nils-herrmann/clean_scirepeval huggingface dataset:
Stability analysis of surrounding rock of unlined highway tunnel in Chongqing

Taking the Daxihe unlined tunnel located at Fuling-to-Pengshui section of 319 federal highway partly in Three Gorges Reservoir Region as project background and choosing its typical sections, numerical analysis for the stability of surrounding rock, based on coupled fluid-solid theorem, was done with Fast Lagrangian Analysis of Continua in three-dimension(FLAC3D). Meanwhile, effects of multiple factors such as unsymmetrical pressure, rock mass weathering degree, change of groundwater tables etc on the stability of surrounding rock were studied when considering fluid-solid coupled effect, resulting in obtainment of principal stresses, placements, plastic zones and pore water pressure distribution of the unlined tunnel under a variety of conditions during its open for trial service. The achieved results are expected to be applied successfully to guidance of the unlined tunnel disease treatment. Furthermore, the study results can also provide a theoretical basis for the disease management of similar tunnels containing water-rich strata.
Structure design of two types of sliding-mode controllers for a class of under-actuated mechanical systems

On the basis of sliding-mode control, two sliding-mode controller models based on incremental hierarchical structure and aggregated hierarchical structure for a class of under-actuated systems are presented. The design steps of the two types of sliding-mode controllers and the principle of choosing parameters are given. At the same time, to guarantee the system's stability, two determinant theorems are presented. Then, by theoretical analysis, the two types of sliding-mode controllers are proved to be globally stable in the sense that all signals involved are bounded. The simulation results show the validity of the methods. Therefore an academic foundation for the development of high-dimension under-actuated mechanical systems is provided.
Research on Performance of Coupled Tent Map Lattices System

Coupled Tent Map Lattices system (CML) has made a good combination between confusion and diffusion, which can be well adopted in the design for Hash function and sequential cipher and possesses high value in cryptographic application. Whereas, Coupled Tent Map Lattices system parameters cast a direct influence on cryptographic performance. This paper chooses tent map as the non-linear function of coupled map lattices and conducted a detailed analysis of the influence of system parameter changes on random feature, differential distribution feature, invariant distribution feature, complexity, Lyapunov exponent, balance of the sequence generated by CML, to serve as a reference for cryptographic system design.
Health Diagnosis for Aircraft Based on EMD and Neural Network

To effectively diagnose the aircraft structure components fatigue damages, a new kind of health diagnosis approach for the aircraft, based on experience modal decomposition (EMD) and probabilistic neural network (PNN), is proposed in this paper. The advanced acoustic emission (AE) technique is used to monitor the aircraft stabilizer health state and get the AE information. And the AE information from the aircraft stabilizer is decomposed into the limited inherent modality function (IMF) by the EMD, which is quite fit for dealing with the non-linear and non-steady signal. The IMF energy is extracted to construct the eigenvectors. Then the health status of the aircraft can be diagnosed with the eigenvectors by PNN health monitor. Experiments show that this method can effectively monitor the fatigue crack of the aircraft stabilizer. It presents a new approach to diagnose effectively health state of aircraft structure components.
Effects of an electromagnetic shield and armature teeth on the short-circuit performance of a direct drive superconducting generator for 10 MW wind turbines

To reduce the cost of energy of offshore wind energy conversion, large individual wind turbines of 10 MW or higher power levels are drawing more attention and expected to be desirable. Conventional wind generator systems would be rather large and costly if scaled up to 10 MW. Direct drive superconducting generators have been proposed to reduce the generator size, because the electrical machines with superconducting windings are capable of achieving a higher torque density. However, a superconducting machine is likely to produce an excessive torque during a short circuit because of its small reactance. An electromagnetic (EM) shield between the rotor and the stator as well as iron or non-magnetic composite (NMC) armature teeth affects the sub-transient reactance of a superconducting machine so that they play a role in the short-circuit performance of a superconducting wind generator. This paper presents a 10 MW superconducting generator design and studies the effects of material, thickness and position of an EM shield and the effects of NMC and iron armature teeth on the torque and the field current density during a three-phase short circuit at the generator terminal. One result shows that the short circuit torque is not able to be effectively reduced by varying the EM shield and the armature tooth material. The other result shows that the field current density is likely to exceed its critical value during a short circuit although the EM shield material and the armature tooth material take some effect.
Optimal Filtering for Stochastic Descriptor Systems with Delayed Measurements

This note deals with discrete-time stochastic descriptor systems with both instantaneous and delayed measurements. The condition of the estimability for such system is given. By introducing the reorganized measurement sequence, the optimal Kalman filter and corresponding filtering error covariance matrix are derived. The optimal filter is calculated without resorting to state augmentation which lessons the computation demand greatly. A numerical example is presented to illustrate the given algorithm
Dynamic Persistence of Ultrasound Images After Local Tissue Motion Tracking

