Dynamic control

Grid connection of renewable energy sources (RESs), such as wind and solar, is becoming today an important form of distributed generation (DG). The penetration of these DG units into electrical microgrids (MGs) is growing rapidly, enabling reaching high percentage of the installed generating capacity. However, the fluctuating and intermittent nature of this renewable generation causes variations of power flow that can significantly affect the stability and operation of the electrical grid. To overcome these problems, short-term distributed energy storage (DES) systems based on advanced technologies, such as superconducting magnetic energy storage (SMES), supercapacitor (or ultracapacitor) energy storage (SCES or UCES) and flywheel energy storage (FES), arise as a potential alternative in order to balance any instantaneous mismatch between supply and demand in the microgrid. This paper is intended to offer a major insight into the emerging energy storage technologies for smart microgrid applications. The work provides a unique comprehensive analysis of both the modeling and the control design of leading emerging DES devices.

Orchestrated modulation of cell adhesion is essential for development and homeostasis in multicellular organisms. It optimizes embedding of the cell in its dynamic environment and facilitates appropriate cell responses and intercellular communication. Chronic disturbance of this delicate equilibrium causes defects in tissue architecture and sometimes cancer. In tumor cell biology, dynamic control of adhesion molecules is important to proceed through the metastatic cascade and to allow cell release from the primary tumor, invasion of the surrounding matrix, intravasation and adhesion to vascular endothelial cells to facilitate extravasation. Intertwined and multiple adhesive interactions rather than individual interactions presumably play critical roles in neoplastic development. Yet, knowledge of the contribution of each individual adhesion molecule is essential to unravel this network of interactions. This review will focus on activated leukocyte cell adhesion molecule (ALCAM/CD166) and its role in human melanoma progression. It is hypothesized that ALCAM may function as a cell surface sensor to register local growth saturation and to regulate cellular signaling and dynamic responses.

Construction project control aims to effectively obtain real-time information and enhance dynamic control by utilizing information sharing and connecting involved participants of the projects to reduce construction conflicts and project delays. However, extending the construction project control system to job sites is not considered efficient because using notebooks in a harsh environment like a construction site is not particularly a conventional practice. Meanwhile, paper-based documents of the site processes are ineffective and cannot get the quick response from the office and project control center. Integrating promising information technologies such as personal digital assistants (PDA), bar code scanning, and data entry mechanisms, can be extremely useful in improving the effectiveness and convenience of information flow in construction supply chain control systems. Bar code scanning is appropriate for several construction applications, providing cost savings through increased speed and accuracy of data entry. This article demonstrates the effectiveness of a bar-code-enabled PDA application, called the mobile construction supply chain management

Abstract—This paper reports on the control structure of the pneumatic biped Lucy. The robot is actuated with pleated pneumatic artificial muscles, which have interesting characteristics that can be exploited for legged machines. They have a high power to weight ratio, an ...

A new technique for constructing dynamic equivalents of power systems is developed. The method identifies the important modes of the system utilising a performance index based on the notions of controllability and observability. The system state variables corresponding to the retained modes are identified by inspection of the elements of the sentivity matrix relating the eigenvalues to the state variables. The suitability of the method for obtaining reduced-order models of power systems for dynamic-control purposes is demonstrated on a single-machine infinite-bus system. Several reduced-order models are produced and their accuracy discussed.

With rapid technological advances in network infrastructure, programming languages, compatible component interfaces and so many more areas, today the computational Grid has evolved with the potential of seamless aggregation, integration and interactions. This has made it possible to conceive a new generation of realistic, scientific and engineering simulations of complex physical phenomenon. These applications will symbiotically and opportunistically combine computations, experiments, observations, and real-time data, and will provide important insights into complex phenomena. However, the phenomena being modeled are inherently complex, multi-phased, multi-scaled, dynamic and heterogeneous (in time space and state). Furthermore, their implementations involve multiple researchers with scores of models, hundreds of components and dynamic compositions and interactions between these components. The underlying Grid infrastructure is similarly heterogeneous and dynamic, globally aggregating large numbers of independent computing and communication resources, data stores and sensor networks. The combination of the two results in application development, configuration and management complexities that break current paradigms that are based on passive components and static compositions. In fact, we have reached a level of complexity, heterogeneity, and dynamism that our programming environments and infrastructure are becoming unmanageable/insecure .

