Search results for: Gang Shen

Authors: Mengke Zhan, Cheng-Gang Xie, Jian-Jun Shu

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A venturi flowmeter is a common device used in multiphase flow rate measurement in the upstream oil and gas industry. Having a robust computational model for multiphase flow in a venturi is desirable for understanding the gas-liquid and fluid-pipe interactions and predicting pressure and phase distributions under various flow conditions. A steady Eulerian-Eulerian framework is used to simulate upward gas-liquid flow in a vertical venturi. The simulation results are compared with experimental measurements of venturi differential pressure and chord-averaged gas holdup in the venturi throat section. The choice of turbulence model is nontrivial in the multiphase flow modelling in a venturi. The performance cross-comparison of the k-ϵ model, Reynolds stress model (RSM) and shear-stress transport (SST) k-ω turbulence model is made in the study. In terms of accuracy and computational cost, the SST k-ω turbulence model is observed to be the most efficient.

Keywords: computational fluid dynamics (CFD), gas-liquid flow, turbulence modelling, venturi

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Authors: Hao Shen, Aparna Labroo

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Across four studies, we show people in a negative mood avoid anticipated enjoyable experiences because of the subjective difficulty in simulating those experiences, and they misattribute these feelings of difficulty to reduced pleasantness of the anticipated experience. We observe the avoidance of enjoyable experiences only for anticipated experiences that involve smile-like facial-muscular simulation. When the need for facial-muscular simulation is attenuated, or when the anticipated experience relies on facial-muscular simulation to a lesser extent, people in a negative mood no longer avoid enjoyable experiences, but rather seek such experiences because they fit better with their ongoing mood-repair goals.

Keywords: emotion regulation, mood repair, embodiment, anticipated experiences

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Authors: Gang Liu, Huimin Song, Can Wang, Runnan Zhang, Lu Fang

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Currently, resource sharing and system security are critical issues. This paper proposes a POL module composed of PRIV ILEGE attribute (PA), obligation and log which improves attribute based access control (ABAC) model in dynamically granting authorizations and revoking authorizations. The following describes the new model termed PABAC in terms of the POL module structure, attribute definitions, policy formulation and authorization architecture, which demonstrate the advantages of it. The POL module addresses the problems which are not predicted before and not described by access control policy. It can be one of the subject attributes or resource attributes according to the practical application, which enhances the flexibility of the model compared with ABAC. A scenario that illustrates how this model is applied to the real world is provided.

Keywords: access control, attribute based access control, granting authorizations, privilege, revoking authorizations, system security

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Authors: Jin Gang Lee, Hyun-Soo Lee, Moonseo Park

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The utilization of BIM and IFC allows project participants to collaborate across different areas by consistently sharing interoperable product information represented in a model. Comments or markups generated during the coordination process can be categorized as communication information, which can be shared in less standardized manner. It can be difficult to manage and reuse such information compared to the product information in a model. The present study proposes an interoperable coordination method using BCF (the BIM Collaboration Format) for managing and sharing the communication information during BIM based coordination process. A management function for coordination in the BIM collaboration system is developed to assess its ability to share the communication information in BIM collaboration projects. This approach systematically links communication information during the coordination process to the building model and serves as a type of storage system for retrieving knowledge created during BIM collaboration projects.

Keywords: design coordination, building information model, BIM collaboration format, industry foundation classes

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Authors: Zi-Gui Huang, Shen-Hsien Hu

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This study proposes a fabrication of phononic-crystal acoustic wave device. A graphene-like atomic structure was adopted as the main research subject, and a graphene-like structure was designed using piezoelectric material zinc oxide and its periodic boundary conditions were defined using the finite element method. The effects of a hexagonal honeycomb structure were investigated regarding the band gap phenomenon. The use of micro-electromechanical systems process technology to make the film etched micron graphics, designed to produce four kinds of different piezoelectric structure (plat, periodic, single defect and double defects). Frequency response signals and phase change were also measured in this paper.

