• Journal of applied mathematics & informatics
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• v.38 no.1_2
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• pp.13-36
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• 2020

In this paper, we have presented a multispecies prey-predator harvesting system based on Lotka-Voltera model with two competing species which are affected not only by harvesting but also by the presence of a predator, the third species. We also assume that the two competing fish species releases a toxic substance to each other. We derive the condition for global stability of the system using a suitable Lyapunov function. The possibility of existence of bionomic equilibrium is considered. The optimal harvest policy is studied and the solution is derived under imprecise inflation in fuzzy environment using Pontryagin's maximal principle. Finally some numerical examples are discussed to illustrate the model.

• The Journal of Korean Philosophical History
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• no.23
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• pp.295-316
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• 2008

This is to study the military philosophy of Wangzhen's Commentary on Daodejing written by a famous military officer in the end of Tang Dynasty, Wangzhen. Historically, many scholars consider Laozi's Daodejing as a book on military science. Wangzhen, however, is the only person to interpret Daodejing genealogically from a military perspective. Wangzhen thinks that the fact that human beings like competing naturally causes the constant competition in the world. Human beings are born with the most outstanding spirit among all beings. But, when God created human beings, they had greed and avarice in the middle of their heart. Accordingly, human beings look for a success and a profit, and follow the wicked way, leaving the right way. The contractions among each greed and avarice bring about small or big competitions. Human beings have greed and avarice. It means human beings have emotions. As a result, the competitions in the world are not able to disappear because human beings have emotions. To win the completion human beings use weapons. According to Wangzhen, the war is the most devilish deed due to the weapon's atrocious, dangerous quality. Yet, the world's interests are decided by how efficiently the weapons are used. Consequently, the weapon techniques are worthy and play an important role in the real world. Morality, however, should be in the first priority in ruling over a country and commanding the army. The national security and the war victory could be secured when civil and military affairs have a balance. Wangzhen thinks that Laozi emphasizes "Not-Competing" as a basic solution of competition. The competition is the root cause of war and disorder. Therefore, Not-Competing is the main idea of Daodejing. Not-Competiting is a basis of Wangzhen's military philosophy as well. For Wangzhen, Not-Competing is Wuwei. Wuwei has political and military meanings at the same time. Wangzhen build up the "Not-Competing" military philosophy by applying Loazi's Daodejing to his military philosophy.

• Journal of applied mathematics & informatics
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• v.27 no.5_6
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• pp.1411-1427
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• 2009

We propose a model based on Lotka-Volterra dynamics with two competing spices which are affected not only by harvesting but also by the presence of a predator, the third species. Hyperbolic and linear response functions are considered. We derive the conditions for global stability of the system using Lyapunov function. The optimal harvest policy is studied and the solution is derived in the interior equilibrium case using Pontryagin's maximal principle. Finally, some numerical examples are discussed. The nature of variations in the two prey species and one predator species is studied extensively through graphical illustrations.

• Journal of Distribution Research
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• v.2 no.2
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• pp.153-172
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• 1997

The distribution sector is affected by a wide range of regulations. Many of these are related to health and safety, others are related to urban planning and environmental issues, whereas some mainly have an economic basis. But, regulations many be unduly restrictive, in which case they can drive up costs and ultimately prices, or they may, in some cases, reduce consumer choice. Unduly restrictive regulations could also increase costs indirectly, by reducing competition and thus lead to lower productivity growth. In the past few years, distribution sector has gone through drastic changes due to deregulation and market opening. Implementation of regulatory reforms served as an opportunity to change laws and systems which had been an obstacle to development of distribution sector. Market opening of distribution sector became a turning point to promote competition among domestic and foreign firms. However, for small and medium scale of the typical retail enterprises which were in no position to compete in terms of prices, additional facilities, and services, faced a threat of diminished trading area, and even of their existence. Because, large firms may have greater market power than small firms, as they can more easily extract favorable terms when procuring goods, and may also be able to deter entry by advertising outlays or access to the best sites. In addition, larger chain stores armied with sufficient capital dominated trading area and reduced customer's welfare by abusing their monopoly power when competing with other shops, and are often cited as an example of adverse effects of local monopoly. In order to minimize such adverse effects and to foster competition, regulatory reforms in distribution sector should set its goal to promote sound and stable distribution activities through market principle and restoring competition principle, and ultimately to boost customers welfare. Therefore, deregulation in distribution sector should be implemented in a way to promote customers welfare, eliminate entry barriers, and expand competition principle such as productivity and efficiency competition. However, it should be also recognized that deregulation of system alone is not enough to develop the distribution sector. To compete in a increasingly concentrated industry, small enterprises increasingly engage in co-operative arrangements, such as buying groups, strategic alliances or franchise agreements.

