• Title/Summary/Keyword: Ghost problem

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Evaluation of High Absorption Photoconductor for Application to Auto Exposure Control Sensor by Screen Printing Method (자동노출제어장치 센서적용을 위한 스크린 프린팅 제작방식의 고흡수율 광도전체 특성평가)

  • Kim, Dae-Kuk;Kim, Kyo-Tae;Park, Jeong-Eun;Hong, Ju-Yeon;Kim, Jin-Seon;Oh, Kyung-Min;Nam, Sang-Hee
    • Journal of the Korean Society of Radiology
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    • v.9 no.2
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    • pp.67-72
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    • 2015
  • In diagnostic radiology, the use of automatic exposure control device is internationally recommended for diagnosis and optimization. However, if exposed to prolonged radiation is a complicated manufacturing process, there is a problem that occurs decrease of various performance overall brightness sensor, which is commercially available conventional. Therefore, in this study, absorption of X-ray is high, and I want to evaluate the AEC applicability of the sensor of the photoconductor-based production has an easy advantage. Experimental results confirms the possibility of fabrication of the sensor through an increase in the SNR, with the detection efficiency superior, accurate turn-off. In addition, it is confirmed that the experimental results of the transmittance and the latent image, Ghost effect by the light conductor does not appear, in the case of a photoconductor with the exception of the PbO, 80% - and it was confirmed good transmittance of 90%. Therefore, excellent mechanical stability and poor performance due to a change of the doping concentration than the existing products that have been put to practical use, the sensor easy photoconductor based, fabrication and can be applied as AEC sensor is expected.

Weatherability of biodegradable polybutylene succinate(PBS) monofilaments (생분해성 PBS monofilament의 내후성)

  • Park, Seong-Wook;Bae, Jae-Hyun
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.44 no.4
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    • pp.265-272
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    • 2008
  • Biodegradable polybutylene succinate(PBS) is an environment friendly plastics for fisheries, because it can mitigate the ghost fishing problem caused by gill-net and trap fisheries. To evaluate photodegradability of PBS monofilament in comparison with polyamide(PA) and polyethylene(PE) monofilament, these 3 types of monofilaments were spun and exposed to ultraviolet light(UV) of weather-ometer for 900 hours, and then their modification, crystal structure, strength, and extensibility were analysed. PBS monofilament did not show any crack and maintained its crystal structure after 900 hour exposure to UV whereas PE monofilament began showing cracks and structure modification after 600 hour exposure. Under UV exposure, the strength and extensibility decreased more rapidly in PBS than in PA and PE. We estimate that gill nets made of PBS monofilament can endure for about 1 year. The breaking strength and elongation decreased linearly with the exposure time for the 3 types of monofilaments. The derived regression equations of the residual tenacity(RT, kg/$mm^2$) and the residual extensibility(RE, %) with the exposure time in year(Y) for each monofilament were; PBS : RT=48.598 - 8.6437Y($R^2=0.93$), RE=28.165 - 7.3233Y($R^2=0.98$), P A : RT=59.771 - 8.6437Y($R^2=0.98$), RE=32.198 - 5.2772Y($R^2=0.92$), P E : RT=60.898 - 5.6528Y($R^2=0.98$), RE=11.887 - 0.7188Y($R^2=0.98$).

Performance Improvement of Terrestrial DTV Receivers Using Frequency-domain Equalization (주파수 영역 등화를 이용한 지상파 DTV 수신 성능 개선)

  • Son Sang-Won;Kim Ji-Hyun;Kim Hyoung-Nam
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.31 no.4C
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    • pp.351-363
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    • 2006
  • The 8-VSB modulation, the transmission standard for the terrestrial digital television(DTV) of the Advanced Television Systems Committee(ATSC), suffers from multipath fading because it conveys information on the amplitude. To solve this problem, decision feedback equalizers(DFE's) have been commonly used in terrestrial DTV receivers. However, under severe channels, such as a 0 dB ghost channel or a single frequency network (SFN) channel, the DFE shows unstable convergence due to the error propagation caused by decision errors. Instead of unstable time-domain DFE schemes, by proposing a frequency-domain direct-inversion equalization method, we try to guarantee stable equalization and achieve low symbol error rates. To secure the existence of a channel inverse, channel-matched filtering and noncausal filtering are carried out prior to equalization. Simulation results show that the proposed method performs much better than existing DFE schemes in terms of both the stability and the symbol error rate.

