• Proceedings of the KSME Conference
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• 2000.04a
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• pp.725-730
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• 2000

Genetic algorithms based on the theory of natural selection, have been applied to many different fields, and have proven to be relatively robust means to search for global optimum and handle discontinuous or even discrete data. Genetic algorithms are widely used for unconstrained optimization problems. However, their application to constrained optimization problems remains unsettled. The most prevalent technique for coping with infeasible solutions is to penalize a population member for constraint violation. But, the weighting of a penalty for a particular problem constraint is usually determined in the heuristic way. Therefore this paper proposes, the effective technique for handling constraints, the ranking penalty method and hybrid genetic algorithms. And this paper proposes dynamic mutation tate to maintain the diversity in population. The effectiveness of the proposed algorithm is tested on several test problems and results are discussed.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2000.05a
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• pp.134-137
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• 2000

Genetic algorithms(GAs) have been widely used as a method to solve optimization problems. This is because GAs have simple and elegant tools with reproduction, crossover, and mutation to rapidly discover good solutions for difficult high-dimensional problems. They, however, do not guarantee the convergence of global optima in GA-hard problems such as deceptive problems. Therefore we proposed a Schema Co-Evolutionary Algorithm(SCEA) and derived extended schema 76988theorem from it. Using co-evolution between the first population made up of the candidates of solution and the second population consisting of a set of schemata, the SCEA works better and converges on global optima more rapidly than GAs. In this paper, we show advantages and efficiency of the SCEA by applying it to some problems.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.101.4-101
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• 2001

Evolutionary algorithm has been receiving a remarkable attention due to the model-free and population-based parallel search attributes and much successful results are coming out. However, there are some problems in most of the evolutionary algorithms. The critical one is that it takes much time or large generations to search the global optimum in case of the objective function with multimodality. Another problem is that it usually cannot search all the local optima because it pays great attention to the search of the global optimum. In addition, if the objective function has several global optima, it may be very difficult to search all the global optima due to the global characteristics of the selection methods. To cope with these problems, at first we propose a preprocessing process, grid-filtering algorithm(GFA), and propose a new distributed evolutionary ...

• Journal of Plant Biotechnology
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• v.43 no.2
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• pp.147-150
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• 2016

Global GM crops continue to grow. They have reached 181 million hectares. A total of 28 countries have approved biotech crops for planting. More than 60 countries have approved biotech crops to be imported as food and feed since 1996, meaning that biotech crops are now commonly accepted in those countries. Although biotech crops provide key solutions for the challenge of global food security in the future due to population growth and climate change, there are still some debates on whether biotech crops should be accepted in many countries including Korea. Therefore, it is very important to make people understand that GM crops will provide benefits to both farmers and consumers. In this review, current global status of GM crop development and commercialization are summarized.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.11a
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• pp.512-513
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• 2003

Human activities have become a major factor that significantly changes the global environment. Mankind has increasingly used land, water, minerals and other natural resources since the beginning of industrialization, and future growth in the population and economy is thought to further enhance the impact upon the Earth. The global climate, biogeochemical process and natural ecosystems are closely linked with one another, and changes in any one of these systems may effect the others, which could result in consequences detrimental to humans and other living organisms on the Earth.(omitted)

• Journal of the Korean Professional Engineers Association
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• v.45 no.5
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• pp.26-35
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• 2012

Korea is now the 12th largest economy in the world, surpassing its annual trade in the amount of $1 trillion, and it has joined the socalled 20-50 Club, becoming one of the seven countries in the world with capita income of more than $20,000 with population of 50 million. However it ranked 24th of the Global competitiveness index evaluated by World Economic Forum based on the basic requirements including infrastructures, efficiency enhances, innovation and sophistication factors, etc. The extensive and efficient SOC infrastructures are critical for ensuring the global competitiveness of each country. Effective modes of SOC facilities including quality roads, railroads, ports, air transport, etc will be able to reduce the annual traffic congestion cost as well as macro economic logistics costs in Korea, thereby the global competitiveness can be strengthened in the global market.