This paper presents a dynamic filtering algorithm for ultrasound image persistence after motion tracking. We have proved the signal-to-noise-ratio after the persistence processing will be increased by analyzing the variance of the persistence function. To avoid the structure blurring due to internal motion from conventional ultrasound persistence techniques, we apply the sum-absolute-difference (SAD) method to track the internal tissue motion between successive frames. Then, we present a dynamic way to determine the coefficients of the persistence function for effectively reducing speckle noise and also preserving tissue structure. Testing results from in vivo images verify our algorithm by showing better contrast in speckle reduced regions and also clear tissue structure.
Application of an Improved BP Neural Network in Business Forecasting

AI (artificial intelligence) techniques, especially neural network, have been used widely for business forecasting. There are so many factors affecting the business forecasting that the input nodes number is large. Conventional neural network methods suffer from limitations, which make them less than adequate for decision making in dynamic business environment. In order to reduce the input nodes, the factors that affect the business forecasting are standardized firstly. Then they are reduced using the principle components analysis method. For hidden nodes, their number is firstly limited to less than the square root of product of input nodes number and output nodes number. Then the correlation coefficients between different hidden nodes in same layer are calculated. Lastly the hidden nodes are merged or deleted according to correlation coefficients. The structure of improved BP neural network (IBNN) is optimized by above method. The result of the business forecasting using the IBNN is shown to be satisfying
Semi-Supervised Learning Based Color Iris Recognition

In this paper, we first studied some fusion strategies for color images based iris recognition. The strategies include Min, Max, Sum, Product and Weighted Sum. The fusion takes place at the matching scores level of red, green and blue channels. The experiments were carried out on UBIRIS v1.0. No fusion strategy can guarantee an improvement compared to the red channel, which yields the best single channel performance. We present a semi-supervised learning algorithm for iris recognition. Two methods are employed to estimate the distance between a test image and a subject. Every test image is appended to a class as a new template according to the classification result. The experiments show that, in some scenarios leading to acquisition condition change, the semi-supervised learning method can improve the performance.
Grid resource allocation based on particle swarm optimization

Resource allocation in grid environment is a complex undertaking due to the heterogeneity and dynamic nature aroused by wide area sharing. Most of the existing studies for this problem have been found to be performance deficiency or slow convergence. To address the heterogeneous and computationally intractable problem of resource allocation optimization in grid, this paper presents an allocation algorithm for parallel tasks based on particle swarm optimization. The heterogeneity of grid user is tackled by introducing a universal utility function. And that computational intractability is solved using iterative searching of particle swarm. Experimental results show that the proposed algorithm is convergent and performs better than genetic algorithm.
A new embedded helix-type inductor using LTCC technology for high frequency applications

A chip inductor based on the CoTi-substituted hexa ferrite BaFe12O19 was designed by LTCC technology to realize the 0805 size of standard packaging and high frequency applications. Testing results show that the value of inductor is 2.45 μH and cut-off frequency is 508 MHz. And the measured results agree with the simulated data basically, which indicates that the samples can satisfy the need of high frequency inductors. The influences of each factor on the performances of inductor were also analyzed. It is an effective method to resolve the consistency problems between simulation and manufacture.
Numerical simulation of flow in concentric cylinders with the slit wall

Based on CFD, the Taylor-Couette flow in the plain and different slit wall models was studied. The CFD result of the plain model is consistent with the PIV experimental result, which proves that the numerical method is reliable and accurate. For the flow in annulus, the characteristics of Taylor vortex in different models were quantitatively analyzed. This study is focused on the influence of the slit wall on the flow field and comparing the variation of vibration frequency and amplitude. Because of the existence of slit, the axial vibration frequency of the wave vortex is reduced, an well as the vibration frequency of the wavy vortex decreases and along with the increase of the number of the slit when the Reynolds number is 200, the axial vibration amplitude increases.
A distributed service restoration method in active distribution network based on the contraction of frontiers

A distributed service restoration method in active distribution network with distributed generators(DG) interconnected is proposed in this paper. According to local topology, switches are divided intogroups to share local measurements. The restoration process is accomplished by the contraction of frontiers. The frontiers are the decision makers of network reconfiguration based on local communication and they will contract step by step until they meet together in a group. During contraction, the load transfer path and islanding separation will be determined. A simulation case of 10kV distribution network with DGs is studied and the whole process of service restoration is analyzed based on DIgSILENT software.
Protection Scheme for Modular Multilevel Converters Under Diode Open-Circuit Faults

