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To investigate alteration of outer nuclear layer (ONL) and choroidal vascularity index (CVI) in different status of central serous chorioretinopathy (CSC). A retrospective review of 65 CSC eyes with subretinal fluid (manifest CSC) and 40 control eyes was conducted in a single tertiary university hospital. Differences in best-corrected visual acuity (BCVA), ONL, and CVI were compared. CVI was assessed both in the entire choroid (CVI-EC) and around the 1500 μm leakage area (CVI-1500). Measurements were repeated after the subretinal fluid resorption (quiescent CSC), and compared. CSC eyes showed worse BCVA, thinner ONL and greater CVI than controls. Quiescent CSC showed a recovery of ONL compared to the manifest CSC, along with the BCVA improvement. The resolution of the CSC revealed a decrease across all three choroidal areas (total, stromal and luminal), with a more pronounced reduction in the stromal than in the luminal choroidal area, leading to an increase in the CVI. This phenomenon was shown in both CVI-EC and CVI-1500. Conclusively, ONL thickness can be used as a quantitative biomarker for photoreceptor function in CSC. Increased CVI may reflect a disease activity. The stromal choroidal area is particularly sensitive in illustrating leakage from the choroidal vasculature. [ABSTRACT FROM AUTHOR]

To investigate the changes in outer nuclear layer (ONL) thickness during anti-vascular endothelial growth factor (VEGF) treatment in type 1 choroidal neovascularization (CNV) and its impact on vision. Type 1 CNV eyes (n = 94) were retrospectively compared to normal control eyes (n = 35). Along with best-corrected visual acuity (BCVA), the location of CNV, foveal ONL thickness, and subretinal fluid height were measured using optical coherence tomography (OCT) and analyzed. Visual outcome and OCT biomarkers were compared. As a result, the CNV group had thinner foveal ONL and worse BCVA compared to the control group. ONL thickness recovered partially along with visual improvement following 3 monthly initial loading doses of aflibercept injections, and it correlated with the final BCVA during the 1-year follow-up. Eyes achieved foveal ONL recovery over + 10 µm had lower subfoveal CNV (45.5%) and showed better visual outcomes than eyes with stationary ONL or suboptimal ONL recovery (76.0%, p = 0.012). In conclusion, type 1 CNV eyes that recovered foveal ONL thickness at initial loading of anti-VEGF demonstrated good final visual outcome during the 1-year follow-up. Monitoring the foveal ONL thickness during early anti-VEGF treatment can give information about the visual outcomes in type 1 CNV. [ABSTRACT FROM AUTHOR]

Support vector machine (SVM) is a popular supervised machine learning technique extensively applied to various real-life applications. A weakness of SVM, though, is that its efficiency rapidly decreases as the size of training dataset increases. This issue is more challenging for the devices and applications of IoT where the computing resource is quite constrained. As a result, numerous schemes have been proposed to decrease the training time of SVM, especially for the large-scale dataset. In this paper, a survey on the state-of-the-art methods for reducing the number of training data points and increasing the speed of SVM is presented. The existing methods are categorized into five types based on the approach employed for data reduction process, namely clustering-based, geometrical, distance-based, random sampling, and evolutionary methods. The key characteristics of the schemes are reviewed and compared against six practical benchmarks. This survey will be useful to select an appropriate method for the given target problem and develop a new approach for improving the performance of SVM dealing with the large-scale dataset. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Aluminium (Al)-based alloys have attracted as promising materials for structural applications using metal 3D printing due to their excellent specific mechanical strength, formability, and durability. In this study, highly flowable coarse AlSi10Mg powders with average diameter of 65 µm were prepared and then they were additively manufactured by using the selective laser melting (SLM) process. The relative densities exceeding 99% were consistently obtained from the samples fabricated at the scan speed of 1000–2000 mm·s−1 in the range of laser power from 350 to 390 W. The tensile strengths and elongation of all the samples were characterised. Furthermore, Al alloy processed by coarse AlSi10Mg powders does not show a big change in strength values compared to those fabricated by fine AlSi10Mg powders with 45 µm in diameter. Thus, these results clearly show that the developed coarse AlSi10Mg powders can be effectively utilised for the SLM process. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) building information modeling (BIM) models of alignment-based civil infrastructures such as roads, railways, and tunnels are built as an integrated surface model for each planned linear segment. In the multidimensional (nD) form of BIM, the model can be linked with information such as quantity, schedule, and cost. Furthermore, even if the nD form of BIM is fulfilled, the design and linked information are changed; subsequently, not only must the BIM model be re-created but each link to the information must be updated. In this study, a system was developed to partition the 3D BIM model according to the level required by the user. A partition interval allows the user to input the start and end points or to set a constant interval unit on the basis of the design baseline. In addition, each segment of the partitioned BIM model can be equipped with information such as earthwork volume (cut and fill), cost, and schedule. Finally, a case study was conducted using a road BIM model to verify the developed system. [ABSTRACT FROM AUTHOR]

