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Molecular simulations of soft matter systems have been performed in recent years using a variety of systematically coarse-grained models. With these models, structural or thermodynamic properties can be quite accurately represented while the prediction of dynamic properties remains difficult, especially for multi-component systems. In this work, we use constraint molecular dynamics simulations for calculating dissipative pair forces which are used together with conditional reversible work (CRW) conservative forces in dissipative particle dynamics (DPD) simulations. The combined CRWDPD approach aims to extend the representability of CRW models to dynamic properties and uses a bottom-up approach. Dissipative pair forces are derived from fluctuations of the direct atomistic forces between mapped groups. The conservative CRW potential is obtained from a similar series of constraint dynamics simulations and represents the reversible work performed to couple the direct atomistic interactions between the mapped atom groups. Neopentane, tetrachloromethane, cyclohexane, and n-hexane have been considered as model systems. These molecular liquids are simulated with atomistic molecular dynamics, coarse-grained molecular dynamics, and DPD. We find that the CRW-DPD models reproduce the liquid structure and diffusive dynamics of the liquid systems in reasonable agreement with the atomistic models when using single-site mapping schemes with beads containing five or six heavy atoms. For a two-site representation of n-hexane (3 carbons per bead), time scale separation can no longer be assumed and the DPD approach consequently fails to reproduce the atomistic dynamics. [ABSTRACT FROM AUTHOR]

The representability and transferability of effective pair potentials used in multiscale simulations of soft matter systems is ill understood. In this paper, we study liquid state systems composed of n-alkanes, the coarse-grained (CG) potential of which may be assumed pairwise additive and has been obtained using the conditional reversible work (CRW) method. The CRW method is a free-energy-based coarse-graining procedure, which, by means of performing the coarse graining at pair level, rigorously provides a pair potential that describes the interaction free energy between two mapped atom groups (beads) embedded in their respective chemical environments. The pairwise nature of the interactions combined with their dependence on the chemically bonded environment makes CRW potentials ideally suited in studies of chemical transferability. We report CRW potentials for hexane using a mapping scheme that merges two heavy atoms in one CG bead. It is shown that the model is chemically and thermodynamically transferable to alkanes of different chain lengths in the liquid phase at temperatures between the melting and the boiling point under atmospheric (1 atm) pressure conditions. It is further shown that CRW-CG potentials may be readily obtained from a single simulation of the liquid state using the free energy perturbation method, thereby providing a fast and versatile molecular coarse graining method for aliphatic molecules. [ABSTRACT FROM AUTHOR]

We continue our investigation of the properties of matter at nonequilibrium steady states using a thermodynamic formalism derived from molecular fluctuations. Based on the generalized Clausius inequality, we extend the definition of ‘‘reversible’’ process to include transformations between steady states and relate reversible work and heat to changes in state functions. The variable which is thermodynamically conjugate to the internal energy, that is, the inverse of the generalized thermodynamic temperature, is an integrating factor for the reversible heat. We discuss the relationship of the generalized temperature to the Kelvin temperature, how the generalized intensive variables can be measured, define generalized heat capacities, and obtain the Gibbs–Duhem relationship satisfied by the intensive variables. These ideas are illustrated for two simple steady state systems, a fluid under homogeneous shear and a two level gas which is pumped by radiation. Finally we analyze under appropriate conditions the electromotive force of a chemical reaction system held at a nonequilibrium state. We predict corrections to the Nernst equation which depend on how far the chemical reactions are removed from equilibrium. [ABSTRACT FROM AUTHOR]

Examines the usefulness of work, mechanical energy expenditure, and efficiency estimation in the movements with the stretch-shortening cycle. Conservation-of-energy equation for the body; Analysis of changes in mechanical energy in cyclic motion; Transportation of energy between the body and environment in forms of work and heat.

