Production planning under dynamic product environment: a multi-objective goal programming approach

Production planning is a complicated task that requires cooperation among multiple functional units in any organization. In order to design an efficient production planning system, a good understanding of the environment in terms of customers, products and manufacturing processes is a must. Although such planning exists in the company, it is often incorrectly structured due to the presence of multiple conflicting objectives. The primary difficulty in modern decision analysis is the treatment of multiple conflicting objectives. A formal decision analysis that is capable of handling multiple conflicting goals through the use of priorities may be a new frontier of management science. The objective of this study is to develop a multi objective goal programming (MOGP) model to a real-life manufacturing situation to show the trade-off between different some times conflicting goals concerning customer, product and manufacturing of production planning environment. For illustration, two independent goal priority structures have been considered. The insights gained from the experimentation with the two goal priority structures will guide and assist the decision maker for achieving the organizational goals for optimum utilization of resources in improving companies competitiveness. The MOGP results of the study are of very useful to various functional areas of the selected case organization for routine planning and scheduling. Some of the specific decision making situations in this context are: (i). the expected quality costs and production costs under identified product scenarios, (ii).under and over utilization of crucial machine at different combinations of production volumes, and (iii). the achievement of sales revenue goal at different production volume combinations. The ease of use and interpretation make the proposed MOGP model a powerful communication tool between top and bottom level managers while converting the strategic level objectives into concrete tactical and operational level plans.

Boosting autophagy in the diabetic heart: a translational perspective

Diabetes, obesity, and dyslipidemia are main risk factors that promote the development of cardiovascular diseases. These metabolic abnormalities are frequently found to be associated together in a highly morbid clinical condition called metabolic syndrome. Metabolic derangements promote endothelial dysfunction, atherosclerotic plaque formation and rupture, cardiac remodeling and dysfunction. This evidence strongly encourages the elucidation of the mechanisms through which obesity, diabetes, and metabolic syndrome induce cellular abnormalities and dysfunction in order to discover new therapeutic targets and strategies for their prevention and treatment. Numerous studies employing both dietary and genetic animal models of obesity and diabetes have demonstrated that autophagy, an intracellular system for protein degradation, is impaired in the heart under these conditions. This suggests that autophagy reactivation may represent a future potential therapeutic intervention to reduce cardiac maladaptive alterations in patients with metabolic derangements. In fact, autophagy is a critical mechanism to preserve cellular homeostasis and survival. In addition, the physiological activation of autophagy protects the heart during stress, such as acute ischemia, starvation, chronic myocardial infarction, pressure overload, and proteotoxic stress. All these aspects will be discussed in our review article together with the potential ways to reactivate autophagy in the context of obesity, metabolic syndrome, and diabetes

Low-Power, Low-Cost, & High-Performance Digital Designs : Multi-bit Signed Multiplier design using 32nm CMOS Technology

Binary multipliers are ubiquitous in digital hardware. Digital multipliers along with the adders play a major role in computing, communicating, and controlling devices. Multipliers are used majorly in the areas of digital signal and image processing, central processing unit (CPU) of the computers, high-performance and parallel scientific computing, machine learning, physical layer design of the communication equipment, etc. The predominant presence and increasing demand for low-power, low-cost, and high-performance digital hardware led to this work of developing optimized multiplier designs. Two optimized designs are proposed in this work. One is an optimized 8 x 8 Booth multiplier architecture which is implemented using 32nm CMOS technology. Synthesis (pre-layout) and post-layout results show that the delay is reduced by 24.7% and 25.6% respectively, the area is reduced by 5.5% and 15% respectively, the power consumption is reduced by 21.5% and 26.6% respectively, and the area-delay-product is reduced by 28.8% and 36.8% respectively when compared to the performance results obtained for the state-of-the-art 8 x 8 Booth multiplier designed using 32nm CMOS technology with 1.05 V supply voltage at 500 MHz input frequency. Another is a novel radix-8 structure with 3-bit grouping to reduce the number of partial products along with the effective partial product reduction schemes for 8 x 8, 16 x 16, 32 x 32, and 64 x 64 signed multipliers. Comparing the performance results of the (synthesized, post-layout) designs of sizes 32 x 32, and 64 x 64 based on the simple novel radix-8 structure with the estimated performance measurements for the optimized Booth multiplier design presented in this work, reduction in delay by (2.64%, 0.47%) and (2.74%, 18.04%) respectively, and reduction in area-delay-product by (12.12%, -5.17%) and (17.82%, 12.91%) respectively can be observed. With the use of the higher radix structure, delay, area, and power consumption can be further reduced. Appropriate adder deployment, further exploring the optimized grouping or compression strategies, and applying more low-power design techniques such as power-gating, multi-Vt MOS transistor utilization, multi-VDD domain creation, etc., help, along with the higher radix structures, realizing the more efficient multiplier designs

Some STL file generation issues in rapid prototyping

The stereolithography (STL) file format was introduced by 3D Systems and has become the de facto industry standard. However, this is not an ideal format due to the existence of some inherent problems. Due to the non- robustness of commercial CAD systems, the choice of tolerance is a major issue when saving STL files. These tolerances will affect the file size, the number of triangular facets and the number of STL file errors. The primary focus of this paper is to outline the relationship between tolerance and these issues in the conversion of CAD models to STL files. To meet the aim of this study, the file size and the number of triangular facets were recorded after STL file generation while the number of file errors was obtained after scanning. Some interesting relationships were noticed and are documented. It is noted that the number of errors decreases with increasing tolerance and that in general there are more errors in the ASCII file format than in the binary equivalent. This paper is intended to provide to the practitioner an idea of how the different factors mentioned are affected by tolerance and allow them to choose the best values based on the finding

