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Abstract: Through the research on the existing fuzzy control algorithms, this paper improves the adaptive fuzzy control algorithm. In the identification of the impulse response model of the controlled object, the improved algorithm not only identifies each component size of the impulse response sequence, but also identifies the sequence itself, thus improving the speediness of the control system. [Copyright &y& Elsevier]

Abstract: In order to realize precise laser welding of the aerospace thin sheet parts, it is necessary to model the 3-D butt joint accurately. Due to narrow seam gap and little misalignment of the butt joint, it is difficult to extract all the feature information such as 3-D seam position, surface normal and gap width in a lump by traditional methods or sensors. Furthermore, these feature information acquired by laser vision sensor are just expressed in local measuring coordinate system, which can’t be used for global modeling directly. In this paper, a mathematical modeling method based on the kinematic model of the laser welding & measuring machine tool was proposed. The machine tool''s form-shaping function matrix was derived according to the homogeneous coordinate transformation matrix and the kinematic parameters. By using this form-shaping function matrix, the measured data could be converted into global data stably and accurately. Through B-spline surface fitting, the 3-D butt joint''s mathematical model including all the feature information was established. Experimental results demonstrate the effectiveness of the proposed method. [Copyright &y& Elsevier]

Abstract: This paper puts forward a mathematical method for computing the parallel extent of two image elements—a specific instance of the Gestalt law of parallelism. The experimental results show that the method is consistent with the human perception results. [Copyright &y& Elsevier]

Abstract: Fan is widely used in the industrial process, but fan usually have complicated nonlinear characteristics .The stronger degree of nonlinearity is, the bigger deviation between the model and actual process is. The performance of conventional linear controller will be significantly stepped down with enhanced nonlinearity of the controlled process. Many practical applications need the model of fan to be linearized. And the result is scribed in the paper which adopts the theory of linearization clan to deal with the relationships of the flow and pressure on nonlinear fan model. First, fan is given as a nonlinear object, and then is processed by using the linearization clan method, to get a series of linear models segments. These linear models are superimposed to describe the nonlinear model. Simulation results show the method of linearization clan can approximately describe the nonlinear system of fan, and it has good operability and value of application. [Copyright &y& Elsevier]

Abstract: The conceptual model''s reuse is a problem in simulation system''s development. In this paper, a conceptual model development method which supports reuse is given. The method centers about task, and generalizes the conceptual model development process to the following three steps: describing system structure and its implementation procedure, decomposing task and modeling behavior. After analyzing the method''s reusability, its good impact for raising the model''s reusability can be proved. Thereby, the method can be applied in the conceptual model''s development of simulation system [Copyright &y& Elsevier]

Abstract: Business process model plays an important role in model-driven development. When dealing with complex business process models, sometimes it is not easy to determine whether a process model contains any errors. The concepts such as cancellation and OR-joins occur naturally in business scenarios but the presence of these features in process models poses new challenges for verification. We take on the challenge of finding new verification techniques for business process models with cancellation regions and OR-joins. The proposed approach relies on anti-patterns matching. This paper verificate business process models by detecting errors illustrated by anti-patterns in the model. First we define some anti-patterns which frequently occur in business process models. We present these techniques in the context of business process modeling language YAWL that provides direct support for all the 20 control-flow patterns reported in . We have implemented a diagnostic tool based on anti-pattern detecting. [Copyright &y& Elsevier]

Abstract: Model transformations are frequently applied in model-driven development to bridge between languages on a different level of abstraction and formality. In This paper, we define a transformation from UML 2.0 Activity diagram(UML-AD for short) to YAWL, a formal workflow language that is able to capture all of the 20 workflow patterns reported in. The transformation is mainly concerned on the control-flow aspects of UML-AD models. We illustrate the transformation challenges and present a suitable transformation algorithm. The benefit of the transformation is threefold. First, it clarifies the semantics of UML-AD via a mapping to YAWL. Second, the deployment of UML-AD business process models as workflows is simplified. Third, UML-AD models can be analyzed with YAWL verification tools. a [Copyright &y& Elsevier]

