• Advances in aircraft and spacecraft science
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• v.7 no.6
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• pp.537-551
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• 2020

Investigation of leading edge impingement cooling for first stage rotor blades in an aero-engine turbine, its effect on rotor temperature and trailing edge wake loss have been undertaken in this study. The rotor is modeled with the nozzle for attaining a more accurate simulation. The rotor blade is hollowed in order for the coolant to move inside. Also, plenum with the 15 jet nozzles are placed in it. The plenum is fed by compressed fresh air at the rotor hub. Engine operational and real condition is exerted as boundary condition. Rotor is inspected in two states: in existence of cooling technique and non-cooling state. Three-dimensional compressible and steady solutions of RANS equations with SST K-ω turbulent model has been performed for this numerical simulation. The results show that leading edge is one of the most critical regions because of stagnation formation in those areas. Another high temperature region is rotor blade tip for existence of tip leakage in this area and jet impingement cooling can effectively cover these regions. The rotation impact of the jet velocity from hub to tip caused a tendency in coolant streamlines to move toward the rotor blade tip. In addition, by discharging used coolant air from the trailing edge and ejecting it to the turbines main flow by means of the slot in trailing edge, which could reduce the trailing edge wake loss and a total decrease in the blade cooling loss penalty.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.6
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• pp.1881-1900
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• 2014

Since 802.11 wireless LANs are so widely used, it has become common for numerous access points (APs) to overlap in a region, where most of those APs are managed individually without any coordinated control. This pattern of wireless LAN usage is called the private OBSS (Overlapping Basic Service Set) environment in this paper. Due to frame collisions across BSSs, each BSS in the private OBSS environment suffers severe performance degradation. This study approaches the problem from the perspective of congestion control rather than noise or collision resolution. The retry limit, one of the 802.11 attributes, could be used for traffic control in conjunction with TCP. Reducing the retry limit causes early discard of a frame, and it has a similar effect of random early drops at a router, well known in the research area of congestion control. It makes the shared link less crowded with frames, and then the benefit of fewer collisions surpasses the penalty of less strict error recovery. As a result, the network-wide performance improves and so does the performance of each BSS eventually. Reducing the retry limit also has positive effects of merging TCP ACKs and reducing HOL-like blocking time at the AP. Extensive experiments have validated the idea that in the OBSS environment, reducing the retry limit provides better performance, which is contrary to the common wisdom. Since our strategy is basically to sacrifice error recovery for congestion control, it could yield side-effects in an environment where the cost of error recovery is high. Therefore, to be useful in general network and traffic environments, adaptability is required. To prove the feasibility of the adaptive scheme, a simple method to dynamically adjust the value of the retry limit has been proposed. Experiments have shown that this approach could provide comparable performance in unfriendly environments.

• The Korean Journal of Air & Space Law and Policy
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• v.26 no.2
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• pp.69-100
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• 2011

The penalty clauses of 'Aviation Act' and 'Aviation Safety and Security Act' going into effect now were legislated because the aviation safety is being more influenced by the aviation safety system compared to the ground or maritime transportation and it is possible the aircraft can harm to people and wealth located in the ground as well as threaten the safety of the passengers and crew on board when it is the target of crimes. However, analyzing the current acts, applicable objects and behavioral requirements of some provisions are too general, and they are providing severely high penalties in many clauses without separating applicable objects and behavioral requirements. In addition, there are some critical legislative defects and there is a problem in terms of law-applicable area in the legal system. It is inferred that these legislative problems of the criminal special-law related to the aviation were caused by following reasons; first, aviation security experts or policy-makers than criminal law experts attended more actively in the enactment process, second, the communication among specialist groups were not accomplished well enough.

