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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ijpe.2005.08.010 Byline: Marvin A. Arostegui (a), Sukran N. Kadipasaoglu (b), Basheer M. Khumawala (b) Keywords: Facility location; Tabu Search; Genetic Algorithms; Simulated Annealing; Combinatorial optimization Abstract: Algorithms to solve Facility Location Problems (FLP) optimally suffer from combinatorial explosion and resources required to solve such problems repeatedly as required in practical applications become prohibitive. In these cases heuristic methods are the only viable alternative. We compare the relative performance of Tabu Search (TS), Simulated Annealing (SA) and Genetic Algorithms (GA) on various types of FLP under time-limited, solution-limited, and unrestricted conditions. The results indicate that TS shows very good performance in most cases. The performance of SA and GA are more partial to problem type and the criterion used. Thus, in general we may conclude that TS should be tried first to the extent that it always yields as good or better results and is easy to develop and implement. Author Affiliation: (a) United States Air Force, USA (b) Bauer College of Business, Decision and Information Sciences Department, University of Houston, 270D Melcher Hall, Houston TX 77204 6027, USA Article History: Received 1 February 2004; Accepted 1 August 2005

This paper is aimed at studying focused cellular manufacturing (FCM). We define FCM as a layout scheme that groups components by end-items and forms cells of machines to fabricate and assemble end-items. It is not classified as a cellular manufacturing layout since it does not attempt to take advantage of process similarities. It also is not classified as a flow shop since there are no machines dedicated to individual operations and the machines are not arranged in a series. The results indicate that the FCM scheme has a batching advantage (i.e., it has to wait less time to batch components before assemble). This advantage dominated the balanced machine utilization benefit of the job shop (JS) layout scheme. The JS was only able to overcome the batching advantage when there were small batch sizes or large setup time magnitudes. Keywords: Focused cellular manufacturing; Simulation

This research investigated in depth the effect of the level and the location of protective capacity relative to the location of the constraint through a simulation experiment. A production line with four stages is simulated. Location of the constraint level of protective capacity, processing time variation and system down time are included as experimental factors. ANOVA is used for the analysis of the results, following by Turkey's means test. The results show that protective capacity has a significant effect on shop performance, however with diminishing returns. The location of the constraint resource also plays a significant role in shop performance. The results also indicate that the extent of benefits derived from protective capacity or constraint location depends on the level of variability and system downtime. Keywords: Flow shop; Constraint resource; Protective capacity.

The effects of improvement programs, such as cellular manufacturing, factory automation, just-in-time systems and total quality management on performance outcomes, including cost, product quality, delivery speed and on-time deliveries, were analyzed by employing the global manufacturing research group (GMRG) data gathered from 1993-95. The GMRG is composed of researchers who are committed to the study and improvement of global manufacturing practices. The partial least squares method for structural equation modeling was used in analyzing and modeling the relationship among the programs and outcomes.

Success factors related to manufacturing planning and control (MPC) practices tend to be influenced by the type of economy a country posses. Data obtained from machine tools and textile industries in 12 countries revealed that nations with free-market economies, such as Japan and Finland, tend to have high success coefficients. On the other hand, nations with planned economies, such as Bulgaria and China, tend to have low success coefficients.

A modified heuristic derived from the fixed-charge facility location methodology is used to deal with the single-item lot sizing problem in production management. The specific problem is considered with the assumption that there are backorders. The heuristic used is not complicated and even intuitive. One of its chief advantages is its flexibility which makes it readily adaptable to similar problems.

Introduction In today's global economy, consumers all over the world want to buy the best products at the lowest prices, regardless of where they are produced. This recent trend has [...]

Europium doped Titanium dioxide (TiO2) nanoparticles were prepared by Sol-Gel technique under varying condition to investigate the effects of Eu3 + doping on the optical properties of Titanium dioxide nanoparticles. The transmittance spectrum is clearly visible at wavelengths 394nm and 416nm, and is a result of electronic transitions of energy level of the Eu3 + ions. . The obtained composites for different doping concentration were analyzed by using Energy Dispersive X-ray Spectroscopy (EDS). The linear and nonlinear optical properties of the composite were studied using the Z-scan technique, and there was an increase in the nonlinear refractive index with an increase in the concentration of the Eu+3, where it reached its highest value, which is 3.01×10-10 at doping 2.3 while the linear absorption coefficient was an inverse proportion, where the highest value was at Pure titanium and it is 1.0296951×10-5 (cm/mw).

