• 제목/요약/키워드: Issue Cause

검색결과 669건 처리시간 0.024초

DESIGN AND ANALYSIS OF RANDOMIZED CLINICAL TRIALS REQUIRING PROLONGED OBSERVATION OF EACH PATIENT I. INTRODUCTION AND DESIGN

  • Peto R.;Pike M.C.;Armitage P.;Breslow N.E.;Cox D.R.;Howard S.V.;Mantel N.;Mcpherson K.;Peto J.;Smith P.G.
    • 대한예방의학회:학술대회논문집
    • /
    • 대한예방의학회 1994년도 교수 연수회(역학)
    • /
    • pp.206-233
    • /
    • 1994
  • The Medical Research Council has for some years encouraged collaborative clinical trials in leukaemia and other cancers, reporting the results in the medical literature. One unreported result which deserves such publication is the development of the expertise to design and analyse such trials. This report was prepared by a group of British and American statisticians, but it is intended for people without any statistical expertise. Part!, which appears in this issue, discusses the design of such trials; Part II, which will appear separately in the January 1977 issue of the Journal, gives full instructions for the statistical analysis of such trials by means of life tables and the logrank test, including a worked example, and discusses the interpretation of trial results, including brief reports of particular trials. Both parts of this report are relevant to all clinical trials which study time to death, and would be equally relevant to clinical trials which study time to other particular classes of untoward event: first stroke, perhaps, or first relapse, metastasis, disease recurrence, thrombosis, transplant rejection, or death from a particular cause. Part I, in this issue, collects together ideas that have mostly already appeared in the medical literature, but Part II, next month, is the first simple account yet published for non-statistical physicians of how to analyse efficiently data from clinical trials of survival duration. Such trials include the majority of all clinical trials of cancer therapy; in cancer trials, however, it may be preferable to use these statistical methods to study time to local recurrence of tumour, or to study time to detectable metastatic spread, in addition to studying total survival. Solid tumours can be staged at diagnosis; if this, or any other available information in some other disease is an important determinant of outcome, it can be used to make the overall logrank test for the whole heterogeneous trial population more sensitive, and more intuitively satisfactory, for it will then only be necessary to compare like with like, and not, by chance, Stage I with Stage III.

  • PDF

슈퍼스칼라 프로세서에서 모험적 갱신을 사용한 하이브리드 결과값 예측기 (A Hybrid Value Predictor using Speculative Update in Superscalar Processors)

  • 박홍준;신영호;조영일
    • 한국정보과학회논문지:시스템및이론
    • /
    • 제28권11호
    • /
    • pp.592-600
    • /
    • 2001
  • 슈퍼스칼라 프로세서는 성능향상을 위해 명령어 반입폭과 이슈율을 증가시키고 있다. 데이터 종속성은 ILP(Instruction-Level Parallelism)를 향상시키는데 주요 장애요소가 되고 있으며, 최근 여러 논문에서 데이터 종속성을 제거하기 위해서 명령어의 결과값을 예상하는 메커니즘이 연구되었다. 그러나 이러한 예측기들은 예상한 명령어의 실제 결과값으로 예상 테이블을 갱신하기 전에 그 명령어를 다시 예상할 때 부적절(stale)한 데이터를 사용함으로써 예상 실패율이 증가하여 프로세서의 성능을 감소시킨다. 본 논문에서는 부적절 데이터 사용을 줄여 높은 성능을 얻을 수 있는 새로운 하이브리드 예측 메커니즘을 제안한다. 제안된 하이브리드 결과값 예측기는 예상 테이블을 모험적으로 갱신할 수 있기 때문에 부적절 데이터로 인해 잘못 예상되는 명령어의 수를 효과적으로 감소시킨다. 16-이슈폭 슈퍼스칼라 프로세서에서 SPECint95 벤치마크 프로그램에 대해 모험적 갱신을 사용함으로써 모험적 갱신을 사용하지 않은 경우의 평균 예상 정확도 59%에 비해 평균 예상 정확도가 72%에 비해 평균 예상 정확도가 72%로 크게 향상되었다.

  • PDF

Domestic Constraints of Sino-South Korean Environmental Cooperation: the Case of Trans boundary Air Pollution