Fishing power estimation of biodegradable traps in the East Sea (동해 생분해성 통발의 어획성능 평가)

  • Bae, Bong-Seong;An, Heui-Chun;Jeong, Eui-Cheol;Park, Hae-Hoon;Park, Seong-Wook;Park, Chang-Doo
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.46 no.4
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    • pp.292-301
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    • 2010
  • For an effective management of fisheries resources, it is very important that to make clean inhabitation environment and to preserve fisheries resources. The material which is mainly used as fishing gear in modern times, is polyethylene, polypropylene, polyamide, etc., chemical fiber. And lost fishing gears which are make of these, occur ghost fishing and ocean pollution. To solve these problem, we development biodegradable fishing trap using the polybutylene succinate (PBS). Developed traps are for red snow crab (Chionoecetes japonicus) and shrimp, major traps in the East Sea, and we carried out fishing research using two kind traps in the coastal sea of Ayajin-port (Goseong) to analysis fishing efficiency of PE trap and PBS trap. As a result for fishing experiment (year 2005-2006) of red snow crab trap, two kind traps were almost the same in catches and length composition. During a experiment, parts of meshes, used for over 1 year, were cut by biodegradation. As a result for fishing experiment (year 2007) of shrimp trap, northern shrimp (Pandalus eous), coonstripe shrimp (Pandalus hypsinotus) and morotoge shrimp (Pandalopsis japonica) were catched, and the almost is northern shrimp. Two kind traps were almost the same in catches and length composition. In accordance with these result, it is recommended that the developed traps are have to commercialized because the fishing powers of PE traps and PBS traps were same. But biodegradation speed is have to controled in consideration of ocean microorganism volume and traps life.

New typhoid vaccine using sponge-like reduced protocol: development and evaluation

  • Rehab Bahy;Asmaa Gaber;Hamdallah Zedan;Mona Mabrook
    • Clinical and Experimental Vaccine Research
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    • v.12 no.1
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    • pp.70-76
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    • 2023
  • Purpose: Typhoid remains a major health problem, especially in the developing world. Furthermore, the emergence of multidrug-resistant and extensively drug-resistant strains of Salmonella typhi added a sense of urgency to develop more effective typhoid vaccines, one of which is bacterial ghosts (BGs), prepared by both genetic and chemical means. The chemical method includes incubation with numerous agents for a short time at their minimum inhibitory or minimum growth concentrations. This study included the preparation of BGs by a sponge-like reduced protocol (SLRP). Materials and Methods: Critical concentrations of sodium dodecyl sulfate, NaOH, and H2O2 were used. Moreover, high-quality BGs were visualized by scanning electron microscope (SEM). Subculturing was used to confirm the absence of vital cells. Besides, the concentrations of the released DNA and protein were estimated spectrophotometrically. In addition, the integrity of cells was proved by visualizing Gram-stained cells using a light microscope. Furthermore, a comparison between the immunogenicity and safety of the prepared vaccine and the available whole-cell killed vaccine was established. Results: Improved preparation of high-quality BGs of S. typhi, visualized by SEM, revealed punctured cells with intact outer shells. Moreover, the absence of vital cells was confirmed by subculturing. At the same time, the release of respective amounts of proteins and DNA is another evidence of BGs' production. Additionally, the challenge test provided evidence that the prepared BGs are immunogenic and have the same efficacy as the whole cell vaccine. Conclusion: The SLRP provided a simple, economical, and feasible method for BGs preparation.

Authorship and Inappropriate Authorship from an Ethical Publication Perspective (출판 윤리적 관점에서의 저자됨과 부적절한 저자됨)

  • Sung Hun Kim;Jung Im Jung
    • Journal of the Korean Society of Radiology
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    • v.83 no.4
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    • pp.752-758
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    • 2022
  • Authorship is important for research integrity and publication ethics, acting as the basis for credit and academic achievement. Moreover, publication achievements have a significant impact on research grants and academic careers. Inappropriate authorship has been reported for several reasons, including complex interests and competitive environments. One form of this is representative authorship misuse, which includes honorary and ghost authorships. Kin co-authorship, such as parent-children authorship, is another form of inappropriate authorship that has recently emerged as a social problem in Korea. To address these issues, the International Committee of Medical Journal Editors (ICMJE) has established criteria for authorship. Similarly, many journals use the Contributor Roles Taxonomy (CRediT) and Open Researcher and Contributor ID (ORCID) systems to prevent authorship misuse and systematically evaluate author credit and responsibility. Herein, this article reviews authorship and inappropriate authorship, as well as introduces methods to avoid authorship misuse.

