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MoS2 nanosheets with different sizes were prepared by ultrasonic liquid phase stripping and used as additives in lithium grease. The morphology, composition and structure of MoS2 nanosheets were characterized by electron microscopy, Raman spectroscopy, X-ray diffractometer and thermogravimetric analyzer; the tribological properties of lithium MoS2 grease were investigated by using four-ball friction and wear testing machine. The wear surface morphology of steel ball under MoS2 grease lubrication was analyzed by scanning electron microscopy and X-ray photoelectron spectroscopy, and the lubrication mechanism of MoS2 grease was preliminarily explored. The results show that MoS2 nanosheets show excellent wear resistance and friction reduction performance. When the diameter of the added sheet is 80 nm and the amount is 1.0%(mass fraction), the tribological performance of lithium grease is the best, the maximum no-bite load and sintering load are increased by 55.4% and 61.2% respectively compared with the base grease, and the friction coefficient is decreased by 23.15%. The maximum diameter of wear scar diameter is decreased by 21.13%.The improvement of its tribological properties is mainly related to the tribological protective film composed of various oxides of Fe, FeOOH, MoS2 and related organic matter.

The flexspline (FS) of the harmonic drive (HD) is subjected to thermal load and force load during operation, leading to the deformation difference between the inner and outer surfaces of the FS. As a result, the transmission performance of the HD assembly decreases. To overcome this problem, the thermal–mechanical coupling deformation mechanism of the FS is analyzed, and then the influence of the deformation difference on the transmission accuracy of the HD is studied in this article. On this basis, the structural parameters of the wave generator are optimized to eliminate actual backlash and to improve the actual transmission accuracy. Finally, the effectiveness of the calculation method proposed in this article was proved by the prototype test.

[Objectives] At present, the power management systems of ships require highly reliable Ethernet, and Ethernet communication cannot be interrupted when the system encounters a fault. [Methods] This paper introduces the working principle of the dual-redundant Ethernet system, and the processor ARM and the Ethernet control chip W5200 are used for the dual redundant Ethernet communication system. [Results] When the network fails or the line is damaged, the dual redundant Ethernet communication system can automatically reconnect so as to ensure that the communication system is healthy, safe and continuous. [Conclusions] The redundant communication system is verified by ship prototype with high application and promotion value.

Understanding and implementing a global perspective of business and education is a requisite skill for 21st Century educational leaders. Among principal preparation programs within the United States, there has been limited evidence of embedding the thread of global literacy or aligning curriculum with global-local skills. The purpose of this paper is to address this challenge by sharing an innovative approach that was designed and delivered in the MBA in Education Leadership program at the University of Indianapolis. This interdisciplinary initiative highlighted a thread of global perspective and aligned the thread with course content. In addition to a discussion of how instructors used various teaching methods (including lecture, discussion, hands-on activities) to promote understanding of global literacy and the assessment of student learning, this paper describes candidates' feedback regarding their positive learning experiences.

This article describes four different mechanisms for preparing teacher candidates from a liberal arts institution to teach in project based learning (PBL) classrooms: Observe it, Experience it, Create it, and Become it. For each of the four mechanisms, the authors also provide concrete examples of candidates' PBL experiences and candidates' feedback about the process. From observation to mini-teaches in schools to field placements, the authors suggest a variety of methods for engaging both undergraduate and graduate students in learning about PBL instruction. The four-step mechanism could also provide suggestions for how to implement PBL in similar liberal arts institutions.

This article examines one major research journal from China and one from the United States. The study compares the two journals with regard to three questions: 1) Who is doing research published in the journals? 2) What are the major issues and concerns represented in the journals? 3) What research methodologies are favoured in the journals? The authors believe that understanding another country's educational research practices, through addressing these questions, can better enable domestic researchers, educators and policymakers to acknowledge the major educational concerns and issues that exist across countries. As boundaries between national borders continue to blur, this understanding can help educational researchers better interpret and present their findings with greater international relevance. (Contains 11 tables and 6 notes.)

For the past two decades, China's economy has grown rapidly, averaging an astonishing 9 percent every year. One result of this growth has been the demand for more and better educational opportunities at the postsecondary level. In response, the Chinese government, which holds a tight control over its highly centralized education system, introduced a number of drastic measures to expand access to postsecondary education, including the formation of "Internet Colleges"--or "wangluo xueyuan," in Chinese. These colleges, which are units within existing universities, are dedicated to offering postsecondary-level educational programs online. Other than the China Central Radio and TV University (CCRTVU), they are the only institutions approved by the government to offer online postsecondary education. The Internet College initiative was a bold experiment for the Chinese education system, and as such, it has gone through a number of changes and modifications since its inception. These changes and modifications partly reflect the government's struggle to strike a balance between tight regulation and flexibility, between tradition and innovation, and partly reveal the current social, political, economical, and educational realities in China with regard to online education. In this article, the authors examine the short evolutionary path of Internet Colleges in China to provide a glimpse into the larger aspects of online higher education in China. (Contains 1 table and 9 notes.)

This paper considers the case of the Michigan Migrant Head Start program to describe and analyze the labor market conditions and teaching staff characteristics to identify the challenges faced by Migrant Head Start grantees in attracting, hiring, retaining, and training degreed teachers. The emphasis is on describing and analyzing the child care labor market characteristics that confront Migrant Head Start grantees in upstream locations and on describing the characteristics and opinions of Migrant Head Start teachers and interpreting their significance for developing educational programs that facilitate the ability of Migrant Head Start teachers to become degreed in early childhood education. The implications of the findings for making early childhood education work for Migrant Head Start teachers are discussed from the perspective of administrators of Migrant Head Start programs and teacher preparation programs at community colleges and universities. (Contains 1 table.)