• Title/Summary/Keyword: Chosun University

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Influence of Cilnidipine on Catecholamine Release Evoked by Cholinergic Stimulation and Membrane Depolarization in the Perfused Rat Adrenal Gland

  • Lim, Dong-Yoon;Woo, Seong-Chang;Ko, Suk-Tai
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 2001.11a
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    • pp.95-95
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    • 2001
  • Ciinidipine (FRC-8635) is a newly synthesized novel DHP type of organic Ca$\_$2+/channel blockers that have been developed so far in Japan (Yoshimoto et al., 1991 : Hosono et at., 1992). It also has a blocking action on L-type voltage-dependent Ca$\^$2+/channel (VDCCs) in the rabbit basilar artery (Oike et al., 1990) and a slow-onset and long-lasting hypotensive action in clinical and experimental studies (Ikeda et al., 1992 ; Tominaga et al., 1997). Recent electrophysiological data indicate that cilnidipine might be a dual-channel antagonist for peripheral neuronal N-type and vascular L-type Ca$\^$2+/channels (Oike et al., 1990 ; Fujii et al., 1997; Uneyama et at., 1997). However, little is known about the involvement of N-type VDCCs in contributing to the muscarinic receptor-mediated CA secretion. Therefore, the present study was attempted to investigate the effect of cilinidipine on secretion of catecholamines (CA) evoked by ACh, high K$\^$+/, DMPP and McN-A-343 from the isolated perfused rat adrenal gland. Cilnidipine (1-10 ${\mu}$M) perfused into an adrenal vein for 60 min produced dose- and time-dependent inhibition in CA secretory responses evoked by ACh (5.32${\times}$10$\^$-3/M), DMPP (10$\^$-4/ M for 2 min) and McN-A-343 (10$\^$-4/ M for 2 min). However, lower dose of lobeline did not affect CA secretion by high K$\^$+/(5.6${\times}$10$\^$-2/ M), higher dose of it reduced greatly CA secretion of high K$\^$+/. Cilnidipine itself did also fail to affect basal catecholamine output. Furthermore, in adrenal glands loaded with cilnidipine (10 ${\mu}$M), CA secretory response evoked by Bay-K-8644 (10 ${\mu}$M), an activator of L-type Ca$\^$2+/channels was markedly inhibited while CA secretion by cyclopiazonic acid (10 ${\mu}$M), an inhibitor of cytoplasmic Ca$\^$2+/-ATPase was no affected. Moreover, $\omega$-conotoxin GVIA (1 ${\mu}$M), given into the adrenal gland for 60 min, also inhibited time-dependently CA secretory responses evoked by ACh and high K$\^$+/.

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A Pulse-Echo Testing Model for Partially Damaged Ultrasonic Transducers (부분 손상을 입은 초음파 탐촉자의 펄스-에코 시험 모델)

  • Song, Sung-Jin
    • Journal of the Korean Society for Nondestructive Testing
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    • v.16 no.2
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    • pp.95-108
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    • 1996
  • In ultrasonic testing, flaw signal from which quantitative information on flaws is determined is influenced by 3 factors : (1) the incident wavefield.produced by the transducer, (2) the scattered waves produced by flaws, and (3) the reception of the scattered waves back at the transducer. So even small changes in transducer performance due to aging or unexpected damages can produce the changes in the characteristics of flaw signal and finally the changes in the quantitative information on flaws. Thus a reliable calibration method of transducer performance is desired. Recently, theoretical models for ultrasonic testing have been employed as reference standards for the calibration of transducers which are considered as circular planar piston sources in the most of cases. But this simplification cannot be applied to partially damaged transducer which has lost their symmetry in performance, even not in appearance. Unfortunately there has been no reliable practical model which can be used for the calibration of partially damaged transducers. Here a pulse-echo testing model for partially damaged ultrasonic transducers was developed with experimental verification. The experimental responses agree very well with the theoretical prediction. So we expect that this model can be served as a theoretical reference standards for transducer calibration.

