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991.
992.
Md. Ezazul Islam Md. Rafiqul Islam A B M Shawkat Ali 《The Review of Socionetwork Strategies》2016,10(2):105-123
Security of Big Data is a huge concern. In a broad sense, Big Data contains two types of data: structured and unstructured. Providing security to unstructured data is more difficult than providing security to structured data. In this paper, we have developed an approach to provide adequate security to unstructured data by considering types of data and their sensitivity levels. We have reviewed the different analytics methods of Big Data to build nodes of different types of data. Each type of data has been classified to provide adequate security and enhance the overhead of the security system. To provide security to a data node, and a security suite has been designed by incorporating different security algorithms. Those security algorithms collectively form a security suite which has been interfaced with the data node. Information on data sensitivity has been collected through a survey. We have shown through several experiments on multiple computer systems with varied configurations that data classification with respect to sensitivity levels enhances the performance of the system. The experimental results show how and in what amount the designed security suite reduces overhead and increases security simultaneously. 相似文献
993.
Frank Gyamfi-Yeboah Alan J. Ziobrowski 《The Journal of Real Estate Finance and Economics》2010,41(3):339-353
Integration of the capital and mortgage markets is an important step in moving emerging countries toward full economic development.
With data from South Africa, this research examines the incremental contribution of deregulation and the secondary mortgage
market to the integration between the mortgage and capital markets. With deregulation occurring in the early 1980s, the results
indicate that the two markets were fully integrated prior to 2001 when a secondary mortgage market was introduced in South
Africa. However, we also find that the introduction of the secondary mortgage market has significantly reduced constraints
on the supply of mortgage credit. 相似文献
994.
The primary research question examined in this paper is whether ethnic and non-ethnic family firms in the United Kingdom differ in their strategy-making. The paper uses the typology of strategic decision-making produced by Whittington [(1993). What is strategy: and does it matter? New York: Routledge] to derive contrasting predictions of strategy-making by ethnic versus non-ethnic firms. Drawing on a questionnaire study of 76 high-growth family firms, and subsequent in-depth fieldwork with 40 of these, the findings show that the ethnic origin of the controlling family has a significant influence in determining the dominance of a particular strategy paradigm. However, successful high-growth family firms are not associated with any particular school of strategy. The influence of family bonding on strategy-making was greater in ethnic family firms than non-ethnic family firms. The advent of the second generation of South Asians in family firms, and closer integration of immigrant and host communities, has not altered these apparent differences. The findings challenge researchers on family firms to adopt a multiple perspective approach to strategy-making. 相似文献
995.
Process innovations and firm productivity growth 总被引:1,自引:0,他引:1
María Engracia Rochina-Barrachina Juan A. Mañez Juan A. Sanchis-Llopis 《Small Business Economics》2010,34(2):147-166
This article analyses the effect of process innovations on firm total factor productivity growth, explicitly considering the
impact of firm size on the nature of this relationship. In particular, we analyse whether firm size affects the life span
of the impact of process innovations on productivity growth. The data are drawn from a Spanish survey of manufacturing firms
over the period 1991–1998. We use a fully non-parametric methodology based on the concept of stochastic dominance. Our results
show that the implementation of process innovations produces an extra productivity growth both for large and small firms.
However, this productivity growth is more persistent for large than for small firms. 相似文献
996.
In this contribution, we present a virtual voyage through 3D structures generated by chaotic mixing of magmas and numerical simulations with the aim to highlight the power of 3D representations in the understanding of this geological phenomenon. In particular, samples of mixed juveniles from Salina island (Southern Italy) are reconstructed in 3D by serial lapping and digital montage and numerical simulations are performed by using a 3D chaotic dynamical system. Natural and simulated magma mixing structures are visualized by using several multimedia tools including animations and “virtual reality” models. It is shown that magma interaction processes can generate large spatial and temporal compositional heterogeneities in magmatic systems. The same topological structures are observed in both 3D reconstructed rock samples and chaotic numerical simulations, indicating that the mixing of magmas is governed by chaotic dynamics. The use of 3D multimedia models gives the opportunity to penetrate into magma mixing structures and to understand their significance in the context of magma dynamics. Such an approach is very powerful since multimedia tools can strongly capture the attention of the reader bringing him/her into an interactive and memorable geological experience. 相似文献
997.
