• Title/Summary/Keyword: efficient domination

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Some Cycle and Star Related Nordhaus-Gaddum Type Relations on Strong Efficient Dominating Sets

  • Murugan, Karthikeyan
    • Kyungpook Mathematical Journal
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    • v.59 no.3
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    • pp.363-375
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    • 2019
  • Let G = (V, E) be a simple graph with p vertices and q edges. A subset S of V (G) is called a strong (weak) efficient dominating set of G if for every $v{\in}V(G)$ we have ${\mid}N_s[v]{\cap}S{\mid}=1$ (resp. ${\mid}N_w[v]{\cap}S{\mid}=1$), where $N_s(v)=\{u{\in}V(G):uv{\in}E(G),\;deg(u){\geq}deg(v)\}$. The minimum cardinality of a strong (weak) efficient dominating set of G is called the strong (weak) efficient domination number of G and is denoted by ${\gamma}_{se}(G)$ (${\gamma}_{we}(G)$). A graph G is strong efficient if there exists a strong efficient dominating set of G. In this paper, some cycle and star related Nordhaus-Gaddum type relations on strong efficient dominating sets and the number of strong efficient dominating sets are studied.

LINEAR AND NON-LINEAR LOOP-TRANSVERSAL CODES IN ERROR-CORRECTION AND GRAPH DOMINATION

  • Dagli, Mehmet;Im, Bokhee;Smith, Jonathan D.H.
    • Bulletin of the Korean Mathematical Society
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    • v.57 no.2
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    • pp.295-309
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    • 2020
  • Loop transversal codes take an alternative approach to the theory of error-correcting codes, placing emphasis on the set of errors that are to be corrected. Hitherto, the loop transversal code method has been restricted to linear codes. The goal of the current paper is to extend the conceptual framework of loop transversal codes to admit nonlinear codes. We present a natural example of this nonlinearity among perfect single-error correcting codes that exhibit efficient domination in a circulant graph, and contrast it with linear codes in a similar context.

New formula in domination theory and it's application for reliability analysis (Domination이론에서의 새로운 식과 이의 신뢰성계산에 대한 적용)

  • 이광원;이일재;강신재
    • Journal of the Korean Society of Safety
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    • v.11 no.1
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    • pp.16-26
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    • 1996
  • In a series of original papers, [1-17] efficient methods and algorithms have been presented, for the exact solution of many reliability problems represented by binary networks. A starting point of these methods was the concept of domination, firstly introduced in ,elation with reliability problems in [2]. It's application to directed networks resulted in the development of a topological formula for the classical problem of the two terminal reliability. This result was extended later to the all-terminal and the k-terminal reliability problems. All papers mentioned above use a path oriented representation for the network topology. In practical applications, however, it is common and often advantageous to work with cut sets. This article considers the Domination theory for reliability problem of a network. Some topological formula are derived and the power and the application of this formula are shown through the alternative proof of topological formula of A. Satyanarayana [2].

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SOME CHARACTERIZATIONS OF DOUBY CHORDAL GRAPHS

  • Kim, Chang-Hwa
    • Journal of applied mathematics & informatics
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    • v.5 no.1
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    • pp.65-72
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    • 1998
  • Many optimization problems like domination and Steiner tree are NP-complete on chordal graphs but can be solved in polyno-mial time on doubly chordal graphs. Investigating properties of dou-bly chordal graphs probably help to design efficient algorithms for the graphs. We present some characterizations of dobly chordal graphs which are based on clique matrices and neighborhood matrics also men-tioned how a doubly perfect elimination ordering of a doubly chordal graph can be computed from the results.

