• Title/Summary/Keyword: CPA

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A Study on the Investigation and Analysis of Collisions at Sea (선박충돌사고의 원인조사 및 분석방법에 관한 연구)

  • 김상수;정재용;하원재;송두현;박진수
    • Journal of the Korean Institute of Navigation
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    • v.24 no.1
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    • pp.13-22
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    • 2000
  • The collisions at sea among marine casualties are not reduced as the tonnage and speed of ship's increase as well as the traffic quantity increase at sea, in spite of the improvement of nautical equipment, enforcement of crew's education and training as well as improvement of quality standard according to the implementation of ISM code. The measures to prevent the collisions at sea are simple, and are composed of six stage.: The first stage is that the officer on duty detect the target from his eye or radar information. The second stage is determining the type and kind of target-ship. The third stage is target tracking; calculation of target speed, course, CPA and TCPA from radar information or visual check. The fourth stage is determination of vessel in danger after calculation of third stage. The fifth stage is the judgement of situation if own ship is stand-on or give way vessel according to the 1972 COLREG. The last stage is to carry out proper action according to 1972 COLREG, under the circumstances. But by the case, the situations are so different under the different external conditions; for example, natural/navigational conditions, crew's human factors, ship's particular, rule or regulation, management system on board, the condition of watch keeping. Therefore the reasons and casualties are so complicated. This study aims to investigate the collision casualty at sea which needs to clarity all these causal factors of afore-mentioned, and to analyze the causes of problems so as to utilize them to establish the measures of preventing marine accidents. This study, described the concepts of causal factors into three groups; environmental factor, and company/on board management system and navigator's act. Also described how to investigate and analyzes the casual factors. Even though it was described in this paper how to detect the causal factors and reasons of collisions, and how to analyze the inter-relation of each causal factors, it is necessary to do further study how to analyze between the liability of concerned parties and the casual factors involved.

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An Improved Side Channel Attack Using Event Information of Subtraction (뺄셈연산의 이벤트 정보를 활용한 향상된 RSA-CRT 부채널분석공격 방법)

  • Park, Jong-Yeon;Han, Dong-Guk;Yi, Okyeon;Kim, Jung-Nyeo
    • KIPS Transactions on Computer and Communication Systems
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    • v.2 no.2
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    • pp.83-92
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    • 2013
  • RSA-CRT is a widely used algorithm that provides high performance implementation of the RSA-signature algorithm. Many previous studies on each operation step have been published to verify the physical leakages of RSA-CRT when used in smart devices. This paper proposes SAED (subtraction algorithm analysis on equidistant data), which extracts sensitive information using the event information of the subtraction operation in a reduction algorithm. SAED is an attack method that uses algorithm-dependent power signal changes. An adversary can extract a key using differential power analysis (DPA) of the subtraction operation. This paper indicates the theoretical rationality of SAED, and shows that its results are better than those of other methods. According to our experiments, only 256 power traces are sufficient to acquire one block of data. We verify that this method is more efficient than those proposed in previously published studies.

A Study on Ship Collision Avoidance Algorithm by COLREG (국제해상충돌예방규칙에 따른 충돌회피 알고리즘에 관한 연구)

  • Kim, Dong-Gyun;Jeong, Jung-Sik;Park, Gyei-Kark
    • Journal of the Korean Institute of Intelligent Systems
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    • v.21 no.3
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    • pp.290-295
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    • 2011
  • On the basis of DCPA(Distance to Closest Point of Approach) and TCPA(Time to CPA), the conventional algorithms for collision avoidances have a drawback that the '72 CORLEGs(International Regulations for Preventing Collisions at Sea, 1972) has not taken into account to prevent collisions between ships. In this paper, the proposed algorithm decides whether the own ship is a give-way vessel or a stand-on vessel by observing the relative bearing of the encountered ship. To determine the ship position and time for collision avoidance, the proposed algorithm utilizes the ellipse model for ship safety domain. The computer simulation is done to represent the process of adversive behavior. Using the proposed method, the past maritime accident is analyzed. The proposed method can be effectively applied to collision avoidance by CORLEGs even when the target ship's navigational lights is invisible in poor weather and/or in the restricted visibility.