Purpose. To investigate the associations between hyperreflective foci (HRF) on spectral-domain optical coherence tomography (SD-OCT) and early recurrence of macular edema after intravitreal dexamethasone (DEX) implantation in eyes with refractory diabetic macular edema (DME) to bevacizumab. Methods. Medical records of patients with refractory DME to bevacizumab, who underwent intravitreal DEX implantation and 12-month follow-up, were reviewed. Eyes in which central subfield thickness (CST) increased over 50 μm at 3 months compared with the first month after intravitreal DEX implantation were categorized into the early recurrence group, and the others were categorized into the late recurrence group. Best-corrected visual acuity (BCVA), CST, and number of HRF on SD-OCT were analyzed. Results. Twenty-nine eyes of 26 patients (16 eyes in the early recurrence group and 13 eyes in the late recurrence group) were included in this study. The numbers of HRF in entire retina, inner retina, and outer retina at baseline in the early recurrence group (11.38 ± 3.07 in entire retina, 5.44 ± 1.50 in inner retina, 5.94 ± 2.74 in outer retina) were significantly greater than those in the late recurrence group (7.54 ± 3.60 in entire retina, p=0.006; 4.08 ± 1.70 in inner retina, p=0.034; 3.46 ± 2.30 in outer retina, p=0.013). Multivariate logistic regression analysis showed that a higher number of HRF increased the risk of early recurrence after intravitreal DEX implantation (odds ratio in entire retina: 1.518, p=0.012; odds ratio in inner retina: 2.058, p=0.027; odds ratio in outer retina: 1.610, p=0.029). Conclusions. Higher baseline numbers of HRF on SD-OCT may be a predictive indicator of early recurrence of macular edema after intravitreal DEX implantation for DME. [ABSTRACT FROM AUTHOR]

Support Vector Machine (SVM) is an efficient machine learning technique applicable to various classification problems due to its robustness. However, its time complexity grows dramatically as the number of training data increases, which makes SVM impractical for large-scale datasets. In this paper, a novel Parallel Hyperplane (PH) scheme is introduced which efficiently omits redundant training data with SVM. In the proposed scheme the PHs are recursively formed while the clusters of data points outside the PHs are removed at each repetition. Computer simulation reveals that the proposed scheme greatly reduces the training time compared to the existing clustering-based reduction scheme and SMO scheme, while allowing the accuracy of classification as high as no data reduction scheme. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlight • Snowman-shaped Ni/Al particles are synthesized by removing Al oxide and plating Ni. • The Ni nanoparticle is only coated on the surface oxide removed region of Al surface. • The SNA particle shows high exothermic enthalpy energy during thermal oxidation. • The directly bonded Ni/Al interface produces a rapid and much intermetallic compounds. Abstract Nickel-nanoparticle-attached aluminum (Ni/Al) particles are synthesized by plating Ni onto Al particles with the surface oxide partly removed. The microstructure of the synthesized Ni/Al particles resembles a child's snowman, with an approximately 200 nm spherical Ni nanoparticle bonded onto the surface of an Al particle about 800 nm in size. Particularly, the surface oxide is rarely observed at the Ni/Al interfaces unlike uncoated surface of the Al powder. Due to these microstructural characteristics, it was clearly noted that a self-propagating high-temperature synthesis (SHS) reaction of the snowman-shaped Ni/Al (SNA) particles occurs more actively compared to that which occurs when simply mixing particles of Ni and Al in the temperature range of 720–900 K. The formation of intermetallic compounds of NiAl or NiAl 3 is confirmed in a comparison of XPS results after both samples were oxidized at 773 K. The exothermic enthalpy energy, 8,850 Jg−1 of SNA particles represents 118% of the value of 7,580 Jg−1 for the mixed particles. These results indicate that SNA particles are promising as advanced reactive materials when used in conjunction with an efficient SHS reaction. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • EOG-dispersed Bi 0.4 Sb 1.6 Te 3 thick film was fabricated by using paste-based process. • EOGs electrically connect the separated BST grains via interfacial bonding. • The EOGs in the film provides rapid transporting pathways for carriers. • The thermopower value of BST thick film was improved by addition of the EOG. Abstract Edge-oxidized graphene-dispersed Bi 0.4 Sb 1.6 Te 3 (EOG/BST) thick films are fabricated by the hand-printing of EOG/BST paste followed by a heat-treatment process. Fabricated EOG/BST thick films are approximately 200 μm thick, and the EOGs in the film are dispersed rather than agglomerated but also appear to connect the separated BST grains. A 2 wt% EOG/BST thick film shows a maximum thermopower of 0.00206 W/mK2, which is approximately 1.7 times higher than the output of 0.00133 W/mK2 of BST film without EOG. The improved thermopower stems from the EOG, which provides rapid carrier-transport and an increase in the electrical conductivity of the BST film. It has been found that the edge-surface of EOG is chemically bonded with Bi, Te and Sb via interfacial oxygen atoms and the perfect graphite (sp2) structure of the EOG facilitates rapid movement of the carriers. The carrier mobility of 2 wt% EOG/BST film sample was improved by about 1.75 times without sacrificing the carrier density compared to that of BST film. These results indicate a promising means of using EOG to enhance the electrical properties of thermoelectric thick films, which can be utilized in active coolers and in wearable power generators. [ABSTRACT FROM AUTHOR]