Proprotein convertase (PC) deficiency is a rare autosomal recessive disorder caused by mutations in proprotein convertase subtilisin/kexin type 1 (PCSK1). It is characterized by severe malabsorptive early-onset diarrhea, obesity, and systemic endocrinopathies. Only few cases have been reported in the literature; we have add two female sisters with some difference in clinical progress. Herein, we describe two sisters with congenital osmotic diarrhea diagnosed with PC1/3 deficiency, causing malabsorptive diarrhea and enteroendocrine dysfunction, who presented with chronic enteropathy with hypernatremia but with different expressivity. PC1/3 deficiency presents with symptoms and signs that mimic glucose-galactose malabsorption. Because of the clinical paucity and heterogeneity of congenital enteropathies, whole-exome sequencing may be of great help towards early diagnosis and effective treatment.

Novel 0D Ni3V2O8quantum dots (QDs) were decorated on the ultra-thin 2D g-C3N4nanosheet (UCN) using a hydrothermal approach. The embedded Ni3V2O8QDs play a dual role by trapping charge carriers, promoting electron-hole separation, and forming a p-n S-scheme heterojunction, improving the redox potential of the electrons and holes for surface reactions. HR-TEM analysis confirmed that Ni3V2O8QDs with a size varying between 3 to 5 nm have intimate contact with the UCN surface. XPS and ESR spin-trapping agents experiment confirmed the formation of S-scheme heterojunctions between Ni3V2O8QDs and UCN. Photocurrent and PL spectra indicated the synthesized heterostructures have high charge carrier transportation and lower recombination rates. The optimum Ni3V2O8QDs/UCN heterostructure showed the highest photocatalytic hydrogen evolution activity, about 14 times higher than that of pristine UCN. This remarkable improvement in activity can be ascribed to the synergy effect of the S-scheme charge pathway mechanism and the improved light absorption facilitated by the Ni3V2O8quantum dots. As a result, these factors effectively accelerate the migration and transportation of photoinduced charge carriers, offering increased active sites for the H2generation process. This study emphasizes the importance of a well-designed interfacial heterojunction to achieve enhanced photocatalytic performance.

A study analyzes existing empirical evidence to explore the positive impact of radio frequency identification (RFID) on supply chain performance. Analysis indicates that implementation of RFID mainly leads to positive automational effects on supply chain operational processes, and also informational effects on managerial processes.

A comparison is made on cellular manufacturing with focused cellular manufacturing. It was observed that advantages of focused manufacturing are more than cellular manufacturing.

Microvillus inclusion disease (MVID) is a rare autosomal recessive congenital enteropathy characterized by intractable secretory diarrhea. We report a case of MVID variant with a homozygous gene mutation in syntaxin 3 (STX3). The patient is a male Saudi infant who presented shortly after birth with severe vomiting, metabolic acidosis, and mild diarrhea. Electron microscopy study for small intestinal biopsy was consistent with MVID. MYO5B gene mutation was excluded; subsequently, whole exome sequencing (WES) was performed, which revealed homozygous gene mutation in STX3. Using WES in clinical environment can be a useful tool for diagnosing difficult and rare inherited congenital enteropathies.

The kidney-brain interaction has been a topic of growing interest. Past studies of the effect of kidney function on intracerebral hemorrhage (ICH) outcomes have yielded inconsistent findings. Although the second, main phase of the Intensive Blood Pressure Reduction in Acute Cerebral Hemorrhage Trial (INTERACT2) suggests the effectiveness of early intensive blood pressure (BP) lowering in improving functional recovery after ICH, the balance of potential benefits and harms of this treatment in those with decreased kidney function remains uncertain.

