• The Journal of Korean Institute of Communications and Information Sciences
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• v.24 no.10B
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• pp.1852-1860
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• 1999

This paper studied performance of the AAL2 for variable rate real time services in ATM network with discrete-time simulation model. In this simulation, input parameters are packet fill delay for AAL2 PDU generation, guard time for ATM cell generation, burstness and number of channels. Though variation of the above mentioned parameters, we obtained end-to end delay variations and throughput, analyzed performance effect of the each parameter for voice packet service.

• Convergence Security Journal
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• v.13 no.2
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• pp.67-73
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• 2013

This research is to define the Aesthetics of Karatedo as Security Guard Martial Art by explore the aesthetics of Karatedo being invigorated as security guard martial art. The first one is beauty of space. The offense and defense of Karatedo as Security Guard Martial art are to fill in, to come out and to move from side to side. It help to have higher judgment. Secondly, it is beauty of time. It is subjective time felt by people training Karatedo. The third on is beauty of unity. We can see formal beauty of unity such as white dogi or black suit of security guard and dynamic beauty of unity such as quick and slow, strong and soft or movement of hand and foot. The forth one is beauty of symmetry. It can be shown strongly by triangle or moving of team kata and triangle between athletes and referee at Kumite competition. The fifth one is beauty of balance. It can by shown well by continual Karatedo kick motion, jumping kick motion at Kumite, jumping motion, quick turning, or moving such as standing on one foot at kata. The sixth one is beauty of harmony. The whith Dogi and blue or red guard at Kumite competition shows harmony of yin and yang and we can see also various harmony such as strong and soft, quick and slow, or high and low at Kata competition. The seventh one is beauty of curve. We can see beauty of straight line and curve by watching line of hand and foot from starting point to ending point. Specially, moving line of white dogi shows strongly beauty. The eighth one is beauty of rhythm. The rhythm is specified in Kumite kata competition rules. It is also shown by basic step, left and right step, various moving of foot, continual offense of hand or continual rhythm of offense and defense. The last one is bezuty of ethics. It is manner, duty as human, and moderation being important in Karatedo.

• Journal of the Korean Society of Marine Environment & Safety
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• v.19 no.4
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• pp.352-358
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• 2013

The objective of this paper is to introduce on a mobile APP called MAMIS(Marine pollution Accident response Mobile Information System) and it's functions. MAMIS was developed by Korea Coast Guard for marine pollution responder in 2012. Users can get information on marine pollution response easily without being restricted by time and place. MAMIS can be operated by smart phones with Android OS and iOS, both of which are the most popular mobile operating systems in Korea. And it has been developed in the form of hybrid APP which combined the functions of mobile APP and mobile WEB. MAMIS is composed of 9 menus, 5 mobile-based ones and 4 web-based ones. The mobile-based menus are on substance information, clean-up skills, response measures, QR code scanning, and volunteer's safety, and the web-based ones on weather information, response equipment, clean-up materials, and SNS.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.5A
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• pp.417-425
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• 2007

While the cyclic prefix lengths of downlink OFDMA(Orthogonal Frequency Division Multiple Access) systems are determined based on the maximum delay spreads encountered in cellular environments, the guard interval of uplink OFDMA systems should consider the timing offsets of uplink signals as well as the delay spread lengths. Especially in the cases of initial accesses, handovers, and considerable time elapsed without data transmissions between base and mobile stations in a large cell, uplink timing offsets can be large and a very long guard interval length may be required. In order to keep the small size of the cyclic prefix in uplink OFDMA systems, the systems require a method of extending the guard intervals for users with large timing offsets without affecting the cyclic prefix length of the system. This paper proposes a method extending the guard intervals of individual users in uplink OFDMA systems.

• Journal of Advanced Navigation Technology
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• v.16 no.5
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• pp.794-800
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• 2012

In this paper, we propose a scheme for improving not only the utilization of frequency bands in the guard channel scheme but also the dropping rate of cognitive radio user in the wireless cognitive radio-based cellular network. The proposed scheme enables cognitive radio users to utilize the guard channel for servicing only handoff calls in normal times, but cognitive radio users must vacate the frequency channel when handoff call appearing. At this time our scheme ensures their seamless services for cognitive radio users, by predicting handoff call's appearance by MMOSPRED (Multi-Media One Step Prediction) method and then reserving the demanded channels for spectrum handoff calls. Our simulations show that our scheme performs better than other schemes; GCS(Guard Channel Scheme) and a scheme without prediction in terms of cognitive users call's dropping rate and resource utilization efficiency.

