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91.
92.
EL Lee MJ Robinson ML Thong SD Puthucheary TH Ong KK Ng 《Canadian Metallurgical Quarterly》1977,91(6):991-995
All of 16 infants with neonatal meningitis treated during a 30-month period were found to have accompanying ventriculitis at the time of the initial ventricular puncture. Fifteen of these infants were caused by gramm-negative organisms. All infants received antibiotics systemically and intraventricularly via an implanted ventriculostomy reservoir or by direct ventricular injection. Antibiotic concentrations within the ventricular fluid were monitored during chemotherapy; the complications encountered during treatment are discussed. Fifteen infants survived the infection; of these, seven infants were normal at follow-up examinations. In our experience intraventricular chemotherapy as an adjunct to systemic administration of antibiotics has greatly reduced the mortality rate in neonatal meningitis. 相似文献
93.
MA Dejun Chung Wo Ong LIU Jianmin & HE Jiawen . Surface Engineering Research Institute CMES Beijing China . Department of Applied Physics Materials Research Center The Hong Kong Polytechnic University Hong Kong China . State Key Laboratory for Mechanical Behavior of Materials Xian Jiaotong University Xian China 《中国科学E辑(英文版)》2004,47(4):398-408
Loadanddepthsensingindentationtechniqueisveryusefulinprobingthemechanicalpropertiesofmaterialsonsmallscales[1—5].Youngsmodulusisoneofthemostcommonlyconcernedmaterialpropertiesmeasuredbythiskindoftechnique.Conventionally,itisachievedonthebasisofthemethodproposedbyOliverandPharr[4]usingthewell-knownrelationship:whereSuistheinitialslopeofunloadingcurve,EristhereducedmodulusandrelatedwiththeYoungsmodulusEandPoissonsratioνoftheindentedmaterialandthose(Ei,ni)oftheindenterbytheequation1/Er=(1-n2… 相似文献
94.
The effects of Ni(II) in a synthetic wastewater on the activity of activated sludge microorganisms and sequencing batch reactor (SBR) treatment process were investigated. Two parallel lab-scale SBR systems were operated. One was used as a control unit, while the other received Ni(II) concentrations equal to 5 and 10 mg/l. The SBR systems were operated with FILL, REACT, SETTLE, DRAW and IDLE modes in the time ratio of 0.5:3.5:1.0:0.75:0.25 for a cycle time of 6 h. The addition of Ni(II) into SBR system caused drastically dropped in TOC removal rate (k) and specific oxygen uptake rate (SOUR) by activated sludge microorganisms due to the inhibitory effects of Ni(II) on the bioactivity of microorganisms. The addition of 5 mg/l Ni(II) caused a slight reduction in TOC removal efficiency, whereas 10 mg/l Ni(II) addition significantly affected the SBR performance in terms of suspended solids and TOC removal efficiency. Termination of Ni(II) addition led to almost full recovery of the bioactivity in microorganisms as shown in the increase of specific oxygen uptake rate (SOUR) and SBR treatment performance. 相似文献
95.
Computed tomography (CT) is increasingly employed in orthodontic treatment. One of the most successful applications is in dental implantology, in which an artificial root is surgically inserted into the jawbone to provide anchorage for a dental prosthesis. For successful implant surgery, it is crucial to locate internal structures such as the inferior alveolar nerve canal (IAC). This paper presents a computerized technique for extracting the IAC. To facilitate the extraction, we first generate panoramic CT images (panoramics) by reformatting the original CT images. The panoramics are a series of cross-sectional images along curved planes through the mandible (lower jawbone). Hollow canals are subsequently detected by analyzing the voxel intensities and 3-D gradient orientations in the panoramics. The axis of the IAC is then traced out by a novel 3-D line-tracking technique. The method is effective for extracting the IAC despite the open structure of the surrounding bone. 相似文献
96.
ME Soberano EB Ong AJ Johnson M Levy G Schoellmann 《Canadian Metallurgical Quarterly》1976,445(3):763-773
Affinity chromatography on agmatine-Sepharose was used for the separation of two active forms of urokinase (EC 3.4.99.26) from partially purified human urinary urokinase. The approximate molecular weight of the heavier form was 47 000 and of the lighter 33 400. Both forms were homogeneous by sodium dodecyl sulfate gel electrophoresis and by 3H-labeled diisopropylphosphorofluoridate and 14C-labeled p-nitrophenyl-p'-guanidinobenzoate incorporation studies. The 33 400 mol. wt. form had a single chain, and the 47 000 mol. wt. form had two chains (33 100 and 18 600 mol. wt.) linked by disulfide bonds. The specific activity of the heavier form was 104 000 CTA units/mg protein, compared with 226 000 units/mg for the lighter form but the activities per mmol of active site (molar activities) of the two forms were almost identical (9.6-10(9) and 10.2-10(9) CTA units/mmol). Isoelectric focusing on gels showed that the 47 000 material contained one major subform with a pI of 8.60 and a minor subform with a pI of 8.90, while the 33 400 material had three major subforms with pI values of 8.35, 8.60 and 8.70, respectively, and a minor subform with a pI of 8.05. 3H-labeled diisopropylphosphorofluoridate incorporation studies revealed an active-site serine residue in the heavy chain. 相似文献
97.
