• Title/Summary/Keyword: Limited use

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Grain Yield and Water Use Efficiency as Affected by Irrigation at Different Growth Stages

  • Kim, Wook-Han;Hong, Byung-Hee;Ryu, Yong-Hwan
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.44 no.4
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    • pp.330-338
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    • 1999
  • Extensive research has been conducted on effects of drought stress on growth and development of soybean but information is rather restricted on the limited-irrigation system by way of precaution against a long-term drought condition in the future. The experiment for limited-irrigation was conducted in transparent vinyl shelter at Asian Vegetable Research and Development Center (AVRDC), Taiwan in 1997. Two soybean varieties, Hwangkeum and AGS292, improved in Korea and AVRDC, respectively were used for this experiment. The relationships between normalized transpiration rate (NTR) and fraction of transpirable soil water (FTSW) in both varieties were similar that the NTR was unchanged until FTSW dropped to about 0.5 or 0.6. At FTSW less than those values, NTR declined rapidly. Days required to harvest in both varieties were significantly prolonged at IR6 treatment compared to any other treatments. Daily mean transpiration rate was significantly higher at IR5 treatment, as averaged over varieties. Similarly, water use efficiency was also high at 1R5 treatment. In both varieties, seed yield was the greatest at the IR5 treatment, as compared to any other limited-irrigation treatments, due to the increased seed number and high transpirational water use efficiency. The indices of input water and seed yield for the different limited-irrigation treatments against control indicated that Hwangkeum produced 59.6% or 60.7% of seed yield using 36.1% or 44.9% of input water, as compared to control, by irrigation at only R5 or R6 stages, respectively. The AGS292 produced 56.1% of seed yield with 35.4% of input water of control, when irrigated at R5 stage. The results of this study have elucidated that the limited irrigation at R5 stage in soybean can be minimized yield loss with such small quantity of water under the environment of long-term drought stress and the expected shortage of agricultural water in the future.

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Look-ahead Preview Control with Limited Bandwidth Active Suspension - Application to Tracked Vehicle Systems (제한 대역폭을 가진 능동 현가 장치에 대한 Look-ahead 예견 제어-궤도 차량에의 응용)

  • Ryu, Seong-Pil;Park, Young-Jin;Park, Youn-Sik
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2005.11a
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    • pp.209-212
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    • 2005
  • The look-ahead preview control with the use of limited bandwidth active suspensions is presented. Both a linearized racked vehicle model and a complex nonlinear model based on a commercial multibody dynamic program are used to verify the performance of preview control. The performance of the preview control system is evaluated on the ride quality which is estimated from the acceleration of the driver position. Due to the practical advantages associated with the use of limited bandwidth active control in comparison with full bandwidth systems, the results are considered important to the future development of active tracked vehicle suspensions.

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An Empirical Study on the Determinants of Intention to Use B2B e-Marketplace

  • An, Youngsin;Yang, Haesool
    • Journal of the Korea Society of Computer and Information
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    • v.22 no.9
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    • pp.155-161
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    • 2017
  • As the e-marketplace becomes the core of management activities, researches on motivation, transaction type, strategy, satisfaction, risk management, performance evaluation, etc. have been actively studied, but the factors influencing actual utilization have not been fully. Especially, the factors that affect the intention of the users are limited without consideration of internal environment, external environment, e-marketplace characteristics such as operating rules, characteristics of the company to be used. In order to derive the determinants of B2B e-marketplace use, this study was conducted to examine the relationship between internal environment, external environment, e-marketplace characteristics as independent variables, intention of use as dependent variable, participation qualification, The results were as follows. First, the previous study limited the determinants of intention to use to either internal or external, but this study presented an integrated model that considers both factors. Second, the characteristics of companies participating in e-marketplace were identified by using participation qualification and activity scope as control variables.