The paper presents the design and evaluation of PECOS, a PreEmptive COntrol Signature technique for on-line detection of control flow errors. The technique uses assertions that can be embedded in the assembly language code and that are triggered by control flow instructions in the code. The PECOS target error model is any corruption that causes the application to take an incorrect control flow path. This includes corrupted control flow instructions as well as any other corruption that subsequently affects the control flow. The proposed technique is shown to handle both static and dynamic control flow constructs. PECOS is evaluated through software-based error injection-both directed control flow injections and random injections into the text segment of the running application. The injected errors model the impact of failures in the address and data lines between a processor and memory. The effectiveness of PECOS is illustrated on a real application: the Dynamic Host Configuration Protocol (DHCP) server. It is shown that PECOS detects more than 87% of control flow errors, reducing the incidence of fail-silence violations from 3.6% to 0.1% and of process crashes from 54.6% to 7.1%. Performance studies show a degradation of 15-29% with instrumentation of the entire DHCP server, and a degradation of 5-13% with instrumentation of only the critical DHCP protocol engine.

Electrochromic evacuated advanced glazing has been developed, combining optimum dynamic control of the solar radiation penetrating into buildings with a high degree of thermal insulation. This was achieved by the optimisation of the electrochromic device materials (electrochromic, ion storage, protective layers, transparent conductors and polymer electrolytes) and by the refinement of a sealing method for evacuated glazing. Electrochromic evacuated glazing prototypes with dimensions up to 40 cm  40 cm have been fabricated using vacuum techniques and chemical methods. The prototypes exhibit excellent optical and thermal performance, with a contrast ratio up to 1:32 (visible dynamic transmittance range T lum,bleached = 63% and T lum,colored = 2%), coloration efficiency up to 92 cm 2 /C and mid-pane U-values as low as 0.86 W m À2 K À1 . Their durability in relation to real working environmental conditions has been assessed through indoor and outdoor testing. Such a glazing can be used in building applications to improve occupant thermal comfort, contribute to a reduction in space heating and cooling loads and allow for increased areas of fenestration thereby reducing artificial lighting loads. These factors reduce the energy demand for the building and therefore contribute to the reduction of carbon dioxide emissions. #

This thesis explores computation mobility. We view mobility, the selection of an execution environment, as an attribute of a computation. To capture this attribute, we introduce a novel programming abstraction, which we call a mobility attribute, that specifies where computations should occur within a distributed system. Programmers dynamically bind mobility attributes to program components, nonempty sets of functions and their state. Once bound to a component, mobility attributes apply prior to each execution of that component.

{ Whenever a sensor is mounted on a robot hand it is important t o k n o w the relationship between the sensor and the hand. The problem of determining this relationship is referred to as the hand-eye calibration problem. Hand-eye calibration is important in at least two types of tasks: (i) map sensor centered measurements into the robot workspace frame and (ii) allow the robot to precisely move the sensor. In the past some solutions were proposed in the particular case of the sensor being a TV camera. With almost no exception, all existing solutions attempt to solve a homogeneous matrix equation of the form AX = X B . This paper has the following main contributions. First we show that there are two possible formulations of the hand-eye calibration problem. One formulation is the classical one that we just mentioned. A second formulation takes the form of the following homogeneous matrix equation: M Y= M 0 Y B . The advantage of the latter formulation is that the extrinsic and intrinsic parameters of the camera need not be made explicit. Indeed, this formulation directly uses the 3 4 perspective matrices (M and M 0 ) associated with 2 positions of the camera with respect to the calibration frame. Moreover, this formulation together with the classical one cover a wider range of camera-based sensors to be calibrated with respect to the robot hand: single scan-line cameras, stereo heads, range nders, etc. Second, we develop a common mathematical framework to solve for the hand-eye calibration problem using either of the two formulations. We represent rotation by a unit quaternion. We present two methods, (i) a closed-form solution for solving for rotation using unit quaternions and then solving for translation and (ii) a non-linear technique for simultaneously solving for rotation and translation. Third, we perform a stability analysis both for our two methods and for the classical linear method developed by Tsai & Lenz TL89]. This analysis allows the comparison of the three methods. In the light of this comparison, the non-linear optimization method, that solves for rotation and translation simultaneously, seems to be the most robust one with respect to noise and to measurement errors.

