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The overset grid assembly (OGA) method is an effective computational fluid dynamics technique for the simulation of flows with complex geometries or relative moving parts. Using OGA, the effort for...

In recent years, changes in the commercial sector, along with the growing popularity of the Internet, have made Malaysian businesses increasingly conscious of the relevance of E-business in establishing a competitive advantage in the worldwide market. As a result, a greater knowledge of the elements that impact online purchase intent might aid in the development of more effective marketing strategies for certain segments. Four variables affecting online purchase intent were chosen for this study: trust, product and service quality, customer satisfaction, and delivery time. Three factors substantially affected online purchase intention, according to 203 Generation X respondents. The only exception was the quality of the product and service. Researchers, online platform developers, financial institutions, marketers, and the government would benefit greatly from the data and information gathered in this study since we will be able to assess and understand the variables that influence Gen X in Malaysia to purchase online.

In view of the dynamic instability of rock mass in high geostress areas during underground engineering excavation, the comprehensive weight and extension methods are adopted to research the rockburst prediction. Firstly, five main influencing factors including uniaxial compressive strength, stress coefficient, brittleness coefficient, elastic energy index, and integrity of rock mass are used as the evaluation indexes of rockburst prediction according to the conditions required for rockburst occurrence. The assessment index system of rockburst intensity is constituted. Secondly, the analytic hierarchy process (AHP) and variation coefficient methods are used to determine the comprehensive weight of evaluation index, and the rockburst prediction model is established based on the extension evaluation method. Thirdly, the parameter programming and numerical calculation of the proposed prediction model are carried out in the MATLAB software. The user visualization execution window and software system of rockburst prediction model are realized. Finally, the software system is applied to the rockburst prediction in the water diversion tunnels of Jiangbian hydropower station and Jinping secondary hydropower station. The prediction results are compared with the actual situation and other evaluation methods. The results show that (i) the establishment of the user visualization window realizes the visualization and systematization of rockburst prediction model, which improves the data import rate and calculation efficiency. (ii) The prediction results of the proposed software system agree well with the actual situation, and they are more accurate than other evaluation methods. (iii) The proposed software system of rockburst prediction can also be used in coal mine, metro, and other underground projects, which has good engineering application values.

Mechanization and automation of the coal industry as well as increasing the government support for safety in coal mines in China resulted in a significant decrease in the death rate per million tons of coal produced. Nonetheless, major accidents still occur. As one of the five factors of safe production, safety investment plays a key role in ensuring the safe production of coal in mining enterprises. Coal mining enterprises can ensure safe production in the mines and maximize profits through optimum safety investment. In this study, safety system engineering principles and subsets in set theory were combined to develop a novel safety investment index system. The safety investment indices were categorized into human, machine, environment, and the intersection of these three indices. The elements in each investment set were examined, and a multivariate model of safety investment and accident control was created using gray forecasting theory. In addition, a case study was conducted to validate the reliability of the model. The results indicated that the proposed model can provide theoretical evidence and guidance for safety investment decision making in coal mining enterprises.

Energy storage technology is critical for intelligent power grids. It has great significance for the large-scale integration of new energy sources into the power grid and the transition of the energy structure. Based on the existing technology of isothermal compressed air energy storage, this paper presents a design scheme of isothermal compressed air energy storage power station, which uses liquid to compress air, hydraulic piston to transfer potential energy, hydraulic turbine to generate electricity at constant pressure, and liquid occupancy to store the gas at constant pressure. Then the technical features and control strategies of its internal temperature control subsystem are studied, and the mathematical model is constructed. A hierarchical relay operation is put forward to address the actual construction and operational requirements of compressed air energy storage power plants. Finally, through physical platform experiments and MATLAB simulation, the feasibility of the design is validated.

We report that transparent polymer coatings imprinted with tilted planar waveguides significantly reduce optical loss caused by the scattering of incident light by front metal contacts of solar cel...