  • Shin, Sangbum;Kim, Soelah;Kang, Myeongji
    • 분석과 대안
    • /
    • 제6권1호
    • /
    • pp.163-194
    • /
    • 2022
  • A transboundary environmental problem refers to an environmental problem that goes beyond a country's territory and damages neighboring countries. It is a difficult problem because, basically, it is a natural, rather than intentional, effect, and it is extremely hard to make a scientific consensus on the cause-effect relations between upstream and downstream nations. Air pollution, especially PM 2.5 and PM 10, is one of the typical cases of transboundary environmental problems in the Northeast Asia. This paper analyzes the constraints of environmental cooperation between China and South Korea to address transboundary air pollution issue. It argues that lack of trust and ideological hostility, rather than, scientific uncertainty, is the biggest obstacle for effective cooperation, and these hostile discourses and ideas are mostly generated by media in the downstream nation, the South Korea. In order to identify how South Korean media frames this issue, this paper searched newspaper articles in the six representative South Korean newspapers during the period of 2014 and 2020, and analyzed about 2,000 articles selected. It finds that South Korean media has framed the transboundary air pollution as a China bashing and related domestic political cleavage issue, while it neglects to show the cooperation attempts that the two countries have made to date. Also, while the media focuses on China hate frame, it has never reported the Chinese government's domestic policies to reduce air pollution and their results. Media's overuse of hate and blame frames not only has disrupted trust building but also it will delay a possible turning point of environmental cooperation between the two countries in the future.

이동통신 기반 LPWA (Low Power Wade Area) IoT를 위한 용량 증대 방안 (The Capacity Increase Scheme for Cellular based LPWA (Low Power Wade Area) IoT)

  • 박복녕;정일도
    • 사물인터넷융복합논문지
    • /
    • 제8권4호
    • /
    • pp.17-23
    • /
    • 2022
  • 이동통신사 주도의 LPWA(Low Power Wide Area) 기반 IoT 기술은 NB-IoT와 LTE Cat.M1이 상용화되어 서비스되고 있다. LPWA 기반 IoT에 대한 서비스 요구사항이 증가되면서 이러한 서비스 가입자도 증가하고 있는 상황이다. 서비스 초기에는 NB-IoT 및 LTE Cat.M1을 수용하기 위한 기지국 용량에 이슈가 없었으나, 가입자 증가로 하나의 셀에서 수용하기 위한 용량이 부족해지는 문제가 발생하고 있다. 이러한 Active UE 용량 문제는 지속적인 증가로 인한 과부하와 일시적인 증가로 인한 과부하 문제가 발생할 수 있다. 본 논문에서는 기지국에서 NB-IoT 및 LTE Cat.M1 단말의 일시적인 증가로 인해 발생 하는 LTE 접속제어 채널인 RRC(Radio Resource Control) Active UE 용량 부족 및 기지국 과부하 문제를 해결하기 위한 방안을 제시한다. 제시한 방안은 이동통신의 셀 분할 및 추가 기지국 투자 없이 셀 용량을 증대 시킬 수 있는 방안을 제시함으로써, 증가하는 IoT 단말을 수용해 서비스 성능을 개선시킨다.

복합부위통증증후군(CRPS)에 관한 법적 문제 고찰 - 손해배상소송의 쟁점을 중심으로 - (Study of Legal Issues on Complex Regional Pain Syndrome (CRPS) - Focusing on issues in damage compensation lawsuit -)

  • 배현모
    • 의료법학
    • /
    • 제11권1호
    • /
    • pp.91-116
    • /
    • 2010
  • As Complex Regional Pain Syndrome (CRPS) is a new and rare illness, medical cause for it has not yet been clearly found out. Nevertheless, the patients continue to file lawsuits for damage compensation against wrongdoers or their insurers, claiming that the cause of the illness is certain actions of the wrongdoers. Moreover, the claim amount reaches to hundreds of millions of won through billions of won unlike other illnesses. Therefore, CRPS has become an important legal issue in the damage compensation lawsuit. Even though the wound is slight, the development and result may be serious in the case of CRPS. As a result, a sharp conflict arises even regarding medical diagnosis of CRPS in the lawsuit. And, even if the medical diagnosis of CRPS is admitted, severe debates occurs with regard to many issues, which include the causation between accident and CRPS in connection with establishment of damage compensation liability and scope of liability like anamnesis, determination standard of aftereffect disability, and scope of admitted aftereffect medical expense in connection with scope of damage compensation. In this study, I will review fundamental medical research on CRPS up to now and discuss principal legal issues in the damage compensation lawsuit focusing on lower court rulings.

  • PDF

설계 생산성 향상을 위한 혼-타입 타 설계 프로그램 개발 (Development of Horn-Type Rudder Design Program to Increase Design-Productivity)

  • 이왕수;유용완;최광석;박노준
    • 대한조선학회 특별논문집
    • /
    • 대한조선학회 2009년도 특별논문집
    • /
    • pp.47-51
    • /
    • 2009
  • It is well known that a rudder is influential devices to help ship maintain its stable performances, such as a course-keeping and maneuverability. In the procedures of a commercial ship design proper rudder dimensions (area and shape) ensuring better ship maneuverability have been settled in an initial concept design stage performed by a preceding department, without little structural consideration. It is true that there are time discrepancy between an initial design and a structural analysis stage. Therefore structural analysis results would sometimes cause a rudder to modify its dimensions. Most of these cases, however, ship design and performance tests had been finished. In this matter, only limited modifications of redder could be carried out. Besides, these could also cause bad effects on productivity. Finally, it is necessary to develop a new program considering co-relationship between an initial rudder design and a following work, a structural strength analysis, in order to enhance productivity and minimize a rate of redesign procedures.

