• International Journal of Naval Architecture and Ocean Engineering
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• v.12 no.1
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• pp.910-917
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• 2020

In fire suppression, continuous delivery of water or foam to the fire source is essential. The present study concerns fire suppression in a ship under sea condition, by introducing reinforcement learning technique to aiming of fire extinguishing nozzle, which works in a ship compartment with six degrees of freedom movement by irregular waves. The physical modeling of the water jet and compartment motion was provided using Unity 3D engine. In the reinforcement learning, the change of the nozzle angle during the scenario was set as the action, while the reward is proportional to the ratio of the water particle delivered to the fire source area. The optimal control of nozzle aiming for continuous delivery of water jet could be derived. Various algorithms of reinforcement learning were tested to select the optimal one, the proximal policy optimization.

• Structural Engineering and Mechanics
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• v.82 no.2
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• pp.259-270
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• 2022

The paper investigates the residual stresses arising in a thermoviscoelastic cylinder as a result of layer-by-layer deposition of material on its lateral surface. Internal stresses are caused by incompatible deformations that accumulate in the assembly as a result of joining parts with different temperatures. For the analysis of internal stresses, an analytical solution to the axisymmetric quasi-static problem of thermoelasticity for a growing cylinder is constructed. It is shown that the distribution of residual stresses depends on the scenario of the surfacing process. In this case, the supply of additional heat to the growing body can significantly reduce the unevenness of temperature fields and reduce the intensity of residual stresses. The most effective is uneven heating, which can be realized, by the action of an alternating current with a tunable excitation frequency. The temperature and residual stresses fields on the growing surface is analyzed numerically for Titanium and Copper materials.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.23
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• pp.71-91
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• 2004

The purpose of this paper is to examine the effects and problems of acceptance with modifications according to CISG Art. 19, comparing with UCC ${\S}2-207$. First of all this author raised two legal issues encountered when there is an acceptance with modifications. Scenario one is as follows : "Before either party has taken further action, there is a rise or a fall in the price of goods, was there a binding contract ?" The UCC rules provide for a contract if a purchaser sends out a purchase order and the seller sends back a sales acknowledgement form, and the items on the front(the price, description, and quantity) match up. The CISG on the other hand, is that most of the terms and conditions on the backs of the forms are important. Therefore, if they are different, there should not be a contract. Scenario two is as follows : "There has been performance, A disputes arises. What terms and conditions apply ?" The CISG and the UCC will probably lead to different results in the event the parties exchange conflicting forms and subsequently perform. Assuming that the offeree's reply contains terms that are materially different from the offer, the UCC provides that the resulting contract will include only those terms on which the writings of the parties agree, excluding conflicting terms. The CISG treats the material additions as a counter-offer and, in accordance with Art. 18, the offeree's performance may be regarded as an acceptance of a contract containing all of the offeror's terms ; or the offeror's performance may be regarded as an acceptance of a contract containing all of the offeree's terms. Second, this author raised three problems in the Art. 19 as follows ; 1) It is very difficult in practical application to decide what is material alterations even if the CISG lists material terms as an example. 2) There is a possibility for the offeror to speculate in the circumstance of market fluctuation as he has a change to object to the discrepancy in the offeree's reply. 3) There is also a possibility of inducement for the offeror or the offeree to send its own reply as a last shot.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.3
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• pp.1337-1345
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• 2012

The principle of Effective Based Operation applied to the Korean Theater resulted in measurable effects to win the minimum battle. Based on the finding, this study recommends the effect analysis methodology under the V-C interoperability system to acquire a weapon system. This method is followed as below; to confirm the effect data on the organized weapon system, to set MOE, MOP and effect considering the purpose of the analysis, to apply the appropriate operational concept and scenario on the weapon system, and then the available C Model is after action reviewed, adjusted, and given feedback. The V-C interoperability system enables to perform the real-time combat experiment under the virtual synthesized battlefield circumstances. The defensive battle organization and displacement of the future anti-tank guided weapon system was considered in the modeling process. Scenario was written, which encompasses company-level units and the battalion-level operation. Then the available AWAM was embodied and effect-analyzed, which formed the foundation of SBA.

• Journal of Environmental Health Sciences
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• v.41 no.3
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• pp.191-202
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• 2015

Objectives: Promotion of food safety/eradicating adulterated food has been listed as one of the four major issues recently identified for action by the Korean government. Due to the related seriousness, the food industry has been encouraged to take steps to restore consumer confidence. In order to set guidelines for the creation of manuals for the response to a food safety crisis by the food industry, this study provided a suggested organization for a crisis response team and operating procedures for crisis response activities. Methods: The prototypes of an organizational structure and a set of standard procedures for a crisis response system were provided. Results: The results of the study suggested that a crisis response team should be comprised of four divisions of responsibility: information analysis, site response, communication and operational support. The organization chart and the role and functions for each division of the crisis response team should be indicated. Response activities will be more effective when the team features multi-disciplined staffing, such as public relations, food safety/technology/quality, sales/marketing, purchasing, production, distribution/logistics, regulatory affairs/legal, and consumer service specialists. This study created a flow chart for the total crisis response system, which included crisis and normal situations. A crisis response team should be continuously operated for both crisis and normal conditions. This study also suggested a scenario to explain the procedures for crisis response activities. Conclusion: In order to cope more effectively with a food safety crisis, the organizational structure and its functions should be defined clearly, and a detailed set of standard procedures for response activities should be offered.