The purpose of this investigation was to determine, for a planar, multijoint throwing skill, if the interactions of segment energetics change over the course of practice. Eighteen men threw a weighted ball with their dominant arm at a target while the motion was restrained to a horizontal plane. From video data and body segment inertial estimations, the energy transferred by the net joint force and the mechanical work attributed to the net joint moment were calculated for selected practice trials. Performance scores showed an expected improvement over trial blocks. An energetics analysis indicated that, for the throw, the mechanical work generated by muscle and transferred through muscle (i.e., via the net joint moment) across the elbow joint and the energy transferred by the net joint force across the wrist joint increased early in practice; however, no changes were observed in the relative contributions made by these components. The results indicated that, although performance increased significantly, the movement strategy used by subjects was intact throughout practice. [ABSTRACT FROM AUTHOR]

Work and heat are the two predominant forms of energy in the process industry. Considerable savings can be achieved by synergizing the work and heat requirements of process streams. A generalized framework for integrating heat and work simultaneously is proposed based on a mixed‐integer nonlinear programing model for work‐heat exchange network synthesis. Starting with a set of streams with known flows, temperatures, and pressures, a network of single‐shaft‐turbine‐compressors with motors/generators, valves, heat exchangers, and utility heaters/coolers is synthesized for minimized total annualized cost. In contrast to existing works, (1) streams are not preclassified as hot/cold or high/low pressure, (2) pressure changes are allowed for streams with no net pressure change, (3) liquid‐vapor phase changes are allowed, and (4) phase‐based property correlations are used. Successful application of our approach to C3 splitting yields a nonintuitive configuration. Another application of an offshore natural gas liquefaction process is also studied. © 2018 American Institute of Chemical Engineers AIChE J, 64: 2472–2485, 2018 [ABSTRACT FROM AUTHOR]

To investigate the effects of supramaximal high-intensity interval training (SIT) vs functional high-intensity interval training (FIT) on sports performance, oxidative stress, and acute and chronic flow-mediated dilatation (FMD) were observed. Forty-five young male athletes were randomly allocated to control (CON), SIT, and FIT groups. The SIT program consisted of 10 sets of 30 s of cycle ergometry at 170 % of VO2peak alternating with 30 s rest periods. The FIT program consisted of 10 training postures of 30 s alternating with 30 s rest periods, matching the SIT in energy expenditure and duration of training session. Both SIT and FIT groups underwent training 3 times per week for 10 weeks. Maximal oxygen consumption increased significantly in both SIT and FIT groups relative to pre-test status and the CON group (P<0.05), while the height of counter movement jump increased only in the FIT group. FMD increased significantly with 10 weeks of training in both groups relative to pre-test and the CON group. Only the FIT group had increased FMD at 5 min after training in post-test (P<0.05). Plasma malondialdehyde decreased significantly only in the FIT group (P<0.05). In conclusion, both SIT and FIT programs exerted beneficial effects on health-related physical fitness and FMD. However, the FIT program generated superior results in counter movement jump and acute FMD. [ABSTRACT FROM AUTHOR]

The article discusses the concepts of work and inertia frames with the help of a used car.

The concepts of reversibility and reversible work are subtle and illusive. Students often face difficulties in understanding these concepts. The definitions of reversibility given in textbooks on thermodynamics are generally descriptive and qualitative, subject to interpretation. The reversible work often discussed in the textbooks is actually the work produced in a mechanically reversible process and not the work produced in a completely reversible process. Although the P − V work produced in a mechanically reversible process is a path-dependent quantity, the work produced in a completely reversible process (closed or open system) is not a path-dependent quantity. It is a state function provided that the system interacts with a single thermal energy reservoir. In this article, the precise definitions of reversibility which are unambiguous and quantitative are discussed. The work produced in a reversible process is analyzed and discussed in detail. Both closed and open systems are considered. The material described in this article is suitable for third year chemical engineering students who have completed an introductory engineering thermodynamics course in their second year. [ABSTRACT FROM AUTHOR]

It has recently been reported that “the probability of forming a sufficiently large cavity is higher in water than in the corresponding Lennard-Jones fluid” [Abe and Koga, J. Mol. Liq. 200 (2014) 7]. This finding seems to contrast with the widely recognized fact that the magnitude of the reversible work of cavity creation is larger in water than in common organic liquids. In the present analysis, it is shown that the corresponding Lennard-Jones liquid of Abe and Koga can be described as consisting of particles larger in size than water molecules and, possessing the same number density of water, is characterized by a larger volume packing density that, in turn, leads to a marked decrease in the probability of cavity creation. [ABSTRACT FROM AUTHOR]

