Search results for: Yong Wei Zhang
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1185

Search results for: Yong Wei Zhang

945 An Advanced Numerical Tool for the Design of Through-Thickness Reinforced Composites for Electrical Applications

Authors: Bing Zhang, Jingyi Zhang, Mudan Chen

Abstract:

Fibre-reinforced polymer (FRP) composites have been extensively utilised in various industries due to their high specific strength, e.g., aerospace, renewable energy, automotive, and marine. However, they have relatively low electrical conductivity than metals, especially in the out-of-plane direction. Conductive metal strips or meshes are typically employed to protect composites when designing lightweight structures that may be subjected to lightning strikes, such as composite wings. Unfortunately, this approach downplays the lightweight advantages of FRP composites, thereby limiting their potential applications. Extensive studies have been undertaken to improve the electrical conductivity of FRP composites. The authors are amongst the pioneers who use through-thickness reinforcement (TTR) to tailor the electrical conductivity of composites. Compared to the conventional approaches using conductive fillers, the through-thickness reinforcement approach has been proven to be able to offer a much larger improvement to the through-thickness conductivity of composites. In this study, an advanced high-fidelity numerical modelling strategy is presented to investigate the effects of through-thickness reinforcement on both the in-plane and out-of-plane electrical conductivities of FRP composites. The critical micro-structural features of through-thickness reinforced composites incorporated in the modelling framework are 1) the fibre waviness formed due to TTR insertion; 2) the resin-rich pockets formed due to resin flow in the curing process following TTR insertion; 3) the fibre crimp, i.e., fibre distortion in the thickness direction of composites caused by TTR insertion forces. In addition, each interlaminar interface is described separately. An IMA/M21 composite laminate with a quasi-isotropic stacking sequence is employed to calibrate and verify the modelling framework. The modelling results agree well with experimental measurements for bothering in-plane and out-plane conductivities. It has been found that the presence of conductive TTR can increase the out-of-plane conductivity by around one order, but there is less improvement in the in-plane conductivity, even at the TTR areal density of 0.1%. This numerical tool provides valuable references as a design tool for through-thickness reinforced composites when exploring their electrical applications. Parametric studies are undertaken using the numerical tool to investigate critical parameters that affect the electrical conductivities of composites, including TTR material, TTR areal density, stacking sequence, and interlaminar conductivity. Suggestions regarding the design of electrical through-thickness reinforced composites are derived from the numerical modelling campaign.

Keywords: composite structures, design, electrical conductivity, numerical modelling, through-thickness reinforcement

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944 The Co-Existence of Multidominance and Movement in the Syntax of Chinese Bi-Comparatives

Authors: Yaqing Hu

Abstract:

This paper puts forward a syntactic analysis involving multidominance and rightward movement in Chinese bi-comparatives, as in 'Yuehan bi Mali gao (John is taller than Mary).' It is argued here that the predicate of comparison is a shared constituent in two small clauses, namely one for the target and one for the standard; and then it moves rightward to form a degree phrase with the comparative morpheme. This proposal comes from four aspects. First, the example above can also be expressed in this way, 'A: Yuehan he Mali, shui gao? (John and Mary, who is taller?) B: Yuehan gao./Yuehan geng gao. (John is taller).' This shows that the gradable adjective is predicated of the target. In addition, according to a constraint on Chinese bi-comparatives, namely the target and the standard must be arguments of the predicate simultaneously, it is not unreasonable to assume that the gradable adjective may also be predicated of the standard. Second, subcomparatives are totally disallowed in Chinese, as in '*zhe-zhang zhuozi bi zhe-zhang yizi kuan chang. (This table is longer than this chair is wide.)' In order to save it from ungrammaticality, the target and the standard should be compared along the same dimension denoted by the gradable adjective. It may follow that in Chinese comparatives, having equal roles in the same eventuality, the target and the standard bear the same thematic relationship with the predicate of comparison. Third, verb-copy can appear in Chinese bi-comparatives, as in 'Yuehan qi ma bi Mali qi ma qi de kuai. (John rides horses faster than Mary does.)' The predicate qi seems to form a small clause with both the target and the standard. This might be supporting evidence that both the target and the standard share the predicate of comparison. Fourth, Chinese comparatives do have comparative morphemes, as in 'Yuehan bi Mali geng gao. (John is taller than Mary)', which is semantically equivalent to the first example above. Thus, it follows that one feature of Chinese comparative morphemes is that they can remain overt or covert in the syntax, which will not affect semantics. This further shows that comparative morphemes in bi-comparatives may not be able to saturate the degree argument denoted by the predicate of comparison due to its optionality in the structure. These four aspects present a challenge to the Direct Analysis used in Chinese comparatives since this approach would presume that the target and the standard somehow show independency with the predicate in the syntax. Meanwhile, this study also rejects the previous analysis of multidomiance in bi-comparatives in which the degree phrase comprised of the comparative morpheme and the gradable adjective may be shared by the standard when the comparative morpheme is covert. This syntactic analysis proposed in this study will therefore offer a different perspective of how to treat degree phrase in Chinese comparatives and may offer evidence to argue whether there is degree phrase movement in bi-comparatives as in its English counterparts.