In this paper, a review of past and recent developments in the dynamics of flexible multibody systems is presented. The objective is to review some of the basic approaches used in the computer aided kinematic and dynamic analysis of flexible mechanical systems, and to identify future directions in this research area. Among the formulations reviewed in this paper are the floating frame of reference formulation, the finite element incremental methods, large rotation vector formulations, the finite segment method, and the linear theory of elastodynamics. Linearization of the flexible multibody equations that results from the use of the incremental finite element formulations is discussed. Because of space limitations, it is impossible to list all the contributions made in this important area. The reader, however, can find more references by consulting the list of articles and books cited at the end of the paper. Furthermore, the numerical procedures used for solving the differential and algebraic equations of flexible multibody systems are not discussed in this paper since these procedures are similar to the techniques used in rigid body dynamics. More details about these numerical procedures as well as the roots and perspectives of multibody system dynamics are discussed in a companion review by Schiehlen . Future research areas in flexible multibody dynamics are identified as establishing the relationship between different formulations, contact and impact dynamics, control-structure interaction, use of modal identification and experimental methods in flexible multibody simulations, application of flexible multibody techniques to computer graphics, numerical issues, and large deformation problem. Establishing the relationship between different flexible multibody formulations is an important issue since there is a need to clearly define the assumptions and approximations underlying each formulation. This will allow us to establish guidelines and criteria that define the limitations of each approach used in flexible multibody dynamics. This task can now be accomplished by using the absolute nodal coordinate formulation which was recently introduced for the large deformation analysis of flexible multibody systems.

Over the last two decades, significant research effort has been directed towards developing vehicle transmissions that reduce the energy consumption of an automobile. This effort has been a direct consequence of the growing environmental concern imposing the directives of reduced exhaust emissions and increased vehicle efficiency on current vehicle manufacturers and users. A continuously variable transmission (CVT) offers a continuum of gear ratios between desired limits, which consequently enhances the fuel economy and dynamic performance of a vehicle by better matching the engine operating conditions to the variable driving scenarios. Although a CVT plays a crucial role in the plan to improve vehicle fuel economy, its complete potential has not been realized in a mass-production vehicle. The current paper reviews the state-of-the-art research on dynamic modeling and control of friction-limited continuously variable transmissions. The basic concepts, mathematical models, and computational schemes are extensively discussed. Challenges and critical issues for future research on modeling and control of such CVTs are also discussed.

The Due to their advantage of high speed, accuracy and repeatability, robot manipulators have become major component of manufacturing industries and even now a days they become part of routine life. Two link robot manipulator is a very basic classical and simple example of robot followed in understanding of basic fundamentals of robotic manipulator. The equation of motion for two link robot is a nonlinear differential equation. For higher degrees of freedom, as the closed form solutions are very difficult we have to use numerical solution. Here we focused mainly on control of robot manipulator to get the desired position using combination of two classical methods PID and computed torque control method after deriving the equation of motion. For the same simulation is represented using MATLAB and compared with computed torque control method.

Distillation of close-boiling mixtures, such as propylene-propane and ethyl benzene-styrene systems, is an energy intensive process. Vapor recompression techniques and heat pumping-assisted columns have been adopted for such applications for their high potential of energy savings. In direct vapor recompression columns, the vapors leaving the top of the column are compressed, and in the reboiler of the same column, these vapors are condensed to provide heat for vapor generation. Internal heat integrated distillation columns or iHIDiCs are new developments employing the same concept of vapor recompression. These new column configurations can have significantly lower energy demands than common vapor recompression units. In iHIDiCs, rectifying section is operated at a higher pressure (i.e. higher temperature) than in stripping, and therefore its heat can be used to generate vapor in stripping section. So far, design of these column configurations is performed based on engineering experience, simulation or experimental studies on given cases, including dynamic control simulations. Within previous and most recent research efforts on iHIDiCs, there exist no generalized design methods or systematic approaches for design of these internal integrated distillation columns.

