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BUBBLE BEHAVIORS IN A SLOWLY ROTATING HELIUM DEWAR IN A GRAVITY PROBE-B SPACECRAFT EXPERIMENT

JOURNAL OF SPACECRAFT AND ROCKETS 1989年第3期26卷 167-172页

作者： HUNG, RJ TSAO, YD HONG, BB LESLIE, FW NASA GEORGE C MARSHALL SPACE FLIGHT CTRDEPT MECH ENGNHUNTSVILLEAL 35812

Potential problems for the Gravity Probe-B (GP-B) spacecraft design requirements and the operational considerations could arise because of the free surface configurations between liquid helium and helium vapor in the rotating dewar. This free surface is present in the partially filled liquid helium dewar. The liquid helium in the dewar is depleted as it is consumed as propellant for the spacecraft. In this study, the doughnut- shaped helium bubble equilibrium profiles in the rotating dewar have been numerically calculated. These calculations were performed under the conditions imposed during the period of the GP-B experiment instrument calibration (gyro spinup period) and also during the normal operational stages of the GP-B spacecraft. (Author)

关键词： Spacecrafts Propellant Spacecraft Design Microgravity Surface Tension Cylindrical Coordinate System Navier Stokes Equations computer algorithm Fluid Mechanics Convection

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Connection between urban heat island and sky view factor approximated by a software tool on a 3D urban database

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INTERNATIONAL JOURNAL OF ENVIRONMENT AND POLLUTION 2009年第1-3期36卷 59-80页

作者： Unger, Janos Univ Szeged Dept Climatol & Landscape Ecol H-6701 Szeged Hungary

This study provides a review on methods of Sky View Factor (SVF) determination and intra-urban surface geometry-air temperature relationship. Then, a software-based method of SVF estimation from a 3D database, describing urban surface elements, is applied. Finally, related investigations in Szeged and importance of the results obtained are discussed. Previous investigations were limited to only specific urban parts or some canyons and used small numbers of sites and few occasions of measurements. This study utilises a large number of areal means of SVF and temperature related to a large sample area and based on numerous measurements. Our investigation reveals a strong relationship between these variables. Thus, surface geometry is a significant determining factor of the temperature distribution if the selected scale is appropriate. Therefore, investigations of sufficient number of appropriate-sized areas, covering large parts of a city, are needed to draw well-established conclusions on the studied relationship.

关键词： 3D urban database sample area SVF sky view factor computer algorithm UHI urban heat island linear regression Szeged Hungary

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SEARCHING OPTIMAL DESIGNS IN THE PRESENCE OF SERIALLY CORRELATED ERRORS

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BIOMETRICAL JOURNAL 1988年第5期30卷 615-625页

作者： ZERGAW, G UNIV KENT SCH MATH STUDIES DEPT STAT CANTERBURY CT2 7NF KENT ENGLAND

Based on simple updating formulae, a computer algorithm for searching optimal designs when the errors are believed to be serially correlated in the one-dimensional situation is described. The performance of the design... 详细信息

关键词： computer algorithm Grow Neighbour‐Count matrix Optimal criterion Optimal design Seed design Serial Correlation Squeeze

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NOVEL NONITERATIVE LOAD FLOW FOR VOLTAGE CONTINGENCY ANALYSIS

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INTERNATIONAL JOURNAL OF ELECTRICAL POWER & ENERGY SYSTEMS 1994年第1期16卷 11-16页

作者： SINGH, SN KALRA, PK SRIVASTAVA, SC UPSEB Study Cell IIT Kanpur India Department of Electrical Engineering IIT Kanpur India

This paper reports on the development of new linearized AC load flow models based on a novel approach. The load flow models have been developed based on the principle of linearizing nonlinear power flow equations around complete operating range by minimizing the square and integral square errors. The new methods involve the direct solution of linear simultaneous power flow equations and thus are non-iterative in nature. The performance of the proposed linearized models have been tested on IEEE 14-bus and IEEE 30-bus systems and an 89-bus Indian system for analysing both a base case and contingency cases. Their results are compared with the exact load flow and some of the existing approximate load flow solutions. The proposed linearized load flow models are found to be extremely fast and much more accurate, especially for voltage magnitude prediction, than other existing linearized and approximate models. It is envisaged that the new models have great potential for on-line applications in power system studies and contingency simulation for voltage security evaluation.

