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This paper investigates the possibility of DC-link capacitor testing in multi-leg converters. Operating conditions similar to ones expected in normal operation can be achieved with the circular power flow, which is possible in multi-leg converters. Two cases are considered. The first one is DC/DC buck converter and second one is dual three-phase drive. Based on simulation results it can be asserted that regenerative/synthetic load can be comparable to normal load with proper setup of operational parameters.

A planetary rover experiences mobility problems, such as excessive slippage and entrapment, on loose terrain known as regolith. To prevent such situations, understanding wheel-soil interaction mechanics is necessary. Thus, this study focuses on the soil deformation beneath a grouser wheel and the wheel traction performance. The soil deformation is analyzed by using particle image velocimetry (PIV) technique, and the wheel traction is measured by a force-torque (FT) sensor. The experimental results present that the soil around a grouser moves to the directions on the front and rear of the wheel when the grouser enters into the soil. After that, the soil flow describes an arc-shaped flow from the front of the wheel towards the rear-end of the wheel caused by the grouser. These results indicate that the grouser wheel causes a different flow of soil than a wheel without grousers. Therefore, a model for the grouser wheel that takes into account the soil deformation must be developed in the future. We also investigate the effects of the normal load of the wheel on the soil deformation. The normal load of the wheel affects the thickness of the soil deformation area rather than the shape of the boundary line of the soil deformation area. In addition, the maximum thickness of the soil deformation area and the velocity of the soil particles increase with an increase of the normal load of the wheel. As for the wheel performance, the increase of the normal load causes an increase of wheel sinkage and traveling traction. From these results, it can be deduced that an increase in the thickness of the soil deformation area leads to an increase in the traction performance of the grouser wheel. In conclusion, this work contributes further to the understanding of wheel-soil interaction and the relationship between wheel performance and soil deformation.

A high level of individuals on the planet is living in decentralized, rustic and remote territories which are topographically detached from lattice association. Power dissemination and consistent fuel transportation to create electrical vitality for these regions represent an awesome test. A savvy lattice mixture vitality framework has been outlined and mimicked to help a little group considering a normal load request of 72 kWh/d and a pinnacle heap of 7 kW. The recreation and enhancement procedure of the cross breed vitality framework, with the thought of meteorological information, have been finished by HOMER Software. Reenactment comes about demonstrate that the proposed framework is financially and ecologically doable, and that the Net Present Cost (NPC) and in addition CO 2 outflow are diminished by around 74% and 92% separately every year contrasted with customary power plants. The NPC of the streamlined framework has been observed to be about US$ 76,901 with the Cost of Energy (COE) of about US$ 0.198/kWh. This upgraded mixture vitality framework will be pertinent for every single other area on the planet with comparative meteorological and natural conditions.

In this work, different cognitive load situations are examined and classified in the context of a Human Computer Interaction (HCI) scenario. Machine learning methods were used to detect three cognitive load states (overload, underload, normal load) with the help of five different psychophysiological signals (ECG, EMG, Respiration, GSR, Temperature). At first it is shown, that the three regarded states can be clearly distinguished in the Valence-Arousal-Dominance space (VAD). After this comparisons between a 10-fold-valdidation and a batch-validation as well as three different classifiers (k-Nearest-Neighbour, Naive Bayes, Random Forest) are accomplished. At last the influence of gender in contrast to an overall analysis is shown.

Flexible sensing resistors are satisfied for general-purpose applications in recording interactive force during hand manipulation. However, FSR sensors are considerably sensitive to shear. In this paper, shear effect of a Tekscan FlexiForce A401 sensor was investigated with a reformed offset runout detection instrument. Sensor output increased caused by shear stress is significant with normal load decreased and shear stress increased. The calibration of FSR output is necessary because shear effect is not sensitive and removed instantly. Considering the linearity of shear stress and normal load, a regression fit demonstrated the relationship between FSR sensors output and combination of normal load and shear stress. With this fit model, the calibrated signal of force measured by FSR Sensor was more accurate for reviving interactive force during hand manipulation.

In order to increase the performance and efficiency of current tactile sensors, the study on the versatility of the human hand and tactile function could provide excellent hint. Our objective is to develop a new algorithm based on comparing the behavior of human tactile mechanism (using psychophysics experiment) vs. a robotic hand (equipped with 3-axis tactile sensor) using stainless steel (SUS) foils and 1,000-yen bills as medium. The significance of tangential load is highlighted to distinguish between material thicknesses. The result from the first experiment shows that using normal vs. angled load, the Weber fraction is high during low thickness and decreased with increase of thickness. In the second experiment, we find that the ability to distinguish between sheet numbers improves by increasing tangential load compared to just normal load. Overall, it is noted that the tangential load makes the tactile sensor distinguish extremely thin material.

