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The node-to-surface formulation is widely used in contact simulations with finite elements because it is relatively easy to implement using different types of element discretizations. This approach, however, has a number of well-known drawbacks, including locking due to over-constraint when this formulation is used as a twopass method. Most studies on the node-to-surface contact formulation, however, have been conducted using solid elements and little has been done to investigate the effectiveness of this approach for beam or shell elements. In this paper we show that locking can also be observed with the node-to-surface contact formulation when applied to plate and flat shell elements even with a singlepass implementation with distinct master/slave designations, which is the standard solution to locking with solid elements. In our study, we use the quadrilateral four node flat shell element for thin (Kirchhoff-Love) plate and thick (Reissner-Mindlin) plate theory, both in their standard forms and with improved formulations such as the linked interpolation [1] and the Discrete Kirchhoff [2] elements for thick and thin plates, respectively. The Lagrange multiplier method is used to enforce the node-to-surface constraints for all elements. The results show clear locking when compared to those obtained using a conforming mesh configuration.

Atomic force microscopy (AFM) was used for visualization of a nano-oxidation technique performed on diamond-like carbon (DLC) thin film. Experiments of the nano-oxidation technique of the DLC thin film include those on nano-oxidation points and nano-oxidation lines. The feature sizes of the DLC thin film, including surface morphology, depth, and width, were explored after application of a nano-oxidation technique to the DLC thin film under different process parameters. A databank for process parameters and feature sizes of thin films was then established, and multiple regression analysis (MRA) and a back-propagation neural network (BPN) were used to carry out the algorithm. The algorithmic results are compared with the feature sizes acquired from experiments, thus obtaining a prediction model of the nano-oxidation technique of the DLC thin film. The comparative results show that the prediction accuracy of BPN is superior to that of MRA. When the BPN algorithm is used to predict nano-point machining, the mean absolute percentage errors (MAPE) of depth, left side, and right side are 8.02%, 9.68%, and 7.34%, respectively. When nano-line machining is being predicted, the MAPEs of depth, left side, and right side are 4.96%, 8.09%, and 6.77%, respectively. The obtained data can also be used to predict cross-sectional morphology in the DLC thin film treated with a nano-oxidation process.

Purpose: Traumatic optic neuropathy (TON) is a serious complication of head trauma with the incidence rate of 0.5%–5%. The aim of this study was to investigate the therapeutic efficacy of endoscopic decompression of the optic canal for optic nerve injuries. Methods: In this study, 11 patients treated in our hospital from January 2009 to January 2015 with the visual loss resulting from TON were retrospectively reviewed for preoperative vision, visual evoked potential (VEP) scan, surgical approach, postoperative visual acuity, complications, and follow-up results. Results: All these patients received endoscopic decompression of the optic canal. At the 3-month follow-up, the visual acuity improvement rate of the 11 patients was 45.5%. The vision acuity of 2 cases improved from hand movement to 0.08 and 0.3 after operation. Another patient's vision acuity returned to 0.05 compared to light sensation preoperatively. Two cases had finger counting before surgery but they had a vision acuity of 0.4 and light sensation respectively after surgery. However, the other 6 cases' vision did not improve after surgery. Conclusion: Endoscopic decompression of the optic canal is an effective way to cure TON. VEP could be used as an important reference for preoperative and prognosis evaluation. Operative time after trauma is only a relative condition that may affect the therapeutic effect of optic canal decompression. Poor results of this procedure may be related to the severity of the optic nerve injury.

Aluminum (Al) alloy 6061 is often used in engineering applications due to its high strength, excellent fracture toughness, and corrosion resistance. Lots of material removal or machining processes would induce some undesirable side effects like surface damages, fractures, and erosions. In this study, the surface defects in the workpieces caused by the electrical discharge machining process were eliminated with the plasma etching treatment. Meanwhile, the surface integrity and the fatigue properties of the workpiece improved significantly. Surface roughness, contact angle, and morphology were investigated by varying plasma etching parameters such as the etching power, oxygen gas flow, and the etching time. Furthermore, the optimum process conditions were evaluated using statistical analyses. The workpiece treated with the plasma etching had the smallest roughness of 12.2 µm, the largest contact angle of 92°, and 25% increase in the fatigue life. These experimental results indicated that the surface characteristics of the workpiece had a great influence on the fatigue life of electrical discharge machined Al alloy.

In this study, machining characteristics and mechanical properties of aluminum (Al) alloy 6061 were investigated with variations in discharge currents in electrical discharge machining. The machining characteristics included the electrode wear rate, material removal rate, and roughness. Mechanical properties such as the fatigue life and surface hardness were also discussed in this work. Experimental results showed that better fatigue property of the electrical discharge machined workpiece could be obtained when the discharge current was 15 A; meanwhile, the thickness of the white layer was around 19 µm. The relationship between the thickness of the white layer and the fatigue lifetime had a very strong positive correlation. Furthermore, the repeatability and stability of the machining process were explored by the quality control chart and Shewhart control chart. The results indicated that the electrical discharge machining process under optimum operating conditions was a well-controlled procedure and stable over time.