We propose a novel stereo vision method based on a fast template matching strategy to improve localization accuracy and efficiency of substation fittings. First, considering the salient features of the substation fittings that can be recognized easily, the method searches for features that are similar to the ones in the matching template related to the sub-image of the substation fittings from the global image. When the substation fittings are confirmed, the method repeatedly searches for the one of screw holes in the local region of the substation fittings. It then computes the centering coordinates of the template in the source images until the screw holes are matched. The experimental results show that the proposed template matching method increases the accuracy and efficiency of the substation fitting localization from the global to local search area. Correspondingly, the accuracy and efficiency of stereo vision localization of substation fittings is improved.

Wafer defect classification is essential in semiconductor manufacturing for fast response of equipment and process stability monitoring, it is also critical for product yield management. Manual defect classification is time-consuming and prone to errors. This study presents an automatic defect classification (ADC) method based on a deep convolution neutral network (DCNN) model. The trained model has proven itself to be able to achieve defect classification performance sufficiently good to serve in the Fab.

Evidence of the association between common chronic diseases and depression is sparse.Totally 7819 participants aged 45+ without depression at baseline were followed-up (2011-2015) to detect incident depression. Chronic diseases and depression were defined by self-reported diagnosis and the Center for Epidemiological Studies Depression Scale (CES-D10), respectively. Cox proportional hazards model was used to explore the association between chronic diseases and depression adjusting for age, gender, education, marital/living conditions, area, smoking, drinking, economic status, BMI and health insurance.During an average of 3.42 years follow-up, 2271 participants developed depression (85 per 1000 person-year). Chronic diseases were related to significantly higher risk of depression (HR = 1.38). A higher risk of depression was also associated with specific diseases: stomach/other digestive diseases (HR = 1.19), diabetes (HR = 1.22), arthritis/rheumatism (HR = 1.30), and kidney diseases (HR = 1.34) (P0.05). The risk of depression increased with increasing in the number of chronic diseases (1: HR = 1.27, 2: HR = 1.49, and 3+: HR = 1.51, P-trend0.001). No significant difference was observed across age, gender, education, and area.Chronic diseases and depression were based on self-reported diagnosis and measurement scale, respectively, which could lead to information bias. Some unmeasured confounders might have biased the results.The occurrence of depression in people aged 45+ is associated with number of chronic diseases in a dose-response fashion. These results may provide guidance on preventing depression and improving the quality of life in middle and late adulthood.

Background Depressive symptoms and cognitive impairment often coexisted in the elderly. This study investigates the effect of late-life depressive symptoms on risk of mild cognitive impairment (MCI). Methods A total of 14,231 dementia- and MCI free participants aged 60+ from the Survey of Health, Ageing, and Retirement in Europe were followed-up for 10 years to detect incident MCI. MCI was defined as 1.5 standard deviation (SD) below the mean of the standardized global cognition score. Depressive symptoms were assessed by a 12-item Europe-depression scale (EURO-D). Severity of depressive symptoms was grouped as: no/minimal (score 0–3), moderate (score 4–5), and severe (score 6–12). Significant depressive symptoms (SDSs) were defined as EURO-D score ≥ 4. Results During an average of 8.2 (SD = 2.4)-year follow-up, 1,352 (9.50%) incident MCI cases were identified. SDSs were related to higher MCI risk (hazard ratio [HR] = 1.26, 95% confidence intervals [CI]: 1.10–1.44) in total population, individuals aged 70+ (HR = 1.35, 95% CI: 1.14–1.61) and women (HR = 1.28, 95% CI: 1.08–1.51) in Cox proportional hazard model adjusting for confounders. In addition, there was a dose–response association between the severity of depressive symptoms and MCI incidence in total population, people aged ≥70 years and women (p-trend Conclusions Significant depressive symptoms were associated with higher incidence of MCI in a dose–response fashion, especially among people aged 70+ years and women. Treating depressive symptoms targeting older population and women may be effective in preventing MCI.

In semiconductor manufacturing, defects detecting and analyzing are one of the key contributors for process yield improvement. A system is proposed to classify the defects automatically, which is more efficient than traditional manual work. It becomes possible to control the process promptly. The proposed system has three main parts, the defect image pre-process module, the defect classification module and the network results post-process module. The convolutional neural network (CNN) is used as the base algorithm for defect classification. And the post-process part is developed to refine the confusing images results. The dataset in this work are all collected from the 12-inch process line and the results show that the system proposed is a good candidate for saving massive human work.

