• Journal of Forest and Environmental Science
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• 제30권4호
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• pp.342-350
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• 2014

Rural people of Sudan are endowed with a deep knowledge concerning the utilization of different tree species. However research on the local knowledge related to tree species utilization still lacks adequate attention. The study objectives were to identify the existing local knowledge related to the utilization of the tree species and the existing threats to the availability of the trees. A total of 300 respondents were selected randomly from Rashad district in Nuba Mountains in 2011. Semi-structured interview, direct observation, group discussion, preference ranking and direct matrix ranking were used to collect the data. The study results revealed that people of Nuba Mountains utilize different tree species for food, medicinal purposes, fodder, firewood, construction and cultural ceremonies. The study results also indicated that the availability of trees is negatively influenced by firewood collection, agricultural expansion, drought, overgrazing and charcoal production. The study concluded that local knowledge has crucial role in tree species utilization in Nuba Mountains. Further researches to document and substantiate the local knowledge on useful tree species are highly recommended.

• Journal of Construction Engineering and Project Management
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• 제7권1호
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• pp.30-36
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• 2017

Most local agencies such as counties and small cities continuously express difficulties in making technically and financially defensible decisions on their pavement infrastructure maintenance and rehabilitation. Unlike pavement systems managed by state highway agencies, the total lane-miles of many local pavements are significantly short and they are managed by a limited number of staff who typically have multiple responsibilities. Most local agencies also do not have historical pavement performance data and the lack of a systematic decision making framework exacerbates the problem. A structured framework and an easily accessible decision support tool that reflects their local requirements, practices and operational conditions would greatly assist them in making consistent and defensible decisions. This study fills this gap by developing a systematic pavement treatment selection framework and a spreadsheet based tool for local agencies. It is expected that the proposed framework will significantly help local agencies to improve their pavement asset management practices at the project level.

• Journal of Communications and Networks
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• 제14권4호
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• pp.385-395
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• 2012

This paper tackles the problem of generating shared secret keys based on the physical characteristics of the wireless channel. We propose intelligent quantization mechanisms for key generation, achieving high secret bits generation rate. Moreover, some practical issues affecting the performance of the key generation mechanism are deeply investigated. Mainly, we investigate the effects of delay and mobility on the performance and we enhance the key generation mechanism accordingly. As a result, this paper presents a framework towards robust key generation from multipath wireless channels.

• 천문학회지
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• 제29권spc1호
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• pp.129-131
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• 1996

The results on the deep low dispersion (1250 ${\AA}$/mm at $H_r, $30^{\circ}$ < I < $165^{\circ}$, $195^{\circ}$ < I < $210^{\circ}$, [b] < $5^{\circ}$; 7000${\AA}$/mm at A band, $50^{\circ}$ < I < $115^{\circ}$, b=$0^{\circ}$, b=${\pm}3.5^{\circ}$) spectral surveys of the MILKY WAY are presented. More than 2250 carbon stars were identified among them 1440 new ones. The C/M5+ ratio increases from 0.02 to 0.3 when longitude varies from $30^{\circ}$ to $210^{\circ}$. On the basis of A GENERAL CATALOG OF GALACTIC COOL CARBON STARS the surface distribution of carbon stars has been studied.

• Natural Product Sciences
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• 제15권1호
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• pp.22-26
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• 2009

Phytochemical investigation of the roots of Echiochilon fruticosum resulted in the isolation of two naphthoquinone derivatives. Compound 1 was identified as anhydroalkanin while compound 2 was identified as a new derivative 5-hydroxy 8-methoxy 2-(4-methylpent-1,3-dienyl) naphthalene-1,4-dione named as echiochiloquinone. In addition, caffeic acid 3, caffeic acid methyl ester 4 were isolated. The structures were determined by physical, chemical and spectral methods. The anti-inflammatory activity of the root extracts and compound 2 was evaluated utilizing both cotton pellet-induced and carragenin-induced rat paw edema. The ulcerogenic effect was also studied.