An enhanced scheme for the determination of equilibrium crystal shapes is introduced. The emphasis of the present study is put on the proper detection of the facets appearing on the crystal surface. The original formulation presented in [1] employs the principle of the virtual work, and the enhanced scheme additionally makes use of a penalty formulation approach. The derivation of the penalty terms is discussed in detail. Finally, the corresponding discrete method is applied to a certain problematic example case presented in [1] resulting now in the correct crystal shape. [ABSTRACT FROM AUTHOR]

The reactions of tricyanometallate precursors, (Ph3PMe)[(Tp4-Me)Fe(CN)3·0.5CH3CN] (1) (Tp4-Me = tri(4-methyl-pyrazol-1-yl)borate) and (NBu4)[(MeTp)Fe(CN)3] (MeTp = methyltris(pyrazolyl)borate) with the presence of the tetradentate tpa ligand (tpa = tris(2-pyridylmethyl)amine) and Fe(ClO4)2·6H2O afford two new cyano-bridged mixed-valence {FeIII2FeII2} molecular squares: [(Tp4-Me)FeIII(CN)3]2[FeII(tpa)]2·2ClO4·H2O (2·H2O) and [(MeTp)FeIII(CN)3]2[FeII(tpa)]2·2ClO4·CH3OH (3·CH3OH). Solvent-exchange compounds of 3·CH3OH, [(MeTp)FeIII(CN)3]2[FeII(tpa)]2·2ClO4·2H2O (3·2H2O), and their solvent-free form (2 and 3) are also obtained, respectively. The spin crossover (SCO) properties of all compounds are confirmed by detailed structural analyses of the coordination environments of the FeII centres and magnetic susceptibility measurements. All compounds exhibit SCO behaviour near room temperature (T1/2 = 320 K for 2·H2O; 302 K for 2; 292 K for 3·CH3OH; 306 K for 3·2H2O and 290 K for 3) and reversible single-crystal to single-crystal (SC–SC) transformations induced by guest desorption and resorption or solvent exchange. The transition temperature close to room temperature can be tuned by the dehydration and re-hydration processes. The structure–property analysis discloses that the distorted {Fe4(μ-CN)4} core and deviations of bent 〈Fe−N≡C angles play a key role in tuning the transition temperature of these similar mixed-valence {FeIII2FeII2} complexes. [ABSTRACT FROM AUTHOR]

The omnipotent Li–ion battery charger with multimode control and polarity reversible techniques is presented in this article. The proposed chip is fabricated with TSMC 0.35μm 2P4M complementary metal-oxide- semiconductor processes, and the chip area including pads is 1.5 × 1.5 mm2. The structure of the omnipotent charger combines three charging modes and polarity reversible techniques, which adapt to any Li–ion batteries. The three reversible Li–ion battery charging modes, including trickle-current charging, large-current charging and constant-voltage charging, can charge in matching polarities or opposite polarities. The proposed circuit has a maximum charging current of 300 mA and the input voltage of the proposed circuit is set to 4.5 V. The maximum efficiency of the proposed charger is about 91% and its average efficiency is 74.8%. The omnipotent charger can precisely provide the charging current to the battery. [ABSTRACT FROM PUBLISHER]

In the study, a two-dimensional closed shell containing fully incompressible fluid is modeled to investigate the behavior of an equatorially anchored deepwater shell storage container. The volume constraint conditions of the shell and contained fluid due to the several external loadings are taken into consideration. The shell, which is installed in deepwater by using anchors at its equator, is assumed to be interacting with the rigid foundation. Since the shell is subjected to periodic anchored forces, the deformed configuration is dependent on the tangential, normal, and circumferential displacements. Therefore, two-dimensional elements are used for investigating the displacements in the shell. Differential geometry is introduced to compute the shell geometry, and small displacement theory is used to calculate the initial strain. The energy functional of the shell and internal fluid are derived from the principle of virtual work in terms of displacements, and are expressed in the appropriate forms. The static deformed configuration of the shell can be obtained by using the nonlinear finite-element method, in which the numerical solutions are solved using an iterative procedure. The validity of the present model and the influence of various geometrical parameters under several external loadings on the shell equilibrium configuration are demonstrated. The results show that the tangential and normal displacements are significant and have an important role in the analysis of a deepwater periodic symmetric shell storage container. [ABSTRACT FROM AUTHOR]