Discordant abundances of different immune cell subtypes is regarded to be an essential feature of tumour tissue. Direct studies in Prostate cancer (PC) of intratumoral immune heterogeneity characterized by immune cell subtype, are still lacking. Using the single sample gene set enrichment analysis (ssGSEA) algorithm, the abundance of 28 immune cells infiltration (ICI) were determined for PC. A NMF was performed to determine tumour‐sample clustering based on the abundance of ICI and PFS information. Hub genes of clusters were identified via weighted gene co‐expression network analysis (WGCNA). The multivariate dimensionality reduction analysis of hub genes expression matrix was carried out via principal component analysis (PCA) to obtain immune score (IS). We analysed the correlation between clustering, IS and clinical phenotype. We divided the 495 patients into clusterA (n = 193) and clusterB (n = 302) on the basis of ICI and PFS via NMF. The progression‐free survival (PFS) were better for clusterA than for clusterB (p < 0.001). Each immune cell subtypes was more abundant in clusterA than in clusterB (p < 0.001). The expression levels of CTAL‐4 and PD‐L1 were lower in clusterB than in clusterA (p < 0.001 and p = 0.006). We obtained 103 hub genes via WGCNA. In the training and validation cohorts, the prognosis of high IS group was worse than that of the low IS group (p < 0.05). IS had good predictive effect on 5‐year PFS. The expression of immune checkpoint genes was higher in the low IS group than in the high IS group (p < 0.01). Patients with low IS and receiving hormone therapy had better prognosis than other groups. The combination of IS and clinical characteristics including lymph node metastasis and gleason score can better differentiate patient outcomes than using it alone. IS was a practical algorithm to predict the prognosis of patients. Advanced PC patients with low IS may be more sensitive to hormone therapy. CXCL10, CXCL5, MMP1, CXCL12, CXCL11, CXCL2, STAT1, IL‐6 and TLR2 were hub genes, which may drive the homing of immune cells in tumours and promote immune cell differentiation. [ABSTRACT FROM AUTHOR]

This study intends to fabricate a small-size capacitive wireless transmission device. As to the design of electrode plates, the active electrode is designed in two ways, through row array and column array, and the area of an electrode plate is limited to below 20.25 cm 2 . Moreover, the passive electrode of row-array electrode plates is designed in three ways: general row array, window array, and rhombus array. As seen from the results of circuit simulation, the transmission efficiency of the capacitive wireless transmission device is as high as 0.7. In the actual circuit experiment, the electrode plate in the window-array design has the highest efficiency at 51%. In addition, the electrode plates in the window array and those in other arrays have higher stability and transmission efficiency. In the rotational angle dislocation experiment, the unit area current amount of the column-array electrode plates in the high coupling region is also smaller than that of the window-array electrode plates. However, the performance of column-array electrode plates reaches higher stability in the angle dislocation experiment, and its anti-angle dislocation is obviously higher than that of the electrode plates designed in the other three row arrays. Moreover, when the area of the column-array electrode plates is 22.25 cm 2 , the highest transmission distance is 22.5 mm.

In this study, an organic-inorganic semiconductor gas sensor was fabricated to detect ammonia gas. An inorganic semiconductor was a zinc oxide (ZnO) nanowire array produced by atomic layer deposition (ALD) while an organic material was a p-type semiconductor, poly(3-hexylthiophene) (P3HT). P3HT was suitable for the gas sensing application due to its high hole mobility, good stability, and good electrical conductivity. In this work, P3HT was coated on the zinc oxide nanowires by the spin coating to form an organic-inorganic heterogeneous interface of the gas sensor for detecting ammonia gas. The thicknesses of the P3HT were around 462 nm, 397 nm, and 277 nm when the speeds of the spin coating were 4000 rpm, 5000 rpm, and 6000 rpm, respectively. The electrical properties and sensing characteristics of the gas sensing device at room temperature were evaluated by Hall effect measurement and the sensitivity of detecting ammonia gas. The results of Hall effect measurement for the P3HT-ZnO nanowires semiconductor with 462 nm P3HT film showed that the carrier concentration and the mobility were 2.7 × 1019 cm−3 and 24.7 cm2∙V−1∙s−1 respectively. The gas sensing device prepared by the P3HT-ZnO nanowires semiconductor had better sensitivity than the device composed of the ZnO film and P3HT film. Additionally, this gas sensing device could reach a maximum sensitivity around 11.58 per ppm.