COMPUTATION OF A (CANONICAL) DOUBLY PERFECT ELIMINATION ORDERING OF A DOUBLY CHORDAL GRAPH

  • Lee, Mahn-Hoon;Kim, Chang-Hwa
    • Journal of applied mathematics & informatics
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    • v.5 no.2
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    • pp.329-336
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    • 1998
  • The class of doubly chordal graphs is a subclass of chordal graphs and a superclass of strongly chordal graphs which arise in so many application areas. Many optimization problems like domination and Steiner tree are NP-complete on chordal graps but can be solved in polynomial time on doubly chordal graphs. The central to designing efficient algorithms for doulby chordal graphs is the concept of (canonical)doubly perfect elimination orderings. We present linear time algorithms to compute a (canonical) double perfect elimination ordering of a doubly chordal graph.

Food of Maghreb -Algerian food in particular- (마그레브(Maghreb)의 식문화 -알제리아를 중심으로-)

  • Chun, Hui-Jung
    • Journal of the Korean Society of Food Culture
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    • v.11 no.5
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    • pp.651-661
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    • 1996
  • Algeria is located at the Mediterranean coast of north Africa, 90% of its population is concentrated in the coastal area which is mainly devoted to agriculture. Highland steppe and vast desert climate have determined its food culture. Long arab domination has influenced food of Algeria which has also undergone certain impact of Spanish, Turkish and French occupation. A variety of agricultural products, vegetables, fruits, spices and herbs have determined cooking method and food combination of Algeria. It use neither pork nor alcohol. Its main food consists of bread made from wheat flour and couscous cooked with semoule, Mechuwi, roast lamb and chorba, mixed soup are also typical foods of this region. For climatic reason lamb and chicken are prefered. Energy efficient method is applied to cooking through using oil for saute and water for boiling. Under european influence, Algerian salad used dressing for leaf vegetables, root and other kind vegetables were boiled. Serving with cake and cookies as dessert may possibly be the influence from the French occupation. The cake and cookie are made of wheat flour or other grain flour and take a specific form to be fried sweet with honey. Herbs and spices are widely used in cooking which are easily cultivated in household: mint, basil, rosemary, bayleaf, thyme, sage, fennel, marjoram, coriander, celery. Garlic, onion, piment, red pepper, cinammon are also widely used in an ordinary cooking. Reasonable food combination and economic cooking method could be subject of Algerian food study.

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Portfolio Optimization of Diversified Investments with Minimum Risk Asset and Non-Positive Correlation Assets (최소위험 종목과 비양의 상관관계를 갖는 종목들 분산투자 포트폴리오 최적화)

  • Lee, Sang-Un
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.22 no.1
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    • pp.103-110
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    • 2022
  • This paper deals with portfolio optimization problem that you could lower the total risk of an investment portfolio by adding risky assets to the mix than the minimum risk of single asset. Popular Markowitz's mean-variance(MV) model construct the portfolio with the point in the efficient frontier using principle of domination where the variance is minimized for a given mean return. While this paper suggest the portfolio with minimum risk asset with non-positive(negative and uncorrelated) correlation assets to it. As a result of experiments, the proposed method shows lower risk(standard deviation) than MV.

Race and Politics in Brazil: Occurrence, Development, Characteristics (브라질의 인종과 정치: 발생, 전개, 특징)

  • Kim, Dal-Kwan
    • Iberoamérica
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    • v.21 no.1
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    • pp.1-55
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    • 2019
  • In Brazil, racism exists without the clear definition of race. In other words, because there is racism without a clear concept of race, racial issues are complicated in Brazil. Racism is not just a social problem. It is, above all, a political problem that arises from economic separation, exclusion, and marginalization. From the enlargement process of European colonialism, racism has been the most profound and efficient way of governance of social, material, psychological and political domination of Brazil. From this perspective, this study seeks to research racism in Brazil as a race politics. In conclusion, racial discrimination and racial inequality exist in Brazil. Thus, to study the racial discrimination and racial inequalities in Brazil, Chapter 2 examines the origins of racial politics in Brazil. Chapter 3 explores the relations of Brazilian society and races. Chapter 4 examines Black's resistance to racism as a black movement in Brazil. The first half of Chapter 5 looks at 'racial inequality in Brazil' and the latter sees 'racism in Brazil'. Chapter 6, as a conclusion, discusses the challenges and limitations of racial politics in Brazil.

