• Title/Summary/Keyword: economic uncertainty

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PREDICTION MODELS FOR SPATIAL DATA ANALYSIS: Application to landslide hazard mapping and mineral exploration

  • Chung, Chang-Jo
    • Proceedings of the KSRS Conference
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    • 2000.04a
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    • pp.9-9
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    • 2000
  • For the planning of future land use for economic activities, an essential component is the identification of the vulnerable areas for natural hazard and environmental impacts from the activities. Also, exploration for mineral and energy resources is carried out by a step by step approach. At each step, a selection of the target area for the next exploration strategy is made based on all the data harnessed from the previous steps. The uncertainty of the selected target area containing undiscovered resources is a critical factor for estimating the exploration risk. We have developed not only spatial prediction models based on adapted artificial intelligence techniques to predict target and vulnerable areas but also validation techniques to estimate the uncertainties associated with the predictions. The prediction models will assist the scientists and decision-makers to make two critical decisions: (i) of the selections of the target or vulnerable areas, and (ii) of estimating the risks associated with the selections.

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A parametric study on seismic fragility analysis of RC buildings

  • Nagashree, B.K.;Ravi, Kumar C.M.;Venkat, Reddy D.
    • Earthquakes and Structures
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    • v.10 no.3
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    • pp.629-643
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    • 2016
  • Among all the natural disasters, earthquakes are the most destructive calamities since they cause a plenty of injuries and economic losses leaving behind a series of signs of panic. The present study highlights the moment-curvature relationships for the structural elements such as beam and column elements and Non-Linear Static Pushover Analysis of RC frame structures since it is a very simplified procedure of non-linear static analysis. The highly popular model namely Mander's model and Kent and Park model are considered and then, seismic risk evaluation of RC building has been conducted using SAP 2000 version 17 treating uncertainty in strength as a parameter. From the obtained capacity and demand curves, the performance level of the structure has been defined. The seismic fragility curves were developed for the variations in the material strength and damage state threshold are calculated. Also the comparison of experimental and analytical results has been conducted.

Equity across Generations and Uncertainty within a Generation: A Welfare Analysis of the National Pension System

  • KWON, KYOOHO
    • KDI Journal of Economic Policy
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    • v.41 no.2
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    • pp.1-39
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    • 2019
  • This paper utilizes a life-cycle overlapping-generations model to quantify the welfare effects of plans to postpone the depletion of the National Pension Fund. In order for the model to incorporate the rapidly changing demographic structure of Korea fully, we build and calibrate a model in transition directly. The model is considered suitable for analyzing the effects of demographic changes on the Korean economy and the effects of plans to change the National Pension System. According to a simulation of the model, to postpone the depletion of the National Pension Fund for 30 years, the premium rate must be increased to 18.3% from the current rate of 9%. By postponing the depletion of the fund reserve, young and future generations gain significantly at the expense of the older generations. The simulation results should be, however, interpreted as meaning that the current system is unjustifiably partial to the older generations. Moreover, given the current premium rate, it is desirable to strengthen the income-redistribution function of the National Pension System.

Supplier Evaluation in Green Supply Chain: An Adaptive Weight D-S Theory Model Based on Fuzzy-Rough-Sets-AHP Method

  • Li, Lianhui;Xu, Guanying;Wang, Hongguang
    • Journal of Information Processing Systems
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    • v.15 no.3
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    • pp.655-669
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    • 2019
  • Supplier evaluation is of great significance in green supply chain management. Influenced by factors such as economic globalization, sustainable development, a holistic index framework is difficult to establish in green supply chain. Furthermore, the initial index values of candidate suppliers are often characterized by uncertainty and incompleteness and the index weight is variable. To solve these problems, an index framework is established after comprehensive consideration of the major factors. Then an adaptive weight D-S theory model is put forward, and a fuzzy-rough-sets-AHP method is proposed to solve the adaptive weight in the index framework. The case study and the comparison with TOPSIS show that the adaptive weight D-S theory model in this paper is feasible and effective.

