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The production dice game is a powerful learning exercise focusing on the impact of variability and dependency on throughput and work‐in‐process inventory of flow lines. This paper seeks to extend the basic dice game along the following lines. First, it will allow operations to take place concurrently as opposed to sequentially, which works better in a classroom setting. Second, it will allow both starvation and blocking of the line. Third, it will consider balanced lines with workstations characterized by different degrees of variability. Finally, it aims to use different sets of dice in order to represent a wide range of variation coefficients of the production line. The obtained insights can be extended to a supply chain context as well. The developed game can be played on‐line and the software is freely downloadable.

The paper extends the dice game and offers an easy‐to‐use simulation tool.

The key aspect of students' learning experience is the understanding of the relationship between variability and throughput in an environment with dependent workstations and limited buffers.

A rather complicated research question is transformed into an easy‐to‐use simulation tool that in no time can be used by practitioners and students.

The purpose of this paper is to extend the role of the theory of constraints (TOC) to complement, reinforce, and help integrate conventional operations management (OM) concepts by using an Excel‐based version of the dice game discussed in The Goal by Goldratt.

The paper discusses the motivation for and the development and evaluation of an Excel‐based dice game model of a production system for novice managers to experiment with. A set of experiments related to OM concepts (e.g. inventory, capacity, and variability) is designed and counterintuitive results are discussed. The paper concludes by demonstrating how TOC provides an integrative OM framework.

The novel The Goal by Goldratt serves as a comprehensive case study in OM. The computerized dice game provides a mechanism for understanding relationships among various OM concepts. The proposed set of experiments strengthens the linkages between OM and TOC concepts. Managers can conduct additional experiments and predict/interpret the results without spending time in the logistics of setting up the manual dice game repeatedly.

The proposed dice game simulates a fairly simple serial production system so the generalization of results obtained might not be intuitively convincing for more complex production systems. More advanced OM concepts such as push (MRP) and pull (JIT) systems can easily be investigated using the underling logic of the dice game proposed here.

The model provides an innovative way to integrate TOC concepts with mainstream OM concepts and thereby, renews interest in OM.

Several versions of dice games, both manual and spreadsheet based, have appeared in the literature, however, none attempt to address as wide a variety of operations issues as the game proposed here.

Si-based micro electro mechanical systems (MEMS) magnetometer does not require specialized magnetic materials avoiding magnetic hysteresis, ease in fabrication and low power consumption. It can be fabricated using the same processes used for gyroscope and accelerometer fabrication. The paper reports the dicing mechanism for the released MEMS xylophone magnetic sensor fabricated using wafer bonding technology and its characterization in ambient pressure and under vacuum conditions. The purpose of this paper is to dice the wafer bonded Si-magnetometer in a cost-effective way without the use of laser dicing and test it for Lorentz force transduction.

A xylophone bar MEMS magnetometer using Lorentz force transduction is developed. The fabricated MEMS-based xylophone bars in literature are approximately 500 µm. The present work shows the released structure (L = 592 µm) fabricated by anodic bonding technique using conducting Si as the structural layer and tested for Lorentz force transduction. The microstructures fabricated at the wafer level are released. Dicing these released structures using conventional diamond blade dicing may damage the structures and reduce the yield. To avoid the problem, positive photoresist S1813 was filled before dicing. The dicing of the wafer, filled with photoresist and later removal of photoresist post dicing, is proposed.

The devices realized are stiction free and straight. The dynamic measurements are done using laser Doppler vibrometer to verify the released structure and test its functionality for Lorentz force transduction. The magnetic field is applied using a permanent magnet and Helmholtz coil. Two sensors with quality factors 70 and 238 are tested with resonant frequency 112.38 kHz and 114.38 kHz, respectively. The sensor D2, with Q as 238, shows a mechanical sensitivity of 500 pm/Gauss and theoretical Brownian noise-limited resolution of 53 nT/vHz.

The methodology and the study will help develop Lorentz force–based MEMS magnetometers such that stiction-free structures are released using wet etch after the mechanical dicing.