We present the foundations of thermodynamics in a novel sequence in which all basic concepts are defined in terms of well known mechanical ideas. Many definitions are new. The order of introduction of concepts is: system (constituents and parameters): properties: state; energy (without heat and work) and energy balance; classification of states in terms of time evolution; existence of stable equilibrium states; available energy; entropy (without heat and temperature) of any state (equilibrium or not) and entropy balance; properties of stable equilibrium states; temperature in terms of energy and entropy; chemical potentials; pressure; work; heat; applications of balances. This novel sequence not only generalizes the subject of thermodynamics to all systems (large or small) and all states (equilibrium and not equilibrium) but also avoids both the conceptual and definitional difficulties that have been recognized by so many teachers, and the confusion experienced by so many students. [ABSTRACT FROM AUTHOR]

A conference paper about the use of thermodynamics in explaining useful work or entropy and its application to fuel needs and fuel utilization. Topics discussed include the laws of thermodynamics based on the work produced from hydraulic engines, the relationship between useful work and fuel usage and the difference of available useful work from Gibbs free energy and enthalpy. A mathematical computation of the available useful work from oxidation of methylene (CH2) is described.

The analyses of thermal systems are necessary because of the energy situation. In this paper, two kinds of thermal systems with work, a common heat–work conversion system and a common heat pump system, are analyzed with the entransy theory. The entransy terms and variations for thermal system with heat–work interaction are discussed. The concept of entransy variation associated with work is proposed. The results show that the entransy variation associated with work is directly related to output work and has the same change tendency as that of the work. [ABSTRACT FROM AUTHOR]

In this brief, the implementation of residue number system reverse converters based on well-known regular and modular parallel-prefix adders is analyzed. The VLSI implementation results show a significant delay reduction and area \times^2 improvements, all this at the cost of higher power consumption, which is the main reason preventing the use of parallel-prefix adders to achieve high-speed reverse converters in nowadays systems. Hence, to solve the high power consumption problem, novel specific hybrid parallel-prefix-based adder components that provide better tradeoff between delay and power consumption are herein presented to design reverse converters. A methodology is also described to design reverse converters based on different kinds of prefix adders. This methodology helps the designer to adjust the performance of the reverse converter based on the target application and existing constraints. [ABSTRACT FROM PUBLISHER]

Incoming and outgoing solar radiation couple with heat exchange at Earth's surface to drive weather patterns that redistribute heat and moisture around the globe, creating an atmospheric heat engine. Here, we investigate the engine's work output using thermodynamic diagrams computed from reanalyzed observations and from a climate model simulation with anthropogenic forcing. We show that the work output is always less than that of an equivalent Carnot cycle and that it is constrained by the power necessary to maintain the hydrological cycle. In the climate simulation, the hydrological cycle increases more rapidly than the equivalent Carnot cycle. We conclude that the intensification of the hydrological cycle in warmer climates might limit the heat engine's ability to generate work. [ABSTRACT FROM AUTHOR]

Acrylic bone cement has been an essential non-metallic implant used as fixing agent in the cemented total joint arthroplasty (THA). However, the currently available materials based mainly on polymethylmethacrylate (PMMA) still encounter certain limitations, such as time-consuming polymerization, thermal and chemical necrosis and troublesome revision procedure. Here from an alternative way, we proposed for the first time to adopt the injectable alloy cement to address such tough issues through introducing its unique liquid–solid phase transition mechanism. A typical cement along this way is thus made of an alloy Bi/In/Sn/Zn with a specifically designed low melting point 57.5 °C, which enables its rapid molding into various desired shapes with high plasticity and ultimate metallic behaviors. The fundamental characteristics including the mechanical strength, biocompatibility and phase transition-induced thermal effects have been clarified to demonstrate the importance of such alloy as unconventional cement with favorable merits. In addition, we also disclosed its advantage as an excellent contrast agent for radiation imaging on the bone interior structure which is highly beneficial for guiding the surgery and monitoring the therapeutic effects. Particularly, the proposed alloy cement with reversible phase transition feature significantly simplifies the revision of the cement and prosthesis. This study opens the way for employing the injectable alloy materials as reversible bone cement to fulfill diverse clinical needs in the coming time. [ABSTRACT FROM AUTHOR]