关键词： LINEARIZED LOAD FLOW CONTINGENCY ANALYSIS VOLTAGE SECURITY REAL-TIME APPLICATIONS computer algorithm

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Incidence rates of hospital-acquired urinary tract and bloodstream infections generated by automated compilation of electronically available healthcare data

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JOURNAL OF HOSPITAL INFECTION 2015年第3期91卷 231-236页

作者： Redder, J. D. Leth, R. A. Moller, J. K. Lillebaelt Hosp Dept Clin Microbiol DK-7100 Vejle Denmark Univ So Denmark Inst Reg Hlth Res Odense Denmark Aarhus Univ Hosp Dept Clin Microbiol Aarhus Denmark

Background: Monitoring of hospital-acquired infection (HAI) by automated compilation of registry data may address the disadvantages of laborious, costly and potentially subjective and often random sampling of data by manual surveillance. Aim: To evaluate a system for automated monitoring of hospital-acquired urinary tract (HA-UTI) and bloodstream infections (HA-BSI) and to report incidence rates over a five-year period in a Danish hospital trust. Methods: Based primarily on electronically available data relating to microbiology results and antibiotic prescriptions, the automated monitoring of HA-UTIs and HA-BSIs was validated against data from six previous point-prevalence surveys (PPS) from 2010 to 2013 and data from a manual assessment (HA-UTI only) of one department of internal medicine from January 2010. Incidence rates (infections per 1000 bed-days) from 2010 to 2014 were calculated. Findings: Compared with the PPSs, the automated monitoring showed a sensitivity of 88% in detecting UTI in general, 78% in detecting HA-UTI, and 100% in detecting BSI in general. The monthly incidence rates varied between 4.14 and 6.61 per 1000 bed-days for HA-UTI and between 0.09 and 1.25 per 1000 bed-days for HA-BSI. Conclusion: Replacing PPSs with automated monitoring of HAIs may provide better and more objective data and constitute a promising foundation for individual patient risk analyses and epidemiological studies. Automated monitoring may be universally applicable in hospitals with electronic databases comprising microbiological findings, admission data, and antibiotic prescriptions. (C) 2015 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

关键词： Bloodstream infection computer algorithm Electronic registry Healthcare data Hospital-acquired infection Urinary tract infection

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Morphological Classification of the Zygomatic Regions in Young Chinese Han Males and Females Based on a Simulated Moire Pattern

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FACIAL PLASTIC SURGERY 2020年第3期36卷 281-289页

作者： Wang, Guanhuier Chen, Lujia Feng, Ning Wu, Siqiao Zhao, Jianfang Li, Dong Peking Univ Third Hosp Dept Plast & Reconstruct Surg 49 Huayuan Rd Beijing 100191 Peoples R China

The complex curved contours of the zygomatic regions are difficult to analyze. Therefore, a better evaluation medium must be developed. We aimed to examine and summarize the morphological characteristics of the zygomatic region by using a moire pattern map and computer algorithm. In this cross-sectional study, we collected three-dimensional images of the facial contours of 251 Han Chinese youth and established a morphological moire map database. Clustering analysis using a computer algorithm was applied to obtain the zygomatic morphologies for classification. Aesthetic evaluation was performed to summarize the characteristics of the zygomatic types and provide reference for the preoperative morphological design of the midface. Zygomatic regions were morphologically classified into five types. Each type had its typical feature in the moire pattern map. The moire stripes in the left zygomatic region formed an "omega" shape outward and downward in type 1, and they tended to be diagonal like "\\\" in type 2, smoothly curved like ")))" in type 3, vertical like "|||" in type 4, and diagonal like "///" in type 5. The aesthetic evaluation outcome indicated that the integrally flat zygoma (type 4) was more aesthetically pleasing among males, and the integrally prominent zygoma (type 3) was more aesthetically pleasing among females. Five morphological contour types of the zygoma were classified among the Chinese Han males and females based on the simulated moire pattern. This morphological classification would aid in preparing a guide for clinical diagnosis and surgical planning.

