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91.
Competitiveness involves the struggle and striving among businesses that are supposedly more or less evenly matched for the same objects (customers and markets) that have a limited supply. This paper identifies the problems within and among industries that may cause a decline in the level of productivity effectiveness and quality, and puts forward proposals and suggestions for companies that want to retain or regain their competitive edge. 相似文献
92.
Surendra K. Martha Hadar Sclar Zvi Szmuk Framowitz Daniela Kovacheva Nikolay Saliyski Yosef Gofer Pessia Sharon Eran Golik Boris Markovsky Doron Aurbach 《Journal of power sources》2009
In this paper we compare the behavior of LiNi0.5Mn0.5O2, LiNi0.33Mn0.33Co0.33O2 (NMC) and LiNi0.4Mn0.4Co0.2O2 as cathode materials for advanced rechargeable Li-ion batteries. These materials were prepared by a self-combustion reaction (SCR) from the metal nitrates and sucrose, followed by calcination at elevated temperatures. The temperature and duration of calcination enabled the adjustment of the average particle size and size distribution. It was established that the annealing temperature (700–900 °C) of the as-prepared oxides influences strongly the crystallite and particle size, the morphology of the material, and the electrochemical performance of electrodes in Li-cells. Capacities up to 190, 180 and 170 mAh g−1 could be obtained with Li[NiMn]O2, LiNi0.4Mn0.4Co0.2O2 and LiNi0.33Mn0.33Co0.33O2, respectively. In terms of rate capability, the order of these electrodes is NMC < LiNi0.4Mn0.4Co0.2O2 ? Li[NiMn]O2. Many hundreds of cycles at full DOD could be obtained with Li[NiMn]O2 and NMC electrodes in Li-cells, at room temperature. All of these materials develop a unique surface chemistry that leads to their passivation and stabilization in standard electrolyte solutions (alkyl carbonates/LiPF6). The surface chemistry was studied by FTIR, XPS and Raman spectroscopy and is discussed herein. 相似文献
93.
Daniela Kovacheva Boris Markovsky Gregory Salitra Yosef Talyosef Mila Gorova Elena Levi Michal Riboch Hyeong-Jin Kim Doron Aurbach 《Electrochimica acta》2005,50(28):5553-5560
A comparative analysis of the electrochemical behavior and Li+ transport characteristics of thin-layer LiNi0.5Mn1.5O4 intercalation electrodes comprised of micro- or nano-sized particles in standard Li salt solutions, was carried out and is reported herein. These electrodes were free of any conductive additives and polymeric binder in order to avoid their complex impact on the electrochemical response of the active mass. It was clearly established that the electrodes prepared from nanoparticles of the active mass show faster kinetics and a more reversible electrochemical behavior compared to the electrodes comprising microparticles.
The response of the nanoparticles to electrochemical techniques such as linear sweep voltammetry and potentiostatic intermittent titration (PITT) is characterized by high resolution. Thus D versus E could be calculated very precisely. It was encouraging to realize the good performance of the electrodes comprising nano-LiMn1.5Ni0.5O4, in spite of their high surface area and their high operating voltage. 相似文献
94.
We carry out a comprehensive analysis of a range of wireless network efficiency considerations. Firstly, we explore the properties and the implications of the power-versus bandwidth-efficiency criteria. Secondly, we perform a detailed top-down analysis of a typical commercial wireless network, which emphasizes the inherent differences between the aforementioned two efficiency metrics, while demonstrating that the appropriate choice of the network optimization criterion can have a profound effect on the over... 相似文献
95.
Avshalom Elmalech David Sarne Noa Agmon 《Autonomous Agents and Multi-Agent Systems》2016,30(3):506-525
This paper studies to what extent agent development changes one’s own strategy. While this question has many general implications it is of special interest to the study of peer designed agents (PDAs), which are computer agents developed by non-experts. This latter emerging technology, has been widely advocated in recent literature for the purpose of replacing people in simulations and investigating human behavior. Its main premise is that strategies programmed into these agents reliably reflect, to some extent, the behavior used by their programmers in real life. We show that PDA development has an important side effect that has not been addressed to date—the process that merely attempts to capture one’s strategy is also likely to affect the developer’s strategy. This result has many implications concerning the appropriate design of PDA-based simulations as well as the validity of using PDAs for studying individual decision making. The phenomenon is demonstrated experimentally, using two very different application domains and several performance measures. Our findings suggest that the effects on one’s strategy arise both in situations where it is potentially possible for people to reason about the optimal strategy (in which case PDA development will enhance the use of an optimal strategy) and in those where calculating the optimal strategy is computationally challenging (in which case PDA development will push people to use more effective strategies, on average). Since in our experiments PDA development actually improved the developer’s strategy, PDA development can be suggested as a means for improving people’s problem solving skills. Finally, we show that the improvement achieved in people’s strategies through agent development is not attributed to the expressive aspect of agent development per-se but rather there is a crucial additional gain in the process of designing and programming ones strategy into an agent. 相似文献
96.
