nils-herrmann/clean_scirepeval huggingface dataset:
Dynamic Modeling of a MW Scale Wind Turbine Generator Yaw Gear System with Elastic Impact and Its Simulation

The modeling of the gear system of wind turbine yaw system with impact was investigated. Based on dynamics of flexible multibody system theory, dynamic equations of the gear system were established. According to Newton's collision model, the dynamics model of the gear system with impact is established. Then the gear system was simulated to obtain the history of the impact force and the angular acceleration. The result shows that the vibration regularity of the outer ring can be revealed by the sudden change of angular acceleration. And the result provides a reference of the bearing dynamic simulation runs.
Analysis of Financing Structure of Electric Power Listed Enterprise

This paper is a study on the financing structure of electric power listed company through an empirical analysis method. According to the financial accounting theory, the suitable financing structure can effectively enhance the value of company. Through a detailed study using the data of electric power listed companies from 2004-2006, which belongs to the security markets of Shanghai and Shenzhen, We summarize the characteristics of electric power listed company: debt financing is the main method widely used in electric power listed company, especially long-term debt financing method. This find bases the foundation for further study of the financing effect of listed power companies. Key wordsfinancing structure; electric power listed company; debt financing
Detecting Link Spam Using Temporal Information

How to effectively protect against spam on search ranking results is an important issue for contemporary web search engines. This paper addresses the problem of combating one major type of web spam: 'link spam.' Most of the previous work on anti link spam managed to make use of one snapshot of web data to detect spam, and thus it did not take advantage of the fact that link spam tends to result in drastic changes of links in a short time period. To overcome the shortcoming, this paper proposes using temporal information on links in detection of link spam, as well as other information. Specifically, it defines temporal features such as in-link growth rate (IGR) and in-link death rate (IDR) in a spam classification model (i.e., SVM). Experimental results on web domain graph data show that link spam can be successfully detected with the proposed method.
A physics-based compact model for material- and operation-oriented switching behaviors of CBRAM

A physics-based compact model is developed to capture the essential resistive switching behaviors of conductive-bridge random access memory (CBRAM) under DC and AC operations. Three types of evolution modes of conductive filament correlated with material properties and operation schemes are modeled based on experimental observations. By modeling the temperature and electric-field effects as well as the electrical conduction, the model can well reproduce the DC and AC switching characteristics in different material stacks and operation modes. The calibrated model can be further implemented into SPICE to evaluate and optimize the array performance of CBRAM as a device-circuit-system co-design tool.
A new resonant gate drive circuit with centre-tapped transformer

This paper presents a new resonant gate drive circuit for a pair of low side switches with 50% duty cycle or less, which is suitable for variable frequency resonant converter, push-pull converter and so on. A centre-tapped transformer is utilized to boost switches' gate voltage twice high as Vcc voltage. Charging and discharging the gate input capacitance by a constant current source increases MOSFETs switching transition speed. The theoretical analysis and simulation waveforms are provided. A prototype board working at 1 MHz is built and experimental results are also given
Adaptive current source drivers for efficiency optimization of high frequency synchronous buck converters

In this paper, the concept of the adaptive CSDs is proposed for high frequency synchronous buck converters. The idea of the adaptive CSDs is to achieve optimal design of the switching loss reduction and the drive loss reduction for wide load range. It should be noted that the adaptive concept is suitable for both the continuous and discontinuous CSDs regardless the drive circuit topologies. Through investigating the CSD circuits, one simple method to achieve the adaptive drive current based on the adaptive voltages is proposed. The linear regulator can be used to achieve the function of the adaptive voltages and drive currents in a cost-effective manner. A 12V input, 1.3V output and 1MHz synchronous buck converter was built to verify the advantages of the proposed adaptive CSDs.
A 1-D propagator for introduction of plane wave to layered magnetized plasma in FDTD method

In the application of finite-difference time-domain (FDTD) method to wideband plane wave scattering from layered magnetized plasma, it is a challenge to solve the oblique incident plane wave source in 2-D/3-D simulation space. In this work, an efficient 1-D source propagator is proposed for initiation of incident plane wave on the total-field/scattered-field (TF/SF) boundary in layered magnetized plasma in order to introduce plane wave source in the FDTD simulation space. The 1-D source propagator is developed by using of the phase match theory at the medium interface. The characteristics of wideband plane wave scattering from an n-layer magnetized plasma sheath are calculated and the comparisons with exact solutions are given that clearly exhibit the accuracy of the 1-D source propagator.
Azimuth resolution improvement of spaceborne SAR images with nearly non-overlapped Doppler bandwidth