Microfiber optic array structures are fabricated and employed as an optical structure overlaying a front-contact silicon solar cell. The arrays are synthesized through light-induced self-writing in a photo-crosslinking acrylate resin, which produces periodically spaced, high-aspect-ratio, and vertically aligned tapered microfibers deposited on a transparent substrate. The structure is then positioned over and sealed onto the solar cell surface. Their fiber optic properties enable collection of non-normal incident light, allowing the structure to mitigate shading loss through the redirection of incident light away from contacts and toward the solar cell. Angle-averaged external quantum efficiency increases nominally by 1.61%, resulting in increases in short-circuit current density up to 1.13 mA/cm2. This work demonstrates a new approach to enhance light collection and conversion using a scalable, straightforward, light-based additive manufacturing process.

The structure of the ear is one of the most important features of cereals associated with such agronomically important traits as productivity, resistance to environmental factors and pests, threshebility. Ears differ in shape, size, density, awnedness, color, etc. Analysis of the ear traits requires visual inspection, manual measurements and is very time-consuming. The effectiveness of ears’ phenotyping can be improved by the introduction of an automated image processing technology, storage of information in databases, use of machine learning algorithms to analyze this information. This paper presents a new approach for collecting, storing and analyzing of information about morphometric characteristics of ears of wheat. Two protocols for obtaining digital images of the ear have been developed. The computer-aided information system SpikeDroidDB has been developed, which allows you to store digital images of the ear, annotate their phenotypic features (14 features, including plant variety description, links to parent genotypes, generation, planting number, ear morphology description). The interface provides a flexible query system to access the data. SpikeDroidDB represents an interconnected representation between genotype, phenotype, location, and growing conditions. The web interface of SpikeDroidDB is available at http://spikedroid.biores . cytogen.ru/ and allows you to work with the system as with desktop computers or mobile devices. We used SpikeDroidDB for the digitization and annotation of a collection of ears of F 2 hybrids from crosses between the Australian cultivar of common wheat Triple Dirk and accession KU506 of Chinese wheat Triticum yunnanense. This experiment includes analysis of 104 plants, 230 spike images. The analysis of the variability of ears in form, length, and other traits allowed determination of the type of their genetic control: compactness is controlled by two recessive genes, awn type and hairi ness at the site of attachment of the spikelet to the axis is controlled by single dominant gene type, hairiness on the axis of the spike is controlled by two dominant genes.

We report a study on the growth kinetics and resultant structures of arrays of pillars in photo-cross-linkable films during irradiation with a periodic array of microscale optical beams under ambient conditions. The optical beams experience a self-focusing nonlinearity owing to the photopolymerization-induced changes in refractive index, thereby concentrating light and driving the concurrent, parallel growth of microscale pillars along their path length. We demonstrate control over the pillar spacing and pillar height with the irradiation intensity, film thickness, and the size and spacing of the optical beams. The growth of individual pillars in a periodic array arises from the combination of intense irradiation in the beam regions and oxygen inhibition afforded by the open, ambient conditions under which growth is carried out. We propose a kinetic model for pillar growth that includes free-radical generation and oxygen inhibition in thick films of photoinitiated media in order to interpret the experimen...

In this paper, high-efficiency low-filling-factor sheet beam extended interaction oscillator (SB-EIO) with an improved ladder structure is discussed. The Ka-band cavity with nine gaps is designed to operate at $2\pi $ mode. A sheet beam (8 mm $\times $ 0.6 mm) of 34 kV and 3.5 A is injected into SB-EIO through a beam tunnel of $12~\text {mm}\times 1.2$ mm. The axial electric field distribution and the synchronization conditions are optimized to improve the beam-wave interaction efficiency. An effective method is explored and utilized to suppress the mode competition. A stable output power of 35.9 kW and 30% efficiency are obtained for a 0.56 filling factor in narrow direction and 0.67 filling factor in wide direction. An output power of 22.8 kW and 19.1% efficiency are also attained even with a 0.4 filling factor in narrow direction and 0.67 filling factor in wide direction.

