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51.
在对生产现场的设备进行诊断检测时,由于设备的个性和测试数据的零散性往往很不容易决定正常与异常的边界值,即判定基准.为了解决这问题,笔者应用概率统计方法、可能性理论以及现场的实际情况,对用于设备诊断的有量纲与无量纲的特征参数,提出几种决定设备诊断判定基准的方法.并且采用现场实际数据进行验证.  相似文献   
52.
The frequencies of isolation and susceptibilities to antimicrobial agents were investigated on 680 bacterial strains isolated from patients with urinary tract infections (UTIs) in 10 hospitals during the period of June 1996 to May 1997. Of the above bacterial isolates, Gram-positive bacteria accounted for 30.4% and a majority of them were Enterococcus faecalis. Gram-negative bacteria accounted for 69.6% and most of them were Escherichia coli. Susceptabilities of several isolated bacteria to antimicrobial agents were as followed; 1. Enterococcus faecalis Ampicillin (ABPC) showed the highest activity against E. faecalis isolated from patients with UTIs. Its MIC90 was 1 microgram/ml. Imipenem (IPM) and vancomycin (VCM) were also active with the MIC90S of 2 micrograms/ml. The others had low activities with the MIC90S of 16 micrograms/ml or above. 2. Staphylococcus aureus including MRSA Arbekacin (ABK) and VCM showed the highest activities against both S. aureus and MRSA isolated from patients with UTIs. The MIC90S of them were 1 or 2 micrograms/ml. The others except minocycline (MINO) had low activities with the MIC90S of 32 micrograms/ml or above. 3. Staphylococcus epidermidis ABK and VCM showed the strongest activities against S. epidermis isolated from patients with UTIs. The MICs for all strains were equal to or lower than 2 micrograms/ml. Cefazolin (CEZ), cefotiam (CTM) and cefozopran (CZOP) were also active with the MIC90S of 4 micrograms/ml. Compared with antimicrobial activities of cephems is 1995, the MIC90S of them had changed into a better state. They ranged from 4 micrograms/ml 16 micrograms/ml in 1996. 4. Streptococcus agalactiae All drugs except MINO were active against S. agalactiae. ABPC, CZOP, IPM, and clarithromycin (CAM) showed the highest activities. The MICs for all strains were equal to or lower than 0.125 micromilligrams. Tosufloxacin (TFLX) and VCM were also active with the MIC90S of 0.5 micromilligrams. 5. Citrobacter freundii Gentamicin (GM) showed the highest activity against C. freundii isolated from patients with UTIs. Its MIC90 was 0.5 micrograms/ml. IPM and amikacin (AMK) were also active with the MIC90S of 1 microgram/ml and 2 micrograms/ml, respectively. Cefpirome (CPR) and CZOP were also active with the MIC90S of 8 micrograms/ml. The MIC90S of the others were 16 micrograms/ml or above. 6. Enterobacter cloacae IPM showed the highest activity against E. cloacae. The MICs for all strains were equal to or lower than 0.5 microgram/ml. The MIC90S of ciprofloxacin (CPFX) and TFLX were 1 microgram/ml, the MIC90 of AMK was 2 micrograms/ml, the MIC90S of CZOP, GM and ofloxacin (OFLX) were 4 micrograms/ml. The MIC50S of cephems except CEZ, cefmetazole (CMZ) and cefaclor (CCL) had changed into a better state in 1996, compared with those in 1995. 7. Escherichia coli All drugs except penicillins and MINO were active against E. coli. Particularly CPR, CZOP and IPM showed the highest activities against E. coli. The MIC90S of them were 0.125 microgram/ml or below. Among E. coli strains, those with low susceptibilities to cephems except CEZ, cefoperazone (CPZ), latamoxef (LMOX) and CCL have increased in 1996, compared with those in 1995. 8. Klebsiella pneumoniae K. pneumoniae was susceptible to all drugs except penicillins, with the MIC90S of 2 micrograms/ml or below. CPR had the strongest activity, the MICs for all strains were equal to or lower than 0.25 microgram/ml. Flomoxef (FMOX), cefixime (CFIX), CZOP and carumonam (CRMN) were also active with the MIC90S of 0.125 microgram/ml or below. 9. Pseudomonas aeruginosa All drugs except quinolones were not so active against P. aeruginosa with the MIC90S were 32 micrograms/ml or above. Quinolones were more active in 1996 than 1995. The MIC90S of them were between 4 micrograms/ml and 8 micrograms/ml, and the MIC50S of them were between 1 microgram/ml and 2 micrograms/ml. 10. Serratia marcescens GM showed the highest activity against S. marcescens. Its MIC90 was 1 micro  相似文献   
53.