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An Embedded System Design of Collusion Attack Prevention for Multimedia Content Protection on Ubiquitous Network Environment (유비쿼터스 네트워크 환경의 멀티미디어 콘텐츠 보호를 위한 공모공격 방지 임베디드 시스템 설계)

  • Rhee, Kang-Hyeon
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.47 no.1
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    • pp.15-21
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    • 2010
  • This paper proposes the multimedia fingerprinting code insertion algorithm when video content is distributed in P2P environment, and designs the collusion codebook SRP(Small RISC Processor) embedded system for the collusion attack prevention. In the implemented system, it is detecting the fingerprinting code inserted in the video content of the client user in which it requests an upload to the web server and in which if it is certified content then transmitted to the streaming server then the implemented system allowed to distribute in P2P network. On the contrary, if it detects the collusion code, than the implemented system blocks to transmit the video content to the streaming server and discontinues to distribute in P2P network. And also it traces the colluders who generate the collusion code and participates in the collusion attack. The collusion code of the averaging attack is generated with 10% of BIBD code v. Based on the generated collusion code, the codebook is designed. As a result, when the insert quantity of the fingerprinting code is 0.15% upper in bitplane 0~3 of the Y(luminance) element of I-frame at the video compression of ASF for a streaming service and MP4 for an offline offer of video content, the correlation coefficient of the inserted original code and the detected code is above 0.15. At the correlation coefficient is above 0.1 then the detection ratio of the collusion code is 38%, and is above 0.2 then the trace ratio of the colluder is 20%.

The Influence of Adolescence Abuse Experience to Suicide : Focusing on Policy Implications (청소년의 학대경험이 자살에 미치는 영향 - 정책적 시사점 도출을 중심으로 -)

  • Ryu, Bo-Soon;Kim, Yong-Seob
    • Journal of the Korea Society of Computer and Information
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    • v.17 no.10
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    • pp.193-202
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    • 2012
  • The purpose of this study is to examine the moderating effect of family resilience in the relationship of abuse experience, self-esteem, family resilience, and suicide, and make suggestion for policies to improve family resilience to prevent suicide of the youth with abuse experience. For this, a survey was conducted with 600 people at middle and high schools in three districts in Jeollanamdo, and, except 53 copies, total 547 copies used. The scales used child abuse of Murray A. Straus (1979), suicide of Beck, Kovacs & Weissmen(1979), self-esteem of Coopersmith(1967), and family resilience of Boehm (2007). The results: First, 54.2% of experienced abuse, and, as for the suicide frequency based on abuse types, physical abuse scored high. Second, the regression analysis showed that abuse experience has a direct positive effect on suicide, and higher abuse experience led to more suicide. Also, abuse experience turned out to have indirect effect on suicide through self-esteem, which proves the mediated effect of self-esteem. Third, family resilience was proven to have mediated effect as abuse experience has a negative effect on suicide, and high self-esteem has a negative effect on suicide.

An Effective Method for Blocking Illegal Sports Gambling Ads on Social Media

  • Kim, Ji-A;Lee, Geum-Boon
    • Journal of the Korea Society of Computer and Information
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    • v.24 no.12
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    • pp.201-207
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    • 2019
  • In this paper, we propose an effective method to block illegal gambling advertisement on social media. With the increase of smartphone and internet usage, users can easily access various information while sharing information such as text and video with a large number of others. In addition, illegal sports gambling advertisements are also continue to be transmitted on SNS. To avoid most surveillance networks, users are easily exposed to illegal sports gambling advertisement images by including phrases in the images that indicate illegal sports gambling advertisements. In order to cope with these problems, we proposed a method to actively block illegal sports gambling advertisements in a way different from the conventional passive methods. In this paper, we select words frequently used for illegal sports gambling, classifies them into three groups according to their importance, calculate WF for each word using weighted formula by degree of relevance and frequency, and then sum the WF of the words in the image. Blocking, warning, and passing were determined by cv, the total of WF. Experimenting with the proposed method, 193 out of 200 experimental images were correctly judged with 96.5% accuracy, and even though 7 images were illegal sports gambling advertisements. Further research is needed to block 3.5% of illegal sports betting ads that cannot be blocked in the future.