Keywords: Chinese comparatives, degree phrase, movement, multidominance, syntactic analysis

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943 Economic Analysis of Domestic Combined Heat and Power System in the UK

Authors: Thamo Sutharssan, Diogo Montalvao, Wen-Chung Wang, Yong Chen, Claudia Pisac

Abstract:

A combined heat and power (CHP) system is an efficient and clean way to generate power (electricity). Heat produced by the CHP system can be used for water and space heating. The CHP system which uses hydrogen as fuel produces zero carbon emission. Its’ efficiency can reach more than 80% whereas that of a traditional power station can only reach up to 50% because much of the thermal energy is wasted. The other advantages of CHP systems include that they can decentralize energy generation, improve energy security and sustainability, and significantly reduce the energy cost to the users. This paper presents the economic benefits of using a CHP system in the domestic environment. For this analysis, natural gas is considered as potential fuel as the hydrogen fuel cell based CHP systems are rarely used. UK government incentives for CHP systems are also considered as the added benefit. Results show that CHP requires a significant initial investment in return it can reduce the annual energy bill significantly. Results show that an investment may be paid back in 7 years. After the back period, CHP can run for about 3 years as most of the CHP manufacturers provide 10-year warranty.

Keywords: combined heat and power, clean energy, hydrogen fuel cell, economic analysis of CHP, zero emission

Procedia PDF Downloads 359
942 A Study on the Implementation of Differentiating Instruction Based on Universal Design for Learning

Authors: Yong Wook Kim

Abstract:

The diversity of students in regular classrooms is increasing due to expand inclusive education and increase multicultural students in South Korea. In this diverse classroom environment, the universal design for learning (UDL) has been proposed as a way to meet both the educational need and social expectation of student achievement. UDL offers a variety of practical teaching methods, one of which is a differentiating instruction. The differentiating instruction has been pointed out resource limitation, organizational resistance, and lacks easy-to-implement framework. However, through the framework provided by the UDL, differentiating instruction is able to be flexible in their implementation. In practice, the UDL and differentiating instruction are complementary, but there is still a lack of research that suggests specific implementation methods that apply both concepts at the same time. This study was conducted to investigate the effects of differentiating instruction strategies according to learner characteristics (readiness, interest, learning profile), components of differentiating instruction (content, process, performance, learning environment), especially UDL principles (representation, behavior and expression, participation) existed in differentiating instruction, and implementation of UDL-based differentiating instruction through the Planning for All Learner (PAL) and UDL Lesson Plan Cycle. It is meaningful that such a series of studies can enhance the possibility of more concrete and realistic UDL-based teaching and learning strategies in the classroom, especially in inclusive settings.

Keywords: universal design for learning, differentiating instruction, UDL lesson plan, PAL

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941 E-Bike FE Model Analysis: Connection Stiffness of Elements with Different DOFs

Authors: Lele Zhang, Hui Leng Choo, Alexander Konyukhov, Shuguang Li

Abstract:

Finite Element (FE) model of simplified e-bike structure was generated by main frame with two tiers, which consisted of pipe, mass, beam, and shell elements (pipe 289, beam188, shell 181, shell 281, combin14, link11, mass21). These elements would be introduced and demonstrated using mathematical formulas. Based on coupling theory, constrain equations was proposed. Exporting all the parameters obtained from theory part, the connection stiffness matrix of the whole e-bike structure between each of these elements was detected.

Keywords: coupling theory, stiffness matrix, e-bike, finite element model

Procedia PDF Downloads 348
940 Optimum Design of Combine Threshing Cylinder for Soybean Harvest

Authors: Choi Duckkyu, Choi Yong, Kang Taegyoung, Jun Hyeonjong, Choi Ilsu, Hyun Changsik

Abstract:

This study was carried out to develop a soybean combine thresher that enables to reduce the damage rate of soybean threshing and the rate of unthreshing. The combine threshing cylinder was developed with 6 circular axis at each end and fixed with disc plates. It was attached to the prototype combine thresher. A combine thresher that has a cylinder with circular rod type threshing pegs was used for a comparative test. A series of comparative tests were conducted using dae-won soybean. The test of the soybean thresher was performed at the cylinder speeds of 210, 240, 270 and 300 rpm, and with the concave clearance of 10, 13 and 16 mm. The separating positions of soybean after threshing were researched on a separate box with 4 sections. The soybean positions of front, center, rear and rear outside, of 59.5%, 30.6%, 7.8% and 2.2% respectively, were obtained. At the cylinder speeds from 210 rpm to 300 rpm, the damage rate of soybean was increased from 0.1% to 4.2% correspondingly to speeds. The unthreshed rate of soybean under the same condition was increased from 0.9% to 4.1% correspondingly to speeds. 0.7% of the damage rate and 1.5% of the unthreshed rate was achieved at the cylinder speed of 240 rpm and with the concave clearance of 10 mm. For Daewon soybean, an optimum cylinder speed of 240 rpm and the concave clearance of 10 mm were identified. These results will be useful for the design, construction, and operation of soybean threshing harvesters.