A novel nitrogen-doped carbon strontium ferrite (SrFe2O4-NC) nanocomposite with a particle size of 8–10 nm was obtained using the polymeric route. Bimetallic precursors based on iron (III) and strontium chloride were produced with urea and formaldehyde polymers and the precursors were heated at 700 °C in an inert atmosphere to form the SrFe2O4-NC nanocomposite with high surface area (approximately 170.4 m2/g). The prepared SrFe2O4-NC nanocomposite shows ferromagnetic nature with saturation magnetization value of approximately 15 emu/g. Using cyclic voltammetry (CV), galvanic charge-discharge (GCD), and electrochemical impedance spectroscopy (EIS), the supercapacitor capabilities of the SrFe2O4-NC nanocomposite were investigated in 5 M KOH. The SrFe2O4-NC nanocomposite electrode material demonstrates a higher specific capacitance of approximately 895 F/g. High performance of the supercapacitor could be due to their good cyclic stability, high charge - discharge rate, and high energy density. As a result, our focus was on the fabrication of cost-effective and higher performance electrode materials.

The manufacturing operations of Changde Telecommunication Equipment Co was reviewed to improve the the company's shop floor performance. It was found that the telecommunications equipment manufacturer's flow shop system that involves the stages of module production and system assembly was not functioning efficiently. Hence, three modifications were proposed to lower inventories and enhance system performance.

Abu al-Thanaء Shihab al-Din al-Alusi (1802–54) was one of the most prominent ulama of mid-19th century Baghdad. In an era in which the Ottoman drive for modernization and centralization was changing the fabric of society and undermining the power and influence of the ulama class in large parts of the sultanate, al-Alusi was emerging as a powerful local alim, in terms of both his status as a scholar and his influence as a public figure. By the time of his death, the Alusis were becoming firmly established as a recognized ulama family, members of which would continue to play important roles in the intellectual and political life of Iraq and the Arab Mashriq. The grand Alusi, as Abu al-Thanaء al-Alusi was known, however, was, and still is, a controversial Muslim scholar whose intellectual genealogy and leanings seem to be difficult to categorize and too contradictory to pin down. Nothing illustrates the problematic of defining al-Alusi's intellectual and theological attitudes better, perhaps, than the way in which his two sons diverged. Whereas Nuעman Khayr al-Din al-Alusi (1836–99) became one of the most influential Salafi ulama in the late 19th century, his brother, Abdullah, was known as an alim with strong Sufi tendencies. Mahmud Shukri al-Alusi (1857–1924), the son of Abdullah, however, emerged as a highly regarded member of the growing Salafi circles of the major Arab urban centers in the beginning of the 20th century.

•Search for new nanocomposite as energy storage.•A new compound of Bismuth Ferrite Embedded Nitrogen-doped Carbon (BiFeO3-NC) was synthesized.•The newly synthesized compound was subjected to characterization by various electrochemical studies.•The energy storage of the compound was evaluated by cyclic voltammetry.•The Bismuth Ferrite Embedded Nitrogen-doped Carbon (BiFeO3-NC) compound showed an excellent specific capacitance value of ∼811 F/g at 50 mV/s with excellent charge-discharge capacity.

This paper presents the development and application of a heuristic scheduling rule for the Testing Department of a tyre and rubber company. The company had set down five major objectives for this department: (1) minimize average flow-time; (2) maintain an average flow-time of less than two weeks; (3) maintain pre-set maximum individual test flow times; (4) assign a higher priority to important jobs; (5) maintain a balanced mix between truck and passenger tyres. A composite scheduling rule was designed to meet these objectives which contains the following four components: (a) slack-time per remaining operation; (b) shortest processing time; (c) an urgency factor to prioritize important jobs; (d) a balancing factor to enable a desired proportion between truck and passenger tyres. This composite rule is tested against the existing scheduling scheme used by the foreman and against the simple S.P.T. rule. The results are very encouraging.

The mixed integer-linear models that have been used in most analyses of warehouse location problems fail to capture the potential operating efficiencies associated with large scale facilities. This paper presents an algorithm for finding a minimal cost warehouse system design wherein individual warehouses have limited capacities and exhibit economies of scale. The iterative procedure defines and solves a series of conventional transportation problems in order to converge on the optimal system design. The algorithm is well suited to solving large problems of the type commonly encountered in practice.

Flexible manufacturing systems (FMSs) are a class of automated systems that can be used to improve productivity in batch manufacturing. Four stages of decision making have been defined for an FMS—the design, planning, scheduling, and control stages. This research focuses on the planning stage, and specifically in the area of scheduling batches of parts through the system.

