Analytical considerations of flow boiling heat transfer in metal-foam filled tubes

Flow boiling in metal-foam filled tube was analytically investigated based on a modified microstructure model, an original boiling heat transfer model and fin analysis for metal foams. Microstructure model of metal foams was established, by which fiber diameter and surface area density were precisely predicted. The heat transfer model for flow boiling in metal foams was based on annular pattern, in which two phase fluid was composed by vapor region in the center of the tube and liquid region near the wall. However, it was assumed that nucleate boiling performed only in the liquid region. Fin analysis and heat transfer network for metal foams were integrated to obtain the convective heat transfer coefficient at interface. The analytical solution was verified by its good agreement with experimental data. The parametric study on heat transfer coefficient and boiling mechanism was also carried out

Study on the mortality of the stored-grain insects adults in different concentrations of low oxygen

During this research, adults of Liposcelis bostrychophila Badonnel, Oryzaephilus surinamensis (Linnaeus), Tribolium confusum Jacquelin du Val, two strains of Tribolium castaneum (Herbst) (from Zhongshan and Yiyang), Sitophilus oryzae (Linnaeus) and Sitophilus zeamais Motschulsky were first kept in various low oxygen atmospheres whose concentrations were 0%, 1% and 2% for different exposure times, then in the normal atmosphere. The data and trend of mortality changes accompanied by the low oxygen concentration and exposure time were gained after this research. Results indicate that there were obvious inter-specific differences among the test insects in the sensitivity to low oxygen atmosphere, and the sensitivity declined as follows: L. bostrychophila, O. surinamensis, T. confusum, T. castaneum, S. oryzae and S. zeamais. The insects of closely related species presented diverse responses to the low oxygen stress. Tribolium confusum and T. castaneum showed a very dissimilar sensitivity to the low oxygen atmosphere, but there was no obvious difference between S. oryzae and S. zeamais. A fast lethal effect on the adults of L. bostrychophila, O. surinamensis, T. confusum and T. castaneum was observed when exposed to 0% oxygen. At 1% and 2% oxygen atmosphere, the mortality level of T. castaneum exceeded 60% and 80%, respectively. The lethal effect of 2% was more efficient than 1% oxygen, which was the same as S. oryzae and S. zeamais at 2% oxygen atmospheres. The mortality of S. oryzae and S. zeamais at 1% and 2% oxygen concentration was higher than at 0%, and the mortality of these two insects might be higher under the condition of a small amount of oxygen. At 1% and 2% oxygen atmosphere, the growth trend of the cumulative mortality of T. confusum and T. castaneum generally conformed to the classical model of the logistic formula which indicated the response of insect pests when applying common insecticide. These results are useful to extend the control technology of stored-grain insects with low oxygen universally.Keywords: Low oxygen; Stored-grain insect; Mortality; Treatment duratio

Unsupervised Diverse Colorization via Generative Adversarial Networks

Colorization of grayscale images has been a hot topic in computer vision. Previous research mainly focuses on producing a colored image to match the original one. However, since many colors share the same gray value, an input grayscale image could be diversely colored while maintaining its reality. In this paper, we design a novel solution for unsupervised diverse colorization. Specifically, we leverage conditional generative adversarial networks to model the distribution of real-world item colors, in which we develop a fully convolutional generator with multi-layer noise to enhance diversity, with multi-layer condition concatenation to maintain reality, and with stride 1 to keep spatial information. With such a novel network architecture, the model yields highly competitive performance on the open LSUN bedroom dataset. The Turing test of 80 humans further indicates our generated color schemes are highly convincible

Determination of glyphosate and aminomethylphosphonic acid in soybean samples by high performance liquid chromatography using a novel fluorescent labeling reagent

