• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.12A
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• pp.1153-1160
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• 2005

OFDM/OQAM(Offset QAM)-IOTA system requires the IOTA(Isotropic Orthogonal Transform Algorithm) function that has superior localization property in time and frequency domain instead of guard interval used for conventional OFDM/QAM system to be robust to multipath channel. Therefore, OFDM/OQAM-IOTA system has more spectral efficiency than conventional OFDM/QAM system. But, when channel estimation scheme for conventional OFDM/QAM system is applied straightforwardly to OFDM/OQAM-IOTA system, an intrinsic Inter- symbol-Interference is observed. So suitable preamble structure for the channel estimation scheme of OFDM/OQAM-IOTA system is required. In this paper, we propose a new preamble structure that is appropriate to OPDM/OQAM-IOTA system and then perform ideal channel estimation and practical channel estimation in low-to-medium mobile speed and compare them with conventional OFDM/QAM system. Simulation results show that OFDM/OQAM-IOTA system with proposed preamble structure has 1.5 dB Eb/NO gain on Target BER $10^{-3}$ and about $25\%$ transmission rate gain against the conventional OFDM/QAM system considering quarter of FFT size as guard interval size.

• Journal of the Korean Society of Marine Environment & Safety
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• v.9 no.1
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• pp.79-87
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• 2003

To improve the educational system of Korea Maritime Police Agency(KMPA), the authors investigate and evaluate the present course and curricula in details comparing with the systems of US Coast Guard and Japanese Coast Guard As a result, it is suggested that KMPA try to recruit good-quality officers through the diverse route, develop the future-oriented educational, system, adjust the course and curricula to meet KMPA's role and mission for 21st century. Besides, it requires that KMPA establishes its own institute to carry out the recruit training and re-freshening courses for both the officers and enlisted person.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.2 no.1
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• pp.59-70
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• 1998

In the wireless mobile exchange communication system, the proper handling of originating call(OC) and handover call(HC) is important. Specially, when it's viewed from the user side, mobile users feel more weighting soul disappointment with the handover blocking probability moving from current cell to adacent cell than with originating call blocking probability happening new call in current cell. Accordingly,this paper is proposed and analyzed the timeout buffer system and guard channel for decreasing handover blocking probability. In analytic result, The more guard channel increase,t he more originating call blocking probability increase and handover blocking probability decrease. Also, the more timeout duration increase, the more handover blocking probability decrease.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.10 no.3
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• pp.75-82
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• 2010

Korea has made a plan to allocate CH 14~CH 51 (470 MHz~698 MHz) for DTV. This paper assumes that DTV operates on CH 51 (692 MHz~698 MHz) and CDMA system operates on CH 52 (698 MHz~704 MHz) in spare band. Minimum Coupling Loss (MCL) method to get protection distance and Spectrum Engineering Advanced Monte Carlo Analysis Tool (SEAMCAT) to get guard band through 5 % interference probability are used. The protection distance is required to be 665.67 km at close frequency offset of 698.625 MHz between DTV transmitter and CDMA Base Station (BS) receiver. The required guard band between DTV transmitter and CDMA Mobile Station (MS) receiver is 5 MHz for the worst case of rural environment. There is no serious impact between CDMA MS transmitter and DTV receiver. The required guard band between CDMA BS transmitter and DTV receiver is 6.25 MHz for the worst case of urban environment. The analysis results may offer a reference and be helpful for considering interference between DTV and other communication systems.

• Journal of the Korea Society for Simulation
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• v.31 no.2
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• pp.11-20
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• 2022

There is a critical need for AI assistance in guard operations of Army base perimeters, which is exacerbated by changes in the national defense and security environment such as force reduction. In addition, the possibility for human error inherent to perimeter guard operations attests to the need for an innovative revamp of current systems. The purpose of this study is to propose a real-time object detection AI tailored to military CCTV surveillance with three unique characteristics. First, training data suitable for situations in which relatively small objects must be recognized is used due to the characteristics of military CCTV. Second, we utilize a data augmentation algorithm suited for military context applied in the data preparation step. Third, a noise reduction algorithm is applied to account for military-specific situations, such as camouflaged targets and unfavorable weather conditions. The proposed system has been field-tested in a real-world setting, and its performance has been verified.