• Food Science and Industry
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• v.50 no.4
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• pp.2-11
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• 2017

The external factors of global flavor market include the world economy, population growth, urbanization, consumer spending, raw material availability, pricing, and regulatory issues. And the internal factors as product pricing and technology development may lie the flavor house's competitiveness and cost considerations. In developing countries, rising preference for packaged food and beverages and increasing personal expenditures will drive demand for flavor market. Increasing consumer demand for natural products, driven in part by health concerns and a desire for transparency in labeling will impact the demand. The increasing demand for salt and sugar reduction will boost demand for flavors to maintain the overall taste. The use of quality and innovative flavors in the beverages and the multifunctional flavors has a positive influence on the global market. The global flavor industry has the presence of several drivers and positive trends, with its future expected to be promising.

• Atmosphere
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• v.17 no.2
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• pp.185-193
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• 2007

This study investigates urbanization effect in warming trend of surface air temperature over Korea. The data used in this study consist of the daily minimum and maximum temperatures during the period of 32 years(1968-1999) from 16 stations of KMA. To calculate magnitude and trend of urbanization effect, stations were classified into urban and rural stations using population statistics. Urban stations were defined as those with population densities greater than 1000 persons per kilometer squared in 1995. The others were defined as rural stations. The urban stations were also subdivided into two groups according to their population totals. For estimates of urban effect magnitude, temperature change was calculated by comparing 16-year mean values between 1968-83 and 1984-99. Then, the difference between each urban station and every rural station was calculated. During the analysis period of 32 years, maximum temperature increase is $1.22^{\circ}C$. In the total temperature increase, urban effect is estimated by 28.7%. For minimum temperature, it becomes larger by about 10% than that in maximum temperature. Therefore, urban effect in an increasing trend of minimum temperature is 38.9% in the change of $1.13^{\circ}C$.

• Korean System Dynamics Review
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• v.10 no.3
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• pp.105-124
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• 2009

The situation of the global food markets has been being rapidly restructured and entering on a new phase by new dynamic and driving forces. The factors such as economic growth and income increase, high energy price, globalization, urbanization, and global climate change are transforming patterns of food consumption, production, and markets. The prices and markets of world food and energy are getting increasingly linked each other. Food and fuel are the global dilemma issues associated with the risk of diverting farmland or of consuming cereals for biofuel production in detriment of the cereals supply to the global food markets. An estimated 100 million tons of grain per year are being redirected from food to fuel. Therefore, the objectives of this study are as follows: Firstly, the study examines situations of the world food and energy resources, analyzes the trends of prices of the crude oil and biofuel, and formulates the food-energy links mechanism. Secondly, the study builds a simulation model, based on system dynamics approach, for not only analyzing the global cereals market and energy market but also forecasting the global production, consumption, and stock of those markets by 2030 in the future. The model of this study consists of four sectors, i.e., world population dynamics sector, global food market dynamics sector, global energy market dynamics sector, scenario sector of world economic growth and oil price.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.2
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• pp.537-550
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• 2014

The actual burden of head and neck cancer in India is much greater than reflected through the existing literature and hence can be regarded as a 'tip of iceberg' situation. This has further been evident by the recent reports of 'Net-based Atlas of Cancer in India'. South-east Asia is likely to face sharp increases of over 75% in the number of cancer deaths in 2020 as compared to 2000. Since the percentage increase of Indian population has been nearly twice that of the world in last 15 years there is a likelihood of increase in cancer burden with the same proportion. The distribution of population based cancer registries is grossly uneven with certain important parts of the country being not represented at all and hence the current cancer burden is not reflected by registry data. However, the pathetic situation of health care system in major parts of the country as also emphasized by the World Bank, is not suitable to provide anywhere near accurate data on cancer burden. Head and neck cancer (including thyroid lesions) is third most common malignancy seen in both the sexes across the globe but is the commonest malignancy encountered in Indian males. Also oral cavity cancer is the most prevalent type amongst the males and one of the highest across the globe. This article reviews the latest global and national situation with an especial emphasis on head and neck cancer. Furthermore this review focuses on burden in different sub sites at national and global levels.