• Journal of Korean Philosophical Society
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• v.130
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• pp.109-134
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• 2014

In (Advaita) $Ved{\bar{a}}nta$ although human beings are destined to have a pessimistic starting point in life, their goal of life is to become a Perfect Being which is called 'Liberation' (mokṣa) by self-transcendence. This human goal together with several means are accepted by $Ved{\bar{a}}nta$ as solely valuable thing in the life. In this way there must be a self-recognition of his own value in the process of Liberation, through which one recognizes his own true nature i.e. ${\bar{A}}tman$. ${\bar{A}}tman$ is clearly defined to be 'Existence, Consciousness, Bliss' (Being, Illumination, Good), and this definition is made with the view of revealing that It is ultimate foundation and source of human beings ontologically, epistemologically and axiologically. However, as $Ved{\bar{a}}ntic$points of view on human goal are not without critical limitations, it may be necessary to revaluate 'the process of self-inquiry' devised to achieve human goal. Inquiry is, first of all, an accepting process of what is given in $Ved{\bar{a}}nta$ as the scenario that gives rise to most actual result, then, a performing and verifying process of that scenario in one's own experience consistently. In this process, a shift of action from worldly life to unworldly life is what is called 'self-adjustment', a removal of 'the self in excess' through knowledge of the real Self is what is called 'simplification of the self', and at the end of simplification a state of ultimate Self is 'Liberation'. Therefore, the inquiry of $Ved{\bar{a}}nta$ into human goal can be summarized as following formula; 'good action = self-adjustment' ${\rightarrow}$ 'good knowledge = simplification of the self' ${\rightarrow}$ 'Liberation = ultimate Self'.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37A no.11
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• pp.979-985
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• 2012

The design of an efficient scheduler is a key design factor in IEEE 802.16m systems, in order to support services with various QoS smoothly. Although conventional studies of schedules have been suggested, those had problems that are not able to satisfy the delay condition and make the through-put declined, because they only focused on a specific action scenario rather than reflecting practical action scenarios which have real-time and non-real-time traffics variously. In this paper, an efficient uplink scheduling algorithm is proposed for IEEE 802.16m system by introducing the concepts of Virtual Time(VT) and Virtual Finish Time(VFT) based priority determination, and separate buffers for each QoS class in the mobile terminal. Simulation results showed that the proposed scheme had satisfied the delay requirement of real-time services even with improved throughput performance compared to conventional methods.

• Journal of the Korean Society of Safety
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• v.33 no.6
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• pp.136-143
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• 2018

In this study, we conducted a pilot study on the multiple spurious operations (MSO) analysis in the fire probabilistic safety assessment (PSA) of domestic nuclear power plant (NPP) to identify the degree of influence of the operator actions used in the MSO mitigation strategies. The MSO scenario of the domestic reference NPP selected for this study is refueling water tank (RWT) drain down event. It could be caused by spurious operations of the containment spray system (CSS) of the reference NPP. The RWT drain down event can be stopped by the main control room (MCR) operator actions for stopping the operation of CSS pump or closing the CSS motor operated valve if the containment spray actuation signal (CSAS) is spuriously actuated. Outside the MCR, it can be stopped by operator actions for closing the CSS manual valves or motor operated valve or stopping the operation of CSS pump. The quantification result of a fire PSA model that takes into account all recovery actions for the RWT drain down event lead to risk reduction by about 95%, compared with quantification result of fire PSA model without considering them. Among the various operator actions, the recovery action for the spurious CSAS operations and the operator action for the manual valve are identified as the most important operator actions. This study quantitatively showed the extent to which the operator actions used as MSO countermeasures have affected the fire PSA quantification results. In addition, we can see the rank of importance among the operator recovery actions in quantitative terms.

• Steel and Composite Structures
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• v.41 no.5
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• pp.663-679
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• 2021

To elucidate the differences in the collapse behavior between a single-story beam-column assembly and multi-story frame, two 1/3-scale two-bay composite frames, including a single-story composite beam-column assembly and a three-story composite sub-frame, were designed and quasi-statically tested. The load-displacement responses, failure modes, and internal force development of the two frames were analyzed and compared in detail. Furthermore, the resistance mechanisms of the two specimens were explored, and the respective contributions of different load-resisting mechanisms to the total resistances were quantitatively separated to gain deeper insights. The experimental tests indicated that Vierendeel action was present in the two-dimensional multi-story frames, which led to an uneven internal force distribution among the three stories. The collapse resistance of TSDWA-3S in the flexural stage was not significantly increased by the structural redundancy provided by the additional story, as compared to that of TSDWA-1S. Although the development of the load response was similar in the two specimens at flexural stage, the collapse mechanisms of the multi-story composite frame were much more complicated than those of the single-story beam-column assembly, and the combined action between stories was critical in determining the internal force redistribution and rebalancing of the remaining structure.

• Journal of Information Technology Services
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• v.19 no.3
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• pp.151-163
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• 2020

This paper describes a study on the FRACAS(Failure Reporting Analysis and Corrective Action System)-based dependability control platform for domestic urban railway trains. There are more demands for the verification of the dependability of trains as it becomes a regulation for train manufacturers to verify the dependability recently. Train manufacturers as well as railway operators need a effective FRACAS solution to perform the verification of the dependability. Yet current FRACAS solutions have limitations to support the verification processes effectively. This paper addresses the issues of current FRACAS solutions and suggests a FRACAS framework designed for the domestic urban railway trains. Service failure scenarios are standardized using the proposed availability model to implement a more user-friendly and reliable platform. A new FRACAS-based platform for the dependability control (SCARF^®) has been developed to implement the suggested framework. The detail interfaces and functions of the platform are explained. The SCARF^® platform is expected to engage the increasing demands for the dependability control successfully enhancing the reliability, maintainability, availability and safety of domestic urban railway trains eventually.