We theoretically study the thermoelectric properties of electron-doped FeAs2 and hole-doped PtSe2 from a band-structure point of view using first-principles band calculations. The band structure of both materials has a peculiar band shape with a flat portion at the top (bottom) of the band, namely the pudding-mold-type band as found in Na x CoO2. The pudding-mold-type band has a quasi-one-dimensional nature in FeAs2 and a quasi-two-dimensional nature in PtSe2. We study the origins of the pudding-mold-type band and find that the \( d_{z^2} \) orbital in FeAs2, and not only the p z but also the p x and the p y orbitals in PtSe2 play an important role in making the pudding-mold-type band. We calculate the Seebeck coefficients by the Boltzmann equation approach using a tight-binding model constructed from first-principles band calculations, finding values close to experimental observations. The present study shows the general efficiency of the pudding-mold-type band. We suggest that an efficient route towards obtaining good thermoelectric materials is to realize ideal pudding-mold-type bands by modification of lattice structures.  相似文献   
54.
Although many researches have been conducted on contouring control for machine tool feed drive systems, to the best of authors’ knowledge, its effectiveness has been verified only through comparative experiments with industrial non-contouring (independent axial) controllers, or conventional contouring controllers such as the cross-coupling controller. Because control performance largely depends on controller gains, such comparisons involve some difficulties in demonstrating the effectiveness of contouring control. In other words, a similar control performance can be achieved if the non-contouring controller gains are appropriately assigned. This paper discusses the effectiveness of contouring controllers both analytically and experimentally. A new contouring controller design for three-dimensional machining is presented, which is extended from the authors’ biaxial design based on coordinate transformation. The contouring controller is concluded to be effective through an analysis of the proposed design, in that it provides performance comparable to non-contouring controllers with less control input variance. This property reduces the damage to machine tool systems and saves control energy. In addition, because an inherent contour error exists in the coordinate transformation approach, a method for reducing this error is presented to enhance the effectiveness of the contouring controller. Experimental results support the claims of this paper.  相似文献   
55.
OBJECTIVES: (1) To assess the prevalence and the consequences of chronic verbal aggression, physical aggression, financial mistreatment, and neglect in a community-based sample; (2) to investigate the circumstances that led to the abuse and the ways in which the victims handled the problem. DESIGN: Prevalence was assessed in a population-based sample of 1797 older people living independently in Amsterdam, the Netherlands. In a follow-up study 1 year later, the victims were questioned again about the background and consequences of the abuse. RESULTS: The 1-year prevalence of elder abuse was 5.6%. The prevalence of the various types of elder abuse was: verbal aggression 3.2%, physical aggression 1.2%, financial mistreatment 1.4%, and neglect 0.2%. Most victims reported emotional reactions immediately after the abuse. Seven of 36 victims experienced physical or financial damage as a consequence of the abuse. More than 70% of the victims were able to stop the abuse, either by themselves or with the help of others. CONCLUSION: The rate of occurrence and the consequences of elder abuse in the Netherlands was established. Elder abuse is more widely spread if not only close relatives or people with whom the older person lives are considered as possible perpetrators but other familiar and trusted people are considered as well. Intervention should be focused on the roughly 40% of victims who were not able to stop the abuse.  相似文献   
56.
57.
Several data compression algorithms relating existing important source coding algorithms, including Ziv-Lempel codes, Rissanen's Context, and Welch's LZW method, are presented. First, an intermediate algorithm between the two Ziv-Lempel methods for universal data compression is proposed, which has the same asymptotic optimality as the well-known method based on the incremental parsing. The proposed algorithm is then compared with the context gathering algorithm. Context, in terms of gathering direction and gathering frequency. It is shown that while the proposed algorithm and Context have the same gathering frequency, they have opposite directions of context gathering. Practical variations are also considered. By combining the proposed algorithm with Welch's device, two practical data compression methods are obtained. They, as well as Welch's LZW method, start with a small table of symbol strings and build the table during compression and decompression. In practical methods, higher compression efficiency can be gained by accelerating the growth of the table  相似文献   
58.
Fly ashes are the waste product following the combustion of coal. Disposal of fly ashes is a serious environmental problem; therefore, finding a new utilization of fly ashes is highly demanded. Carbon nano-structures have been widely studied as key materials in a wide range of applications, including sensing, saturable absorber, and so on, because of its optical and electromagnetic absorption property. Adding the property of carbon nanotubes (CNTs) to fly ashes expands applications of fly ashes. In this paper, we present the fabrication of multi-walled carbon nanotubes (MWCNTs) on fly ashes by thermal chemical vapor deposition (CVD) process, which result in simple, low-cost, large-amount production of MWCNTs. Copyright © 2009 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.  相似文献   
59.
60.
Organization self-design of distributed production systems   总被引:3,自引:0,他引:3  
The authors introduce two reorganization primitives, composition and decomposition, which change the population of agents and the distribution of knowledge in an organization. To create these primitives, they formalize organizational knowledge, which represents knowledge of potential and necessary interactions among agents in an organization. The authors develop computational organizational self-design (OSD) techniques for agents with architectures based on production systems to take advantage of the well-understood body of theory and practice. They first extend parallel production systems, where global control exists, into distributed production systems, where problems are solved by a society of agents using distributed control. Then they introduce OSD into distributed production systems to provide adaptive work allocation. Simulation results demonstrate the effectiveness of the approach in adapting to changing environmental demands. The approach affects production system design and improves the ability of build production systems that can adapt to changing real-time constraints  相似文献   
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