Keywords: soybean harvest, combine threshing, threshing cylinder, optimum design

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939 A Study of the Relationship among the Hotel Staff's Work Stress, Perceived Organizational Support, and Work Efficacy: A Case Study of Macao

Authors: Zhang Tao, Si Tang, Zhang Yufeng, Jin Jiahua

Abstract:

Work pressure is an emerging research of organizational behavior. Many factors associated with this study also attracted the interest of scholars. Macao is surrounding by open micro-capitalist economy which has a high internationalization level and Mature operation system. And there is no doubt that tourism and hotel service industry is the pillar of the Macao economy with the developing of the mainland individual tourist visa. More and more cities are willing to inclusive culture diversity which lead to the amount of inbound tourists present high-speed up trend cause the hotel industry has a strong customer base and development space. At the same time, the hotel staff is an important role in the service. However, affected by some adverse factors, the hotel staff face a variety of pressures. This study combs the concept and theory of pressures relevant influencing factors and puts forward the purpose of this research. The focus of this study will be organizational supported by work efficiency and work pressure, using qualitative and quantitative research methods. Through questionnaires and interviews, 10 hotels in Macao were selected and 500 questionnaires were distributed to the employees. Statistical analysis software SPSS was used for descriptive statistics. By exploratory factor analysis and confirmatory factor analysis, effect. And the relevant practitioners on behalf of the interview content analysis. The innovation of this research lies in the empirical study of the relationship between the working pressure, organizational support and working efficiency of Macau hotel practitioners, and constructs and validates the structural model of the relationship among them. This model will be helpful for people to use more research methods to study hotel practitioners pressure in the future. At the same time, we can draw the following conclusions: 1. There is a significant negative correlation between salary level and job stress; 2. There is a significant negative correlation between job stress and performance; 3. Different organizational support can interfere the relationship between job stress and performance; 4. Put forward the strategy of relevance adjustment, which provides a reference value for the hotel industry in human resource management. It would be helpful to improve their service standard by training their practitioners more scientifically and rationally.

Keywords: Macau, perceived organizational support, work stress, work efficiency

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938 Real-Time Detection of Space Manipulator Self-Collision

Authors: Zhang Xiaodong, Tang Zixin, Liu Xin

Abstract:

In order to avoid self-collision of space manipulators during operation process, a real-time detection method is proposed in this paper. The manipulator is fitted into a cylinder enveloping surface, and then the detection algorithm of collision between cylinders is analyzed. The collision model of space manipulator self-links can be detected by using this algorithm in real-time detection during the operation process. To ensure security of the operation, a safety threshold is designed. The simulation and experiment results verify the effectiveness of the proposed algorithm for a 7-DOF space manipulator.

Keywords: space manipulator, collision detection, self-collision, the real-time collision detection

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937 Condensation of Vapor in the Presence of Non-Condensable Gas on a Vertical Tube

Authors: Shengjun Zhang, Xu Cheng, Feng Shen

Abstract:

The passive containment cooling system (PCCS) is widely used in the advanced nuclear reactor in case of the loss of coolant accident (LOCA) and the main steam line break accident (MSLB). The internal heat exchanger is one of the most important equipment in the PCCS and its heat transfer characteristic determines the performance of the system. In this investigation, a theoretical model is presented for predicting the heat and mass transfer which accompanies condensation. The conduction through the liquid condensate is considered and the interface temperature is defined by iteration. The parameter in the correlation to describe the suction effect should be further determined through experimental data.

Keywords: non-condensable gas, condensation, heat transfer coefficient, heat and mass transfer analogy

Procedia PDF Downloads 315
936 Synthesis of Nanoparticle Mordenite Zeolite for Dimethyl Ether Carbonylation

Authors: Zhang Haitao

Abstract:

The different size of nanoparticle mordenite zeolites were prepared by adding different soft template during hydrothermal process for carbonylation of dimethyl ether (DME) to methyl acetate (MA). The catalysts were characterized by X-ray diffraction, Ar adsorption-desorption, high-resolution transmission electron microscopy, NH3-temperature programmed desorption, scanning electron microscopy and Thermogravimetric. The characterization results confirmed that mordenite zeolites with small nanoparticle showed more strong acid sites which was the active site for carbonylation thus promoting conversion of DME and MA selectivity. Furthermore, the nanoparticle mordenite had increased the mass transfer efficiency which could suppress the formation of coke.

