• Title/Summary/Keyword: stable distribution

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CHARACTERIZATIONS OF SOME POLYNOMIAL VARIANCE FUNCTIONS BY d-PSEUDO-ORTHOGONALITY

  • KOKONENDJI CELESTIN C.
    • Journal of applied mathematics & informatics
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    • v.19 no.1_2
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    • pp.427-438
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    • 2005
  • From a notion of d-pseudo-orthogonality for a sequence of poly-nomials ($d\;\in\;{2,3,\cdots}$), this paper introduces three different characterizations of natural exponential families (NEF's) with polynomial variance functions of exact degree 2d-1. These results provide extended versions of the Meixner (1934), Shanbhag (1972, 1979) and Feinsilver (1986) characterization results of quadratic NEF's based on classical orthogonal polynomials. Some news sets of polynomials with (2d-1)-term recurrence relation are then pointed out and we completely illustrate the cases associated to the families of positive stable distributions.

Design of PID Controller using an Improved Tabu Search (개선된 타부 탐색을 이용한 PID 제어기 설계)

  • 이양우;박경훈;김동욱
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.53 no.5
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    • pp.323-330
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    • 2004
  • In this paper, we propose a design method of PID controller using an improved Tabu Search. Tabu Search is improved by neighbor solution creation using Gaussian random distribution and generalized Hermite Biehler Theorem for stable bounds. The range of admissible proportional gains are determined first in closed form. Next the optimal PID gains are selected by improved Tabu Search. The results of Computer simulations represent that the proposed Tabu Search algorithm shows a fast convergence speed and a good control performance.

A study on the Entry Strategy of Chinese Distribution Market in Korean Company (한국 기업의 중국 유통시장의 진출 전략에 관한 연구)

  • Oh, Soo-Kyun
    • International Commerce and Information Review
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    • v.10 no.4
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    • pp.321-350
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    • 2008
  • The China has opened the distribution market completely since it joined the World Trade Organization on Dec 11 2001. The notable features of Chinese distribution market are the transition from the consumers' monolithic demand to diversification for the luxury goods, well-being products. The regional characteristics of consumers are smart, conservative, optimistic and advanced. and the open door policy has prompted the capitalistic economy gradually. We analyzed the Chinese distribution markets and came up with the following strategies. First, we recommend the setting of the key regional market not covering the whole chinese markets. then we can extend the main market step by step. Second, we need to cooperate and advance with the Korean distribution companies which entered into markets already. Third, we need to acquire the competitive and stable distribution channel in China. Fourth, we need to implement the localization strategy in terms of human resources and procurement. Fifth, the consignment management can be another strategy. I hope this research can be a little help to those who wish to expand to the Chinese markets.

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An Analysis of the Egg Distribution Industry in Korea and Developed Countries in the Post COVID-19

  • Yoon Doo KIM;Sue Ho CHAE
    • Journal of Distribution Science
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    • v.21 no.7
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    • pp.83-90
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    • 2023
  • Purpose: This study aims to set desirable directions for Korea's egg industry by comparing and analyzing the egg distribution structure and policies between Korea and other countries. Research design, data and methodology: We analyzed the current state of egg distribution in Korea, and based on this analysis, we derived problems. In addition, by comprehensively analyzing the egg distribution structure and policy issues in the US, EU, and Japan. Results: As a result of the analysis of the egg distribution status and policy in the country to be analyzed, it was found that for the development of the egg industry in Korea, it is necessary to unify the distribution system for transparent and stable management of the egg distribution process. It was found that detailed and clear information creation and management of egg production and distribution processes were required. Conclusions: We need to establish a regional egg distribution facility base and stipulate that eggs produced in Korea must be compulsorily traded through the regional facility base. Seemingly, scaling-up of the industry is the priority, but the government is promoting various policies to expand small and medium-sized egg joint markets, with limitations in improving the problems of the existing egg distribution structure.