This paper is the first part of a three-part project 'How the principle of energy conservation evolved between 1842 and 1870: the view of a participant'. This paper aims at showing how the new ideas of Mayer and Joule were received, what constituted the new theory in the period under study, and how it was supported experimentally. A connection was found between the new theory and thermodynamics which benefited both of them. Some considerations are offered about the desirability of taking a historical approach to teaching energy and its conservation. [ABSTRACT FROM AUTHOR]

Usually, in physics textbooks, the physical magnitude 'work' is introduced as the product of a force multiplied by its displacement, in relation to the transfer of energy. In other words, 'work' is presented as an internal affair of physics theory, while its relation to the world of experience, that is its empirical meaning, is missing. On the other hand, in the history of its creation, 'work' was a concept that had empirical meaning from the start. It was constructed by engineers to measure the work (labor) of motor engines, men, and animals. Very soon however this initial meaning seems to vanish. In this article, it will be looked at how 'work' is presented in physics textbooks, what was its initial meaning in the history of its formulation, under what circumstances this initial meaning faded, and how elements from the history of its creation can be used in the classroom to teach it. [ABSTRACT FROM AUTHOR]

To maintain steady level walking, collision loss is predominantly compensated for with push-off propulsion, and negligible additional work is performed during the single support phase. The observed energy balance during the double support phase is energetically optimal. However, unlike level walking, significant work proportional to the incline slope was observed during the single support phase, which raises the question of whether energetic optimality applies to incline walking. In this study, we examined the energetic optimality of incline walking using a simple work-energy relationship. Work performed by the leading and trailing leg over a gait cycle was estimated for various incline slopes, and the optimal push-off impulse that minimized the total work performed was calculated. The model prediction for least costly gait occurred when push-off propulsion provided all of the necessary work for raising or lowering the body center of mass (CoM) and collision compensation. When we assumed that the generation of optimal propulsion is gradually scaled to obey a feasible push-off constraint, which was estimated based on the allowable plantar flexor torque and the weight support of the trailing leg, the predicted slope-proportional increase in mechanical work done by the ground reaction force (GRF) during the single support phase was consistent with the empirical data. This result implies that the energetic optimality of incline walking can be described from a mechanical perspective and is subject to a feasible push-off propulsion constraint. However, the implication of the mechanical perspective of energetic optimality on the metabolic cost should be further examined and compared using empirical data. [ABSTRACT FROM AUTHOR]

Emergy attempts to measure the environmental work required to generate (ecosystem) goods and services that can be used by humans. It is claimed that the use of inventory modelling principles behind the Life Cycle Assessment (LCA) method (European Commission, 2010a) may improve the Emergy Synthesis method, which has been criticized for its low accuracy and lack of standardization in the accounting procedure. LCA has become a standard procedure to investigate the environmental performance of human-dominated products and processes. Where LCA fundamentally differs from Emergy Synthesis is in that the former draws the boundary around the life cycle of the system under study, and looks at impacts that happen as direct consequences of it; conversely, Emergy Synthesis always looks at a system as embedded in the larger natural system that underpins it, and includes all direct and indirect inputs that converged to support it over much larger time and space scales, including ‘freely available’ ones which are typically neglected or only partly accounted for in LCA (e.g. rainfall, soil organic matter, etc.). Emergy arguably offers the added value of a comprehensive donor-side perspective, an approximation of the work of the environment that would be needed to replace what is used, and presents a unified measure of the provision of environmental support. We maintain that it may be viewed as a valuable complement, rather than an alternative, to existing life cycle impact assessment metrics. The lingering obstacles to such integration are enumerated and discussed. [Copyright &y& Elsevier]

