Influence of fire source locations on the actuation of wet-type sprinklers in an office fire

An experiment is conducted on a full-scale model office and an actual sprinkler system to explore the influence of fire source locations on sprinkler actuation. The office space is a brick structure that measures 5.7 m in interior length, 4.7 m in width and 2.4 m in ceiling height, and equipped with a sprinkler system. The investigated fire source (100 kW LPG burner) locations include the room center, wall centers, room corner, and other locations at different distances from sprinklers. The results show that actuation of the sprinklers is affected by the fire source locations and the heat conduction properties of the glass temperature-sensing bulb. Average actuation time of all the tests is 102 s, around 40 s faster than if the fire source is located in the room center. For fire sources in corners, sprinklers are quickly activated at the experimental time 75 s, showing concentrated hot gas flow.     

Effects of CCEP and Sc on superplasticity of Al–5.6Mg–0.7Mn alloys

Trace amount (0.3?wt%) of scandium is added to Al–5.6Mg–0.7Mn alloy to form uniformly distributed Al₃Sc precipitates for producing a fine-grained and stable microstructure at high temperature through cross-channel extrusion process. Superplasticity and hot workability of the Sc-containing Al–5.6Mg–0.7Mn alloy, after extrusion, are also examined. The result indicates that Al–5.6Mg–0.7Mn alloys with and without 0.3?wt% Sc after extrusion of six passes at 300°C, fine-grained structures were observed with grain sizes of 1–2?µm and improvement of mechanical properties. Furthermore, Al₃Sc phase can effectively retard recrystallization to increase the thermal stability and remain equiaxed. The elongation of Al–5.6Mg–0.7Mn alloy with Sc addition to failure is extended to 873% maximum at high temperature of 450°C at strain rate of 1?×?10^?1?s^?1after six passes in the CCEP.     

Strength prediction of multi-layer plain weave textile composites using the direct micromechanics method

Previously developed micromechanical methods for stiffness and strength prediction are adapted for analysis of multi-layer plain weave textile composites. Utilizing the direct micromechanics method (DMM) via finite element modeling, three methods are presented: (a) direct simulation of a multi-layer plain weave textile composite; (b) micromechanical analysis of a single layer of interest from the force and moment resultants acting on that layer; and (c) application of the previously developed quadratic stress-gradient failure theory to the layer of interest. In comparison to direct modeling, the other two techniques show only 5% difference over a number of random test cases. Several practical design examples of strength prediction are included to illustrate the importance and accuracy of method implementation.     

New hybrid COPRAS-G MADM Model for improving and selecting suppliers in green supply chain management

Greening the supply chain is an increasingly important concern for many business enterprises and a challenge for logistics management. Critical functions within green supply chain management are internal improvements and selection of green suppliers. This study proposes a novel, hybrid model that addresses dependent relationships between various criteria and the vague information coming from decision-makers. The Decision-making Trial and Evaluation Laboratory (DEMATEL) technique structures the relationships among criteria, thereby constructing an influential network relationship map (INRM). Meanwhile the DEMATEL-based, analytical network process (ANP) method aids in obtaining influential weights of the criteria. Decision-makers may hold diverse opinions and preferences due to incomplete information, differences in knowledge or simply conflicts that are inherent between various departments. This can make it difficult to judge the performance of alternatives. One remedy is to apply a modified COmplex PRoportional ASsessment of alternatives with Grey relations. Next, this is applied to improve each criterion for integration of the performance values obtained in closing the aspiration level from different expert opinions based on INRM. An empirical example using data from a Taiwanese electronics company is provided to demonstrate our proposed method. The results can provide firms with a knowledge-based understanding of the source of some problems, thus reducing the performance gaps and closing the aspiration levels. Finally, there is a discussion on certain managerial implications.     

Cancer-Targeting Nanoparticles for Combinatorial Nucleic Acid Delivery

Nucleic acids are a promising type of therapeutic for the treatment of a wide range of conditions, including cancer, but they also pose many delivery challenges. For efficient and safe delivery to cancer cells, nucleic acids must generally be packaged into a vehicle, such as a nanoparticle, that will allow them to be taken up by the target cells and then released in the appropriate cellular compartment to function. As with other types of therapeutics, delivery vehicles for nucleic acids must also be designed to avoid unwanted side effects; thus, the ability of such carriers to target their cargo to cancer cells is crucial. Classes of nucleic acids, hurdles that must be overcome for effective intracellular delivery, types of nonviral nanomaterials used as delivery vehicles, and the different strategies that can be employed to target nucleic acid delivery specifically to tumor cells are discussed. Additonally, nanoparticle designs that facilitate multiplexed delivery of combinations of nucleic acids are reviewed.     