Optimization of Electro-Optical Properties of Acrylate-based Polymer-Dispersed Liquid Crystals for use in Transparent Conductive ZITO/Ag/ZITO Multilayer Films (투명 전도성 ZITO/Ag/ZITO 다층막 필름 적용을 위한 아크릴레이트 기반 고분자분산액정의 전기광학적 특성 최적화)

  • Cho, Jung-Dae;Kim, Yang-Bae;Heo, Gi-Seok;Kim, Eun-Mi;Hong, Jin-Who
    • Applied Chemistry for Engineering
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    • v.31 no.3
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    • pp.291-298
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    • 2020
  • ZITO/Ag/ZITO multilayer transparent electrodes at room temperature on glass substrates were prepared using RF/DC magnetron sputtering. Transparent conductive films with a sheet resistance of 9.4 Ω/㎡ and a transmittance of 83.2% at 550 nm were obtained for the multilayer structure comprising ZITO/Ag/ZITO (100/8/42 nm). The sheet resistance and transmittance of ZITO/Ag/ZITO multilayer films meant that they would be highly applicable for use in polymer-dispersed liquid crystal (PDLC)-based smart windows due to the ability to effectively block infrared rays (heat rays) and thereby act as an energy-saving smart glass. Effects of the thickness of the PDLC layer and the intensity of ultraviolet light (UV) on electro-optical properties, photopolymerization kinetics, and morphologies of difunctional urethane acrylate-based PDLC systems were investigated using new transparent conducting electrodes. A PDLC cell photo-cured using UV at an intensity of 2.0 mW/c㎡ with a 15 ㎛-thick PDLC layer showed outstanding off-state opacity, good on-state transmittance, and favorable driving voltage. Also, the PDLC-based smart window optimized in this study formed liquid crystal droplets with a favorable microstructure, having an average size range of 2~5 ㎛ for scattering light efficiently, which could contribute to its superior final performance.

A Study on the 7th National Curriculum Implementation at the Secondary School Level - Mathematics - (제 7차 수학과 교육과정 운영에 관한 실태 분석 연구 - 중등학교 단위학교 및 교사 수준을 중심으로 -)

  • Choe Seung-Hyun;Hwang Hye Jeang
    • School Mathematics
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    • v.7 no.2
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    • pp.193-219
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    • 2005
  • This study looked into the procedures of and the status on the implementation of the new mathematics curriculum at the secondary school level(7th through 10th grades). This study examined schools and the teachers were subjects for the actual implementation of the mathematics classroom. More specifically it examined the degree to which the particular innovation ideas of the 7th mathematics curriculum(i.e., reorganization , student-centeredness, diversification/specialization) were being carried out at every stage of the curriculum implementation. Nationwide survey for teachers including students were conducted along with classroom observation and teacher interviews. For an in-depth study into the process and the product of mathematics curriculum implementation, two provincial boards of education participated in the project as research partners. Detailed documentation on the classroom practices were made in order to provide schools and teachers including policy makers with relevant and practical suggestions for further improvement of mathematics curriculum implementation. It was found that mathematics teachers generally were reconstructing the contents giving the priority to the needs of the learners. The concept of learner-centered-ness was reflected in teaching objectives, contents, instructional methods and evaluation. In most schools observed, emphasis was given to the reorganization of the curriculum contents fitting to the concept of 'student-centered' curriculum. The efforts by teachers to diversity and/or specialize the curriculum contents with consideration of various educational conditions such as student readiness, student abilities, classroom equipment and facilities, school locations and environment were found.

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A Study on the Estimation of Object's Dimension based on the Vision System Model of Extended Kalman filtering (확장칼만 필터링의 비젼시스템 모델을 이용한 물체 치수 측정에 관한 연구)

  • Jang, W.S.;Ahn, H.C.;Kim, K.S.
    • Journal of the Korean Society for Nondestructive Testing
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    • v.25 no.2
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    • pp.110-116
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    • 2005
  • It is very important to reduce the computational processing time for the application of the vision system in real time such as inspection, the determination of object's dimension and welding etc, because the vision system model involves a lot of measurement data acquired by CCD camera. Also, a lot of computation time is required in estimating the parameters in the vision system model if the iterative batch estimation method such as Newton Raphson is used. Thus, the effective computation method such as the Extended Kalman Filtering(EKF) is required to solve the above problems. The EKF has much advantages in that it takes explicitly into account the measurement uncertainties, and is a simple and efficient recursive procedures. Thus, this study is to develop the EKF algorithm to compute the parameters in the vision system model in real time. This vision system model involves the six parameters to account for the cameras inner and outer parameters. Also the EKF is applied to estimate the object's dimension. Finally, practicality of the estimation scheme of the vision system based on the EKF is verified experimently by performing the estimation of object's dimension.

