and trend laws were further analyzed. The dynamic displacement of the slab bottom was significantly reduced by increasing the thickness of steel plate, foam ceramic and RC slab, while the displacement decreased slightly as the steel yield strength and the compressive strength of concrete increased. However, the optimized efficiency of blast resistance decreases with factors increase to higher level. Moreover, an efficient design method was reported based on the orthogonal analysis.

Key Factors Affecting Intention to Order Online Food Delivery (OFD)

  • SAN, Sing Su;DASTANE, Omkar
    • The Journal of Industrial Distribution & Business
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    • v.12 no.2
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    • pp.19-27
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    • 2021
  • Purpose: This study investigated the impact of key factors such as service quality, perceived benefit and brand familiarity on a consumer's intention to order online food delivery (OFD). In addition, mediating effect of electronic word of mouth (e-WOM) between relationships among selected key variables and OFD purchase intention is also assessed. Research design, data and methodology: This explanatory, quantitative study employed convenience sampling and collected data through online structured questionnaire from 304 respondents who are users of OFD apps based in greater Klang valley region of Malaysia. The data was then subjected to normality and reliability assessment followed by confirmatory factor analysis, validity assessment and structural equation modelling using IBM SPSS AMOS 24.0. Results: Findings revealed that service quality, perceived benefits and brand familiarity affects purchase intention positively and significantly. Perceived benefits demonstrated highest impact on purchase intention followed by brand familiarity and service quality. Findings also suggest that e-WOM fully mediates relationship between brand familiarity and purchase intention, however, the same was not observed for remaining two variables. Conclusions: The study has enriched OFD literature by investigating impact of selected key factors on purchase intention in the context of OFD. Implications, limitations and future research avenues are then discussed.

Exploratory study on Perceived Critical Sucess Factors for Young Entrepreneurs in the Early Startup Stage (예비 청년창업가들의 핵심성공요인 인식에 대한 탐색적 연구)

  • Bang, JoongHyuk;Park, SangMoon;Shin, JoongKyung
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.9 no.5
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    • pp.247-254
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    • 2014
  • This study explored how early stage entrepreneurs think about key success factors of startup and its impact factors. Previous research on key success factors of startup focused on high technology industry or explored retrospectively main reason of their startup success. However, preparatory entrepreneur who lacks career and social experience has different point of view of startup success, because of their situation which they overcome various problem of entrepreneurial process. This research surveyed key success factors and impact factors of entrepreneurial success based on 905 preparatory entrepreneur. We witnessed that preparatory entrepreneur recognizes various key success factors and found different key success factors according to the attribute of preparatory entrepreneur. We found that man, team startup and non technology related startup in 20s age emphasized procuring superior manpower. But solitary startup and previous career related busienss and long preparation term in 30s age recognized importantly about the entrepreneur's ability. Also, preparatory entrepreneur who considered importantly sales promotion and thorough preparation has different attribute. We can find a unique point that Funding capability was not significant attribute. Finally we suggested implication and further research agenda to foster young entrepreneur based on major findings.

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Empirical Study of Multimodal Transport Route Choice Model in Freight Transport between Mongolia and Korea

  • Ganbat, Enkhtsetseg;Kim, Hwan-Seong
    • Journal of Navigation and Port Research
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    • v.39 no.5
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    • pp.409-415
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    • 2015
  • According to the globalization of world economy on distribution and sales, logistics and transportation parts are playing an important role. Especially, they have to decide what is the key factor of route choice model and how to choose the right transport route in multimodal transport system. By considering the key factors in rote choice model for freight forwarders between Mongolia and Korea, this paper propose 4 main factors: Cost, Delivery time, Freight and Logistics service with 13 sub factors. The importance of factors is surveyed base on AHP through interview with freight forwarders. In results, the empirical insights about current status of Mongolian forwarders are provided with different factors between transportation modes. Expecially, the Time factor is a role factor to choose transport route for air transportation forwarders.