Abstract: It is very important to get real factor and ideal factor for the spiral bevel gear''s error measurement and evaluation. According to its complexity tooth surface shape, the real factor was gotten by CMM which could measure the coordinates of the intersection points in the real gear tooth surface. For the ideal factor, this paper proposed that it was gotten by building the 3d solid modeling in UG based on the gear''s basic parameters and cutter head parameters. The application of 3d solid modeling in spiral bevel gear''s error measurement and evaluation was explained by measuring and evaluating the automobile rear axle''s driven gear. The result shows that this way is very effective and feasible. [Copyright &y& Elsevier]

Abstract: In this paper, four-wheel steering and direct yaw-moment integrated fuzzy controller is designed. To verify the effectiveness of the integrated fuzzy controller, a nonlinear three-degree-of-freedom model is employed for computer simulation. Considering the nonlinear effects of tyre, Pacejka tyre model was adopted to set up the nonlinear vehicle dynamic model. Simulation on the nonlinear vehicle with integrated controller in Matlab/Simulink software environment was described for a step input. The simulations suggest, compared with FWS and 4WS, the integrated controller can make the handling and stability performance on big lateral acceleration and slip angle improved, and make the driver drive the vehicle normally. The conclusion can be useful for the system design of vehicle stability control system. [Copyright &y& Elsevier]

Abstract: In this paper, we propose a Micro-modeling approach for pedestrian dynamics, which based on the agent technology. For this model, a computer program is developed to simulate and analyze evacuation phenomenon in sports stadium. Firstly, researches have analyzed the modeling method of agent and environment; the evacuation used the method of gird generation in venues and building individual decision-making model by agent. Secondly, we mainly study the behavior of sub-group, in order to reproduce the behavior, three cases have been studied to analyze the impact of evacuation. Simulation processes and results display that the model is very close to real movements of people. Therefore, this model can be used for the design of sports stadium and as the basis of command plans. [Copyright &y& Elsevier]

Abstract: Conventional multimodal biometrics systems usually do not account for missing data (missing modalities or incomplete score lists) that is commonly encountered in real applications. The presence of missing data in multimodal biometric systems can be inconvenient to the client, as the system will reject the submitted biometric data and request for another trial. In such cases, robust multimodal biometric verification is needed. In this paper, we present the criteria, fusion method and performance metrics of a robust multimodal biometrics verification system that verifies the client''s identity at any condition of data missing. A novel adaptive SVM classification method is proposed for missing dimensional values, which can handle the missing data in multimodal biometrics. We show that robust multibiometrics imposes additional requirements on multimodal fusion when compared to conventional multibiometrics. We also argue that the usual performance metrics of false accept and false reject rates are insufficient yardsticks for robust verification and propose new metrics against which we benchmark our system. [Copyright &y& Elsevier]

Abstract: In mixed model production, autonomous control method, which has been proved more responsive, robust and adaptive, is proposed to cope with rising complexity and dynamics. However, the implementation of autonomous control method is still a challenge. This paper focuses on implementing autonomous mixed model production control with wireless sensor/actuator networking technologies. The system architectures and design issues of wireless sensor/actuator network for autonomous mixed production control are presented, and a case study on which experiments are being made with an autonomous control application prototype shows its feasibility. [Copyright &y& Elsevier]

Abstract: In this paper, a co-processor centric multilayer runtime library (CellLib) was proposed by extending memory access library and enhancing the co-processor''s independency. The library supports both MPI and release-consistency-based Pthread programming model. The structure of multilayer runtime library and the flexibly extended memory access library not only make the model more efficient and scalable but also enhance the performance of irregular applications. In the model, while MPI programming interface enables large exiting MPI applications to be ported to the CBEA easily and facilitates the traditional parallel programming, the release-consistency-based Pthread programming interface offers an efficient task runtime library to both MPI and the system-level users who need full control over the architecture. The experimental results show that the proposed multilayer runtime library is suitable for various applications and can achieve better performance by using a profile based on optimizing technology built in memory access library. [Copyright &y& Elsevier]

Abstract: In order to study the satellite''s moving features and the size of stable reigns around the center equilibrium points of asteroid, 1:1 resonant orbits theory are applied in this paper. First the Hamilton function described by Delaunay variable is simplified to Schubart standard. Secondly the simplified mathematical model is used to discuss the form of orbital motion, vibration period of satellites which locate orbit the asteroid''s equilibrium points and the relationship between each other. And then Asteroid Vesta is taken as a simulation example to verify the correctness of these conclusions above. Finally, exploiting the properties of energy integral of Schubart standard, the formula of deducing the radius of stable region around the center points is given, which is also applied to analyze the properties of orbital motions both inside and outside of the stable region. The research in this article not only can help us better understand the equilibrium points of asteroids and the dynamical environments in the vicinity of which but also can it supply theoretical basis in designing the orbit around the equilibrium points around the asteroid. [Copyright &y& Elsevier]