This paper proposes an annual probabilistic model for the energy consumed by a fleet of plug-in hybrid electric vehicles (PHEV) based on Monte Carlo simulation (MCS). This model presents the PHEV charging load scenarios and their probabilities for each hour of the year, which can be easily combined with the normal load models. This facilitates the utilization of this model by local distribution companies to quantify the impacts of PHEV charging on their systems and to define the penetration limit of PHEV in each territory.

Pressure distributions on interaction between wheel-rail caused slip and adhesion area at contact patch. The present paper proposes analytical study on pressure distributions which cause wear and temperature rises at contact area. Hertzian contact law was modified to determined pressure distributions. Normal and tangential load was taken into account to predict depth of wear. Laplace one-dimensional continuum equation was used to determined contact temperature. This prediction has been validated using pin-on-disc experimental technique using normal load of 100 N. The results show pressure distributions can be used to predict wear rates and contact temperatures.

To study the influence factors of aluminum alloy Fretting fatigue life, the global finite element model is employed. The effectiveness of the model is validated according to the comparison of analytical solutions and numerical solutions. A new fretting fatigue life prediction model has been proposed base on friction work. The rationality and effectiveness of the model are validated according to the contrast of experiment life and predicting life. At last influence factor on fretting fatigue life of aerial aluminum alloy LY12CZ is investigated with the model. The results reveal that fretting fatigue life decreases monotonously with the increasing of normal load and then becomes constant at higher pressures. At low normal load, fretting fatigue life increases with the incline of pad radius. At high normal load, however, the fretting fatigue life is unrelated with the fretting pad radius. The bulk stress amplitude has the dominant effect on fretting fatigue life. The fretting fatigue life diminishes as the bulk stress amplitude increases.

Since the province of Yunnan carried out weight calculating program, We have achieved preliminary accomplishments on administering overload and over limit transportation, decreasing traffic accident happening, highway property protecting. But, as the result of our province implement this program still very short, there are many problems in practical experience and these problems needs to be resolved immediately. This essay, firstly by comparing on loading based toll collection model of some provinces in China, then to choose and contrast much reasonable weight estimating toll modal, Secondly, by analyzing and considering from this two aspects: normal load and overload transportation vehicles; Thirdly, to utilize the accumulated experience and data on investigation and studying of weight calculating toll, and on this basis of it to make evaluation after administering about this modal, to acquire the disadvantages of this existing model; Finally, to emphasize from differentiating normal load preferential interval, determining on overload extra coefficient, at the same time to integrate area theory, to make optimization for loading based toll collection model of our province. The aim is to consummate this theory of weight estimating toll, to satisfy speedy development, in addition to make the reference judgment of government policy making department.

The release of metal ions and wear debris are raising serious concerns on metal-on-metal (MoM) hip prosthesis. The purpose of this work was to evaluate the corrosion and tribocorrosion behavior, of a low-carbon CoCrMo alloy, as a function of proteins content in the biological fluid and normal applied load. Electrochemical tests were performed to study the corrosion behavior of the alloy, under two simulated body fluids: phosphate buffer solution (PBS) and bovine calf serum (BCS). The tribocorrosion tests were performed using the same solutions, under different loading conditions and tribometer configuration. An attempt was made to evaluate the synergistic interactions between corrosion and wear. The surface characterization of the sample was also studied. The presence of proteins was found to improve the corrosion resistance and passive behavior due to their protective boundary lubricant effect. Normal applied load showed to increase the passive film destruction.

This paper discusses relationships and differences between a tire under braking and driving conditions, and the processes utilized to predict the tire's driving force characteristics. In the current paper, dynamic normal load distribution and dynamic friction are included into the analytical tire model which is validated by comparing simulated results to experimental data. The physical parameters of tire and friction are extracted from experimental data using UniTire. Finally the driving force characteristics are predicted and compared to those obtained from tire test equipment.

Cold load pickup needs to be included as one of the considerations when protective relay set-points are selected for distribution feeder protection. It's universally recognized that, when a feeder is restored after an extended outage, the load can exceed the normal feeder load until normal load cycling is re-established. However, numerous feeder specific variables need to be considered. The methodology described in this report provides a perspective of relationships between load type, load diversity, percent of circuit load for various load types, and cold load pickup. It is noted, however, that the methodology in this report was developed with the assumption that an outage of sufficient duration (to establish cold load pickup) has occurred during peak load conditions.

