PhD students presenting, staging and announcing their educational status - An analysis of shared images in social media
ارائه، حضور در صحنه و اعلان وضعیت آموزشی به دانشجویان دکترا - یک تحلیل روی تصاویر به اشتراک گذاشته شده در رسانه های اجتماعی-2018
Little research has been conducted on the question of academics use of social media. The effects of social media on the educational environment of postgraduate students need to be further explored. The purpose of this study was to investigate the underlying values and ideas of being in postgraduate education by analysing 176 posted photos on social media. The findings show that PhD students manifest their educational status by presenting themselves as being in a process, staging academic artefacts and announcing important achievements towards the goal of earning their degree. These activities represent a global understanding of being a PhD student, that exists regardless of nation, gender or ethnicity and as such represents a “meta curricula” that exists above and beyond any locally defined PhD syllabus. It should be considered that the constant mirroring of PhD student life that has been made possible via social platforms seems to gain in importance and that the enculturation into the academic culture that exists among postgraduate students own activities on social media needs to be taken into account when addressing postgraduate education, in practice as well as in research.
Low-carbon product selection with carbon tax and competition: Effects of the power structure
انتخاب محصول کم کربن با مالیات کربن و رقابت: تاثیرات ساختار توانی-2018
This paper considers product selection strategies of two competitive firms in the presence of carbon tax. Optimal strategies are developed for product selection of the firm with two game structures, namely, the Nash game and the Stackelberg game, by which the paper conducts an analytical examination of the effect of power structure on the product selection strategy of the firm over various levels of carbon tax rate. The critical managerial findings derived with the studies are as follows: (i) Two competitive firms will always adopt the same product strategy with the Nash pricing game, regardless of the carbon tax rate, which is in contrast to that they will adopt a differentiated product strategy over the low carbon tax rates with the Stackelberg pricing game. (ii) Two competitive firms will both select the common or low-carbon product with randomness over the middle carbon tax rates with the Nash product selection game, which is contrast to that the randomness in their product selections is removed with the Stackelberg product selection game, which leads to an existence of the pure strategy Stackelberg equilibrium for their product selection strategies over the middle carbon tax rates. The inherent mechanisms leading to these essential differences are also discussed in the paper.
keywords: Low-carbon product |Power structure |Carbon emission |Carbon tax |Competition
A Novel behavioral scoring model for estimating probability of default over time in peer-to-peer lending
یک مدل امتیازدهی رفتاری نوین برای تخمین احتمال شکست درطی زمان در وام دهی همکار به همکار-2018
Traditional behavioral scoring models applying classification methods that yield a static probability of default may ignore the borrowers’ dynamic characteristics because borrower repayment behavior evolves dynamically. In this study, we propose a novel behavioral scoring model based on a mixture survival analysis framework to predict the dynamic probability of default over time in peer-to-peer (P2P) lending. A random forest is utilized to identify whether a borrower will default, and a random survival forest is introduced to model the time to default. The results of an empirical analysis on a Chinese P2P loan dataset show that the proposed ensemble mixture random forest (EMRF) has a better performance in terms of predicting the monthly dynamic probability of default, while compared with standard mixture cure model, Cox proportional hazards model and logistic regression. It is also concluded that the proposed EMRF model provides a meaningful output for timely post-loan risk management.
keywords: Behavioral scoring |Dynamic probability |P2P lending |Random forest |Random survival forest |Risk management |Survival analysis
Coupled queues with customer impatience
صف های جفت با بی صبری مشتری-2018
Motivated by assembly processes, we consider a Markovian queueing system with multiple coupled queues and customer impatience. Coupling means that departures from all constituent queues are synchronised and that service is interrupted whenever any of the queues is empty and only resumes when all queues are non-empty again. Even under Markovian assumptions, the state–space grows exponentially with the number of queues involved. To cope with this inherent state–space explosion problem, we investigate performance by means of two numerical approximation techniques based on series expansions, as well as by deriving the fluid limit. In addition, we provide closed-form expressions for the first terms in the series expansion of the mean queue content for the symmetric coupled queueing system. By an extensive set of numerical experiments, we show that the approximation methods complement each other, each one being accurate in a particular subset of the parameter space.