关键词： three-dimensional anthropometry zygomatic moire pattern computer algorithm

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Measuring optimal connections in large networks: A new algorithm and its applications

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JOURNAL OF MATHEMATICAL SOCIOLOGY 2004年第3期28卷 197-213页

作者： Yang, S Hexmoor, H Univ Arkansas Dept Sociol Fayetteville AR 72701 USA Univ Arkansas Dept Comp Sci & Engn Fayetteville AR 72701 USA

Researchers have identified several problems in measuring the strongest path connecting pairs of actors in valued graphs. To address these problems, it has been proposed that average path value be used to indicate optimal connections between dyads. However, a lack of proper computer algorithm and its implementation has hindered a wide-range application of the proposed solution. In this paper we develop a computer algorithm and fully implement it with four JAVA programs, which are available on request. These programs produce an optimal connection matrix, which is subsequently inputted into UCINET for further multidimensional scaling and clustering analysis. We demonstrate this procedure with a data matrix containing 38 organizations in information technology. We discuss the methodological implications of the application of our algorithm to future social network studies.

关键词： graph theory average path value computer algorithm valued graph

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CLINICAL MEASUREMENTS OF PERIODONTITIS

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JOURNAL OF CLINICAL PERIODONTOLOGY 1986年第5期13卷 446-455页

作者： GOODSON, JM Department of Pharmacology Forsyth Dental Center Boston MA USA

Clinical measurement of periodontitis has historically focused on the concept of periodontitis as a slow, continuous process which has emphasized measurements of the static condition of periodontal pockets. Observations based on longitudinal measurement of attachment loss in untreated subjects have indicated that periodontal destruction occurs in discrete episodes of short duration. Based on these studies, it has been suggested that chronic periodontal disease proceeds through a series of random episodic attacks. Periodontal sites are considered as existing in 2 states, either disease active or inactive. During periods of disease activity, sites increase in their probeable depth, whereas during the inactive state, no significant change in probing depth can be detected. The detection of changes at periodontal sites from time series data has been addressed by 3 analytical procedures: regression, running medians, and tolerance. The standard deviation of differences between replicate measurements of 48, 064 sites for 56 subjects was 0.7727 mm. From this estimate, the computed standard deviation for a single measurement was 0.5464 mm and for the mean of 2 measurements was 0.386 mm. The expected error rates of each method have been estimated by computer simulation. The type‐I error for the regression (p=0.028), running median (p=0.000025), and tolerance (p=0.00012) methods were all sufficiently low to consider it unlikely that reported observations could be accounted for by methodologic error. The estimated type‐II error for the regression (p=0.446), running median p=0.152), and tolerance p=0.068) methods suggests that a substantial fraction of disease active sites was not detected by these methods. Several data set properties have been investigated. Intraclass correlation coefficients were computed from attachment level changes on 8,130 sites in 105 patients. By this analysis, 7% of the variation was associated with the subject and 93.3% with the individual sites, indica

关键词： Attachment level attachment loss attachment gain autocorrelation computer algorithm

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Comparison of QT Correction Methods in the Pediatric Population of a Community Hospital: A Retrospective Study

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Congenital Heart Disease 2024年第1期19卷 107-121页