• Korean Security Journal
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• no.61
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• pp.333-352
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• 2019

In January and August 2019, there were amendments to the Unfair Competition and Trade Secrets Protection Act (UCPA) and the Industrial Technology Protection Act(ITPA). These amendments will contribute to technology protection. But these amendments need to be supplemented further. In the area of civil remedies, despite the introduction of treble damages in the case of the UCPA and ITPA, the provisions related to the submission of supporting data have not been maintained. Therefore, it is necessary to recognize the claim of the other party as true if it is maintained at the level of the revised Patent Act and the scope of submission of supporting data. And the enforcement of the case of compulsory submission for the calculation of damages, and the order of filing documents are not followed. ITPA, on the other hand, has introduced the compensation for damages, but there is no provision for estimating the amount of damages. Therefore, it is necessary to estimate the amount of lost profits, profits, and royalties. In the area of criminal remedies, both the UCPA and ITPA have raised the penalty, but the sentencing regulations are not maintained. In addition, although the recent outflow of technology has expanded beyond organizational deviations to organizational outflows, amendments need to be made in relation to the serious consequence for the punishment of related juristic persons, such as companies involved in it. It should be noted that Japan and the United States have corporate regulations and regulations. In addition, in relation to the confiscation system, Act on Regulation and Punishment of criminal proceeds concealment require that domestic defenses be confiscated by defense industry technology, while trade secrets and industrial technologies are confiscated only by "foreign" outflows, and an amendment is necessary.

• Korean Journal of Heritage: History & Science
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• v.34
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• pp.222-267
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• 2001

The purpose of this document is to explain the revisions of the Protection of Cultural Properties Act and its sub-laws which have been mad from Jan. 1999 to Sep. 2001. The Protection of Cultural Properties Act and its sub-laws have been revised three times from 1999 to 2001, before and after the Office of Cultural Properties was raised to Cultural Properties Administration on May 24, 1999. The main points of the revisions are as follows. First of all, the role of the local autonomous entities has been increased. The governor of the local autonomous entities is entitled to announce administrative orders related to the preservation of State-designated Cultural Properties. Also, the local autonomous entities has the authorities to examine whether the construction work which will be made in the outer boundaries, which is provided by regulations, of the protected area of the cultural properties might have any effect on preservation of cultural properties or not. Second, preventive actions to protect the cultural properties have been strengthened. If the scale of construction work is more than some scale, the preliminary survey of the surface of the earth to confirm the existence of buried cultural properties and their distribution is obligated. One who is promoting the development plan more than some scale must discuss the plan with the Administrator of Cultural Properties Administration in the process of planning. These actions would be effective to prevent the cultural properties from being damaged because of the development. Third, relaxation of the restrictions has been proceeded. On the basis of regulations which specify the actions to affect the preservation of cultural properties, negative system that does not limit the actions which are not specified in the regulations is introduced. The appropriateness of both protected structure and area should be regularly reviewed and adjusted. Also, most of the restrictions which was made only for administrative convenience and over-regulated the people's living have been revised. Finally, the number of cultural properties to be protected has been increased. Besides the State-designated Cultural Properties, the other cultural properties which are worthy to be protected as City-or-Province-designated Cultural Properties can be designated provisionally and protected. The system of registration and maintenance of the buildings and facilities which are not designated as the Modern Cultural Heritages is established. The penalty for damaging and stealing the cultural Properties which are not designated to be protected was strengthened. Even a dead natural monument can be acknowledged as an natural monument and it is limited to make a specimen or stuffing of the dead natural monument. All of these actions are fit to the high level of understanding of the public about the cultural properties and as the result of these actions, the number of cultural properties to be preserved has been increased. To sum up, the directions of revisions of the Protection of Cultural Properties Act and its sub­laws which have been made from Jan. 1999 to Sep. 2001. are the localization of the protection of the cultural properties, the strengthening of protective actions, the relaxation of various regulations and the increasing of the number fo the protected cultural properties. Also, various problems raised in the processes of implementations of the laws have been reviewed and revised.

• The Korean Journal of Air & Space Law and Policy
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• v.31 no.2
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• pp.145-176
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• 2016

