• Title/Summary/Keyword: Key-level distribution

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The Study of Efficient Rekey Interval Allotment for Minimum Cost on Secure Multicast (보안 멀티캐스트 환경에서 최소비용을 위한 효과적인 Rekey Interval 할당에 관한 연구)

  • Baag, Jin-Young;Lee, Goo-Yeon;Lee, Yong
    • Journal of Industrial Technology
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    • v.21 no.A
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    • pp.123-127
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    • 2001
  • This paper proposed for allotment of group key's rekey interval required from secure multicast environment. New group key distribution occurs in two cases: one is periodical update and the other is permitted or unpermitted withdrawal of group member. In later case, the group controller distributes new group key to member except withdrawal member because it can't predict precisely. In former case, the group member who cheated the group can adjust the rekey interval. Using relation between security level, overhead and cost from rekey interval, this paper suggests effective rekey interval allotment through probable performance analysis in large dynamic group.

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Perceptions of Key Stakeholders Towards Sustainable Tourism Development: A Case Study in Mekong Delta, Vietnam

  • VU, Hieu Minh;LAM, Trung Minh;PRABHAKARAN, Sudesh
    • The Journal of Asian Finance, Economics and Business
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    • v.8 no.4
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    • pp.717-726
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    • 2021
  • Tourism is one of the key economic drivers not only in Vietnam but also in the world. This study explores the awareness and perceptions of key stakeholders such as local residents, tourism businesses, and tourists on sustainable tourism development in the Mekong Delta in Vietnam. Both quantitative and qualitative research approaches have been used with the secondary and primary data to provide insights on the subject. The secondary data is from vast sources, including the governmental department of tourism, statistical departments, annual all-level governmental reports, businesses, and others. The primary data is from the survey by questionnaires with 230 enterprises, 720 local residents, and 670 tourists and from the semi-structured and in-depth interviews conducted with local residents, businesses, tourists, local authorities' officers, and especially with 5 experts who are also stakeholders of Mekong Delta tourism. The results will help the related authorities understand the awareness and perceptions of the key stakeholders and deliver valuable information and a concrete delineated roadmap toward sustainable tourism development of the research settings.

A Study on the Recognition Level of Traditional Market Users on Return Intention (소비자의 전통시장에 대한 인식수준이 재 방문의도에 미치는 영향 연구 : 목포지역 소비자를 중심으로)

  • Kim, Pan-Jin
    • The Journal of Industrial Distribution & Business
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    • v.8 no.5
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    • pp.77-85
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    • 2017
  • Purpose - The purpose of this study is to investigate the variables that lead consumers to visit traditional markets and buy market goods. Thus, the current research examined the relationship between satisfaction and return intention as among the factors influencing loyalty. Research design, data, and methodology - This study was conducted to examine the effects of the perceived level of factors on loyalty and how it influenced consumers' visits to traditional markets in 125 adult adolescents and women living in Mok-po area. The results of the questionnaire were obtained. The statistical data of the questionnaire were verified by SPSS. Results - In this study, consumers' perception level of eight loyalty factors can be perceived by the traditional Korean market. The empirical analysis is summarized as follows. First, by selecting five representative variables influencing intention to return to traditional markets, Mok-po area consumers were affected by the intention to revisit according to the intensity of recognition level among these variables. Second, the higher the perceived level of product price, quality of access (accessibility) among the factors that consumers perceive as important factors in visiting traditional markets were heightened. Third, Mokpo residents are aware of the main important factors of visiting the market such as receiving a friendly atmosphere (image) about traditional market, market environment (hygiene and cleanliness), connection with the local economy, and customer service such as kindness, refund and return. These loyalty factors did not affect consumers' intention to revisit. In other words, image, environment, regional economic linkage, and these factors did not have a positive effect on revisit intention. Conclusions - The empirical analysis of this study suggests that factors that directly affect loyalty among the key factors that play a major role in visiting traditional markets should be identified and developed as loyalty factors. It is necessary to identify the key factors influencing the satisfaction and loyalty of traditional market users, and operate a system that systematically and comprehensively manages and evaluates them. In order to do this, the government, the local governments, and related organizations should regularly conduct loyalty and satisfaction surveys on visa recognition levels and establish strategies for dramatic improvement measures.

Molecular Phylogenetic Diversity and Spatial Distribution of Bacterial Communities in Cooling Stage during Swine Manure Composting

  • Guo, Yan;Zhang, Jinliang;Yan, Yongfeng;Wu, Jian;Zhu, Nengwu;Deng, Changyan
    • Asian-Australasian Journal of Animal Sciences
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    • v.28 no.6
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    • pp.888-895
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    • 2015
  • Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and subsequent sub-cloning and sequencing were used in this study to analyze the molecular phylogenetic diversity and spatial distribution of bacterial communities in different spatial locations during the cooling stage of composted swine manure. Total microbial DNA was extracted, and bacterial near full-length 16S rRNA genes were subsequently amplified, cloned, RFLP-screened, and sequenced. A total of 420 positive clones were classified by RFLP and near-full-length 16S rDNA sequences. Approximately 48 operational taxonomic units (OTUs) were found among 139 positive clones from the superstratum sample; 26 among 149 were from the middle-level sample and 35 among 132 were from the substrate sample. Thermobifida fusca was common in the superstratum layer of the pile. Some Bacillus spp. were remarkable in the middle-level layer, and Clostridium sp. was dominant in the substrate layer. Among 109 OTUs, 99 displayed homology with those in the GenBank database. Ten OTUs were not closely related to any known species. The superstratum sample had the highest microbial diversity, and different and distinct bacterial communities were detected in the three different layers. This study demonstrated the spatial characteristics of the microbial community distribution in the cooling stage of swine manure compost.