A Fuzzy Logic Based Software Development Cost Estimation Model with improved Accuracy

  • Shrabani Mallick;Dharmender Singh Kushwaha
    • International Journal of Computer Science & Network Security
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    • v.24 no.6
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    • pp.17-22
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    • 2024
  • Software cost and schedule estimation is usually based on the estimated size of the software. Advanced estimation techniques also make use of the diverse factors viz, nature of the project, staff skills available, time constraints, performance constraints, technology required and so on. Usually, estimation is based on an estimation model prepared with the help of experienced project managers. Estimation of software cost is predominantly a crucial activity as it incurs huge economic and strategic investment. However accurate estimation still remains a challenge as the algorithmic models used for Software Project planning and Estimation doesn't address the true dynamic nature of Software Development. This paper presents an efficient approach using the contemporary Constructive Cost Model (COCOMO) augmented with the desirable feature of fuzzy logic to address the uncertainty and flexibility associated with the cost drivers (Effort Multiplier Factor). The approach has been validated and interpreted by project experts and shows convincing results as compared to simple algorithmic models.

Integrated Broiler Production System - As a Means of Stabilizing Whole Industry with Particular Reference to U.S. Experience - (브로일러계열화 생산조직에 관한 고찰 - 미국의 예를 중심으로 -)

  • 박영인
    • Korean Journal of Poultry Science
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    • v.6 no.2
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    • pp.91-102
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    • 1979
  • The basic problem of the broiler industry is that of fluctuating prices, mainly thanks to unstable supply of and inelastic demand for products as usually indicated as a peculiarity of agricultural commodities. This particularly brings the producer to a great economic risk, because he has to sell products under the condition of pure competition, whereas others from whom he has to buy deal under the condition of oligopoly or even monopoly. Therefore, producers economic position is generally placed in the worst comparing others dealing with, which results in unbalanced economic status of elements involved in broiler operation and further obstruction of industry development as a whole. A certain type of business coordination to overcome such a problem should be measured in order to improve the efficiency of entire operation and thus assure the balanced industry development. The concept of the economic integration developed in modern business system had been adapted to U.S. poultry industry which became common later around the world as a means of stabilizing producers price and whole industry as well. There are two main typos of integration; horizontal and vertical The former refers to the general grouping of similar business units, eg. a hatchery tying with other hatchery, while the latter refers to the knitting together of two or more stages of economic activities, eg. tying together among units of hatching, fled milling, production, processing and marketing. By having the industry integrated, risk and uncertainty involved in various stages of operation could be diversified. The typo of integrating contract between producers and integrators include the share of profits, flat fee payment, feed conversion payment and salary basis. In the U.S., extensive changes in production, processing, and marketing during the last few decades have changed the thicken broiler industry from one of small, widely scattered farms to one that is largo, concentrated and efficient. More than 99 percent of all broilers produced are grown under contract and by integrated firms which vary in size of operation and complexity. About 84 percent of all production is concentrated in 10 States. Some of the other factors ;hat contributed to these choses arc costs, energy use, prices, processing, marketing and demand. No integrated broiler production system has yet been applied in Korea's poultry industry, thus all stages all broiler operation run independently seeking for its own profit. Consequently, producers price fluctuate very widely around the year even more than 50 percent in a few months. This also leads to disadvantages of material supplies, processors and distributors and enforce the industry unstable. The current economic environment in Korea seems that the time for broiler integration comes and as an ideal integrator, feed millers, food processors and producers group may be considered.

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A Theoretical Study on Trust Building in Economic Space (경제공간에서 신뢰형성에 관한 이론적 고찰)

  • Sung, Sin-Je;Lee, Hee-Yul
    • Journal of the Korean Geographical Society
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    • v.42 no.4
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    • pp.560-581
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    • 2007
  • The purpose of this paper is to present a conceptual framework and a stage of development of trust building and to study the factors affecting on the trust building in economics space. Conceptual framework on trust building in economics space is combined of in the three approaches. The macro(structural and institutional) approach includes normative and regulative factors(laws, norms), and positionality in social and economic systems(beliefs, political ideologies, institutions). The meso(intersubjective) approach contains the personal fronts(expressive factors, social cues, significant symbols) and settings(physical space, intermediary such as technologies & knowledges). The micro(subjective) approach comprises the willingness(internalization of value) and calculation(risk and uncertainties analysis) of economic actors. According to sustainable cooperation among economic actors, trust building to the macro(structural and institutional) level, the meso(intersubjective) level, and the micro(subjective) level develop by stages. The factors such as long-term and repeated interaction, information sharing and reciprocity, interdependence and asset specificity, uncertainty, proximity, and culture & norm of corporate and formal institution are determinants on the trust building across economic actors in economic space.

