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Structural Characteristics of Cell Walls of Forage Grasses - Their Nutritional Evaluation for Ruminants - - Review -

  • Iiyama, Kenji;Tuyet Lam, Thi Bach
    • Asian-Australasian Journal of Animal Sciences
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    • v.14 no.6
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    • pp.862-879
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    • 2001
  • The walls of all higher plants are organized as a cellulosic, fibrillar phase embedded in a matrix phase composed of non-cellulosic polysaccharides, some proteins and, in most secondary walls, lignin. At the effective utilization of plant biomass, qualitative and quantitative analyses of plant cell walls are essential. Structural features of individual components are being clarified using newly developed equipments and techniques. However, "empirical" procedures to elucidate plant cell walls, which are not due to scientific definition of components, are still applied in some fields. These procedures may give misunderstanding for the effective utilization of plant biomass. In addition, interesting the investigation of wall organization is moving towards not only qualitatively characterisation, but also quantitation of the associations between wall components. These involve polysaccharide-polysaccharide and polysaccharide-lignin cross-links. Investigation of the associations is being done in order to understand the chemical structure, organization and biosynthesis of the cell wall and physiology of the plants. Procedures for qualitative and quantitative analyses based on the definition of cell wall components are reviewed focussing in nutritional elucidation of forage grasses by ruminant microorganisms.

Seismic performance of eccentrically braced frames with high strength steel combination

  • Lian, Ming;Su, Mingzhou;Guo, Yan
    • Steel and Composite Structures
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    • v.18 no.6
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    • pp.1517-1539
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    • 2015
  • Eccentrically braced frames (EBFs) often use conventional steel with medium yield strength. This system requires structural members with large cross-sections for well seismic behavior, which leads to increased material costs. In eccentrically braced frames with high strength steel combination (HSS-EBFs), links use Q345 steel (specified nominal yield strength 345 MPa), braces use Q345 steel or high strength steel while other structural members use high strength steel (e.g., steel Q460 with the nominal yield strength of 460 MPa or steel Q690 with the nominal yield strength of 690 MPa). For this approach can result in reduced steel consumption and increased economic efficiency. Several finite element models of both HSS-EBFs and EBFs are established in this paper. Nonlinear hysteretic analyses and nonlinear time history analyses are conducted to compare seismic performance and economy of HSS-EBFs versus EBFs. Results indicate that the seismic performance of HSS-EBFs is slightly poorer than that of EBFs under the same design conditions, and HSS-EBFs satisfy seismic design codes and reduce material costs.

A study on the functions of headings (표목의 기능에 관한 연구)

  • 김태수
    • Journal of the Korean Society for information Management
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    • v.12 no.2
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    • pp.9-35
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    • 1995
  • Locating function of a particular item is more of added entry than a main entry heading. This function was expanded especially in the machine readable cataloging by introducing the control number and standard bibliographic number. Assembling function of the main entry heading is on a level with that of cross reference and notes, added entries, uniform headings. Links among all variant forms of a heading in hypercatalog will be made for collocating of all publications of a given author. The link of bibliographic records in this catalog can be freed from the dependence on standardized heading form. The function of the catalog is not affected even though by abandoning the concept of main entry heading. Further efforts should be made to raise users' finding opportunities through expansion of acces points and linking devices among related records.

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Posttraumatic Growth, Dyadic Adjustment, and Quality of Life in Breast Cancer Survivors and Their Husbands (유방암 생존자 부부의 외상 후 성장과 부부적응, 삶의 질)