Inhibitory Mechanism of Bromocriptine on Catecholamine Release Evoked by Cholinergic Stimulation and Membrane Depolarization from the Rat Adrenal Medulla

  • Lim, Dong-Yoon;Lee, Yong-Gyoon;Kim, Il-Hwan
    • Archives of Pharmacal Research
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    • v.25 no.4
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    • pp.511-521
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    • 2002
  • The purpose of this study was to determine whether bromocriptine affects the catecholamines (CA) secretion evoked in isolated perfused rat adrenal glands, by cholinergic stimulation, membrane depolarization and calcium mobilization, and to establish the mechanism of its action. The perfusion of bromocriptine ($1~10{\;}{\mu}M$) into an adrenal vein, for 60 min, produced relatively dose-dependent inhibition in the secretion of catecholamines (CA) evoked by acetylcholine (ACh, 5.32 mM), DMPP ($100{\;}{\mu}M$ for 2 min), McN-A-343 ($100{\;}{\mu}M$ for 2 min), cyclopiazonic acid (CPA, $10{\;}{\mu}M$ for 4 min) and Bay-K-8644 ($10{\;}{\mu}M$ for 4 min). High $K^+$ (56 mM)-evoked CA release was also inhibited, although not in a dose-dependent fashion. Also, in the presence of apomorphine ($100{\;}{\mu}M$), which is also known to be a selective $D_2$-agonist, the CA secretory responses evoked by ACh, high potassium, DMPP, McN-A-343, Bay-K-8644 and cyclopiazonic acid were also significantly depressed. However, in adrenal glands preloaded with bromocriptine ($3{\;}{\mu}M$) in the presence of metoclopramide ($15{\;}{\mu}M$), a selective $D_2$-antagonist, the CA secretory responses evoked by ACh, high potassium, DMPP, McN-A-343, Bay-K-8644 and cyclopiazonic acid considerably recovered as compared to that of bromocriptine only. Taken together, these results suggest that bromocriptine can inhibit the CA secretion evoked by stimulation of cholinergic receptors, as well as by membrane depolarization, in the perfused rat adrenal medulla. It is thought this inhibitory effect of bromocriptine may be mediated by inhibiting the influx of extracellular calcium and the release from intracellular calcium stores, through the activation of dopaminergic $D_2$-receptors located in the rat adrenomedullary chromaffin cells. Furthermore, these findings also suggest that the dopaminergic $D_2$-receptors may play an important role in regulating adrenomedullary CA secretion.

A Comparative Analysis on the Characteristics of ODI by Korean and Japanese Firms into Asian Continent (한국·일본의 대 아시아지역 직접투자 특성의 비교분석)

  • Kim, Seong Ki;Chae, Doo Byung;Kang, Han Gyoun
    • International Area Studies Review
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    • v.14 no.3
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    • pp.267-289
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    • 2010
  • The purpose of this paper is to compare the different characteristics of Korean and Japanese Overseas Direct Investment(ODI) in Asia. An empirical test consists of two parts, the determinants of ODI and the micro characteristics of subsidiaries in Asia between Korea and Japan. Multiple regression and logistic regression model are used in empirical tests as methodology. The coefficient of GDP is significant and positive sign to sole venture in both countries. The coefficient of CPA in Korea is significant and positive sign to joint venture but insignificant in Japan. The coefficient of WAGE in Korea is significant and positive sign to joint venture but is significant and negative sign to joint venture in Japan. The coefficient of LBIT is significant and positive sign to joint venture in Japan. The coefficient of HOME is significant and positive sign to sole venture in both countries.