Distribution systems designs commonly require the optimal location decisions of regional ware-houses or distribution centers which function as intermediate facilities between plants and customers. This paper deals with such a location problem in which the facilities can handle one of several commodities. We term this problem the multi-commodity facility location problem. A branch and bound algorithm is proposed for solving this problem. Improved bounds are developed for increasing the efficiency of the algorithm. Computational results are provided.

This paper focuses upon the problem of assigning feasible start times to a set of activities making up a project, static job shop, or static flowship type schedules under two constraint sets: (1) no activity may be started until all activities technologically established as its predecessor set have been completed, and (2) the total resource requirements of all activities in process at any time in the schedule must not exceed the level of availability for each of the multiple resource classes. The solution procedure used for these problems is branch and bound, and the resulting complete schedules are optimized with an objective of minimizing the completion time of the entire set of activities. Computational results on tests conducted on a number of randomly generated problem sets with up to 60 activities and six resource classes are presented.

The segregated storage problem consists of determining a minimum cost distribution of products among compartments such that only one product may be stored in a given compartment. This paper explores the computational aspects of using branch and bound methods to solve this problem. Such methods were first suggested for this problem by White and Francis. A variety of approaches are tested, utilizing heuristic node selection and branching decision rules. Three heuristics are also presented which generate solutions for use as initial upper bounds for improving efficiency of the branch and bound procedure or as solutions for very large problems.

The continuous tubular reactor is used for the removal of heavy metals ions [Lead (Pb2+) & Copper (Cu2+)] from polluted water was investigated by using ultraviolet light and hydrogen peroxide. The experimental work gave good results, where the removal efficiency of Pb2+at concentration of 10 ppm was (81.75%) using (15 mL of 30 % H2O2), and 63% using 15 mL of 50% H2O2, while the removal efficiency of Cu2+at 10 ppm was (83.1%) at (15 mL of 30 % H2O2) and the removal efficiency of Cu2+was (60.4%) after adding (15 mL of 50% H2O2) during 90 min. The dose of H2O2increased with the increases in initial concentration of the heavy metal ions.

The increased use and mastery of ceasarian section for deliveries and the refinement of technologies for assisted delivery in the setting of dfficult second stage of labour have made intrapartum deaths more rare and modern obstetrical pracices are rarely accompanied by the classic forceps related intracranial injuries. We document a novel pattern of intracranial injury in three cases of neonatal death following prolonged labor, of which two out of three required vacuum and forceps.All three showed similar bilateral parasagittal intraparenchymal haemorrhages and cerebral edema, in a pattern reminiscent of “gliding contusion, as well as subgaleal haemorrhage of varying amout. Two out of the three cases showed parietal bone fractures and one demonstrated extensive craniolcuniae. We briefly discuss the significance of these findings and implications for future cases.LEARNING OBJECTIVESThis presentation will enable the learner to:1.Explore the current theories leading to neonatal death in prolonged labor2.Summarize the known pathological findings associated with vacuum and forceps3.Discuss the significance of intraparenchymal hematoma in the setting of prolonged delivery

The relationship of inflammatory bowel disease (IBD) and chronic recurrent multifocal osteomyelitis (CRMO) is understood as extraintestinal rheumatic manifestations. CRMO is a chronic, relapsing, inflammatory, noninfectious disorder of the skeletal system of unknown origin. The disease course is not always recurrent. The association of CRMO and ulcerative colitis (UC) is very rarely reported. We report a case of a 10-year-old Saudi female who was diagnosed with CRMO, when she developed fever in association with left foot pain, and ulcerative colitis was confirmed endoscopically and histologically based on a previous settled diarrheal illness and severe iron deficiency anemia which required blood. Both conditions responded well to IBD therapy. To the best of our knowledge, this is the first reported case of chronic, multifocal osteomyelitis associated with pediatric UC in Saudi Arabia. This report supports the use of IBD therapy in treating CRMO.

An abstract of the article "Enhancing product recovery value in closed-loop supply chains with RFID," by John K. Visic, Suhong Li and Basheer M. Khumawala, that was published in the fall 2007 issue of "Journal of Managerial Issues" is presented.