Tribological behavior of plasma spray coatings for marine diesel engine piston ring and cylinder liner

High-temperature wear characteristics between plasma spray coated piston rings and cylinder liners were investigated to find the optimum combination of coating materials using the disc-on-plate reciprocating wear test in dry conditions. The disc and plate represented the piston ring and the cylinder liner, respectively. Coating materials studied were Cr₂O₃-NiCr, Cr₂O₃-NiCr-Mo, and Cr₃C₂-NiCr-Mo. Plasma spray conditions for the coating materials were established adjusting stand-off distance to obtain a coating with a porosity content of ∼5%. It was found that a dissimilar coating combination of Cr₂O₃-NiCr-Mo and Cr₃C₂-NiCr-Mo provided the best antiwear performance. The addition of molybdenum was found to be beneficial to improve the wear resistance of the coating. Hardness differences between mating surfaces were also important factors in determining the wear characteristics, so that it should be controlled below 300 in Vickers hardness under dry conditions. Adhesive wear accompanying with metal transfer was a dominant wear mechanism for dry conditions.     

Investigation on static routing and resource assignment of elastic all-optical switched intra-datacenter networks基于弹性全光交换技术的数据中心内网的静态路由和资源分配(RSIA)

In this paper, we explore the issue of static routing and spectrum/IT resource assignment (RSIA) of elastic all-optical switched intra-datacenter networks (intra-DCNs) by proposing anycast- and manycast-based integer linear programming (ILP) models. The objective is to jointly optimize the DCN resources, i.e., network transmission bandwidth and IT resources, under different situations. First, for given service-request matrices with unknown network transmission bandwidth and IT resources, we propose anycast and manycast ILP models to minimize the maximum numbers of required network and IT resources to accommodate all the service requests. For anycast RSIA issue, we proposed two different ILP models that are based on node-arc and link-path methods, respectively. Node-arc based manycast ILP model is also proposed for the first time to our knowledge. Second, for given network transmission bandwidth and IT resources and known service-request matrices, we propose node-arc based anycast ILP models to maximize the total number of successfully served service requests. To evaluate the efficiency of anycast and manycast models, all proposed ILP models are evaluated and compared with unicast ILP models. Simulation results show that anycast and manycast ILP models perform much better in efficiently using DCN resources and successfully accommodating more service requests when compared to unicast ILP models under the same network conditions.     

A study of roll‐printing technology for TFT‐LCD fabrication

Abstract— Recently, potential breakthrough technologies for low‐cost processing of TFT‐LCDs and new process developments for flexible‐display fabrication have been widely studied. A roll‐printing process using etch‐resist material as a replacement for photolithographic patterning was investigated. The characterization of the properties of patterns formed in roll printing, a method to fabricate cliché plates for fine patterns, and the design of a new formulation for resist printing ink is reported. The pattern position accuracy, which is one of the most important issues for the successful application of printing processes in display manufacturing was studied and how it can be improved by optimizing the blanket roll structure is explained. New design rules for the layout of the thin‐film‐transistor array was derived to improve the compatibility of roll printing. As a result, a prototype 15‐in.‐XGA TFT‐LCD panel was fabricated by using printing processes to replace all the photolithographic patterning steps conventionally used.     

Touch‐screen panel integrated into 12.1‐in. a‐Si:H TFT‐LCD

Abstract— A touch‐screen‐panel (TSP) embedded 12.1‐in. LCD employing a standard existing a‐Si:H TFT‐LCD process has been successfully developed. Compared with conventional external touch‐screen panels, which use additional components to detect touch events, the new internal TSP exhibits a clearer image and improved touch feeling, as well as increased sensing speed using discrete sensing lines to enable higher‐speed sensing functions including handwriting. The new internal digital switching TSP can be fabricated with low cost because it does not require any additional process steps compared to a standard a‐Si:H TFT‐LCD.     