• Journal of the Korean Statistical Society
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• 제34권1호
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• pp.49-60
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• 2005

In this paper we introduce a nonparametric method for estimating the probability density function of detection distances in line transect sampling. The estimator is obtained using a frequency histogram density estimation method. The asymptotic properties of the proposed estimator are derived and compared with those of the kernel estimator under the assumption that the data collected satisfy the shoulder condition. We found that the asymptotic mean square error (AMSE) of the two estimators have about the same convergence rate. The formula for the optimal histogram bin width is derived which minimizes AMSE. Moreover, the performances of the corresponding k-nearest-neighbor estimators are studied through simulation techniques. In the absence of our knowledge whether the shoulder condition is valid or not a new semi-parametric model is suggested to fit the line transect data. The performances of the proposed two estimators are studied and compared with some existing nonparametric and semiparametric estimators using simulation techniques. The results demonstrate the superiority of the new estimators in most cases considered.

• Asian Journal of Innovation and Policy
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• 제2권2호
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• pp.240-264
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• 2013

The study compares network structures that emerged in three inter-organisational projects set up under the MSC Malaysia initiative by the Government of Malaysia. These consortia are seen as policy-driven inter-organisational networks and, with data collected through interviews; the links among the organisations are mapped to gain an understanding of the structures that emerged in these networks. The findings provide lessons for other emerging countries that are embarking on similar projects i.e. cluster-oriented developments with policy-driven inter-organisational networks. These findings are seen as particularly useful when emerging countries invest in technology-related projects and invite multinational companies to work together with local firms.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제7권9호
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• pp.2194-2212
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• 2013

The multicast routing architectures have become indispensable due to the increasing needs for extreme communication services anywhere and anytime. The most recent approaches are called hierarchical and fully distributed, what have been proposed by O. Said et al. in a previous work. These proposed architectures were introduced to enhance the service-centric approach. In this paper, NS2 is used to build a simulation environment to test the hierarchical and the fully distributed multicast architectures as regards the service-centric one. The results of simulation show that the performance of the hierarchical and the fully distributed architectures outperforms the service-centric architecture. Furthermore, the fully distributed architecture is found to have the best performance.

• Journal of Species Research
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• 제7권4호
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• pp.315-322
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• 2018

Based on morphological observation, we identified nine ciliates previously unrecorded in Korea, Euplotidium itoi Ito, 1958, Anteholosticha verrucosa (Foissner & Schade, 2000) Berger, 2008, Holostichides dumonti Foissner, 2000, Amphisiella australis Blatterer & Foissner, 1988, Terricirra matsusakai Berger & Foissner, 1989, Uroleptoides binucleatus binucleatus Hemberger, 1985, Uroleptoides magnigranulosus (Foissner, 1988) Berger, 2008, Leptopharynx costatus gonohymen Omar & Foissner, 2012, Pseudochilodonopsis mutabilis Foissner, 1981, from three sites in Korea, which were isolated from three environmental samples, consisting of one seawater and two soil samples. These ciliates were assigned to three classes, five orders, five families, and eight genera. In this study, we provide photographs and brief descriptions and remarks of the nine species.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1996년도 봄 학술발표회 논문집
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• pp.182-189
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• 1996

The focus of this study is on the problem of the design of structure of undetermined topology. This problem has been regarded as being the most challenging of structural optimization problems, because of the difficulty of allowing topology to change. Conventional approaches break down when element sizes approach to zero, due to stiffness matrix singularity. In this study, a novel nonlinear Programming formulation of the topology Problem is developed and examined. Its main feature is the ability to account for topology variation through zero element sizes. Stiffness matrix singularity is avoided by embedding the equilibrium equations as equality constraints in the optimization problem. Although the formulation is general, two dimensional plane elasticity examples are presented. The design problem is to find minimum weight of a plane structure of fixed geometry but variable topology, subject to constraints on stress and displacement. Variables are thicknesses of finite elements, and are permitted to assume zero sizes. The examples demonstrate that the formulation is effective for finding at least a locally minimal weight.