• Title/Summary/Keyword: shrinking

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Synthesis of 90/102(170)/150 linear CA using 90/150 linear CA (90/150 선형 CA를 이용한 90/102(170)/150 선형 CA 합성)

  • Choi, Un-Sook;Cho, Sung-Jin;Kim, Han-Doo;Kwon, Min-Jeong;Kim, Seok-Tae
    • The Journal of the Korea institute of electronic communication sciences
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    • v.11 no.9
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    • pp.885-892
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    • 2016
  • The nonlinear sequence generator called the shrinking generator was designed as nonlinear keystream generator composed by two maximum-length LFSRs. The shrunken sequences generated by the shrinking generator are included in the class of interleaved sequences and can be modelled as one of the output sequences of cellular automata (CA). In this paper, we propose a method for synthesizing a 90/150 CA-based sequence generator to generate a family of sequences with the same characteristic polynomial as the shrunken sequences.

Locational Characteristics and Shrinking Prediction of Rice Paddy Fields in South Korea (우리나라 논의 지리적 입지특성과 축소지역 예측)

  • Kim, Hyun-Joong;Chung, IL-Hoon
    • Journal of Agricultural Extension & Community Development
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    • v.27 no.2
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    • pp.75-87
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    • 2020
  • The purpose of this study is to investigate the location characteristics of the rice paddy fields and to predict shrinking areas of them. The study area is in South Korea nationwide, and a 300×300m raster level is adopted as a spatial analysis unit. The binary logit model and spatial simulation model are employed for the analyses. As a result, population, industry, climate and nature, and accessibility play a significant role in determining rice paddy fields' locations. It is predicted that the shrinking rate will be high in Gangwon-do, Gyeongsangbuk-do, and Gyeongsangnam-do until 2027. The hot spots are intensively shaped in the inland of Gangwon-do, eastern parts of Gyeonggi-do, and the borders of Gyeongsangnam-do and Jeollabuk-do between Charyeong and Sobaek mountain ranges. Using Gimcheon-si as an example, the study suggests fundamental policy implications for taking advantage of the simulation results from the lens of local agriculture. Several policy measures are proposed for improving management strategies for the rice paddy fields in the long run.

Study on the Spinning Processes Combined with Shear and Shrinking Deformation (전단 및 교축변형이 조합된 복합스피닝 공정에 관한 연구)

  • 이항수;강정식
    • Transactions of Materials Processing
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    • v.8 no.5
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    • pp.507-519
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    • 1999
  • An approach using the energy method has veen proposed for the analysis of cone spinning having the complicated deformation modes mixed by shear and normal deformation. In the proposed method, the corresponding solution is found through optimization of the total energy dissipation with respect to the parameters assumed by the velocity field defined as the variation of the length in longitudinal direction. The sheet blank is divided into three layers to consider the bending effect and the energy dissipated by shear deformation is superposed to the energy consumption due to normal deformation related with the shrinking deformation is superposed to the energy consumption due to normal deformation related with the shrinking deformation of axi-symmetric sheet element for the evaluation of total deformation energy. In order to check the validity of the proposed method, the complex spinning for making the conical cup is analyzed and the computed results are compared with the experimental results. In comparison of the computed results with existing experimental results,, the good agreement is obtained for the variation of outer radius and the distribution of thickness, and it has thus been shown that the present approach is applicable to the analysis of complex spinning.