Comparative Studies on the Analysis of Pesticide Residues. in Rice, Barley and Wheat (주곡중의 잔류농약분석에 관한 연구)

  • Park Seung Heui
    • Korean journal of applied entomology
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    • v.13 no.4 s.21
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    • pp.235-243
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    • 1974
  • Recenty, the pesticides Pollutions in connection with the maintenance of dietary life are poised as serious sanitary problems. Author have established an appropriate analysis method in this connection and, at the same time, analysed the levels of pesticides residues, such as organochloride pesticides and organic mercurials, contained in main cereals (rice, barley, and wheat) collected throughout the country. Using gas liquid chromatography method, comparative analyses were made of organochloride Pesticides with electron capture detector, and organic mercurials with electron capture detector and the Dithizone Method. As a result, the organic mercurials analysis using gas liquid chromatography is believed to hold out an especially good method for both in terms of its sensitivity and its Practical applications. The summary obtained from these results is as follows; The detectable limit of organochloride pesticides is $5\times10^{-10}$ grams and that of organic mecurials is $5\times10^{-9}$ grams. The detections using the Dithizone Method are difficult. The gas liquid chromatographic analysis of organic mercurials is very simple in its operation and high in its sensitivity, compare with the analysis using the Dithizone Method. Therefore, this analysis is expected to be a good method applicable to the pesticide residues analysis. The levels of pesticide residues contained in samples are very little for tolerance and, therefore, no problem i.: foreseen for eating. The appropriate conditions of gas liquid chromatographic analysis obtained from these results are expected very useful for the date establishing an officially authorized analysis method.

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Block Replacement Scheme based on Reuse Interval for Hybrid SSD System (Hybrid SSD 시스템을 위한 재사용 간격 기반 블록 교체 기법)

  • Yoo, Sanghyun;Kim, Kyung Tae;Youn, Hee Yong
    • Journal of Internet Computing and Services
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    • v.16 no.5
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    • pp.19-27
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    • 2015
  • Due to the advantages of fast read/write operation and low power consumption, SSD(Solid State Drive) is now widely adopted as storage device of smart phone, laptop computer, server, etc. However, the shortcomings of SSD such as limited number of write operations and asymmetric read/write operation lead to the problem of shortened life span of SSD. Therefore, the block replacement policy of SSD used as cache for HDD is very important. The existing solutions for improving the lifespan of SSD including the LARC scheme typically employ the LRU algorithm to manage the SSD blocks, which may increase the miss rate in SSD due to the replacement of frequently used block instead of rarely used block. In this paper we propose a novel block replacement scheme which considers the block reuse interval to effectively handle various data read/write patterns. The proposed scheme replaces the block in SSD based on the recency decided by reuse interval and age along with hit ratio. Computer simulation using workload trace files reveals that the proposed scheme consistently improves the performance and lifespan of SSD by increasing the hit ratio and decreasing the number of write operations compared to the existing schemes including LARC.