This paper deals with the azimuth resolution improvement problems via the coherent combination of the SAR images with nearly zero-overlapped Doppler bandwidth, which corresponding to large along-track baseline. Prior to the combination of the images, the phase bias contributions from the atmospheric propagation delays and baseline measurement errors should be calibrated. The interferogram of the azimuth pre-filtered SAR images are adopted in the classical method, whose performance falls down when the overlapped spectra comes to zero. In this paper, the maximum sharpness optimization is adopted to deal this situation. The proposed method has been tested by processing the real data.
Beating frequency tunable dual-wavelength erbium-doped fiber laser with one fiber Bragg grating

A tunable dual-wavelength erbium-doped fiber laser (EDFL) is proposed and demonstrated. By applying axial and lateral strain simultaneously on the fiber Bragg grating (FBG), the absolute wavelength and wavelength spacing of the EDFL can be tuned continuously. The FBG used included not only the FBG fabricated in standard single-mode fiber, but also the FBG in polarization-maintaining fiber. The experiment results are similar.
A contextual approach for effective recovery of inter-process communication patterns from HPC traces

Studies have shown that understanding of interprocess communication patterns is an enabler to effective analysis of high performance computing (HPC) applications. In previous work, we presented an algorithm for recovering communication patterns from traces of HPC systems. The algorithm worked well on small cases but it suffered from low accuracy when applied to large (and most interesting) traces. We believe that this was due to the fact that we viewed the trace as a mere string of operations of inter-process communication. That is, we did not take into account program control flow information. In this paper, we improve the detection accuracy by using function calls to serve as a context to guide the pattern extraction process. When applied to traces generated from two HPC benchmark applications, we demonstrate that this contextual approach improves precision and recall by an average of 56% and 66% respectively over the non-contextual method.
Digital-to-Time Converter with 3.93 ps Resolution Implemented on FPGA Chips

In this paper, a digital-to-time converter (DTC) based on the principle of quantified phase shift resolution (QPSR) is proposed and tested. The QPSR principle is realized by analyzing the phase relationship between two periodic signals, which distinguishes the proposed DTC from conventional DTCs. For performance evaluation, the proposed DTC is implemented on Xilinx Virtex-5 and Virtex-6 field programmable gate array (FPGA) chip, respectively. The obtained resolution of the DTC implemented on Virtex-5 FPGA is 27.1 ps, and the differential nonlinearity (DNL) and integral nonlinearity (INL) are −0.269~+0.247 least significant bit (LSB) and −0.387~+0.171 LSB. Meanwhile, the DTC implemented on Virtex-6 FPGA can achieve a resolution of 3.93 ps, a dynamic range of 43 s, a DNL of −0.327~+0.358 LSB, and an INL of −2.6093~+2.4754 LSB. Experimental results prove that the proposed DTC features high-accuracy, low-cost, and easy implementation.
Placement in Dependable and Secure Peer-to-Peer Data Grids

In this paper, we consider combining replication and data partitioning schemes to assure data availability, confidentiality, and timely accesses for data grid applications. Data objects are partitioned into shares and shares and dispersed. The shares may be replicated to achieve better performance and availability. We develop models for assessing confidentiality, availability, and communication cost for different placements and use the metrics to guide placement decisions. A new probabilistic security assurance model and an efficient availability computing algorithm have been developed. Due to the nature of contradicting goals, we model the placement decision problem as a multi-objective problem and use a genetic algorithm to determine Pareto optimal placement solutions.
Computational and experimental studies of orthopedic implants heating under MRI RF coils

The heating of orthopedic implants under MRI RF fields were investigated 1.5T and 3T systems. Modeling and experiments were performed on an orthopedic device at different sizes inside an ASTM phantom. It is observed that the induced energy deposition near the device is almost linearly related to the dimension of the orthopedic implants when the device is less than 10 cm in length. Higher temperature rises were found in 1.5T for both computational and experimental studies.
Computational investigation of velocity overshoot effects in double gate MOSFETs

The velocity overshoot effect has been simulated in nano-scale double gate MOSFETs and compared by different simulation method including hydrodynamic model (HD model) and Monte Carlo method (MC method). As we know, the hydrodynamic model tends to overestimate the velocity overshoot, so how much the overestimate of HD model can reach to, and how this overestimate can impair the simulation accuracy of the final device characteristics, is investigated. Based on the simulation results, the quantitative study of the velocity overshoot effect and its related error on the performance of DG MOSFETs are obtained.
AHP based wartime armored equipment chassis failure maintainability probability calculation

On the basis of the peacetime armored equipment chassis failure maintenance workload statistic data, it is gained that the peacetime armored equipment chassis failure maintainability probability function accords with exponential distribution according to the statistics method. With analyzing the maintainability probability parameter influence factors, the wartime and the peacetime mean repair time hiberarchy is founded, applying the AHP with the maintainability probability parameter influence factors as the rule layer, and the combination weights are calculated so that the wartime chassis failure maintainability probability function is got. The relative conclusions are given, and a new method to solve the wartime equipment maintainability orderliness without the wartime statistic data is provided.
A 3D stacked step-down intergrated power module