Keywords: MEMS, phononic crystal, piezoelectric material, Zinc oxide

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Authors: J. R. Wang, Y. Chiang, W. S. Hsu, S. H. Chen, J. H. Yang, S. W. Chen, C. Shih, Y. F. Chang, Y. H. Huang, B. R. Shen

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In this research, the RASCAL code was used to simulate and analyze the postulated UF₆ fire accident which may occur in the Institute of Nuclear Energy Research (INER). There are four main steps in this research. In the first step, the UF₆ data of INER were collected. In the second step, the RASCAL analysis methodology and model was established by using these data. Third, this RASCAL model was used to perform the simulation and analysis of the postulated UF₆ fire accident. Three cases were simulated and analyzed in this step. Finally, the analysis results of RASCAL were compared with the hazardous levels of the chemicals. According to the compared results of three cases, Case 3 has the maximum danger in human health.

Keywords: RASCAL, UF₆, safety, hydrogen fluoride

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Authors: Jing-Gang Xie

Abstract:

The research, in this case, considers the integration of the Quantum Field Theory and the General Relativity Theory. As two successful models in explaining behaviors of particles, they are incompatible since they work at different masses and scales of energy, with the evidence that regards the description of black holes and universe formation. It is so considering previous efforts in merging the two theories, including the likes of the String Theory, Quantum Gravity models, and others. In a bid to prove an actionable experiment, the paper’s approach starts with the derivations of the existing theories at present. It goes on to test the derivations by applying the same initial assumptions, coupled with several deviations. The resulting equations get similar results to those of classical Newton model, quantum mechanics, and general relativity as long as conditions are normal. However, outcomes are different when conditions are extreme, specifically with no breakdowns even for less than Schwarzschild radius, or at Planck length cases. Even so, it proves the possibilities of integrating the two theories.

Keywords: general relativity theory, particles, photons, Quantum Gravity Model, gravitational frequency shift

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Authors: Hsien T. Hsieh, Chao R. Chen, Li C. Chuang, Chin C. Shen

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Fenton oxidation technology is the general strategy for the treatment of organic compounds-contained wastewater. However, a considerable amount of ferric sludge was produced during the Fenton process as secondary wastes, which were needed to be further removed from the effluent and treated. In this study, heterogeneous catalysts based on ferrite oxide (Cu-Fe-Ce-O) were synthesized and characterized, and their application for Fenton-like oxidation of simulated and actual radioactive organic wastewater was investigated. The results of TOC decomposition efficiency around 54% ~ 99% were obtained when the catalyst loading, H₂O₂ loading, pH, temperature, and reaction time were controlled. In this case, no secondary wastes formed and the given catalysts were able to be separated by magnetic devices and reused again.

Keywords: fenton, oxidation, heterogeneous catalyst, wastewater

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Authors: Jialin Wu, Zhiwei Lian, Jieyu Tang, Jingyun Shen

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Tornado is a serious and unpredictable natural disaster, which has an important impact on people's production and life. The probability of being hit by tornadoes in China was analyzed considering the principles of tornado formation. Then some suggestions on layout and shapes for newly-built buildings were provided combined with the characteristics of tornado wind fields. Fuzzy clustering and inverse closeness methods were used to evaluate the probability levels of tornado risks in various provinces based on classification and ranking. GIS was adopted to display the results. Finally, wind field single-vortex tornado was studied to discuss the optimized design of rural low-rise houses in Yancheng, Jiangsu as an example. This paper may provide enough data to support building and urban design in some specific regions.

Keywords: tornado probability, computational fluid dynamics, fuzzy mathematics, optimal design

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Authors: Xiao Yihong, Li Zhixuan, Wong Kah Seng, Shen Xingcang

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Requirement Elicitation is one of the important factors in developing any new application. Most systems fail just because of wrong elicitation practice. As a result, developers always choose different methods in different fields to achieve optimal results. This paper analyses four cases to understand the effectiveness of different requirement elicitation methods in the field of mobile shopping applications. The elicitation methods we studied included interviews, questionnaires, prototypes, analysis of existing systems, focus groups, brainstorming, and so on. Through the research and analysis results, we ensured the need for a mixture of elicitation methods. Meanwhile, the method adopted should be determined according to the scale of the project and be operated in a reasonable order to ensure the high efficiency of requirement elicitation.