Design of smart journal-bearing systems is an important issue that opens up the possibility for semiactive dynamic control of bearing behavior. Recent studies show that there is an increasing interest in designing hydrodynamically lubricated bearings using electro-rheological fluids (ERFs) or magnetorheological fluids (MRFs). Both smart fluids behave like Bingham fluids, and thus the Bingham plastic model is used to describe the grease and the electro-rheological (ER) and magneto-rheological (MR) fluids behavior of the non-Newtonian fluid flow. The performance characteristics of a hydrodynamic journal bearing lubricated with a Bingham fluid are derived by means of three-dimensional computational fluid dynamics (3-D CFD) analysis. The FLUENT software package is used to calculate the hydrodynamic balance of the journal using the so-called ''dynamic mesh'' technique. The results obtained from the developed 3-D CFD model are found to be in very good agreement with experimental and analytical data from previous investigations on Bingham fluids.

This paper presents an embedded energy share method between the high energy storage system (battery) and the auxiliary energy storage system such as supercapacitors (SC). Using the SC and battery with a good strategy for energy management improves the performance of hybrid electric vehicles (HEVs). The SC modules are dimensioned for peak power requirement, and the battery's module ensures the average power of HEVs. The battery module is connected to dc-bus through a dc/dc converter for the first topology and without a converter for the second configuration. Buck-boost converters are used between the SC and the dc-bus to manage the available energy for all topologies. The originality of this paper stems from its focus on the control methods of the dc-bus voltage and currents, which use adjustable polynomial controllers (correctors based on polynomial approach). These methods are implemented in the PIC18F4431 microcontroller which ensures analog to digital conversion, and the pulsewidth modulation signals generation for dc/dc converters. Due to cost and available components, such as the power semiconductors (IGBT) and the battery, the experimental tests benches are carried out in reduced scale. Through some simulations and experimental results, the performance of the proposed control is shown and analyzed.

In this article, a review on parallel kinematic machine dynamic control is performed. It is shown that the classical control strategies from serial robotics generally used for parallel kinematic machine have to be thought again. Indeed, it is first shown that the joint space control is not relevant for these mechanisms for several reasons such as mechanical behaviour or computational efficiency. Consequently, the Cartesian space control should be preferred over the joint space one. Nevertheless, some modification to the well-known Cartesian space control strategies of serial robotics are proposed to perfectly suit them to parallel kinematic machines, particularly a solution using an exteroceptive measure of the end-effector pose. The expected improvement in terms of accuracy, stability and robustness are discussed. A comparison between the main presented strategies is finally performed both in simulation and experiments.

A dynamic object is an object whose properties change over time. A static object is an object whose properties do not change over time. Given such an idealization, the notion of 'static' lies at an extreme end of the spectrum of temporal relations between objects and properties. Indeed, modern physics tells us that no objects are truly static. Nevertheless, many of our physical, computational, and metaphysical theories turn a blind eye to the role of time, often for practical reasons. So, perhaps it is not surprising that in the philosophy of mind -where physical, computational, and metaphysical theories meet -there has been a consistent tendancy to articulate theories that consider function and time independently. As a result, contemporary theories in cognitive science consider time unsystematically (see the next section for specific examples). In this chapter, I suggest that the problem with this 'ad hocery' is that the systems we are trying to characterize are real-time systems, whose real-time performance demands principled explanation (a point on which many of these same contemporary theorists agree). After a discussion of the importance and roots of dynamics in cognitive theorizing, I describe the role of time in each of the three main approaches to cognitive science: symbolicism, connectionism and dynamicism. Subsequently, I outline a recently proposed method, the Neural Engineering Framework (NEF), that, unlike past approaches, permits a principled integration of dynamics into biologically realistic models of high-level cognition. After briefly presenting a model, BioSLIE, that demonstrates this integration using the NEF, I argue that this approach alone is in a position to properly integrate dynamics, biological realism, and high-level cognition.