Effects of Black rice (Oryza sativa L.) Aleurone layer on Cyclophosphamide-induced Immunosuppression in Mice (Cyclophosphamide에 의해 유도된 면역 저하 마우스에서 흑미 (Oryza sativa L.) 호분층의 면역 활성 효과)

  • Lee, Eun Byeol;Choi, Ji-Hye;Kim, Si Hyun;Jang, Hwan Hee;Lee, Sung Hyen
    • Korean Journal of Pharmacognosy
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    • v.52 no.3
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    • pp.170-176
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    • 2021
  • Anthocyanins are considered as one of the major functional components including cyanidin-3-glucoside and peonidin-3-glucoside anthocyanins of black rice (Oryza sativa L., BR) aleurone layer (OAL) extract. The immunomodulatory biological effects of OAL has rarely been evaluated. This study has extensively studied the immunomodulatory effects of BR in immunosuppressed mice by CPA. The immunostimulatory effects of BR extract in in vivo at 150 (OAL-1) and 300 mg/kg body weight (OAL-2) for OAL groups were measured and compared to the normal group (CON) ingested with distilled water only or other groups. After the 14 days of oral administration, immune related organ weights, serum immunoglobulin (Ig) A and IgG, and cytokines (IL-12, TNF-α) levels, splenocytes proliferation rate, and NK cell activity were evaluated as immune related biomarkers. The serum IgA and IgG values in the OAL-treated groups increased to the level of the CON. OAL significantly and effectively controlled the IL-12 and TNF-α levels and NK activity compared to the negative control (NC) group. The results suggest that BR aleurone layer with immunomodulatory activities has a great potential as a functional food by itself or as a supplement.

Analysis on the Importance and Competitiveness of Support Services of the Food Service Franchise Headquarters AHP Technique (AHP를 이용한 외식프랜차이즈 가맹본부의 지원서비스의 중요도 및 경쟁력 분석)

  • CHOI, Chaebong;LEE, Sang-Suk
    • The Korean Journal of Franchise Management
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    • v.10 no.4
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    • pp.7-18
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    • 2019
  • Purpose: This study identifies the relative importance of the sub - factors of initial services and continuous services using AHP (Analytic Hierarchy Process) method, and calculates the competitive index for the detailed factors. The purpose of this paper is to propose the establishment of long - term and short - term management strategy for expansion of business of food service franchise, franchisors, long - term and win - win relationship with franchisees, and rationalization of operating system. Research design, data, and methodology: The population for the survey is 92 franchisees in 46 foreign brands and 46 domestic brands in the Seoul metropolitan area (Seoul / Gyeonggi / Incheon). The survey was conducted from July 1 to August 31, 2018 through the survey agency with a telephone interview and a surveyor's direct visit. A total of 100 questionnaires were collected, but a total of 92 parts were used for analysis except 8 parts that were considered to contain false information. Using the AHP method, relative importance and competitiveness index were calculated for the details of initial services and continuous services. Results: The results shows continuous services were significantly higher for both foreign brand franchises, domestic brand franchises, and overall than initial services, This suggests that the continuous services of the affiliated franchisors has a higher relative importance than the initial services. Among the continuous services, brand reinforcement and promotion were significantly higher for both foreign brand merchants and domestic brand franchises. This can be regarded as the most important factor in brand reinforcement and promotion when selecting a food service franchisors. Conclusions: In the Standard Terms and Conditions governed by the Fair Trade Commission, the franchisors should increase the fairness by creating manuals for supporting services, especially after opening, and regularly checking whether the supporting services have been carried out like manuals since the establishment of franchisees. In addition, the Brand Strengthening and Public Relations Committee (tentative name) jointly participated by the franchisors and franchisees for the purpose of strengthening and promoting the brand, suggesting a system for transparent and efficient execution of the brand reinforcement and promotion budget and monitoring afterwards.