Prediction of negative peak wind pressures on roofs of low-rise building

  • Rao, K. Balaji;Anoop, M.B.;Harikrishna, P.;Rajan, S. Selvi;Iyer, Nagesh R.
    • Wind and Structures
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    • v.19 no.6
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    • pp.623-647
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    • 2014
  • In this paper, a probability distribution which is consistent with the observed phenomenon at the roof corner and, also on other portions of the roof, of a low-rise building is proposed. The model is consistent with the choice of probability density function suggested by the statistical thermodynamics of open systems and turbulence modelling in fluid mechanics. After presenting the justification based on physical phenomenon and based on statistical arguments, the fit of alpha-stable distribution for prediction of extreme negative wind pressure coefficients is explored. The predictions are compared with those actually observed during wind tunnel experiments (using wind tunnel experimental data obtained from the aerodynamic database of Tokyo Polytechnic University), and those predicted by using Gumbel minimum and Hermite polynomial model. The predictions are also compared with those estimated using a recently proposed non-parametric model in regions where stability criterion (in skewness-kurtosis space) is satisfied. From the comparisons, it is noted that the proposed model can be used to estimate the extreme peak negative wind pressure coefficients. The model has an advantage that it is consistent with the physical processes proposed in the literature for explaining large fluctuations at the roof corners.

Trade Structural Analysis of the Steel Distribution Industry between Japan and USA

  • Noh, Hyun-Soo;Kim, Yung-Keun;Lee, Jae-Sung
    • Journal of Distribution Science
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    • v.12 no.11
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    • pp.35-43
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    • 2014
  • Purpose - This study evaluates the mutual influential power regarding the trade volumes of Japan and USA, based on a literature review and an empirical analysis. Through the literature review, I could evaluate each country's actual import-export volume and its status. Further, I could evaluate how each country could influence its trade outcome, through empirical analysis. Research design, data, and methodology - This study aims to review the trade structure to improve Japan-USA economic and social cooperation, as the two countries have reciprocal complementary features, and to examine trade weaknesses and analyze factors influencing trade and its direction, as well as to identify ways to expand trade. Results - The intra-economic potential cooperation fields are numerous. Additionally, anticipated profits from these fields are stable as compared to other fields in the regional economic integration. Conclusion - The interrelations between the two economic identities can provide optimal opportunities for industrial technology cooperation. Under the current aggravated competition in industrial fields, it is advisable to identify ways to secure stable resource suppliers, including the development of export markets.

Design of a control scheme for applying DC power sources to a distribution system (배전시스템에 DC 전력원을 적용하기 위한 제어 기법 설계)

  • Hwang, Chul-Sang;Kim, Gyeong-Hun;Byeon, Gilsung;Jeon, Jin-Hong;Jo, Chang-Hee;Park, Minwon;Yu, In-Keun
    • Proceedings of the KIEE Conference
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    • 2015.07a
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    • pp.1056-1057
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    • 2015
  • A common DC bus is a useful connection for several DC output sources such as photovoltaic (PV), fuel cells, and batteries. Operation of the common DC power system with more than two DC output sources, especially in a stand-alone mode, requires a control scheme for the stable operation of the system. In this paper, a control scheme has been developed for applying DC power sources to the distribution system. The purpose of the control scheme is to make the best use of the DC power sources. The DC power system consists of PV, two energy storage systems and a DC-AC inverter with the control scheme. A distribution system was modeled in PSCAD/EMTDC. As the results, the control scheme is applied to the DC-AC inverter and the DC-DC converter for transfer operations between the grid-connected and the stand-alone mode to keep the DC bus and the AC voltage constant. The results from the simulation demonstrate the stable operation of a grid connected DC power system.

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A Study on the Development Strategies and Measuring Consumer′s Willingness to Pay for the Quality-Certificated Environmental-Friend Products - Focused on Rice, Lettuce, and Bean Curd at Cheonan-city (품질인증 친환경농산물의 소비자가치 추정 및 유통정책 방향에 관한 연구 - 천안지역의 쌀, 상추, 두부를 중심으로 -)

  • Jung, Chan-Wung;Heo, Seung-Wook;Kim, Ho
    • Korean Journal of Organic Agriculture
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    • v.11 no.2
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    • pp.23-42
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    • 2003
  • The study must have standpoints for the stable market construction of the Environmental-Friendly agricultural products of the quality-certificated which has rapidly grown due to a discussion of the environment and agriculture, income increase and the interests on foods stability. The survey was conducted through face-to-face interview of 200 adults who are in their twenties or more in Cheonan-city. In this research, the Environmental-Friendly agriculture was a clean agriculture not using a fertilizer or chemicals and the agriculture which protects the environment by preventing the environmental pollution. In the analyses of the consumer's willingness to pay, the rice showed 69,851 won, and a lettuce and bean-curd showed 947 won and 1.412 won respectively. In terms of current issues of the policy, to establish the stable circulation structure and consumption strategy, there must be a clearness raise of the Quality Authentication (QA) Mark. To raise the trust through quality authentication, there must be transparency raise of information by distribution stages and the thorough post management of the official institutes. Also, to persue the competitive product differentiation, there must be the settlement of the product brand on the market, development of the new production technology and a classification of consumers by incomes. Finally to construct stable distribution and price system, there must be active participation of the local agricultural cooperatives in the distribution of the Environmental-Friendly agricultural products of the quality-certificated and the understanding of the proper price of the consumer market and flexible strategy of the price change.

