• Title/Summary/Keyword: 역진성

Search Result 48, Processing Time 0.023 seconds

Adaptive Fuzzy Sliding Mode Control for Nonlinear Systems without Parameter Projection Method (파라미터 투영 기법이 필요 없는 비선형 시스템의 적응 퍼지 슬라이딩 모드 제어)

  • Seo, Sam-Jun
    • Journal of the Korean Institute of Intelligent Systems
    • /
    • v.21 no.4
    • /
    • pp.499-505
    • /
    • 2011
  • In this paper, we proposed an adaptive fuzzy sliding mode control for nonlinear systems without parameter projection method. By modifying the controller structure, the parameters of the estimated input gain function are guaranteed not being identically zero and it is shown that the control scheme will not cause any implementation problem even if the estimated value of input gain function is zero at any moment during on-line operations. Except for the input gain function which an approximate estimate for its lower bound is needed, the proposed control scheme does not assume a priori the exact values of the bounding parameters. Based on Lyapunov synthesis methods, the overall control system guarantees that the tracking error asymptotically converges to zero and that all signals involved in controller are uniformly bounded. This can be illustrated by the simulation results for an inverted pendulum system.

Performance Evaluation of Wireless Networked Control System Based on IEEE 802.15.4e With Redundancy (중복 전송을 고려한 IEEE 802.15.4e기반 무선 네트워크 제어 시스템 성능 평가)

  • Yen, Bui Xuan;Lee, Wonhee;Kim, Youngsuk;Yoo, Myungsik
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.38B no.7
    • /
    • pp.572-580
    • /
    • 2013
  • IEEE 802.15.4e is a prospective standard for low latency control application in industries. This paper proposes a framework to evaluate the closed loop IEEE 802.15.4e based WNCS performance. The framework consists of two models: closed loop control system model and network model. The network model focuses on the PHY parameters of wireless link and takes the channel parameters into consideration. The PHY model combining with MAC model gives the control system model the probability of packet loss in a super-frame. In addition, redundancy mechanism is considered in IEEE 802.15.4e to reduce to data frame loss probability. The simulation is implemented in Matlab, PHY model takes the channel parameters from empirical results. Hence our evaluation gives insight into behavior of WNCS in different environments and it provides us a tool to design wireless network to achieve a good performance for control system.

Design of a Neuro-Fuzzy System Using Union-Based Rule Antecedent (합 기반의 전건부를 가지는 뉴로-퍼지 시스템 설계)

  • Chang-Wook Han;Don-Kyu Lee
    • The Transactions of the Korea Information Processing Society
    • /
    • v.13 no.2
    • /
    • pp.13-17
    • /
    • 2024
  • In this paper, union-based rule antecedent neuro-fuzzy controller, which can guarantee a parsimonious knowledge base with reduced number of rules, is proposed. The proposed neuro-fuzzy controller allows union operation of input fuzzy sets in the antecedents to cover bigger input domain compared with the complete structure rule which consists of AND combination of all input variables in its premise. To construct the proposed neuro-fuzzy controller, we consider the multiple-term unified logic processor (MULP) which consists of OR and AND fuzzy neurons. The fuzzy neurons exhibit learning abilities as they come with a collection of adjustable connection weights. In the development stage, the genetic algorithm (GA) constructs a Boolean skeleton of the proposed neuro-fuzzy controller, while the stochastic reinforcement learning refines the binary connections of the GA-optimized controller for further improvement of the performance index. An inverted pendulum system is considered to verify the effectiveness of the proposed method by simulation and experiment.

A Study on the Taxation Equity between Non-Residential Real Estate and Apartment Houses (비주거용 부동산과 아파트의 과세형평성에 관한 연구)

  • Im, Dong Heok;Choi, Min Seub
    • Korea Real Estate Review
    • /
    • v.27 no.3
    • /
    • pp.87-102
    • /
    • 2017
  • The purpose of this study was to compare the taxation equity of non-residential collective real estate based on its standard market prices set by National Tax Service and those for taxation set by the Ministry of Government Administration and Home Affairs with that of the apartment houses in Seoul, South Korea. The study findings were as follows. First, the analysis results of the standard market price rates of non-residential collective real estate pointed to a huge gap in the assessment rate (AR) of the taxation standards among the Gu offices. Second, there was a big coefficient of dispersion (COD) in the standard market prices of non-residential collective real estate, which confirmed the presence of horizontal inequity. Finally, there was regressive vertical inequity, which leads to the undervaluation of high-value assets, in the standard market prices of non-residential collective real estate. The evaluation of the standard market prices of non-residential collective real state should thus reflect the market prices and the addition and assessment of the land and buildings to achieve taxation equity. Based on these findings, it is hoped that this study will make a significant contribution to the improvement of the official announcement system for non-residential real estate based on real transactions during the shift to such system.

An Analysis of the Optimal Integration of Korea's Public Pension Schemes (공적연금(公的年金)의 적정급여구조(適正給與構造)에 관한 연구(硏究))

  • Yoo, Il-ho
    • KDI Journal of Economic Policy
    • /
    • v.12 no.4
    • /
    • pp.113-126
    • /
    • 1990
  • With the introduction of the national pension, efficient integration of Korea's four public pension schemes has been discussed. The main point of such discussions is whether to have a progressive scheme or an income-proportional one. Under the assumption of a perfect labor market, it has been proved in the income tax literature that the regressive tax scheme with the 0 % tax rate to the most able person (person earning highest income) is pareto efficient, if there is an incentive problem in the labor supply. In this paper, a life-cycle model with a linear benefit schedule, when there is uncertainty about future earning ability, is studied. It is proved that the second best pension scheme is that having a progressive benefit schedule. This result implies that integration into a progressive pension scheme, like the current national pension, is required not only for efficiency but also for equity.