60 Years since the Armistice Treaty, the NLL and the North-Western Islands (정전협정 60년, NLL과 서북 도서)

  • Jhe, Seong-Ho
    • Strategy21
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    • s.31
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    • pp.27-56
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    • 2013
  • The United Nations Command (UNC) and the communist North failed to reach an agreement on where the maritime demarcation line should be drawn in the process of signing a truce after the Korean War because of the starkly different positions on the boundary of their territorial waters. As a result, the Armistice Treaty was signed on July 1953 without clarification about the maritime border. In the following month, Commander of the UNC unilaterally declared the Northern Limit Line (NLL) as a complementing measure to the Armistice. Referring to this, North Korea and its followers in South Korea wrongfully argue that the NLL is a "ghost line" that was established not based on the international law. However, one should note that the waters south of the NLL has always been under South Korea's jurisdiction since Korea's independence from Japan on August 15, 1945. There is no need to ask North Korea's approval for declaring the territorial waters that had already been under our sovereign jurisdiction. We do not need North Korea's approval just as we do not need Japan's approval with regard to our sovereign right over Dokdo. The legal status of the NLL may be explained with the following three characteristics. First, the NLL is a de facto maritime borderline that defines the territorial waters under the respective jurisdiction of the two divided countries. Second, the NLL in the West Sea also serves as a de facto military demarcation line at sea that can be likened to the border on the ground. Third, as a contacting line where the sea areas controlled by the two Koreas meet, the NLL is a maritime non-aggression line that was established on the legal basis of the 'acquiescence' element stipulated by the Inter-Korea Basic Agreement (article 11) and the Supplement on the Non-aggression principle (article 10). Particularly from the perspective of the domestic law, the NLL should be understood as a boundary defining areas controlled by temporarily divided states (not two different states) because the problem exists between a legitimate central government (South Korea) and an anti-government group (North Korea). In this sense, the NLL problem should be viewed not in terms of territorial preservation or expansion. Rather, it should be understood as a matter of national identity related to territorial sovereignty and national pride. North Korea's continuous efforts to problematize the NLL may be part of its strategy to nullify the Armistice Treaty. In other words, North Korea tries to take away the basis of the NLL by abrogating the Armistice Treaty and creating a condition in which the United Nations Command can be dissolved. By doing so, North Korea may be able to start the process for the peace treaty with the United States and reestablish a maritime line of its interest. So, North Korea's rationale behind making the NLL a disputed line is to deny the effectiveness of the NLL and ask for the establishment of a new legal boundary. Such an effort should be understood as part of a strategy to make the NLL question a political and military dispute (the similar motivation can be found in Japan's effort to make Dokdo a disputed Island). Therefore, the South Korean government should not accommodate such hidden intentions and strategy of North Korea. The NLL has been the de facto maritime border (that defines our territorial waters) and military demarcation line at sea that we have defended with a lot of sacrifice for the last sixty years. This is the line that our government and the military must defend in the future as we have done so far. Our commitment to the defense of the NLL is not only a matter of national policy protecting territorial sovereignty and jurisdiction; it is also our responsibility for those who were fallen while defending the North-Western Islands and the NLL.

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A Study on the Regimen thought of Baopuzi inner chapters (『포박자내편(抱朴子內篇)』의 양생사상 연구)

  • Shin, Jin Sik
    • The Journal of Korean Philosophical History
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    • no.43
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    • pp.231-266
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    • 2014
  • The main contents of Baopuzi inner chapters becomes the basis for the claim "to be achieved Xian the way people can be" named and Shenxian theory that is deployed in the center of the universe body theory with a focus on Xuan and YI and Tao and a problem of "demonstration of Shenxian exist", or ancient science that describes the Chinese alchemy and Taoism spell in other words, inner chapters are writing and how to get prescription way of Shenxian, of medicine to become a predecessors, elephant of some of the changes in the ghost apparition, the longevity, how to avoid the epidemic out of the evil. Inner chapters are presented a regimen thought, the rationale for its mystical religion and philosophy of Monasticism ship on the basis of the theory Shenxian so. Baopuzi Inner chapters is presented in detail how to reach a comprehensive and realistic Shenxian long life in prison without the pre-Qin dynasty Taoism and Qinhan dynasty and times across the Weijin dynasty Shenxian ideas. And is presented in a typical Waidan and Neidan Taoism exercise this system and that in Taoism (Regimen) Thought the important position. Thought of Regimen is very important right information Inner chapters which constitutes the establishment of an important theoretical basis Shenxian Taoism of Gehong this research right in that you can see at a glance the thought of Regimen of Inner chapters is the desperate need for this requirement. It aims to illuminate the entire look of Regimen ever appeared immediately in Inner chapters this paper. After the analysis of the body Tao theory, The theory of the body and the spirit, The theory of Xingming, The theory of Shenxian theoretical foundations of thought appeared in Inner chapters Based on this, the first one conducted regulating the qi flowing in the channels method, Daoyin method, Pranayama, Closed breath, I saw one at the specifics of regimen method such, art of controlling and swallowing breath from the mouth, Convinced, Tuna breathing, Sishenshouyi method, Jinehuandan method, Fangzhongshu. And reporting features found Inner chaptersfinally saw the spirit of Regimen weigh its value.