Background There were different voices about the accuracy of self-reported data. This study was to assess awareness and accuracy of self-reported height, weight and waist circumference (WC) among adult residents in rural poor areas of China for the first time. Methods Multi-stage stratified cluster random sampling was used to sample. Intraclass correlations (ICCs), Bland-Altman plots with limits of agreements (LOAs), Cohen’s kappa were used to examine the accuracy. Multi-factor Logistics and multiple linear regression were used to explore the effect of demographic and socioeconomic variables. Results Awareness rate of height, weight and WC were 66.29%, 82.29% and 60.00%, respectively. Height was over-reported 0.67 cm, weight and WC were under-reported 0.00 kg and 1.09 cm. ICC for height was 0.92, weight was 0.93 and WC was 0.93. Mostly differences were within 95% LOAs, but 95% LOAs were wide, especially WC. The percentage agreement (kappa) for BMI was 82.10% (0.71), for WC were 83.56% (0.66). Overall, obesity, overweight and increased WC were underestimated by 0.56%, 2.64% and 6.89%, respectively. Regression analysis showed some demographic and socioeconomic variables could affect the awareness and accuracy. Conclusions The self-reported height and weight could be used in rural poor areas of China, but the WC should be used with caution. The main task now is to further improve the awareness rate and accuracy of self-reported data, especially the people with low awareness rate and accuracy in certain subgroups. In addition, differences from the developed countries should be more discussed and investigated: all others showed people tend to under-reported weight, but the self-reported weight is amazingly accurate in our study; and contrary to studies in developed county, we found people tend to under-report WC.

To evaluate the effectiveness of a mobile health (mHealth) application, based on self-regulation theory, on patients' knowledge of wound care, skills in changing dressings and anxiety.A prospective randomized controlled trial.Seventy patients (or family members) at a 1,500-bed university hospital in Taiwan were randomized into an experimental (N = 35) or control group (N = 35) from March to December 2016. The experimental group used a mHealth application for wound care; the control group received verbal instructions and a booklet. Instruments to collect data were a wound care knowledge scale, wound care skills scale, State-Trait Anxiety Inventory, and a digital heart variability device. Data were collected at baseline, after three additional demonstrations and before discharge. The generalized estimating equation was used for statistical analysis.The experimental group showed significantly higher levels of wound care knowledge, improved wound care skills, lower levels of state anxiety, and lower heart rate variability than the control group after baseline data collection.Results support hat a mHealth application may be effective in health education. Clinicians can use the results to promote patients' wound care knowledge, enhance their wound care skills, and reduce anxiety related to dressing changes.Lack of wound care knowledge and skills can affect the willingness and ability to perform effective wound dressing changes, producing anxiety and having an impact on a patient's self-care after hospital discharge. mHealth applications (apps) have the potential to deliver health information in targeted and tailored ways that strengthen the self-management of diseases. mHealth app can increase wound care knowledge, improve care skills, and reduce anxiety related to wound care. mHealth app effectively supports self-monitoring of the wound healing process, self-judgement of the wound condition, and self-reaction of wound care accuracy. mHealth app provides step-by-step visual tutorials on wound care that allow patients and family caregivers to take pictures of the wounds and monitor the wound healing process. mHealth app for wound care knowledge is an effective and individualized method for learning.This study was registered by U.S. National Library of Medicine, ClinicalTrials.gov (ID: NCT03683303).目的: 基于自我调节理论,评估移动医疗(mHealth)应用程序对患者伤口护理知识、换药技能和焦虑程度的作用。 设计: 一项前瞻性随机对照试验 方法: 2016年3月至2016年12月,台湾一所拥有1,500张床位的大学附属医院的70名患者(或家属)被随机分为实验组(N = 35)或对照组(N = 35)。实验组使用移动医疗(mHealth)应用程序申请进行伤口护理;对照组收到口头指示和小册子。数据采集工具包括伤口护理知识量表、伤口护理技能量表、状态特质焦虑问卷和数字式心率变异装置。数据收集时间点是治疗前的基础值、三次额外演示后和出院前。采用广义估计方程进行统计分析。 结果: 在进行基础数据收集之后,实验组的伤口护理知识水平、伤口护理技能改善情况、状态特质焦虑水平和心率变异性均显著高于对照组。 结论: 研究结果支持移动医疗(mHealth)应用程序在健康教育中的有效性。临床医生可利用这些结果来加强患者的伤口护理知识,提高他们的伤口护理技能,降低与换药相关的焦虑。 影响: 缺乏伤口护理知识和技能会影响患者进行有效伤口换药的意愿和能力,使患者产生焦虑,并影响患者出院后的自我护理。移动医疗(mHealth)应用程序(apps)有可能提供具有针对性的定制化健康信息,从而加强患者对疾病的自我管理。移动医疗(mHealth)应用程序可以增加患者的伤口护理知识,提高护理技能,降低与伤口护理相关的焦虑。移动医疗(mHealth)应用程序可有效支持伤口愈合过程的自我监控、伤口状况的自我判断以及伤口护理准确性的自我反应。移动医疗(mHealth)应用程序可提供有关伤口护理的分步式可视化教程,允许患者和家庭护理提供者拍摄伤口照片并监控伤口愈合过程。移动医疗(mHealth)伤口护理知识应用程序是一种有效的个性化学习方法。 临床试验: 该研究在美国国立医学图书馆ClinicalTrials.gov注册(编号:NCT03683303)。.

