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For tractor operation on deformable terrains, accurate terrain profiles are critically needed to determine the dynamic tractor response, which is affected by the terrain roughness. Effective profiles for tractors operating on agricultural terrains were identified in this study. A novel technique, called independent component analysis (ICA), was used to estimate the effective profiles. ICA can use a known system dynamic response (observed signals) to identify road-induced excitation. In this context, tractor wheel vibration signals were used as observed signals, and the ICA method was used to estimate the source signals, which are the effective profiles of the terrain. The proposed approach was validated by comparing the estimated profiles with those measured by a profiling apparatus in the time and frequency domains. The calculated root mean square error RMSE and the relative error Ef between the measured and estimated profiles showed that the proposed approach can be used to accurately estimate road profiles. A group of grass-field roughness data was taken as an example to compare the characteristics of the original and effective profiles, and the parameters of the effective profiles, such as the RMS, roughness index C and waviness W were found to noticeably change during the interaction between the tractor wheel and the terrain soil.

How to accurately and efficiently measure the profiles of the terrain on which agricultural machines operate has been an ongoing research topic. In this study, a surface profiling apparatus (profiler) was developed to measure agricultural terrain profiles along parallel tracks. The profiler is mainly composed of sensor frames, an RTK-GNSS system (Real Time Kinematics-Global Navigation Satellite Systems), laser sensors, an Inertial Measurement Unit (IMU) sensor and a data acquisition system. Along with a full description of how the terrain profiles were produced, a methodology to compensate for the tractor motion was included in the sensor data analysis. In field profiling validation, two trapezoidal bumps with known dimensions were used to assess the ability of the terrain profiler to reproduce the vertical profiles of the bumps, resulting in root mean square error (RMSE) of 3.6-4.7 mm and 4.5-5.1 mm with profiling speeds of 1.02 and 2.56 km/h, respectively. In addition, a validation test was also conducted on an asphalt road by profiling a flat road with the measuring wheels of the profiler rolling on the flat section but with the tractor wheels driving over a trapezoidal bump to excite the tractor pitch and roll motion. The measured profiles then also exhibited a flat road, which showed the ability of the profiler to remove the tractor motion from the profiling measurements.

For most software systems, pair-wise combinatorial testing is highly practical and effective. This article mainly starts with the specific research status of the pair-wise covering combinatorial test and the main content of the software test, analyzes and compares the existing main implementation algorithms, and then evaluates their specific performance.

This paper proposes a kind of intelligent kitchen management system which integrates various technologies such as sensor, ZigBee, embedded, database, Web application, Android mobile development and so on. The paper introduces the system structure, system function, design plan and system implementation of the system. The system provides many ways to check, manage, control and monitor the kitchen information for users intelligently. It has good practicability and extensibility, and improves the intelligentized level of people's life.

An optoelectronic device current-voltage(I-V) testing platform was established based on the software LabVIEW,including a PCI-GPIB card from American National Instrument(NI) Corporation as well as 6517 Electrometer/High Resistance Meter from Keithley Corporation.Using the LabVIEW program to control Keithley6517,the system has the function of collecting,displaying,storing and analyzing the voltage and current data through the GPIB card.It can also draw the I-V characteristic curve according to the measured data and figure out the relevant parameters of different devices.In this paper,taking solar cell as an example,it figures out the open voltage(Voc),short current(Isc),maximum power(Pm),fill factor(FF) and percentage of conversion efficiency(PCE) of the solar cell.Through contrast test and correction,this system has a maximum error of 0.18%.This system not only has a high degree of automation,but also has a high degree of accuracy and reliability.And it not only can be used in laboratory teaching,also can be used in the factory for solar cell and thin film transistor products performance testing.

Based on the traditional trip attraction model, a new method of operation condition evaluation and supply scale forecasting for public parking facilities is proposed. It begins with the operation condition investigation of existing parking facilities, and then analyzes qualitatively the existing parking facilities supply scale by four indexes. finally, it can calculate the supply scale in predict year. Combined with concrete work of urban parking facilities planning in china, the evaluation index and prediction model were applied, and the parking facilities operation condition, demand, supply scale and internal structure are analyzed deeply. The method proposed in the paper can provide the theory basis for the public parking facilities planning in other cities. DOI: http://dx.doi.org/10.11591/telkomnika.v11i2.2069

Test data generation is a key part in software test area and it is of significance to realize the automation of software testing. The main contribution of this paper lies in that a practical model, which utilizes genetic algorithms as searching policy to generate software structural test data, is proposed. To achieve higher performance, such issues as encoding strategy, algorithms operator evolution, evaluation function construction and instrumentation are addressed in detail, a new method of initialization of population is introduced in order to make the initial population has higher adaptability, and much emphasis is put on algorithms operator evolution, which is a key factor which can highly affect algorithms efficiency, finally, the results show that the application of genetic algorithms in software test data generation is more efficient compared with other methods.

