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Computer aided analysis system for drilling
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作者 li yanzao china uniuersity of geosciences 《西部探矿工程》 CAS 1995年第5期33-37,共5页
COMPUTERAIDEDANALYSISFORDRILLINGLiYanzaoChinaUniversityofGeosciencesBeijingl00083,ChinaCOMPUTERAIDEDANALYSIS... COMPUTERAIDEDANALYSISFORDRILLINGLiYanzaoChinaUniversityofGeosciencesBeijingl00083,ChinaCOMPUTERAIDEDANALYSISFORDRILLINGLiYanz... 展开更多
关键词 computerIZED analysis system critical BIT WEIGHT and dritical ROTARY speed friction resistance distinguishing formation DISCERNMENT of BIT condition
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Toward Developing a Syllabus-Oriented Computer-Based Question-Banks Software to Support Partially Computerized Exams
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作者 Sulieman Bani-Ahmad 《Journal of Software Engineering and Applications》 2015年第5期252-268,共17页
Aims: This study aims at designing and implementing syllabus-oriented question-bank system that is capable of producing paper-based exams with multiple forms along with answer keys. The developed software tool is nam... Aims: This study aims at designing and implementing syllabus-oriented question-bank system that is capable of producing paper-based exams with multiple forms along with answer keys. The developed software tool is named Χ(Chi)-Pro Milestone and supports four types of questions, namely: Multiple-choice, True/False, Short-Answer and Free-Response Essay questions. The study is motivated by the fact that student number in schools and universities is continuously growing at high, non-linear, and uncontrolled rates. This growth, however, is not accompanied by an equivalent growth of educational resources (mainly: instructors, classrooms, and labs). A direct result of this situation is having relatively large number of students in each classroom. It is observed that providing and using online-examining systems could be intractable and expensive. As an alternative, paper-based exams can be used. One main issue is that manually produced paper-based exams are of low quality because of some human factors such as instability and relatively narrow range of topics [1]. Further, it is observed that instructors usually need to spend a lot of time and energy in composing paper-based exams with multiple forms. Therefore, the use of computers for automatic production of paper-based exams from question banks is becoming more and more important. Methodology: The design and evaluation of X-Pro Milestone are done by considering a basic set of design principles that are based on a list of identified Functional and Non-Functional Requirements. Deriving those requirements is made possible by developing X-Pro Milestone using the Iterative and Incremental model from software engineering domain. Results: We demonstrate that X-Pro Milestone has a number of excellent characteristics compared to the exam-preparation and question banks tools available in market. Some of these characteristics are: ease of use and operation, user-friendly interface and good usability, high security and protection of the question bank-items, high stability, and reliability. Further, X-Pro Milestone makes initiating, maintaining and archiving Question-Banks and produced exams possible. Putting X-Pro Milestone into real use has showed that X-Pro Milestone is easy to be learned and effectively used. We demonstrate that X-Pro Milestone is a cost-effective alternative to online examining systems with more and richer features and with low infrastructure requirements. 展开更多
关键词 Exam Preparation Tools Syllabus-Oriented QUESTION Banks PARTIALLY computerIZED Exams Iterative and Incremental SOFTWARE Development Model X-Pro Milestone
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The computerized LASSI-BC Test versus the Standard LASSI-L Paper-and-Pencil Version in Community-Based-Samples
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作者 Rosie E. Curiel Cid Alexandra Ortega +13 位作者 Ubbo Visser Marcela Kitaigorodsky D. Diane Zheng Diana Hincapie Kirsten Horne Crenshaw Ashleigh Beaulieu Brooke Bosworth Liz Gallardo Emory Neer Sofia Ramirez Elizabeth A. Crocco Mike Georgiou Efrosyni Sfakianaki David A. Loewenstein 《Advances in Alzheimer's Disease》 CAS 2024年第1期11-25,共15页