Abstract: To the current problems in SCM experiment teaching, the necessity and principles of experiment reform are analyzed in this paper, and an experiment board is designed based on ISP download line. It presented the general structure diagram of the system, described the hard circuit and software design in details, and introduced the programming method with an example. This devices has the advantages such as low cost, easy to use and easy to carry, et al.. The practice showed that the device can greatly increase the student''s interest in SCM learning, so it can provide a good solution for experiment reform. [Copyright &y& Elsevier]

Abstract: With the process management of enterprise activities become mainstream. traditional process modeling and business process management exposed many shortcomings in Various aspects of business process elements of the internal relations. ARIS methodology design process management system comprehensively. And support the continuous improvement of business process management that Meeting the increasing customer quality requirements. In this paper, we use ARIS methodology as guide. using Rich client technology to create a process modeling and management platform and describing how to design and implement in detail. [Copyright &y& Elsevier]

Abstract: This paper proposed a software solution of GPS receiver quality inspection system based on the Simulated Signal Source. The GPS receiver quality inspection software of friendly man-machine interface, high efficiency and good stability is developed using language C#. Firstly, the functions of system are analyzed by the objective-oriented means. And the block diagram of whole software structure is given. Then the main function, data flow diagram, design effect and testing process of the Mathematical and Simulation Subsystem, Management and Control Subsystem and Testing and Evaluation Subsystem are detailed introduced. At last the quality inspection report on the Novatel dual-frequency receiver proved that the GPS receiver quality inspection software system is of good openness and high transplant ability. [Copyright &y& Elsevier]

Abstract: In this paper we discuss the optimal capital injections problem for the compound binomial risk model. Tahe value function is defined by maximizing the discounted value of the dividend payment minus the penalized discounted capital injection until the time of ruin. It is shown that the value function can be characterized by the Bellman''s equation. We find the optimal upper capital injection barrier and the optimal lower capital injection barrier. [Copyright &y& Elsevier]

Abstract: This paper presents a new steganographic scheme for 3D point cloud models using self-similarity segmentation. The new scheme segments the 3D point cloud model to patches using self-similarity measures, and generates the codebook. The representative patches and similar patches are then taken from the codebook for every similar patch chain as the reference patches and the message patches. Finally, every message point in the similar message patches which has the point-to-point correspondence with a certain reference point in the reference patch can embed at least three bits by shifting the message point from current point to the corresponding embedding position using space subdivision. Experimental results show that the proposed technique is secure, has high capacity and low distortion, and is robust against uniform affine transformations such as transformation, rotation, scaling. The technique can be considered as a side-match steganography and has proven to be a feasible alternative to other steganographic schemes for 3D point cloud model. [Copyright &y& Elsevier]

Abstract: Based on studying the running elements of three-level converter, the paper proposes a simple and accurate method of computing conduction and switching loss for three-level converter system. Analyses the factor of conduction and switching loss each other, also builds the experimentation of high power three-level converter and introduces a new double-fed experiment method to validating the accuracy of model. [Copyright &y& Elsevier]

Abstract: Based on the actual measurement environment and combined with IEEE 802.15.3a indoor model, a LOS doublecluster semi-deterministic statistical model was established to study the statistical characteristics of UWB channels, and the results obtained were consistent with the measured ones; with the help of the model established, the paper studied the impact of system resolution on the path intensity distribution, inspected and verified the measurement conclusions of actual measurement environment. [Copyright &y& Elsevier]

Abstract: This paper aimed to study the effect of paddle number and immersed radius ratio on water wheel performance. The water wheel models were tested for their performances in water channel. 3 HP pump was used to circulate the water with the velocity in the channel of 0.3 m/s. The torque load was varied and the rotational speed was measured then the maximum power was determined for each water wheel model. The paddle number was varied from 6 to 12. The immersed radius was varied from 0.05 to 0.15 m when the whole radius of water wheel was fixed at 0.20 m in order to obtain the immersed radius ratio of 0.25, 0.5 and 0.75. From the result, it was found that the highest performance occurred when the paddle number was 6 and the immersed radius ratio was 0.5. The torque load at the maximum power depended on the immersed radius ratio. And at the same immersed radius ratio, the 6, 8 and 12 paddle number water wheel models had the same torque load at the maximum power. [Copyright &y& Elsevier]

