• 제목/요약/키워드: Controversy

검색결과 812건 처리시간 0.039초

스펙트럼 파랑모형에서의 쇄파모형 (Modeling of Wave Breaking in Spectral Wave Evolution Equation)

  • 조용준;유하상
    • 한국해안해양공학회지
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    • 제19권4호
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    • pp.303-312
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    • 2007
  • 주파수영역에서 쇄파로 인한 에너지 소산에 관한 그 동안의 논쟁은 주파수의 함수인 소산항의 구체적 형태를 중심으로 진행되어왔다. 본 연구에서는 추계학적 쇄파모형과 이에 기초한 스펙트럼으로부터 소산항을 유추하였다. 기존의 인식과는 상이하게 소산항은 주파수의 삼차함수인 것으로 판단된다. 검증작업은 SUPERTANK Laboratory Data Collection Project(Krauss et al., 1992)에서 축적된 실험자료를 기초로 진행되었다. 추가적인 검증을 위해 단조해안에서의 Cnoidal 파랑의 천수과정을 스펙트럼 파랑모형과 제시된 쇄파모형을 차용하여 수치모의하였다. 그 결과 쇄패대역에서 진행되는 파랑의 왜도와 비대칭성의 진화과정이 비교적 정확히 모의되는 성과를 얻었다.

갑상선 혈종의 보존적 치료 1예 (A case of Thyroid Hematoma Managed by Conservative Treatment)

  • 정영도;김덕수;손호진;김정규
    • 대한두경부종양학회지
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    • 제34권1호
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    • pp.45-47
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    • 2018
  • Thyroid hematoma secondary to a blunt trauma is a rare problem. Despite the rarity, it can be a life-threatening condition with tracheal compression. Both surgical exploration and conservative management have been suggested for thyroid hematoma. However, there is still controversy on the optimal treatment. A 67-year old man who progressed severe dyspnea and neck swelling was transferred to the emergency department with a blunt anterior neck trauma after traffic accident. Contrast enhanced neck computed tomography scan showed huge hematoma within the right thyroid gland and slight tracheal deviation without prominent airway obstruction. One day later, anterior neck swelling was aggravated and the patient was intubated to prevent airway obstruction. After 3 days, hematoma resolution was revealed and extubation was done. We report this case with a review of literature.

A Subjectivity Study on the Promotion of Korean Smart TV Industry through Q Methodology

  • Kim, Ki Youn;Cho, Dae Keun;Song, In Kuk
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제8권6호
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    • pp.2171-2185
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    • 2014
  • From the perspectives of regulation and convergence, several debates on the industrial definition of smart TV service in the Korean broadcasting and communications market are currently in progress. The most heated controversy mainly depends on whether smart TV is controlled under broadcasting regulations or under communications regulations. This Korean- specific problem is summarized in regulation fairness or asymmetric regulations between smart TV and IPTV operators. Although both operators utilize very similar technology and share the same business model, the regulations for only smart TV operators are unfettered. This would be an intrinsic cause that prohibits fair competition in the new converging market. Currently we confront the matter of asymmetric regulations between smart TV and others including IPTV or ISP. The purpose of this study, thus, is to provide the strategic, regulatory guidance and theoretical definitions on smart TV service, as one of converging services, based on a qualitative approach through subjectivity methodology. The study identifies three issues net neutrality, regulation fairness and new media and new market and proposes desirable promotion plans regarding those issues. The study draws lessons learned through a Korean smart TV case and provides directions to strategic-policy studies for future emergent converging services.