EffECTIVE PARTICULATES REDUCTION IN DIESEL ENGINES THROUGH THE USE OF FUEL CATALYSED PARTICULATE FILTERS

  • Vincent, M.-W.;Richards, P.-J.;Rogers, T.-J.
    • International Journal of Automotive Technology
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    • v.3 no.1
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    • pp.1-8
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    • 2002
  • There is Increasing world-wide interest in diesel particulate filters (DPF) because of their proven effectiveness in reducing exhaust smoke and particulate emissions. Fine particulates have been linked to human health . DPF use requires a means to secure the bum-out of the accumulated soot, a process called regeneration. If this is not achieved, the engine cannot continue to operate. A number of techniques are available, but most are complex, expensive or have a high electrical demand. The use of fuel additives to catalyse soot bum-out potentially solves the problem of securing regeneration reliably and at low cost. Work on organo-metallic fuel additives has shown that certain metals combine to glove exceptional regeneration performance. Best performance was achieved with a combination of iron and strontium based compounds. Tests were carried out un a bed engine and on road vehicles, which demonstrated effective and reliable regeneration from a tow dose fuel additive, using a single passive DPF. No control valves, flow diverters. heaters or other devices were employed to assist regeneration. Independent particle size measurements showed that there were no harmful side effects from the use of the iron-strontium fuel additive.

On Power Allocation Schemes for Bi-directional Communication in a Spectrum Sharing-based Cognitive Radio System

  • Kim, Hyungjong;Wang, Hanho;Hong, Daesik
    • IEIE Transactions on Smart Processing and Computing
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    • v.3 no.5
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    • pp.285-297
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    • 2014
  • This paper presents the results of an investigation into bi-directional communication in spectrum sharing-based cognitive radio (Bi-CR) systems. A Bi-CR system can increase the spectral efficiency significantly by sharing the spectrum and through the bi-directional use of spatial resources for two-way communication. On the other hand, the primary user experiences more interference from the secondary users in a Bi-CR system. Satisfying the interference constraint by simply reducing the transmission power results in performance degradation for secondary users. In addition, secondary users also experience self-interference from echo channels due to full duplexing. These imperfections may weaken the potential benefits of the Bi-CR system. Therefore, a new way to overcome these defects in the Bi-CR system is needed. To address this need, this paper proposes some novel power allocation schemes for the Bi-CR system. This contribution is based on two major analytic environments, i.e., noise-limited and interference-limited environments, for providing useful analysis. This paper first proposes an optimal power allocation (OPA) scheme in a noise-limited environment and then analyzes the achievable sum rates. This OPA scheme has an effect in the noise-limited environment. In addition, a power allocation scheme for the Bi-CR system in an interference-limited environment was also investigated. The numerical results showed that the proposed schemes can achieve the full duplexing gain available from the bi-directional use of spatial resources.

A Study on the Problems and Improvement Measures of Licenses for Limited Fishery Business Related to Fisheries Damage due to Public Works Projects (공익사업에 따른 어업피해 관련 한정어업면허에 대한 문제점 및 개선방안에 관한 연구)

  • Seung-Woo Ryu;Eun-Chan Yoon;Kyoung-A Kang
    • The Journal of Fisheries Business Administration
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    • v.55 no.1
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    • pp.21-35
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    • 2024
  • In this study, we collected and analyzed the current status of licenses for the limited fishery business and divided the problems related to licenses for the limited fishery business into partial damage compensation and cancellation compensation areas. In the case of partial damage compensation areas due to existing public water use projects, it is suggested that the issuance of licenses for limited fishery businesses should be reconsidered. In the case of cancellation compensation areas, it is recommended that the disposition of communal fishery businesses that do not require capital investment should be the principle. If capital such as facilities are invested, compensation should be made by Article 52 of the Enforcement Decree of the Land Compensation Act if the licenses for limited fishery business are closed due to other development projects. In addition, we proposed an improvement plan to establish a rational management system for licenses for limited fishery businesses. In addition to these improvement measures, we hope that further investigation and research on licenses for limited fishery business, which have been insufficient so far, will be conducted to promote the comprehensive use of fisheries resources and waters and the sustainable development of fisheries that are the objectives of the Fisheries Act, and contribute to the improvement of the quality of life of the people and the balanced development of the national economy.