The modular multilevel converter (MMC) is attractive for medium- or high-power applications because of the advantages of its high modularity, availability, and high power quality. Reliability is one of the most important challenges for the MMC consisting of a large number of power electronic devices. The diode open-circuit fault in the submodule (SM) is an important issue for the MMC, which would affect the performance of the MMC and disrupt the operation of the MMC. This paper analyzes the impact of diode open-circuit failures in the SMs on the performance of the MMC and proposes a protection scheme for the MMC under diode open-circuit faults. The proposed protection scheme not only can effectively eliminate the possible caused high voltage due to the diode open-circuit fault but also can quickly detect the faulty SMs, which effectively avoids the destruction and protects the MMC. The proposed protection scheme is verified with a downscale MMC prototype in the laboratory. The results confirm the effectiveness of the proposed protection scheme for the MMC under diode open-circuit faults.
Simulation and modelling of 6-degree of freedom STEP SD 700 industrial robot follow-up on a given trajectory

This paper presents modelling and simulation of 6-degree of freedom (DOF) articulated robot by follow-up, on a given curve trajectory. The robot kinematical model is implemented on STEP SD 700 industrial robot, manufactured by Shanghai STEP Robotics Co., Ltd China. In this research, are going to make a Matlab based application. That will aid user to pick an object (weighing under its carrying capacity) from position “A” and place at position “B” (within robot working range). The user could able to design its work path / trajectory to safe 3M (Man, Machine and Material) by avoiding obstacles and collisions in the congested industrial environments. A fully functional mathematical modelling is constructed and implemented in Matlab R2015a, while robot mechanical structure modeling is developed in PTC Parametric Creo 3.0 software.
Dynamic sliding model control for direct torque control of PMSM based on expected space vector modulation

Firstly, to minimize the ripples of the electric magnetic torque and flux linkage produced in the conventional direct torque control (DTC) system for permanent magnet synchronous motors (PMSM); this paper proposes a expected space vector modulation (ESVM) strategy of DTC. The expected voltage was produced by SVM. PI controller was used in flux and torque controller, instead of hysteresis comparator and switching table in conventional direct torque control. Secondly, to chattering reduction and advance state-dynamic performance of PMSM servo system, a dynamic sliding mode controller was designed. By constructing new switching function with integral term, the first order or high order derivative of control output were introduced in switching function. Dynamic sliding mode control laws with time continuum essentially was obtained. The experimental results show that the steady state and dynamic performance of the proposed DTC based on DSMC are improved dramatically, compared with system of the basic DTC or general SMC.
Implementation of web services for IEC61968 message conformance test

Non-standardization of messages when using IEC61968 messages to fulfill information integration of DMS often causes interoperation failures and affects related works. Effective rules and methods to test IEC61968 messages are deficient now. To solve this problem, layered rules along with a metadata & rule-driven framework of IEC61968 message conformance test are proposed. An extensible & loosely-coupled web services architecture for conformance test is designed and implemented based on the framework, too. The validity of the software is proved by a use case.
Design of a low phase noise LO module for IEEE 802.11ac system

The design of a low-phase-noise local oscillator (LO) module for RF transceivers which support the very high throughput mode of IEEE 802.11ac standard is presented in this paper. This LO module provides both intermediate frequency (IF) LO and radio frequency (RF) LO by using HMC83x series chips. Low pass filters and amplifiers are used to improve output power and suppress harmonics of LO signals. Experimental results show that the designed LO module can generate IF LO signal at 1.05GHz and RF LO signal at a range from 4GHz to 5GHz with 20MHz step. The measured in-band phase noise is -116.14dBc/Hz for 1.05GHz carriers and out-of-band phase noise is -142.51dBc/Hz at 1MHz offset. As to RF LO, the measured in-band phase noise is below 107.48dBc/Hz at 10 KHz offset and out-of-band phase noise is below -132dBc/Hz in a range from 4GHz to 5GHz.
The auto shape recognize method of well logging curve

In order to research the well logging sedimentary and sequence stratigraphy, shape of well logging curve should be recognized first. The first and second rank derivative should be computed at beginning of all part, if the sign of the second rank derivative has changed, the correspondence depth point represent the inflexion of Geophysical logging curve, it's also the interface of stratum, after that, according to the change trend of correspondence logging data within inflexion to define the curve shape, that is, if data is decreased, then the shape be called bell, if data is increased, then the shape be called funnel, if data changed in small range, it be recognize as cylinder, then the well logging curve shape be recognized automatically. According to the method talked above, the data process and shape auto-judgment from well logging curve of a coring well is done. Case result indicated that curve shape can be better recognized through computation of the second rank derivative, identify of inflexion and analysis of the change trend of correspondence logging data within inflexion.
Moving horizon estimation for multi-rate systems

