• Steel and Composite Structures
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• v.49 no.5
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• pp.547-570
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• 2023

In the present work, a comparative study has been carried out between power, exponential, and sigmoidal sandwich FGM plates for free vibration conditions under hygro-thermal conditions. Rules of mixture is used to determine effective material properties across the thickness for power-law and sigmoid sandwich FGM plates. Exponential law is used to plot effective material properties for exponentially graded sandwich FGM plates. Temperature and moisture dependent material properties were used during the analysis. Free vibration analysis is carried out using recently proposed finite element based HOZT. Present formulation satisfies interlayer transverse stress continuity conditions at interfaces and transverse shear stress-free conditions at the plate's top and bottom surfaces. The present model is free from any penalty or post-processing requirements. Several new results are reported in the present work, especially for unsymmetric sandwich FGM plates and exponential and sigmoidal sandwich FGM plates.

• Computers and Concrete
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• v.33 no.1
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• pp.1-11
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• 2024

Aggressive environmental conditions, and especially the acidic effects of sulfate ion penetration, have reduced the lifetime of concrete structures in some areas, especially coastal and marine areas. In this research, at first, samples made of type II and V cement were kept in a solution of magnesium sulfate (MgSO₄) for a period of 90 and 180 days, the change of appearance. Field Emission Scanning Electron Microscopy (FE-SEM) and X-Ray Diffraction (XRD), were used to analyze the microstructure and the complex mineral composition of the concrete after exposure to corrosive environments. Then solving the differential equation governing the sulfate ion penetration, which is based on the second Fick law, it has been tried to determine the concentration of sulfate ions inside the concrete. In the following, an attempt has been made to improve the prediction of sulfate ion concentration in concrete by using Crank's penetration equation. At the same time, the coefficient in the Crank's solution have been optimized by using the Particle Swarm Optimization (PSO algorithm). The comparison between the results shows that the values obtained from Crank's relation are closer to the experimental results than the equation obtained from Fick's second law and shows a more accurate prediction.

• The Korean Journal of Air & Space Law and Policy
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• v.4
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• pp.7-35
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• 1992

The expansion of air transport on a global scale with ever increasing traffic densities has brought about problems that must be solved through new multilateral mechanisms. Looking to the immediate future, air transport will require new forms of international cooperation in technical and economic areas. Air transport by its very nature should have been a counterforce to nationalism. Yet, the regulatory system in civil aviation is still as firmly rooted in the principle of national sovereignty as when it was first proclaimed at t-11e Paris Convention of 1919 and reaffirmed in the Chicago Convention. Sovereignty over the airspace has remained the cornerstone of relations between states in all respects of air transport. The importance of sovereignty over air space embodied in article 1 of the Chicago Conrenton also is responsible for restricting the authority of ICAO as an intergovernmental regulatory agency. The Orgenization, for all its extensive efforts, has only limited authority. ICAO sets standards but cannot enforce them; it devises solutions but cannot impose them. To implement its rules ICAO most rely not so much on legal requirements as on the goodwill of states. It has been forty-eight years since international community set the foundations of the international system in civil aviation action. Profound political, economic and technological changes have taken place in air transport. The Chicago Convention is living proof that staes can work together to make air transport a safe mode of travel. The law governing international civil auiation is principally based on international treaties and on other regulation agreed to by governments, for the most part through the mechanism of ICAO. The role of ICAO international standards and recommended practices and procedures dealing with a broad range of technical matters could hardly be overestimated. The organization's ability to develop these standards and procedures, to adapt them continuously to the rapid sate of change and development of air transport, should be particularly stressed. The role of ICAO in the area of the development of multilateral conventions on international air law has been successful but to a certain degree. From the modest starting-point of the Tokyo Convention, we have seen more adequate international instruments prepared within the scope of ICAO activities, adopted: the Hague Convention of 1970 for the suppression of Unlawful Seizure of Aircraft and the Montreal Convention of 1971 for the Suppression of Unlawful Acts against the Safety of Civil Aviation. The work of ICAO in the new domain of international law conventions concerning what has been loosely termed above as the criminal problems connected with international air transport, in particular the problem of armed aggression against aircraft, should be positively appreciated. But ICAO records in the domain of developing a uniform legal system of international carriage by air are rather disappointing. The problem of maintaining and developing the uniformity of this regulation exceeds the scope of interest and competence of governmental transport agencies. The expectations of mankind linked to it are too great to give up trying to restore the uniform legal system of international air carriage that would create proper conditions for its further growth. It appears that ICAO has, at present, a good opportunity for doing this. The hasty preparation of ICAO draft conventions should be definitely excluded. Every Preliminary draft convention ought to be sent to Governments of all member-States for consideration, So that they could in form ICAO in due time of their observation. The problom of harmonizing a uniform law of international air carriage with that of other branches of international transport should demand more and more of its attention. ICAO cooperation with other international arganization, especially these working in the field of international transport, should be strengthened. ICAO is supposed to act as a link and a mediator among, at times the conflicting interests of member States, serving the happiness and peace of all of the world. The transformation of the contemporary world of developing international relations, stimulated by steadily growing international cooperation in its various dimensions, political, economic, scientific, technological, social and cultural, continuously confronts ICAO with new task.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.43
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• pp.143-168
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• 2009