Keywords: nanoparticle mordenite, carbonylation, dimethyl ether, methyl acetate

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935 Evaluation of Ecological Resilience in Mountain-plain Transition Zones: A Case Study of Dujiangyan City, Chengdu

Authors: Zhu Zhizheng, Huang Yong, Li Tong

Abstract:

In the context of land and space development and resource environmental protection. Due to its special geographical location, mountain-plain transition zones are limited by many factors such as topography, mountain forest protection, etc., and their ecology is also more sensitive, with the characteristics of disaster susceptibility and resource gradient. Taking Dujiangyan City, Chengdu as an example, this paper establishes resilience evaluation indicators on the basis of ecological suitability evaluation through the analysis of current situation data and relevant policies: water conservation evaluation, soil and water conservation evaluation, biodiversity evaluation, soil erosion sensitivity evaluation, etc. Based on GIS spatial analysis, the ecological suitability and resilience evaluation results of Dujiangyan city were obtained by disjunction operation. The ecological resilience level of Dujiangyan city was divided into three categories: high, medium and low, with an area ratio of 50.81%, 16.4% and 32.79%, respectively. This paper can provide ideas for solving the contradiction between man and land in the mountain-plain transition zones, and also provide a certain basis for the construction of regional ecological protection and the delineation of three zones and three lines.

Keywords: urban and rural planning, ecological resilience, dujiangyan city, mountain-plain transition zones

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934 English Complex Aspectuality: A Functional Approach

Authors: Cunyu Zhang

Abstract:

Based on Systemic Functional Linguistics, this paper aims to explore the complex aspectuality system of English. This study shows that the complex aspectuality is classified into complex viewpoint aspect which refers to the homogeneous or heterogeneous ways continuously viewing on the same situation by the speaker and complex situation aspect which is the combined configuration of the internal time schemata of situation. Through viewpoint shifting and repeating, the complex viewpoint aspect is formed in two combination ways. Complex situation aspect is combined by the way of hypotactic verbal complex and the limitation of participant and circumstance in a clause.

Keywords: aspect series, complex situation aspect, complex viewpoint aspect, systemic functional linguistics

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933 Online Estimation of Clutch Drag Torque in Wet Dual Clutch Transmission Based on Recursive Least Squares

Authors: Hongkui Li, Tongli Lu , Jianwu Zhang

Abstract:

This paper focuses on developing an estimation method of clutch drag torque in wet DCT. The modelling of clutch drag torque is investigated. As the main factor affecting the clutch drag torque, dynamic viscosity of oil is discussed. The paper proposes an estimation method of clutch drag torque based on recursive least squares by utilizing the dynamic equations of gear shifting synchronization process. The results demonstrate that the estimation method has good accuracy and efficiency.

Keywords: clutch drag torque, wet DCT, dynamic viscosity, recursive least squares

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932 Experimental and Numerical Investigations of Impact Response on High-Speed Train Windshield

Authors: Wen Ma, Yong Peng, Zhixiang Li

Abstract:

Security journey is a vital focus on the field of Rail Transportation. Accidents caused by the damage of the high-speed train windshield have occurred many times and have given rise to terrible consequences. Train windshield consists of tempered glass and polyvinyl butyral (PVB) film. In this work, the quasi-static tests and the split Hopkinson pressure bar (SHPB) tests were carried out first to obtain the mechanical properties and constitutive model for the tempered glass and PVB film. These tests results revealed that stress and Young’s modulus of tempered glass were wake-sensitive to strain rate, but stress and Young’s modulus of PVB film were strong-sensitive to strain rate. Then impact experiment of the windshield was carried out to investigate dynamic response and failure characteristics of train windshield. In addition, a finite element model based on the combined finite element method was proposed to investigate fracture and fragmentation responses of train windshield under different-velocity impact. The results can be used for further design and optimization of the windshield for high-speed train application.