The learning outcomes of this paper is as follows: understand the issues that faced private Egyptian textile producers following the January 2011 revolution and how that impacted their business model. Evaluate whether Dice’s inorganic expansion through acquiring Alex Clothing Company is a sound strategic decision given the economic uncertainty in Egypt. Analyze the acquisition decision through projection evaluation techniques, including net present value (NPV), internal rate of return (IRR) and modified IRR (MIRR), to measure whether the acquisition will add value to Dice. Discuss non-financial issues post-acquisition that are not captured by traditional capital budgeting and project evaluation techniques.

Dice Manufacturing Company, an established and successful textile manufacturing family business, is facing an important investment decision with regard to inorganic expansion through the acquisition of Alex Clothing Company and its subsidiary United Dyers. The case is intended to be discussed in an undergraduate corporate finance class. The case setting is inside Dice Manufacturing Company, where one of the founders, Nagy Toma and his CFO Victor ElMalek are analyzing the acquisition decision in January 2015. The protagonist is Victor ElMalek, who has to recommend a course of action for the company owners. The case allows students to apply capital budgeting and project valuation methods to make a decision on whether the acquisition brings value to Dice and to analyze issues management can face post-acquisition. The case follows through the history of Dice, presenting its business model and changes that accompanied the 2011 revolution. It then moves on to outline the acquisition opportunity and provides data for students to analyze through traditional project valuation techniques, including NPV, IRR and MIRR.

Undergraduate.

CSS 1: Accounting and Finance.

Teaching notes are available for educators only.

Although in principle prior information can significantly improve inference, incorporating incorrect prior information will bias the estimates of any inferential analysis. This fact deters many scientists from incorporating prior information into their inferential analyses. In the natural sciences, where experiments are more regularly conducted, and can be combined with other relevant information, prior information is often used in inferential analysis, despite it being sometimes nontrivial to specify what that information is and how to quantify that information. In the social sciences, however, prior information is often hard to come by and very hard to justify or validate. We review a number of ways to construct such information. This information emerges naturally, either from fundamental properties and characteristics of the systems studied or from logical reasoning about the problems being analyzed. Borrowing from concepts and philosophical reasoning used in the natural sciences, and within an info-metrics framework, we discuss three different, yet complimentary, approaches for constructing prior information, with an application to the social sciences.

The purpose of this paper is to analyse employees’ lying behaviour and its findings have important implication for the management and prevention strategies of lying in the workplace. Employee lying has caused both reputational and financial damage to employers, organisations and public authorities. This study adopts a psycho-cognitive perspective to examine the mechanism of lying reduction and the influence envy has on lying behaviour.

Incorporating social comparison phenomenon and cognate studies this study suggests that envy may restrain people from lying in the workplace. Specific hypotheses are developed and tested with 271 participants using dice game scenarios.

Research findings have found that people are likely to lie if lying brings them benefits. However, the findings also reveal that the envy aroused between two people may act as a psychological barrier to reduce the tendency to lie.

The research findings have provided an alternative perspective to the current prevailing view of envy as a negative emotion. Envy need not always be negative. Envy can provide an internal drive for people to work harder and enhance themselves but it can also act as a brake mechanism and self-regulator to reduce lying, and thereby has a potentially positive value.

The bonding of laser semiconductor dice for optical telecommunication systems is very difficult because of the fragility of these new components, the necessity to bond them with very high accuracy in their location, and the necessity to have a very homogeneous bond with a low thermal resistivity. A new bonding equipment has, therefore, been developed for this application: it can be used for preform, eutectic, or epoxy bonding, and naturally with many other components. Compared with other bonding equipment, such as preform or eutectic scrubbing, it presents the following advantages: the bonding is initiated and homogenised with an ultrasonic vibration of very small energy and amplitude which does not damage the laser dice; the workholder is built with a very small thermal inertia in order to prevent degradation of the bond when indium or tin alloy preforms are used; and it allows very high accuracy in the location of the dice. The results obtained with indium and epoxy bonding show that this equipment is particularly suitable for laser die bonding, and it permits the use of epoxy creams for this application in spite of their relatively low thermal conductivity.

This case captures the experience of the newly hired investigation officer (IO) at the SECP, who crafts a front running case focused on the ethical transgressions by equity trader and KATS operator, at a famous brokerage house named Mir Ali Chaudhary Securities (MAC) Securities and three traders at DICE in Pakistan. The case outlines the whole series of investigation event that took place, from the IO identifying the smoke to all the pieces of puzzle together to form collectively evidence of front running. The case outlines and probes students to think at each stage of investigation as to how to answer the general claims that insider trading should be legalized. All these questions are viewed from the perspective of Pakistan’s regulatory environment.

