• 제목/요약/키워드: unusual data

검색결과 283건 처리시간 0.023초

뇌 CT에서 출혈로 오인된 소뇌의 허상: 증례보고 (Unusual Brain Computed Tomography Artifact in Cerebellum Mimicking Hemorrhage: A Case Report)

  • 이지훈;엄기성;김태영
    • Journal of Trauma and Injury
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    • 제28권3호
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    • pp.195-197
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    • 2015
  • Artifacts can seriously degrade the quality of computed tomography (CT) images, sometimes to the point of making them diagnostically unusable. Here, we report an unusual CT artifact that could have resulted in the misdiagnosis of a hyperdense hemorrhagic lesion in a 55-year-old man. The author recommend that when hemorrhagic lesion in posterior fossa is suggested on CT, the physician should carefully consider all patient-related clinical data prior to considering surgical intervention or a biopsy. Cranial magnetic resonance imaging (MRI) can help in preventing the misdiagnosis as hemorrhage of CT scan.

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2002년 8월의 집중호우와 저온현상 (Agricultural Implications of Rainfall Events and Low Temperature in August 2002)

  • 이양수;심교문;황규홍;고문환
    • 한국농림기상학회지
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    • 제4권3호
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    • pp.169-174
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    • 2002
  • When the long - lasting stationary fronts were pushed northward by the Pacific Highs in late July, mostly clear skies with intermittent showers were a typical weather of August in Korea. However, torrential rains and flash floods are now a seasonal event of August in recent years. Some meteorologists suspect this unusual phenomenon might be connected with the global change and are concerned about the possibility of change in summer climatic pattern in Korea. August of year 2002 must be remembered to be one of the record breaking months with respect to the rainfall events. In this paper, we analyzed the weather and crop data nationwide for August in 2002, and suggest a few countermeasures necessary to overcome the wet and cool summer impacts on agricultural sector.

Local Influence of the Quasi-likelihood Estimators in Generalized Linear Models

  • Jung, Kang-Mo
    • Communications for Statistical Applications and Methods
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    • 제14권1호
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    • pp.229-239
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    • 2007
  • We present a diagnostic method for the quasi-likelihood estimators in generalized linear models. Since these estimators can be usually obtained by iteratively reweighted least squares which are well known to be very sensitive to unusual data, a diagnostic step is indispensable to analysis of data. We extend the local influence approach based on the maximum likelihood function to that on the quasi-likelihood function. Under several perturbation schemes local influence diagnostics are derived. An illustrative example is given and we compare the results provided by local influence and deletion.

Development of an Event Stream Processing System for the Vehicle Telematics Environment

  • Kim, Jong-Ik;Kwon, Oh-Cheon;Kim, Hyun-Suk
    • ETRI Journal
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    • 제31권4호
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    • pp.463-465
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    • 2009
  • In this letter, we present an event stream processing system that can evaluate a pattern query for a data sequence with predicates. We propose a pattern query language and develop a pattern query processing system. In our system, we propose novel techniques for run-time aggregation and negation processing and apply our system to stream data generated from vehicles to monitor unusual driving patterns.

Unusual Enhancements of NmF2 in Anyang Ionosonde Data

  • Yun, Jongyeon;Kim, Yong Ha;Kim, Eojin;Kwak, Young-Sil;Hong, Sunhak
    • Journal of Astronomy and Space Sciences
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    • 제30권4호
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    • pp.223-230
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    • 2013
  • Sudden enhancements of daytime NmF2 appeared in Anyang ionosonde data during summer seasons in 2006-2007. In order to investigate the causes of this unusual enhancement, we compared Anyang NmF2's with the total electron contents (GPS TECs) observed at Daejeon, and also with ionosonde data at at mid-latitude stations. First, we found no similar increase in Daejeon GPS TEC when the sudden enhancements of Anyang NmF2 occurred. Second, we investigated NmF2's observed at other ionosonde stations that use the same ionosonde model and auto-scaling program as the Anyang ionosonde. We found similar enhancements of NmF2 at these ionosonde stations. Moreover, the analysis of ionograms from Athens and Rome showed that there were sporadic-E layers with high electron density during the enhancements in NmF2. The auto-scaling program (ARTIST 4.5) used seems to recognize sporadic-E layer echoes as a F2 layer trace, resulting in the erroneous critical frequency of F2 layer (foF2). Other versions of the ARTIST scaling program also seem to produce similar erroneous results. Therefore we conclude that the sudden enhancements of NmF2 in Anyang data were due to the misrecognition of sporadic-E echoes as a F-layer by the auto-scaling program. We also noticed that although the scaling program flagged confidence level (C-level) of an ionogram as uncertain when a sporadic-E layer occurs, it still automatically computed erroneous foF2's. Therefore one should check the confidence level before using long term ionosonde data that were produced by an auto-scaling program.