Keywords: constitutive model, impact response, mechanism properties, PVB film, tempered glass

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931 Development of a Scale for Evaluating the Efficacy of Vacationing

Authors: Ju Yeon Lee, Seol Ah Oh, Hong il Kim, Hae Yong Do, Sung Won Choi

Abstract:

The purpose of this study was to develop a Well-being and Moments Scale (WAMS) for evaluating the efficacy of ‘vacationing’ as a form of mental health recuperation. ‘Vacationing’ is defined as a going outside one’s usual environment to seek refreshment and relief from one’s daily life. To develop WAMS, we followed recommended procedures for scale development, including reviewing related studies, conducting focus group interviews to elucidate the need for this assessment area, and modifying items based on expert opinion. Through this process, we developed the WAMS. The psychometric properties of the WAMS were then tested in two separate samples. Exploratory factor analysis (EFA) was conducted using 1.41 participants (mean age = 30.45 years; range: 20-50 years) to identify the underlying 3-factor structure of 'Positive Emotions', 'Life Satisfaction' and 'Self-Confidence.' The 26 items retained based on the EFA procedures were associated with excellent reliability (i.e., α = 0.93). Confirmatory factor analysis was then conducted using 200 different participants (mean age = 29.51 years; range: 20-50 years) and revealed good model fit for our hypothesized 3-factor model. Convergent validity tests also revealed correlations with other scales in the expected direction and range. Study limitations as well as the importance and utility of WMAS are also discussed.

Keywords: vacationing, positive affect, life satisfaction, self-confidence, WAMS

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930 Effect of Oxidation on Wetting Behavior between Silicon and Silicon Carbide

Authors: Zineb Benouahmane, Zhang Lifeng

Abstract:

Experimental oxidation tests at high temperature (1300°C-1500°C) on α-SiC samples have been performed with different holding times and atmosphere (air, argon). Oxidized samples were then analyzed using X-ray photoelectron spectroscopy coupled to SEM and DAKTEK surface profiler verification. The oxidation rate and the mas gain were found to increase with temperature and holding times, corresponding to a passive oxidation regime which lead to the formation of SiO2 layer. The sessile drop method is employed in order to measure the wetting angles between Si/SiC system at high temperature (1430°C-1550°C). Contact angle can be varied between 44 °C to 85°C, by controlling the oxygen content in α-SiC. Increasing the temperature occurred the infiltration of liquid silicon and deoxidation of the coating.

Keywords: oxidation, wettability, silicon, SiC

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929 Boryl Radical-Promoted Dehydroxylative Alkylation of 3-Hydroxyoxindole Derivatives

Authors: Tesfaye Tebeka Simur, Tian-Yu Peng, Yi-Feng Wang, Xiu-Wei Wu, Feng-Lian Zhang

Abstract:

A boryl radical-promoted dehydroxylative alkylation of 3-hydroxy-oxindole derivatives is achieved. The reaction starts from addition of 4-dimethylaminopyridine (DMAP)-boryl radical to the amide carbonyl oxygen atom, which induces a spin-center shift process to promote the C−O bond cleavage. The elimination of a hydroxide anion from a free hydroxy group is also accomplished. Capture of the generated carbon radical with alkenes furnishes a variety of C-3 alkylated oxindoles. This method features a simple operation and broad substrate scope.

Keywords: boryl radical, C-O, C-F, C=C, C=N bond activation, spin center shift

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928 Accurate HLA Typing at High-Digit Resolution from NGS Data

Authors: Yazhi Huang, Jing Yang, Dingge Ying, Yan Zhang, Vorasuk Shotelersuk, Nattiya Hirankarn, Pak Chung Sham, Yu Lung Lau, Wanling Yang

Abstract:

Human leukocyte antigen (HLA) typing from next generation sequencing (NGS) data has the potential for applications in clinical laboratories and population genetic studies. Here we introduce a novel technique for HLA typing from NGS data based on read-mapping using a comprehensive reference panel containing all known HLA alleles and de novo assembly of the gene-specific short reads. An accurate HLA typing at high-digit resolution was achieved when it was tested on publicly available NGS data, outperforming other newly-developed tools such as HLAminer and PHLAT.

Keywords: human leukocyte antigens, next generation sequencing, whole exome sequencing, HLA typing

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927 Seismic Fragility of Base-Isolated Multi-Story Piping System in Critical Facilities

Authors: Bu Seog Ju, Ho Young Son, Yong Hee Ryu

Abstract:

This study is focused on the evaluation of seismic fragility of multi-story piping system installed in critical structures, isolated with triple friction pendulum bearing. The concept of this study is to isolate the critical building structure as well as nonstructural component, especially piping system in order to mitigate the earthquake damage and achieve the reliable seismic design. Then, the building system and multi-story piping system was modeled in OpenSees. In particular, the triple friction pendulum isolator was accounted for the vertical and horizontal coupling behavior in the building system subjected to seismic ground motions. Consequently, in order to generate the seismic fragility of base-isolated multi-story piping system, 21 selected seismic ground motions were carried out, by using Monte Carlo Simulation accounted for the uncertainties in demand. Finally, the system-level fragility curves corresponding to the limit state of the piping system was conducted at each T-joint system, which was commonly failure points in piping systems during and after an earthquake. Additionally, the system-level fragilities were performed to the first floor and second floor level in critical structures.