High resolution X-ray phase contrast synchrotron imaging of normal and ligation damaged rat sciatic nerves

This study was performed to apply synchrotron radiation (SR) imaging to a neuropathologic evaluation technique after treatment of peripheral nerve blocks. A phase contrast synchrotron images of normal and ligation damaged rat sciatic nerve were obtained with an 8 KeV monochromatic beam and 20-mum thick CsI(TI) scintillation crystal. The visual image was magnified using a 20x microscope objective and captured using an analog CCD camera. Obtained images were compared with conventional light microscopic findings from the same nerve samples. By using an edge enhancement effect of phase const with SR, we could easily discriminate each nerve fiber and identify the arrangement of nerve fibers within a whole thickness (about 1 mm in diameter) of peripheral nerve without sectioning and fixation. The composite SR image of a ligation damaged rat sciatic nerve sample showed that the response to nerve injury was different on each side of the site of injury. The SR image of damaged distal lesion showed destruction of neural microarchitecture and typical extensive Wallerian degeneration of nerve fibers as clearly as histologic image. We could get very detailed morphologic data for Wallerian degeneration of nerve fibers by using the SR imaging technique. We believe that the phase contrast synchrotron imaging has great potential as an imaging tool in the bioscience and medical science.     

Feature matching and instance reweighting with transfer learning for human activity recognition using smartphone

Human activity recognition using smartphone has been attracting great interest. Since collecting large amount of labeled data is expensive and time-consuming for conventional machine learning techniques, transfer learning techniques have been proposed for activity recognition. However, existing transfer learning techniques typically rely on feature matching based on global domain shift and lack considering the intra-class knowledge transfer. In this paper, a novel transfer learning technique is proposed for cross-domain activity recognition, which can properly integrate feature matching and instance reweighting across the source and target domain in principled dimensionality reduction. The experiments using three real datasets demonstrate that the proposed scheme can achieve much higher precision (92%), recall (91%), and F1-score (92%), in comparison with the existing schemes.

     

Effect of stents coated with a combination of sirolimus and alpha-lipoic acid in a porcine coronary restenosis model

The aim of this study was to evaluate antiproliferative sirolimus- and antioxidative alpha-lipoic acid (ALA)-eluting stents using biodegradable polymer [poly-l-lactic acid (PLA)] in a porcine coronary overstretch restenosis model. Forty coronary arteries of 20 pigs were randomized into four groups in which the coronary arteries had a bare metal stent (BMS, n = 10), ALA-eluting stent with PLA (AES, n = 10), sirolimus-eluting stent with PLA (SES, n = 10), or sirolimus- and ALA-eluting stent with PLA (SAS, n = 10). A histopathological analysis was performed 28 days after the stenting. The ALA and sirolimus released slowly over 30 days. There were no significant differences between groups in the injury or inflammation score; however, there were significant differences in the percent area of stenosis (56.2 ± 11.78 % in BMS vs. 51.5 ± 12.20 % in AES vs. 34.7 ± 7.23 % in SES vs. 28.7 ± 7.30 % in SAS, P < 0.0001) and fibrin score [1.0 (range 1.0–1.0) in BMS vs. 1.0 (range 1.0–1.0) in AES vs. 2.0 (range 2.0–2.0) in SES vs. 2.0 (range 2.0–2.0) in SAS, P < 0.0001] between the four groups. The percent area of stenosis based on micro-computed tomography corresponded with the restenosis rates based on histopathological stenosis in different proportions in the four groups (54.8 ± 7.88 % in BMS vs. 50.4 ± 14.87 % in AES vs. 34.5 ± 7.22 % in SES vs. 28.9 ± 7.22 % in SAS, P < 0.05). SAS showed a better neointimal inhibitory effect than BMS, AES, and SES at 1 month after stenting in a porcine coronary restenosis model. Therefore, SAS with PLA can be a useful drug combination for coronary stent coating to suppress neointimal hyperplasia.