  • PDF

An Examination of Financial Feasibility and Redistributive Effect of Universal Basic Income (기본소득의 재정적 실현가능성과 재분배효과에 대한 고찰)

  • You, Jong-sung
    • 한국사회정책
    • /
    • v.25 no.3
    • /
    • pp.3-35
    • /
    • 2018
  • This article critically reviews the arguments that deny the financial feasbility and effectiveness of universal basic income as an alternative to existing social security systems and makes some suggestions to design effective and efficient basic income schemes. Regarding the financial feasibility of universal basic income, I argue that replacement of the existing regressive tax expenditures with universal basic income without raising tax rates can effectively reduce tax burden or provide income support to a majority of people except the rich. Addition of basic income to the tax base and reduction of the number of beneficiaries of public assistance and the amount of cash payment for them can further help save money. Regarding the redistributive effect, I note that the targeting ability of the existing social security systems is not good and that "the paradox of redistribution" that universal-type programs tend to be more redistributive than selective programs applies to universal basic income as well. I demonstrate significant redistributive effect of a hypothetical revenue-neutral basic income scheme and reviews several empirical studies done in Korea and abroad to show that basic income can be more effective in redistribution than social insurances or public assistance programs. Lastly, I emphasize the need to construct a reliable tax-benefit microsimulation model to help researchers to study redistributive effects of basic income schemes and other taxes and social policies.

The Growth of the Korean Welfare State and its implications for redistribution: Who has been excluded? (한국 복지국가 성장의 재분배적 함의: 누가 복지국가로부터 소외됐는가?)

  • Nahm, Jaewook
    • 한국사회정책
    • /
    • v.25 no.4
    • /
    • pp.3-38
    • /
    • 2018
  • This study aims to analyse the redistributive impact of the welfare state growth in Korea after 2000s and establish whether there are people excluded from the benefits of the growth. The growth of the Korean welfare state has been achieved by universalizing welfare benefits under the social insurance-centered institutions which are the legacies of the productivist/developmental welfare regime. When it comes to redistribution impacts, the welfare state growth improved inequality among old age populations to a certain degree due to the introduction of the Basic Pension. On the other hand, welfare benefits for the working poor population has hardly been improved in spite of the growing welfare state. It can be said, therefore, that low-income working-age populations have been excluded from the growth of Korean welfare state. These groups are mostly in middle-old age, unemployed or precariously employed and half of them were female householders. The exclusion of these groups from the Korean welfare state shows that the growth of the Korean welfare state was unbalanced. To include the excluded into the Korean welfare state, it is necessary to increase non-insurance social provisions, extend the range of application of the social insurances, integrate income protection, employment service, and vocational training for the working poor, and combine universal and targeted welfare benefits.

The Economic Effects of Tax Incentives for Housing Owners: An Overview and Policy Implications (주택소유자(住宅所有者)에 대한 조세감면(租稅減免)의 경제적(經濟的) 효과(效果) : 기존연구(旣存硏究)의 개관(槪觀) 및 정책시사점(政策示唆點))

  • Kim, Myong-sook
    • KDI Journal of Economic Policy
    • /
    • v.12 no.2
    • /
    • pp.135-149
    • /
    • 1990
  • Housing owners in Korea have a variety of tax advantages such as income tax exemption for the imputed rent of owner-occupied housing, exemption from the capital gains tax and deduction of the estate tax for one-house households. These tax reliefs for housing owners not only conflict with the principle of horizontal and vertical equity, but also lead to resource misallocation by distorting the housing market, and thus bring about regressive distribution effects. Particularly in the case of Korea with its imperfect capital market, these measures exacerbate the inter-class inequality of housing ownership as well as inequalities in wealth, by causing the affluent to demand needlessly large housing, while the poor and young experience difficulties in purchasing residential properties. Therefore, the Korean tax system must be altered as follows in order to disadvantage owner-occupiers, especially those owners of luxury housing. These alterations will promote housing-ownership, tax burden equity, efficiency of resource allocation, as well as the desirable distribution of income. First, income tax deductions for the rent payments of tenants are recommended. Ideally, the way of recovering the fiscal equivalence between the owner-occupiers and tenants is to levy an income tax on the former's imputed rents, and if necessary to give them tax credits. This, however, would be very difficult from a practical viewpoint, because the general public may perceive the concept of "imputed rent" as cumbersome. Computing the imputed rent also entails administrative costs, rendering quite reasonable, the continued exemption of imputed rent from taxation with the simultaneous deduction in the income tax for tenants. This would further enhance the administrative efficiency of income tax collection by easing assessment of the landlord's income. Second, a capital gains tax should be levied on the one-house household, except with the postponement of payments in the case that the seller purchases higher priced property. Exemption of the capital gains tax for the one-house household favors those who have more expensive housing, providing an incentive to the rich to hold even larger residences, and to the constructors to build more luxurious housing to meet the demand. So it is not desirable to sustain the current one-house household exemption while merely supplementing it with fastidious measures. Rather, the rule must be abolished completely with the concurrent reform of the deduction system and lowering of the tax rate, measures which the author believes will help optimize the capital gains tax incidence. Finally, discontinuation of the housing exemption for the heir is suggested. Consequent increases in the tax burden of the middle class could be mitigated by a reduction in the rate. This applies to the following specific exemptions as well, namely, for farm lands, meadows, woods, business fields-to foster horizontal equity, while denying speculation on land that leads to a loss in allocative efficiency. Moreover, imperfections in the Korean capital market have disallowed the provision of long term credit for housing seekers. Remedying these problems is essential to the promotion of greater housing ownership by the low and middle income classes. It is also certain that a government subsidy be focused on the poorest of the poor who cannot afford even to think of owning a housing.

  • PDF