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1.
For the development of new crystal and electronic structures in molecular conductors, dimeric tetrathiafulvalene (TTF) and tetraselenafulvalenes (TSFs)1–3 linked by single or double methyl antimony bridge(s) have been prepared and their neutral crystal structures have been investigated. The donor2 (cis-2) forms a metallic cation radical salt with tetracyanoquinodimethane (TCNQ) containing one-dimensional array interactions.  相似文献   
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In this paper, we propose a new online identification approach for evolving Takagi–Sugeno (TS) fuzzy models. Here, for a TS model, a certain number of models as neighboring models are defined and then the TS model switches to one of them at each stage of evolving. We define neighboring models for an in-progress (current) TS model as its fairly evolved versions, which are different with it just in two fuzzy rules. To generate neighboring models for the current model, we apply specially designed split and merge operations. By each split operation, a fuzzy rule is replaced with two rules; while by each merge operation, two fuzzy rules combine to one rule. Among neighboring models, the one with the minimum sum of squared errors – on certain time intervals – replaces the current model.To reduce the computational load of the proposed evolving TS model, straightforward relations between outputs of neighboring models and that of current model are established. Also, to reduce the number of rules, we define and use first-order TS fuzzy models whose generated local linear models can be localized in flexible fuzzy subspaces. To demonstrate the improved performance of the proposed identification approach, the efficiency of the evolving TS model is studied in prediction of monthly sunspot number and forecast of daily electrical power consumption. The prediction and modeling results are compared with that of some important existing evolving fuzzy systems.  相似文献   
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This paper introduces a methodology to analyze geometrically the singularities of manipulators, of which legs apply both actuation forces and constraint moments to their moving platform. Lower mobility parallel manipulators and parallel manipulators, of which some legs have no spherical joint, are such manipulators. The geometric conditions associated with the dependency of six PlUumlcker vectors of finite lines or lines at infinity constituting the rows of the inverse Jacobian matrix are formulated using Grassmann-Cayley algebra (GCA). Accordingly, the singularity conditions are obtained in vector form. This study is illustrated with the singularity analysis of four manipulators.  相似文献   
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Analytical decision making strategies rely on weighing pros and cons of multiple options in an unbounded rationality manner. Contrary to these strategies, recognition primed decision (RPD) model which is a primary naturalistic decision making (NDM) approach assumes that experienced and professional decision makers when encounter problems in real operating conditions are able to use their previous experiences and trainings in order to diagnose the problem, recall the appropriate solution, evaluate it mentally, and implement it to handle the problem in a satisficing manner. In this paper, a computational form of RPD, now called C-RPD, is presented. Unified Modeling Language was used as a modeling language to represent the proposed C-RPD model in order to make the implementation easy and obvious. To execute the model, RoboCup Rescue agent simulation environment, which is one of the best and the most famous complex and multi-agent large-scale environments, was selected. The environment simulates the incidence of fire and earthquakes in urban areas where it is the duty of the police forces, firefighters and ambulance teams to control the crisis. Firefighters of SOS team are first modeled and implemented by utilizing C-RPD and then the system is trained using an expert’s experience. There are two evaluations. To find out the convergence of different versions developed during experience adding, some of the developed versions are chosen and evaluated on seven maps. Results show performance improvements. The SOS team ranked first in an official world championship and three official open tournaments.  相似文献   
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Dialysis adequacy indexed by Kt/V in hemodialysis (HD) patients is recommended as a single-pool Kt/V of at least 1.2 per session thrice weekly. But many patients cannot achieve this adequacy target. Although dialysis time is the most important as a factor influencing Kt/V, it is difficult to prolong dialysis time in practice because of its economic impact and poor patient compliance.
Objective:  The aim of this study is to investigate the effect of increasing blood flow rate on dialysis adequacy in HD patients with low Kt/V.
Methods:  This study enrolled 36 HD patients with single-pool Kt/V <1.2 per session thrice weekly, which was measured in dialyzer blood flow rate of 230 mL/min. We increased 15% of blood flow rate in patients <65 kg of body weight and 20% in patients >65 kg. And then we compared Kt/V and urea reduction ratio (URR) between before and after increasing blood flow rate.
Results:  The mean age was 48 ± 11 years (23–73 years), and the number of males was 25. Of the total patients, 24 patients had dry weight <65 kg. Mean dialysis duration was 52 ± 50 months (3–216 months). Mean Kt/V before increasing blood flow rate was 1.02 ± 0.09. It increased to 1.14 ± 0.12 after increasing blood flow rate (p < 0.001). Of the total 36 patients, 13 patients (36.1%) achieved adequacy target (Kt/V ≤ 1.2). Mean URR before increasing blood flow rate was 56.9 ± 4.0%. It also increased to 60.8 ± 4.1% (p < 0.001).
Conclusion:  Our data suggest that increasing blood flow rate by 15–20% of previous flow rate is effective in achieving dialysis adequacy in HD patients with low Kt/V.  相似文献   
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