This paper describes analysis of steady motions for underwater gliders, a type of highly efficient underwater vehicle which uses gravity for propulsion. Underwater gliders are winged underwater vehicles which locomote by modulating their buoyancy and their attitude. Several such vehicles have been developed and have proven their worth as efficient long-distance, long-duration ocean sampling platforms. To date, the primary emphasis in underwater glider development has been on locomotive efficiency; maneuverability has been a secondary concern. The ultimate aim of our research is to develop optimal motion control strategies which enhance the natural locomotive efficiency of underwater gliders by minimizing the energy expended by the control system. Ambitious applications such as persistent undersea surveillance require not only efficient vehicles, but efficient guidance and control schemes. This technical report aims to develop a better understanding of glider maneuverability, particularly with regard to turning motions. As a preliminary step, we develop an approximate analytical expression for steady turning motion for a realistic glider model. The problem is formulated in terms of regular perturbation theory, with the vehicle turn rate as the perturbation parameter. The resulting solution exhibits a special structure that allows one to apply existing optimal path planning results for planar mobile robots. The ultimate result is a simple, energy-efficient motion control method for underwater gliders.

This paper explores the problems associated with the multicasting of continuous media to support multimedia group applications. The interaction between multicasting and the delivery of multiple time-correlated continuousmedia streams with real-time delay requirements poses various new and interesting problems in research on communication protocols and architectures. We describe these problems, and identify where the opportunities are for effective solutions, all in the context of providing an overview of the current state of research in multimedia multicasting. The issues we discuss include quality of service, resource reservations, routing, error and traffic control, heterogeneity, and the use of hierarchical coding and open-loop control techniques.

The concept of a medical parallel manipulator applicable to chest compression in the process of cardiopulmonary resuscitation (CPR) is proposed in this paper. According to the requirement of CPR action, a three-prismatic-universal-universal (3-PUU) translational parallel manipulator (TPM) is designed for such applications. And a thorough analysis involving the issues of kinematics, dynamics, and control have been performed for the 3-PUU TPM. Not only the inverse and forward kinematics problems are solved in closed-form, but also the Jacobian matrix is derived analytically, along with the manipulator workspace generated in view of the physical constraints imposed by mechanical joints. Based on the principle of virtual work with a simplifying hypothesis adopted, the dynamic modeling is performed, and dynamic control utilizing computed torque method is implemented, at last the simulation results illustrate the well performance of the control algorithm. The research work provide a sound base for the development of a medical manipulator to assist in CPR operation.

High speed unmanned ground vehicles evolving on natural terrains can exhibit a significant slip and skid. An estimation of both friction and traction forces can allow to achieve a better control. In order to implement a control architecture based on the vehicle dynamic model and the wheel-soil interaction model, the knowledge of the wheels slip rate is required. The wheel angular velocities can be precisely measured. But the true measurement of the ground speed of the vehicle is much more challenging. A low-cost Doppler radar is used, in conjunction with an accelerometer, to obtain the ground speed. Thus, the knowledge of the slip rate allows us to set up an in-situ procedure for the estimation of soil parameters that is based on the measurement of the motors torques. A wheel slippage controler has also been implemented, which is a first step toward high-level dynamic control.

Data from field observations and numerical model simulations are used to understand and quantify the pathways by which passive tracers penetrate into the Black Sea intermediate and deep layers. Chlorofluorocarbon (CFC) concentrations measured during the1988 R.V. Knorr cruise show strong decrease with increasing density in the Black Sea and illustrate the very slow rate of ventilation of deep water in this basin. We develop a 3D numerical model based on the Modular Ocean Model (MOM), and calibrate it in a way to produce consistent simulations of observed temperature, salinity and CFCs. One important feature is the implementation of a special parameterization for convection, which is an alternative of the convective adjustment in MOM and handles the penetration of the Bosporus plume into the halocline. The model forcing includes interannually variable wind, heat and water fluxes constructed from Comprehensive Ocean-Atmosphere Data Set and ECMWF atmospheric analysis data and river runoff data. The analysis of observations and simulated data are focused on correlations between thermohaline and tracer fields, dynamic control of ventilation, and the relative contributions of sources at the sea surface and outflow from the Bosporus Strait in the formation of intermediate and deep waters. A simple theory is developed which incorporates the outflow from the strait along with the vertical circulation (vertical turbulent mixing and Ekman upwelling) and reveals their mutual adjustment. The analyses of simulated and observed CFCs demonstrate that most of the CFC penetrating the deep layers has its source at the sea surface within the Black Sea rather than from the Marmara Sea via the Bosporus undercurrent. Under present-day conditions, the surface CFC signals have reached only the upper halocline. Intrusions below 600 m are not simulated. The major pathways of penetration of CFCs are associated with cold-water ARTICLE IN PRESS www.elsevier.com/locate/dsr 0967-0637/$ -see front matter r mass formation sites, Bosporus effluent, as well as with the diapycnal mixing in the area of Rim Current. Future CFC sampling strategies coherent with the unique conditions in the Black Sea are discussed. r