Proactive Semantic Interference (PSI) and failure to recover from PSI (frPSI), are novel constructs assessed by the LASSI-L. These measures are sensitive to cognitive changes in early Mild Cognitive Impairment (MCI) a... Proactive Semantic Interference (PSI) and failure to recover from PSI (frPSI), are novel constructs assessed by the LASSI-L. These measures are sensitive to cognitive changes in early Mild Cognitive Impairment (MCI) and preclinical AD determined by Aβ load using PET. The goal of this study was to compare a new computerized version of the LASSI-L (LASSI-Brief Computerized) to the standard paper-and-pencil version of the test. In this study, we examined 110 cognitively unimpaired (CU) older adults and 79 with amnestic MCI (aMCI) who were administered the paper-and-pencil form of the LASSI-L. Their performance was compared with 62 CU older adults and 52 aMCI participants examined using the LASSI-BC. After adjustment for covariates (degree of initial learning, sex, education, and language of evaluation) both the standard and computerized versions distinguished between aMCI and CU participants. The performance of CU and aMCI groups using either form was relatively commensurate. Importantly, an optimal combination of Cued B2 recall and Cued B1 intrusions on the LASSI-BC yielded an area under the ROC curve of .927, a sensitivity of 92.3% and specificity of 88.1%, relative to an area under the ROC curve of .815, a sensitivity of 72.5%, and a specificity of 79.1% obtained for the paper-and-pencil LASSI-L. Overall, the LASSI-BC was comparable, and in some ways, superior to the paper-and-pencil LASSI-L. Advantages of the LASSI-BC include a more standardized administration, suitability for remote assessment, and an automated scoring mechanism that can be verified by a built-in audio recording of responses. 展开更多
关键词 Mild Cognitive Impairment Proactive Semantic Interference LASSI-L computerized Cognitive Assessment
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Changes in reaction time, coefficient of variance of reaction time, and autonomic nerve function in the mental fatigue state caused by long-term computerized Kraepelin test workload in healthy volunteers 被引量:1
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作者 Daisuke Kuratsune Seiki Tajima +10 位作者 Junichi Koizumi Kouzi Yamaguti Tetsuya Sasabe Kei Mizuno Masaaki Tanaka Naoko Okawa Hideki Mito Hirokazu Tsubone Yasuyoshi Watanabe Masayasu Inoue Hirohiko Kuratsune 《World Journal of Neuroscience》 2012年第2期113-118,共6页
Fatigue is a common sense caused by crushing labor, stressful social events and various illnesses. It is usually judged by their subjective symptoms, but it should be evaluated in an objective perspective. Here we sho... Fatigue is a common sense caused by crushing labor, stressful social events and various illnesses. It is usually judged by their subjective symptoms, but it should be evaluated in an objective perspective. Here we show that the decrease of working efficiency and sympathetic hyperactivity are associated with mental fatigue state caused by prolonged mental workload. Recently we made a new mental fatigue model of healthy volunteers caused by long-term computerized Kraepelin test (CKT) workload. CKT is our new software for automatically checking the calculation capability, with which it is easy to determine the reaction time (RT), coefficient of variance of reaction time (CV), and accuracy of the answers (AC) during tasks. We put 24 healthy volunteers into the fatigue state by subjecting them to 120 minutes’ CKT workload, and then studied the changes in fatigue sensation, RT, CV, and AC before and after the CKT workload. The fatigue sensation, RT, and CV were clearly increased by the fatigue-inducing task and recovered during the resting period. We also studied the changes in autonomic nerve activity by using heart rate variability analysis. The low/high frequency component ratio (LF/HF) was signifi-cantly increased by the fatigue-inducing task and decreased by resting, suggesting that mental stress causes a relatively sympathetic nerve activity-dominant state. Therefore, our new fatigue model involving a long-term CKT workload is a good mental fatigue model to provide much information about the fatigue state simultane-ously, and the increase of RT, CV, and proportion of sympathetic activity (LF/HF) are associated with mental fatigue state. These might be useful objective biomarkers or evaluating a mental fatigue state. 展开更多
关键词 Fatigue computerIZED Kraepelin Test Reaction Time Accuracy of the ANSWERS AUTONOMIC NERVE Activity