A highly sensitive pre-column derivatization HPLC method for simultaneous determination of glyphosate (GLYP) and its major metabolite aminomethylphosphonic acid (AMPA) in soybean samples was developed. The analytes were labeled with a novel fluorescent labeling reagent 3,6-dimethoxy-9-phenyl- 9H-carbazole-1-sulfonyl chloride (DPCS-Cl) at 70 °C for 25 min. The optimized concentration of DPCS-Cl was 25 μg mL-1 and the molar ratio of analytes to DPCS-Cl was 1:4.2. The derivatives were separated on a reversed-phase column by gradient elution and were monitored with fluorescence detection at 318 nm (excitation) and 440 nm (emission). The method linearity, calculated for GLYP and AMPA, had a correlation coefficient greater than 0.999. The detection limits for GLYP and AMPA were 0.02 ng mL-1 and 0.01 ng mL-1 (S/N = 3), respectively. In addition, a simple sample pretreatment for the soybean samples was developed to extract GLYP and AMPA. The recovery of extraction was more than 95%. Then, this method gave the detection limits of 0.002 mg kg-1 for GLYP and 0.001 mg kg-1 for AMPA in soybean samples. This HPLC method was applied to the determination of glyphosate and AMPA in soybean samples with its merits of simplicity in pretreatment, rapidity in derivatization, stability of the derivatives and high sensitivity. © 2013 The Royal Society of Chemistry

Agent-based real-time assembly line management for wireless job shop environment

Recent developments in wireless technologies have created opportunities for developing next-generation manufacturing systems with real-time traceability, visibility and interoperability in shop floor planning, execution and control. This paper discusses how to deploy wireless and intelligent technologies to convert physical objects in manufacturing systems into smart objects to introduce and improve the interoperability and visibility between them and thus with manufacturing decision support systems. A reference architecture for wireless manufacturing (WM) is proposed where three types of smart objects are identified. At the same time, the concept of smart object agent (SOA) is presented and the corresponding framework of smart objects management system (SOMS) is constructed. Under this framework and the concept of SOA, a SOA-based WM environment is studied and demonstrated using a near real-life simplified product assembly line for the collection and synchronization of the real-time field data from manufacturing workshops. © 2010 IEEE.published_or_final_versionThe IEEE International Conference on Mechatronics and Automation (ICMA) 2010, Xi'an, China, 4-7 August 2010. In Proceedings of the IEEE International Conference on Mechatronics and Automation, 2010, p. 2013-201

Improvement of daptomycin yield by overexpression of the accessory genes of daptomycin gene cluster

The effects of the accessory genes flanking the non-ribosomal peptide synthetase (NRPS) genes on daptomycin production were investigated by overexpression under the control of ermE* promoter via the integrative Escherichia coli–Streptomyces vector pIB139. The yield of daptomycin was promoted significantly when either of the upstream accessory genes of dptE and dptF or downstream accessory genes of dptG, dptH, dptI and dptJ was overexpressed individually or by a combined manner. The yield of daptomycin further increased to 869 ± 25 mg/L, approximately 42.6% higher than the parental strain of LC-54-16, when all of the six upstream and downstream accessory genes were overexpressed simultaneously. The results above suggested that the upstream and downstream accessory genes of NRPS had positive cooperativity in the biosynthesis of daptomycin. The transcriptional levels of both the upstream and the downstream accessory genes of NRPS in HP-EJ were approximately 2.5-fold as high as that in the parental strain of LC-54-16.Key words: Daptomycin production, accessory genes of NRPS, overexpression, Streptomyces roseosporus

RFID-enabled real-time manufacturing information tracking infrastructure for extended enterprises

In extended enterprises, real-time manufacturing information tracking plays an important role and aims to provide the right information to the right person at the right time in the right format to achieve optimal production management among the involved enterprises. However, many enterprises are caused by lack of timely, accurate and consistent manufacturing data. The laggard information transfer flow and the unmatched information transfer method bring extended enterprises much more uncertainty and unknowingness. This paper proposes a RFID-enabled real-time manufacturing information tracking infrastructure (RTMITI) to address the real-time manufacturing data capturing and manufacturing information processing methods for extended enterprises. Following the proposed infrastructure, the traditional manufacturing resources such as employees, machines and materials are equipped with RFID devices (Readers and Tags) to build the real-time data capturing environment. In addition, a series of manufacturing information processing methods are established to calculate and track the real-time manufacturing information such as real-time manufacturing cost, progress, WIP (Work-in-progress) inventory etc. in parts/assemblies/products at machines/shop floors/enterprises/ extended enterprises levels. Finally, a case study is given to demonstrate the developed framework and corresponding methodologies. © 2010 The Author(s).published_or_final_versionSpringer Open Choice, 21 Feb 201