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Simulative Calculations of Food Waste Reduction Using Kineto-transport Models (동력학-전달 모델을 활용한 식품 폐기물 감량 해석)

  • Cho, Sun-joo;Kim, Tae-wook;Kwon, Sung-hyun;Cho, Daechul
    • Journal of Environmental Science International
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    • v.30 no.6
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    • pp.429-439
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    • 2021
  • Food waste is both an industrial and residential source of pollution, and there has been a great need for food waste reduction. As a preliminary step in this study, waste reduction is quantitatively modeled. This study presents two models based on kinetics: a simple kinetic model and a mass transport-shrinking model. In the simple kinetic model, the smaller is the reaction rate constant ratio k1, the lower the rate of conversion from the raw material to intermediate products. Accordingly, the total elapsed reaction time becomes shorter. In the mass transport-shrinking model, the smaller is the microbial decomposition resistance versus the liquid mass transfer resistance, the greater is the reduction rate of the radius of spherical waste particles. Results showed that the computed reduction of waste mass in the second model agreed reasonably with that obtained from a few experimantal trials of biodegradation, in which the microbial effect appeared to dominate. All calculations were performed using MATLAB 2020 on PC.

A Diagnosis of Shrinking City Using Population Gradient Curve: A Case Study on the City of Yeong-ju (인구밀도경사함수를 이용한 도시축소현상 진단 - 영주시를 사례로 -)

  • Kim, Min-Seok;Byun, Tae-Geun;Lee, Sang-Ho
    • Journal of the Korean Regional Science Association
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    • v.35 no.4
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    • pp.33-45
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    • 2019
  • Due to the global low growth trend, urban shrinkage is a major issue of urban policy in major industrialized countries. According to the research results of the KRIHS(Korea Research Institute for Human Settlements, 2016), 23 out of 77 cities in Korea were diagnosed as continuous or temporary shrinking cities. However, the criterion for diagnosing shrinking cities remain on the simple demographic side, and the spatial shrinkage pattern of the city is not considered. Therefore, this study diagnosed urban shrinkage phenomenon considering the characteristics of Yeong-ju, a poly-centric city, by using the population gradient curve, which is one of the urban spatial structure analysis methods. As a result of the diagnosis, Yeong-ju turned out to be a shrinking city with the population density and the slope of population density increasing. In the case of area of Dong, a sprawl phenomenon in which the population density of the CBD and the slope of the population density were decreased was shown. And in the case of Punggi-eup, a simple shrinkage phenomenon in which only the population density of the CBD was decreased was shown. The results show that even within a city, the pattern of spatial change can be different for each centers. In the case of a city with a poly-centric structure, the implications for the individual diagnosis of not only the entire city but also the detailed area were drawn.

Influence of ACLSV-infection on Fruit Quality of 'Hongro' Apples (ACLSV(Apple chlorotic leafspot virus) 감염이 사과 '홍로' 품종의 과실품질에 미치는 영향)

  • Kim, Hyun-Ran;Kim, Jeong-Soo;Hwang, Jeong-Hwan;Lee, Sin-Ho;Choi, Gug-Seon;Choi, Yong-Mun
    • Research in Plant Disease
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    • v.10 no.2
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    • pp.145-149
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    • 2004
  • 'Hongro' is one of the most important apple cultivars whose growing area is increasing because of its good quality. Recently fruit shrinking symptom causing decrease of fruit size, juice, and quality, appears in some commercial 'Hongro' orchards. The average frequency of occurrence of fruit shrinking symptom was 12 % of total trees investigated and Apple chlorotic leaf spot virus (ACLSV) was detected from all the trees showing fruit shrinking symptom by ELISA. A typical virus infection symptom of leaf epinasty and stem necrosis appeared on woody indicators, Spy227 and Virginia crab grafted with infected trees and all the grafted trees showed positive reaction to ACLSV antiserum by ELISA. It was proved that ACLSV can be easily transmitted by grafting. ACLSV was also isolated from the leaves of C. quinoa inoculated with sprouting leaf sap of infected trees. To prove that the fruit shrinking symptom was caused by ACLSV infection, ACLSV-infected scion was grafted on virus-free 'Hongro/M9' and the fruit characteristics were investigated. Consequently the same symptoms of fruit size and juice decreasing were observed from the trees grafted with ACLSV-infected scion. Therefore, it is suggested that the fruit shrinking symptom is caused by ACLSV infection and 'Hongro' can be classified as sensitive cultivar to ACLSV.