This paper investigates the moving horizon estimation (MHE) problem for process systems with multi-rate sampling and bounded noises, where the sampling rates of the sensors are not identical. In the sense of the multi-rate systems, some sensors may have no measurements at certain sampling times, which can be regarded as measurement missing and may significantly degrade the estimation performance. The main purpose of this paper is to design an estimator by using a multi-rate MHE (MMHE) strategy. A binary switching sequence is introduced to model the multi-rate sampling, and the missing sample of the slow measurement is compensated by a prediction value. By choosing a cost function, the optimal estimator is obtained by solving a regularized least-squares problem. The stability analysis for the optimal estimator is also presented. Finally, a continuous stirred tank reactor (CSTR) example is given to demonstrate the effectiveness of the proposed method.
Caching Policy Toward Maximal Success Probability and Area Spectral Efficiency of Cache-Enabled HetNets

In this paper, we investigate the optimal caching policy, respectively, maximizing the success probability and area spectral efficiency (ASE) in a cache-enabled heterogeneous network (HetNet), where a tier of multi-antenna macro base stations (MBSs) is overlaid with a tier of helpers with caches. Under the probabilistic caching framework, we resort to stochastic geometry theory to derive the success probability and ASE. After finding the optimal caching policies, we analyze the impact of critical system parameters and compare the ASE with traditional HetNet where the MBS tier is overlaid by a tier of pico BSs (PBSs) with limited-capacity backhaul. Analytical and numerical results show that the optimal caching probability is less skewed among helpers to maximize the success probability when the ratios of MBS-to-helper density, MBS-to-helper transmit power, user-to-helper density, or the rate requirement are small, but is more skewed to maximize the ASE in general. Compared with traditional HetNet, the helper density is much lower than the PBS density to achieve the same target ASE. The helper density can be reduced by increasing cache size. With given total cache size within an area, there exists an optimal helper node density that maximizes the ASE.
Implementation of a measurement system on field uniformity of transient electromagnetic field

Electromagnetic pulse and transient electromagnetic field have received a large concern. To guarantee the validity of the test results in transient field facilities, field uniformity is addressed and required in many international standards. This paper focuses on the implementation of such a measuring system according to the field uniformity requirements of MIL-STD-461F. Also the specific requirements are highlighted and the field sensor calibration is detailed. The measurement uncertainty budget of the field uniformity measuring system is briefly given.
Synthesis of a unified unit for evaluating an application-specific set of elementary functions

Fast and accurate evaluation of elementary functions (e.g. 1/ x , log, 3√x, and 1/√x) is vital in many computation intensive applications. This paper presents a synthesis system of a unified hardware unit for evaluating a custom subset of elementary functions. Based on some latest algorithms of software library and new design principles that exploit the parallelism of reconfigurable hardware, fast and compact datapath is automatically generated. The proposed system also enables rapid design space exploration by allowing designers to modify the constraints on each function (e.g. precision, delay, area, etc.). For an arbitrary set of logarithm functions and power series, accuracy around 0.6 ulp (unit of last place) is achieved at double precision, which is 0.3 ulp more accurate than Pentium®, and the speed is 30% faster than Itanium®. The result is simulated by 80nm process.
Initial location assignment and dynamic reassignment optimization for urban evacuation guiders

Urban evacuation is of great significance in saving human lives when disasters strike major cities. Comparing with the large population to evacuate, the number of evacuation guiders is much smaller. Since the location of evacuation guiders can greatly influence the evacuation process, it is crucial to identify the most critical locations to assign guiders. The assignment optimization for evacuation guiders usually suffers from partial information, partial control, uncertainty of individual behaviors and ever-changing traffic conditions during an evacuation. We divide this important problem into two parts: initial location assignment optimization and dynamic reassignment optimization. Both of them are considered in this paper and the major contributions are as follows. First, we mathematically model the assignment optimization problem using Markov decision process (MDP) framework. Second, we make a comparison among three methods that can be applied in initial location assignment optimization. Third, a simulation-based policy improvement method is developed to obtain optimal reassignment policies. Forth, some numerical examples are presented to demonstrate the performance of our methods. We hope this work sheds insight on evacuation guider assignment optimization problem in more general situations.
Optimal siting & sizing of battery energy storage system in active distribution network

Battery energy storage system (BESS) plays great roles in peak shaving, improving voltage quality and providing active power adjustment capacity. The efficiency of active distribution network (ADN) to integrate large scale dispersed energy resources (DERs) largely depends on the rational placement of BESS. The paper focuses on the multi-objective optimal model for siting & sizing BESS in ADN, concerning on peak shaving capacity, voltage quality and active power adjustment capacity. Additionally, the paper proposes a weighted minimum module ideal point method to solve the multi-objectives optimal programming. Finally, the study case results demonstrate the efficiency of the aforementioned optimal siting & sizing BESS model with its solving method.