Advanced Materials Research Vols. 301-303

Abstract: For its advantages of simple structure and low cost, turbine flow sensor has been widely applied in gas and liquid transportation and other industries for measuring liquid or gas flowrate. Firstly, the output pulse signal property of turbine flow sensor was studied. To achieve the dynamic response, a new turbine flow sensor which based on the photoelectric detection is designed in this paper. In addition, experimental testing on the turbine flow sensor has been carried out on standard calibration facilities with high accuracy. The results confirm that the design is feasible, and the repeatability error is about 0.5%, the maximum relative error is less than 1%.

Abstract: Voxel-based morphometry method (VBM) has been widely applied to detect the brain atrophy and achieved promising results; however, the effect of the segmentation step in VBM is not clear and the new segmentation method in SPM8 hasn’t been used in Alzheimer’s disease (AD) studies. The aim of this study is to investigate the locations and degrees of grey matter (GM), white matter (WM) atrophy and evaluate the results derived from two segmentation methods. Magnetic resonance imaging (MRI) was collected in 16 AD patients and 16 healthy controls (HC). Using two segmentation methods respectively, several reduction clusters of GM and WM were detected but the locations and degrees of reduction volumes were discrepant resulted from different segmentation methods. Our results suggest that VBM is an effective tool to analyze AD brain atrophy and based on VBM, the comparison of the locations and degrees of volume reduction among AD researches through different segmentation methods should be cautious.

Abstract: We propose a new method aiming at solving the volume measurement problem of the complex-shaped cavity of a workpiece. We first use machine vision technology to obtain the external geometric parameters, and then calculate the external volume of the workpiece through integral principle. Next, we calculate the solid-part volume of the workpiece by dividing its weight by its specific gravity. Finally, by subtracting the solid-part volume from the external volume of the workpiece, we obtain the volume of the inner cavity. The experimental results show that the precision of our method is higher than 0.5%, and the time consumed is less than 20 seconds.

Abstract: Nowadays, the parallel system performance evaluation is the hot spot topic. It’s helpful to improve the parallel system performance to establish a scientific evaluation model. In this paper, using of analytic hierarchy process and the fuzzy mathematics theory, the multi-level fuzzy synthetic evaluation model is established, the performance index system is defined and the parallel system performance evaluation process is realized.

Abstract: This study is based on a typical residual soil landslide adjacent to Daxishan Reservior in Dalian city of China. By drilling the original samples in the field and remodeling the copy samples in the laboratory, a series of geotechnical experiments are carried out by the improved direct shear apparatus to obtain the changing law between the shear strength and water content of the mixed slide-zone soils. Emphasis is given on the shear stress-strain behavior and the corresponding constitutive model under different water content for the soils. Especially, the typical fitting equation is achieved to reflect the state of shear stress-normal stress-water content, some strain softening and hardening behavior on the mixed slide-zone soils of landslide is also discussed in detail. The results indicate that the shear strength is significantly related to water content of mixed slide-zone soils of landslide. The bigger water content of slide-zone soil is, the smaller the shear strength of soils is. When water content of mixed slide-zone soils approaches to certain value (i.e., 15%), the curve of shear stress and displacement shows a remarkable softening behavior, and the shear strength has marked a peak value.

Abstract: Clinically, basic physiological signal measurement, such as cardiovascular vibration and respiration motion detection, reveals important vital information of clinical diagnosis or personal health status evaluation. In routine, there are many preferable non-invasive methods, including electrocardiogram (ECG), pressure-sensitive transducers and applanation tonometry, to get insight of the sign of life. However, the operation of traditional monitors is relied on professionals’ experience, and also the sensing probes needed to contact to the user’s skin directly. The measurement procedure is easy to cause inconvenient and uncomfortable. To improve the issues of these measuring techniques, the non-contact and non-invasive measuring method will become an important innovation. In this paper, the novel nanosecond pulse near-field sensing (NPNS) based screening technology, which includes radio frequency (RF) pulse transmission and a flat antenna connected to transceiver of miniature radar, is proposed to monitor physical activity inside body. A dedicate analysis software built in Smartphone is also provided to calculate desired parameters, including heart rate and breath rate, for clinical or common personal applications. To evaluate the performance, the proposed method was applied on motion measurement at the body site of chest. As a result, the proposed method is validated to perform the capability of continuously long-term monitoring to reveal cardiovascular information in real-time.

Abstract: The capability to withstand non-contact underwater explosions (UNDEX) is an important aspect to be emphasized in the design of modern warships, and shock testing is one of the efficient methods to qualify the ability. A brief history on the research of shock testing of naval shipboard equipment as well as major means in evaluating anti-shock performance of warship equipment is introduced first in this paper. Three prevailing shock test methods: UNDEX testing, virtual shock trial and land-based test with shock test machines are presented with the focus on the advances in shock test machines in US and Europe. Comparison of current shock testing facilities is also given. Moreover, some new concepts of shock test machines are reviewed as well, and three major directions of the development of shock test machines are concluded. The first trend is that shock testing machines are required to generate positive and negative shock pulse to simulate real UNDEX environment made up of shock wave followed by bubble pulse and structural whipping. The second is that shock test machines can test heavy equipments, and the last is that shock pulses can be controlled and customized conveniently.

Abstract: In order to predict the effects of gas volume and mass inertia of explosion doors on overpressure for venting of gas explosion, a numerical method are used to simulate some situations of venting devices such as panels or explosion doors. The numerical data are in good agreement with the experiments of panels given an overpressure peak. A set of experiments were carried out in a 10 m3 silo and methane is used as fuel. The results of measurement in experiments indicated that the inertial mass of explosion door has a possibility of causing considerable damage and has effected on the rate of opening vented door and the pressure rise in such the experimental silo.

Abstract: Loudness is one of the most important parameters of psychoacoustics. In the past, most loudness models were applicable only to steady sounds. However, most everyday sounds are time-varying. Moore and coworkers described a time-varying loudness model based on Moore’s Loudness model. In this paper, a detailed calculation of Moore’s time-varying loudness model is given. The model using the time waveform of a sound which is picked up by the microphone as its input is implemented in Visual C++. The results which are compared with LabVIEW and ANSI show that the system is feasible.

Abstract: This paper describes the low power test challenges and features of a multi-core processor, Godson-T, which contains 16 identical cores. Since the silicon design technology scales to ultra deep submicron and even nanometers, the complexity and cost of testing is growing up, and the test power of such designs is extremely curious, especially for multicore processors. In this paper, we use the modular design methodology and scaleable design-for-testability (DFT) structure to achieve low test power, at the same time, an improved test pattern generation method is studied to reduce test power further more. The experimental results from the real chip show that the test power and test time are well balanced while achieving acceptable test coverage and cost.