Keywords: requirements elicitation method, shopping, mobile application, software requirement engineering

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Authors: Ji-Suk Kim, Dong-Pil Kim, Kee-Rae Gang, Yoon Ho Choi

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This study was conducted to investigate the characteristics of butterfly communities according to the habitat characteristics of Korean veins. The survey sites were 12 mountains located in the vein, and 12~30 quadrats (200 in total) were set. The species richness and biodiversity were different according to land use type. Two types of land use (forest and graveyard) showed lower species diversity index values ​​than other land use types. The species abundance was low in the forest and graveyards, and grasslands, forest tops, cultivated areas and urban areas showed relatively high species richness. The altitude was not statistically significant with the number of species of butterflies and biodiversity index. The degree of canopy closure showed a negative correlation. As a result of interspecific correlation analysis, it was confirmed that there was a very high correlation (R2=0.746) between Lycaena phlaeas and Pseudozizeeria maha argia, Choaspes benjaminii japonica and Argyronome ruslana.

Keywords: land use type, species diversity index, correlation, canopy closure

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Authors: Irfan Ullah Munir, Shen Yue, Muhammad Shahzad Ijaz, Saad Hussain, Syeda Yumna Zaidi

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Financial literacy is fundamental to every decision-making process and has received attention from researchers, regulatory bodies and policy makers in the recent past. This study is an attempt to evaluate financial literacy in an emerging economy, particularly Pakistan, and its influence on people's stock market participation. Data of this study was collected through a structured questionnaire from a sample of 300 respondents. EFA is used to check the convergent and discriminant validity. Data is analyzed using Hayes (2013) approach. A set of demographic control variables that have passed the mean difference test is used. We demonstrate that participants with financial literacy tend to invest more in the stock market. We also find that association among financial literacy and participation in stock market gets moderated by gender.

Keywords: Financial literacy, Stock market participation, Gender, PSX

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Authors: Wen-Yuh Jywe, Bor-Jeng Lin, Jing-Chung Shen, Jeng-Dao Lee, Hsueh-Liang Huang, Tung-Hsien Hsieh

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In this study, a simple 2-D measurement system based on optical design was developed to measure the motion errors of the linear guideway. Compared with the transitional methods about the linear guideway for measuring the motion errors, our proposed 2-D optical measurement system can simultaneously measure horizontal and vertical running straightness errors for the linear guideway. The performance of the 2-D optical measurement system is verified by experimental results. The standard deviation of the 2-D optical measurement system is about 0.4 μm in the measurement range of 100 mm. The maximum measuring speed of the proposed automatic measurement instrument is 1 m/sec.

Keywords: 2-D measurement, linear guideway, motion errors, running straightness

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Authors: Tabassum Husain, Shen Peng Li, Zhaolin Chen

Abstract:

This paper evaluates the usability of 3D Guided Image Filtering to enhance the quality of short-time binned dynamic PET images by using MRI images. Guided image filtering is an edge-preserving filter proposed to enhance 2D images. The 3D filter is applied on 1 and 5-minute binned images. The results are compared with 15-minute binned images and the Gaussian filtering. The guided image filter enhances the quality of dynamic PET images while also preserving important information of the voxels.

Keywords: dynamic PET images, guided image filter, image enhancement, information preservation filtering

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Authors: Shen Jian, Hu Jie, Zhu Guo Niu, Peng Ying Hong

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There are two issues exited in the traditional visual prosthesis: lacking systematic method and the low level of humanization. To tackcle those obstacles, a visual prosthesis design method based on biologically inspired design is proposed. Firstly, a constrained FBS knowledge cell model is applied to construct the functional model of visual prosthesis in biological field. Then the clustering results of engineering domain are ob-tained with the use of the cross-domain knowledge cell clustering algorithm. Finally, a prototype system is designed to support the bio-logically inspired design where the conflict is digested by TRIZ and other tools, and the validity of the method is verified by the solution scheme

Keywords: knowledge-based engineering, visual prosthesis, biologically inspired design, biomedical engineering

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Authors: Gang Liu, Can Wang, Runnan Zhang, Quan Wang, Huimin Song, Shaomin Ji

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Biba model can protect information integrity but might deny various non-malicious access requests of the subjects, thereby decreasing the availability in the system. Therefore, a mechanism that allows exceptional access control is needed. Break the Glass (BTG) strategies refer an efficient means for extending the access rights of users in exceptional cases. These strategies help to prevent a system from stagnation. An approach is presented in this work for integrating Break the Glass strategies into the Biba model. This research proposes a model, BTG-Biba, which provides both an original Biba model used in normal situations and a mechanism used in emergency situations. The proposed model is context aware, can implement a fine-grained type of access control and primarily solves cross-domain access problems. Finally, the flexibility and availability improvement with the use of the proposed model is illustrated.