Keywords: fragility, friction pendulum bearing, nonstructural component, seismic

Procedia PDF Downloads 125
926 The Vertex Degree Distance of One Vertex Union of the Cycle and the Star

Authors: Ying Wang, Haiyan Xie, Aoming Zhang

Abstract:

The degree distance of a graph is a graph invariant that is more sensitive than the Wiener index. In this paper, we calculate the vertex degree distances of one vertex union of the cycle and the star, and the degree distance of one vertex union of the cycle and the star. These results lay a foundation for further study on the extreme value of the vertex degree distances, and the distribution of the vertices with the extreme value in one vertex union of the cycle and the star.

Keywords: degree distance, vertex-degree-distance, one vertex union of a cycle and a star, graph

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925 Preparation of Nb Silicide-Based Alloy Powder by Hydrogenation-Dehydrogenation (HDH) Reaction

Authors: Gi-Beom Park, Hyong-Gi Park, Seong-Yong Lee, Jaeho Choi, Seok Hong Min, Tae Kwon Ha

Abstract:

The Nb silicide-based alloy has the excellent high-temperature strength and relatively lower density than the Ni-based superalloy; therefore, it has been receiving a lot of attention for the next generation high-temperature material. To enhance the high temperature creep property and oxidation resistance, Si was added to the Nb-based alloy, resulting in a multi-phase microstructure with metal solid solution and silicide phase. Since the silicide phase has a low machinability due to its brittle nature, it is necessary to fabricate components using the powder metallurgy. However, powder manufacturing techniques for the alloys have not yet been developed. In this study, we tried to fabricate Nb-based alloy powder by the hydrogenation-dehydrogenation reaction. The Nb-based alloy ingot was prepared by vacuum arc melting and it was annealed in the hydrogen atmosphere for the hydrogenation. After annealing, the hydrogen concentration was increased from 0.004wt% to 1.22wt% and Nb metal phase was transformed to Nb hydride phase. The alloy after hydrogenation could be easily pulverized into powder by ball milling due to its brittleness. For dehydrogenation, the alloy powders were annealed in the vacuum atmosphere. After vacuum annealing, the hydrogen concentration was decreased to 0.003wt% and Nb hydride phase was transformed back to Nb metal phase.

Keywords: Nb alloy, Nb metal and silicide composite, powder, hydrogenation-dehydrogenation reaction

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924 Case-Based Reasoning Approach for Process Planning of Internal Thread Cold Extrusion

Authors: D. Zhang, H. Y. Du, G. W. Li, J. Zeng, D. W. Zuo, Y. P. You

Abstract:

For the difficult issues of process selection, case-based reasoning technology is applied to computer aided process planning system for cold form tapping of internal threads on the basis of similarity in the process. A model is established based on the analysis of process planning. Case representation and similarity computing method are given. Confidence degree is used to evaluate the case. Rule-based reuse strategy is presented. The scheme is illustrated and verified by practical application. The case shows the design results with the proposed method are effective.

Keywords: case-based reasoning, internal thread, cold extrusion, process planning

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923 Development of Configuration Software of Space Environment Simulator Control System Based on Linux

Authors: Zhan Haiyang, Zhang Lei, Ning Juan

Abstract:

This paper presents a configuration software solution in Linux, which is used for the control of space environment simulator. After introducing the structure and basic principle, it is said that the developing of QT software frame and the dynamic data exchanging between PLC and computer. The OPC driver in Linux is also developed. This driver realizes many-to-many communication between hardware devices and SCADA software. Moreover, an algorithm named “Scan PRI” is put forward. This algorithm is much more optimizable and efficient compared with "Scan in sequence" in Windows. This software has been used in practical project. It has a good control effect and can achieve the expected goal.

Keywords: Linux OS, configuration software, OPC Server driver, MYSQL database

Procedia PDF Downloads 257
922 Computational Fluid Dynamics Simulation Study of Flow near Moving Wall of Various Surface Types Using Moving Mesh Method

Authors: Khizir Mohd Ismail, Yu Jun Lim, Tshun Howe Yong

Abstract:

The study of flow behavior in an enclosed volume using Computational Fluid Dynamics (CFD) has been around for decades. However, due to the knowledge limitation of adaptive grid methods, the flow in an enclosed volume near the moving wall using CFD is less explored. A CFD simulation of flow in an enclosed volume near a moving wall was demonstrated and studied by introducing a moving mesh method and was modeled with Unsteady Reynolds-Averaged Navier-Stokes (URANS) approach. A static enclosed volume with controlled opening size in the bottom was positioned against a moving, translational wall with sliding mesh features. Controlled variables such as smoothed, crevices and corrugated wall characteristics, the distance between the enclosed volume to the wall and the moving wall speed against the enclosed chamber were varied to understand how the flow behaves and reacts in between these two geometries. These model simulations were validated against experimental results and provided result confidence when the simulation had shown good agreement with the experimental data. This study had provided better insight into the flow behaving in an enclosed volume when various wall types in motion were introduced within the various distance between each other and create a potential opportunity of application which involves adaptive grid methods in CFD.