Aviation safety can be secured through regulations and policies of various areas and thorough execution of them on the field. Recently, for aviation safety management Korea is making efforts to prevent aviation accidents by taking various measures: such as selecting and promoting major strategic goals for each sector; establishing National Aviation Safety Program, including the Second Basic Plan for Aviation Policy; and improving aviation related legislations. Obstacle limitation surface is to be established and publicly notified to ensure safe take-off and landing as well as aviation safety during the circling of aircraft around airports. This study intends to review current aviation obstacle management system which was designed to make sure that buildings and structures do not exceed the height of obstacle limitation surface and identify its operating problems based on my field experience. Also, in this study, I would like to propose ways to improve the system in legal and regulatory aspects. Nowadays, due to the request of residents in the vicinity of airports, discussions and studies on aviational review are being actively carried out. Also, related ordinance and specific procedures will be established soon. However, in addition to this, I would like to propose the ways to improve shortcomings of current system caused by the lack of regulations and legislations for obstacle management. In order to execute obstacle limitation surface regulation, there has to be limits on constructing new buildings, causing real restriction for the residents living in the vicinity of airports on exercising their property rights. In this sense, it is regarded as a sensitive issue since a number of related civil complaints are filed and swift but accurate decision making is required. According to Aviation Act, currently airport operators are handling this task under the cooperation with local governments. Thus, administrative activities of local governments that have the authority to give permits for installation of buildings and structures are critically important. The law requires to carry out precise surveying of vast area and to report the outcome to the government every five years. However, there can be many problems, such as changes in the number of obstacles due to the error in the survey, or failure to apply for consultation with local governments on the exercise of construction permission. However, there is neither standards for allowable errors, preventive measures, nor penalty for the violation of appropriate procedures. As such, only follow-up measures can be taken. Nevertheless, once construction of a building is completed violating the obstacle limitation surface, practically it is difficult to take any measures, including the elimination of the building, because the owner of the building would have been following legal process for the construction by getting permit from the government. In order to address this problem, I believe penalty provision for the violation of Aviation Act needs to be added. Also, it is required to apply the same standards of allowable error stipulated in Building Act to precise surveying in the aviation field. Hence, I would like to propose the ways to improve current system in an effective manner.

• The Korean Journal of Air & Space Law and Policy
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• v.35 no.2
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• pp.41-74
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• 2020

The monetary penalties system inherently has efficiency as DNA. In the event that administrative measures to recover unfair profits from businesses that violate the law, deprive business licenses, or order to suspend business, infringe the interests of ordinary consumers, a system that can achieve the same effect through financial sanctions. It is a monetary penalties. In addition, it is convenient for the government because it takes effect only by the administrative agency's unilateral imposition order compared to the trial process, which takes a long time and huge cost to prove the illegality. However, it is questionable whether procedural legitimacy is well established in Korea's aviation monetary penalties. Compared to foreign legislation, Korea's aviation monetary penalties system need to be improved. This paper was for the purpose of studying the improvement direction of the monetary penalties system disposed of in the Korean aviation field. This study suggests the direction by examining the US system, which is an aviation advanced country, in the aviation safety area. The research was conducted with the intention of exploring the direction as follows: First, the characteristics of the Federal Aviation Administration (FAA) aviation administrative sanctions and the US aviation penalty system will be outlined. Furthermore, with the recent paradigm shift in aviation safety management, this paper tried to look at new trends that focus on autonomous reporting of aviation safety as a proactive and preventive measure in conventional post-airline accident management administration, focusing on various systems including ASAP. This article also reviewed the formal process for imposing monetary penalties adopted by the FAA. Based on the above review, this paper also looked at ways to improve the reporting system for aviation safety in Korea.

• Journal of Legislation Research
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• no.53
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• pp.455-489
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• 2017

The new system on the Corporate Social Responsibility(CSR) in the Indian Companies Act became overnight sensation to the worldwide. However there has been very few studies which are analyzing a purpose of it under the context of Indian societies. This paper examines the circumstance whether the CSR activities is functioning well or not. And verifying problems regarding it and suggesting supportive measures are a target of this paper. Though Indian government already established CSR legislation, they did not stipulate the penalty clause. And that became why corporations were poorly perform on CSR activities in first year of enforcement. Furthermore, There is a proclivity that corporations lack an understanding for which activities could be recognized into the CSR. And they excused that they had no time for themselves to adjust an abruptly changing business landscape. With all, unlike rosy expectations, corporations only showed little interests to the area where the investment or attentions from the media are expected. Fortunately, incumbent legislative is fully aware of it and exploit their best resources to various social fields. Despite the doubts that they originally did not have any intention to introduce the penalty clause, they are handling problems in ways that corporations can be invited in public programs. They also need to request the service sectors to take a leading role of it, which could provide the financial, or telecommunication service to the people in rural province. Thus, the fact that there was a substantial rise in terms of the amount of CSR expenses in 2015 provides a supporting evidence to the endeavors of the government. In doing so, we could finally achieve a better understanding of two-fold goals shown in this paper; maturing settlement of this legislation and development of Indian society.