• Korean Security Journal
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• no.36
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• pp.139-176
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• 2013

It is believed that the Koryo dynasty era is the period which has very special meaning with regard to the history of the VIP guard system. The guard system in the early Koryo dynasty time focused on the official protection for kings and their families with absolute royal authority. On the contrary, the guard system in the late Koryo dynasty time, especially military regime period, conducted providing private protection for military rulers and increasing their power. The official guard troops named 2Gun6Wii became just perfunctory organizations at that time. That is the reason why this study develops the discussion only about the guard system of the early Koryo time. The official VIP guard organizations under the government structure of the early Koryo period were Naegoonbu, Byeongbu and Joongchoowon. This study particularly reviewed the Joongchoowon with thorough research. In the meantime, the guard organizations under the military chart of the early Koryo period were 2Gun6Wii, Gonghakgoon, Geonryonggun and so on. 2Gun consisted of ungyanggun and yonghogun. They were the royal bodyguards. This study especially tried to review the substance of the Gonghakgoon, Geonryonggun with different point of view from other theories. The Gumowwii, one of 6 Wii, conducted many official duties such as royal palace protection, capital city Gaesung defence, area patrols, criminal apprehension and disturbance prevention. It also accomplished crowd control and convoy mission at the streets to respond emergency cases while carrying out VIP protection roles for kings and Chinese diplomats. Many bibliographies verified that the Chunwoowii was the royal bodyguards which helped kings during state ceremonies and grand meetings held by kings. Consequentially, it is true that this study discovered, analyzed and evaluated various references and research materials related with the guard system. It is meaningful that this study newly reviewed the organizations and functions of the guard system as one structure.

• Korean Security Journal
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• no.16
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• pp.357-371
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• 2008

Currently, the security operations in nation's key foundations in Korea are performed by private police and special security guard in accordance with the Private Police Act and Security Business Act, respectively. In 1960s, The Korean Government introduced the private police system in terms of the national security issues, but it was just a hurriedly-set plan on the basis of Japanese Sunsa system as by that time there was no such system revitalized. However, the special security guards could offer wider range of security services including those of the private police with the enactment and revision of the Security Business Act 1976 and April 2001, respectively. Moreover, the expectations and interests rose over the special security guards in nation's key foundations after 9.11Terror Event in the U. S. 2001. However, as we investigated the current education/training system for the special security guard, we found that such education/training which is not activating the specialty of special security guard will not respond to the social demands. Special security guard owns its own characteristics other than those of general security guard as they are in service in nation's key foundations. Thus, the effcient management and training for the special security guard is the most important matter for the safety and security of nation's key foundations. Therefore, the well-educated special security guard through the reorganized and specialized education/training for the protection of nation's key foundations is expected to offer qualitatively improved security services.

• Korean Security Journal
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• no.2
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• pp.259-289
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• 1999