The aim of this research is to establish a set of employability indicators that capture the competency requirements and performance expectations that solar energy enterprises have of their employees. In the qualitative component of the study, 12 administrators and 32 engineers in the industry were interviewed, and meetings with focus groups were conducted to formulate a questionnaire for a survey of Taiwanese solar energy companies for the confirmation and prioritisation of the employability indicators. On the basis of the results of the quantitative component, an interpretational model relating competence, job performance, working attitude, and employability for solar corporation recruitment and training purposes as well as for school curricular development was developed. The interpretation model formulated effectively interprets the relationship between solar enterprises’ expectations and students’ employability. The research contributes a framework for the selection and cultivation of talent, as well as providing a basis for fundamental development of the solar engineering curriculum.

This study aims to develop professional competency indices and their subindices as needed by the solar energy industry, to establish a basis for development of the engineering education curriculum. The methodologies adopted by the study are literature analysis, expert advisories, and focus groups. The study focuses on the establishment of competency indices by experts at stock market-listed companies and then confirms these competencies with focus groups. The study found that the competencies required by the solar industry consist of knowledge, skills, and attitudes in the areas of materials development and applications, photovoltaic technology, cell manufacturing technology, biotechnology, chemical technology, power generation and electricity, process development and improvement, data collection and analysis, industry regulation, green energy beliefs, and working attitudes and values. The results of this study can be used as the basis for the cultivation, selection, and employment of industry professionals.

A miniature n-type semiconductor gas sensor was fabricated successfully using zinc aluminum oxide nanowire array and applied to sense oxygen. The present study provided a novel method to produce zinc aluminum alloy nanowire 80 nm in diameter by the vacuum die casting technique and then obtain zinc aluminum oxide nanowire array using the thermal oxidation technique. The gas sensing properties were evaluated through the change of the sensitivity. The factors influencing the sensitivity of the gas sensor, such as the alloy composition, operating temperature, and oxygen concentration, were investigated further. Experimental results indicated that the maximum sensitivity could be acquired when the weight percentage of aluminum was 5% in zinc aluminum alloy at the operating temperature of 200°C.

Zinc aluminum alloy nanowire was fabricated by the vacuum die casting. Zinc aluminum alloy was melted, injected into nanomold under a hydraulic pressure, and solidified as nanowire shape. Nanomold was prepared by etching aluminum sheet with a purity of 99.7 wt.% in oxalic acid solution. A nanochannel within nanomold had a pore diameter of 80 nm and a thickness of 40 μm. Microstructure and characteristic analysis of the alumina nanomold and zinc-aluminum nanowire were performed by scanning electron microscope, X-ray diffraction analysis, and energy dispersive X-ray spectroscopy. Zinc aluminum oxide nanowire array was produced using the thermal oxidation method and designed for the photoelectrode application.

This work determines the effect of compact TiO2 layers that are deposited onto fluorine-doped tin oxide (FTO), to improve the performance of dye-sensitized solar cells (DSSC). A series of compact TiO2 layers are prepared using radio frequency (rf) reactive magnetron sputtering. The films are characterized using X-ray diffraction (XRD), atomic force microscopy (AFM), scanning electron microscopy (SEM), and UV-Vis spectroscopy. The results show that when the Ar/O2/N2 flow rates are 36 : 18 : 9, the photo-induced decomposition of methylene blue and photo-induced hydrophilicity are enhanced. After annealing at 450°C in an atmosphere ambient for 30 min, the compact TiO2 layers exhibit higher optical transmittance. The XRD patterns for the TiO2 films for FTO/glass show a good crystalline structure and anatase (101) diffraction peaks, which demonstrate a higher crystallinity than the ITO/glass films. As a result of this increase in the short circuit photocurrent density, the open-circuit photovoltage, and the fill factor, the DSSC with the FTO/glass and Pt counter electrode demonstrates a solar conversion efficiency of 7.65%.

A two-step electrochemical anodization was used to form the anodic aluminum oxide (AAO) thin films with nanotube arrays of self-organized honeycomb structure. Al foil was anodized in 10% sulfuric acid (H2SO4) and 3% oxalic acid (H2C2O4) at 25°C at constant voltage of 40 V for 60 min for two times. Ethylene glycol (C2H6O2) was used as a solution and 0.3 M potassium iodide (KI) was used to improve the solution’s conductivity. Different electrolyte concentrations of Bi(NO3)3-5H2O, SbCl3, and TeCl4 were added into KI-C2H6O2 solution and the cyclic voltammetry experiment was used to find the reduced voltages of Bi3+, Sb3+, and Te4+ ions. The potentiostatic deposition and pulse electrodeposition (PED) processes were used to deposit the (Bi,Sb)2−xTe3+x-based materials. Field-emission scanning electron microscope and energy dispersive spectrometers were used to analyze the compositions of the deposited (Bi,Sb)2−xTe3+x-based materials. After finding the optimal deposition parameter of the PED process the AAO nanotube arrays were used as the templates to deposit the (Bi,Sb)2−xTe3+x-based thermoelectric nanowires.