A not trivial problem in bipedal robot walking is the instability produced by violent transitions between the different walk phases. In this work a dynamic algorithm to control a biped robot is proposed. The algorithm is based on cubic polynomial interpolation of the initial conditions for the robot's position, velocity and acceleration. This guarantee a constant velocity an a smooth transition in the control trajectories. The algorithm was successfully probed in the bipedal robot "Dany walker" designed at the Freie Universität Berlin.

In this paper, we present a decentralized dynamic control algorithm for a robot collective consisting of multiple nonholonomic wheeled mobile manipulators (NH-WMMs) capable of cooperatively transporting a common payload. In this algorithm, the high level controller deals with motion/force control of the payload, at the same time distributes the motion/force task into individual agents by grasp description matrix. In each individual agent, the low level controller decomposes the system dynamics into decoupled task space (end-effector motions/forces) and a dynamically-consistent null-space (internal motions/forces) component. The agent level control algorithm facilitates the prioritized operational task accomplishment with the end-effector impedance-mode controller and secondary null-space control. The scalability and modularity is guaranteed upon the decentralized control architecture. Numerical simulations are performed for a 2-NH-WMM system carrying a payload (with/without uncertainty) to validate this approach.

This paper presents supercapacitor (SCAP) and battery modeling with an original energy management strategy in a hybrid storage technology. The studied dc power supply is composed of SCAPs and batteries. SCAPs are dimensioned for peak power requirement, and batteries provide the power in steady state. A bidirectional dc/dc converter is used between SCAPs and the dc bus. Batteries are directly connected to the dc bus. The originality of this study is focused on SCAP behavior modeling and energy management strategy. The proposed strategy is based on a polynomial (RST) controller. For reasons of cost and existing components (not optimized) such as batteries and semiconductors, the experimental test benches are designed in reduced scale. The characterized packs of SCAPs include two modules of ten cells in series for each one and present a maximum voltage of 27 V. The proposed strategy is implemented on a PIC18F4431 microcontroller for two dc/dc converter topology controls. Experimental and simulation results obtained from the polynomial control strategy are presented, analyzed, and compared with that of classical proportional-integral control.

This paper describes a modelling and dynamic control design process applicable to the development of fuel cell electric vehicles (FCEVs) and hybrid electric vehicles (HEVs). After an introduction to advanced propulsion technologies the development of FCEVat DaimlerChrysler is described, followed by a discussion on hydrogen as a fuel for FCEV and the challenges related to hydrogen storage. It is essential for advanced vehicles to obtain a range comparable to that of mass production vehicles sold today. Thus, there is a strong need to operate such vehicles with high efficiency and maximize the energy stored onboard a vehicle. A stochastic dynamic programming algorithm was developed and applied to the energy management of this FCEV, which allow fuel economy optimisation while keeping a good driveability.

