Search results

The purpose of this paper is to study the influence of friction coefficient of materials with different elastic modulus on the variation of velocity and load under water lubrication and oil lubrication conditions.

Low-viscosity lubricating oil and water were used as lubricants to test the friction performance of the ball-disc contact friction pair in the lubrication state on the universal micro-tribometer multi-functional friction and wear test system.

In the same speed range, the lubrication states from soft to rigid materials are not necessarily similar to each other. Generally, the material with low elastic modulus is suitable in low-viscosity lubricant environments, while the material with high elastic modulus has relatively smaller friction coefficients in oil-lubricated environments compared with water lubrication. However, the coefficients of polyethylene, polytetrafluoroethylen and polyoxymethylene are exceeded by rubber’s coefficients under water lubrication in the same experiment environments, and their lubrication states are not affected by lubricants. The friction coefficient of the friction pair decreases with the increase of loads; however, it does not apply to all materials. The friction coefficients of materials with smaller elastic modulus such as rubber under high loads are rather large. Therefore, the elastic modulus of the material under high loads is a factor to be considered.

The Stribeck curves study of the ball-disk contact friction pair comprising soft and rigid materials, whose elastic modulus is from hundreds of GPa to a few of MPa, was carried out. The influence of different speeds, loads and lubricants on the friction coefficient of the friction pair was revealed, which provided a research basis for the selection and matching of friction pair materials.

The high-pressure accumulator has been widely used in the hydraulic system. Failure pressure prediction is crucial for the safe design and integrity assessment of the accumulators. The purpose of this study is to accurately predict the burst pressure and location for the accumulator shells due to internal pressure.

This study concentrates the non-linear finite element simulation procedure, which allows determination of the burst pressure and crack location using extensive plastic straining criterion. Meanwhile, the full-scale hydraulic burst test and the analytical solution are conducted for comparative analysis.

A good agreement between predicted and measured the burst pressure that was obtained, and the predicted failure point coincided very well with the fracture location of the actual shell very well. Meanwhile, the burst pressure of the shells increases with wall thickness, independent of the length. It can be said that the non-linear finite element method can be employed to predict the failure behavior of a cylindrical shell with sufficient accuracy.

This paper can provide a designer with additional insight into how the pressurized hollow cylinder might fail, and the failure pressure has been predicted accurately with a minimum error below 1%, comparing the numerical results with experimental data.

Man has been seeking an ideal existence for a very long time. In this existence, justice, love, and peace are no longer words, but actual experiences. How ever, with the American preemptive invasion and occupation of Afghanistan and Iraq and the subsequent prisoner abuse, such an existence seems to be farther and farther away from reality. The purpose of this work is to stop this dangerous trend by promoting justice, love, and peace through a change of the paradigm that is inconsistent with justice, love, and peace. The strong paradigm that created the strong nation like the U.S. and the strong man like George W. Bush have been the culprit, rather than the contributor, of the above three universal ideals. Thus, rather than justice, love, and peace, the strong paradigm resulted in in justice, hatred, and violence. In order to remove these three and related evils, what the world needs in the beginning of the third millenium is the weak paradigm. Through the acceptance of the latter paradigm, the golden mean or middle paradigm can be formulated, which is a synergy of the weak and the strong paradigm. In order to understand properly the meaning of these paradigms, however, some digression appears necessary.

The purpose of this paper is to report the investigation of a low temperature application process for three‐layer polyethylene coating (3LPE) at 185‐195°C to meet the requirement of the coating temperature for X80 longitudinally welded pipe.

Plant coating and laboratory tests were performed to determine the properties of 3LPE coating coated at 185‐195°C.

The properties of the 3LPE coating, which was applied by using a suitable low temperature cured epoxy powder at temperature of 185‐195°C, were nearly the same as those of a 3LPE coating that had been applied at the normal coating temperature (200‐230°C).

Recommended acceptance criteria for 3LPE coatings applied at 185‐195°C are proposed. The research results met the requirements for external anti‐corrosion properties for X80 longitudinally welded pipe.

Polymeric coatings and packaging are often used to enhance the temperature sensitivity of fiber Bragg grating temperature sensors. The high thermal expansion coefficient of the polymer enhances the thermal sensitivity by improving the wavelength shift due to thermal expansion. The adhesion of the polymeric coatings to the silica based optical fiber plays an important role in the wavelength response characteristics of fiber Bragg gratings with respect to temperature. Experiments are done to qualitatively analyze the influence of adhesion. Three‐dimensional finite element simulations have been carried out. Spring elements are used to interconnect the nodes of the meshed models of optical fiber and coating. The effect of adhesion is studied as a function of spring stiffness.

The purpose of this paper is to investigate Chinese consumers’ willingness-to-pay (WTP) for fair trade coffee given different amount of product information. Although coffee is becoming more popular in China, the concept of fair trade is often found unfamiliar to most Chinese consumers.

A total of 564 consumers were interviewed in Hubei, China. The key survey question asked consumers’ willingness to purchase a cup of fair trade coffee compared to a traditional cup of coffee. A modified payment card approach was used to elicit WTP. Before answering the purchase question, respondents were randomly assigned to one of three different information scenarios: basic definition, impact on sustainability and the environment, and information including both environmental and social implications.

Results indicated that consumers were generally willing to pay additional amount for fair trade coffee. Information played an important role in determining what types of consumers were responsive to fair trade coffee. Furthermore, the amount of information provided and consumer WTP did not follow a linear relationship.

Results obtained in this study are useful for coffee marketers to better target their promotion strategies.