Abstract: This paper focuses on the performance and dynamic behavior of proton exchange membrane fuel cell (PEMFC) with 1.2kW under varies of an input load current. The mathematical model of PEMFC is developed based on energy, mass, and electrochemical equation. The some parameters in the model are kept constant. The performance and dynamic behaviors of PEMFC are determined by applied the variety of input load current with different types of input load current, such as saw-tooth, step, step input with dead time, and multi-step input load current. The results of model are compared to the experimental results. The results of the model show that the output cell voltages are suddenly dropped when the input load current have been increased and output cell voltage increased when decreased the input load current. This mathematical model can predict the dynamic behavior of the PEMFC when the input load currents have been changed. The experimental setups use 1.2kW of PEMFC with connected to electronic load device and can be operated the input load current from 0A to 500A. Hydrogen is used as a fuel at the anode side and air is used at the cathode side. The operating temperature is kept to be constant at room temperature. The experiments show that the output cell voltage is decreased when the input load current increased. There is some slightly different between the model and experiment results when compared at the same conditions. This is because of in the model we kept some parameter constant. The water generated during the process is tested under varying input load current from 1A to 30A. The dynamic behavior of the PEMFC under different types of input load current shows very well. [Copyright &y& Elsevier]

Abstract: Heat pump systems can be found in high number of applications. One of these is the production of domestic hot water. This paper presents a quasi-steady state simulation model to predict the performance of a simple air source heat pump water heater (ASHPWH). The mathematical model consists of submodels of the basic system components, namely, evaporator, condenser, compressor, and expansion valve. These submodels were built based on fundamental principles of heat transfer and thermodynamics. The model was coded into MATLAB software and used to predict system parameters of interest such as hot water temperature, evaporating and condensing pressures, heat rejected in the condenser, electric power input, heating seasonal performance factor, and coefficient of performance. [Copyright &y& Elsevier]

Abstract: Based on gray error GM (1,1) model, the paper proposed an improved error GM (1,1) model, and used this model to predict cultivated land in Yiyang. The results show that the improved error GM (1,1) model has high prediction accuracy, and better simulation results. And the results conform to the cultivated quantity change rule of Yiyang City, that is, the land area of Yiyang City, will appear in the next few years, modest growth trend, but the per capita arable land is still in the alert level of the United Nations. Therefore, protection of cultivated resources, rational utilization and protection of arable land are urgent tasks. [Copyright &y& Elsevier]

Abstract: In the current paper, CaCO3 precipitation process via CO2 absorption into aqueous solution of Ca(OH)2 was investigated in a stirred semi-batch reactor. Mathematical model describing the precipitation process was developed by considering the absorption and reaction kinetics as well as hydrodynamic conditions in the system. The model allows to simulate the concentration profiles of reactive species (CO2, Ca2+, OH−, CaCO3, HCO3 −, H+, CO32−) in the gas and liquid phase as well as to predict the rate of CaCO3 formation. The volumetric mass transfer coefficient, characterizing CO2 transfer performance from gas phase into Ca(OH)2 solution as well as rate constant of the CaCO3 precipitation reaction, were estimated based on the experimental data and the developed model. The CO2 mass transfer enhancement factor due to chemical reaction was also estimated. [Copyright &y& Elsevier]

Abstract: Studies have been carried out to show that there could be benefits in employing a hybrid of the post combustion capture and oxyfuel processes. The former is suited for retrofit purposes but involves an energy intensive solvent regeneration process. The oxyfuel process would result in high partial pressures of CO2 in the flue gas making separation easier. However, the Air Separation Unit is also energy intensive and significant modifications would have to be made on the power generation process. An enhanced- O2 coal power plant with post combustion CO2 capture would produce flue gas with reduced mass flow and higher CO2 partial pressures. The dynamic response of the downstream CO2 capture plant was studied in this paper. [Copyright &y& Elsevier]