Keywords: moving wall, adaptive grid methods, CFD, moving mesh method

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921 The Application of Green Technology to Residential Architecture in Hangzhou

Authors: Huiru Chen, Xuran Zhang

Abstract:

At present, the residential architecture in China are still causing high energy consumption and high pollution during their whole life cycle, which can be backward compared with the developed countries. The aim of this paper is to discuss the application of green technology to residential architecture in Hangzhou. This article will start with the development of green buildings, then analyzes the use status of green technology in Hangzhou from several specific measures. Analysis of the typical existing green residential buildings in Hangzhou is an attempt to form a preliminary Hangzhou’s green technology application strategy system. Through research, it has been found that the application of green technology in Hangzhou has changed from putting green to the facade, to the combination of the preservation of the traditional green concept and the modern green technology.

Keywords: application, green technology, Hangzhou, residential architecture

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920 The Synthesis of AgInS₂/SnS₂ Nanocomposites with Enhanced Photocatalytic Degradation of Norfloxacin

Authors: Mingmei Zhang, Xinyong Li

Abstract:

AgInS₂/SnS₂ (AIS) nanocomposites were synthesized by a simple hydrothermal method. The morphology and composition of the fabricated AIS nanocomposites were investigated by field-emission scanning electron microscopy (SEM), X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM) and X-ray photoelectron spectroscopy (XPS). Moreover, the as-prepared AIS photocatalysts exhibited excellent photocatalytic activities for the degradation of Norfloxacin (NOR), mainly due to its high optical absorption and separation efficiency of photogenerated electron-hole pairs, as evidenced by UV–vis diffusion reflection spectra (DRS) and Surface photovoltage (SPV) spectra. Furthermore, the interfacial charges transfer mechanism was also discussed by DFT calculations.

Keywords: AIS nanocomposites, electron-hole pairs, charges transfer, DFTcaculations

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919 The Effectiveness of Sulfate Reducing Bacteria in Minimizing Methane and Sludge Production from Palm Oil Mill Effluent (POME)

Authors: K. Abdul Halim, E. L. Yong

Abstract:

Palm oil industry is a major revenue earner in Malaysia, despite the growth of the industry is synonymous with a massive production of agro-industrial wastewater. Through the oil extraction processes, palm oil mill effluent (POME) contributes to the largest liquid wastes generated. Due to the high amount of organic compound, POME can cause inland water pollution if discharged untreated into the water course as well as affect the aquatic ecosystem. For more than 20 years, Malaysia adopted the conventional biological treatment known as lagoon system that apply biological treatment. Besides having difficulties in complying with the standard, a large build up area is needed and retention time is higher. Although anaerobic digester is more favorable, this process comes along with enormous volumes of sludge and methane gas, demanding attention from the mill operators. In order to reduce the sludge production, denitrifiers are to be removed first. Sulfate reducing bacteria has shown the capability to inhibit the growth of methanogens. This is expected to substantially reduce both the sludge and methane production in anaerobic digesters. In this paper, the effectiveness of sulfate reducing bacteria in minimizing sludge and methane will be examined.

Keywords: methane reduction, palm oil mill effluent, sludge minimization, sulfate reducing bacteria, sulfate reduction

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918 Effects of Dietary Supplementation with Fermented Feed Mulberry(Morus alba L.) on Reproductive Performance and Fecal M Icro Biota of Pregnant Sows

Authors: Yuping Zhang, Teng Ma, Nadia Everaert, Hongfu Zhang

Abstract:

Supplying dietary fiber during gestation is known to improve the welfare of feed-restricted sows. However, whether high fiber supplementation during pregnancy can improve the performance of sows and their offspring depends on the type, amount, source, etc., in which the solubility plays a key important role. Insoluble fibers have been shown to increase feed intake of sows in lactation, meet the needs of sows for milk production, reduce sow’s weight and backfat loss, and thus improve the performance of sows and their offspring. In this study, we investigated the effect of the addition of fermented feed mulberry (FFM), rich in insoluble fiber, during the whole gestation on the performance of sows and their offspring and explored possible mechanisms by determining serum hormones and fecal microbiota. The FFM-diet contained 25.5% FFM (on dry matter basis) and was compared with the control–diet (CON, corn, and soybean meal diet). The insoluble fiber content of the FFM and CON diet are respectively 29.3% and 19.1%. both groups were allocated 20 multiparous sows, and they are fed different feed allowance to make sure all the sows get the same digestible energy for each day. After farrowing, all sows were fed the same lactation diet ad libitum. The serum estradiol, progesterone concentration, blood glucose, and insulin levels at gestation day 0, 20, and 60 were tested. And also, the composition and differences fecal microbiota at day 60 of gestation were analyzed. Fecal consistency was determined with Bristol stool scale method, those with a score below 3 were counted as constipation The results showed that there was no impact of the FFM treatment on sows’ backfat, bodyweight changes, blood glucose, serum estradiol, and progesterone concentration, litter size, and performance of the offspring(p > 0.05), Except significant decrease in the concentration of insulin in sows’ serum at 60 days of gestation were observed in the FFM group compare to the CON group (P < 0.01). FFM diet also significantly increased feed intake on the first, third, and 21st days of sow lactation. (p < 0.01); The α- and β- diversity and abundance of the microbiota were significant increased (p < 0.01) compared with the CON group, The abundance of Firmicutes and Bacteroidetes were significantly increased, meanwhile the abundances of Spirochetes, Proteobacteria, and Euryarchaeota, were significantly reduced in the feces of the FFM group. We also analyzed the fecal microbiota of constipated sows vs non-constipated sows and found that the diversity and abundance did also differ between these two groups. FFM and CON group < 0.01). The relationship between sow’s constipation and microbiota merits further investigation.

Keywords: fermented feed mulberry, reproductive performance, fecal flora, sow

Procedia PDF Downloads 121
917 Reflection Phase Tuning of Graphene Plasmons by Substrate Design

Authors: Xiaojie Jiang, Wei Cai, Yinxiao Xiang, Ni Zhang, Mengxin Ren, Xinzheng Zhang, Jingjun Xu

Abstract:

Reflection phase of graphene plasmons (GPs) at an abrupt interface is very important, which determines the plasmon resonance of graphene structures of deep sub-wavelength scales. However, at an abrupt graphene edge, the reflection phase is always a constant, ΦR ≈ π/4. In this work, we show that the reflection phase of GPs can be efficiently changed through substrate design. Reflection phase of graphene plasmons (GPs) at an abrupt interface is very important, which determines the plasmon resonance of graphene structures of deep sub-wavelength scales. However, at an abrupt graphene edge, the reflection phase is always a constant, ΦR ≈ π/4. In this work, we show that the reflection phase of GPs can be efficiently changed through substrate design. Specifically, the reflection phase is no longer π/4 at the interface formed by placing a graphene sheet on different substrates. Moreover, tailorable reflection phase of GPs up to 2π variation can be further achieved by scattering GPs at a junction consisting of two such dielectric interfaces with various gap width acting as a Fabry-Perot cavity. Besides, the evolution of plasmon mode in graphene ribbons based on the interface reflection phase tuning is predicted, which is expected to be observed in near-field experiments with scattering-type scanning near-field optical microscopy (s-SNOM). Our work provides another way for in-plane plasmon control, which should find applications for integrated plasmon devices design using graphene.Specifically, the reflection phase is no longer π/4 at the interface formed by placing a graphene sheet on different substrates. Moreover, tailorable reflection phase of GPs up to 2π variation can be further achieved by scattering GPs at a junction consisting of two such dielectric interfaces with various gap width acting as a Fabry-Perot cavity. Besides, the evolution of plasmon mode in graphene ribbons based on the interface reflection phase tuning is predicted, which is expected to be observed in near-field experiments with scattering-type scanning near-field optical microscopy (s-SNOM). Our work provides a new way for in-plane plasmon control, which should find applications for integrated plasmon devices design using graphene.

Keywords: graphene plasmons, reflection phase tuning, plasmon mode tuning, Fabry-Perot cavity

Procedia PDF Downloads 122
916 The Catalytic Properties of PtSn/Al2O3 for Acetic Acid Hydrogenation

Authors: Mingchuan Zhou, Haitao Zhang, Hongfang Ma, Weiyong Ying

Abstract:

Alumina supported platinum and tin catalysts with different loadings of Pt and Sn were prepared and characterized by low temperature N2 adsorption/desorption, H2-temperature programed reduction and CO pulse chemisorption. Pt and Sn below 1% loading were suitable for acetic acid hydrogenation. The best performance over 0.75Pt1Sn/Al2O3 can reach 87.55% conversion of acetic acid and 47.39% selectivity of ethanol. The operating conditions of acetic acid hydrogenation over 1Pt1Sn/Al2O3 were investigated. High reaction temperature can enhance the conversion of acetic acid, but it decreased total selectivity of ethanol and acetyl acetate. High pressure and low weight hourly space velocity were beneficial to both conversion of acetic acid and selectivity to ethanol.

Keywords: acetic acid, hydrogenation, operating condition, PtSn

Procedia PDF Downloads 324