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The Differences of Interstitial Lung Diseases in High-Resolution Computerized Tomography and Pulmonary Function Test among Different Connective Tissue Diseases, and the Correlated Factors 被引量:1
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作者 Zhen Jiang Wenyou Pan +1 位作者 Jinhui Tao Xiangpei Li 《Open Journal of Rheumatology and Autoimmune Diseases》 2018年第2期53-65,共13页
Objective. To study the difference of interstitial lung diseases (ILDs) in high-resolution computerized tomography and pulmonary function test among different connective tissue diseases (CTDs). Methods. 209 patients w... Objective. To study the difference of interstitial lung diseases (ILDs) in high-resolution computerized tomography and pulmonary function test among different connective tissue diseases (CTDs). Methods. 209 patients with different CTDs were recruited and underwent lung HRCT and PFT. Eerythrocyte sedimentation rate (ESR), C-reactive protein (CRP), serum ferritin (SF), anti-SSA, and so on were tested. Based on HRCT, a patient was classified into ILD group (CTD+ILD) or non-ILD group (CTD-ILD). HRCT, PFT, and laboratory markers were compared according to CTDs and CTD-associated ILDs. Results. The incidences of ILD were 79.6%, 82.0%, 89.7%, and 97.1% respectively for Rheumatoid arthritis (RA), primary Sjogren’s symptom (pSS), dermatomyositis/polymyositis (DM/PM), and systemic sclerosis (SSc) groups. RA and pSS patients exhibited more nodules, patching, ground-glass opacity, and cord shadow foci in HRCT, DM/PM and SSc patients exhibited more reticular opacity and honeycombing foci. RA and pSS patients exhibited more obstructive ventilatory disorder, small airway dysfunction and emphysema in PFT, and DM/PM and SSc patients exhibited more restrictive ventilatory disorder, mixed ventilatory disorder. ESR, CRP and SF were significantly higher in total CTD+ILD group than in total CTD-ILD group (P = 0.047, 0.006, 0.004, respectively), and higher in different CTD+ ILD groups than in comparable CTD-ILD groups (P = 0.049, 0.048, and 0.023, pSS+ILD, SSc+ILD and RA+ILD compared to pSS-ILD, SSc-ILD and RA-ILD, respectively for ESR, CRP, SF). The positive rate of anti-SSA was significantly higher in DM/PM+ILD group than in DM/PM-ILD group (P = 0.025). Conclusions. The manifestations and incidences of ILDs differ among different CTDs in HRCT and PFT, and inflammation and anti-SSA are positively correlated with ILDs in different CTDs, which provide important evidences for judging disease condition and prognosis. 展开更多
关键词 CONNECTIVE Tissue Diseases INTERSTITIAL lung Disease HIGH-RESOLUTION computerIZED Tomography PULMONARY Function Test Inflammation
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Designing of A Computerized Cognitive Adaptive Testing Model
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作者 He Lianzhen 《现代外语》 CSSCI 北大核心 1999年第2期169-171,共3页
Therecouldbenoscienceasweknowitwithoutmeasurement.Testing,includingallformsoflanguagetestingandpsychometricsitself,isoneformofmeasurement.Alanguagetestmaybedefinedasaprocedureforelicitinglanguageperformanceandaprocedu... Therecouldbenoscienceasweknowitwithoutmeasurement.Testing,includingallformsoflanguagetestingandpsychometricsitself,isoneformofmeasurement.Alanguagetestmaybedefinedasaprocedureforelicitinglanguageperformanceandaprocedureforassessingthatperformance.How... 展开更多
关键词 Item Response Theory (IRT) computerIZED ADAPTIVE TESTING (CAT ) COGNITIVE PSYCHOLOGY (CP) computerIZED COGNITIVE ADAPTIVE Testing(CCAT)
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Micro-computerized Three-dimensional Reconstruction of the Palmar Arteries and Its Clinical Significance
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作者 张绍祥 何光篪 刘正津 《Journal of Medical Colleges of PLA(China)》 CAS 1990年第3期203-209,共7页
Thirty adult upper extremities were used to study the arteries of the hand byangiography,cross-sectional dissection and three-dimensional reconstruction withmicrocomputer.The arterial skeleton of the palm was composed... Thirty adult upper extremities were used to study the arteries of the hand byangiography,cross-sectional dissection and three-dimensional reconstruction withmicrocomputer.The arterial skeleton of the palm was composed of superficial,deep anddorsal planes.There were three main anastomotic pathways between the radial and ulnararteries or their branches in the radio-ulnar direction,while in the palmar dorsal dirce-tion there were three anastomotic zones between the palrnar and dorsal arterial plancs.The branches of the deep palmar arch radiated distally,proximally,palmarly anddorsally,so that the arch acted as the center of the arterial network of the hand.Thetransverse arterial allocations in the carpo-metacarpal segment of the palm were four intypes,but in the mid-palmar and metacarpo-phalangcal segments were three only.Accord-ing to the sources,cross-sectional area,irrigation territories and anastomoses of the ar-teries in each segment,the clinical significance in the rcplantation of the amputatcd palmshas been 展开更多