Analysis of the Input of Education and Innovation on Economic Growth in Kazakhstan

  • KIREYEVA, Anel A.;KUANDYK, Zhassulan;KREDINA, Anna A.;KANGALAKOVA, Dana;DOSZHAN, Raigul
    • Journal of Distribution Science
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    • v.21 no.1
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    • pp.23-31
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    • 2023
  • Purpose: this study is aimed at assessing the contribution of education and innovation to the economic growth of Kazakhstan, the correlation between them is checked based on two levels on a national scale and a regional scale. Based on the literature review, it was revealed that in the vastness of the scientific community, there are many views concerning the influence of educational and innovative factors on economic growth. Research design, data and methodology: the research methodology is divided into two levels, at the first level, a correlation analysis is carried out between key factors and the economic growth of the country (GDP), at the second level, the same factors are analyzed, but the impact on the economic growth of the region (GRP) is estimated. Statistical data on educational and innovation potential is taken from the Bureau of National Statistics for the period 2003-2021. Results: in this study, it was revealed that the economic development of regions could be influenced by such indicators that cannot affect the entire state in aggregate and vice versa. In addition, the correlation analysis results showed that investments in innovations affect economic growth at the country and the regional level. Conclusions: based on the results of the assessment of educational and innovative potential, policy recommendations and further research in this area were proposed.

Optimization of the anti-snow performance of a high-speed train based on passive flow control

  • Gao, Guangjun;Tian, Zhen;Wang, Jiabin;Zhang, Yan;Su, Xinchao;Zhang, Jie
    • Wind and Structures
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    • v.30 no.4
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    • pp.325-338
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    • 2020
  • In this paper, the improvement of the anti-snow performance of a high-speed train (HST) is studied using the unsteady Reynolds-Averaged Navier-Stokes simulations (URANS) coupled with the Discrete Phase Model (DPM). The influences of the proposed flow control scheme on the velocity distribution of the airflow and snow particles, snow concentration level and accumulated mass in the bogie cavities are analyzed. The results show that the front anti-snow structures can effectively deflect downward the airflow and snow particles at the entrance of the cavities and alleviate the strong impact on the bogie bottom, thereby decrease the local accumulated snow. The rotational rear plates with the deflecting angle of 45° are found to present well deflecting effect on the particles' trajectories and force more snow to flow out of the cavities, and thus significantly reduce the accretion distribution on the bogie top. Furthermore, running speeds of HST are shown to have a great effect on the snow-resistance capability of the flow control scheme. The proposed flow control scheme achieves more snow reduction for HST at higher train's running speed in the cold regions.

Do Firm and Bank Level Characteristics Matter for Lending to Firms during the Financial Crisis?

  • Lee, Mihye
    • The Journal of Industrial Distribution & Business
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    • v.9 no.5
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    • pp.37-46
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    • 2018
  • Purpose - This paper explores the determinants of bank lending to firms during and after the global financial crisis using firm- and bank-level data to answer the questions what caused the contraction of lending to firms despite the loosening monetary policy during this crisis period. Research design, data, and methodology - We investigate the effects of the monetary policy that followed the global financial crisis on firms borrowing. We use a dynamic panel model to address how firms lending respond to monetary policy. The data are obtained from CRETOP and we consider the manufacturing sector for the analysis to control for unobserved heterogeneity such as industry-specific shocks. Results - The findings from the empirical analysis suggest that both bank- and firm-level characteristics are significant determinants of bank lending. Especially, we find that corporate risk, measured by default risk, is one of the key factors that led to a decline in lending during the crisis. Conclusions - This paper shows that companies borrow more from liquid banks, and high bank capital can also contribute to an increase in a firm's borrowing from banks. Especially, the results confirm that the default rate measured at the firm level has increased during and after the global financial crisis, which implies that default risk interplays with other firm and bank-level characteristics.