This paper presents a 3D integrated power module design to effectively save footprint and improve thermal performance. The design reduces the footprint by 40% using a 3D structure in which the inductor is over the top of the regulator. A fixed inductor with a cavity is used to envelop the 3D power module, and the high thermal conductivity of the magnetic core significantly enhances heat dissipation. An efficiency-wise design is applied to the proposed power module and there is a reduction in inductor DC resistance, which can in turn further improve the thermal performance. An analytical thermal model is built to calculate the temperature, 3D FEA (Finite Element Analysis) simulation is also utilized to estimate the improvement in temperature field. A prototype is built to test the electrical and thermal performances as well. The DCR is reduced by more than 30% and the thermal performance is improved by 8–10°C compared with plastic molded power modules.
Dispersion-flattened transmission based on liquid-crystal-coated plasmonic subwavelength structures

Recently, noble metallic annular aperture arrays (AAAs) have drawn considerable attention due to their peculiar properties and great potential for ultracompact optical applications. AAAs have been experimentally confirmed to have much higher peak transmission than simple hole arrays with the same open area. Here, gold AAAs with overlapped apertures are reported. We show that different shapes of nanopillars can be formed by controlling the inner and outer radii, thus affecting the plasmonic properties of the nanostructures including both localized surface plasmon resonances (LSPRs) and surface plasmon polaritons (SPPs). By overlaying a layer of liquid crystals onto these plasmonic nanostructures, a pronounced optical transmission with a broad top-flat passband is observed. This unique property makes such a hybrid device potentially useful for broadband optical filters.
Adaptive Current Source Drivers for Efficiency Optimization of High-Frequency Synchronous Buck Converters

In this paper, the concept of the adaptive current source drivers (CSDs) is proposed for the high-frequency synchronous buck converters. Compared to the previous CSD circuits, the adaptive CSD can achieve adjustable drive current and drive voltage according to different load condition. The benefit is that higher drive current and voltage lead to lower switching loss and conduction loss when the load current increases. Therefore, the adaptive CSD is able to realize optimal design to reduce the switching loss, the gate drive loss, and the conduction loss in a wide load range. It should be noted that the adaptive concept is suitable for both the continuous and discontinuous CSDs regardless the drive circuit topologies. Through investigating the CSD circuits, one simple method to achieve the adaptive drive current based on the adaptive voltage is proposed. A 12 V input, 1.3 V output, and 1-MHz synchronous buck converter with the continuous and discontinuous CSDs was built, respectively, to verify the advantages of the proposed adaptive concept and efficiency improvement.
Anomaly Intrusion Detection Methods for Peer-to-Peer System

Peer-to-peer systems and applications are the hotspot of research of network applications. As peer-to-peer system has no central system and is deployed on an open network, new concerns regarding security have been raised. As an additional security measure, the intrusion detection system would help determine whether unauthorized users are attempting to access, have already accessed, or have compromised the network Intrusion detection, as the second line of defense, is an indispensable tool for highly survivable networks. In this paper two anomaly intrusion detection methods are proposed for peer-to-peer system. The main characters of the methods are that they can detect intrusion in real-time without any expert knowledge and attack signatures. One method uses hidden Markov model to check reflector DoS attacks, another based on adaptive resonance theory, which can learn the normal behavior with unsupervised method. The experimental P2P system is built on FreePastry 1.401 and JDK 1.5.0. The results have indicated that the methods can find DoS attacks immediately and find new intruders with low false alarm rate.
A novel asymmetrical three-level BUCK (ATL BUCK) converter for point-of-load (POL) application

This paper presents a novel, non-isolated step-down converter for the application of point-of-load (POL) voltage regulation. The new converter can achieve higher power density by utilizing a much smaller inductor compared with Buck converter in the POL application. A smaller inductor is achieved by increasing the effective operating frequency applied to the inductor by a factor of 4 and at the same time reducing the voltage applied to the inductor while maintaining the same switching frequency of control switches. The new converter uses two groups of interleaving switches to increase the effective operating frequency on the inductor and a flying capacitor to reduce the voltage across the inductor. The new switch topology is adopted because inductors take up much more space than active switches in a high power density power module [1][2]. A 12V-to-1V/1A prototype demonstrates that the proposed topology can use an inductor that is 77% less inductance than a conventional Buck Converter (i.e. only 23% of Buck's inductance is used in the prototype). Since two groups of switches are interleaved, the RMS (Root Mean Square) current in each group of control switches is reduced to half and the hotspot on the control switches is split into two.
A distributed architecture based on micro-bank modules with self-reconfiguration control regarding battery recovery effect for DC microgrids