keywords: Kitting process |Queues with customer impatience |Regular perturbation |Fluid limit
Does money matter? The effects of block grants on education attainment in rural China: Evidence from intercensal population survey 2015
آیا پول مهم است؟ تاثیرات بورسیه های بلوکی روی موفقیت آموزشی در روستاهای چین: شواهدی از جمعیت بین دوسرشماری سال 2015-2018
Considerable disagreement exists on the impacts of intergovernmental transfers in improving education access and outcomes. This is further complicated by the fungibility of these transfers, especially in a developing country setting. This study examines the effects of the block grant established by the Chinese government to subsidize the operating costs of rural compulsory education in 2006 on education attainment in a difference-in-difference framework. Comparing students whose compulsory schooling was completed just before or after the reform in counties receiving higher and lower percentages of their operating costs from higher-level governments, we find that a 20% increase in subsidies received from higher levels of government has led to 0.21 more years of schooling completed (0.07 standard deviation) and a 2.2 percentage points rise in the probability of completing compulsory education (0.08 standard deviation). These findings have implications not just for China but also for other developing countries which aim to achieve universal compulsory education.
keywords: Education finance |Education attainment |Education policy |Block grant |China
Optimizing make-to-stock policies through a robust lot-sizing model
بهینه سازی سیاست های ساخت برای سهام ازطریق یک مدل اندازه گذاری بزرگ محکم-2018
In this paper we consider a practical lot-sizing problem faced by an industrial company. The company plans the production for a set of products following a Make-To-Order policy. When the productive capacity is not fully used, the remaining capacity is devoted to the production of those products whose orders are typically quite below the established minimum production level. For these products the company follows a Make-To-Stock (MTS) policy since part of the production is to fulfill future estimated orders. This yields a particular lot-sizing problem aiming to decide which products should be produced and the corresponding batch sizes. These lot-sizing problems typically face uncertain demands, which we address here through the lens of robust optimization. First we provide a mixed integer formulation assuming the future demands are deterministic and we tighten the model with valid inequalities. Then, in order to account for uncertainty of the demands, we propose a robust approach where demands are assumed to belong to given intervals and the number of deviations to the nominal estimated value is limited. As the number of products can be large and some instances may not be solved to optimality, we propose two heuristics. Computational tests are conducted on a set of instances generated from real data provided by our industrial partner. The heuristics proposed are fast and provide good quality solutions for the tested instances. Moreover, since they are based on the mathematical model and use simple strategies to reduce the instances size, these heuristics could be extended to solve other multi-item lot-sizing problems where demands are uncertain.
keywords: Lot-sizing |Make-To-Stock |Robust optimization |Mixed-integer linear programming
Swapping inventory between competing firms
مبادله موجودی بین شرکتهای درحال رقابت-2018
In this study, we investigate how competing firms swap inventory. We consider two firms located in two different markets that produce the same type of product. Each firm sells in the two markets. The selling price in each market is determined by the selling quantities of the two firms. We first show that the optimal swapping quantity is zero when firms decide to swap inventory without a sophisticated method. That is, they would not swap inventory. However, under our proposed inventory swapping method, competing firms swap a positive amount of inventory, enabling a higher profit for both firms. We also find that the swapped quantity increases as transportation costs decrease, and swapping inventory may not be beneficial if the transportation cost is either too low or too high. In addition, we investigate how to implement the swapping inventory agreement when the value of the swapped inventory differs by market. We show that firms may prefer to return the physical products to pay the value difference, especially if they are risk-averse.
keywords: Inventory swapping |Competition |Cooperation
Business Process Management Alignment
ترازبندی مدیریت فرآیند تجاری-2015
Alignment is a concept that dates back to the late 1990s, when it was described by Paul Strassmann 1 : “Alignment is the capacity to demonstrate a positive relationship between information technologies and the accepted financial measures of performance.” Alignment of business process management (BPM) hence should follow a similar principle or pattern to be effective. The objective therefore is how this alignment to and between BPM can create value that is ultimately measurable as a favorable financial outcome for a commercial enterprise. Business process management alignment, which is focused on both reusability and accelerating automation, requires that business managers have an understanding of what alignment is, how to develop an alignment competency, and what considerations should be made by organizations to ensure alignment is adequately adopted. This chapter discusses these aspects of alignment and gives credence to the development of aligned BPM.