关键词 Hand ARTERIES computerS Micro-computerized three dimensional reconstruction REPLANTATION of the PALM
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Multi-slice computerized tomography critical role in transcatheter aortic valve implantation plan: Review of current literature
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作者 Edward Koifman Ashraf Hamdan 《World Journal of Hypertension》 2015年第3期107-114,共8页
Transcatheter aortic valve implantation(TAVI) has been shown in improve outcome of severe aortic stenosis(AS) patients, deemed surgical high-risk or inoperable, and has grown popular in the past decade. The procedure ... Transcatheter aortic valve implantation(TAVI) has been shown in improve outcome of severe aortic stenosis(AS) patients, deemed surgical high-risk or inoperable, and has grown popular in the past decade. The procedure requires accurate prior planning, and demands an integration of a "Heart Team" consisted from cardiac surgeons, interventional cardiologists, and imaging experts. The role of cardiac imaging and especially multi-slice computerized tomography(MSCT) has been a mainstay of pre-evaluation of severe AS patients that allows to accurately depict and size the cardiac and vascular structures, and has become the primary tool for procedural planning. This article is aimed to evaluate current uses of MSCT in severe AS patients undergoing TAVI, delineate the various measurements derived from this modality and review current literature regarding it's advantages over other techniques. 展开更多
关键词 TRANSCATHETER AORTIC valve implantation Multi-slice computerIZED tomography AORTIC ANNULAR sizing Vascular access
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Positron emission tomography/computerized tomography in the evaluation of primary non-Hodgkin's lymphoma of prostate 被引量:4
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作者 Bo Pan Jian-Kui Han +1 位作者 Shi-Cun Wang Ao Xu 《World Journal of Gastroenterology》 SCIE CAS 2013年第39期6699-6702,共4页
Primary malignant lymphoma of the prostate is exceedingly rare.Here we report a case of a 65-year-old man who presented with increased urinary frequency,urinary urgency,and urinary incontinence for two years.Benign pr... Primary malignant lymphoma of the prostate is exceedingly rare.Here we report a case of a 65-year-old man who presented with increased urinary frequency,urinary urgency,and urinary incontinence for two years.Benign prostatic hypertrophy was suspected at primary impression.Ultrasound revealed a hypoechoic lesion of the prostate.The total serum prostate-specific antigen was within normal range.Positron emission tomography/computerized tomography(PET/CT)showed a hypermetabolic prostatic lesion.Prostate biopsy was consistent with a non-germinal center diffuse large B cell lymphoma.There was complete remission of the prostatic lesion following six cycles of chemotherapy as shown on the second PET/CT imaging.18F-fluoro-deoxy glucose PET/CT is not only a complement to conventional imaging,but also plays a significant role in the diagnosis and evaluation of treatment response of prostatic lymphoma. 展开更多
关键词 Fluoro-Deoxy-Glucose Positron emission tomography/computerized tomography Non-Hodgkins LYMPHOMA PROSTATIC LYMPHOMA EVALUATION
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Computer-Aided Solution to the Vibrational Effect of Instabilities in Gas Turbine Compressors 被引量:1
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作者 Ezenwa Alfred Ogbonnaya Hyginus Ubabuike Ugwu Charles Agbeju Nimibofa Johnson 《Engineering(科研)》 2010年第8期658-664,共7页
