• Structural Engineering and Mechanics
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• 제37권6호
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• pp.671-684
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• 2011

Deciding on an optimal sensor placement (OSP) is a common problem encountered in many engineering applications and is also a critical issue in the construction and implementation of an effective structural health monitoring (SHM) system. The present study focuses with techniques for selecting optimal sensor locations in a sensor network designed to monitor the health condition of Dalian World Trade Building which is the tallest in the northeast of China. Since the number of degree-of-freedom (DOF) of the building structure is too large, multi-modes should be selected to describe the dynamic behavior of a structural system with sufficient accuracy to allow its health state to be determined effectively. However, it's difficult to accurately distinguish the translational and rotational modes for the flexible structures with closely spaced modes by the modal participation mass ratios. In this paper, a new method of the OSP that computing the mode shape matrix in the weak axis of structure by the simplified multi-DOF system was presented based on the equivalent rigidity parameter identification method. The initial sensor assignment was obtained by the QR-factorization of the structural mode shape matrix. Taking the maximum off-diagonal element of the modal assurance criterion (MAC) matrix as a target function, one more sensor was added each time until the maximum off-diagonal element of the MAC reaches the threshold. Considering the economic factors, the final plan of sensor placement was determined. The numerical example demonstrated the feasibility and effectiveness of the proposed scheme.

• Strategy21
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• 통권42호
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• pp.224-257
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• 2017

As the Trump administration withdraws the Paris Climate Agreement and shows its antipathy toward free trade, the U.S.'s soft power is most likely to weaken and its behaviors could be perceived as acts to surrender the U.S. hegemonic leadership in the world stage. Hegemonic stability theory notes that the existence of a hegemonic power contributes to international stability in the sense that it provides international public goods. A lack of the U.S's leadership in international politics, however, could be recognized as its denial of a hegemonic status. Is it intentional or accidental? The U.S's denial of hegemonic roles is the byproduct of the Trump administration's "American First" policy, not the showcase of its intention to transit hegemony to others. What is noteworthy is that China targets a niche market of hegemony as the U.S. denies its roles as the international leader. Put it another way, China attempts to ride hegemony for free when the U.S. denies its hegemonic roles accidentally. Faced with a niche market of hegemony, China has begun to accelerate its national strategy to make "Chinese Dream" come true. To that end, China promised again to keep the Paris Climate Agreement and attempts to play more active its roles in Shanghai Cooperation Organization(SCO), Asia Infra Investment Bank(AIIB), and "One Belt, One Road". Despite all these efforts, the U.S. is most likely to withdraw its denial of hegemony any time soon. The U.S's resumption of Freedom of Navigation Operations(FONOPs) could be a precursor of the return to a hegemonic power's willingness. In this vein, it is noteworthy that the South China Sea serves as a quasi-war zone for hegemonic conflict.

• 분석과 대안
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• 제2권2호
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• pp.111-141
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• 2018

By the middle of 2018 there are signs of China's entry into a new period of development, characterized by a change in the old model: "market reforms-inner-party democratization - moderate foreign policy" to another: "market reforms - Xi Jinping personality cult - offensive foreign policy." This model contains the risks of arising of the contradiction between economic freedom and political-ideological rigidity which can lead to destabilization of the political life. However, in the current positive economic dynamics, these risks may come out, rather, in the medium and long term. Today, the political situation in China remains stable - despite growing dissatisfaction in scientific expert and educational circles due to increased control over the intellectual sphere by the authorities. The need for a new redistribution of power between central and provincial authorities could potentially disrupt political stability in the medium term, but, at the moment, is not a critical negative factor. The economic situation is positive-stable. Forecasts indicate a possible increase in China's GDP in 2018 at 6.5%. At the same time, there are negative expectations in connection with the Sino-US and potentially Sino-European "trade war". In the Chinese foreign policy, as a response to Western pressure, China increasingly uses the Russian direction of its diplomacy in the expanded version of Russia + SCO. The nuance here is seen in China's adjusted approach to the SCO: first of all, not as a mechanism for cooperation with Russia, but as an organization that allows using Russia's potential for pressure on the US in the Sino-US strategic rivalry. In the second half of 2018, the Chinese economy will continue to develop steadily, albeit with unresolved traditional problems (debts of provinces and state-owned enterprises, ineffective state sector, risks on the financial and real estate market). In politics, discontent with the cult of Xi will accumulate, but without real threats to its power. Weakening in economic opposition between China and the United States is possible due to Beijing's search for compromises on tariffs, intellectual property, trade deficit. To find such trade-offs, Xi will use the so-called. "Personal diplomacy" of direct contacts with Trump.