The authors use a descriptive case study methodology approach.

The investigation trial held Sidney and Aslam guilty, sentencing them to imprisonment and making them pay fine to the Securities Exchange Commission of Pakistan (SECP) worth Rs 5m and Rs 1m, respectively. Likewise, the three equity traders at DICE were sentenced to imprisonment and charged a fine of Rs. 1m each.

On March 21, 2018, Mr Sidney, the equity trader, Mr Aslam, a KATS operator at MAC Securities and three equity traders at DICE Securities (Pvt.) Ltd were convicted under Securities Act (2015) and Court of law. Sidney and Aslam were alleged of tipping off advance confidential information of their clients’ order to the three equity traders at DICE, whereas the three traders at DICE were alleged of trading shares based on the tipped information in their trading account before the MAC clients’ orders were filled.

A major key success factor regarding proficient Bayes threshold denoising refers to noise variance estimation. This paper focuses on assessing different noise variance estimations in three Bayes threshold models on two different characteristic brain lesions/tumor magnetic resonance imaging (MRIs).

Here, three Bayes threshold denoising models based on different noise variance estimations under the stationary wavelet transforms (SWT) domain are mainly assessed, compared to state-of-the-art non-local means (NLMs). Each of those three models, namely D1, GB and DR models, respectively, depends on the most detail wavelet subband at the first resolution level, on the entirely global detail subbands and on the detail subband in each direction/resolution. Explicit and implicit denoising performance are consecutively assessed by threshold denoising and segmentation identification results.

Implicit performance assessment points the first–second best accuracy, 0.9181 and 0.9048 Dice similarity coefficient (Dice), sequentially yielded by GB and DR; reliability is indicated by 45.66% Dice dropping of DR, compared against 53.38, 61.03 and 35.48% of D1 GB and NLMs, when increasing 0.2 to 0.9 noise level on brain lesions MRI. For brain tumor MRI under 0.2 noise level, it denotes the best accuracy of 0.9592 Dice, resulted by DR; however, 8.09% Dice dropping of DR, relative to 6.72%, 8.85 and 39.36% of D1, GB and NLMs is denoted. The lowest explicit and implicit denoising performances of NLMs are obviously pointed.

A future improvement of denoising performance possibly refers to creating a semi-supervised denoising conjunction model. Such model utilizes the denoised MRIs, resulted by DR and D1 thresholding model as uncorrupted image version along with the noisy MRIs, representing corrupted version ones during autoencoder training phase, to reconstruct the original clean image.

This paper should be of interest to readers in the areas of technologies of computing and information science, including data science and applications, computational health informatics, especially applied as a decision support tool for medical image processing.

In most cases, DR and D1 provide the first–second best implicit performances in terms of accuracy and reliability on both simulated, low-detail small-size region-of-interest (ROI) brain lesions and realistic, high-detail large-size ROI brain tumor MRIs.

Why is it that highly trained and seasoned executives fail? On the surface, this doesn’t make sense because they are very successful; yet research in the organization sciences provides no shortage of evidence to prove just that. From the classic Mann Gulch fire disaster of Weick’s famous collapse of sensemaking study, to studies of myopia of learning, escalation of commitment, threat-rigidity, dominant logic, the architecture of simplicity, the Icarus Paradox, to core competencies turning into core rigidities, and navigating new competitive markets using “old” cognitive maps, and many more such examples point to a ubiquitous phenomenon where highly trained and experienced professionals find themselves “stuck” in the heat of battle, unable to move and progress. On the one hand, for some, there is a desperate need for change, but are unable to do so, due to their trained incapacities. On the other hand, some simply cannot see the need for change, and continue with their “business as usual” mentality. For both, their visions of the world shrink, they have a tendency to cling onto their past habitual practices and oversimplify the complexity of the situation. In moments like these: DROP YOUR TOOLS and UNLEARN! This book chapter introduces a framework (grounded in clinical psychology) that has had consistent success in helping seasoned executives and key decision-makers open up the alternatives whenever they find themselves stuck with complexity.