A 320×256 readout integrated circuit (ROIC) with a pixel pitch of 30μm is presented for solar-blind AlGaN ultraviolet focal array plane (FPA). Capacitor feedback transimpendance amplifier (CTIA) has been selected as the input structure of the ROIC because of its excellent performance. A novel cascade amplifier with a symmetrical differential input stage is designed for input stage of CTIA, and an ultra-low capacitance with a value of 10fF is in the feedback loop of the amplifier as integral capacitor. Furthermore, the ROIC read out in a rolling shutter mode by using cascade D flip-flops. The ROIC has been fabricated 0.35μm 2P4M mixed signal CMOS process and interfaced with AlGaN solar-blind ultraviolet focal array plane (UVFPA). The test result shows that 320×256 AlGaN UVFPA has a wide dynamic range of 88.2dB with 5V power supply and has a high injection efficiency of 98.2%.

We report on the fabrication of an open cellular solid structure using visible light photocuring in combination with light-induced self-writing. A visible light sensitive photopolymer is irradiated with multiple arrays of microscale optical beams, which are generated from LEDs. These beams undergo self-trapping and elicit the inscription of microscale, solid struts into the medium. This process creates a structure consisting of multiple, intersecting struts that form a microtruss structure. Such structures retain their elasticity at higher temperatures as compared to a bulk film of the same thickness. This is the first demonstration of visible light photocuring of photopolymers into a microtruss structure, as well as investigation into their elastic properties under tension. Keywords: Polymers, Self-trapping, Microstructures, Cellular solids

With the development of urbanization, the ecological environment of the typical agro-development city-Weinan is disturbed to varying degrees, and it restricts the coordinated development of resources, population and environment in the region. This paper combines social, economic and climate data to propose an index system suitable for the evaluation of ecological vulnerability in Weinan. The analytic hierarchy process was used to quantitatively evaluate the ecological vulnerability of the Weinan region. The results showed that from 2000 to 2011, the urban ecological vulnerability index(EVI) was higher than that of the surrounding counties, which had a great relationship with the impact of urbanization on ecological vulnerability. The extremely fragile areas of ecological vulnerability in Weinan were mainly distributed in the urban areas of Linwei District and Hancheng. The main reason was that these cities had a fast development speed and a strong industrial base, which had a great impact on the ecological vulnerability.

In recent years, Hydro-pneumatic cycling compressed air energy storage (HC-CAES) has become an important topic in compressed air energy storage (CAES) technology research. In HC-CAES, air is compressed by liquid and driven by electrical equipment when energy is stored, and then, liquid is used to drive the water conservancy equipment to generate electricity. In this study, adaptive hydraulic potential energy transfer technology is proposed to solve a series of problems in the HC-CAES system, including the high fluctuation range of gas potential energy, poor operating stability, low efficiency, and so on. Therefore, fluctuating potential energy can be stably transferred through the variable area hydraulic devices, which can be controlled with an on&ndash, off valve. The structure and operation scheme of the adaptive hydraulic potential energy transfer device used in the HC-CAES system are explained in detail, the device can provide a stable water head range for the highly efficient operation of water conservancy equipment. Moreover, an optimal operation scheme was determined through simulation analysis, a physical experiment platform was built to verify the feasibility of the design and stability of system operation.