R Hauser A Botchan A Amit D Ben Yosef R Gamzu G Paz JB Lessing L Yogev H Yavetz 《Canadian Metallurgical Quarterly》1998,13(11):3081-3085
Spermatogenesis may be focal in non-obstructive azoospermia. The present study was conducted to determine whether the performance of multiple, rather than a single testicular sample contributes to obtaining spermatozoa in amounts sufficient for fertilization and cryopreservation in non-obstructive, azoospermic patients. Furthermore, the aim was to clarify the significance of location for retrieval from the testis in such cases. Three biopsies were taken from identical locations in 55 testes of 29 men with non-obstructive azoospermia: (i) the rete testis region, ii) the midline, and (iii) the proximal region of the testis. When sperm cells were detected, they were used for intracytoplasmic sperm injection (ICSI), and the remainder were then cryopreserved in as many aliquots as possible (adjusted for ICSI procedure). Spermatozoa were found in 28 testes (50.9%) of 18 men (62.1%). In the testes from which spermatozoa were obtained, they were present in three, two or one locations in 15 (53.6%), five (17.9%) and eight (28.6%) cases respectively. The possibility of finding spermatozoa was not influenced by the location in the testis. Multiple testicular sperm extraction is recommended in cases of non-obstructive azoospermia, since it may enhance diagnostic accuracy of absolute testicular failure and increase the number of sperm cells retrieved. 相似文献
97.
Joshua Miron Ran Solomon Gabriel Adin Uri Nir Moses Nikbachat Edith Yosef Avner Carmi Zwi G. Weinberg Tal Kipnis Ephraim Zuckerman Daniel Ben‐Ghedalia 《Journal of the science of food and agriculture》2006,86(1):140-147
The effect of growth stage and re‐growth on the nutritional and ensilage characteristics of two new sorghum hybrids, BMR‐101 and Silobuster, and one commercial variety, FS‐5, was examined in this study. Varieties were sampled during the summer at the early heading (EH) stage and were harvested at the soft dough (SD) stage. Additional irrigation enabled autumn re‐growth and a second harvest. Plants of FS‐5 and BMR‐101 were resistant to lodging at EH. However, BMR‐101 and Silobuster suffered from high lodging at the SD stage of the summer harvest. Dry matter (DM) content of FS‐5 and BMR‐101 at EH was below 250 g kg?1. DM yields of the varieties were similar at the summer harvest and higher than their respective re‐growth cuts. Ensilage DM losses were moderate and similar across varieties. Hemicellulose of SD plants was partly solubilised and most of the water‐soluble carbohydrate fermented, yielding lactic acid, ethanol and volatile fatty acids (VFA), and a pH < 4. In vitro DM digestibility of varieties was similar in summer silages, but lower in the respective re‐growth silages of FS‐5 and BMR‐101, reflecting the higher content of neutral detergent fibre and lignin in the re‐growth silages. The summer plus re‐growth cumulative yields of digestible DM of the respective FS‐5, Silobuster and BMR‐101 silages were 14.7, 16.6 and 14.5 t ha?1. The commercial variety, FS‐5, may have some advantage over BMR‐101 and Silobuster owing to its relative resistance to lodging in addition to its high yield and good ensilage properties. Copyright © 2005 Society of Chemical Industry 相似文献
98.
99.
I Ikeda H Yoshida M Tomooka A Yosef K Imaizumi H Tsuji A Seto 《Canadian Metallurgical Quarterly》1998,33(9):897-904
To clarify the clinical features of nosocomial pneumonia during mechanical ventilation (ventilator-associated pneumonia) and to select the appropriate antibiotic therapy for patients, we performed a clinical analysis of 19 patients (26 episodes) with this condition. The following results were obtained. 1, The average age of the patients was 68 years old (male 16, female 3). 2, VAP occurred three times in 2 cases, twice in 3 cases, and once in 14 cases. 3, The duration of mechanical ventilation was from 7 days to 11 years and 5 months (the average was 2.1 years). 4, The microorganism isolated from the aspiration sputum of the VAP patients was Pseudomonas aeruginosa frequently, but it was difficult to determine whether this microorganism was the causative microorganism. Ten strains of Staphylococcus aureus (MRSA seven strains and MSSA three strains) were newly isolated at the same time as VAP and especially in the cases in which these were thought to be causative microrganisms, all the patients died within a short time. 5, Antibiotics were clinically effective for 53.8% of all the VAP patients and carbapenem antibiotics (for example, IPM/CS) were also used for the effective group. 6, Regarding the risk factors for VAP, factors such as the duration of mechanical ventilation, the existence of chronic obstructive pulmonary disease, a hyponutritional state, prior antibiotics, aspiration of gastric contents, histamine-type-2 receptor antagonist, and multiple organ failure showed significant differences and were suspected to be associated with the appearance of VAP. 相似文献
100.
We put forward extensions to the Sherif-Dear Simple (SDS) Theorem, prove these extensions by enumeration, and cite some relevant applications. “The essence of research is its freedom.” 相似文献