Business Architecture Management
معماری مدیریت کسب و کار-2015
The act of undertaking enterprise architecture has much in common with wine tasting. The critics of enterprise architecture would probably say: “I agree; both activities are expensive, overly analytical, and the participants get caught up in long-winded debates about definitions and subtleties that most people don’t care about!” As you can imagine, this is not my opinion and definitely not the point I’m trying to make here. Rather, the commonalties I see between both activities are that they mean different things to different people, that they are concerned with collective meaning-making, and that they are deeply social in nature. Deciding if a wine is good is greatly determined by personal preferences. Don’t get me wrong, wine connoisseurs may reach a consensus and affirm that a certain wine is well balanced. However, such a consensus says neither very much about the personal preferences of each wine connoisseur nor what wine they would enjoy during a supper with close friends. Similarly, the literature on enterprise architecture offers a large range of definitions and perspectives on the meaning of the term “enterprise architecture” as well as what constitutes its adequate (good) practice. Despite this lack of unanimous agreement, a pragmatic practitioner will notice, in general, that there is agreement that enterprise architecture is about helping enterprises to be more effective and that it is important to understand both the business and technical aspects in order to reach this goal. Like wine tasting, enterprise architecture is about getting together with other people and trying to make sense of our experiences, our reality. Whereas wine tasting is concerned with the sensorial experiences procured by wine consuming, enterprise architecture is concerned with the realities of working and evolving in an enterprise. Moreover, both activities are very social in nature in that both activities require and unfold in the context of people interacting together. I have been an enterprise architecture practitioner and scholar for a number of years now. I have participated in enterprise architecture-related activities that have been recognized by MIT, Gartner, and Forrester. Through these activities, like many readers of this book, I have often experienced the challenges of doing enterprise architecture and trying to help enterprises be more effective. Often, the v literature had little to offer me on how to actually do the work and have effective meaning-making discussions with fellow workers about the enterprise we shared. This was especially true when discussing the nontechnical aspects of the enterprise. In the field, in my experience, the term “business architecture” is steadily establishing itself as the de facto term when referring to the concerns of making sense and evolving the business aspects of an enterprise. Sadly, in my opinion, despite its importance, it is still very underdeveloped and fragmented. A great deal of the available material overly focuses on modeling and refers very little to the wealth of knowledge that exists on the subjects of enterprises, organizations, and their design: knowledge that lies in the fields of management, sociology, psychology, and many others. The value of this book lies in the fact that the authors are contributing to the development of business architecture and its practices in a way that is useful for practitioners and academics and also makes use of existing knowledge provided by important organizational scholars such as Demings, Argyris, Schein, Porter, Ansoff, Martin, Kaplan, Norton, Mintzberg, Drucker, and Friedman. As stated by Schopenhauer: “Thus the task is not so much to see what no one yet has seen, but to think what nobody yet has thought about that which everybody sees.” Accordingly, this book offers a refreshing way to think about business architecture in the context of enterprise architecture. This book is one of very few that provides a business-oriented perspective on b
Semantic-based knowledge categorization and organization for product design enterprises
دسته بندی و سازماندهی دانش مبتنی بر معنا برای تولید محصولات تجاری-2015
Former knowledge engineering research aimed at boosting automatic reasoning. However recent knowledge management research focused on promoting the knowledge sharing and reusing among the people. Because of the different aims between the two directions, former knowledge representation schemata, such as rule based representation, frame from knowledge engineering research does not fit to the current knowledge management scenarios. In this paper, for the purpose of building knowledge management systems for product design enterprises, knowledge items are classified into seven types based on the semantics of their usage. Then their representations are discussed respectively. Based on the above classification, a knowledge representation meta-model and a basic domain ontology reference model for cooperative knowledge management systems are put forward. The reference model is an abstraction that can be reused and extended in knowledge management systems of different enterprises. Finally, the patterns of knowledge acquisition processes in cooperative knowledge management scenarios of product design processes are studied. Key words: knowledge management, product design process, knowledge categorization