To determine the safety and feasibility of percutaneous transhepatic cholangiography (PTC) and intraductal radiofrequency (RF) ablation combined with biliary stent placement for malignant biliary obstruction.Data from patients with unresectable malignant biliary obstruction who underwent PTC, intraductal RF ablation, and biliary stent placement (n = 12) or PTC and biliary stent placement only (control group; n = 14) were reviewed. Postoperative complications, jaundice remission, and stent patency were assessed.All procedures were successful. No severe complications (eg, biliary bleeding, perforation) occurred. Two experimental group patients developed cholangitis, which resolved with conservative treatment. The 1-week jaundice remission and 3-month stent patency rates were similar in both groups, but the 6-month stent patency rate was higher in the experimental group (P.05). In the experimental group, one death occurred as a result of gastrointestinal hemorrhage (unrelated to stent placement) by 3 months, and there were two cases of recurrent jaundice by 6 months. The latter two patients underwent repeat PTC, ablation, and stent placement. In the control group, one death occurred as a result of hepatic failure caused by progressive jaundice at 3 months, and another death resulted from disseminated intravascular coagulation caused by jaundice recurrence at 138 days after stent placement. In addition, seven patients developed jaundice recurrence (50-151 d after stent placement). PTC and repeat stent placement were performed in these patients.Percutaneous transhepatic cholangiography and intraductal RF ablation combined with biliary stent placement for malignant biliary obstruction is safe and feasible and effectively prolongs stent patency time.

The relationship of frequency shift and glucose concentration was determined by microwave perturbation theory, and a measurement system was designed. The sensing device is a cylindrical cavity working at 7 GHz with TE011 mode. The glucose solution is placed in a capillary tube that is in the middle of the cavity. The geometrical parameters of the coupling device are optimized to make the system perform better. The radius of the capillary is 2 mm, which guarantees the volume of the capillary tube, being small enough to be neglected when concentration changes. Three modules: detecting, tracking and measuring module based on FPGA help monitor frequency change. The resolution of the system reaches up to 10 mg/dl which is promising for measuring blood glucose in the future.

Distribution network is an important part of power system, the biggest feature of the structure is that the end of power network is directly connected to the users, demanding for safety and quality. This article introduces the low voltage distribution network operation theory, designs a low-voltage wiring mode, and by analyzing the disadvantages of this kind of connection, the optimal switching looped network operation is put forward; at the end of the low voltage distribution network flow calculation, by comparing the results of the loop closing operation with the open loop operation, the feasibility and advantages of loop operation is proved.

This paper proposes a scheme of the looped network applied to low-voltage distribution network and introduces the control strategy for looped network in the normal event of a distribution network failure. Besides, the paper shows the superiority of the looped network in reducing the outage time and improving the power distribution reliability.

Gesture-recognition is an important component for many intelligent human---computer interaction applications. For example, a realtime sign-language recognition system would detect and interpret hand gestures. Many vision-based sign-language recognition methods have been proposed over the years with mix results of usability. Some system are limited to recognize only a few gestures, while others require the use of 3D camera to provides depth information to improve recognition accuracy. In this paper, a Kinect-based Taiwanese sign-language recognition system is proposed. Three main features are extracted from the signing gestures, namely hand positions, hand signing direction, and hand shapes. The hand positions are readily available through the input sensor. The signing direction is determined using HMM on trajectory of the hand movement, and a SVM is trained and used to recognize the hand shapes. Experimental results show that the proposed system achieved an 85.14 % recognition rate.

For energy-saving and consumption-reducing, new energy-saving transformer becomes more and more important. Via an economic evaluation methodology called Total Owning Cost (TOC), this article compares energy-saving transformer with high-energy transformer for examples in the angle of transformer loss and picks up the optimum energy-efficient transformer which can be expected to gain more benefit during transformer life cycle. This article also analyses cost of silicon steel sheet used in the transformer core and benefit in Total Owning Cost (TOC) of upgrading silicon steel sheet which primarily reduces no-load loss. Based on calculated results of Total Owning Cost (TOC) and payback period, the new energy-efficient transformer replacement plan, economic discussion and promotion proposal are brought up.

