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Proposal of Lighting Power Density for Road Lighting (도로종류에 따른 조명전력 허용기준([W/m2]) 제안)

  • Lee, Sang-Jin;Lee, Min-Wook;Kim, Hoon
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.25 no.12
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    • pp.42-47
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    • 2011
  • The design of road lighting is aiming illuminance and luminance requirements for road lighting. In the process, various factors associated with luminaires such as luminous efficacy, light distribution, mounting height, spacing and maintenance factor are considered. However, there has been no restriction on lighting power density. In this study, lighting power density has been comparatively analyzed through a study of related data and a result of measurements on domestic roads. And, it has been analyzed by simulation results for road in which lighting conditions are variable. In terms of the limitation on power density for road lighting, road lighting can be designed using high efficacy lighting systems for energy saving.

The Comparison of Activities of Occupational Safety and Health among Sub-Sectors of Manufacturing Industry (제조업의 업종별 안전보건활동 수준 비교)

  • Kim, Ki-Sik;Rhee, Kyung Yong
    • Journal of the Korean Society of Safety
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    • v.29 no.5
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    • pp.136-145
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    • 2014
  • This article has compared the level of activities of occupational safety and health in workplace among sub-sectors of manufacturing industry in order to set the priority for policy intervention. Data of manufacturing industry in the survey on the current status of occupational safety and health was used with factor analysis and radar graphic method. Authors have categorized sub-sectors of manufacturing industry into four categories, attained group, active group, neglected group, and passive group based on injury rate, level of safety and health activities. The neglected group may be the first target group for occupational safety and health policy guiding some detailed occupational safety and health activities. Limitation of this study is that cross sectional data was analyzed. The long term effect could not be analyzed.

Potential Use of Biopolymer-based Nanocomposite Films in Food Packaging Applications

  • Rhim, Jong-Whan
    • Food Science and Biotechnology
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    • v.16 no.5
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    • pp.691-709
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    • 2007
  • Concerns on environmental waste problems caused by non-biodegradable petrochemical-based plastic packaging materials as well as consumer's demand for high quality food products has caused an increasing interest in developing biodegradable packaging materials using annually renewable natural biopolymers such as polysaccharides and proteins. However, inherent shortcomings of natural polymer-based packaging materials such as low mechanical properties and low water resistance are causing a major limitation for their industrial use. By the way, recent advent of nanocomposite technology rekindled interests on the use of natural biopolymers in the food packaging application. Polymer nanocomposites, especially natural biopolymer-layered silicate nanocomposites, exhibit markedly improved packaging properties due to their nanometer size dispersion. These improvements include increased mechanical strength, decreased gas permeability, and increased water resistance. Additionally, biologically active ingredients can be added to impart the desired functional properties to the resulting packaging materials. Consequently, natural biopolymer-based nanocomposite packaging materials with bio-functional properties have huge potential for application in the active food packaging industry. In this review, recent advances in the preparation and characterization of natural biopolymer-based nanocomposite films, and their potential use in food packaging applications are addressed.

An Interval Algebra-based Modeling and Routing Method in Bus Delay Tolerant Network

  • Wang, Haiquan;Ma, Weijian;Shi, Hengkun;Xia, Chunhe
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.9 no.4
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    • pp.1376-1391
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    • 2015
  • In bus delay-tolerant networks, the route of bus is determinate but its arrival time is indeterminate. However, most conventional approaches predict future contact without considering its uncertainty, which makes a limitation on routing performance. A novel approach is proposed by employing interval algebra to characterize the contact's uncertainty and time-varying nature. The contact is predicted by using the Bayesian estimation to achieve a better routing performance. Simulation results show that this approach achieves a good balance between delivery latency and delivery ratio.

Motion-tracked Speed Dialing for Smartphones

  • Lee, Soong-Hee;Cho, You-Ze
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.8 no.10
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    • pp.3508-3519
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    • 2014
  • The use of a smartphone with one hand has been getting difficult as the size of the smartphone display gets larger. In addition, people handicapped or using one hand for handling other pieces may encounter difficulties to touch exact numbers for calling with their smartphones. Thus, motion-tracked speed dialing can be a good solution for these cases and also an advanced feature applicable in the future network not requiring dedicated Internet connections. The previous study on this feature showed a result with a limitation of using servers connected via Internet connections for solving real-time control issues. Therefore, this paper proposes a scheme for the smartphone dialing on motion-tracked numbers without any servers or Internet connections, and presents the details of its implementation and results.