랜덤포레스트를 이용한 대설피해액에 대한 범주형 예측 및 개선방안 검토 (Categorical Prediction and Improvement Plan of Snow Damage Estimation using Random Forest)

  • 이형주;정건희
    • 한국습지학회지
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    • 제21권2호
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    • pp.157-162
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    • 2019
  • 최근 세계적인 기상이변으로 이례적인 대설과 한파의 발생 빈도가 증가하고 있다. 이로 인해 대설피해 저감에 대한 연구가 진행되고 있으나, 우리나라는 시군구 별 과거 피해이력이 적고, 피해 발생지역과 관측소 간의 거리가 멀어 정확한 피해예측이 어려운 상황이다. 따라서 본 연구에서는 대설피해에 영향을 미친다고 생각되는 인자들의 데이터를 수집한 뒤 랜덤포레스트 모형의 설명변수로 설정하여 추정되는 대설피해액을 범주형태로 예측하고자 하였다. 또한 설명변수 중 취약성 분석을 통해 도출된 취약성 지수를 설명변수로 이용함으로써 지역적 특색과 특성을 반영하였다. 지금은 과거 피해 자료의 부족, 비닐하우스 설계 기준의 변화 등으로 인해 예측 정확도가 높지 않지만, 피해가 발생한 지역의 정확한 기상자료가 확보되고, 변수로 사용한 데이터의 업데이트가 진행된다면 본 연구 결과의 정확도 향상과 재난 발생 전 피해규모 및 범위에 대한 신속한 예측을 통해 대비차원의 재난관리 대처능력이 향상될 것으로 기대된다.

양방향 통신을 지원하는 시분할 기반 무선 센서 네트워크의 구현 (Implementation of a TDMA-based Bidirectional Linear Wireless Sensor Network)

  • 이형봉;박래정;문정호;정태윤
    • 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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    • 제14권4호
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    • pp.341-351
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    • 2008
  • 다수의 센서 노드들이 임의의 장소에 불규칙하게 위치하는 비정형적 환경에서의 무선 센서 네트워크에서는 일반적으로 센서 노드들이 수집한 데이타가 싱크 노드 방향으로만 전송되기 때문에 단방향이라고 할 수 있다. 이런 센서 네트워크에서는 통신이 한쪽 방향으로만 이루어지기 때문에 어떤 특이 데이타가 수신되었을 때 이에 대한 재확인 명령의 전송이 어려우며 따라서 이에 대한 사후 대책 수립이 곤란하다. 이 논문에서는 TDMA에 기반한 단방향 무선 데이타 전송 프로토콜인 WSLP(Wireless Sensor Line Protocol)을 양방향 통신이 가능하도록 확장한 BiWSLP(Biredictional WSLP)를 제안하고 이를 구현한다. 또한 제안한 BiWSLP의 기능을 평가하고 검증하기 위하여, 센서 노드를 통한 데이타 수집뿐만 아니라 노드들에게 명령을 전송하여 노드들의 동작을 제어하는 기능을 가지고 있는 가상 교량 관리 시스템을 구축하고 운영한 결과를 제시한다. 또한 가상 교량 관리 시스템을 운영 결과를 바탕으로 에너지 효율 및 양방향 통신 가능성의 관점에서 BiWSLP의 효용성을 보인다.