As multi-core processors evolve, coherence traffic between cores is becoming problematic, both in terms of performance and power. The negative effects of coherence (snoop) traffic can be significantly mitigated through snoop filtering. Shielding each cache with a device that can squash snoop requests for addresses known not to be in cache improves performance significantly for caches that cannot perform normal load and snoop lookups simultaneously. In addition, reducing snoop lookups yields power savings. This paper describes the design of the Blue Gene/P snoop filters, and presents hardware measurements to demonstrate their effectiveness. The Blue Gene/P snoop filters combine stream registers and snoop caches to capture both the locality of snoop addresses and their streaming behavior. Simulations of SPLASH-2 benchmarks illustrate tradeoffs and strengths of these two techniques. Their combination is shown to be most effective, eliminating 94-99% of all snoop requests using very few stream registers and snoop cache lines. This translates into an average performance improvement of almost 20% for the NAS benchmarks running on an actual Blue Gene/P system.

With the extensive use of digital measurement devices for measuring several power system parameters by a common data acquisition system, the need for a wide dynamic range data acquisition system has become critical. The design of such data acquisition system should be done carefully so that small neutral current, normal load current, and high level of fault current can be measured without compromising the accuracy. This paper discusses a methodology by which a proper data acquisition system can be designed with wide dynamic range.

The electrified railway is one of main harmonic sources in utility. Compared with normal load, the most characteristics of traction are random time varying and non-symmetry. So the harmonic of traction load is very different from normal load of utility. So the evaluating method right for normal load may be not suitable for traction load. So finding a proper estimating method for traction load harmonic is main purpose of this paper. A practical method of evaluating harmonic emission level of electrified railway is brought out based on IEC61000-3-6 in this paper, including confirmation of emission limits, distribution method of emission limits of user and detailed evaluating harmonic emission of traction loads. An example is used to illustrate the rationality of proposed idea.

In this paper, the modeling and design for frictional loads applied by robotic fingertips through a soft contact interface are investigated. The dependence of the sustainable friction forces and moments due to the normal force applied on the contact area is studied. A model that considers the dependence of both the contact area and the coefficient of friction on the application of normal force is proposed. Specimens of simplified fingertips, made with different materials and shaped with different thickness of the covering soft layer, were tested in order to validate the proposed model via designed experiments. The results obtained have very important relevance to the design of robotic hands and fingers equipped with soft pads or skins, and can help in the choice of suitable features for the different layers of contact pads or skins.

Theoretically, a conventional 60/spl deg/ phase spread winding can be subdivided into two components, one of which is connected in star and the other in delta. The two components may occupy different electrical spacing. According to the new principle, a 3-phase induction motor is designed with the two winding components being connected in series to 3-phase power supply. Analysis has shown that this new type of machine has a high winding coefficient and low harmonic content. The winding can be arranged in technological short-pitch. The ratio of the number of effective turns and cross-sectional area between star and delta winding components should be theoretically in 1:/spl radic/3 and /spl radic/3:1 respectively, but slight difference is allowed in practice. The analysis of the MMF. harmonics proves that the harmonic content is remarkably reduced in the new winding. The tests of the prototype machines showed that the new type of the motors has an improved performance. Also, the test results showed that there is no overheating behaviour for new winding motors to operate at normal load.

The increase of distributed generation in the network of Nuon results in challenges for both operation and planning. The load profiles are influenced by the varying amount of distributed generation. This makes the detection of maximum load more complicated. During faults in the network the generation shuts down resulting in an increase of transformer load and temporary lower voltages. It is therefore necessary to find out the penetration of distributed generation in the network and to evaluate the normal load from this data. Based on measurements of mixed feeders and reference DG feeders it is possible to split the data of the mixed feeder into normal load and generation

A new regime of friction-superlubricity-where friction completely vanishes has recently been discovered. This paper discusses superlubricity mechanisms, which can be utilized for Micro Electro Mechanical Systems (MEMS), such as microvalves and micro-assembly systems. From studying friction properties such as the dependence of interfacial lattice misfits and of normal load, it is found that superlubricity is stable under high contact pressure conditions. Experimental evidence of superlubricity is presented by examining systems of sliding atomically clean surfaces by using ultra-high vacuum scanning tunneling microscopy. We have, consequently, proposed the methods for controlling friction and for bonding surfaces by using the superlubricity mechanisms.