International Factoring transaction in Korea is different from that of financially advanced countries in terms of legal system and commercial and financial practices. As for the domestic factoring, Korean factors are only involved in advances often on a with recourse basis. With regard to the international factoring, Korean factors do not accommodate whole account receivables from clients (suppliers) but handle on a selective basis. Among Korean banks, KEXIM (Export and Import Bank of Korea) is sole factor for international transactions. Currently KEXIM and several foreign banks handle factoring provide factoring services with limitation to invoice discounting which is largely extended to large corporate names. Therefore this is far different from factoring in Europe and Americas designed for small exporters with non recourse advances. In respect of legal environment, receivable assignment is subject to debtor' acknowledge or approval of such assignment according to Civil Law Act. To remove the legal obstacles, Korean government have prepared new law which allows factor's own notification of assignment (and thereby reimbursement right) to debtor with some evidences.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.16
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• pp.59-81
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• 2001

There are two methods of quantifying the damages when the contract is avoided. One is 'concret' assessment, the other is 'abstract' assessment. The former looks to the actual cost incurred by the aggrieved party in concluding a contract for the substitute transaction, while the latter is based on the market price. The concrete method of assessment forms the starting point in the Civil Law systems. In the Common Law systems, it is likewise available. The aggrieved party is entitled to recover the difference between the cost of cover or (as the case may be) the proceeds of resale and the contract price. Both systems also recognize the abstract method of assessment. If the aggrieved party does not resell or cover, damages are equal to the difference between the price fixed by the contract and the market price. The CISG and the UNIDROIT Principles recognize expressly both concrete and abstract methods. Under the relevant articles, the aggrieved party can recover the damages assessed by one of the methods as well as any further damages such as loss of profit, incidental and consequential damages.

• Journal of Arbitration Studies
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• v.8 no.1
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• pp.55-85
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• 1998

Each of China, Taiwan, Japan and Korea is in international trade one of the major countries in Asia and has been influenced by the Chinese character culture and the Civil law system. All these countries have their own commercial dispute resolution system for international trade dispute and commercial arbitration mechanism in their countries. They are making their own effort to internationalize and improve their commercial arbitration system. Among these countries China enacted a new arbitration law already. At that time Chinese arbitration law was referred to the UNCITRAL Model Law on International Commercial Arbitration for internationalization of Chinese commercial arbitration system. China also internationalized the panel of arbitrators by increasing the foreign arbitrators of the panel of arbitrators of CIETAC. These measures adopted by China will be the model of dispute resolution and the commercial arbitration system in other major countries in Asia.

• Steel and Composite Structures
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• v.37 no.5
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• pp.621-632
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• 2020

This research deals with the study of vibrational behavior of armchair and zigzag single-walled carbon nanotubes invoking extended Love shell theory. The effects of different physical and material parameters on the fundamental frequencies are investigated. By using volume fraction for power law index, the fundamental natural frequency spectra for two forms of single-walled carbon nanotubes are calculated. The influence of frequencies against length-to-diameter ratios with varying power law index are investigated in detail for these tubes. To discretize the governing equation in eigen-value form, wave propagation approach is developed. Complex exponential functions have been used and the axial model depends on boundary condition that has been described at the edges of carbon nanotubes to calculate the axial modal dependence. Computer software MATLAB is utilized for the frequencies of single-walled carbon nanotubes and current results shows a good stability with comparison of other studies.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.29
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• pp.3-37
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• 2006

This writing is for the purpose of investigating the specific character and problem point of China arbitration system which has near 90 years history and overviewing the drift of system improvement which happens recently. The arbitration system of China which traditionally does not acknowledge ad hoc arbitration, unlike most of the other nations that employ The UNCITRAL model law and make it their own legislation, is restrictive to the parties concerned principle of private autonomy considerably. Also the independence of arbitration is delicate, because of a civil characteristic weakness of the arbitral institutions and the intervention of the courts on the arbitration procedure and award. The dual system of domestic and international arbitration which maintains after enforcement of 1994 arbitration law is often to be a primary factor interrupting the development of Chinese arbitration system and making it vulnerable to challenges. The system improvement demand of the recent time reflects this point and makes the arbitration system of China to a international standard rather than now, so it is a desirable direction for China to be as the member of the world economy to be globalization.

• Journal of the Korean Society of Industry Convergence
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• v.10 no.3
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• pp.149-155
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• 2007

Damage assessment and Damage index for RC members failed in flexure was investigated by using the nonlinear finite element analysis, included with nonlocal constitutive law, which is analyzed for the localization of the failure on the post-peak region. In the nonlcal constitutive law, The local strains obtained at gauss points were averaged over a particular length, i.e. characteristic length and it was used to evaluate the damage of RC column member. As the analysis results, The value of nonlocal strain shows less mesh sensibility. In the damage assessment, It was confirmed that evaluations of damage of RC member were able to use nonlocal compressive strain on a cover concrete and a core concrete of the member. Moreover it was confirmed that damage process for the statically indeterminate structure was able to evaluate the damage context of the component members of the structure.

• Structural Engineering and Mechanics
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• v.56 no.1
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• pp.85-106
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• 2015

Postbuckling of thick plates made of functionally graded material (FGM) subjected to in-plane compressive, thermal and thermomechanical loads is investigated in this work. It is assumed that the plate is in contact with a Pasternak-type elastic foundation during deformation. Thermomechanical non-homogeneous properties are considered to be temperature independent, and graded smoothly by the distribution of power law across the thickness in the thickness in terms of the volume fractions of constituents. By employing the higher order shear deformation plate theory together the non-linear von-Karman strain-displacement relations, the equilibrium and compatibility equations of imperfect FGM plates are derived. The Galerkin technique is used to determine the buckling loads and postbuckling equilibrium paths for simply supported plates. Numerical examples are presented to show the influences of power law index, foundation stiffness and imperfection on the buckling and postbuckling loading capacity of the plates.