Elvin Afandi Majid Kermani Fuad Mammadov 《The International Entrepreneurship and Management Journal》2017,13(3):685-716
The paper examines the relationship between social capital and entrepreneurial engagement of individuals in 35 nations from Europe and Asia. To the best of our knowledge, this is the first empirical research that attempts to investigate the influence of three-dimensional social capital concept – trust, networks and norms – on three stages of entrepreneurial process – preference, trial and success – using such large and comprehensive cross-sectional micro data. In general, we find that all three dimensions of social capital matter in the entrepreneurship context, albeit differently. They become beneficial in different ways and at different stages of entrepreneurial involvement. For example, among trust variables, institutional trust in general, and trust in business-oriented and business-supporting actors in particular, exert significant positive effect on entrepreneurial process. Individuals with formal membership in professional associations are more likely to perceive entrepreneurial opportunities, while some close or strong-tie networks might prevent them from progressing in the entrepreneurship ladder. Finally, individual level civic norms appear to be negatively associated with early-stage entrepreneurship, while the success in becoming an entrepreneur is not found to be bound by people’s civic norms. 相似文献
998.
The optimal asset allocation of the main types of pension funds: a unified framework 总被引:1,自引:0,他引:1
Katarzyna Romaniuk 《The GENEVA Risk and Insurance Review》2007,32(2):113-128
The existing literature deals with the optimal investment strategy of defined benefit (DB) or defined contribution (DC) pension
plans. This article’s objective is to compare the optimal policies of different types of pension plans. This is done by first
defining an original framework, which is based on the distinction between the nature of the guarantee—which can be internal
or external—offered by or to a pension fund. This framework allows to establish links between optimization programs of DC,
DB and targeted money purchase schemes. The case of an internal guarantee appears as a standard portfolio insurer’s problem.
The second kind of guarantee, not analyzed in the literature yet with regard to the resulting optimal policy, is characterized
by the existence of an option in the final wealth definition. Four funds are present in the internal guarantee optimal allocation:
the speculative component, the preference independent guarantee- and contribution-hedge terms and the preference dependent
state variable-hedge fund. The external guarantee program, solved with an original method using the principles of standard
options theory, yields an optimal policy incorporating the delta of the option embodied in the final wealth definition. The
conclusion is that the resulting optimal portfolio policy becomes riskier.
相似文献
Katarzyna RomaniukEmail: |
999.
Although the academic interest in ethical mutual fund performance has developed steadily, the evidence to date is mainly sample-specific.
To tackle this critique, new research should extend to unexplored countries. Using this as a motivation, we examine the performance
and risk sensitivities of Canadian ethical mutual funds vis-à-vis their conventional peers. In order to overcome the methodological
deficiencies most prior papers suffered from, we use performance measurement approaches in the spirit of Carhart (1997, Journal of Finance 52(1): 57–82) and Ferson and Schadt (1996, Journal of Finance 51(2): 425–461). In doing so, we investigate the aggregated performance and investment style of ethical and conventional mutual funds and allow for time variation in the funds’ systematic risk. Our␣Canadian
evidence supports the conjecture that any␣performance differential between ethical mutual funds and their conventional peers
is statistically insignificant.
相似文献
1000.
The Economic Value of Water Quality 总被引:1,自引:0,他引:1
Stated preference values for water quality ratings based on the US Environmental Protection Agency National Water Quality
Inventory ratings provide an operational basis for benefit assessment. Iterative choice survey results for a very large, nationally
representative, Web-based panel imply an average valuation of $32 for each percent increase in lakes and rivers in the region
for which water quality is rated “Good.” Valuations are skewed, with the mean value more than double the median. Sources of
heterogeneity in benefit values include differences in responses to average water quality information and the base level of
water quality. Conjoint estimates are somewhat lower than the iterative choice values. The annual economic value of the decline
in inland US water quality from 1994 to 2000 is over $20 billion.
相似文献