Lee OK 《Journal of applied measurement》2003,4(1):10-23
The longitudinal measurement of ability growth requires that the measures that are taken at the various time points be obtained using the same yardstick. Tests given for this purpose, therefore, need to be equated. The popular practice still in use for the purpose of equating tests, is the grade-equivalent. This paper compares the observation of children's growth in reading using grade-equivalents with that using Rasch Simultaneous Vertical Equating procedure. It is found that grade equivalents differ much more between two different test forms compared to ability measures obtained using Rasch Simultaneous Vertical Equating. It is also found that the spread of students' grade-equivalents, increased over the years as they grow while the standard deviations of their Rasch measures remain relatively constant over the same period of time. Student responses to the ITBS Form 7 and the CPS90 and CPS 91 were used. A total of 5,623 students were tracked over eight years. 相似文献
98.
A framework for distributed manufacturing is proposed to facilitate collaborative product development and production among geographically distributed functional agents using digitalized information. Considering the complexity of products created in a distributed manufacturing scenario, it often requires close collaborations among a number of facilities. In this research work, various functional agents, such as the manufacturability evaluation agent (MEA), manufacturing resource agent (MRA), process-planning agent (PPA), manufacturing scheduling agent (MSA), shop floor agent (SFA), fault diagnosis agent (FDA), etc., can interact coherently for distributed manufacturing. With specific agents having unique functionalities, a manufacturing managing agent (MMA) acts as the centre of this distributed manufacturing system. The MMA agent assists the specific agents’ to work seamlessly and also to collaborate closely with the participating agents. In this way, the production cycle of a part can be optimized from product design to final manufacturing since all the production procedures are considered logically and every procedure is correlated. The agent language based on the knowledge query manipulation language (KQML) includes many pre-defined performatives that ease the participating agents to carry out their tasks intelligently by interpreting commands from one another. Additionally, to ensure the adaptiveness and upgradeability of the system, the internal structure of each functional agent that is based on JATLite is modularized into several components, including a communication interface, central work engine, knowledge base pool, and input/output modifier for possible future methodology enhancements. 相似文献
99.
Zexuan Zhu Yew-Soon Ong Manoranjan Dash 《IEEE transactions on systems, man, and cybernetics. Part B, Cybernetics》2007,37(1):70-76
This correspondence presents a novel hybrid wrapper and filter feature selection algorithm for a classification problem using a memetic framework. It incorporates a filter ranking method in the traditional genetic algorithm to improve classification performance and accelerate the search in identifying the core feature subsets. Particularly, the method adds or deletes a feature from a candidate feature subset based on the univariate feature ranking information. This empirical study on commonly used data sets from the University of California, Irvine repository and microarray data sets shows that the proposed method outperforms existing methods in terms of classification accuracy, number of selected features, and computational efficiency. Furthermore, we investigate several major issues of memetic algorithm (MA) to identify a good balance between local search and genetic search so as to maximize search quality and efficiency in the hybrid filter and wrapper MA 相似文献
100.
J. P. Yang J. Q. Mou N. B. Chong Y. Lu H. Zhu Q. Jiang W. G. Kim J. Chen G. X. Guo E. H. Ong 《Microsystem Technologies》2007,13(8-10):733-740
In this paper, we present novel micro-electro-mechanical systems (MEMS) devices for unique probe recording technology, where the 1-D cantilever probe array approach requires a small number of cantilever probe tips for a large media platform and hence has higher reliability. The probe storage system is composed of three key MEMS devices: MEMS XY-stage, linear motor and 1-D cantilever probe array with integrated heater. The design and fabrication process of three MEMS devices are given with prototypes. Their performances are discussed with the experimental results. The compact MEMS XY-stage device can be driven with ±20 μm movement, in X- and Y-directions. The miniature linear motor is smoothly driven to move back and forth at the speed of 20 mm/s and step of 150 μm by 150 mA pulse driving current. The indented (writing) bit size of 100 nm on polymer media is achieved by the prototyped cantilever probe tip with integrated heater. 相似文献