In contrast to China's fast growing coffee market, little is known about consumer preferences and far less on fair trade coffee. This study is the first of its kind to understand Chinese consumers’ preferences for coffee in general and for fair trade coffee in specific.

This study aims to probe into the effect of tourists’ novelty-seeking on situation involvement and satisfaction for the Yanshuei Fireworks Festival in Taiwan.

This study investigated 302 tourists participating in the Fireworks Festival and constructed causal relations among variables by structural equation modeling.

The results suggested that when tourists’ novelty-seeking in fireworks festival is stronger, their situation involvement in the activity will be immediately enhanced. When fireworks festival participants’ situation involvement is higher, their satisfaction is also higher. Situation involvement has a complete mediating effect between novelty-seeking and satisfaction.

Because the fireworks festival only lasts for 48 hours, and the subjects must be tourists who have just experienced fireworks, it can only adopt convenience sampling instead of random sampling. However, to avoid homogeneity, in each group, this study only selected one person for the questionnaire survey.

First, they should enhance the designed activities to create novelty; for instance, design the instruction and practice of the manufacturing of fireworks. By explanation, they enhance tourists’ learning about the display of fireworks and folk religion to satisfy participants with different degrees of novelty-seeking. Second, they can enhance the construction of situations for playfulness. For instance, upon the condition of security, the units can allow tourists to arrange fireworks independently or by group to have more fun. In addition, every year, they can display fireworks according to the Chinese Zodiac symbols to satisfy tourists’ desire of novelty-seeking and enhance their satisfaction.

From the perspective of theoretical development, this study explores and validates the mediating effects of tourists’ situation involvement in festivals between novelty-seeking and satisfaction to fill the gap of previous research.

It is possible with classical path planning algorithms to plan a path in a static environment if the instant position of the vehicle is known and the target and obstacle positions are constant. In a dynamic case, these methods used for the static environment are insufficient. The purpose of this study is to find a new method that can provide a solution to the four-rotor unmanned aerial vehicle (UAV) path planning problem in static and dynamic environments.

As a solution to the problem within the scope of this study, there is a new hybrid method in which the global A* algorithm and local the VFH+ algorithm are combined.

The performance of the designed algorithm was tested in different environments using the Gazebo model of a real quadrotor and the robot operating system (ROS), which is the widely used platform for robotic applications. Navigation stacks developed for mobile robots on the ROS platform were also used for the UAV, and performance benchmarks were carried out. From the proposed hybrid algorithm, remarkable results were obtained in terms of both planning and implementation time compared to ROS navigation stacks.

This study proposes a new hybrid approach to the path planning problem for UAVs operating in both static and dynamic environments.

An enterprise social network (ESN) is part of the landscape of information reform by enterprises, using Web 2.0. In terms of the marketing targets of typical Web 2.0 techniques, enterprise knowledge sharing in Web 2.0 can be classified into different types (individual interaction type, group interaction type, social interaction type, real‐time interaction type and delay interaction type). The purpose of this paper is to summarize the features and modes of different enterprises' knowledge sharing and study enterprise knowledge sharing quantitatively from an ESN perspective by selecting real‐time interaction type as the case.

Because of the area of research, the authors supplemented social network analysis (SNA) with a mathematical modeling method and additional in‐depth interviews.

The Web 2.0 era provides the opportunity to quantify knowledge sharing. Also, SNA can quantitatively and visually diagnose the knowledge sharing status of the enterprise and guide the enterprise's knowledge‐sharing process.

Only a case study regarding real‐time interaction type is presented; other types of interaction are not studied empirically.

SNA, combined with a mathematical modeling method and additional in‐depth interviews with team leaders or key managers in organizations, can diagnose quantitatively, visually and comprehensively the knowledge‐sharing status of the enterprise.

This paper systematically summarizes the features and modes of Web 2.0 enterprise knowledge sharing, and the multiple‐method research design represents a sound approach to targeting enterprise knowledge sharing.

The purpose of this paper is to examine the different strategies implemented by a number of successful Chinese firms currently striving to build global brands in order to improve their export capabilities. A particular emphasis is put on the transfer of marketing technology for brand engineering in order to achieve this goal.

The analysis uses case study methodology to understand what many prominent Chinese exporting firms have achieved, and develops a theory about their general strategy. Five firms have been chosen: Lenovo, Haier, Cosco, Tsingtao, Geely. Aside from these five, information is also given on the branding strategy of Li Ning and Suntech Power. A great part of the information collected is coming from “desk research”, except for Haier, Lenovo and Tsingtao for which personal contacts and visits took place in 2005 and 2006.

The findings suggest that some of the most successful Chinese firms in the field of development of brand image either use some marketing tools, such as increasing their communication spending, improving quality control, emphasizing their corporate social responsibility visibility, or by seeking a partnership through mergers/acquisition with successful foreign brands. A basic global branding model has been defined as consistent with Chinese firms’ experience.

The study was limited to seven firms to be considered among the most successful Chinese businesses. It does not intend to be perceived as statistically representative. The period of observation of the effect of the strategy which was implemented was short and during a time of booming Chinese economy. It was impossible to isolate the extraneous variables linked to the economic or competitive situation, knowing that they could affect the observations on the firms that were studied.

Though the entry strategies on the Chinese market as well as inbound foreign direct investments have been the object of a great number of publications, the outbound strategies of Chinese exporting firms, as well as the impact of technology transfer, has been covered less frequently. Therefore, this paper can have value for candidates for the improvement of global branding.