Cameroon : The Effect of Developmental AID on Poverty Reduction and Agro-Rural Development in Sub-Saharan Africa

  • Ntongwe, Edwin Ngome
    • Agribusiness and Information Management
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    • 제4권1호
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    • pp.1-12
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    • 2012
  • Cameroon, with her numerous resources, still depends on foreign aid while the rate of poverty remains high. Thus, even though historical evidence gives impetus to the impasse over role of developmental aid, from the top down approach through to development as a springboard raising states from the doldrums of poverty, it is still very difficult to draw a substantial relationship between developmental aid and poverty reduction. Against this backdrop of controversy, I find it apt to put Cameroon on a balance scale. Therefore, the purpose of this research is to critically assess the implications of developmental aid on poverty reduction and agro-rural development in Cameroon, using the RUMPI Area Development Project in the South West region of Cameroon as a case study. The study will situate and contextualize the top-down and bottom-up approaches to development within the basis of a Cameroonian perspective, using the Sachs-Easterly debate. The RUMPI Project was introduced with the objective of improving agriculture and empowering the rural woman; thereby fighting poverty within the South West region of Cameroon. Despite its criticism of the barriers to development created by corruption, political pressure and limited use of local and grass-root partnerships, the study, in assessing these failures also tries to outline vital ways in which the project can be improved upon.

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Molecular gas properties under ICM pressure : A Case study of NGC4402

  • 한유진;정애리
    • 천문학회보
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    • 제36권2호
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    • pp.117.2-117.2
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    • 2011
  • We probe 12CO J=2-1 and 13CO J=1-0 properties of a Virgo disk galaxy, NGC 4402 which is located near the cluster center. Our goal is to study the impact of intra cluster medium (ICM) on the molecular gas of a galaxy in the cluster environment. It has been believed that cluster galaxies are deficient in atomic hydrogen gas (HI gas) compared to their field counterparts and now there is much evidence that low density ISM can be easily removed by ram pressure caused by ICM wind. Meanwhile, no significant molecular gas deficiency of the cluster galaxy population has been found yet they show overall lower star formation rate than galaxies in the field, and it is still controversy whether dense ISM can be also stripped by the ICM wind or not. NGC 4402 with truncated HI disk($D_{HI}/D_{opt}$ ~ 0.75 and only 36%of HI gas compare to field galaxies of a similar size) and a disturbed gas morphology, appears to have strong ongoing ram pressure. Using high resolution 12 and 13CO data of NGC 4402 from a Sub Millimeter Array (SMA), we probe the molecular gas properties under strong ICM pressure. We discuss how its star formation activity and hence the global color of NGC4402 would be changed in the future.

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TTP 보안 서비스 레벨에서 효율성과 공정성을 고려한 부인봉쇄 프로토콜 (Non-repudiation Protocol for Efficiency and Fairness in TTP Security Service Level)

  • 박상준;홍충선;이대영
    • 한국통신학회논문지
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    • 제26권11C호
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    • pp.24-32
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    • 2001
  • 최근 인터넷 등과 같은 전자적인 서비스에서 약속된 프로토콜에 위반한 송수신자 쌍방간의 행위에 대한 기술적인 증거를 제공하고, 논쟁 발생 시 법적 근거로 제공할 수 있게 해주는 서비스로 부인봉쇄 서비스가 있다. 본 논문에서는 부인봉쇄 서비스를 위해 필요한 제 3의 신뢰기관인 TTP(Trusted Third Party)의 기능을 확장시켜 부인 봉쇄 서비스에서의 효율성을 항상시키고, 동시에 공정성을 제공하는 프로토콜을 제안한다. 본 논문에서는 TTP의 기능을 확장시키기 위하여 Time Check기능과 Alert Message를 적용하여 모의실험결과 기존에 연구되어진 부인봉쇄 프로토콜보다 효율성이 증가함을 알 수 있었다.

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Prognosis of Maxillary Sinus Augmentation in the Presence of Antral Pseudocyst: Case Reports

  • 마득현;김수관;오지수;유재식;김원기;양정은;임형섭
    • 대한치과의사협회지
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    • 제54권10호
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    • pp.771-779
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    • 2016
  • Purpose: Antral pseudocyst is a common benign lesion that exists in the maxillary sinus. Because of this possible complication, controversy remains with respect to sinus floor elevation operations. The purpose of this study was to analyze the antral pseudocyst related to maxillary sinus augmentation. Patients and Methods: The radiographs of 268 patients who visited Chosun University Dental Hospital from 2008 to 2010 and underwent the maxillary bone grafting procedure were examined. Results: Of the 268 patients who underwent the maxillary bone grafting procedure, 5 patients (1.86%) were diagnosed with antral pseudocysts. In all cases, maxillary sinus floor elevation was performed without aspiration, biopsy or extraction of the antral pseudocyst. Conclusion: Antral pseudocysts are not considered a contraindication for maxillary sinus bone grafting procedure.

