• Management Science and Financial Engineering
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• v.9 no.1
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• pp.11-27
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• 2003

In this study, we propose a mathematical model based on the graph theory for the wavelength assignment problem arising in the design of SDH (Synchronous Digital Hierarchy) over WDM (Wavelength Division Multiplexing) ring networks. We propose a branch- and -price algorithm to solve the suggested models effectively within reasonable time in realistic SDH over WDM ring networks. By exploiting the structure of ring networks, we developed a polynomial time algorithm for efficient column generation and a branching rule that conserves the structure of column generation. In a computer simulation study, the suggested approach can find the optimal solutions within reasonable time and show better performance than the existing heuristics.

• Journal of Information Technology Services
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• v.9 no.3
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• pp.107-121
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• 2010

In this paper, we present a frequency reassignment problem (FRP) that arises when we install new base stations or reconfigure radio networks to increase the capacity or to expand service area. For this problem, we develop an integer programming (IP) model, and develop cutting planes to enhance the mathematical representation of the model. Also, we devise an effective tabu search algorithm to obtain tight upper bounds within reasonable time bounds. Computational results exhibit that the developed cutting planes are effective for reducing the computing time as well as for increasing lower bounds. Also, the proposed tabu search algorithm finds a feasible solution of good quality within reasonable time bound.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.12
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• pp.429-460
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• 1999

The letter of credit is quintessentially international. In the absence of international legal system, a private system based on banking practices has evolved, commanding the adherence of the international letter of credit community and providing the foundation of th reputation of this instrument. To maintain this international system, it is vital that international standard banking practice should not be subject to local interpretations that misconstrue or distort it. The UCP is a formulation of international standard banking practice. It is neither positive law nor a "contract term" in any traditional sense and its interpretation must be consonant with its character as a living repositary of international understanding in this field. As a result, the interpretation and application of specific articles of the UCP must be consistent with its evolving character and history and with the principles upon which sound letter of credit practice is predicated. This study, especially, focuses on article 13 and article 14 of the UCP500. Article 13(b) of UCP500 stipulates that banks will have a reasonable time, not to exceed seven days, to examine documents to determine whether they comply facially with the terms of the credit. The seven-day provision is not designed as a safe harbor, because the rule requires the issuer to act within a reasonable time. But, by virtue of the deletion of the preclusion rule in the document examination article in UCP500, however, seven days may evolve as something of a safe harbor, especially for banks that engage in strategic behavior. True, under UCP500 banks are supposed to examine documents within a reasonable time, but there are no consequences in UCP500 for a bank's violation of that duty. It is only in the next provision. Courts might read the preclusion more broadly than the literal reading mentioned here or might fashion a common-law preclusion rule that does not require a showing of detriment. Absent that kind of development, the change in the preclusion rule could have adverse effects on the beneficiary. The penalty, strict estoppel or strict preclusion, under UCP500 and 95UCC differs from the classic estoppel. The classic estoppel rule requires a beneficiary to show three elements. 1. conduct on the part of the issuer that leads the beneficiary to believe that nonconforming documents do conform; 2. reasonable reliance by the beneficiary; and 3. detriment from that reliance. But stict preclusion rule needs not detrimental reliance. This strict estoppel rule is quite strict, and some see it as a fitting pro-beneficiary rule to counterbalance the usually pro-issuer rule of strict compliance.

• Journal of Advanced Marine Engineering and Technology
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• v.13 no.1
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• pp.57-68
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• 1989

This paper treats the analytical and experimental studies on the improvement of commutating circuit for the speed control of DC motor. A simple circuit composed of R, L and C elements is proposed here for switching off power SCR carrying the load current. The real important in this chopper circuit is to determine the reasonable values of commutating circuit constants. In this paper, the reasonable values of the commutating circuit constants are basically determined on a view point of commutating performances in the given circuit model and must satisfy the following conditions. The first, the peak commutating current should be larger than the anticipated maximum load current. The second, the circuit turn-off time (tc) must be longer than the SCR turn-off time (tq). The third, the resistor should be enough large to permit the current to be neglected in the analysis of the commutation circuit, as well as be enough small to permit to charge the capacity voltage (Ec) to the half the value of source voltage (E) before the next communication cycle is initiated. The last, the period of chopping signal must be the least possible multiple of the damping vibration period of commutating circuit. The improved chopper circuit used in the experiment under unloaded condition was composed to meet the reasonable conditions mentioned above, and a successful commuting performance was achieved without failure. Several types of microprocessor having a different value of CPU speed individually have been applied to the experiment under the loaded conditions. Also it shows that the faster the speed of CPU is, the more stable the commutation turns out.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2008.04a
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• pp.231-234
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• 2008

Each corporation isn't consistent because of offering specific information for publicity. It spends considerable labor force and time surfing of the material information and choosing need material. That's the reason it's different with material information and choice system between production and marketing corporation. Among lots of material information, some of them are used by offering material information simplify. So it is demanded necessity of reasonable material choice system. That system helps it choose a material more easily. So we studied about the information retrieval system of reasonable material choice through the study about assortment system of material information and material choice method. It's the basic study for the suggestion of reasonable material choice system. According to this study, if that system is suggested and realized, we can overcome from the system of typical and repeatable at every course of architecture during several times. It will be helpful to increase about the productivity of architecture as the minimization of time, labor, resource and cost for the material choice.

