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排序方式: 共有2777条查询结果,搜索用时 15 毫秒
61.
Sanabria NR Peralta YM Monta?ez MK Rodríguez-Valencia N Molina R Moreno S 《Water science and technology》2012,66(8):1663-1668
The effluent from the anaerobic biological treatment of coffee wet processing wastewater (CWPW) contains a non-biodegradable compound that must be treated before it is discharged into a water source. In this paper, the wet hydrogen peroxide catalytic oxidation (WHPCO) process using Al-Ce-Fe-PILC catalysts was researched as a post-treatment system for CWPW and tested in a semi-batch reactor at atmospheric pressure and 25 °C. The Al-Ce-Fe-PILC achieved a high conversion rate of total phenolic compounds (70%) and mineralization to CO(2) (50%) after 5 h reaction time. The chemical oxygen demand (COD) of coffee processing wastewater after wet hydrogen peroxide catalytic oxidation was reduced in 66%. The combination of the two treatment methods, biological (developed by Cenicafé) and catalytic oxidation with Al-Ce-Fe-PILC, achieved a 97% reduction of COD in CWPW. Therefore, the WHPCO using Al-Ce-Fe-PILC catalysts is a viable alternative for the post-treatment of coffee processing wastewater. 相似文献
62.
Markets liquidity is an issue of very high concern in financial risk management. In a perfect liquid market the option pricing model becomes the well-known linear Black–Scholes problem. Nonlinear models appear when transaction costs or illiquid market effects are taken into account. This paper deals with the numerical analysis of nonlinear Black–Scholes equations modeling illiquid markets when price impact in the underlying asset market affects the replication of a European contingent claim. Numerical analysis of a nonlinear model is necessary because disregarded computations may waste a good mathematical model. In this paper we propose a finite-difference numerical scheme that guarantees positivity of the solution as well as stability and consistency. 相似文献
63.
Juan L. Mata-Machuca Rafael Martínez-Guerra 《Computers & Mathematics with Applications》2012,63(6):1072-1078
In this paper we deal with the observer-based asymptotic synchronization problem for a class of chaotic oscillators. Some results based on a differential algebraic approach are used in order to determine the algebraic observability of unknown variables. The strategy consists of proposing a slave system (observer) which tends to follow asymptotically the master system. The methodology is tested in the real-time asymptotic synchronization of the Colpitts oscillator by means of a proportional reduced order observer (PROO) of free-model type. 相似文献
64.
A multi-objective evolutionary algorithm for an effective tuning of?fuzzy logic controllers in?heating, ventilating and air conditioning systems 总被引:5,自引:5,他引:0
This paper focuses on the use of multi-objective evolutionary algorithms to develop smartly tuned fuzzy logic controllers
dedicated to the control of heating, ventilating and air conditioning systems, energy performance, stability and indoor comfort
requirements. This problem presents some specific restrictions that make it very particular and complex because of the large
time requirements needed to consider multiple criteria (which enlarge the solution search space) and the long computation
time models required in each evaluation. 相似文献
65.
This paper describes a heterogeneous modular robot system design which attempts to give a quick solution to a diversity of tasks. The approach is based on the use of an inventory of three types of modules i.e., power and control module, joint module and specialized module. Each module type aims to balance versatility and functionality. Their design permits rapid and cost effective design and fabrication. They are interchangeable in different ways to form different robot or system configurations. Depending on the task, the operator decides what type of robot can provide the best performance within the mission. A spherical joint module is described and used to build different robots, hence, forward and inverse kinematics models are obtained. Finally, from the modules described in this work, several robot configurations such as robotic arms, leg-based robots and wheel-based robots are assembled to demonstrate the execution of manipulation and locomotion tasks. 相似文献
66.
67.
Louise A. Dennis Michael Fisher Matthew P. Webster Rafael H. Bordini 《Automated Software Engineering》2012,19(1):5-63
In this paper we describe a verification system for multi-agent programs. This is the first comprehensive approach to the verification of programs developed using programming languages based on the BDI (belief-desire-intention)
model of agency. In particular, we have developed a specific layer of abstraction, sitting between the underlying verification
system and the agent programming language, that maps the semantics of agent programs into the relevant model-checking framework.
Crucially, this abstraction layer is both flexible and extensible; not only can a variety of different agent programming languages
be implemented and verified, but even heterogeneous multi-agent programs can be captured semantically. In addition to describing this layer, and the semantic mapping inherent
within it, we describe how the underlying model-checker is driven and how agent properties are checked. We also present several
examples showing how the system can be used. As this is the first system of its kind, it is relatively slow, so we also indicate
further work that needs to be tackled to improve performance. 相似文献
68.
69.
Antonio Lpez Rafael Molina Aggelos K. Katsaggelos Antonio Rodriguez Jos M. Lpez Jos M. Llamas 《International journal of imaging systems and technology》2004,14(1):21-27
Despite the adequacy of Bayesian methods to reconstruct nuclear medicine SPECT (single‐photon emission computed tomography) images, they are rarely used in everyday medical practice. This is primarily because of their computational cost and the need to appropriately select the prior model hyperparameters. We propose a simple procedure for the estimation of these hyperparameters and the reconstruction of the original image and test the procedure on both synthetic and real SPECT images. The experimental results demonstrate that the proposed hyperparameter estimation method produces satisfactory reconstructions. Although we have used generalized Gaussian Markov random fields (GGMRF) as prior models, the proposed estimation method can be applied to any priors with convex potential and tractable partition function with respect to the scale hyperparameter. © 2004 Wiley Periodicals, Inc. Int J Imaging Syst Technol 14, 21–27, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ima.20003 相似文献
70.
Giulia Minniti Letícia Maria Pescinini-Salzedas Guilherme Almeida dos Santos Minniti Lucas Fornari Laurindo Sandra Maria Barbalho Renata Vargas Sinatora Lance Alan Sloan Rafael Santos de Argollo Haber Adriano Cressoni Araújo Karina Quesada Jesselina F. dos Santos Haber Marcelo Dib Bechara Katia Portero Sloan 《International journal of molecular sciences》2022,23(21)
Sarcopenia is a disease that becomes more prevalent as the population ages, since it is directly linked to the process of senility, which courses with muscle atrophy and loss of muscle strength. Over time, sarcopenia is linked to obesity, being known as sarcopenic obesity, and leads to other metabolic changes. At the molecular level, organokines act on different tissues and can improve or harm sarcopenia. It all depends on their production process, which is associated with factors such as physical exercise, the aging process, and metabolic diseases. Because of the seriousness of these repercussions, the aim of this literature review is to conduct a review on the relationship between organokines, sarcopenia, diabetes, and other metabolic repercussions, as well the role of physical exercise. To build this review, PubMed-Medline, Embase, and COCHRANE databases were searched, and only studies written in English were included. It was observed that myokines, adipokines, hepatokines, and osteokines had direct impacts on the pathophysiology of sarcopenia and its metabolic repercussions. Therefore, knowing how organokines act is very important to know their impacts on age, disease prevention, and how they can be related to the prevention of muscle loss. 相似文献