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91.
In this paper, for one-dimensional stochastic linear fractional systems in terms of the Riemann–Liouville fractional derivative, the optimal control is derived. It is assumed that the state is completely observable and all the information regarding this is available. The formulation leads to a set of stochastic fractional forward and backward equation in the Riemann–Liouville sense. The proposed method has been checked via some numerical simulations which show the effectiveness of the fractional stochastic optimal algorithm. 相似文献
92.
Luc Laperrière Dr Hoda A. ElMaraghy 《The International Journal of Advanced Manufacturing Technology》1994,9(4):231-244
This paper describes a Generative Assembly Process Planner (GAPP) used to generate and evaluate assembly sequence alternatives which can be used in simultaneous engineering applications. Given a graph model of the product to be assembled, optimal assembly sequences are automatically generated and evaluated in a single process. Geometric feasibility and accessibility constraints on assembly operations which help prune the search space are presented. Assembly-related criteria which guide the search to an optimal solution are described. These include: number of reorientations, concurrent execution of assembly tasks, grouping of similar tasks and stability criteria. The relative weights of various criteria can be varied interactively resulting in different optimal assembly sequences. The ability of GAPP to generate and evaluate assembly alternatives when various criteria are enabled or disabled or their relative importance is changed makes it an effective tool for simultaneous engineering/manufacturing applications. Examples are included to demonstrate GAPP's use and potential for assessing assembly, disassembly, repair and maintenance procedures. 相似文献
93.
Yejin Lee Hoda Shafaghat Jae-kon Kim Jong-Ki Jeon Sang-Chul Jung In-Gu Lee Young-Kwon Park 《Korean Journal of Chemical Engineering》2017,34(8):2180-2187
Tungstated zirconia (WO3/ZrO2 with WO3 loadings of 9.9 (WZ9.9), 15.5 (WZ15.5), and 15.7 wt% (WZ15.7)) and Amberlyst (15, 35, 36, 39 and 45) catalysts were employed to upgrade pyrolysis bio-oil of acacia sawdust through an esterification reaction using methanol at atmospheric pressure and room temperature or 80 °C. The upgrading efficiency was evaluated by measuring the total acid number (TAN) and viscosity. The viscosity and TAN of the resulting upgraded bio-oil were found to be dependent on the calcination temperature of the WO3/ZrO2 catalysts. At room temperature, the largest decrease in viscosity and TAN of the bio-oil and methanol mixture was obtained using WZ9.9 tungstated zirconia calcined at 900 °C. An increase in reaction temperature to 80 °C improved the flowability and TAN of the methanol-added bio-oil using WZ9.9 activated at 900 °C. The product distribution of the bio-oil upgraded using methanol revealed esterification to be the dominant reaction pathway under the reaction conditions of this study. When the ether extracted bio-oil was upgraded at 80 °C using methanol over catalysts, the Amberlyst catalysts were found more effective than tungstated zirconia catalysts in enhancing the esterification reaction and reducing TAN. 相似文献
94.
95.
Dr. Clare F. Megarity Dr. Hoda Abdel-Aal Bettley Dr. M. Clare Caraher Dr. Katherine A. Scott Dr. Roger C. Whitehead Dr. Thomas A. Jowitt Dr. Aldo Gutierrez Dr. Richard A. Bryce Dr. Karen A. Nolan Prof. Ian J. Stratford Prof. David J. Timson 《Chembiochem : a European journal of chemical biology》2019,20(22):2841-2849
NAD(P)H quinone oxidoreductase-1 (NQO1) is a homodimeric protein that acts as a detoxifying enzyme or as a chaperone protein. Dicourmarol interacts with NQO1 at the NAD(P)H binding site and can both inhibit enzyme activity and modulate the interaction of NQO1 with other proteins. We show that the binding of dicoumarol and related compounds to NQO1 generates negative cooperativity between the monomers. This does not occur in the presence of the reducing cofactor, NAD(P)H, alone. Alteration of Gly150 (but not Gly149 or Gly174) abolished the dicoumarol-induced negative cooperativity. Analysis of the dynamics of NQO1 with the Gaussian network model indicates a high degree of collective motion by monomers and domains within NQO1. Ligand binding is predicted to alter NQO1 dynamics both proximal to the ligand binding site and remotely, close to the second binding site. Thus, drug-induced modulation of protein motion might contribute to the biological effects of putative inhibitors of NQO1. 相似文献
96.
Hannah Kim Hoda Shafaghat Jae-kon Kim Bo Sung Kang Jong-Ki Jeon Sang-Chul Jung In-Gu Lee Young-Kwon Park 《Korean Journal of Chemical Engineering》2018,35(4):922-925
A low cost alkaline catalyst of dolomite (CaMg(CO3)2) was used to stabilize acacia sawdust bio-oil mixed with methanol. The upgrading efficiency was evaluated in terms of the total acid number (TAN) and viscosity. A change in the dolomite calcination temperature from 700 to 900 °C led to a significant change in the TAN and viscosity of the methanol-added bio-oil. Dolomite activated at higher temperatures had larger amounts of active CaO and MgO species due to the enhanced decarboxylation of calcium and magnesium carbonates. An increase in the dolomite content (1-5 wt%) decreased the TAN value of bio-oil remarkably. A thermal aging test of the methanol-added bio-oil upgraded using dolomite (calcined at 900 °C) at 50 °C for 24 h was carried out by storing the bio-oil at 80 °C for one week. Although the TAN value increased after the aging process, it was still lower than the TAN of raw bio-oil. In addition, increasing the methanol content (10-30 wt%) decreased the TAN and viscosity of the bio-oil significantly. 相似文献
97.
Navideh Anarjan Hoda Jafarizadeh Malmiri Tau Chuan Ling 《International Journal of Food Properties》2013,16(4):937-947
In this work, astaxanthin nanodispersions were prepared using selected three component stabilizer system through a solvent-diffusion technique, with the particle size of 98.3 nm. The stability of produced nanodispersions against pH, salts, and heating were then evaluated. The produced nanodispersions exhibited good physical stability under wide ranges of pH (except around isoelectric point), sodium ion concentrations, and relatively high-temperature treatments (up to 60°C). However, formation of large particles was observed in either presence of calcium ions or higher thermal treatments (more than 60°C). 相似文献
98.
99.
Sarah Lord Ferguson Leanne Ewing Alessandro Bigi Hoda Diba 《Journal of Wine Research》2019,30(2):157-165
This paper considers a sample of successful wine bloggers, and clusters them into four distinct segments that could be targeted by wine marketers in different ways. Using text that they wrote in response to being named to a survey of 100 top wine blogs, we employ an advanced textual analysis tool (LIWC) to categorize the writings according to the following characteristics: analytical thinking, clout, authenticity, and emotional tone. This data is then used in a clustering procedure that distinguishes four distinct groups of bloggers: the Analysts, the Agnostics, the Authentic Pessimists, and the Confident Optimists. 相似文献
100.
The aim of inspection planning tasks is to ensure the generation of efficient operation for coordinate measurement machines (CMMs). This paper presents a methodology to automatically define the accessibility domain of measurement points and then group them into a set of clusters. The methodology uses the computer-aided design (CAD) model of the workpiece and tolerance information as input to an algorithm for defining points accessibility. For each measurement point, the algorithm determines all feasible inspection probe orientations, as a subset of the total set of available orientations for a given CMM probe. A heuristic algorithm then groups the measurement points into a set of clusters which provide the maximum number of probe orientations. This methodology was applied to three examples which contain solid model and free-form surface representations. 相似文献