RFID Tag Reader Designs for Retail Store Applications

Current RFID tag readers do not do much more than reading the tags and transmitting that information to a central server for processing. This places a heavy burden on the central server to keep track of all the incoming data from the reader when it can be spending its time more gainfully on other tasks. We propose building some intelligence into RFID tag readers so that they can process some of the data themselves and reduce the load on the central server. We discuss the technical details of building this intelligence in the four key functions of tag readers: (A) Automatic initialization of the tag readers, (B) Automatic identification of misplaced items, (C) Automatic generation of shelf replenishment alerts, and (D) Automatic generation of reorder alerts. In addition, we discuss possible network designs for interconnecting the tag readers and the central transaction server at the retail store. We provide a database model for storing transactions generated by RFID tag reads. We discuss how the current enterprise architectures can be modified to accommodate RFID transactions

Slicing issues in CAD translation to STL in rapid prototyping

The rapid prototyping (RP) process is being used widely with great potential for rapid manufacturing of functional parts. The RP process involves translation of the CAD file to STL format followed by slicing of the model into multiple horizontal layers, each of which is reproduced physically in making the prototype. The thickness of the resulting slices has a profound effect on the surface finish and build time of the prototype. The purpose of this paper is to show the effects of slice thickness on the surface finish, layering error, and build time of a prototype, as well as to show how an efficient STL file can be developed. Three objects were modeled and STL files were generated. One STL file for each object was sliced using different slice thicknesses, and the build times were obtained. Screenshots were used to show the slicing effect on layering error and surface finish and to demonstrate the means to a more efficient STL file. From the results, it is clear that the surface finish and build time are important factors that are affected by slice thicknes

Thigh Abscess Caused by Yersinia enterocolitica in an Immunocompetent Host

Yersinia enterocolitica is primarily a gastrointestinal tract pathogen known to cause gastroenteritis, although it may produce extra-intestinal infections like sepsis and its sequelae. However, primary cutaneous infections are extremely rare. We present a case of Y. enterocolitica thigh abscess in an immunocompetent adult. The portal of entry is unclear in this case. He did many outdoor activities that involved skin injuries and exposure to soil and contaminated water. Hence, direct inoculation as a result of exposure to contaminated water is postulated in the absence of evidence for a gastrointestinal route of infection

Three-dimensional flow instability in a lid-driven isosceles triangular cavity

Linear three-dimensional modal instability of steady laminar two-dimensional states developing in a lid-driven cavity of isosceles triangular cross-section is investigated theoretically and experimentally for the case in which the equal sides form a rectangular corner. An asymmetric steady two-dimensional motion is driven by the steady motion of one of the equal sides. If the side moves away from the rectangular corner, a stationary three-dimensional instability is found. If the motion is directed towards the corner, the instability is oscillatory. The respective critical Reynolds numbers are identified both theoretically and experimentally. The neutral curves pertinent to the two configurations and the properties of the respective leading eigenmodes are documented and analogies to instabilities in rectangular lid-driven cavities are discussed

Synergies in the Application of Industry 4.0 and Lean Manufacturing at a Product Label Manufacturer – A Discrete Event Simulation Case Study

Industry 4.0 is a manufacturing philosophy and industry standard for the design of Cyber-Physical Production Systems. The aim of Industry 4.0 is the creation of a smart manufacturing system. A smart system which applies novel applications of developed and current technologies to simplify complex work and enable waste averse production. It is based on the concepts of data-driven decision support services, Horizontal and Vertical Information Technology-Operations Technology value-chain integration, decentralized control and flexible production. Lean Manufacturing is a value-to-customer- focused manufacturing philosophy which applies procedures designed to ingrain waste reduction and efficient, competency- building practices into workplace culture. The aim of this paper is to examine the synergistic benefits of these manufacturing philosophies on a local firm using Discrete Event Simulation. The key performance indicators of Flow Time, Waiting Time and Work in Process were used to determine the efficacy of the models investigated. The study results indicated a 52 %, 57 % and 58 % improvement in the respective metrics of the best performing proposed model when com-pared to the existing system

An integrated approach towards achieving agility in design and development of a broken free-form object / Fahraz Ali and Boppana V. Chowda

This paper attempts to introduce a unified approach for design and development of a broken free-form object in order to achieve agility in the process. A combination of reverse engineering (RE), re-engineering (ReE) and rapid product development (RpD) approach has been tailored to address the design and development issues of the broken free-form object. A broken clutch shoe from a centrifugal clutch assembly is selected for demonstrating the efficacy of the proposed integrated methodology. To achieve agility in the process, RE is employed for quick recovery of technical data and re-construction of the entire part model. Subsequently, re-engineering is sustained through geometric dimensioning and tolerancing (GD&T) which is used as a validation tool for inspection/comparison of the reference and digitized parametric computer aided design (CAD) models. Furthermore integration of finite element analysis (FEA) is performed iteratively for optimization of influential factors of the part such as feature characteristics and material properties. Finally, computer aided manufacturing (CAM) system is introduced for rapid prototyping of the selected part. This process can manifest itself into similar industrial situations to achieve agility in the product design and development process so that the developed part can be distributed quickly to the customer. Design for better performance of the product in a short turnaround time is the main outcome of this research