• Korean Journal of Organic Agriculture
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• v.20 no.4
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• pp.543-561
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• 2012

This work is for reasonable valuation method of environmental-friendly and organic company. Reasonable valuation method is principal for the sound development, the reasonable investment and the growth of stock market. This study proposes valid valuation and method for environmental-friendly and organic company. The author selected 4 companies from certificate list of environmental-friendly and organic food and LOHAS (Lifestyles Of Health And Sustainability) food of Korean standards association. Applying financial audit report of 5 years, the author output 5 variables from each companies by using Growth Option model of Real Option model. And the author valuated companies by adding option value calculated with these variables and residual value discounted with cash flow discounted method. Company values from ROV model were 1.71 time higher than DCF model. This results show that the value of environmental-friendly and organic food company may own high option premium, that is the growth factor.

• Journal of Korea Multimedia Society
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• v.8 no.12
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• pp.1589-1596
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• 2005

The imprecise real-time system provides flexibility in scheduling time-critical tasks. Most scheduling problems of satisfying both 0/1 constraint and timing constraints, while the total error is minimized, are NP complete when the optional tasks have arbitrary processing times. Liu suggested a reasonable strategy of scheduling tasks with the 0/1 constraint on uniprocessors for minimizing the total error. Song et al suggested a reasonable strategy of scheduling tasks with the 0/1 constraint on multiprocessors for minimizing the total error. But, these algorithms are all off-line algorithms. On the other hand, in the case of on line scheduling, Shih and Liu proposed the NORA algorithm which can find a schedule with the minimum total error for a task system consisting solely of on-line tasks that are ready upon arrival. But, for the task system with 0/1 constraint, it has not been known whether the NORA algorithm can be optimal or not in the sense that it guarantees all mandatory tasks are completed by their deadlines and the total error is minimized. So, this paper suggests an optimal algorithm to search minimum total error for the imprecise on-line real-time task system with 0/1 constraint. Furthermore, the proposed algorithm has the same complexity, O(N log N), as the NORA algorithm, where N is the number of tasks.

• Journal of Korean Society for Quality Management
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• v.44 no.2
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• pp.373-388
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• 2016

Purpose: This paper suggests a hierarchical time delay model to evaluate failure risks in FMEA(failure modes and effects analysis). In place of the conventional RPN(risk priority number), a more reasonable and objective risk metric is proposed under hierarchical failure cause structure considering time delay between a failure mode and its causes. Methods: The structure of failure modes and their corresponding causes are analyzed together with the time gaps between occurrences of causes and failures. Assuming the severity of a failure depends on the length of the delayed time for corrective action, a severity model is developed. Using the expected severity, a risk priority metric is defined. Results: For linear and quadratic types of severity, nice forms of expected severity are derived and a meaningful metric for risk evaluation is defined. Conclusion: The suggested REM(risk evaluation metric) provides a more reasonable and objective risk measure than the conventional RPN for FMEA.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.69
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• pp.63-84
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• 2016

Article 77 of CISG requires an aggrieved party, the promisee, claiming damages to take reasonable measures to mitigate losses. The reasonable measures required hereunder are limited to those that can be expected under the circumstances having regard to the principle of good faith. When taking such measures, the aggrieved party must do so within a reasonable time under the circumstances. The expenses incurred in taking such measures are recoverable from the promisor. If the aggrieved party fails to do so, the damages recoverable from the promisor are reduced in the amount the loss that should have been mitigated. The aggrieved party's duty to mitigate damages applies to claim for damages only. That is, the violation of this duty should not be invoked against other remedies available under CISG, such as the right to claim specific performance, the right to claim for the price or the right of reduction of price. In practice, under the provision of article 77, the aggrieved party, the seller or the buyer, is often required to enter into a substitute transaction as a measure to mitigate losses and many cases involving a substitute transaction are internationally reported. Therefore this paper intends to provide a certain understanding of the aggrieved party's duty to take measures to mitigate losses based on such cases reported.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.10
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• pp.1390-1396
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• 2013

The paper estimated the reasonable market price of lead-acid battery energy storage system (BESS) intended for demand management of electricity customers. As time-of-use (TOU) tariffs have extended to a larger number of customers and gaps in the peak and off-peak rates have gradually risen, deployment of BESS has been highly needed. However, immature engineering techniques, lack of field experiences and high initial investment cost have been barriers to opening up ESS markets. This paper assessed electricity cost that BESS operation could save for customers and, based on the possible cost savings, estimated reasonable prices at which BESSs could become a more prospective option for demand management of customers. Battery scheduling was optimized to maximize the electricity cost savings that BESS would possibly achieve under TOU tariffs conditions. Basic economic factors such as payback period and return on investment were calculated to determine reasonable market prices. Actual load data of 12 industrial customers were used for case studies.