Effects of High-Speed Train on Regional Population In-Migration - Focusing on Shrinking City and Demographic Structure - (고속철도가 지역 인구 이동에 미치는 영향 -지방소멸 위험과 인구 구조를 중심으로-)

  • Eunji Kim;Heeyeun Yoon
    • Journal of the Korean Regional Science Association
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    • v.40 no.2
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    • pp.91-106
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    • 2024
  • Around the world, many countries experiencing the issue of shrinking cities are continually expanding high-speed rail networks to enhance regional accessibility and address imbalances. This study analyzed the effects of high-speed train operations on the age-specific population migration in South Korean municipalities from 2012 to 2019, taking into account the risk levels of shrinking cities. For this purpose, an analysis was conducted using age-specific net in-migration population as the dependent variable, employing the spatial panel autoregressive model. The research results indicated that the influence of high-speed rail on regional population inflow varies depending on the risk level of shrinking city. In other words, high-speed railway operations had positive effects on population inflow in the capital areas and some major cities, while explained population outflow in the other regions. High-speed railways particularly exerted a significant impact on the inflow of the young and middle-aged population, representing the working age, but this effect was also limited to regions with a low risk of shrinkage. The findings of this study emphasize the importance of considering planned population and industrial attraction when installing high-speed rail with the goal of achieving regional balanced development and mitigating shrinkage. The results of this study also suggest the need for subsequent research to explore factors that positively influence population structure and inflow based on the level of shrinkage risk in each region, as well as the introduction of new policies tailored to the specific situations of each local government.

Hydrated Lime Roasting of Precious Metal Ores with A Cyclone Reactor

  • Cho, Chong S.
    • Proceedings of the Korea Association of Crystal Growth Conference
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    • 1997.06a
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    • pp.53-60
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    • 1997
  • The roasting of pyrite with a cyclone reactor have been studied in terms of investigating the reaction behavior of pyrite. The development of a fundamental model for pyrite oxidation and lime sulfation in a vertical cyclone reactor. The model assumes a chemical control shrinking core behavior for the pyrite and a fluid film control shrinking core behavior for the lime. The oxygen and sulphur dioxide concentrations and the energy balance for the gas, pyrite and lime particles are solved. The model was solved and characterized numerically. Experiments have been performed to study the influence of reaction parameters such as reactor temperatures, pyrite particle sizes, air flow rates, feeding rates, and mixing ratio of pyrite and lime. The oxidation and sulfation products were characterized chemically and physically.

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A New Class of Self-Shrinking Generators (새로운 자기 수축 발생기)

  • 최세아;양경철
    • Proceedings of the Korea Institutes of Information Security and Cryptology Conference
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    • 2002.11a
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    • pp.88-91
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    • 2002
  • 자기 수축 발생기(self-shrinking generator)는 Meier와 Staffelbach에 의해 제안되었으며[4], 구조가 간단하고 키수열을 생성하는 속도가 빠르기 때문에 스트림 암호시스템으로 각광받고 있다 [5]. 본 논문에서는 자기 수축 발생기의 새로운 구성방법을 제안한다. 제안된 자기 수축 발생기는 하나의 선형귀환회로와 주어진 짝수 m에 의하여 정의되며 일반적으로 선형귀환회로의 귀환다항식으로 원시다항식을 사용한다. 이 경우 키수열은 균형성을 만족하며, 선형귀환회로의 귀환다항식의 차수를 $d_{Y}$ 라고 하면 주기는 $d_{Y-2}$ 이다. m을 $2^{η}$ζ로 표현하면 선형복잡도 Lz는 $d_{Y}$ +η-3/$\leq$ $L_{Z}$ $\leq$m/2($d_{Y}$ -1 - ($d_{Y}$ -2))이다. 따라서 제안된 자기 수축 발생기는 기존의 자기 수축 발생기에 비하여 암호학적으로 우수한 성질을 갖는다.다.

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