Recent Developments in Space Law (우주법(宇宙法)의 최근동향(最近動向))

  • Choi, June-Sun
    • The Korean Journal of Air & Space Law and Policy
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    • v.1
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    • pp.223-243
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    • 1989
  • The practical application of modern space science and technology have resulted in many actual and potential gains of mankind. These successes have conditioned and increased the need for a viable space law regime and the challenge of space has ultimately led to the formation of an international legal regime for space. Space law is no longer a primitive law. It is a modern law. Yet, in its stages of growth, it has not reached the condition of perfection. Therefore, under the existing state of thing, we could carefully say that the space law is one of the most newest fields of jurisprudence despite the fact that no one has so far defined it perfectly. However, if space law can be a true jurisprudential entity, it must be definable. In defining the space law, first of all, the grasp of it's nature iis inevitable. Although space law encompasses many tenets and facets of other legal discriplines, its principal nature is public international law, because space law affects and effects law relating intercourse among nations. Since early 1960s when mankind was first able to flight and stay in outer space, the necessity to control and administrate the space activities of human beings has growingly increased. The leading law-formulating agency to this purpose is the United Nation's ad hoc Committee on Peaceful Uses of Outer Space("COPUOS"). COPUOS gave direction to public international space law by establishing the 1963 Declaration of Legal Principles Governing the Activities of the States in the Exploration and Use of Outer Space("1963 Declaration"). The 1963 Declaration is very foundation of the five international multilateral treaties that were established successively after the 1963 Declaration. The five treaties are as follows: 1) The Treaty on Principles Governing the Activities of States in the Exploration and Use of Outer Space including Moon and other Celestial Bodies, 1967. 2) The Agreement on the Rescue of Astronauts, the Return of Astronauts, and the Return of Objects Launched into Outer Space, 1968. 3) The Convention on International Liability for Damage Caused by Space Objects, 1972. 4) The Convention on Registration of Objects Launched into Outer Space, 1974. 5) The Agreement Governing Activities of States on the Moon and Other Celestial Bodies: Moon Treaty, 1979. The other face of space law is it's commercial aspect. Space is no longer the sole domination of governments. Many private enterprise have already moved directly or indirectly into space activities in the parts such as telecommunications and space manufacturing. Since space law as the public international law has already advanced in accordance with the developments of space science and technology, there left only a few areas untouched in this field of law. Therefore the possibility of rapid growth of space law is expected in the parts of commerical space law, as it is, at this time, in a nascent state. The resources of the space environment are also commercially both valuable and important since the resources include the tangible natural resources to be found on the moon and other celestial bodies. Other space-based resources are solar energy, geostationary and geosynchronous orbital positions, radio frequencies, area possibly suited to human habitations, all areas and materials lending themselves to scientific research and inquiry. Remote sensing, space manufacturing and space transportation services are also another potential areas in which commercial. endeavors of Mankind can be carried out. In this regard, space insurance is also one of the most important devices allowing mankind to proceed with commercial space venture. Thus, knowlege of how space insurance came into existence and what it covers is necessary to understand the legal issues peculiar to space law. As a conclusion the writer emphasized the international cooperation of all nations in space activities of mankind, because space commerce, by its nature, will give rise many legal issues of international scope and concern. Important national and world-community interests would be served over time through the acceptance of new international agreements relating to remote sencing, direct television broadcasting, the use of nuclear power sources in space, the regularization of the activities of space transportation systems. standards respecting contamination and pollution, and a practical boundary between outer space and air space. If space activity regulation does not move beyond the national level, the peaceful exploration of space for all mankind will not be realized. For the efficient regulation on private and governmental space activities, the creation of an international space agency, similar to the International Civil Aviation Organization but modified to meet the needs of space technology, will be required. But prior to creation of an international organization, it will be necessary to establish, at national level, the Office of Air and Space Bureau, which will administrate liscence liscence application process, safety review and sale of launch equipment, and will carry out launch service.

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