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Assay of Heat Stable Enterotoxin Producing E. coli (내열성장독소 생산 대장균의 판정)

  • Chang, Woo-Hyun;Kim, Moon-Gyo;Choi, Myung-Sik;Yang, Nam-Ung;Ko, Kwang-Wook;Seo, Jung-Ki
    • The Journal of the Korean Society for Microbiology
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    • v.18 no.1
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    • pp.53-58
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    • 1983
  • Enterotoxigenic E. coli is one of causative agents of the infantile diarrhea and traveler's diarrhea. A modified infant mouse assay(IMA) was developed for the detection of heat stable enterotoxin (ST) of E. coli isolated from diarrheal and control infants and assay system was established with using enterotoxin producing reference strains. The supernatant of the 24 hour-shaking culture of E. coli in Casamino Acid Yeast Extract Salt Broth(CYES-2) was ingested orally into the 2-4 day old ICR mice. After the mice were kept at $25^{\circ}C$ for 4 hours, they were sacrificed and the gut weight body weight ratio(GW/BW) was taken as the index of fluid accumulation induced by heat stable enterotoxin of E. coli. The results obtained were as follows; 1. The GW/BW responses of IMA tested with enterotoxin reference strains of E. coli(E. coli O148H28:$ST^+LT^+$, E. coli $O78H^-:ST^+LT^+$, E. coli O15H11:$ST^-LT^+$, E. coli O1H7:$ST^-LT^-$) appeared ta be ST dose-dependent, and not LT-dependent. From the dose-response curve, $25{\mu}l$ of culture supernatant was determined as test amount of the IMA. 2. Frequency distribution of IMA result from 643 strain of E. coli showed normal distribution at low GW/BW ratio and dispersed pattern at high GW/BW ratio. The GW/BW ratios of $0.056{\pm}0.004(mean{\pm}SD)$ of normal distribution which distributed from 0.044 to 0.068(P<0.01) was considered as ST negative. Thus the GW/BW ratio above 0.069 could be regarded as ST positive.

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A STUDY ON THE THREE DIMENSIONAL FINITE ELEMENT ANALYSIS OF THE STRESSES ACCORDING TO THE CURVATURE OF ARCH AND PLACEMENT OF IMPLANTS (악궁의 만곡도 및 임플랜트 위치에 따른 삼차원적 유한요소 응력분석)

  • Lee, Don-Oh;Chung, Chae-Heon;Cho, Kyu-Zong
    • The Journal of Korean Academy of Prosthodontics
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    • v.33 no.1
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    • pp.98-129
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    • 1995
  • The purpose of this study was to evaluate how mandibular implant-supported fixed complete prosthesis, implant and mandible responded mechanically, according to curvature of arch, number and location of fixture, and amounts of load. The shape of mandibular arch was tapered or square form and, 4 or 6 fixtures were implanted in each arch model. A vertical load of 10kg was applied at the center of prosthesis and a vertical load of 20kg was applied at the location of the 10mm or 20mm cantilever posterior to the most distal implant. Three-dimensional finite element analysis was performed for stress distribution and deflection using commercial software(ABAQUS program) for Sun-SPARC Workstation. The results were as follows : 1. The case square arch form was more stable to compare with that of tapered arch form in respect of stress distribution and displacement under vertical load on the center of prosthesis. 2. 6-implants cases were more stable than 4-implants cases for decreasing bending torque under vertical load on the center of prosthesis. 3. Under vertical load on cantilever extension, the case of 10mm long cantilever was more stable than that of 20mm long cantilever in respect of stress distribution and displacement. 4. Under vertical load on cantilever extension, 6-implants cases had a tendency to reduce displacement and to increase the reaction force of supporting point due to increasing of the bending stiffness of the prosthesis than 4-implant case. 5. When the ends of 10mm or 20mm long cantilever were loaded, the most distal implant was under compressive stress but the second most distal implant was under the highest tensile stress and the remaining implants were under varying tensile stress. 6. Because 6-implants cases had smaller displacement than 4-implants cases, 6-implants cases were more favorable in respect of prevention of screw loosening under repeated loadings.

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