This paper proposes a new distributed battery energy architecture based on the micro-bank modules for DC microgrids. The benefits of the proposed architecture include 1) no voltage sharing problem and no overcharge/overdischarge problem; 2) high compatibility and reliability 3) high energy utilization efficiency; 4) reduced volume and weight of the BMS. Taking advantage of the battery recovery effect, a self-reconfiguration discharge strategy is also proposed to further enhance the battery performance and efficiency of the storage system. The simulation results verified the proposed concept and benefits. The preliminary experimental results show that the discharge time of the distributed BESS is increased by 11.6% with the self-reconfiguration control strategy.
A high sensitivity temperature sensor based on a selectively filled photonic crystal fiber sagnac interferometer

A high sensitivity temperature sensor based on a Sagnac interferometer consisting of a segment of selectively liquid-filled photonic crystal fiber (SLF-PCF) is proposed and demonstrated. The SLF-PCF is achieved by the high frequency CO2 laser and possesses unique birefringence feature. Numerical and experimental results are presented, and a high sensitivity temperature sensor with sensitivity of ~-11.6 nm/°C is achieved from 65°C to 85°C.
Adaptive fuzzy tracking control for a class of uncertain nonlinear systems

An adaptive fuzzy control algorithm is designed for a class of uncertain nonlinear nonaffine systems. Fuzzy logic systems are used to approximate unknown nonlinear functions. In contrast to the previous results of nonlinear nonaffine systems, a main advantage is that it does not require a priori knowledge about the sign of the control gain coefficient. It can be proven that the closed-loop system is stable in the sense that all the signals are bounded and the system output track the reference signal to a small neighborhood of the origin by appropriately choosing design parameters.
An IP geolocation method based on rich-connected sub-networks

Recent years have seen a rapid growth of location-aware applications such as targeted marketing, restricted content delivery and location-based security check. Although existing delay-based IP geolocation techniques work well in some developed countries, the assumption of a strong delay-distance correlation that they often rely on may fail in many developing countries for poor network connectivity. To obtain more accurate delay-based IP geolocation results in poor-connected networks, an IP geolocation method based on rich-connected sub-networks is presented in this paper. At first, the network connectivity of one particular network is measured. Next, if the network is poor-connected, the method will divide it and search rich-connected sub-networks based on properties such as ISP and location information of probing hosts and landmarks. Then, based on the discovered rich-connected sub-networks, landmarks and probing hosts are deployed and selected to measure data such as delay, distance and topology, etc. At last, the location of the target host is estimated by modifying the processes of existing delay-based IP geolocation techniques based on selected landmarks and probing hosts. The experiments which cover 30 provinces and 3 major ISPs of China show that the proposed method can find corresponding rich-connected sub-networks and significantly improve the performance of existing typical delay-based IP geolocation techniques in an actual poor-connected network.
An analysis of a hail cloud process and it's hail suppression operation

This paper analyzes the radar echo characteristics of the hail clouds in a strong convection which happens on the daybreak of May 1st, 2011 in Chengdu area. It concludes the comparison and analysis of the top height of the radar echoes, the CAPPI(constant altitude plan position indicating) materials of reflectivity in different altitudes and the RHI(range-height indicating) materials of reflectivity in any direction of the radar station that happen in different time. All the work above is for the early identification and warning of the hail clouds in the hail suppression operation to decrease the effect of the hail disaster. The results show that we can identify the hail clouds 15 minutes in advance. Superimposing the geographic information of the 37mm antiaircraft guns operation points over the radar echoes is useful to hail suppression operation.
COPULA model design and analysis on critical infrastructure interdependency

Critical infrastructure such as power system, transportation system, water supply system, is an important component in a country or a region. If a hazard happens to a certain critical infrastructure, a series of chain reaction will happen. And this will cause other critical infrastructure systems work improperly, and finally will push the country or the region into a disaster. Therefore, it is important to know the interrelationship among the critical infrastructure for risk prevention. The paper presents a system model of interdependence of critical infrastructure based on Copula theory, introduces the collection method and interdependence features of failure factors, describes the calculation process of Copula algorithm model, and analyzes the impact of interdependence features on realization of algorithm. The interdependence of critical infrastructure, including the level of interdependence, the interdependent factor range and the transmit delay time caused by the interdependence can be determined through the analysis of this model. This information can be the theoretical base and effective reference for risk prevention and decision making.
2nd International Workshop on Software Engineering Challenges for the Smart Grid (SE4SG 2013)

The 2nd International Workshop on Software Engineering Challenges for the Smart Grid focuses on understanding and identifying the unique challenges and opportunities for SE to contribute to and enhance the design and development of the smart grid. In smart grids, the geographical scale, requirements on real-time performance and reliability, and diversity of application functionality all combine to produce a unique, highly demanding problem domain for SE to address. The objective of this workshop is to bring together members of the SE community and the power engineering community to understand these requirements and determine the most appropriate SE tools, methods and techniques.