In this paper, a feature perturbation by mutual information is proposed and multiple nearest neighbor classifiers are combined according to this way. Multiple nearest neighbor classifiers system based on feature perturbation can improve the performance of single nearest neighbor classifier biased with the curse of dimensionality. However, there are two problems in multiple nearest neighbor classifiers system based on feature perturbation: (i) how to determine the number of component classifiers, and (ii) how to select features for each component classifier. In this paper, the proposed method by mutual information is able to solve the two problems. (i) The number of component classifiers is set to be the number of classes, and (ii) the selected features for each component classifier are automatically determined by mutual information. In order to evaluate the effectiveness of the proposed method, three UCI datasets are selected. And the proposed method is compared with: (i) NNC, (ii) NNC after feature selection by mutual information, (iii) multiple nearest neighbor classifiers system based on feature perturbation by attribute bagging. The experimental results show that multiple classifiers system is superior to single classifier. And multiple nearest neighbor classifiers system based on feature perturbation by mutual information is better than any other combination methods. In addition, the number of component classifiers in the proposed method is less than any other methods.

Sewage treatment system is a complicated nonlinear system with multi-variables, chemical reaction, biological process and altered loads, hard to describe mathematically. Thus prediction of the effluent quality of sewage treatment plant through a mathematical model has being a challenge. In this paper we adopts regression support vector machine (SVM) to set up a prediction model of a sewage treatment plant with a popular process cyclic activated sludge system (CASS). Kernel function of the prediction model is radial basic function, and parameters of the kernel function are optimally determined by cross-validation. Then the prediction model is used to predict effluent quality of the sewage treatment plant with CASS process. Test result of the case study shows that the prediction model works well and the regression SVM is powerful in predicting effluent quality of CASS process sewage treatment plant with small sample learning ability and good generalization.

Digital product development process involves a good many function interoperations in Internet applications. But the heterogeneity of distributed applications affects their interoperability so as to reduce the accessibility and usability of product data. For the sake of the settle of this matter, an idea of application integration that looks upon service as core and a multi-layer integrated service model on the basis of intelligent service unit (ISU) are proposed to realize dynamic loose application integration. The structure of ISU is designed. The application of Web service technology in integration is also studied with the analysis of integration scenario on PDM/CAD, PDM/CAPP. Intelligent service units running integrated environment based on PDM are designed and realized. The feasibility of the techniques in this paper is validated by the developing of a PDM prototype system.

Objectives This study is designed to investigate the inducing effect of one-arm exercise on inter-arm blood pressure difference (IAD). Methods 50 healthy young subjects were included in the study. 3 min exercises of the right arm elbow flexion and extension were performed. The bilateral brachial blood pressure (BP) was simultaneously measured with two automatic BP measurement devices before (basic) and immediately (0), 5, 10, 15, 20 and 30 min after exercise. The absolute difference in systolic and diastolic BP between the left and right BP equal or over 10 mm Hg was recognised as sIAD and dIAD. Results The baseline data of the SBP and DBP in left and right arms revealed no significant difference (SBP: 110±10 vs 111±11 mm Hg; DBP: 66±8 vs 66±9 mm Hg, both NS). The prevalence of dIAD was 2% at baseline. However this prevalence increased to 80% at 0 min as right arm exercise induced the right DBP decrease and left DBP increase, and then the prevalence decreased gradually within 30 min recover period. The prevalence of sIAD was zero at baseline and the maximal prevalence was 8% during the 20 min post–exercise period. Conclusion One arm exercise can lead to significant inter-arm difference in DBP. Any arm exercise should be avoided before BP measurement.

We report a case of maxillary sinus (MS) aspergillosis studied by positron emission tomography (PET) with F-18 fluorodeoxyglucose (FDG) and by 67Ga-citrate (Ga) single photon emission computed tomography (SPECT). The FDG uptake existed in the lesion and along the inflammatory edematous mucous membrane of the MS. Ga uptake occurred not only in the lesion and in the mucous membrane but also in the MS. Relative quantification, the standardized uptake value (SUV) of the lesion showed relatively high FDG uptake (3.7). But in other reports, many malignant head and neck tumors had a SUV below 3.7. It was thought to be difficult to differentiate between aspergillosis and malignant head and neck tumors by FDG-PET.

Molecular beam epitaxy growth of GaAs-based long-wavelength metamorphic InAs/InGaAs quantum dots (QDs) is investigated. With optimized multi-step-graded InGaAs metamorphic buffer layers and growth conditions, room temperature 1.46 µm emission from InAs/In0.15Ga0.85As QDs is realized, and broad-area laser diodes are fabricated with a very low etch pit defect density of less than 5.0 × 103 cm−2. The lasers operate under pulsed operation mode at room temperature with a low threshold current density of 146.7 A cm−2.

The optimization of a SiO2/TiO2, SiO2/ZnS double layer antireflection coating (ARC) on Ga0.5In0.5P/In0.02Ga0.98As/Ge solar cells for terrestrial application is discussed. The Al0.5In0.5P window layer thickness is also taken into consideration. It is shown that the optimal parameters of double layer ARC vary with the thickness of the window layer.

Bi substitute DyIG thin films having high coercive force and good squareness have been prepared on glass substrates by sputtering. The Faraday rotation amounts to about 7.5°/μm at wavelength of 500 nm. The magnetic domains are stable after thermal magnetic recording. The interference of magnetooptical thin films is investigated when the surface of films is deposited with different metals. Using this charecteristics the optimum disign for garnet recording discs can be achieved.