The Hong-Ou-Mandel (HOM) experiment was a benchmark in quantum optics, evidencing the non- classical nature of photon pairs, later generalized to quantum systems with either bosonic or fermionic statistics.Weshow that a simple modification in the well-known and widely usedHOMexperiment provides the direct measurement of the Wigner function. We apply our results to one of the most reliable quantum systems, consisting of biphotons generated by parametric down conversion. A consequence of our results is that a negative value of the Wigner function is a sufficient condition for non-gaussian entanglement between two photons. In the general case, the Wigner function provides all the required information to infer entanglement using well known necessary and sufficient criteria. The present work offers a new vision of the HOM experiment that further develops its possibilities to realize fundamental tests of quantum mechanics using simple optical set-ups. [ABSTRACT FROM AUTHOR]

We consider reversible work extraction from identical quantum systems. From an ensemble of individually passive states, work can be produced only via global unitary (and thus entangling) operations. However, we show here that there always exists a method to extract all possible work without creating any entanglement, at the price of generically requiring more operations (i.e., additional time). We then study faster methods to extract work and provide a quantitative relation between the amount of generated multipartite entanglement and extractable work. Our results suggest a general relation between entanglement generation and the power of work extraction. [ABSTRACT FROM AUTHOR]

Abstract: Coordinative chain transfer polymerization (CCTP) of 1,3-butadiene was assessed by employing several traditional Ziegler–Natta type Nd-based catalytic systems. Both the types of alkylaluminum as CTA and chloride donor as third component significantly affected the chain transfer characteristic of the CCTP systems. Among the catalytic systems examined, Nd(OiPr)3/Al(iBu)2H/Me2SiCl2 and Nd(OiPr)3/Al(iBu)2H/Al2Et3Cl3 systems exhibited the highest catalytic efficiency, yielding 6–10 polymer chains per Nd atom in the presence of 20 equiv. CTA. Kinetic examination revealed that Nd(OiPr)3/Al(iBu)2H/Me2SiCl2 and Nd(OiPr)3/Al(iBu)2H/Al2Et3Cl3 catalytic systems proceeded with fully- and semi-reversible chain transfer reactions, respectively. Quantitative formation of polymers was observed in each step of the 1,3-butadiene seeding polymerization, indicating the living mode of the two catalytic systems. Moreover, the triblock copolymers, PBD-b-PIP-b-PBD and PBD-b-PIP-b-PCL, were successfully synthesized with Nd(OiPr)3/Al(iBu)2H/Me2SiCl2 catalytic system. [Copyright &y& Elsevier]

Fast, reversible redox reactions in solids at low temperatures without thermomechanical degradation are a promising strategy for enhancing the overall performance and lifetime of many energy materials and devices. However, the robust nature of the cation's oxidation state and the high thermodynamic barrier have hindered the realization of fast catalysis and bulk diffusion at low temperatures. Here, we report a significant lowering of the redox temperature by epitaxial stabilization of strontium cobaltites (SrCoOx) grown directly as one of two distinct crystalline phases, either the perovskite SrCoO3−δ or the brownmillerite SrCoO2.5. Importantly, these two phases can be reversibly switched at a remarkably reduced temperature (200-300 °C) in a considerably short time (< 1 min) without destroying the parent framework. The fast, low-temperature redox activity in SrCoO3−δ is attributed to a small Gibbs free-energy difference between two topotatic phases. Our findings thus provide useful information for developing highly sensitive electrochemical sensors and low-temperature cathode materials. [ABSTRACT FROM AUTHOR]

This article reviews the existing work in self-healing and self-repairing technologies, including work in software engineering, materials, mechanics, electronics, MEMS, self-reconfigurable robotics, and others. It suggests a terminology and taxonomy for self-healing and self-repair, and discusses the various related types of other self-* properties. The mechanisms and methods leading to self-healing are reviewed, and common elements across disciplines are identified. [ABSTRACT FROM AUTHOR]