Keywords: Biba model, break the glass, context, cross-domain, fine-grained

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Authors: Su-Ping Liu, Yue Tian, Yifan Shen

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This study investigates the effect of corporate governance on earnings management when firms have reported a long stream of earnings increases (hereafter referred to as earnings beaters). We expect that good quality of corporate governance decreases the probability of income-increasing earnings management. We employ transparent tools to capture firms’ opportunistic management behavior, specifically, the repurchase of stock. In addition, we use corporate governance proxies to measure the degree of corporate governance, including board size, board independence, CEO duality, and the frequency of meeting. The results hold after the controlling of variables that suggested in prior literature. We expect that the simple technique, that is, firms’ degree of corporate governance, to be used as an inexpensive first step in detecting earnings management.

Keywords: corporate governance, earnings management, earnings patterns, stock repurchase

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Authors: Ng Liang Shen, Hau Yuan Wen

Abstract:

Arrhythmia analysis of ECG signal plays a major role in diagnosing most of the cardiac diseases. Therefore, a single arrhythmia detection of an electrocardiographic (ECG) record can determine multiple pattern of various algorithms and match accordingly each ECG beats based on Machine Learning supervised learning. These researchers used different features and classification methods to classify different arrhythmia types. A major problem in these studies is the fact that the symptoms of the disease do not show all the time in the ECG record. Hence, a successful diagnosis might require the manual investigation of several hours of ECG records. The point of this paper presents investigations cardiovascular ailment in Electrocardiogram (ECG) Signals for Cardiac Arrhythmia utilizing examination of ECG irregular wave frames via heart beat as correspond arrhythmia which with Machine Learning Pattern Recognition.

Keywords: electrocardiogram, ECG, classification, machine learning, pattern recognition, detection, QRS

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Authors: S. Kazadi, A. An, B. Shen

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We investigate the fitness of a male and female permanent magnetic levitation support for use as an axle on a rotor for a levitating motor. The support enables passive thrust and axial support for the axle as a result of the unique arrangement of permanent magnets. As the axial and thrust bearing aspects are derived from magnetic repulsion, it is not immediately clear that the repulsion is stiff enough to enable even low power motors. This paper describes the design and performance of two low power motors based on the magnetic levitation support. We find that our low power motors, with rotational speeds of 618 and 833 rpms, exhibit performance free from excess vibrations that might hinder performance. This means that the actuation of the motors is adequately stabilized by the axle and results in motors capable of being utilized despite the levitation support.

Keywords: levitating motor, magnetic levitation support, fitness, axle

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Authors: B. R. Shen, J. R. Wang, J. H. Yang, S. W. Chen, C. Shih, Y. Chiang, Y. F. Chang, Y. H. Huang

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In this research, TRACE code with the interface code-SNAP was used to simulate and analyze the SBO (station blackout) accident which occurred in Maanshan PWR (pressurized water reactor) nuclear power plant (NPP). There are four main steps in this research. First, the SBO accident data of Maanshan NPP were collected. Second, the TRACE/SNAP model of Maanshan NPP was established by using these data. Third, this TRACE/SNAP model was used to perform the simulation and analysis of SBO accident. Finally, the simulation and analysis of SBO with mitigation equipments was performed. The analysis results of TRACE are consistent with the data of Maanshan NPP. The mitigation equipments of Maanshan can maintain the safety of Maanshan in the SBO according to the TRACE predictions.

Keywords: pressurized water reactor (PWR), TRACE, station blackout (SBO), Maanshan

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Authors: Shen Jian, Hu Jie, Ma Jin, Peng Ying Hong, Fang Yi, Liu Wen Hai

Abstract:

Biologically inspired design inspires inventions and new technologies in the field of engineering by mimicking functions, principles, and structures in the biological domain. To deal with the obstacles of cross-domain knowledge acquisition in the existing biologically inspired design process, functional semantic clustering based on functional feature semantic correlation and environmental constraint clustering composition based on environmental characteristic constraining adaptability are proposed. A knowledge cell clustering algorithm and the corresponding prototype system is developed. Finally, the effectiveness of the method is verified by the visual prosthetic device design.