Abstract: Successful large-scale deployment of CCS will require the build-up of commensurate infrastructure to transport CO2 from sources - e.g. power plants - to sinks - e.g. mature oil and gas fields. Research so far has mostly dealt with the techno-economic assessment of pre-defined CO2 value chains, which are typically country-specific and each connect a limited set of sources to a limited set of sinks. By contrast, our paper presents the JRC’s InfraCCS model, a tool that is capable of finding the optimal pipeline-based CO2 transmission network for a given set of sources and sinks. The InfraCCS model is herein applied to the case of CCS in Europe, in order to estimate the strategic benefits of joint optimisation at pan-European level compared to optimisation at the level of individual countries. [Copyright &y& Elsevier]

Abstract: A recurring topic in discussions on the implementation of carbon capture and storage are the uncertainties in the estimations of the storage potential. Many regions worldwide and also in Europe are indeed insufficiently explored for providing estimates that are sufficiently reliable for such purposes. In this paper we present a method through which reliable and quantitative estimates can be obtained for very poorly explored regions. This new approach is based on well-proven economic principles and expert input, which are combined with a semi-generic storage model. Evaluation of the Belgian storage potential results in an estimation of 15 Mt/y (95% C.I.: 3 to 35 Mt/y) when expressed as an annual injection rate, or 620Mt (95% C.I.: 150 to 1400 Mt) when expressed as the total storage capacity. This estimation is that of the actual, practical storage potential, rather than a theoretical overestimation which is obtained by other methods. The reliability of the method is theoretically and empirically verified. [Copyright &y& Elsevier]

Abstract: The effectiveness of CCS, i.e. its emission abatement potential in relation to the possibility of leakage of CO2 from geological reservoirs once this greenhouse gas has been stored artificially underground, will be among the main determinants of whether CCS can significantly contribute to a deep cut in global CO2 emissions. This paper presents an analysis of the economic and climatic implications of the large-scale use of CCS for reaching a stringent climate change control target, when geological CO2 leakage is accounted for. The natural scientific uncertainties regarding the rates of possible leakage of CO2 from geological reservoirs are likely to remain large for a long time to come. We present a concise analytical inspection, as well as an analysis with a more detailed integrated assessment model, proffering insight into the economics of geological CO2 storage and leakage. CO2 leakage lowers the value of CCS as climate mitigation option below the prevailing level of the CO2 tax. We therefore employ a definition for the effectiveness of temporary carbon storage as the net present value of the total stream of avoided emissions. We calculate the effectiveness of CCS under two leakage models (an exponential model with a constant seepage rate and a two-layer model with a bell-shaped time-dependent seepage rate) and with different assumptions regarding (1) the carbon tax growth rate relative to the interest rate and (2) the average CO2 storage life-time. We introduce the expression for the effectiveness of CCS in a top-down integrated assessment model that represents three main CO2 emission reduction options: energy savings, a carbon to non-carbon (renewable) energy transition and the use of CCS. We find CCS to remain a valuable option even with CO2 leakage of a few %/yr, well above the maximum seepage rates that we think are likely from a geo-scientific point of view. [Copyright &y& Elsevier]

Abstract: Reduction of carbon dioxide emissions into the atmosphere can be realized by the implementation of carbon dioxide capture and storage (CCS) technology. Successful implementation of CCS will depend on public acceptance of this technology. It has been argued that public trust in organizations involved in complex novel technologies influences risk/benefit perceptions and, consequentially, public acceptance of these technologies (e.g., Siegrist, 1999, 2000). This paper discusses whet her or not this model holds true in the context of CCS and whether or not it holds true for both integrity -based trust and comp etence-based trust. [Copyright &y& Elsevier]

Abstract: The scale of CO2 injection into the subsurface required to address CO2 atmospheric concentrations is unprecedented. Multiple injection sites injecting into multiple formations will create a large excess pressure zone extending far beyond the limited volume where CO2 is present. In a closed system, additional mass is accommodated by the compressibility of system components, an increase in fluid pressure, and possibly an uplift of the land surface. In an open system, as assumed in this analysis, another coping mechanism involves fluid flux out of the boundaries of the system, in which case the fresh-water-bearing outcrop areas, corresponding to the up-dip sections of the down-dip formations into which CO2 is injected, could be impacted. A preliminary study using a MODFLOW groundwater model extending far down-dip shows that injecting a large amount of fluid does have an impact some distance away from the injection area but most likely only in localized areas. A major assumption of this preliminary work was that multiphase processes do not matter some distance away from the injection zones. In a second step, presented in this paper, to demonstrate that a simplified model can yield results as useful as those of a more sophisticated multiphase-flow compositional model, we model the same system using CMG-GEM software. Because the chosen software lacks the ability to deal easily with unconfined water flow, we compare fluxes through time, as given by MODFLOW and CMG-GEM models at the confined/unconfined interface. [Copyright &y& Elsevier]