Increasing complexity and interdependency in manufacturing enterprises require an agile manufacturing paradigm. This paper considers a dynamic control approach for linking manufacturing strategy with market strategy through a reconfigurable manufacturing planning and control (MPC) system to support agility in this context. A comprehensive MPC model capable of adopting different MPC strategies through distributed controllers of inventory, capacity, and WIP is presented. A hierarchical supervisory controller (referred to as decision logic unit, DLU) that intakes the high-level strategic market decisions and constraints together with feedback of the current manufacturing system state (WIP, production, and inventory levels) and optimally manages the distributed controllers is introduced. The DLU architecture with its three layers and their different functionalities is discussed showing how they link the higher management level to the operational level to satisfy the required demand. A case study for an automatic PCB assembly factory is implemented to demonstrate the applicability of the whole approach. In addition, a comparative cost analysis study is carried out to compare between the developed agile MPC system and classical-inventory- and capacity-based MPC policies in response to different demand patterns. Results showed that the developed agile MPC policy is as cost effective as the inventory-based MPC policy in demand patterns with steady trends, as cost effective as capacity-based MPC in turbulent demand patterns, and far superior than both classical MPC polices in mixed-demand patterns.

This paper extends previous research on two approaches to human-centred automation: (1) intermediate levels of automation (LOAs) for maintaining operator involvement in complex systems control and facilitating situation awareness; and (2) adaptive automation (AA) for managing operator workload through dynamic control allocations between the human and machine over time. Some empirical research has been conducted to examine LOA and AA independently, with the objective of detailing a theory of human-centred automation. Unfortunately, no previous work has studied the interaction of these two approaches, nor has any research attempted to systematically determine which LOAs should be used in adaptive systems and how certain types of dynamic function allocations should be scheduled over time. The present research briefly reviews the theory of humancentred automation and LOA and AA approaches. Building on this background, an initial study was presented that attempts to address the conjuncture of these two approaches to human-centred automation. An experiment was conducted in which a dual-task scenario was used to assess the performance, SA and workload effects of low, intermediate and high LOAs, which were dynamically allocated (as part of an AA strategy) during manual system control for various cycle times comprising 20, 40 and 60% of task time. The LOA and automation allocation cycle time (AACT) combinations were compared to completely manual control and fully automated control of a dynamic control task performed in conjunction with an embedded secondary monitoring task. Results revealed LOA to be the driving factor in determining primary task performance and SA. Low-level automation produced superior performance and intermediate LOAs facilitated higher SA, but this was not associated with improved performance or reduced workload. The AACT was the driving factor in perceptions of primary task workload and secondary task performance. When a greater percentage of primary task time was automated, operator perceptual resources were freed-up and monitoring performance on the secondary task improved. Longer automation cycle times than have previously been studied may have benefits for overall human-machine system performance. The combined effect of LOA and AA on all measures did not appear to be 'additive' in nature. That is, the LOA producing the best performance (low level automation) did not do so at the AACT, which produced superior performance (maximum cycle time). In general, the results are supportive of intermediate LOAs and AA as approaches to human-centred automation, but each appears to provide different benefits to human-machine system performance. This work provides additional information for a developing theory of human-centred automation.

Bigtable is a distributed storage system for managing structured data that is designed to scale to a very large size: petabytes of data across thousands of commodity servers. Many projects at Google store data in Bigtable, including web indexing, Google Earth, and Google ...

The effective and reliable use of existing transmission lines are critically important because high-voltage transmission networks met enormous power demands are very expensive investments in terms of their costs. Flexible Alternating Current Transmission Systems (FACTS) are quite efficient to control the power flow of the transmission lines and increase the current capacity of system. Unified Power Flow Controller (UPFC) is the more efficient among FACTS equipments which have the potential to increase the power flow and stability of the transmission line. This paper develops new control approaches for both series and shunt inverters of UPFC. The proposed controller algorithms of shunt and series inverters are based on fuzzy logic controller and rotating orthogonal-coordinate method, respectively. Dynamic control of power flow using proposed UPFC is analyzed as mathematically. Power System Computer-Aided Design (PSCAD) is used to simulate the system and test UPFC in the simulation environment. The test results are presented to show the increased stability of the system and improved dynamic response of UPFC during faults occurred in the transmission line. Crown

It is shown that the vehicle dynamic control (VDC) system can improve the vehicle handling and active safety of driver and passengers considerably. The control of vehicle yaw moment through differential braking, based on the vehicle dynamic state feedbacks, is a traditional way of VDC. In this study, a new VDC system for a four motorized-wheels electric vehicle has been developed, for which the traction of each wheel can be controlled individually. Using this feature, the new VDC system provides the desired tractive force of vehicle and the desired external yaw moment through the integrated control of wheel motors. The structure of the control system is a multilayer type, which has been developed by using independent controllers, designed in accordance with the appropriate theories.