A Comparative Study on the Orgalime's General Conditions for Turnkey Contracts and FIDIC's Silver Book (ORGALIME의 Turnkey 계약용(契約用) 표준약관(標準約款)과 FIDIC의 Silver Book과의 비교연구(比較硏究))

  • Choi, Myung-Kook;Son, Su-Seok
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.23
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    • pp.129-153
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    • 2004
  • What can easily be concluded is that the Orgalime's General Conditions will be preferred by contractors to the Silver Book. However, it is probable that for some projects the Orgalime's General Conditions will not be acceptable to employers without significant amendment, particularly to such matters as design obligations, limitation of liability, force majeure and possibly the extension of time provisions. It is doubtful, however, whether the Orgalime's General Conditions will prove to be an alternative to the Silver Book. For projects for which the Silver Book was intended, the Orgalime's General Conditions will usually be unacceptable to employers and leaders. Notwithstanding this, the Orgalime's General Conditions is a welcome addition to the ever-growing suite of international contracts. And I strongly suggest that we must prepare our "General Conditions for Turnkey Contracts", etc. reflecting our law and practices as soon as possible.

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A Study on Obligation and Right of the Parties of International Factoring (국제팩토링계약의 당사자의 권리와 의무에 관한 연구)

  • Park, Se-Hun;Han, Ki-Moon
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.43
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    • pp.143-168
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    • 2009
  • International Factoring transaction in Korea is different from that of financially advanced countries in terms of legal system and commercial and financial practices. As for the domestic factoring, Korean factors are only involved in advances often on a with recourse basis. With regard to the international factoring, Korean factors do not accommodate whole account receivables from clients (suppliers) but handle on a selective basis. Among Korean banks, KEXIM (Export and Import Bank of Korea) is sole factor for international transactions. Currently KEXIM and several foreign banks handle factoring provide factoring services with limitation to invoice discounting which is largely extended to large corporate names. Therefore this is far different from factoring in Europe and Americas designed for small exporters with non recourse advances. In respect of legal environment, receivable assignment is subject to debtor' acknowledge or approval of such assignment according to Civil Law Act. To remove the legal obstacles, Korean government have prepared new law which allows factor's own notification of assignment (and thereby reimbursement right) to debtor with some evidences.

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Artificial Neural Network, Induction Rules, and IRANN to Forecast Purchasers for a Specific Product (제품별 구매고객 예측을 위한 인공신경망, 귀납규칙 및 IRANN모형)

  • Jung Su-Mi;Lee Gun-Ho
    • Journal of the Korean Operations Research and Management Science Society
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    • v.30 no.4
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    • pp.117-130
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    • 2005
  • It is effective and desirable for a proper customer relationship management or marketing to focus on the specific customers rather than a number of non specific customers. This study forecasts the prospective purchasers with high probability to purchase a specific product. Artificial Neural Network( ANN) can classily the characteristics of the prospective purchasers but ANN has a limitation in comprehending of outputs. ANN is integrated into IRANN with IR of decision tree program C5.0 to comprehend and analyze the outputs of ANN. We compare and analyze the accuracy of ANN, IR, and IRANN each other.

Analysis of Kinetic Data of Pectinases with Substrate Inhibition

  • Gummadi, Sathyanarayana-N.;Panda, T.
    • Journal of Microbiology and Biotechnology
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    • v.13 no.3
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    • pp.332-337
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    • 2003
  • Enzyme kinetics data play a vital role in the design of reactors and control of processes. In the present study, kinetic studies on pectinases were carried out. Partially purified polymethylgalacturonase (PMG) and polygalacturonase (PG) were the two pectinases studied. The plot of initial rate vs. initial substrate concentration did not follow the conventional Michaelis-Menten kinetics, but substrate inhibition was observed. For PMG, maximum rate was attained at an initial pectin concentration of 3 g/l, whereas maximum rate was attained when the initial substrate concentration of 2.5 g/l of polygalacturonic acid for PG I and PG II. The kinetic data were fitted to five different kinetic models to explain the substrate inhibition effect. Among the five models tested, the combined mechanism of protective diffusion limitation of both high and inhibitory substrate concentrations (semi-empirical model) explained the inhibition data with 96-99% confidence interval.

Fundamental restrictions for the closed-loop control of wind-loaded, slender bridges

  • Kirch, Arno;Peil, Udo
    • Wind and Structures
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    • v.12 no.5
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    • pp.457-474
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    • 2009
  • Techniques for stabilising slender bridges under wind loads are presented in this article. A mathematically consistent description of the acting aerodynamic forces is essential when investigating these ideas. Against this background, motion-induced aerodynamic forces are characterised using a linear time-invariant transfer element in terms of rational functions. With the help of these functions, the aeroelastic system can be described in the form of a linear, time-invariant state-space model. It is shown that the divergence wind speed constitutes an upper bound for the application of the selected mechanical actuators. Even active control with full state feedback cannot overcome this limitation. The results are derived and explained with methods of control theory.