• Journal of National Security and Military Science
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• s.7
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• pp.1-24
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• 2009

This article deals with military thought in general. First I tried to distinguish 'thought' from 'theory', 'philosophy', and 'principle'. Thought means the act of thinking about or considering something, an idea or opinion, or a set of ideas about a particular subject, e.g. military affairs in the present discussion. Theory means a formal statement of the rules on which a subject of study is based or of ideas which are suggested to explain a fact or event or, more generally, an opinion or explanation. Philosophy means the use of reason in understanding such things as the nature of reality and existence, the use and limits of knowledge. Principle means a basic idea or rule that explains or controls how something happens or works. Chapter 3 summarized the characteristics of military thoughts into five points', (i) it is closely related with concrete experiences of a nation; (ii) it includes philosophical and logical arguments; (iii) it relies heavily on the political thought of a nation; (iv) it includes necessarily value-judgments; (v) it contains visions of a nation which are not only descriptions or explanations of military affairs, but also evaluations and advocacies. Chapter 4 considers the relation of international political thoughts to military thought. Throughout the history of the modem states system there have been three competing traditions of thought: the Hobbesian or realist tradition, which views international politics as a state of war; the Kantian or universalist tradition, which sees at work in international politics a potential community of mankind; and the Grotian or internationalist tradition, which views international politics as taking place within an international society. Chapter 5 considers the law of war, which is a body of law concerning acceptable justifications to engage in war (jus ad bellum) and the limits to acceptable wartime conduct (jus in bello). Among other issues, modem laws of war address declarations of war, acceptance of surrender and the treatment of prisoners of war, military necessity along with distinction and proportionality, and the prohibition of certain weapons that may cause unnecessary suffering.

• Ocean and Polar Research
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• v.31 no.1
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• pp.31-50
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• 2009

The demarcation of Maritime Boundary is directly related to the expansion of jurisdiction and the securing of resources. Resource diplomacies of the three countries Korea, China and Japan represent a major task for the national administrations : to secure resources as well as to stablize and sustain resources for future national economies. At the sea area around Korea as well, countries are fiercely competing to secure resources and to expand jurisdiction. This is evidenced by the fact that various principles and logics which are beneficial to each own country are presented through international precedents, agreement between countries and the theories of the international law scholars. They say that the conclusion of demarcation of maritime boundary for the Yellow Sea would be easy from the point that there is no dispute related to island dominion in the waters of the Korean Peninsula especially the Yellow Sea, but still we need to have a strategic approach to this issue from the point that the factors used for claiming maritime boundaries may expand the waters of a country over much. For example, the continental shelf boundary in consideration of the distribution of sedimentary deposits in the Yellow Sea which is being raised by China began from the hypothesis that the inflow of sedimentary deposits to the Yellow Sea through the rivers of China represents absolute majority, but the results of the latest studies raised questions on the hypothesis. Especially, the studies done by Martin and Yang revealed that the inflow of sedimentary deposits to the Yellow Sea from the Yellow River is approximately less than 1% of total sedimentary deposits in the Yellow Sea, and also the result of analysis on the causes and counter policy measures on the environment of Bohai, China supports the reliability of the results of such studies. From a legal aspect, the sedimentary deposits of rivers which are claimed by China represent extremely weak ground for the claim for the title of the continental shelf. The siltline claimed by China seems to be based on the Article 76-4-(a)(i) of UNCLOS. This is, however, not the definition on the title of the continental shelf but it is only a technical formula to utilize in a case where a country desires to expand the continental shelf to over 200 nautical miles. Scientific and Technical Guidelines of the Commission on the Limits of the Continental Shelf also confirm this point through the Article 2.1.2 of the Guideline. The only case in which sedimentary deposits of rivers were referred to as concrete demarcation of maritime boundary was in the which was concluded in 1986 between India and Myanmar at the Andaman Sea. In the said case, India acknowledged the boundary up to the isobath of 200m which Myanmar claimed based on the sedimentary deposits of the Irrawaddy River. It has limits as a case for acknowledging the sedimentary deposits, however, because in fact India's acknowledgment was made in exchange for the condition that Myanmar gave up the dominion of two islands which they had been claiming from India up until that time.