• 의료법학
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• 제17권2호
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• pp.177-219
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• 2016

상업광고는 경쟁의 수단이자 그 자체 표현양식이기도 하다. 따라서 이는 영업의 자유(헌법 제15조)와 언론 출판의 자유(헌법 제21조 제1항)의 보호를 받는다. 영업의 자유 내지 경쟁과 관련하여서는 부정경쟁행위로서 제재되어야 하는 부당광고와 그 제한이 부당한 경쟁제한으로 오히려 금지될 수 있는 정당한 광고의 구분이 중요하다. 언론 출판의 자유 내지 표현과 관련하여서는 검열금지의 원칙(헌법 제21조 제2항)이 문제된다. 이 글에서는 이들 두 쟁점을 중심으로 (자유)전문직 광고규제, 특히 의료광고를 검토하였다. 그 결과는 다음과 같다. 첫째, (자유)전문직 광고, 특히 의료광고라 하더라도 사전심의를 받게 할 것은 아니다. 이는 검열금지가 상업광고에 대하여 적용되어야 한다는 뜻은 아니다. 검열금지를 상업광고에까지 적용하는 것은 부적절하다. 그러나 헌법재판소는 검열금지를 상업광고에 적용하고 있고, 실제로 의료광고에서 사전검열이 필요하다고 보이지도 아니한다. 사전심의를 지지하는 이는 주로 의료에 정보비대칭성이 있고, 잘못된 의료로 인한 해가 중대할 뿐 아니라 회복불가능하다는 점에서 그 근거를 찾는데, 의료법은 의료과오책임과 설명의무로 이에 대응하고 있고 의료광고가 여기에 미치는 영향은 매우 제한되어 있기 때문이다. 사전심의는 전면 폐지하거나 굳이 틀을 유지하려면 심의 받은 광고에 대한 인증제도 또는 완전한 자율규제로 전환하여야 한다. 둘째, (자유)전문직 광고, 특히 의료광고에 대하여 광고 일반보다 더 높은 규제를 가할 근거도 없다. 더 높은 수준의 규제를 가하여야 한다는 주장은 그 근거로 (자유)전문직은 윤리성, 비영리성을 갖고 있고, 특히 의료업은 국민건강보험체제에 편입되어 있는바, 경쟁이 이 체제의 안정성을 해할 수 있다는 점을 지적한다. 그러나 (자유)전문직이라 하더라도 직업윤리 등의 제약 하에 영리를 추구하고 경쟁할 수 있고, 또 실제로 하고 있으며, 의료업이 국민건강보험체제에 편입되어 있다는 사정 또한 경쟁의 수단 등에 일정한 제약을 부과할 뿐 경쟁 자체를 배제하지는 아니한다. 의료업에 대하여 일반 광고규제보다 더 엄격한 광고규제를 가하는 것은 초보의사에 대한 진입장벽으로 작용할 가능성이 높고, 그러한 점에서 경쟁제한적 행위로서 그 정당성이 의심스럽다.

• 아태비즈니스연구
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• 제12권4호
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• pp.289-297
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• 2021

Purpose - This study analyzed the correlation between economic liberalization and foreign direct investment. The purpose of this study is to seek ways to attract foreign direct investment from developing countries. Design/methodology/approach - This study analysed with observations of 19 from 2000 to 2018 using a fixed effect model, a random effect model, and a two-way fixed effect model. Findings - First, it was found that economic liberalization had a positive effect on attracting foreign direct investment in the early stages of economic liberalization. Second, it was found that economic liberalization in the deepening stage of economic liberalization had a negative effect on attracting foreign direct investment. In general, it was found that the higher the level of economic liberalization in developing countries is not accompanied by innovative changes in the industrial structure, the higher the level of economic liberalization is likely to decrease the inducement of foreign direct investment due to negative factors such as an increase in labor costs. Overall, this study approved that Economic liberalization have a non-linear (inverted U-shape) relationship with the inflow of foreign direct investment. Research implications or Originality - First, this study attempted to expand the variables for the determinants of FDI by analyzing economic factors which is a determinent of FDI. Second, economic liberalization generally has a positive effect on foreign direct investment, but it proved that it does not have only positive effects as a factor of attracting foreign direct investment in developing countries. The advantage of low wages in ASEAN countries acts as a factor for foreign direct investment, but as the degree of economic liberalization increases, the environment such as government size, guarantee of property rights, international trade freedom, fiscal soundness, and regulations change positively. On the other hand, it can be suggested that if the industrial level is less, it may lead to a loss of comparative advantage and a decrease in investment.