  • Song, Seunghee;Ryu, Eunjung
    • Journal of Korean Academy of Nursing
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    • v.44 no.5
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    • pp.515-524
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    • 2014
  • Purpose: The purpose of this study was to identify whether the couple perceived breast cancer as a traumatic event, to evaluate the association among posttraumatic growth, dyadic adjustment, and quality of life and to explore the predictors affecting quality of life of the couple. Methods: A cross-sectional comparative survey design was utilized. Participants were 57 couples recruited from a national cancer center in Korea. Data were analyzed using paired t-test, McNemar test and independent t-test. On the basis of variables found to be significantly associated with quality of life, multiple regression was used to examine the simultaneous influence of multiple predictors. Results: Breast cancers survivors and spouses perceived breast cancer as a traumatic event (43.9% and 24.6%, respectively). The global quality of life was explained by perception as trauma (${\beta}$= -19.79) and posttraumatic growth (${\beta}$=0.46) in survivors, and perception as trauma (${\beta}$= -18.81) and dyadic adjustment (${\beta}$=0.53) in spouses. Conclusion: Results suggest that future research should use qualitative methods to evaluate why contemplating reasons for cancer contributed to posttraumatic growth, examine other potential predictors of quality of life such as dyadic adjustment and intimacy, and identify links between posttraumatic growth and other psychological outcomes such as distress and well-being, using prospective analyses.

Structure-property relations for polymer melts: comparison of linear low-density polyethylene and isotactic polypropylene

  • Drozdov, A.D.;Al-Mulla, A.;Gupta, R.K.
    • Advances in materials Research
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    • v.1 no.4
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    • pp.245-268
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    • 2012
  • Results of isothermal torsional oscillation tests are reported on melts of linear low density polyethylene and isotactic polypropylene. Prior to rheological tests, specimens were annealed at various temperatures ranging from $T_a$ = 180 to $310^{\circ}C$ for various amounts of time (from 30 to 120 min). Thermal treatment induced degradation of the melts and caused pronounced decreases in their molecular weights. With reference to the concept of transient networks, constitutive equations are developed for the viscoelastic response of polymer melts. A melt is treated as an equivalent network of strands bridged by junctions (entanglements and physical cross-links). The time-dependent response of the network is modelled as separation of active strands from and merging of dangling strands with temporary nodes. The stress-strain relations involve three adjustable parameters (the instantaneous shear modulus, the average activation energy for detachment of active strands, and the standard deviation of activation energies) that are determined by matching the dependencies of storage and loss moduli on frequency of oscillations. Good agreement is demonstrated between the experimental data and the results of numerical simulation. The study focuses on the effect of molecular weight of polymer melts on the material constants in the constitutive equations.

Structure and Property Modification of Bimodal Molecular Weight Distribution Polyethylene by Electron Beam Irradiation

  • Lee, Sang-Man;Jeon, Hye-Jin;Choi, Sun-Woong;Song, Hyun-Hoon;Nho, Young-Chang;Cho, Kyu-Cheol
    • Macromolecular Research
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    • v.14 no.6
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    • pp.640-645
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    • 2006
  • Polyethylene of bimodal molecular weight distribution was irradiated with an electron beam. The thermal and mechanical properties were examined by DSC, small and wide angle X-ray scattering and static tensile test according to the crystal morphology of the irradiated samples. The crystal morphology change upon irradiation, as revealed by wide angle X-ray scattering, correlated well with the changes in melting enthalpy, whereas the lamellar thickness and the amorphous gap thickness remained virtually unchanged at irradiation doses up to 500 kGy. Crosslinks in the crystal domains became evident at an energy level of 250 kGy, resulting in reduced crystallinity and crystal size of the (110) and (200) planes. The samples became stiff and brittle with increased irradiation dose, which seem to be more relevant to the amount of cross links than the crystal morphology changes.

Cascading Citation Expansion

  • Chen, Chaomei
    • Journal of Information Science Theory and Practice
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    • v.6 no.2
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    • pp.6-23
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    • 2018
  • Digital Science's Dimensions is envisaged as a next-generation research and discovery platform for more efficient access to cross-referenced scholarly publications, grants, patents, and clinical trials. As a new addition to the growing open citation resources, it offers opportunities that may benefit a wide variety of stakeholders of scientific publications, from researchers and policy makers to the general public. In this article, we explore and demonstrate some of the practical potentials in terms of cascading citation expansions. Given a set of publications, the cascading citation expansion process can be iteratively applied to a set of articles so as to extend the coverage to more and more relevant articles through citation links. Although the conceptual origin can be traced back to Garfield's citation indexing, it has been largely limited, until recently, to the few who have unrestricted access to a citation database that is large enough to sustain such iterative expansions. Building on the open application program interface of Dimensions, we integrate cascading citation expansion functions in CiteSpace and demonstrate how one may benefit from these new capabilities. In conclusion, cascading citation expansion has the potential to improve our understanding of the structure and dynamics of scientific knowledge.