It is intriguing how the mechanics of molecular motors is regulated to perform the mechan-ical work in living systems. In sharp contrast to the conventional wisdom, recent experi-ments indicated that motor force maintains ~6 pN upon a wide range of filament loads during skeletal muscle contraction at the steady state. Here we find that this rather precise regulation which takes place in an essentially chaotic system, can be due to that a "working" motor is arrested in a transitional state when the motor force is ~6 pN. Our analysis suggests that the motor force can be self-regulated through chemomechanical cou-pling, and motor force homeostasis is a built-in feature at the level of a single motor, which provides insights to understanding the coordinated function of multiple molecular motors existing in various physiological processes. With a coupled stochastic-elastic numerical framework, the kinetic model for a Actin-myosin-ATP cycle constructed in this work might pave the way to decently investigate the transient behaviors of the skeletal muscle or other actomyosin complex structures. [ABSTRACT FROM AUTHOR]

Abstract: This paper demonstrates the reversible fault tolerant logic synthesis for the Field Programmable Gate Array (FPGA) and its realization using MOS transistors. Algorithms to design a compact reversible fault tolerant n-to- decoder, 4n-to-n multiplexers, a random access memory and a Plessey logic block of the FPGA have been presented. In addition, several lower bounds on the numbers of garbage outputs, constant inputs and quantum cost of the FPGA have been proposed. The comparative results show that the proposed design is much better in terms of gate count, garbage outputs, quantum cost, delay, and hardware complexity than the existing approaches. [Copyright &y& Elsevier]

Multi-flute curved edge drills have constructions characterized by the geometry of the main edge having a variable clearance angle, decreasing from top to periphery. As a result, the performances of this construction are different from those of a standard drills as far as wear behaviour is concerned regarding axial force and the torque of cutting generated in the process, as a result of increasing the active length of the main edge of the drill. The paper presents experimental research of curved edge drills, performed comparatively with standard drills, as far as wear size over time is concerned and research regarding geometric roughness of generated surface, in an identical work environment, when processing A570 type steel. The experimental research of the size of axial force and of torque, generated in the process of drilling, allowed us to determine the constants and the exponents in the relationships of axial force calculations and torque for cutting when processing alloys, with straight edge drills, as well as curved edge drills. [ABSTRACT FROM AUTHOR]

The paper presents the design and operating characteristics of a model of reversible axial fan with only one impeller, whose reversibility is achieved by changing the direction of rotation. The fan is designed for the purpose of providing alternating air circulation in wood dryers in order to reduce the consumption of electricity for the fan and increase energy efficiency of the entire dryer. To satisfy the reversibility of flow, the shape of the blade profile is symmetrical along the longitudinal and transversal axes of the profile. The fan is designed with equal specific work of all elementary stages, using the method of lift forces. The impeller blades have straight mean line profiles. The shape of the blade profile was adopted after the numerical simulations were carried out and high efficiency was achieved. Based on the calculation and conducted numerical simulations, a physical model of the fan was created and tested on a standard test rig, with air loading at the suction side of the fan. The operating characteristics are shown for different blade angles. The obtained maximum efficiency was around 0.65, which represents a rather high value for axial fans with straight profile blades. [ABSTRACT FROM AUTHOR]

Low-pressure axial fan impellers designed according to the principle of equal specific work of all elementary stages have blades whose profile near the fan hub is under a significantly larger inclination angle than at the impeller periphery. In order to minimize the spatial curvature of the fan blades and the fan hub length, impeller blades of low-pressure axial fans can be designed with different specific work of elementary stages, so that the specific work of elementary stages is smaller at the hub than at the periphery. This paper presents the operating characteristics of a low-pressure reversible axial fan with straight blade profiles, designed with different specific work of elementary stages. The fan was tested on a standard test rig, with air intake loading on the suction side of the fan. [ABSTRACT FROM AUTHOR]

