Recovery of sensor embedded washing machines using a multi-kanban controlled disassembly line

Product recovery involves the recovery of materials and components from returned or end-of-life products. Disassembly, an element of product recovery, is the systematic separation of an assembly into its components, subassemblies or other groupings. Stricter environmental regulations together with dramatic decrease in natural resources and landfills have increased the importance of disassembly as all product recovery options require some level of disassembly. Due to changes made during the lifetime of a product by customers or service personnel, the number and the version of components prior to disassembly is unknown. Customers may also discriminate between and demand different versions of components. The existence of non-functional components further adds to the uncertainty associated with disassembly yield. Sensors implanted into products during their production can address this uncertainty by providing information on the number, condition and version of components prior to disassembly. In this study, we evaluate the impact of sensor embedded products (SEPs) on the various performance measures of a washing machine (WM) disassembly line controlled by a multi-kanban system, which takes into consideration the highly stochastic behavior of the line while managing material and kanban flows. First, separate design of experiments studies based on orthogonal arrays are performed for conventional products and SEPs. In order to observe the response of each experiment, detailed discrete event simulation (DES) models for both types of products are developed considering the precedence relationships among the components of a WM. Then, pair-wise t-tests are conducted to compare the two cases based on different performance measures. According to the results, SEPs provide significant reductions in all costs (viz., backorder, holding, disassembly, disposal, testing and transportation) while increasing revenue and profit.     

Identification of the parental origin of polysomy in two 49,XXXXY cases

Cutaneous findings can be useful in establishing the diagnosis and treatment of hospitalized patients. Observation and identification of cutaneous abnormalities can improve the accuracy of diagnosis and result in improved patient care. We set out to determine the prevalence of cutaneous abnormalities in hospitalized pediatric patients in a hospital and how often these findings were noted and properly diagnosed by the admitting team of physicians. Children with medical problems admitted to Kosair Children's Hospital during the month of January 1995 were randomly selected for a skin examination, which was performed within 24 to 28 hours of admission. Parental consent was required prior to admission into the study. Of 117 patients offered participation, 110 accepted. Physical findings were noted and in addition the completeness of charting by the admitting physician and the relationship of any cutaneous findings to admitting diagnosis were noted. One hundred five of the 110 patients (95%) had cutaneous findings consisting of either a "rash" or a "congenital lesion." Fifty-one had more than one cutaneous finding noted on examination. Dermatitis was the most common diagnosis made, followed by pigmented lesions and congenital vascular malformations of all types. In 35 of the 105 patients with a dermatologic diagnosis, the dermatologic diagnosis related directly to the admitting diagnosis. In only 22 of these 35 (63%) was the cutaneous involvement noted by the admitting physician. In 9 of the 110 cases (8%), the findings on dermatologic examination altered the primary diagnosis and/or treatment. Cutaneous findings are very common in the hospitalized pediatric patient. The diagnosis, charting, and treatment of dermatologic conditions by the primary pediatric team were often incomplete, although an expert cutaneous examination can be critical to patient care.     

Synthesis and characterization of 2‐hydroxyethylmethacrylate/2‐(3‐indol‐yl)ethylmethacrylamide‐based novel hydrogels as drug carrier with in vitro antibacterial properties

In this study, a new cationic monomer 2‐(3‐indol‐yl)ethylmethacrylamide (IEMA) derived from tryptamine was synthesized in a single step and characterized by Fourier transform infrared (FTIR), ¹H‐NMR, and ¹³C‐NMR. Then, one‐step preparation of novel poly[2‐hydroxyethylmethacrylate‐c‐2‐(3‐indol‐yl)ethylmethacrylamide], or p(HEMA‐c‐IEMA), copolymeric hydrogels has been performed successfully with IEMA and 2‐hydroxyethylmethacrylate (HEMA) as monomers using free radical aqueous polymerization. The hydrogels were characterized with scanning electron microscopy, FTIR, elemental analysis, thermogravimetric analysis, and texture profile analysis instruments. p(HEMA‐c‐IEMA) hydrogels were used for swelling, diffusion, drug release, and antibacterial activity studies. The drug‐release behavior of the hydrogels was determined as a function of time at 37 °C in pH 1.2 and 7.2. The swelling and drug‐release studies showed that an increased IEMA amount caused a higher increase in swelling and drug‐release values. Additionally, zero‐order, first‐order, and Higuchi equation kinetic models were applied to the drug‐release data, and the data fit well in the Higuchi model, and the Peppas power‐law model was applied to the release mechanism. Finally, the antibacterial activities of the hydrogels were screened against Gram‐positive bacteria (Bacillus cereus and Staphylococcus aureus) and Gram‐negative bacteria (Escherichia coli and Salmonella typhimurium). © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45550.     

Double Threshold Energy Based Spectrum Sensing with Copulas

Wireless Personal Communications - As it is known, Energy based detection is widely used in Cognitive Radio and radar systems. In order to reduce the disruptive effects of wireless channels, Energy...     

Multiresponsive polymeric particles with tunable morphology and properties based on acrylonitrile (AN) and 4-vinylpyridine (4-VP)

We report the synthesis of amphiphilic, pH and magnetic field sensitive polymeric particles obtained from the modification of poly(acrylonitrile-co-4-vinylpyridine) (p(AN-c-4-VP)) core-shell nanoparticles. The magnetic metal nanoparticles were encapsulated in the microemulsion during the polymerization to achieve magnetic-p(AN-c-4-VP)-composites with various morphology. We further chemically modified each component of p(AN-c-4-VP) particles and its composite to tune the hydrophilicity of the particles. Modification of nitrile (hydrophobic) groups to amidoxime (hydrophilic) groups by amidoximation reaction on AN, and quarternization of nitrogen on pyridine ring of 4-VP were carried out to tune the hydrophilicity and the charge of the particles. The modification also performed on magnetic responsive composites after inclusion of separately prepared magnetic Fe₃O₄ nanoparticles. It was further demonstrated that these multiresponsive particles can be used as drug carrier. A nonsteroidal and anti-inflammatory drug Naproxen was used as a model active agent for drug loading and the release studies from (p(AN-c-4-VP) based particles in phosphate buffer solution (pH = 7.4) at ambient temperature.     

Comparison of economic benefits of sensor embedded products and conventional products in a multi-product disassembly line

Sensors embedded into products during the production process are important data acquisition tools for after-sale products’ condition monitoring. By facilitating data collection from critical components in a product, these sensors help companies predict components and/or products failures during product usage. They are also very useful at the end-of-life (EOL) of products. Using sensor information, the conditions, types and remaining lives of components in an EOL product can be determined prior to actual disassembly. In this study, we assess the use of sensors in determining the steps in EOL processing of products. In particular, we evaluate the impact of sensor embedded products (SEPs) on various performance measures of an appliance disassembly line controlled by a multi-kanban system. First, separate design of experiments studies based on orthogonal arrays are carried out for conventional products (CPs) and SEPs. In order to calculate the response values for each experiment, detailed discrete event simulation models of both cases are developed considering the precedence relationships among the components together with the routing of different appliance types through the disassembly line. Then, pair-wise t-tests are conducted to compare the two cases based on different performance measures. The test results show the superiority of SEPs over CPs with respect to all costs (viz., disassembly, disposal, testing, backorder, transportation, holding) as well as revenue and profit.