  • PDF

DC 궤도회로의 효율적인 운용방법에 대한 연구 (A study on efficient operation of DC track circuit)

  • 장동완;전태현
    • 조명전기설비학회논문지
    • /
    • 제28권2호
    • /
    • pp.70-75
    • /
    • 2014
  • A track circuit is a critical piece of equipment that allows the existence of the trains on the track to be detected. Train detection is very important for the signal safety equipment. It allows for the confirmation of a train's location, the locking of switch points, the coordination of safe distance between trains, and the advance notice of a train's arrival. Track circuits can be powered by AC or DC. The DC track circuits are usually used on non-electrified tracks. On these tracks, many signal errors can be caused by lightning or problems with the power source. These problems can also cause damages to the rectifiers which must be repaired or replaced, promptly. This issue is especially problematic in the summer because of the higher frequency of thunderstorms. Issues with track circuits also cause problems for other equipment, such as railroad crossings and switch points. This further disrupts the safe operation of trains. This study aims to enhance maintenance efficiency and improve safety by utilizing parallel operation and multiplexing of a DC track circuit as well as installing an external surge protector. The experimental results on the operation of the proposed method is also presented.

『황제내경(黃帝內經)』의 뇌수소삭(腦髓消爍)에 대한 소고(小考) (A Study on Naosuixiaoshuo in Huangdineijing)

  • 김범석;백유상
    • 대한한의학원전학회지
    • /
    • 제31권1호
    • /
    • pp.127-138
    • /
    • 2018
  • Objectives : The paper reviews the texts related to Naosuxiaoshuo in Huangdineijing, and investigates its cause, mechanism, prognosis and symptom expressions. Methods : The paper searches for the texts within Huangdineijing that deal with Naosuxiaoshuo, and tries to clarify the significance and the characteristics of Naosuxiaoshuo using the annotators comments regarding this issue. Moreover, the paper tries to search for similarities between the symptoms of Naosuxiaoshuo and the relevant diseases in modern medicine. Results : Naosuxiaoshuo is a serious disease where the diminishing of the brain's parenchyma can even lead to death. The cause is yin-deficiency based on the lack of vital essence and body fluid, and it also can be caused by the external pathogen or other stimulations. Moreover, it shows some similarities with brain atrophy and cerebrospinal fluid diseases. Conclusions : Naosuxiaoshuo should be treated with a focus on yin-tonifying dealing with spleen related to production of body fluid and the kidney related to storage of vital essence. It is also important to prevent external pathogens or stimulations damaging the bone marrow.

필렛용접에서의 결함발생 원인 분석 및 저감 방안 (An Analysis of the Cause of Porosity Generation and Reduction Plan in Fillet Welding)

  • 최기영;김영필;김경주;김대순;배상득
    • 대한조선학회 특별논문집
    • /
    • 대한조선학회 2006년도 특별논문집
    • /
    • pp.128-133
    • /
    • 2006
  • Generally, porosity which was formed by pyrolysis of the primer is usually generated in the weld metal in respect of increase of the welding speed. in order to analyze the cause of porosity generation, this study was performed using FCAW(flux cored arc welding) process for three kinds of inorganic.zinc primer. in addition the evaluation by influence of welding method on porosity generation is conducted to compare between FCAW and MAG(metal active gas) welding with the same inorganic zinc primer. As the result of this investigation, not only primer of lower organic binder and zinc but also FCAW process than MAG in fillet welding have been verified the excellent resistance to the porosity generation for horizontal fillet welding.

  • PDF

화약류작업에서 인적오류에 대한 분석 (An Analysis of Human Errors in Gun Powder Jobs.)

  • 이정훈;안명석;김종현
    • 화약ㆍ발파
    • /
    • 제22권3호
    • /
    • pp.97-101
    • /
    • 2004
  • 건설현장에서 도로개설, 터널굴착, 시가지 고층건물 지하굴착 등으로 화약류의 사용은 날로 증가되고 있으며, 이로 인한 화약류의 사고도 비례하여 증가하고 있어 점차 사회문제화 되고 있다. 본 연구에서는 이미 개발된 발파사고의 분석에 필요한 사고조사표와 이를 이용하여 발파사고를 체계적으로 분석한 FTA기법 분석에서 발파사고 중 가장 많은 비율을 차지하는 인적원인에 대한 체크리스트를 개발하였으며, 이를 이용한 현장에서의 적용에 대한분석을 실시하였다. 그 결과 발파작업 중 가장 힘들고 불편한 공정인 장전작업에서 가장 많은 오류가 발생하였으므로 이에 대한 개선 작업에 관심을 기울여야 할 것으로 생각된다.