Study on Point Defect for $AgGaS_2$ Single Crystal Thin film Obtained by Photoluminescience Measurement Method (광발광 측정법에 의한 $AgGaS_2$ 단결정 박막의 점결함 연구)

  • Hong, Kwang-Joon;Kim, Koung-Suk
    • Journal of the Korean Society for Nondestructive Testing
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    • v.25 no.2
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    • pp.117-126
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    • 2005
  • A stoichiometric mixture of evaporating materials for $AgGaS_2$ single crystal thin films was prepared from horizontal electric furnace. To obtain the single crystal thin films, $AgGaS_2$ mixed crystal was deposited on thoroughly etched semi-insulating GaAs(100) substrate by the hot wall epitaxy (HWE) system. The source and substrate temperatures were $590^{\circ}C\;and\;440^{\circ}C$, respectively The temperature dependence of the energy band gap of the $AgGaS_2$ obtained from the absorption spectra was well described by the Varshni's relation, $E_g(T)=2.7284 eV-(8.695{\times}10^{-4}eV/K)T^2/T(T+332K)$. After the as-grown $AgGaS_2$, single crystal thin films was annealed in Ag-, S-, and Ga-atmospheres, the origin of point defects of $AgGaS_2$ single crystal thin films has been investigated by the photoluminescence(PL) at 10K. The native defects of $V_{Ag},\;V_s,\;Ag_{int},\;and\;S_{int}$, obtained by PL measurements were classified as a donors or acceptors type. And we concluded that the heat-treatment in the Ag-atmosphere converted $AgGaS_2$ single crystal thin films to an optical n-type. Also, we confirmed that Ga in $AgGaS_2$ crystal thin films did not form the native defects because Ga in $AgGaS_2$ single crystal thin films existed in the form of stable bonds.

Assessment of New Algicide Thiazolidinedione (TD49) for the Control of Marine Red Tide Organisms (해양적조생물제어를 위한 살조물질 Thiazolidinedione 유도체(TD49) 평가)

  • Baek, Seung-Ho;Jang, Min-Chul;Joo, Hae-Mi;Son, Moon-Ho;Cho, Hoon;Kim, Young-Ok
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.17 no.1
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    • pp.9-15
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    • 2012
  • Worldwide development of harmful algal blooms causes serious problem for public health and fisheries industries. To evaluate the algicidal impact on the harmful algae bloom species in aquatic ecosystems of coast, a new algicide thiazolidinedione derivative (TD49) were tentatively examined in the growth stages (i.e., lag, logarithmic and stationary phase) of rapidophyceae $Heterosigma$ $akashiwo$, $Chattonella$ $marina$ and $Chattonella$ sp..Three strains could easily destroy in the lag phase due to relatively weak cell walls than those of the logarithmic and stationary phase. It is thought that inoculation of TD49 substances into initial or developmental natural blooms with a threshold concentration ($2{\mu}M$) can maximize the algicidal activity. Also, bio-chemical assays revealed that the algicidal substances from all culture strains were likely to be extracellular substances because those cells have easily destroyed in cell walls. On the other hand, natural zooplankton communities were influenced within the exposure experiments of $2{\mu}M$, which is showed the maximum algcidal activity of tested organisms. These results indicate that although the TD49 substance is potential agents for the control of $H.$ $akashiwo$, $C.$ $marina$ and $Chattonella$ sp. in the enclosed eutrophic bay and coastal water, more detailed research of acute toxicity effect on high trophic organism in marine ecosystems need to be conducted.