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의료용 대마(大麻)의 이해 및 법적 규제에 대한 고찰: 대마의 치료적, 학술적 필요성 제고 (Understanding of Medical Cannabis and its Regulations: A Suggestion for Medical and Scientific Needs)

  • 한경선;이명종;김호준
    • 한방비만학회지
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    • 제16권2호
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    • pp.124-132
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    • 2016
  • In traditional medicine, Cannabis sativa L. has been used for variety of reasons. Old literatures delineate that Cannabis had been used as anesthetic and analgesic, or to reduce symptoms such as cough, paralysis and so on. Although Cannabis has a long history of medical use, it is illegal in many countries including South Korea. Controversy over decriminalization of Cannabis to allow cannabis for therapeutic use has been around for many years. In order to understand current knowledge on the therapeutic use of medical Cannabis, comprehension of cannabinoids and other constituents of Cannabis is important. Here we reviewed the pharmacological effect of Cannabis and current mandatory regulation over Cannabis in many countries to suggest necessity of research on medical Cannabis.

질소이온 주입이 생체적합성 티타늄 임플란트의 마모특성에 미치는 영향 (Effect of Nitrogen Ion Implantation on Wear Behavior of Biocompatible Ti Implant)

  • 변응선;김동수;이구현;정용수
    • 연구논문집
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    • 통권30호
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    • pp.137-145
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    • 2000
  • Since the concept of osseointegration was introduced, titanium and titanium-based alloy materials have been increasingly used for bone-anchored metal in oralmaxillofacial and orthopedic reconstruction. Successful osseointegration has been attributed to biocompatibility and surface condition of metal implant among other factors. Although titanium and titanium alloys have an excellent over the metal ion release and biocompatibility, considerable controversy has developed over the metal ion and wear debris in vivo and vitro. In this study, nitrogen ion implantation technique was used to improve the corrosion resistance and wear property of titanium materials, ultimately to enhance the tissue reaction to titanium implants As ion implantation energy was increased, projected range of nitrogen ion the Ti substrate was gradually increased. Under condition of constant ion energy. atomic concentration of nitrogen was also increased with ion doses. The friction in Hank's solution was increased with ion doses. The friction coefficient of ion implanted specimens in HanK's solution was increased from 0.39, 0.47 to 0.52, 0.65 respectively under high energy and ion dose conditions. As increasing ion energies and ion dose, amount of wear was reduced.

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Origin of Multiple Conductance Peaks in Single-Molecule Junction Experiments

  • Park, Min Kyu;Kim, Hu Sung;Kim, Yong-Hoon
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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    • pp.654-654
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    • 2013
  • One of the most important yet unresolved problems in molecular electronics is the controversy over the number and nature of multiple conductance peaks in single-molecule junctions. Currently, there are three competing explanations of this observation: (1) manifestation of different molecule-electrode contact geometries, (2) formation of gauche defects within the molecular core, (3) involvement of different electrode surface orientations [1]. However, the exact origin of multiple conductance peaks is not yet fully understood, which indicates our incomplete understanding of the scientifically as well as techno-logically important organic-metal contacts. To theoretically resolve this problem, we previously applied a multiscale computational approach that combines force fields molecular dynamics (FF MD), density functional theory (DFT), and matrix Green's function (MGF) calculations [2] to a thermally fluctuating haxanedithiol (C6DT) molecule stretched between flat Au(111) electrodes, but could observe only a single conductance peak [3]. In this presentation, using DFT geometry optimizations and MGF calculations, we consider molecular junctions with more realistic molecule-metal contact conformations and Au(111) electrode surface directions. We also conduct DFT-based molecular dynamics for the highly stretched junction models to confirm our conclusion. We conclude that the S-Au coordination number should be the more dominant factor than the electrode surface orientation.

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