Keywords: knowledge clustering, knowledge acquisition, knowledge based engineering, knowledge cell, biologically inspired design

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Authors: Mengjie Shen, Jianhua Wu, Chun Gan, Lifeng Zhang, Qingguo Sun

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Switching flux permanent magnet (SFPM) motor has doubly salient structure which lead to high torque ripple, and also has cogging torque as a permanent magnet motor. Torque ripple and cogging torque have impact on the motor performance. A novel stator structure SFPM motor is presented in this paper. A triangular shape silicon steel sheet is put in the stator slot to reduce the torque ripple, which will not deteriorate the cogging torque. The simulation of proposed motor is analyzed using 2-D finite element method (FEM) based on Ansoft and Simplorer software, and the result show a good performance of the proposed SFPM motor.

Keywords: switching flux permanent magnet (SFPM) motor, torque ripple, Ansoft, FEM

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Authors: G. Sivakumar, T. Pratyusha, D. Gupta, W. Shen

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To get ohmic contact between the cathode and organic semiconductor, transport layers are introduced between the active layer and the electrodes. Generally zinc oxide or titanium dioxide are used as electron transport layer. When electron transport layer is doped with lithium, the resultant film exhibited superior electronic properties, which enables faster electron transport. Doping is accomplished by heat treatment of films with Lithium salts. Li-doped films. We fabricated organic solar cell using PTB7(poly(3-hexylthiopene-2,5- diyl):PCBM(phenyl-C61-butyric acid methyl ester) and found that the solar cells prepared using Li doped films had better performance in terms of efficiency when compared to the undoped transport layers.

Keywords: electron transport layer, higher efficiency, lithium doping, ohmic contact

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Authors: Tsu-Wang Shen, Shan-Chun Chang, Chih-Hsien Wang, Te-Chao Fang

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For electrocardiogram (ECG) biometrics system, it is a tedious process to pre-install user’s high-intensity heart rate (HR) templates in ECG biometric systems. Based on only resting enrollment templates, it is a challenge to identify human by using ECG with the high-intensity HR caused from exercises and stress. This research provides a heartbeat segment method with slope-oriented neural networks against the ECG morphology changes due to high intensity HRs. The method has overall system accuracy at 97.73% which includes six levels of HR intensities. A cumulative match characteristic curve is also used to compare with other traditional ECG biometric methods.

Keywords: high-intensity heart rate, heart rate resistant, ECG human identification, decision based artificial neural network

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Authors: Le Fu, Rui Wu, Gang Feng Liu, Jie Zhao

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Normally, impedance control methods are based on a model that connects a spring and damper in parallel. The series connection, namely the Maxwell model, has emerged as a counterpart and draw the attention of robotics researchers. In the theoretical analysis, it turns out that the two pattern are both equivalents to some extent, but notable differences of response characteristics exist, especially in the effect of damping viscosity. However, this novel impedance control design is lack of validation on realistic robot platforms. In this study, stability analysis and experimental evaluation are achieved using a 3-fingered Barrett® robotic hand BH8-282 endowed with tactile sensing, mounted on a torque-controlled lightweight and collaborative robot KUKA® LBR iiwa 14 R820. Object handover and incoming objects catching tasks are executed for validation and analysis. Experimental results show that the series connection pattern has much better performance in natural impact or shock absorption, which indicate promising applications in robots’ safe and physical interaction with humans and objects in various environments.

Keywords: impedance control, Maxwell model, force control, dexterous manipulation

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Authors: Shabnam Dadparvar, Laijin Shen

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After a period of conflict between Russia and the West, new signs of confrontation between the United States and China are observed. China, as the most populous country in the world with a high rate of economic growth, neither stands the hegemonic power of the United States nor has the intention of direct confrontation with it. By raising the costs of the United States’ leadership at the international level, China seeks to find a better status without direct confrontation with the US. Meanwhile, the Shanghai Cooperation Organization (SCO), as a soft balancing strategy against the hegemony of the United States is used as a tool to reach this goal. The authors by using a descriptive-analytical method try to explain the policies of China and the United States on Shanghai Cooperation Organization as well as confrontation between these two countries within the framework of 'balance of soft power theory'.