This paper introduces the method of braking system design for FSAE racing car. Based on the rules of FSAE, the requirements of braking performance were analyzed and the layout was confirmed. The forces of the braking system were analyzed under different braking strengths. The simulation results show that the ?design of the braking system ?can ?meet the strength requirements. Key words: Design ; Simulation ;FSAE; Racing car

Mixed amine solvents have become research trend as their great performance of decarbonization in recent years. The kinetics model was established and fitted to the experimental data. Then the reaction kinetics of mixed solvents of MDEA and enamine in CO2 absorption process were analyzed through model. The results showed that the optimum concentration of absorbent and operating temperature exists in single MDEA system. As for mixed amine systems, the CO2 absorption capacity was stronger as the DETA or TETA dosages were greater. The model prediction accuracy for single MDEA solvent was better while the model prediction accuracy for 2.0 MDEA/1.0 DETA was decreased. When absorption rate was slower, the reaction was more close to the pseudo first order, and then the prediction accuracy of the model was higher. The research in this paper can promote the industrial applications of mixed amine solvents.

This paper presents a novel image trading mechanism based on hybrid watermarking techniques. The removable visible watermarking technique is used to provide the safe preview of the protected media. The fingerprinting is used to trace the illegal distributor. Two kinds of watermarking techniques embed watermarks in DCT domain in order to conform to compression techniques. Experimental results show that image trading mechanism based on hybrid watermarking techniques can protect the image with high quality.

The aim of the current study was to assess effectiveness of automatic braking system quantitatively using real pedestrian accident data selected from IVAC database. Based on the IVAC pedestrian accident scenarios, vehicle and pedestrian trajectories, and other information, the relative position of vehicles and pedestrians were estimated one second (0.5 second) prior to the actual crash. According to the pedestrian fatal (AIS3+) risk and compared with the real pedestrian casualty risk, the benefit of the automatic braking system was calculated. About 86.8% (82.3%) reduction in pedestrian fatal (AIS3+) injury at a field of view of 60°.

Silicon solar cells are the most widely deployed modules owing to their low-cost manufacture, large market, and suitable efficiencies for residential and commercial use. Methods to increase their solar energy collection must be easily integrated into module fabrication. We perform a theoretical and experimental study on the light collection properties of an encapsulant that incorporates a periodic array of air prisms, which overlay the metallic front contacts of silicon solar cells. We show that the light collection efficiency induced by the encapsulant depends on both the shape of the prisms and angle of incidence of incoming light. We elucidate the changes in collection efficiency in terms of the ray paths and reflection mechanisms in the encapsulant. We fabricated the encapsulant from a commercial silicone and studied the change in the external quantum efficiency (EQE) on an encapsulated, standard silicon solar cell. We observe efficiency enhancements, as compared to a uniform encapsulant, over the visible to near infrared region for a range of incident angles. This work demonstrates exactly how a periodic air prism architecture increases light collection, and how it may be designed to maximize light collection over the widest range of incident angles.

Base on the study of interactive collaborative learning system, a construction program of a knowledge-centric interactive collaborative learning system is proposed. The program adopts the knowledge point as the smallest element of teaching resource library, and constructs knowledge model through the relationship between knowledge points. In this paper, the course Computer Organization Principles is taken as an example to build knowledge point repository which is with a certain applicable value and be of guiding significance for the subsequent collaborative learning research.

Optimal Viewing Distance (OVD) is a basic and important auto-stereoscopic 3D (AS3D) display characteristic. A number of studies, especially in the 3D display design and metrology fields, have mentioned this item for a long time. Unfortunately, there have been few theoretical and empirical studies on OVD. In this paper, we study OVD based on designer's formula, and geometrical and ray tracing approaches are applied to the simulation and measured data. We find that the OVD no more exist in practical cases, and we suggest the thought OVD should be modified by designated eye position (DEP).

We propose a model to quantify the crosstalk phenomenon for stereoscopic and autostereoscopic displays, separate crosstalk contributed from co-location image contrast (CIC) and system crosstalk (SCT), introduce gray scale dependency of CIC, modify model for gray scale dependency of SCT in active type 3D displays, and apply the model to derive the 3D luminance and SCT measurement formulas. The model might serve as a basis for the 3D metrology, and the results of this research should be of reference value to hardware makers and inspectors of stereoscopic and autostereoscopic displays.