Harmonic analysis in DC electrified transit railway systems consisting of uncontrolled bridge rectifiers with commutation impedances

Abstract

The paper presents a new formulation of harmonic current injection of the 6‐pulse uncontrolled bridge rectifier with commutation impedance. In cooperation with a train simulator developed earlier, the proposed harmonic source model is applied in a harmonic analysis program to comprehensively simulate the harmonic penetration in the Blue Line of Taipei Rapid Transit Systems (TRTS). Both frequency scans and harmonic distortion calculations were performed for various system component models. Simulation results indicated that both the voltage and current harmonic distortions in the Blue Line of TRTS were improved by use of 24‐pulse rectifiers. The application of further harmonic suppression schemes in traction networks to alleviate the harmonic distortions can be achieved using the simulated results.     

Fabrication of carbon nanotubes field emission cathode by composite plating

Carbon nanotubes (CNTs) have high aspect ratio and have great potential to be applied as the field emission cathode because of its large field enhancement factor. In this work, a high performance carbon nanotube field emission cathode (CNTFC) was fabricated by using a composite plating method. The CNTs were purified by acid solutions and then dispersed in electrobath with nickel ions at temperatures of 60, 70, or 80 degrees C for the electroless plating process on glass substrate. The resulting CNT-Ni composite film has strong adhesion on the glass substrate. The degree of graphitization and the microstructure of the CNTFCs were studied by Raman spectroscopy and scanning electron microscopy. The field emission properties of the CNTFCs show a low turn-on electric field E(on) of about 1.2 V/microm, and a low threshold electric field E(th) of about 1.9 V/microm. Such a composite plating method could be applied to the fabrication of large area CNT field-emission displays.     

High-speed mass analysis of whole erythrocytes by charge-detection quadrupole ion trap mass spectrometry

Herein, we report an application of charge-detection quadrupole ion trap mass spectrometry to the measurement of total dry masses of mammalian and poultry erythrocytes evaporated/ionized by laser-induced acoustic desorption. The method is rapid and widely applicable. Eight different types of red blood cells (RBCs) have been successfully analyzed, including those of human, goat, cow, mouse, pig, and chicken. The measured mean masses (weights per corpuscle) range from 0.58 x 10(13) Da (9.6 pg) of goat RBCs to 2.80 x 10(13) Da (46.5 pg) of chicken RBCs. The total dry weights determined for human RBCs from a healthy male adult, a patient with iron-deficiency anemia, and a patient with thalassemia are 34.8, 28.8, and 20.6 pg, respectively. These weights, except that of thalassemia, are all approximately 10% higher than their corresponding mean corpuscular hemoglobin values determined by a commercial automated hematology analyzer. The mass distribution profiles of the cells are all near-Gaussian, with a standard deviation of 15% for the normal human RBCs. The deviation increases significantly to 20% for RBCs with thalassemia characteristics and 27% for RBCs with iron-deficiency anemia characteristics. All the observations are in accord with their corresponding mean corpuscular volume measurements, indicating an increase in anisocytosis (variation in RBC size) in the anemic samples. Our results suggest a broad and promising application of this new technology to high-speed mass analysis of RBCs and other biological whole cells as well.     

On two mixed variational principles for thick laminated composite plates

The basic behavior of the shear deformation plate theories derived from the recently proposed Reissner's and Jing-Liao's functionals is studied in this paper. The difference between these two functionals is on the energy form of transverse normal stress. In Reissner's functional, the transverse normal stress has to be assumed as well as displacements and transverse shear. On the other hand, the independent variables in Jing-Liao's functional include only displacements and transverse shear. The comparison of these functionals is made through two examples, one with assumed transverse normal stress and the other without. It is found that for the cases studied in this paper Jing-Liao's functional provides a simpler, sometimes even better, alternative approach than Reissner's functional in formulating shear deformation theory of thick plates.     

A new procedure for decoding cyclic and BCH codes up to actualminimum distance

The paper presents a new procedure for decoding cyclic and BCH codes up to their actual minimum distance. It generalizes the Peterson decoding procedure and the procedure of Feng and Tzeng (1991) using nonrecurrent syndrome dependence relations. For a code with actual minimum distance d to correct up to t=[(d-1)/2] errors, the procedure requires a (2t+1)×(2t+1) syndrome matrix with known syndromes above the minor diagonal and unknown syndromes and their conjugates on the minor diagonal. In contrast to previous procedures, this procedure is primarily aimed at solving for the unknown syndromes instead of determining an error-locator polynomial. Decoding is then accomplished by determining the error vector as the inverse Fourier transform of the syndrome vector (S₀, S₁, S_n-1). The authors show that with this procedure, all binary cyclic and BCH codes of length <63 (with one exception) can be decoded up to their actual minimum distance. The procedure incorporates an extension of their fundamental iterative algorithm and a majority scheme for confirming the true values computed for the unknown syndromes. The complexity of this decoding procedure is O(n³)