Abstract: The permeability of the coal seam is the main petrophysical property controlling the performance of the ECBM operation, since it affects both the CO2 injection and CH4 recovery. In the present paper, coal swelling of intact coal samples is studied both under unconstrained and constrained conditions. Unconstrained swelling experiments are performed in a view cell under a static high pressure gas atmosphere, whereas gas injection experiments are carried out in a flow cell, where the sample is subjected to a given hydrostatic confinement. Both experiments are performed by using different gases, namely He, CO2, CH4 and N2, and under typical coal seam conditions, i.e. at high pressure and at 45 ∘C. The results of the unconstrained coal sample showed that swelling increases monotonically with pressure up to a few percents for adsorbing gases, with CO2 swelling coal more than CH4 that swells more than N2, whereas for helium, a non-adsorbing gas, volume changes are negligible. The results of the flow experiments were successfully described using a mathematical model consisting of mass balances accounting for gas flow and adsorption, and mechanical constitutive equations for the description of porosity and permeability changes during injection. Results showed increase in permeability with decreasing effective pressure on the sample. Moreover, when CO2 is used a permeability reduction was observed compared to Helium, which can be explained by taking into account the effects of swelling on the flow dynamics. [Copyright &y& Elsevier]

Abstract: In this paper we present a spatial optimization model that comprehensively models carbon capture and s torage (CCS) infrastructure, from source -to -sink. The model optimally and simultaneously chooses at which sources and how much CO2 should be captured, at which reservoirs (or sinks) and how much CO2 should be injected and stored, where a pipeline network should be constructed and at what capacity, and how to distribute CO2 among the networked sources and reservoirs. A key contribution of the model is the ability to link sources and reservoirs using a realistic and capacitated pipeline network. [Copyright &y& Elsevier]

Abstract: Metal organic frameworks (MOFs) have emerged as one of the more interesting classes of materials for adsorption based separation of CO2 from other gases in exhaust mixtures. To improve efficiency in developing structure property relationships, we have developed a general methodology to model, based on molecular grand canonical Monte Carlo (GCMC) methods, the adsorption of CO2 and other gases within these framework structures. This approach also provides insight into the relative importance of various mechanisms of CO2 adsorption. So far, we have demonstrated good correlation between calculated and experimental isotherms for a number of synthetic MOFs. Through systematic (virtual) variation of structural motifs we are striving to develop an und erstanding of structure-property relationships that will enable the identification, and hence the design, of optimum materials for CO2 separation from various exhaust gas mixtures and under varied conditions of temperature and pressure. The paper present s details of the approach, a comparison between predicted and experimentally determined isotherms, and preliminary identification of some preferred structural features. [Copyright &y& Elsevier]

Abstract: There is strong world-wide interest in developing new and improved processes for post-combustion capture of CO2, usually using chemical absorption. Developers of new processes make positive claims for their proposals in terms of low energy consumption, but these are usually difficult to validate. This paper demonstrates that rigorous application of thermodynamic analysis and process simulation provides a powerful way to quantitatively evaluate the energy requirements of CO2-capture processes by applying this methodology to the analysis of the chilled-ammonia process. [Copyright &y& Elsevier]

Abstract: In this paper a rector model is presented for a SE-SMR reactor. The reactor model comprises simplified mathematical representation of the flow regime, differential equations for mass and heat transfer, sub-model for chemical reaction kinetics and absorption equilibria. The model was used to investigate various operational modes for the reformer as well as for comparison of the reformer performance with use of various sorbents (Li4SO4,Na2ZrO3,CaO). A semi-empirical model for apparent reaction kinetics of dolomite was developed based on thermogravimetrical analysis whereas the reaction kinetics for the other types of sorbents was taken from literature. [Copyright &y& Elsevier]