Surge and stall are the two main types of instabilities that often occur on the compressor system of gas turbines. The effect of this instability often leads to excessive vibration due to the back pressure imposed to ... Surge and stall are the two main types of instabilities that often occur on the compressor system of gas turbines. The effect of this instability often leads to excessive vibration due to the back pressure imposed to the system by this phenomenon. In this work, fouling was observed as the major cause of the compressor instability. A step to analyze how this phenomenon can be controlled with the continuous examination of the vibration amplitude using a computer approach led to the execution of this work. The forces resulting to vibration in the system is usually external to it. This external force is aerodynamic and the effect was modeled using force damped vibration analysis. A gas turbine plant on industrial duty for electricity generation was used to actualize this research. The data for amplitude of vibration varied between -15 and 15 mm/s while the given mass flow rate and pressure ratio were determined as falling between 6.1 to 6.8 kg/s and 9.3 to 9.6 respectively. A computer program named VICOMS written in C++ programming language was developed. The results show that the machine should not be run beyond 14.0 mm vibration amplitude in order to avoid surge, stall and other flow-induced catastrophic breakdown. 展开更多
关键词 computerIZED Solution INSTABILITIES VIBRATION Gas TURBINE Compressors OPERATIONAL Limits
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RompecPC: A computerized program to create and solve jigsaw puzzles
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作者 Miguel Angel Guevara Marai Pérez Hernández +2 位作者 Marisela Hernández González Araceli Sanz-Martin Sonia Ramírez Zapata 《Journal of Biomedical Science and Engineering》 2013年第7期717-721,共5页
RompecPC is a computerized program designed to create and assemble jigsaw puzzles. The program automatically records the solver’s responses as the number of pieces positioned correctly, the number of correct and inco... RompecPC is a computerized program designed to create and assemble jigsaw puzzles. The program automatically records the solver’s responses as the number of pieces positioned correctly, the number of correct and incorrect movements, the number of times that she/he attempts to move a piece to the same place (perseverations), and the latency and place to which each piece is moved or attempted to be moved. These features facilitate the implementation and evaluation of puzzles while also reducing human error. Therefore, RompePC is a useful tool for the neuropsychological assessment of visuospatial skills in both clinical and experimental research. 展开更多
关键词 computerIZED Testing NEUROPSYCHOLOGICAL Test JIGSAW PUZZLES VISUOSPATIAL ABILITIES
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Applied Strain Field on Microstructure Optimization of Ti-Al-Nb Alloy Computer Simulated by Phase Field Approach 被引量:3
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作者 Wei GUO Yaping ZONG +1 位作者 Gang WANG Liang ZUO Department of Materials Science and Engineeing,Northeastern University,Shenyang 110004, China 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2004年第3期245-248,共4页
The effects of applied tensile strain on the coherent α_2→O-phase transformation in Ti-Al-Nb alloys are explored bycomputer simulation using a phase-field method. The focus is on the influence of the applied strain ... The effects of applied tensile strain on the coherent α_2→O-phase transformation in Ti-Al-Nb alloys are explored bycomputer simulation using a phase-field method. The focus is on the influence of the applied strain direction onthe microstructure and volume fraction of the O-phase precipitates. It is found that altering applied strain directioncan modify microstructure of Ti-25Al-10~12Nb (at. pct) alloy during α_2→O-phase transformation effectively andfull laminate microstructure in the Ti-25Al-10Nb (at. pct) alloy can be realized by an applied strain only along thedirection 30°away from the α_2 phase <1010> in magnitude equivalent to the stress-free transformation strain. Thesimulation also shows that not only the magnitude of applied strain but also the applied strain direction influencesthe O-phase volume fraction and the effect of strain direction on the volume fraction is up to 25%. 展开更多
关键词 Phase field simulation Strain induced phase transformation Ti-Al-Nb alloy computerization materials Microstructure evoutionv Precipitates geometry Microstructure design
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Effects of Irregular Respiratory Motion on the Positioning Accuracy of Moving Target with Free Breathing Cone-Beam Computerized Tomography 被引量:1
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作者 Xiang Li Tianfang Li +9 位作者 Ellen Yorke Gig Mageras Xiaoli Tang Maria Chan Weijun Xiong Marsha Reyngold Richard Gewanter Abraham Wu John Cuaron Margie Hunt 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2018年第2期173-183,共11页