한반도의 기후적 요인에 따른 한국 전통 특수의상연구 - 조선시대 기층민 복식을 중심으로 - (A Study on the Traditional Korean Special Costumes in Accordance with Climatic Factors of the Korean Peninsula - Focusing on Costumes of the Commoners in the Joseon Dynasty Period -)

  • 홍보라;간호섭
    • 복식
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    • 제66권3호
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    • pp.107-120
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    • 2016
  • This study examines functions in traditional Korean special costumes in accordance with the climatic factors of the Korean peninsula. The study focused on clothes worn by commoners during the Joseon dynasty. Climate change has been a major global issue in recent times, and it has been a hot topic in social, cultural, scientific, economic, and industrial communities. Studies have been conducted regarding the rapidly changing climate, and finding ways to cope with unusual temperatures. This thesis studies the development of special costumes in preparation for unusual climates, and requirements of the costume in accordance with the climatic factors, as well as the direction of its development. Its biggest significance lies in collecting and organizing the research data on special costume studies, and on costumes of the commoners, which have been fairly insufficient up to this point. After the Little Ice Age, the Joseon Dynasty period faced poor external environment due to unusual temperatures. The results of studying the costumes of the commoners are as follows: The climate of the Korean peninsula displayed different characteristics depending on the season, so the form, material, and appearance of the seasonal clothing items showed clear differences, and the difference in the crops cultivated according to the climate led to difference in material and material preference shown in the costumes. This meant that costumes differed based on region. In addition, difference in social hierarchy, regulations on costume according to class, and farming oriented social background during the period of Joseon dynasty slowed the development of costumes of commoners, but appears to have had a positive effect on the development of special costumes. We anticipate more succeeding studies on costumes of the commoners and special costumes in the future. We hope more costumes that can wisely respond to the approaching changes in temperature in the Korean peninsula can be designed via modernization of traditional Korean special costumes.

척추측만증 환자의 재활 치료 보조기 개발을 위한 구조 해석 모델 제시 (Suggestion of Structural Analysis Model Using Auxiliary Rehabilitation Device for a Patient of Spinal Curvature)

  • 박정일;윤호철;고흥;염덕준;선동윤;김영철
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2009년도 정보 및 제어 심포지움 논문집
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    • pp.141-144
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    • 2009
  • The purpose of this study is to develop the auxiliary rehabilitation device for a patient of spinal curvature. The adolescent diopathic scoliosis(AIS) must be treated by rehabilitation brace if Cobb angle is $20^{\circ}{\sim}40^{\circ}$. The rehabilitation brace is consist of 4 vest and 2 hinge parts(hinge and couple bar) that give a force to the ribs. But thin and light hinge parts for young patient failed easily because of unusual movement of the upper body. We studied optimum design and structural analysis of hinge parts when it distorted by tensile and bending force. The specimen of hinge parts were tested to evaluate the failure strength. And we attached circuits with memory and sensor detecting pressure and displacement to recoding stress in hinge parts. These data are used to alarm the patient to stop unusual movement and understand the load history.

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Specific Recognition of Unusual DNA Structures by Small Molecules: An Equilibrium Binding Study

  • Suh, Dong-Chul
    • BMB Reports
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    • 제29권1호
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    • pp.1-10
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    • 1996
  • The binding interaction of ethidium to a series of synthetic deoxyoligonucleotides containing a B-Z junction between left-handed Z-DNA and right-handed B-DNA, was studied. The series of deoxyoligonucleotides was designed so as to vary a dinucleotide step immediately adjacent to a B-Z junction region. Ethidium binds to the right-handed DNA forms and hybrid B-Z forms which contain a B-Z junction, in a highly cooperative manner. In a series of deoxyoligonucleotides, the binding affinity of ethidium with DNA forms which were initially hybrid B-Z forms shows over an order of magnitude higher than that with any other DNA forms, which were entirely in B-form DNA The cooperativity of binding isotherms were described by an allosteric binding model and by a neighbor exclusion model. The binding data were statistically compared for two models. The conformation of allosterically converted DNA forms under binding with ethidium is found to be different from that of the initial B-form DNA as examined by CD spectra. The ratio of the binding constant was interestingly correlated to the free energy of base unstacking and the conformational conversion of the dinucleotide. The more the base stacking of the dinucleotide is unstable, or the harder the conversion of B to A conformation, the higher the ratio of the binding constant of ethidium with the allosterically converted DNA forms and with the initial B-Z hybrid forms. DNA sequence around a B-Z junction region affects the binding affinity of ethidium. The results in this study demonstrate that ethidium could preferentially interact with unusual DNA structures.

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