A Comparison of Teacher-directed Versus Self-directed Learning Preferences of Students at Five Selected Community Colleges: Exploring the Relationships Among Age, Gender, and Academic Majors

One of the major priorities for community colleges is to focus on the pedagogical tools that will allow students to achieve excellence and quality in curriculum and instruction to meet the changing societal needs (Shearon & Tollefson, 1989). Rapid demographic, social, and technological changes demand that community colleges produce self-directed lifelong learners (Closson, 1996). The study of student learning preferences for more teacher-directed or more self-directed learning is one of the concepts that is important in enhancing teaching and learning practices. The purpose of this study was to examine students\u27 teacher-directed versus self-directed learning preferences in specific courses. The possible relationships among age, gender, and academic majors and the learning preferences (teacher-directed or self-directed) were also explored. The revised version of Learning Style Preference Questionnaire (LSPQ) originally designed by Hinkle (1990) was administered to 563 students at five selected community colleges in the southeast. The majority of the participants were female traditional students majoring in the natural sciences. The sample showed a preference for teacher-directed orientation in specific courses. Statistically significant differences were observed in the magnitude of the teacher-directed orientation between the mean scores of male and female students with male students scoring significantly higher than the female students. Traditional students obtained significantly higher mean scores on the items addressing the delivery of instruction than the nontraditional students. Nontraditional students obtained significantly higher mean scores on the items addressing the testing of learning. Gender had an impact on the magnitude of the teacher-directed learning preferences for evaluation and testing of learning. Academic majors had an impact on the magnitude of the teacher-directed learning preferences for evaluation of learning. Students in this study preferred a teacher-directed approach to learning. Follow-up research using a variety of instruments may investigate how this preference contributes to or affects academic achievement. It is recommended that the methods and procedures adopted in this study be replicated in other community colleges across the nation. Learning preference concepts and methods should be developed at the community college level to include professional development of instructors so that they may better provide learning opportunities for their students. Such studies may also be conducted in other parts of the world to determine how cultural differences may impact on learning preferences

An adaptation of Pissarides (1990) by using random job destruction rate

This paper works on an adaptation of the standard Pissarides model to incorporate-rate an exponentially distributed match specific�c job destruction rate. We discuss the characterization of equilibrium, equilibrium wage, number of equilibria, stead state unemployment, welfare and comparative statics problems in this adapted model

Waste cooking oil as an energy resource: review of Chinese policies

Converting waste cooking oil into biofuel represents a three-win solution, dealing simultaneously with food security, pollution, and energy security. In this paper, we encode the policy documents of waste cooking oil refining biofuel in China based on content analysis, and explore the related policies from the two dimensions as basic policy tools and enterprises supply chain. Research indicates the weak institution coordination of policy issuing entities. Also, the findings show that tools of regulatory control and goal planning are overused. Policies of government procurement, outsourcing and biofuel consumption are relatively scarce. Generally, government focuses more on formulating policies from the strategic, administrative and regulatory aspects, while less on market-oriented initiatives as funding input and financial support

An adaptation of Pissarides (1990) by using random job destruction rate

This paper works on an adaptation of the standard Pissarides model to incorporate-rate an exponentially distributed match specific�c job destruction rate. We discuss the characterization of equilibrium, equilibrium wage, number of equilibria, stead state unemployment, welfare and comparative statics problems in this adapted model

Relationship between Microstructure and Properties of Cu-Cr-Ag-(Ce) Alloy Using Microscopic Investigation

Microstructure, precipitation hardening response, and mechanical and physical properties of Cu-Cr-Ag alloy and Cu-Cr-Ag-Ce alloy have been investigated using transmission electron microscopy, scanning electron microscope, optical microscope, electrical conductivity analysis, and tensile test. The influence of element Ce on the matrix refinement, impurity removal, and precipitation in the Cu-Cr-Ag alloys has been analyzed. The experimental results show that the strength and electrical conductivity of Ce containing alloys are greater than those of Ce-free alloys after each processing step. Improvement of strength and electrical conductivity of the Cu-Cr-Ag alloy by adding Ce element is attributed to removing oxygen and sulfur from as-cast alloy