For positioning a moving target, a maximum intensity projection (MIP) or average intensity projection (AIP) image derived from 4DCT is often used as the reference image which is matched to free breathing cone-beam CT ... For positioning a moving target, a maximum intensity projection (MIP) or average intensity projection (AIP) image derived from 4DCT is often used as the reference image which is matched to free breathing cone-beam CT (FBCBCT) before treatment. This method can be highly accurate if the respiratory motion of the patient is stable. However, a patient’s breathing pattern is often irregular. The purpose of this study is to investigate the effects of irregular respiration on positioning accuracy for a moving target aligned with FBCBCT. Nine patients’ respiratory motion curves were selected to drive a Quasar motion phantom with one embedded cubic and two spherical targets. A 4DCT of the phantom was acquired on a CT scanner (Philips Brilliance 16) equipped with a Varian RPM system. The phase binned 4DCT images and the corresponding MIP and AIP images were transferred into Eclipse for analysis. FBCBCTs of the phantom driven by the same respiratory curves were also acquired on a Varian TrueBeam and fused such that both CBCT and MIP/AIP images share the same target zero positions. The sphere and cube volumes and centroid differences (alignment error) determined by MIP, AIP and FBCBCT images were calculated, respectively. Compared to the volume determined by MIP, the volumes of the cube, large sphere, and small sphere in AIP and FBCBCT images were smaller. The alignment errors for the cube, large sphere and small sphere with center to center matches between MIP and FBCBCT were 2.5 ± 1.8 mm, 2.4 ± 2.1 mm, and 3.8 ± 2.8 mm, and the alignment errors between AIP and FBCBCT were 0.5 ± 1.1 mm, 0.3 ± 0.8 mm, and 1.8 ± 2.0 mm, respectively. AIP images appear to be superior reference images to MIP images. However, irregular respiratory pattern could compromise the positioning accuracy, especially for smaller targets. 展开更多
关键词 CONE Beam computerIZED TOMOGRAPHY RESPIRATORY Motion Effect
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A computerized resolution visual acuity test in preschool and school age children
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作者 Ying-Yan Qin Zhen-Zhen Liu +5 位作者 Li-Yuan Zhu Xuan Bao Fu-Rong Luo Yi-Zhi Liu Young Tsau Ming-Xing Wu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2020年第2期284-291,共8页
●AIM:To develop a novel approach called the Autoacuity Tester,and to evaluate its validity,especially the sensitivity and specificity for detecting amblyopia.●METHODS:Children aged from 3 to 12 y(n=552)were enrolled... ●AIM:To develop a novel approach called the Autoacuity Tester,and to evaluate its validity,especially the sensitivity and specificity for detecting amblyopia.●METHODS:Children aged from 3 to 12 y(n=552)were enrolled in the study.The validity of the Autoacuity Tester was evaluated by comparing it to the Tumbling E Early Treatment Diabetic Retinopathy Study(ETDRS)acuity chart for school age children,and Lea Symbols and Teller acuity card(TAC)for preschool children.The repeatability was assessed by coefficient of repeatability(COR).The sensitivity and specificity for detecting amblyopia were calculated.●RESULTS:The mean difference(95%limits of agreement)between the Autoacuity Tester and the ETDRS tests were-0.03(-0.24,0.19)logMAR for the school age group.In preschool children,the mean difference was 0.04(-0.14,0.21)logMAR between the Autoacuity Tester and the TAC and 0.00(-0.17,0.18)logMAR between the Autoacuity Tester and the Lea Symbols.For the school age group,the COR was 0.20 logMAR for the Autoacuity Tester and 0.18 logMAR for the ETDRS.For the preschool group,the COR was 0.13 logMAR for the Autoacuity Tester and 0.21 logMAR for TAC.The Autoacuity Tester(88%)is more sensitive than TAC(72%)in detecting amblyopia(P=0.04),while had similar specificity(92%vs 90%,P=0.20).●CONCLUSION:The Autoacuity Tester provides a reliable alternative for assessing visual acuity,and offers advantage of higher testability and repeatability for preschool children. 展开更多
关键词 visual ACUITY TEST computerIZED CHILDREN sensitivity AMBLYOPIA
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Screening for lung cancer with chest computerized tomography: Is it cost efficient?