The optimal viewing distance was proposed as a parameter for designing a parallax barrier 3D display. It can be designed based on simple geometric method and by considering the pitches of image display pixels and parallax barrier, or even including the aperture ratios of the image display pixels and parallax barrier. It can be analyzed by using ray tracing method. By considering the optical refraction index of the cover glass, the angular behavior of the system becomes more realistic; however, the geometric method is difficult to be used. We propose a revised method for estimating the view distance and angular behavior. In this paper, we have demonstrated a designated eye position (DEP) for each view and shown that multiple DEPs make a circular curve around the center of the display. We prove the new concept by comparing the optical ray tracing calculations and optical measurement.

A near eye holographic display using light-emitted diode (LED) instead of laser diode as the reconstruction light source has been proposed. An off-axis illumination architecture on a phase modulation only liquid crystal on silicon(LCoS) panel is used for investigating the influence of LED source property on the reconstruction image quality.

With the development and formation of networked and digital campus, the characteristic of diversification and complicated have been founded in student’s learning behavior. At the same time, for more broad application of web technology, promoted the ascension of teaching effect and reformation on education teaching method. In this paper a new evaluation analysis model about student's study quality based on web was proposed, and in this model, and in this model the correlation analysis algorithm has been used to verified the danamic relationship between analysis model and student performance, with the description of core technology in this model the validity and practicability of teaching quality monitoring process in the level student was proved.

In this paper a cavity resonator system based on microwave perturbation theory which is used for measuring the relative permittivity of material has been presented. The cavity works with the frequency of 7GHz and TE011 is chosen as the working mode to avoid other perturbing modes. After calculating and analyzing rectangle waveguide WR-112 is chosen to feed energy for the cavity. The radii of coupling aperture and radii of capillary are optimized. Results show that aperture radius=4mm and capillary=2.6mm make the system perform better. Five different samples are filled in the capillary to verify the performance of the cavity and the cavity resonator is highly sensitive to the change of dielectric constant of materials and it can be used for characterizing and studying dielectric character of materials.

Crosstalk is an important factor in determining image quality of stereoscopic display. Traditional system crosstalk model, evaluated for both time-sequential and spatially stereoscopic displays, is not suitable for time-sequential 3D display. A modified gray-to-gray crosstalk model for time-sequential stereoscopic display is proposed and evaluated with comparing in this study, and it shows the new model is more close to the crosstalk in reality.

Nowadays, the contents associated with deep score analysis is rarely involved in the existing secondary teaching management software, which is not conductive to fully develop the information implied by these data,without scientific teaching evaluation. Using data mining technology, multiple aspects of student score distribution will be shown accurately, identifying the regular factors affecting score changes. Standard score as the mathematical model is adopted in the system, choosing the standard SOA architecture model, and a scientific and efficient score analysis system based on JAVA, JSP is developed. The system provides decision support information for academic departments to promote better teaching work, and finally improve the quality of teaching.

The virtual reality technology is a three-dimensional virtual environment composed by computer hardware, software and various of sensors. It creates an unprecedented wealth of content and more fantastic teaching environment which reflects strong advantage in experiment and practice. In accordance with the needs of experiment teaching, multi-level interrupt virtual experiment environment is studied combining with the characteristics of its principle. The experiment environment is based on Tec-xp test box designed and developed by Tsinghua University computer factory. Microsoft Visual C++6.0 language is adopted for software platform development. Seen from the system needs analysis, object-oriented simulation method is adopted for modeling in this experiment environment. Meanwhile combining with computer system features and the characteristics of Computer Organization Principle teaching, the basic theory and methods of discrete event system simulation are used, which make the operation of virtual environment the same as on real device.

The structure, characteristics and use of MCM69C432 are introduced in the paper, based upon which a virus search scheme is proposed aiming at its characteristics. Through constructing CAM rule matching unit, the package head and data load are filtered parallelly, and the filtered results are handled centralizely according to the rule response requirements. It makes the system more powerful in processing and applicability, which has a good application prospect.