作者： Koren Hyogene Kwag Ibrahim Kak Ying Li Walid Khass Alec McKechnie Oksana Nulman Brande Brown Manoj Chhabra Department of Pediatrics New York Presbyterian Brooklyn Methodist HospitalBrooklyn11215USA Department of Population Health Sciences Division of BiostatisticsWeill Cornell MedicineNew York10065USA

Objective:Accurate measurement of QT interval,the ventricular action potential from depolarization to repolarization,is important for the early detection of Long QT *** most effective QT correction(QTc)formula has yet to be determined in the pediatric population,although it has intrinsically greater extremes in heart rate(HR)and is more susceptible to errors in *** authors of this study compare six dif-ferent QTc methods(Bazett,Fridericia,Framingham,Hodges,Rautaharju,and a computer algorithm utilizing the Bazett formula)for consistency against variations in HR and RR ***:Descriptive Retrospective *** included participants from a pediatric cardiology practice of a community hospital who had an ECG performed in *** participants were healthy patients with no past medical history and no regular ***:ECGs from 95 participants from one month to 21 years of age(mean 9.7 years)were included with a mean HR of 91 beats per minute(bpm).The two-sample paired t-test or Wilcoxon signed-rank test assessed for any difference between QTc methods.A statistically signiﬁcant difference was observed between every combination of two QTc *** Spearman’s rank correlation analysis explored the QTc/HR and QTc/RR relationships for each *** method was most independent of HR and RR with the lowest absolute value of correlation coefﬁ*** and computer had moderate correlations,while Framingham and Rautaharju exhibited strong *** were positive for Bazett and computer,reﬂecting results from prior studies demonstrating an over-correction of Bazett at higher *** the linear QTc/HR regression analysis,Bazett had the slope closest to zero,although computer,Hodges,and Fridericia had comparable ***,Fridericia had the linear QTc/RR regression coefﬁcient closest to *** Bland-Altman method assessed for bias and the limits of agreement between correction *** an

关键词： Corrected QT interval QT prolongation long QT syndrome electrocardiogram retrospective study bazett fridericia framingham hodges rautaharju computer algorithm

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A DATABASE OF PROTEIN-STRUCTURE FAMILIES WITH COMMON FOLDING MOTIFS

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PROTEIN SCIENCE 1992年第12期1卷 1691-1698页

作者： HOLM, L OUZOUNIS, C SANDER, C TUPAREV, G VRIEND, G European Molecular Biology Laboratory Heidelberg Germany.

The availability of fast and robust algorithms for protein structure comparison provides an opportunity to produce a database of three-dimensional comparisons, called families of structurally similar proteins (FSSP). The database currently contains an extended structural family for each of 154 representative (below 30% sequence identity) protein chains. Each data set contains: the search structure;all its relatives with 70-30% sequence identity, aligned structurally;and all other proteins from the representative set that contain substructures significantly similar to the search structure. Very close relatives (above 700% sequence identity) rarely have significant structural differences and are excluded. The alignments of remote relatives are the result of pairwise all-against-all structural comparisons in the set of 154 representative protein chains. The comparisons were carried out with each of three novel automatic algorithms that cover different aspects of protein structure similarity. The user of the database has the choice between strict rigid-body comparisons and comparisons that take into account interdomain motion or geometrical distortions;and, between comparisons that require strictly sequential ordering of segments and comparisons, which allow altered topology of loop connections or chain reversals. The data sets report the structurally equivalent residues in the form of a multiple alignment and as a list of matching fragments to facilitate inspection by three-dimensional graphics. If substructures are ignored, the result is a database of structure alignments of full-length proteins, including those in the twilight zone of sequence similarity. The database makes explicitly visible architectural similarities in the known part of the universe of protein folds and may be useful for understanding protein folding and for extracting structural modules for protein design. The data sets are available via Internet.

关键词： computer algorithm MODULAR PROTEIN DESIGN PROTEIN FOLDING PROTEIN STRUCTURE ALIGNMENT PROTEIN STRUCTURE DATABASE

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