Design of High Efficiency Transmission Dielectric Grating for Chirped Pulse Amplification (CPA 시스템 구성을 위한 고효율 투과형 유전체 회절격자 설계)

  • Cho, Hyun-Ju;Jung, Jae-Woo;Lee, Sang-Hyun;Kim, Soojong;Lee, Jeongseop;Jin, Daehyun;Jung, Jiho;Son, Seonghyun
    • Korean Journal of Optics and Photonics
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    • v.33 no.6
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    • pp.260-266
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    • 2022
  • A diffraction grating structure composed of two matching layers and two grating layers was formed, and a diffraction grating with high transmission diffraction efficiency in the -1st order was designed through an optimization technique. The designed diffraction grating had a transverse electric wave diffraction efficiency of 99.997% at the design center wavelength, and had a wavelength width of 80 nm and an incident angle width of 20.0° that maintained a diffraction efficiency of 95% or more. By performing the grating tolerance analysis, it was confirmed that the thickness tolerance for a diffraction efficiency of 95% or more was secured to at least 60 nm, and the diffraction efficiency could be maintained even in a trapezoidal shape with an internal angle of less than 10°.

The Conversion method from ID-based Encryption to ID-based Dynamic Threshold Encryption (ID기반 암호시스템을 이용하여 ID기반 동적 임계 암호시스템으로 변환하는 방법)

  • Kim, Mi-Lyoung;Kim, Hyo-Seung;Son, Young-Dong;Lee, Dong-Hoon
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.22 no.4
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    • pp.733-744
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    • 2012
  • Dynamic threshold public-key encryption provides dynamic setting of the group of all users, receivers and the threshold value. Over recent years, there are many studies on the construction of scheme, called ID-based dynamic threshold encryption, which combines the ID-based encryption with dynamic threshold encryption. In this paper, we analyze the ID-based dynamic threshold encryption proposed by Xing and Xu in 2011, and show that their scheme has a structural problem. We propose a conversion method from ID-based encryption which uses the bilinear map to ID-based dynamic threshold encryption. Additionally, we prove this converted scheme has CPA security under the full model.

Effects of Aged Platycodon grandiflorum on Cyclophosphamide-induced Immunosuppression in Mice (홍도라지 추출물이 마우스 모델에서 Cyclophosphamide에 의한 면역력 저하 억제에 미치는 영향)

  • Lee, Eun Byeol;Choi, Ji-Hye;Jang, Hwan-Hee;Hong, Ha-Cheol;Lee, Hae-Jeung;Jeong, Hyun Cheol;Lee, Sung-Jin;Lee, Sung Hyen
    • Korean Journal of Pharmacognosy
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    • v.51 no.4
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    • pp.340-348
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    • 2020
  • This study was conducted to evaluate the immunomodulatory effects of red doraji (Platycodon grandiflorum, RD) prepared by repeated steaming and drying process in the immune-suppressed mice induced by pre (RD-A) or post-treatment (RD-B) with cyclophosphamide. The immune-stimulating effects of ethanol RD extract in in vivo at 150 (RD-1) and 300 mg/kg body weight (RD-2) for RD-A and RD-B groups were measured and compared to the NC group supplied with distilled water only or positive control group. After 14 days of oral supplement, serum IgA, IgG, and cytokine levels, splenocytes proliferation rate, NK cell activity, and gene expression of cytokines were measured as immune related biomarkers. Serum IgA, IgG, IL-1β, and IL-12 levels increased in both RD-A and RD-B groups while serum TNF-α level decreased in RD-A group compared to the NC group. Splenocytes proliferation rate, NK cell activity, and cytokine (IL-1β, IL-6, IFN-γ) expression levels were also improved by RD supplement in the both groups. The RD showed more significant immunomodulatory effects at higher dose (RD-2) rather than the lower dose (RD-1). Thus, RD has an immune efficacy in a dose dependent manner and can be used as an immune stimulating source to improve immunity.