The Role of Northeast Asian Cities in a Global Urban Network

  • Rozman, Gilbert
    • Journal of the Korean Regional Science Association
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    • v.15 no.2
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    • pp.5-19
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    • 1999
  • This paper identifies five factors that limited urban network formation in Northeast Asia over the past half millennium, questions the extent to which they are being overcome in the 1990s, and sketches a network of cities that could boost regionalism. It briefly traces the historical evolution of these factors, including comparisons with European integration, while focusing primarily on the policies of the 1990s that have affected their continuing role. First is the factor of closed national markets with weak regional integration. Second is the preeminence of administrative means of integration over commercial ones. Third is the character of localism, shackled by overcentralization and weak cross-border linkages. Fourth is the limited nature of internationalism, dominated by state catch-up policies with one-sided global involvement. Fifth is a lack of regional consciousness. Just as national urban integration was essential for regional networks to form, without regional integration it is difficult to contemplate Northeast Asian cities taking their rightful place in a global urban network. After noting the failures of the 1990s, the paper points to the potential role as dragon's heads for sub-regional urban networks of potential front-line cities: Tumen, Sapporo, Irkutsk, and what I call the Amur triangle. Also of interest are how the capitals of Beijing, Moscow, Seoul, and Tokyo will adjust to a transformed urban network. After all, their current skepticism must be overcome with a program that links the benefits on all sides in order to build trust in regionalism. This requires internationalism and symbols of a balanced approach to each country's needs.

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A Study on the Traffic Effect Zone and Application of Road Occupying Construction (도로 공사중의 교통영향권역 설정 및 적용성에 관한 연구)

  • Lee, Ju-Ho;Lee, Young-Woo;Lim, Chae-Moon
    • Journal of the Korean Society of Industry Convergence
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    • v.6 no.2
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    • pp.131-139
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    • 2003
  • The links operating interrupted flow are intend to yield the traffic between the out flow and inflow part effect zone of street section, we build the delay model using the time gap between under construction and not. We review the applicability of interrupted flow, and thus we can put this data to practical use as the basis data to compute the inducement charge for traffic delay. Also building about traffic effect zone of interrupted flow wouldn't produce at the section beside occupying roads and construction cross section, thus we must review the plan to minimize traffic delay by the construction occupying road. In future there must be advanced the incomplete in this study, and groping for the various alternatives to minimize the traffic delay by the road occupying construction, with developing the various sets of detailed analyzing models, that is analysis on the street strength, crossroads geometrical forms of crossroads, public traffics, pedestrians, occupying types.

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A MAC Protocol for Link Maintenance in Multichannel Cognitive Radio Ad Hoc Networks

  • Li, Jingye;Luo, Tao;Gao, Jing;Yue, Guangxin
    • Journal of Communications and Networks
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    • v.17 no.2
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    • pp.172-183
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    • 2015
  • To provide an efficient link maintenance approach, we propose a cross layer medium access control (LM-MAC) protocol for multichannel cognitive radio ad hoc networks. Link establishment and reliable transmission are two key problems for a perfect link maintenance mechanism. Since the cognitive user (CU) pairs have to reestablish their links each frame, in the proposed MAC protocol, three different access modes are designed to guarantee transmission efficiency in continuous frames. To enhance the transmission reliability, each CU will create a father spectrum list (FSL) after joining in the network. FSL is divided into three groups of sub-channels with different functions to compensate the packet loss caused by the primary users' appearance and the deep fading. Meanwhile, since the transmitter and the receiver will share the same FSL, periodical cooperative sensing is adopted to further optimize the former problem. Finally, compared with the existing opportunistic multichannel (OMC)-MAC protocol, the proposed LM-MAC protocol achieves better system performance in terms of saturation throughput, continuity and access delay.