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作者 Tomasz Jaroslaw Szczesny Malgorzata Kanarkiewicz Janusz Kowalewski 《World Journal of Respirology》 2015年第2期160-165,共6页
Despite lung cancer(LC) screening by low-dose computerized tomography(LDCT) gaining many proponents worldwide, for many years it was not recognized as a life-prolonging and cost-effective procedure, until recently. Pr... Despite lung cancer(LC) screening by low-dose computerized tomography(LDCT) gaining many proponents worldwide, for many years it was not recognized as a life-prolonging and cost-effective procedure, until recently. Prospective observational studies had not been able to prove that this screening prolongs survival, but they helped to specify the inclusion and exclusion criteria. Long-awaited results of a prospective, randomized trial finally provided the evidence that LC screening with LDCT can prolong survival of the screened population. Several costeffectiveness analyses were performed to justify mass introduction of this screening. Results of these analyses are equivocal, although conclusions highly depend upon inclusion and exclusion criteria, methods of analysis and prices of medical procedures which differ between countries as well as the incidence of other pulmonary nodules, especially tuberculosis. Therefore, costeffectiveness analysis should be performed separately for every country. Cost-effectiveness depends especially upon the rate of false-positive results and the rate of unnecessary diagnostic, screening and treatment procedures. To ensure high cost-effectiveness, LC screening should be performed in accordance with screening protocol, in dedicated screening centers equipped with nodule volume change analysis, or as a prospective non-randomized trial, to ensure compliance with the inclusion and exclusion criteria. To ensure high cost-effectiveness of LC screening, future research should concentrate on determination of highrisk groups and further specifying the inclusion and exclusion criteria. 展开更多
关键词 Lung cancer Non-small cell lung cancers SCREENING COST-EFFECTIVENESS computerized tomography Low-dose computerized tomography
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Peripancreatic collections in acute pancreatitis: Correlation between computerized tomography and operative fi ndings 被引量:5
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作者 Santhi Swaroop Vege Joel G Fletcher +1 位作者 Rupjyoti Talukdar Michael G Sarr 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第34期4291-4296,共6页
AIM: To evaluate the ability of contrast-enhanced computerized tomography (CECT) to characterize the nature of peripancreatic collections.METHODS: Twenty five patients with peripancreatic collections on CECT and who u... AIM: To evaluate the ability of contrast-enhanced computerized tomography (CECT) to characterize the nature of peripancreatic collections.METHODS: Twenty five patients with peripancreatic collections on CECT and who underwent operative intervention for severe acute pancreatitis were retrospectively studied. The collections were classified into (1) necrosis without frank pus; (2) necrosis with pus; and (3) fluid without necrosis. A blinded radiologist assessed the preoperative CTs of each patient for necrosis and peripancreatic fluid collections. Peripancreatic collections were described in terms of volume, location, number, heterogeneity, fluid attenuation, wall perceptibility, wall enhancement, presence of extraluminal gas, and vascular compromise.RESULTS: Fifty-four collections were identif ied at operation, of which 45 (83%) were identif ied on CECT. Of these, 25/26 (96%) had necrosis without pus, 16/19 (84%) had necrosis with pus, and 4/9 (44%) had fluid without necrosis. Among the study characteristics, fluid heterogeneity was seen in a greater proportion of collections in the group with necrosis and pus, compared to the other two groups (94% vs 48% and 25%, P = 0.002 and 0.003, respectively). Among the wall characteristics, irregularity was seen in a greater proportion of collections in the groups with necrosis with and without pus, when compared to the group with fluid without necrosis (88% and 71% vs 25%, P = 0.06 and P < 0.01, respectively). The combination of heterogeneity and presence of extraluminal gas had a specif icity and positive likelihood ratio of 92% and 5.9, respectively, in detecting pus. CONCLUSION: Most of the peripancreatic collections seen on CECT in patients with severe acute pancreatitis who require operative intervention contain necrotic tissue. CECT has a somewhat limited role in differentiating the different types of collections. 展开更多
关键词 Contrastenhanced computerized tomogra-phy CORRELATION Pancreatic necrosis PANCREATITIS Peripancreatic fluid collection Surgery