Towards true paper-quality displays - The development and commercialisation of $NanoChromics^{TM}$

  • Corr, D;Pichot, F;Leyland, N
    • 한국정보디스플레이학회:학술대회논문집
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    • 2004.08a
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    • pp.37-40
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    • 2004
  • Electrochromic displays offer the possibility of providing high brightness in reflective mode due to the fact that no polarization of the incident or reflected light is required. The use of appropriately roughened reflective layers can enable the diffuse or Lambertian reflection of light. truly imitating the optical nature of paper as a reading medium. Furthermore, the use of an electrochromic system, essentially an electrochemical device, allows for the integration of charge storage layers, endowing such devices with an on-state memory and associated low power consumption. In this paper we describe the $NanoChromics^{TM}$ system and overview the several strategies employed towards the migration of this technology to flexible display formats.

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A New Ship Scheduling Set Packing Model Considering Limited Risk

  • Kim, Si-Hwa;Hwang, Hee-Su
    • Journal of Navigation and Port Research
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    • v.30 no.7
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    • pp.561-566
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    • 2006
  • In this paper, we propose a new ship scheduling set packing model considering limited risk or variance. The set packing model is used in many applications, such as vehicle routing, crew scheduling, ship scheduling, cutting stock and so on. As long as the ship scheduling is concerned, there exits many unknown external factors such as machine breakdown, climate change and transportation cost fluctuation. However, existing ship scheduling models have not considered those factors apparently. We use a quadratic set packing model to limit the variance of expected cost of ship scheduling problems under stochastic spot rates. Set problems are NP-complete, and additional quadratic constraint makes the problems much harder. We implement Kelley's cutting plane method to replace the hard quadratic constraint by many linear constrains and use branch-and-bound algorithm to get the optimal integral solution. Some meaningful computational results and comments are provided.

A NEW LIMITED MEMORY QUASI-NEWTON METHOD FOR UNCONSTRAINED OPTIMIZATION

  • Moghrabi, Issam A.R.
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • v.7 no.1
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    • pp.7-14
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    • 2003
  • The main concern of this paper is to develop a new class of quasi-newton methods. These methods are intended for use whenever memory space is a major concern and, hence, they are usually referred to as limited memory methods. The methods developed in this work are sensitive to the choice of the memory parameter ${\eta}$ that defines the amount of past information stored within the Hessian (or its inverse) approximation, at each iteration. The results of the numerical experiments made, compared to different choices of these parameters, indicate that these methods improve the performance of limited memory quasi-Newton methods.

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A Study on Curricula for Training of Specialist in Textile Design (텍스타일 디자인 전문 인력양성을 위한 교과과정 연구)

  • Lee, Hyun Jin;Choo, Tae Gue;Ku, Yang Suk
    • Fashion & Textile Research Journal
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    • v.15 no.6
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    • pp.899-911
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    • 2013
  • This study investigated the current curricula for the training of textile design specialists. In-depth interviews were conducted with 6 practitioners working in the textile design industry; subsequently, the curricula offered by 20 textile design-related departments at 4-year and 2-year colleges in Korea were used for the data analysis. The results of this study were: First, the problems of textile design education were (1) a limited understanding of commercial designs, (2) an education system concentrated on pattern designs, (3) limited creativity and design expression capacity, (4) limited practical ability and the analysis of collection. Second, most textile design departments at Korean colleges were located in the Seoul/Gyeonggi district and Gyeongbuk/Gyeongnam district. Third, textile material and imagination/expression subjects were a limited part of the curricula; subsequently, a long-term and systematic education system (by college year) was required for the use of basic education subjects. Fourth, there was a shortage of practical subjects in college education despite the perception of commercial designs; in addition, a professional design education (by material and use) were an important part of practical business.