Economic Feasibility Assessment and Analysis of Dual Fuel Systems Utilizing Diesel and Compressed Natural Gas (경유와 압축천연가스의 혼소 시스템에 대한 경제적 타당성 평가 분석)

  • Cho, A-Ra;Lim, Seong-Rin
    • Clean Technology
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    • v.24 no.3
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    • pp.166-174
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    • 2018
  • Since particulate matter has high impacts on human health and everyday life, the dual fuel systems utilizing diesel and compressed natural gas have been developed to improve the environmental performance of diesel vehicles. The objective of this study is to estimate the economic feasibility of the dual fuel system based on real operating data of dual fuel buses and diesel buses. The system is economically feasible if the annual mileage of the dual bus is higher than 30,000 km, or if the unit fuel price of diesel is higher than that of CNG by 408 won. The uncertainty analysis results show that the economic feasibility of the system is probabilistically high, regardless of the variability of input data such as mileage and unit prices for the fuels. The sensitivity analysis results show that diesel and CNG prices are the highest contributor to the net present value of the system. Based on these results, economic incentives are suggested to disseminate the systems. This study would provide valuable economic information for bus business industry and policy maker to help make decisions for applying and disseminating the dual fuel systems to mitigate particulate matter problems.

A Heuristic Algorithm for Designing Traffic Analysis Zone Using Geographic Information System (Vector GIS를 이용한 교통 Zone체계 알고리즘 개발 방안에 관한 연구)

  • Choi, Kee-Choo
    • Journal of Korean Society for Geospatial Information Science
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    • v.3 no.1 s.5
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    • pp.91-104
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    • 1995
  • The spatial aggregation of data, in transportation and other planning processes, is an important theoretical consideration because the results of any analysis are not entirely independent of the delineation of zones. Moreover, using a different spatial aggregation may lead to different, and sometimes contradictory conclusions. Two criteria have been considered as important in designing zone systems. They are scale and aggregation. The scale problem arises because of uncertainty about the number of zones needed for a study and the aggregation problem arises because of uncertainty about how the data are to be aggregated to from a given scale problem. In a transportation study, especially in the design of traffic analysis zone(TAZ), the scale problem is directly related to the number dof zones and the aggregation problem involves spatial clustering, meeting the general requirements of forming the zones system such as equal traffic generation, convexity, and the consistency with the political boundary. In this study, first, the comparative study of delineating spatial units has been given. Second, a FORTRAN-based heuristic algorithm for designing TAZ based on socio-economic data has been developed and applied to the Korean peninsula containing 132 micro parcels. The vector type ARC/INFO GIS topological data mosel has been used to provise the adjacency information between parcels. The results, however, leave some to be desired in order to overcome such problems as non-convexity of the agglomerated TAZ system and/or uneven traffic phenomenon for each TAZ.

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Uncertainties in Risk Assessment

  • Hattis Dale;Froines John
    • 대한예방의학회:학술대회논문집
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    • 1994.02a
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    • pp.440-449
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    • 1994
  • Current risk assessment practices largely reflect the need for a consistent set of relatively rapid, first-cut procedures to assess 'plausible upper limits' of various risks. These practices have important roles to play in 1) screening candidate hazards for initial attention and 2) directing attention to cases where moderate-cost measures to control exposures are likely to be warranted, in the absence of further extensive (and expensive) data gathering and analysis. A problem with the current practices, however, is that they have led assessors to do a generally poor job of analyzing and expressing uncertainties, fostering 'One-Number Disease' (in which everything from one's social policy position on risk acceptance to one's technical judgment on the likelihood of different cancer dose-response relationships is rolled into a single quantity). At least for analyses that involve relatively important decisions for society (both relatively large potential health risks and relatively large potential economic costs or other disruptions), we can and should at least go one further step - and that is to assess and convey both a central tendency estimate of exposure and risk as well as our more conventional 'conservative' upper-confidence-limit values. To accomplish this, more sophisticated efforts are needed to appropriately represent the likely effects of various sources of uncertainty along the casual chain from the release of toxicants to the production of adverse effects. When the effects of individual sources of uncertainty are assessed (and any important interactions included), Monte Carlo simulation procedures can be used to produce an overall analysis of uncertainties and to highlight areas where uncertainties might be appreciably reduced by further study. Beyond the information yielded by such analyses for decision-making in a few important cases, the value of doing several exemplary risk assessments in. this way is that a set of benchmarks can be defined that will help calibrate the assumptions used in the larger number of risk assessments that must be done by 'default' procedures.

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