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COMPUTER SIMULATION OF DIRECT TORQUE CONTROL SYSTEM
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作者 Hu Yuwen Xu Yue(Department of Automatic Control,NUAA 29 Yudao Street,Nanjing 210016,P.R.China) 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1994年第2期189-193,共5页
Computer simulation researches on Direct Torque Control System (DTC) are to be done. That fact is demonstrated:at high speed,the operating property of an induction motor is very good,almost the same as fieldoriented c... Computer simulation researches on Direct Torque Control System (DTC) are to be done. That fact is demonstrated:at high speed,the operating property of an induction motor is very good,almost the same as fieldoriented control system fat low speed (for example: below 2-3Hz), the operating property of a motor is getting worse,and the stator resistance R1 of the motor must be compensated. If compensation precision gets 5 %,the operating property of the motor will be greatly improved. 展开更多
关键词 computerIZED SIMULATION SPEED CONTROL SYSTEM motors
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Computerized image in automatic recognition of micronuclei of bi-nucleated lymphocytes
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作者 易东 李辉智 《Journal of Medical Colleges of PLA(China)》 CAS 1998年第4期313-315,共3页
To put forward a method of automatic recognition of the micronuclei on computerized image in bi-nucleated lymphocytes. Methods: The procedure was as the follows: ① The nuclei and cytoplasm images were automatically e... To put forward a method of automatic recognition of the micronuclei on computerized image in bi-nucleated lymphocytes. Methods: The procedure was as the follows: ① The nuclei and cytoplasm images were automatically extracted from the background in order that the nuclei and cytoplasm images could be preprocessed individually.② Noise in two images was reduced, the edges in the nuclei image smoothed and then the big-point noise in the cytoplasm image taken off. ③ The nuclei was identified and the single cytoplasm acquired individually form nuclei and cytoplasm image. ④ The two preprocessed images were put together to identify the bi-nuclei and micronuclei form the overlapped map. Results: Many new models for image processing have been established. Preliminary measurement showed that the accuracy of recognition reached a high percentage of 85%. Conclusion: It is of great value to put the automatic recognition system into use. 展开更多
关键词 bi-nucleated LYMPHOCYTE micronuclei computerIZED IMAGE automatic RECOGNITION
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胃肠道间质瘤的CT诊断价值 被引量:4
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作者 董其龙 胡绍童 皮厚山 《临床军医杂志》 CAS 2010年第4期622-624,F0004,共4页
目的分析胃肠道间质瘤的CT表现,并与病理结果对照,旨在提高诊断的准确性。方法回顾性分析经手术和病理证实的32例胃肠道间质瘤患者的影像资料。结果 32例肿瘤均为单发,良性5例,潜在恶性10例,恶性17例。CT表现:黏膜下富血供性肿块,形态... 目的分析胃肠道间质瘤的CT表现,并与病理结果对照,旨在提高诊断的准确性。方法回顾性分析经手术和病理证实的32例胃肠道间质瘤患者的影像资料。结果 32例肿瘤均为单发,良性5例,潜在恶性10例,恶性17例。CT表现:黏膜下富血供性肿块,形态类圆形或不规则,可有囊变、坏死、出血、钙化。增强后良性者强化均匀,边界清楚,恶性及潜在恶性者强化不均匀,可有邻近结构侵犯。结论 CT能较好的显示肿瘤的内部结构、明确肿瘤的范围,有助于该病的鉴别诊断、指导制订治疗方案、检出远处转移和评价治疗效果。 展开更多
关键词 GASTROINTESTINAL STROMAL Tumor
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AN ANALYSIS OF ACOUSTIC CHARACTERISTICS OFCLEFT PALATE SPEECH WITH COMPUTERIZED SPEECH SIGNAL PROCESSING SYSTEM 被引量:1
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作者 李锦峰 刘建华 《Journal of Pharmaceutical Analysis》 CAS 1996年第2期162-165,共4页
The acoustic characteristics or the chinese vowels of 24 children with cleft palate and 10 normal control children were analyzed by computerized speech signal processing system (CSSPS),and the speech articulation was ... The acoustic characteristics or the chinese vowels of 24 children with cleft palate and 10 normal control children were analyzed by computerized speech signal processing system (CSSPS),and the speech articulation was judged with Glossary of clert palate speech(GCPS).The listening judgement showed that the speech articulation was significantly different between the two groups(P<0.01).The objective quantitative measurement suggested that the formant pattern(FP)of vowels in children with cleft palate was different from that of normal control children except vowel[a](P< 0.05).The acoustic vowelgraph or the Chinese vowels which demonstrated directly the relationship of vocal space and speech perception was stated with the first formant frequence(F1)and the second formant frequence(F2).The authors conclude that the values or F1 and F2 point out the upward and backward tongue movement to close the clert, which reflects the vocal characteristics of trausmission of clert palate speech. 展开更多
关键词 cleft palate speech the Chinese vowels the formant pattern the speech articulation computerized speech singnal processing system
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