A dynamic control system design has been a great demand in the control engineering community, with many applications particularly in the field of flight control. This paper presents investigations into the development of a dynamic nonlinear inverse-model based control of a twin rotor multi-input multi-output system (TRMS). The TRMS is an aerodynamic test rig representing the control challenges of modern air vehicle. A model inversion control with the developed adaptive model is applied to the system. An adaptive neuro-fuzzy inference system (ANFIS) is augmented with the control system to improve the control response. To demonstrate the applicability of the methods, a simulated hovering motion of the TRMS, derived from experimental data is considered in order to evaluate the tracking properties and robustness capacities of the inverse- model control technique.

Activated Leukocyte Cell Adhesion Molecule (ALCAM/CD166), is expressed on osteoblasts (OB) and hematopoietic stem cells (HSC) residing in the hematopoietic niche, and may have important regulatory roles in bone formation. Because HSC numbers are reduced 77% in CD166(-/-) mice, we hypothesized that changes in bone phenotype and consequently the endosteal niche may partially be responsible for this alteration. Therefore, we investigated bone phenotype and OB function in CD166(-/-) mice. Although osteoclastic measures were not affected by loss of CD166, CD166(-/-) mice exhibited a modest increase in trabecular bone fraction (42%), and increases in osteoid deposition (72%), OB number (60%), and bone formation rate (152%). Cortical bone geometry was altered in CD166(-/-) mice resulting in up to 81% and 49% increases in stiffness and ultimate force, respectively. CD166(-/-) OB displayed elevated alkaline phosphatase (ALP) activity and mineralization, and increased mRNA expression of Fra 1...

Public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing this collection of information. Send comments regarding this burden estimate or any other aspect of this collection of information, including suggestions for reducing this burden to Department of Defense, Washington Headquarters Services, Directorate for Information Operations and Reports (0704-0188), 1215 Jefferson Davis Highway, Suite 1204, Arlington, VA 22202-4302. Respondents should be aware that notwithstanding any other provision of law, no person shall be subject to any penalty for failing to comply with a collection of information if it does not display a currently valid OMB control number.

Many modern pharmaceutical therapies such as vaccines and macromolecular drugs benefit from transdermal delivery. Conventional transdermal drug delivery via hypodermic needles causes pain, noncompliance, and potential contamination. Alternative transdermal strategies that deliver drugs in a quick, reliable, painless, and inexpensive way are needed. Jet injectors, which deliver drugs through the skin using a high-speed stream of liquid propelled by compressed springs or gasses, provide a needle-free method of trandermal drug delivery. However, poor reliability as well as painful bruising and bleeding characterize these devices, due in part to the high and constant jet velocity with which drugs are delivered. Toward improved reliability and reduced pain, we have developed a jet injector capable of dynamic control of jet velocity during a single injection pulse. Using this device, we demonstrate that temporal control of jet velocity leads to independent control of penetration depth, by adjusting time at high velocity, and delivered dose, by adjusting time at low velocity, in model materials. This dynamic control of jet velocity creates the potential for better control of needle-free injections, as demonstrated through injection studies on whole ex vivo human skin samples.

With multiple air-interface support capabilities and higher cell densities, future cellular networks will offer a diverse spectrum of user services. The resulting dynamics in traffic load and resource demand will challenge present control loop algorithms. In addition, frequent upgrades in the network infrastructure will substantially increase the network operation costs if done using current optimization methodology. This motivates the development of dynamic control algorithms that can automatically adjust the network to changes in both traffic and network conditions and autonomously adapt when new cells are added to the system. Bell Labs is pursuing efforts to realize such algorithms with research on near-term approaches that benefit present third-generation (3G) systems and the development of control features for future networks that perform dynamic parameter adjustment across protocol layers. In this paper, we describe the development of conceptual approaches, algorithms, modeling, simulation, and real-time measurements that provide the foundation for future dynamic network optimization techniques. © 2005 Lucent Technologies Inc.