Modelling floppy iris syndrome and the impact of phenylephrine on iris buckling

Abnormal iris movement (floppy iris syndrome) during intraocular surgery is associated with an increased risk of intraoperative complications. We have previously investigated this scenario with respect to intracameral air in corneal endothelial transplantation, and described the concept of iris buckling. As a number of clinical interventions are recommended for addressing floppy iris syndrome, we wished to evaluate the impact of intracameral phenylephrine on iris buckling and so refine our mathematical model. We considered the stability of an iris structure under a uniform pressure loading. We performed mathematical and computational simulations to demonstrate iris buckling, and then altered the parameters to assess the impact of phenylephrine on the model. We elucidated a number of buckled iris configurations which become unstable as the intraocular pressure increased, for transversely isotropic iris material properties, and identified a positive correlation between the critical pressure and the iris stiffness. A mechanical analysis with a dilated pupil (mimicking phenylephrine use) was also conducted, and demonstrated a significant increase in the critical pressure required to induce iris buckling. We have shown that iris buckling can arise at lower pressures when the iris stiffness is reduced, as in floppy iris syndrome. The use of phenylephrine was shown to prevent iris movement (buckling) by increasing the required critical pressures. This refined model demonstrates the positive effectiveness of phenylephrine in the management of floppy iris syndrome and gives evidence to the clinical practice of using this as a preventative measure

Tree-ring-based precipitation reconstruction in the source region of Weihe River, northwest China since AD 1810

A tree-ring width chronology of Picea purpurea Mast from Mt. Shouyang in the source region of Weihe River (SWR), northwest China, was developed in this study. Correlation analysis showed that the precipitation from previous August to current July was the limiting climate factor of tree growth. Using a reliable and stable linear regression model, which explained 42.6% of the variance of the actual precipitation during the calibration period from 1958 to 2014, a 205-year long precipitation series was reconstructed for the SWR. The dry years in the reconstruction were well supported by historical documents, and famous historical droughts were also recorded in the dry periods of a low-frequency scale of the reconstructed precipitation. As demonstrated by the spatial correlation patterns, the reconstructed series compared well with other hydroclimate records for northwest China, indicating that it could represent large-scale hydroclimate changes. The 2-8-year interannual cycles and the interdecadal quasiperiods of 15.9 years and 18.6 years revealed that the precipitation in this region was probably affected by the El Nino-Southern Oscillation and North Atlantic Oscillation. The dry/wet years corresponded well with the El Nino/La Nina events and the SWR commonly experienced droughts during the low periods of North Atlantic Oscillation

Sunshine duration reconstruction in the southeastern Tibetan Plateau based on tree-ring width and its relationship to volcanic eruptions

Sunshine is as essential as temperature and precipitation for tree growth, but sunshine duration reconstructions based on tree rings have not yet been conducted in China. In this study, we presented a 497-year sunshine duration reconstruction for the southeastern Tibetan Plateau using a width chronology of Abies forrestii from the central Hengduan Mountains. The reconstruction accounted for 53.5% of the variance in the observed sunshine during the period of 1961-2013 based on a stable and reliable linear regression. This reconstructed sunshine duration contained six sunny periods (1630-1656, 1665-1697, 1731-1781, 1793-1836, 1862-1895 and 1910-1992) and seven cloudy periods (1522-1629, 1657-1664, 1698-1730, 1782-1792, 1837-1861, 1896-1909 and 1993-2008) at a low-frequency scale. There was an increasing trend from the 16th century to the late 18th and early 19th centuries and a decreasing trend from the mid-19th to the early 21st centuries. Sunshine displayed inverse patterns to the local Palmer drought severity index on a multidecadal scale, indicating that this region likely experienced droughts under more sunshine conditions. The decrease in sunshine particularly in recent decades was mainly due to increasing atmospheric anthropogenic aerosols. In terms of the interannual variations in sunshine, weak sunshine years matched well with years of major volcanic eruptions. The significant cycles of the 2- to 7-year, 20.0-year and 35.2-year durations as well as the 60.2-year and 78.7-year durations related to the El-Nino Southern Oscillation, the Pacific Decadal Oscillation and the Atlantic Multidecadal Oscillation suggested that the variation in sunshine duration in the southeastern Tibetan Plateau was possibly affected by large-scale ocean-atmosphere circulations. (C) 2018 Elsevier B.V. All rights reserved