SUMMARY Absorption refrigeration cycles are alternatives to conventional vapor-compression cycles in which the energy required for refrigeration is provided by heat instead of mechanical work. In this paper, a novel refrigeration cycle utilizing the immiscible liquid-phase separation behavior is simulated and analyzed using Aspen simulator. The two conjugate liquids adopted in this work are triethylamine (solute) and water (solvent). This binary system has a low critical solution temperature of 18 °C. The thermophysical properties of the binary mixture are generated using the universal functional activity coefficient (UNIFAC) and the nonrandom two-liquid (NRTL) models. The phase splitting phenomenon at the generator temperature is predicted by both models. However, in comparison with the available experimental data for the same binary mixture, NRTL model gives better predictions for the flow rates and compositions of the material streams. Heat duties of the evaporator, absorber, and generator and the power consumption of the solution pump have been calculated using UNIFAC and NRTL models. The cycle COP that plays a major role in determining the cycle economical viability has been predicted for different operating conditions using the two models. Simulation results show that, for a waste heat reservoir at 60 °C and using NRTL model, the COP is about 2.0. Second law analysis conducted for all cycle components of the cycle shows that about 42% of the total exergy destructed occurs in the generator. Finally, the liquid-phase separation refrigeration cycle is predicted to be a promising cycle in the near future because of hardware and energy savings. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Choosing a system of interest and identifying the interactions of the system with its environment are crucial steps in applying the relation between work and energy. Responses to problems that we administered in introductory calculus-based physics courses show that many students fail to recognize the implications of a particular choice of system. In some cases, students do not believe that particular groupings of objects can even be considered to be a system. Some errors are more prevalent in situations involving gravitational potential energy than elastic potential energy. The difficulties are manifested in both qualitative and quantitative reasoning. [ABSTRACT FROM AUTHOR]

Abstract: Previous studies of the mechanical work performed during uphill and downhill walking have neglected the simultaneous negative and positive work performed by the leading and trailing legs during double support. Our goal was to quantify the mechanical work performed by the individual legs across a range of uphill and downhill grades. We hypothesized that during double support, (1) with steeper uphill grade, the negative work performed by the leading leg would become negligible and the trailing leg would perform progressively greater positive work to raise the center of mass (CoM), and (2) with steeper downhill grade, the leading leg would perform progressively greater negative work to lower the CoM and the positive work performed by the trailing leg would become negligible. 11 healthy young adults (6 M/5 F, 71.0±12.3kg) walked at 1.25m/s on a dual-belt force-measuring treadmill at seven grades (0, ±3, ±6, ±9°). We collected three-dimensional ground reaction forces (GRFs) and used the individual limbs method to calculate the mechanical work performed by each leg. As hypothesized, the trailing leg performed progressively greater positive work with steeper uphill grade, and the leading leg performed progressively greater negative work with steeper downhill grade (p<0.005). To our surprise, unlike level-ground walking, during double support the leading leg performed considerable positive work when walking uphill and the trailing leg performed considerable negative work when walking downhill (p<0.005). To understand how humans walk uphill and downhill, it is important to consider these revealing biomechanical aspects of individual leg function and interaction during double support. [Copyright &y& Elsevier]

When an adaptive agent works with a human user in a collaborative task, in order to enable flexible instructions to be issued by ordinary people, it is believed that a mutual adaptation phenomenon can enable the agent to handle flexible mapping relations between the human user's instructions and the agent's actions. To elucidate the conditions required to induce the mutual adaptation phenomenon, we designed an appropriate experimental environment called 'WAITER' (Waiter Agent Interactive Training Experimental Restaurant) and conducted two experiments in this environment. The experimental results suggest that the proposed conditions can induce the mutual adaptation phenomenon. [ABSTRACT FROM AUTHOR]

This study investigates the effects of late intake valve closing and early exhaust valve opening on volumetric efficiency and lost work in a four-stroke spark ignition engine. The effects of pressure drop through intake and exhaust poppet valves were also studied. Two basic valve lift profiles - namely sinusoidal and instantaneous - were considered in this study. The effects of late intake valve closing and early exhaust valve opening were examined for various engine speeds, valve sizes, and valve discharge coefficients. Finally, an optimum intake valve closing angle to maximize the volumetric efficiency and an optimum exhaust valve opening angle to minimize lost work were established. [ABSTRACT FROM AUTHOR]

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