• 무역상무연구
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• 제22권
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• pp.173-197
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• 2004

Letter of Credit between buyer and seller in International Trade Transaction is the means of payment which makes International Trade operate smoothly by guaranteeing an exporter against non-payment and an importer against non-delivery. Therefore, the parties to a sale apply UCP500 established by the International Chamber of Commerce, in accordance with principle of the freedom of contract among the parties concerned, to look to their own legal stability. However, we may recognize some cases to have been applied principle of faith and trust, one of the dominant principles of the civil law, by the Korean Supreme Court and other cases to have not been applied that principle by the Korean Supreme Court. The Court shall apply UCP500 strictly as long as the parties concerned adopt UCP500 in view of the legal stability. In other words, in case that the Court applies principle of faith and trust to the case related to L/C, this rule - principle of faith and trust - should apply to the subject matter which have not stipulated in UCP500 under certain restriction. We suggest keeping in mind points to korean companies as follows; First, the parties to a sale shall understand L/C basis transaction and principles related to L/C deeply. Second, the exporter shall prepare documents in compliance with L/C and fulfil his or her obligation according to UCP500 and L/C related to the contract. Third, as buyer or importer, when he or she receive the shipping documents with discrepancies from the notifying bank, he or she makes him or herself clear to all the parties concerned. Fourth, as bank, she shall examine all the documents according to UCP500 and L/C related to the contract, and if any document with discrepancies, the bank, by all means, shall approach applicant first, and then decide whether to pay the credit amount to beneficiary or not to.

• 대한기계학회논문집A
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• 제20권6호
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• pp.1882-1892
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• 1996

This paper is concerned with the position control of the ond degree-of freedom manipulator using pneumatic artificial muscle actuator which is built to have a proper compliance. For t his pneumatic artificial muscle actuator though, it is difficult to make an effective control scheme due to the nonlinearity and uncertainties on the dynamics of the actuator. In this paper, a third-order equation of motion is derived for the actuator including the dynamics of the pneumatic servovalve. Later, various modeling uncertainties due to the nonlinearity and unmodeled dynamics of the servo vlave and the actuator are taken care of, as a trade-off between the closed-loop performance of the controlled system and its robustness to uncertainties. A controller using .mu. synthesis thchnique is designed, and robust performance against measurement noise, various modeling uncertainties due to the dynamics of the servo valve and actuator is achieved. The effectiveness of the proposed control methods is illustrated through simulations and experiments.

• International Journal of Control, Automation, and Systems
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• 제1권4호
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• pp.474-483
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• 2003

Belt drives provide freedom to position the motor relative to the load and this phenomenon enables reduction of the robot arm inertia. It also facilitates quick response when employed in robotics. Unfortunately, the flexible dynamics deteriorates the positioning accuracy. Therefore, there exists a trade-off between the simplicity of the control strategy to reject time varying disturbance caused by flexibility of the belt and precision in performance. Resonance of the system further leads to vibrations and poor accuracy in positioning. In this paper, accurate positioning of a belt driven mechanism using a feed-forward compensator under maximum acceleration and velocity constraints is proposed. The proposed method plans the desired trajectory and modifies it to compensate delay dynamics and vibration. Being an offline method, the proposed method could be easily and effectively adopted to the existing systems without any modification of the hardware setup. The effectiveness of the proposed method was proven by experiments carried out with an actual belt driven system. The accuracy of the simulation study based on numerical methods was also verified with the analytical solutions derived.

• Smart Structures and Systems
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• 제22권4호
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• pp.469-479
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• 2018

The present research study utilizes a multi-objective optimization method for Pareto optimization of an eight-degree of freedom full vehicle vibration model, adopting a non-dominated sorting genetic algorithm II (NSGA-II). In this research, a full set of ride comfort as well as ride safety parameters are considered as objective functions. These objective functions are divided in to two groups (ride comfort group and ride safety group) where the ones in one group are in conflict with those in the other. Also, in this research, a special optimizing technique and combinational method consisting of weighted sum method and Pareto optimization are applied to transform Pareto double-objective optimization to Pareto full-objective optimization which can simultaneously minimize all objectives. Using this technique, the full set of ride parameters of three dimensional vehicle model are minimizing simultaneously. In derived Pareto front, unique trade-off design points can selected which are non-dominated solutions of optimizing the weighted sum comfort parameters versus weighted sum safety parameters. The comparison of the obtained results with those reported in the literature, demonstrates the distinction and comprehensiveness of the results arrived in the present study.

• 대한전기학회논문지:시스템및제어부문D
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• 제49권1호
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• pp.18-25
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• 2000

In the two-mass servo system driving a load through a flexible shaft, a shaft torsional vibration is often generated. PI controller has been generally used is speed control of such system because of the simplicity of structure and related theory. This paper presents the inertia ratio of the PI servo control system which can be designed by using optimal pole assignment method is fixed. Therefore, it's difficult to obtain the desired control characteristics for different systems only by PI control algorithm. To solve this problems the two-mass speed control system with PID controller is designed by using pole assignment method and an optimum PID parameters are derived by evaluating ITAE(Integral of time multiplied by the absolute error) performance index. But this design method has some problems due to a trade-off between the fast command following property and the attenuation of disturbances and vibrations. In this paper, 2-DOF PID control method which satisfies the command following property, the reduction of overshoot and the property of disturbance rejection at the same time is proposed. This is a practical speed controller using the desired value filter and the feedforward gain. From several simulations, it's clarified that the proposed 2-DOF PID controller is useful for the two-mass system, in comparison with the conventional PID controller.