Keywords: balance of soft power, Central Asia, Shanghai cooperation organization, terrorism

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Authors: Haizhong Zhang, Yan-Gang Zhao

Abstract:

Fundamental period, mode shape, and participation factor are important basic information for the understanding of earthquake response of ground. In this study, a simple approach is presented to calculate these basic information of layered soil profiles. To develop this method, closed form equations are derived for analysis of free vibration of layered soil profiles firstly, based on equilibrium between inertia and elastic forces. Then, by further associating with the Madera procedure developed for estimation of fundamental period, a simple method that can directly determine the fundamental period, mode shape and participation factor is proposed. The proposed approach can be conveniently implemented in simple spreadsheets and easily used by practicing engineers. In addition, the accuracy of the proposed approach is investigated by analyzing first vibration mode of 67 representative layered soil profiles, it is found that results by the proposed method agree very well with accurate results.

Keywords: layered soil profile, natural vibration, fundamental period, fundamental mode shape

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Authors: C. Ah Gang Getrude, Iqbal Hashmi Shazia, Mohd Nawi Nurul Hudani

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This study examined the effectiveness of a Traffic Psychology Workshop in enhancing positive attitudes towards road safety awareness among youths. We predicted that youths’ attitudes towards road safety would be more positive after they participated in the one-day workshop. We examined their attitudes towards road safety awareness before and after they attended a one-day workshop. There were 21 participants who completed the pre and post-studies (9 males & 12 females, mean age 22.86, SD=2.03). A Wilcoxon signed-ranks test showed that the mean for post-test ranks for students’ attitudes towards road safety awareness was higher than the mean pre-test ranks, z =-3.16, p = .00. The study showed that the Traffic Psychology Module which focuses on the three elements: i) personality & emotion; Sensation, perception and visual; and mental workload could have positive effects on youths’ attitudes towards road safety awareness. We believe that the Traffic Psychology Module could be used as a guide by relevant authorities, such as the Sabah Road Safety Department, in implementing road safety awareness workshops and programs for the public, particularly road-users.

Keywords: attitude, road safety, traffic psychology, youth

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Authors: Lixin Pei, Zhilong Huang, Wenzhe Gang

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Organic geochemistry of source rocks and oils in the Nanpu Sag, Bohai Bay basin was studied on the basis of the results of Rock-Eval and biomarker. The possible source rocks consist of the third member (Es₃) and the first member (Es₁) of Shahejie formation and the third member of Dongying Formation (Ed₃) in the Nanpu Sag. The Es₃, Es₁, and Ed₃ source rock intervals in the Nanpu Sag all have high organic-matter richness and are at hydrocarbon generating stage, which are regarded as effective source rocks. The three possible source rock intervals have different biomarker associations and can be differentiated by gammacerane/αβ C₃₀ hopane, ETR ([C₂₈+C₂₉]/ [C₂₈+C₂₉+Ts]), C₂₇ diasterane/sterane and C₂₇/C₂₉ steranes, which suggests they deposited in different environments. Based on the oil-source rock correlation, the shallow oils mainly originated from the Es₃ and Es₁ source rocks in the Nanpu Sag. Through hydrocarbon generation and expulsion history of the source rocks, trap development history and accumulation history, the shallow oils mainly originated from paleo-reservoirs in the Es₃ and Es₁ during the period of Neotectonism, and the residual paleo-reservoirs in the Es₃ and Es₁ would be the focus targets in the Nanpu Sag; Bohai Bay Basin.

Keywords: source rock, biomarker association, Nanpu Sag, Bohai Bay Basin

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Authors: Saad Nawaz, Yu Gang, Baber Saeed Olakh, M. Bilal Awan

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Owing to its exceptional performance and precision, laser drilling is being widely used in modern manufacturing industries. This experimental study mainly addressed the defocusing of laser beam along with different operational currents. The performance has been evaluated in terms of tapering phenomena, entrance and exit diameters etc. The operational currents have direct influence on laser power which ultimately affected the shape of the drilled hole. Different operational currents in low, medium and high ranges are used for laser drilling of 18CrNi8. Experiment results have depicted that there is an increase in entrance diameter with an increase in defocusing distance. However, the exit diameter first decreases and then increases with respect to increasing defocusing length. The evolution of drilled hole from tapered to straight hole has been explained with defocusing at different levels. The optimum parametric combinations for attaining perfect shape of drilled hole is proposed along with lower heat treatment effects for higher process efficiency.

Keywords: millisecond laser, defocusing beam, operational current, keyhole profile, recast layer

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