• Journal of the Korean Society of Marine Environment & Safety
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• v.29 no.1
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• pp.15-23
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• 2023

Through the revision of the Framework Act on Administrative Regulations (July 17, 2019), the government minimized regulations and applied the comprehensive negative regulation principle to enhance economic vitality. However, a legally mandatory certification system has been applied to marine pollution prevention materials and chemicals, and inspection is conducted every time a product is sold, suppressing the autonomy of manufacturers. In addition, the majority of manufacturers of marine pollution prevention materials and chemicals are small businesses; therefore, they take the approach of producing small quantities of products whenever a buyer requests an order. Consequently, the need for deregulation was raised to ensure autonomy of the market and industry, and improve efficiency in accordance with the current trend of approval, performance test, and inspection systems for marine pollution prevention materials and chemicals. In this study, problems within the current system were identified and improvement plans are proposed through comparison and analysis of domestic and foreign systems.

• Korean Security Journal
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• no.18
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• pp.143-167
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• 2009

As of entering the 21st century, a trend in the field of a private security industry among the advanced countries have been increased a qualification system and train session to meet the needs of professionalism. Intensifying the professionalism in Korea, education and train system has been initiated to change but the oligopoly market already formulated due to impractical selection standard and management of education system. Issuing certification and offering basic training through a designated institution for the purpose of improving quality of the private security industry worker, its practical effectiveness were lower than expectation. Rather certification-holder or security agency, institution or truster's rent-seeking behavior have been increased by occupational licensing system. The founded results, which were associated to problems in selecting and educating to the private security guard, in this study were that any verification has been initiated towards dual-system in official approval and structural problems in education system, and non-existence of verification for professionalism and management capability to security agency owner and its upper managerial level. Current a dual system in an officially authorized verification system and completion of security guard credential requested change to an unified official qualification verification system to solve those problems. Ranges of an applicant to the unified official qualification verification system should be extend to the whole population in the private security industry. Moreover, minimization of the dead-weigh loss, which is caused by oligopoly phenomenon while using its market-dominant status, increasement number of designated institution, which allows self-regulating competition, and endowment of autonomy, which is in selecting education and agency, were requested to solve the problems in selecting and educating to the private security guard. In order to minimize stated problems while maintaining objectiveness, a new manage and supervise institution, which is called a 'private security industry committee', should be establish. The private security industry committee is a formation of governance network which are participated from professional group to civil organization.

• Journal of the Korean Society of Marine Environment & Safety
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• v.26 no.3
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• pp.227-232
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• 2020

This paper develops a risk index based on an indicator of risk assessment in terms of coastal activity location and accident type. The risk index is derived from a formula which adds the consequence of failure to a vulnerability value, then subtracts the mitigation value. Specifically, the consequence of failure is the number of casualties in coastal activity locations. An indicator of vulnerability refers to coastal environment elements and social elements. A pointer of mitigation includes managerial and organizational elements that indicate the capabilities of coastal activities. A risk rating of coastal activity location is found from a risk matrix consisting of the accident location and type. The purpose of this study is to prevent accidents at coastal activity locations by allowing the Coastal police guard to monitor effectively and inform visitors of potential risks.

• Journal of Korean Society for Quality Management
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• v.41 no.4
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• pp.673-681
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• 2013

Purpose: The purpose of this study is to investigate the design optimization modeling of screening procedures based on the assessment of misclassification errors. Methods: Misclassification errors due to measurement variability are derived for normally distributed quality characteristics. Further, an optimization model for ensuring the level of outgoing quality is proposed and demonstrated through an illustrative example. Results: It is shown that two types of misclassification errors (i.e., false acceptance and false rejection) may be properly compromised through an analytical assessment of measurement errors and an optimization modeling. It is also discussed that a variety of optimization modeling may be enabled based on the derivation of measurement errors. Conclusion: It may be concluded that the design of screening inspection may further be facilitated by including the effect of measurement errors on the performance of screening inspection procedure.

• Journal of the Korean Society of Costume
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• v.28
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• pp.19-30
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• 1996

This study investigate through the Balin-banchado in the Kookjangdogameuigue how the system of banchado ceremony exchanged during the middle late the Yi dynasty and in the period of introducing Wastern civilization The Balinbanchado is carry a coffin out of the house to the royal mausoleum. The characteristic in the general strucutre share banchado with rites of introduction rites of center and rites of finishing. Balin-banchado varies according to the objects and the times of a state funeral. In comparsion with Karaebanchado there are investigate the general structure cer-emonial arms and ceremonial costumes. The special feature of two banchado varies rites of center among rites of three. in the ceremonial arms aspect the characteristic of two ban-chado differ from the objects and the times. In the ceremonial costumes the peculiarity of two banchado can be divided into the guard costumes and the ceremonial arm costumes. The most formal attire of the guard costumes. were murning dress and yang-kwan-chobok and samo-danryeong In the ceremonial arm costumes the most outstanding was hongkun-hongeui baik-kun-baikeui in two banchado.