Hybrid heuristic and mathematical programming in oil pipelines networks： Use of immigrants

We solve the problem of petroleum products distribution through oil pipelines networks. This problem is modelled and solved using two techniques: A heuristic method like a multiobjective evolutionary algorithm and Mathematical Programming. In the multiobjective evolutionary algorithm, several objective functions are defined to express the goals of the solutions as well as the preferences among them. Some constraints are included as hard objective functions and some are evaluated through a …     

Teamwork and Entrepreneurial Behavior among K-12 Teachers in the United States

Abstract

This study attempted to identify the predictors of entrepreneurial behavior by assessing a series of variables that included teamwork skills and demographic variables, and to explore teachers’ experiences with teamwork. A sample of 367?K-12 public school teachers completed the survey. The findings indicated that teamwork predicts entrepreneurial behavior. Most participants received teamwork training through their school districts. Barriers to teamwork included time constraints, individual differences, and inability to collaborate.     

Comparing demand functions when different price manipulations are used: Does unit price help?

Six hens pecked a key (Experiment 1) or pushed a door (Experiment 2) to obtain food reinforcement. In both experiments and as an analogue of price changes, the response requirements were varied in two ways: by increasing the number of responses required and by increasing the required force of each response. The two price manipulations (response number and response force) had different effects on behavior and produced different-shaped demand functions when the rates of consumption were plotted logarithmically against the price analogues. Irrespective of response topography, when the number of required responses was varied, the data paths appeared linear, with slopes close to −1.0. When the required force of each keypeck and doorpush was varied, the data paths were clearly curved, with increasingly steep downward slopes as the force increased. Using the concept ofunit price did not fully remove the different effects of the two price manipulations. Those differences are best attributed to the differing times needed in order to complete each response unit under those price manipulations.     

A novel 3-stage structure for a low-noise,high-gain and gain-flattened L-band erbium doped fiber amplifier

The configuration of the novel three-stage L-band erbium-doped fiber amplifier with very large and flat gain and very low noise figure presented in this paper uses the forward ASE (amplified spontaneous emission) from the first section of the EDF (erbium-doped fiber) and the backward AS E from the third section of the EDF (both serve as the secondary pump sources of energy) to pump the second EDF. To improve the pump efficiency, the power of the pump is split into two parts(with a ratio of e.g. 2:7). The characteristics of this L-band EDFA are studied on the basis of the Giles Model with ASE.     

The work of Ambroise Tardieu: the first definitive description of child abuse

The first important monograph describing the battered child syndrome was written in 1860 by Ambroise Tardieu, a French forensic physician. Here is a translation of his article, published in the Annales d'hygiene publique et de medecine legale, with the title "Etude medico-legale sur les sevices et mauvais traitements exerces sur des enfants." The first part of his article is entirely translated. A brief summary of the 32 cases report described by Tardieu in the second part of his article is presented.     

Should I use co-assessment in higher education? Pros and cons from teachers and students’ perspectives

Co-assessment is a type of participatory assessment in which the teacher and student jointly discuss, negotiate and assess the student’s task or performance. Although the literature on co-assessment is scarce, some authors highlight the benefits for students of participating in co-assessment in higher education, including learning, improved communication, and greater assessment literacy. This study has a double objective: on the one hand, to analyse the strengths and limitations perceived by students participating in co-assessment practices; on the other hand, to explore the strengths, weaknesses, opportunities and threats perceived by professors participating in the experience. The study was developed in 8 class groups with the participation of 470 students and 4 teachers. The qualitative analysis of the data obtained from the questionnaires and focus groups indicates that the students acknowledged several strengths, among which learning from mistakes was prominent. Students also noted some limitations, particularly the lack of adjusted scoring. Professors offered another perspective that complemented the vision of their students, noting that co-assessment presents opportunities as well as risks that may jeopardise its implementation.     

“Shut up and calculate”: the available discursive positions in quantum physics courses

Educating new generations of physicists is often seen as a matter of attracting good students, teaching them physics and making sure that they stay at the university. Sometimes, questions are also raised about what could be done to increase diversity in recruitment. Using a discursive perspective, in this study of three introductory quantum physics courses at two Swedish universities, we instead ask what it means to become a physicist, and whether certain ways of becoming a physicist and doing physics is privileged in this process. Asking the question of what discursive positions are made accessible to students, we use observations of lectures and problem solving sessions together with interviews with students to characterize the discourse in the courses. Many students seem to have high expectations for the quantum physics course and generally express that they appreciate the course more than other courses. Nevertheless, our analysis shows that the ways of being a “good quantum physics student” are limited by the dominating focus on calculating quantum physics in the courses. We argue that this could have negative consequences both for the education of future physicists and the discipline of physics itself, in that it may reproduce an instrumental “shut up and calculate”-culture of physics, as well as an elitist physics education. Additionally, many students who take the courses are not future physicists, and the limitation of discursive positions may also affect these students significantly.     

Feeling Brown in the Academy: Decolonizing Mentoring Through a Disidentification Muxerista Approach

According to the Chronicle of Higher Education, “Hispanics” comprise only 4% of the full-time faculty in U.S. universities, although Latin@s comprise 16.4% of the U.S. population. Given the under-representation of Latin@ faculty, efforts to support and retain them are paramount. Recently a small body of literature has surfaced explicitly centering the practices of peer mentoring among Latin@s. Through collaborative auto-ethnography and counter-storytelling, using a framework of disidentification, muxerista mentoring, and community cultural wealth, we add to this literature by discussing our experience of engaging in non-hierarchical Latina peer mentoring at a predominantly White university. The main themes include: merging emotional needs with professional growth, forging learning and research partnerships, Browning teaching spaces and transforming institutional practices.     

Automatically extracting sheet-metal features from solid model

With the development of modern industry,sheet-metal parts in mass production have been widely applied in mechanical,communication,electronics,and light industries in recent decades; but the advances in sheet-metal part design and manufacturing remain too slow compared with the increasing importance of sheet-metal parts in modern industry. This paper proposes a method for automatically extracting features from an arbitrary solid model of sheet-metal parts; whose characteristics are used for classification and graph-based representation of the sheet-metal features to extract the features embodied in a sheet-metal part. The extracting feature process can be divided for valid checking of the model geometry,feature matching,and feature relationship. Since the extracted features include abundant geometry and engineering information,they will be effective for downstream application such as feature rebuilding and stamping process planning.