The Security Industry has dynamic working conditions. So this study intends to find the advisable direction for the reduction of accidents. To achieve the aim, the investigation of documents and the examinations of actual proofs have been done to figure the theoretical background and to see the basic knowledge of security industry. The questionnaire was composed of two question sheets to search real data and actual proofs, with making targets of pure security organization and personnel. The one consists of 9 questions to find the scale and extent of security organizations and the population and character of security personnel, and the other 25 questions in 3 major areas to analyze the causes, the frequency rates, the factors, and the condition of accidents. The period of survey was July 15th to October 15th in 1997 by mail/telephone/interview. The questionnaires were efficiently returned from 102 different organizations including the public security groups of Seoul Metropolitan Police Bureau and so on, with the information of 8,222 persons having worked for Korean Security Industry in 1996. So being based on the reality, some meaningful facts were found, and were compared with the national statistics of the Government. This study is made up of 5 chapters : in the 1st chapter the motivation, the object, the method, the direction and the limitation of the approach were presented ,in the 2nd chapter the theoretical background were inferred ; in the 3rd chapter the collected data of accidents in Korean Security Industry were analyzed and explained on the base of the questionnaires , in the 4th chapter the advisable facts connected with preventing accidents were mentioned ; in the last the conclusion were stated. With the replies of 102 different organizations including the information of 8,222 persons in 1996, the main facts found or analyzed through this study are as follows. Firstly, accident is an unpredictable and occasional event. It occurs to man and/or thing, but the frequency rate of accidents in Korean Government and other Institutes has been calculated and evaluated only in the point of the accident related with man. Secondly, the factors of accidents are firstly relevant to the way preventing accidents in Security Industry in Korea. However the frequency rate is academically calculated and evaluated by at once man(population) and hour(time). But the Government has done the rate only by man(population). This can be improper and inaccurate rates. Thirdly, the confused concept of security is used in Korean Government, academic society, corporation and so on. Therefore the detailed formation of the concept is needed for the development of Security Industry in Korea. Fourthly, security organizations can be classified into 'public security(public law enforcement)' and 'private security' according to its identification, and furthermore 'private security' can be divided into 'facilities-guard service', 'body-guard service', and 'patrol service' according to its major role. Fifthly, in the viewpoint of the number of both organization and population,'facilities-guard service' is centered in Korean 'private security'. According to the analyzed results of the questionnaires in this study, the frequency rate of accidents of Korean Security Industry is 0.43(%) totally in 1996 : 'facilities-guard service' 0.54(%), 'body-guard service' 0.12(%), and 'patrol service' 0.21(%) in 'private security', and 'public security' 0.20(%). With regard to the accident frequency rate of organization and population, 'facilities-guard service' is the highest. The accident frequency rate of population in 'facilities-guard service' organization ranges dispersively from 0.20(%) to 11.11(%). Sixthly, the accidented rate of workers having serviced for under one year is 57.6(%). This can mean that the main factor of accidents in Korean Security Industry is the lack of role-understanding and training/education. And another factor can be found on the time of accident occurrence. Many accidents have been occurred on the relaxed points like as just after lunch and morning rush-hour. Lastly, the major advisable facts related to preventing accidents are as follows : The workers who are over fifty years old in 'facilities-guard service' organization need to be educated for preventing accidents ; It is desirable that the training and education to prevent accidents should be practiced in the time of pre-service ; As the style of accidents and the age of the accidented are not same according to major service area('public security' and 'private security' : 'facilities-guard service', 'body-guard service', and 'patrol service'), the plans to prevent accidents must be different and various. However fracture and bruise are general accidents in Korean Security Industry ; Workers must care about traffic accident and violent fall ; It seems that the grouped working with other two persons will reduce accident occurrence possibility rather than individually single working.

• Journal of Navigation and Port Research
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• v.38 no.1
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• pp.53-57
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• 2014

This thesis, concentrates on marine collision risks of the area divided by cells. Using a gas molecular collision calculation model, a collision risk model is proposed. Collision risk is estimated by relative angle, relative speed, and ship's density in the cell. For one week, Automatic Identification System (AIS) data was collected and analyzed on the Busan North Port area. The results indicate a high-risk area at the sea route connection point in Busan North Port. It also shows that twilight is the time of day when most collisions occur. This means that the area is high risk due to the number of collisions and other dangerous factors related to twilight. Although there is still need to consider other risks such as grounding risks, the results of this study are useful to for plotting a risk map for the port.

• Journal of the Korea Institute of Military Science and Technology
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• v.19 no.1
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• pp.50-56
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• 2016

This paper is about the implementation of the OFDM-based border guard/reconnaissance communication terminal systems. We have implemented Real-time Dynamic DL/UL symbol rate control function using the DL-MAP message, and proposed error detection method caused by malfunctioning and timing optimization method. The proposed scheme detects the variable rate symbol decoding timing without increasing additional physical layer logic, and also provides a wide variety of DL/UL data transfer rate. Furthermore, the proposed scheme applies to the current border guard/reconnaissance equipment and confirms a operation performance through field tests and demonstration at home and abroad.