• Journal of the Society of Disaster Information
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• v.15 no.3
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• pp.440-449
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• 2019

Purpose: Fire-fighting organizations are the very first agencies that take actions at a disaster scene, and emergency rescue training is carried out for prompt and systematic response. However, there is a need for a change due to the limitations in emergency rescue trainings such as perfunctory trainings or trainings without considering regional or environmental characteristics. Method: This study is to conduct theoretical review with regard to emergency rescue training and present a measure to improve the emergency rescue training through attitude survey targeting fire-fighting organizations in Gangwon area. Result: Facilities that cause difficulties when doing emergency rescue activity were mostly hazardous material storage and processing facilities. In terms of the level of emergency rescue and response task, most respondents answered that the emergency rescue was insufficient. The respondents answered that the effectiveness of emergency rescue training was helpful, but some responses showed that the training was not helpful because of scenario-based training, seeming training, similar training carried out every year, unrealistic training, and lack of competent authorities' interest and perfunctory participations. Most respondents answered for the appropriateness of emergency rescue training and evaluation that they were satisfied, however, they were not satisfied with the evaluation methods irrelevant to the type of training, evaluation methods requiring unnecessary training scale, and evaluation methods leading perfunctory participations of competent authorities. Lastly, respondents mostly answered that training reflecting various damage situations are necessary regarding the demand on the improvement of emergency rescue training. Conclusion: The improvement measures for emergency rescue training are as follows. First, it is necessary to set and prepare various training contents in accordance with regional characteristics by reviewing major disasters occurred in the region. Second, it is necessary to revise the emergency rescue training guidelines and manuals for appropriate training plan for each fire station, provide education and training for working-level staff members, and establish training in a way that types, tactics, and strategies of emergency rescue training could be utilized practically. Third, it is necessary to prepare a scheme that can lead participation and provide incentive or penalty from the planning stage of training in order to increase the participation of supporting and competent authorities when an actual disaster occurs. Fourth, it is necessary to establish support arrangements and cooperative systems by authority through training by fire stations or zones in preparation for disaster situations that may occur simultaneously. Fifth, it is necessary to put emphasis on the training process rather than the result for emergency rescue training and evaluation, pay attention to the identification of supplement points for each disaster situation and make improvements. Especially, type or form of training should be considered rather than evaluating the execution status of detailed processes, and the evaluation measure that can consider the completeness (proficiency) of training and the status of role performance rather than the scale of training should be prepared. Sixth, type and method of training should be improved in accordance with the characteristics of each fire station by identifying the demand of working-level staff members for an efficient emergency rescue training.

• Korean Chemical Engineering Research
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• v.57 no.1
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• pp.51-57
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• 2019

A plant layout problem has a large impact on the overall construction cost of a plant. When determining a plant layout, various constraints associating with safety, environment, sufficient maintenance area, passages for workers, etc have to be considered together. In general plant layout problems, the main goal is to minimize the length of piping connecting equipments as satisfying various constraints. Since the process may suffer from the heat and friction loss, the piping length between equipments should be shorter. This problem can be represented by the mathematical formulation and the optimal solutions can be investigated by an optimization solver. General researches have overlooked many constraints such as maintenance spaces and safety distances between equipments. And, previous researches have tested benchmark processes. What the lack of general researches is that there is no realistic comparison. In this study, the plant layout of a real industrial C3MR (Propane precooling Mixed Refrigerant) process is studied. A MILP (Mixed Integer Linear Programming) including various constraints is developed. To avoid the violation of constraints, penalty functions are introduced. However, conventional optimization solvers handling the derivatives of an objective functions can not solve this problem due to the complexities of equations. Therefore, the PSO (Particle Swarm Optimization), which investigate an optimal solutions without differential equations, is selected to solve this problem. The results show that a proposed method contributes to saving the capital expenditures.