Geographic Distribution and Epidemiology of Lung Cancer During 2011 in Zhejiang Province of China

  • Lin, Xia-Lu;Chen, Yan;Gong, Wei-Wei;Wu, Zhao-Fan;Zou, Bao-Bo;Zhao, Jin-Shun;Gu, Hua;Jiang, Jian-Min
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.13
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    • pp.5299-5303
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    • 2014
  • Background: To explore etiology for providing scientific clues for the prevention of lung cancer. Materials and Methods: Data for lung cancer incidence and meteorological geographic factors from 25 counties in Zhejiang province of China during 2011 were studied. Stepwise multiple regression and correlation analysis were performed to analyze the geographic distribution and epidemiology of lung cancer. Results: 8,291 new cases (5,998 in males and 2,293 females) of lung cancer during 2011 in Zhejiang province were reported in the 25 studied counties. Reported and standardized incidence rates for lung cancer were 58.0 and 47.0 per 100,000 population, respectively. The incidence of lung cancer increased with age. Geographic distribution analysis shows that the standardized incidence rates of lung cancer in northeastern Zhejiang province were higher than in the southwestern part, such as in Nanhu, Fuyang, Wuxing and Yuyao counties, where the rates were more than 50 per 100,000 population. In the southwestern Zhejiang province, for instance, in Yueqing, Xianju and Jiande counties, the standardized incidence rates of lung cancer were lower than 37 per 100,000 population. Spearman correlation tests showed that forest coverage rate, air quality index (AQI), and annual precipitation level are associated with the incidence of lung cancer. Conclusions: Lung cancer in Zhejiang province shows obvious regional differences. High incidence appears associated with low forest coverage rate, poor air quality and low annual precipitation. Therefore, increasing the forest coverage rate and controlling air pollution may play an important role in lung cancer prevention.

A Study on the Development and Measurement of Logistics Partners Cooperation Index(LPCI): Focused on the Joint Logistics (물류협력지수의 개발 및 측정에 관한 연구: 공동물류사업을 중심으로)

  • Suh, Sang-Sok;Song, Gwang-Suk;Park, Jong-Woo
    • Journal of Distribution Science
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    • v.14 no.6
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    • pp.107-118
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    • 2016
  • Purpose - Over 90% of Domestic logistics industry is small enterprise and they are experiencing growth stagnation due to price-based competition structure rather than constructing logistics service of high added value. In order to get over this situation and pursue the development of logistics industry, strengthening its competitiveness, through inter-enterprise cooperative network build-up, would be a key alternative. Therefore, in this study, an index for measuring inter-enterprise cooperation level of Joint logistics business will be developed as a typical collaborative business model in logistics industry. Moreover, a strengthening competitiveness method suggests a developmental step and a key management index to mature in logistics industry. Research Design, Data, Methodology - This study is an index development research for measuring inter-enterprise cooperation level of logistics industry. Such a level was measured by performing a survey by targeting enterprises that participated in Joint logistics business. The targeting enterprises are typical cooperative models in logistics industry. Measurement items were developed which were based on the presented items in existing research. Question items were composed of selection type questions as answering Yes/No. They measures implementation status of corporate activity and detailed activity items measuring qualitative level. Total samples were based on 116 enterprise samples including 90 logistics enterprises and 26 shippers. In addition, by evaluating the importance for Joint logistics business recognition with personnel working level, the weight of measuring variable was extracted. This study has built an assessment tools (LPCI) on Joint logistics business cooperation level in a situation where there are no previous studies on joint logistics business, this study is meaningful for other studies. Results - As a result of analyzing LPCI presented in this study, the score of logistics enterprise was represented as 59.9 points based on full score of 100 points and that of shippers as 47.2 points and cooperation level among enterprises participated in Joint logistics business was revealed to be very low. In particular, as a result of measuring the importance between logistics enterprise and shippers, the difference by each measurement standard was represented among those enterprises. This difference is considered to be a key factor that cooperative operational conformity between logistics enterprises and shippers is represented to be low. Conclusions - As most joint logistics business, being promoted at present, is sharing facility and information with joint logistics business, it is hard to find such a joint logistics business in reality based on cooperative business model in main cooperation agents. Therefore, competitiveness of logistics industry could be strengthened by promoting joint logistics business based on their mutual cooperation among enterprises. In other words, it is to secure sustainable competitiveness of joint logistics business together with creation of new market by inter-enterprise cooperation based on integration of basic logistics business.

Reliability of numerical computation of pedestrian-level wind environment around a row of tall buildings

  • Lam, K.M.;To, A.P.
    • Wind and Structures
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    • v.9 no.6
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    • pp.473-492
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    • 2006
  • This paper presents numerical results of pedestrian-level wind environment around the base of a row of tall buildings by CFD. Four configurations of building arrangement are computed including a single square tall building. Computed results of pedestrian-level wind flow patterns and wind speeds are compared to previous wind tunnel measurement data to enable an assessment of CFD predictions. The CFD model uses the finite-volume method with RNG $k-{\varepsilon}$ model for turbulence closure. It is found that the numerical results can reproduce key features of pedestrian-level wind environment such as corner streams around corners of upwind building, sheltered zones behind buildings and channeled high-speed flow through a building gap. However, there are some differences between CFD results and wind tunnel data in the wind speed distribution and locations of highest wind speeds inside the corner streams. In locations of high ground-level wind speeds, CFD values match wind tunnel data within ${\pm}10%$.