• The PTFE coated Al (PTFE/Al) powders without surface oxide were synthesized with different sizes. • Synergistically increased exothermic energy (ΔH) was achieved from the smallest PTFE/Al powders. • Simultaneous control of PTFE coating and powder size opens novel route to tailor energetic properties. Polytetrafluoroethylene (PTFE)-coated aluminum (PTFE/Al) powder was synthesized to evaluate its exothermic reactivity with the reduction in Al powder size. The exothermic enthalpy energies of uncoated Al powders clearly increase as the particle size decreases from 30 to 5 μm. Thus, the PTFE/Al (5 μm) powder exhibited the highest exothermic enthalpy energy of 4300 J/g, which is approximately two times higher than that of uncoated Al (5 μm) and PTFE/Al (30 μm) powders. The findings clarify that the combination of powder size reduction and PTFE coating results in both a considerable enhancement of exothermic reactivity and tailorable enthalpy energy values. [ABSTRACT FROM AUTHOR]

Here, we report the persistent photoconductance (PPC) and transient photo-response characteristics of photochemically activated and thermally annealed indium‑gallium‑zinc-oxide (IGZO) thin-film transistors (TFTs). From various analyses on the time-variant photo-current change in IGZO TFTs, it was found that photochemically activated IGZO TFTs exhibited significantly weak PPC behavior and rapid photo-decaying characteristics compared to thermally annealed IGZO TFTs. It is claimed that such behaviors of photochemically activated IGZO TFTs are due to the low activation energy for the neutralization of ionized oxygen vacancies, which can be beneficial in achieving highly photo-stable electronic devices. Furthermore, we report the influence of pulsed gate bias on the photo-decaying characteristics of photochemically activated and thermally annealed IGZO TFTs. [ABSTRACT FROM AUTHOR]

As flash memory becomes popular, flash memory-based solid-state drive (SSD) has been the major storage device. SSD has numerous merits such as high I/O speed, low energy consumption, strong shock resistance and small form factor. Meanwhile, some shortcomings still exist including erase-before-write and different cost for read, write and erase operation. Aiming at efficient buffer management of SSD, this paper proposes a novel approach based on particle swarm optimization (PSO) algorithm. The PSO algorithm is used to estimate the Predict Hot Fitness value of each logical page in the buffer to correctly identify them either as hot or cold by properly reflecting the spatial and temporal locality. The pages predicted as hot are kept in the buffer to maximize the hit ratio and utilization of the SSD buffer. Simulation with real workload shows that the proposed scheme significantly outperforms the representative SSD buffer management schemes in terms of hit ratio and throughput. [ABSTRACT FROM AUTHOR]

Nanodiamond-dispersed Bi 2 Te 2.7 Se 0.3 (ND/BTSe) matrix composites were fabricated by a high energy ball milling followed by spark plasma sintering process. The fabricated ND/BTSe composites show that ND powders with 5 nm in size are dispersed in the BTSe matrix grain rather than agglomerated at the grain boundary. It was found that atomically disordered-lattice structure present nearby the newly formed ND/BTSe interfaces. This interfacial region artificially formed by addition of ND powders plays a role as atomic-scaled defects increasing electron concentration. Electric conductivities of all the ND/BTSe composites show significantly increased values compared to that of pure BTSe in the temperature range from 298 K to 473 K. However, total thermal conductivity of the composites exhibit higher values than the BTSe due to superior electric conductivity even though active lattice phonon scattering at the interfaces affect lowering thermal conductivity. The maximum ZT, 0.97 was obtained from 0.5vol%ND/BTSe composite at 473 K and enhancement in ZT values was clearly revealed above 348 K. Therefore, these results elucidate that addition of ND powders into n-type BTSe matrix is promising method to improve thermoelectric performances. [ABSTRACT FROM AUTHOR]

Nickel (Ni) materials with a thickness of a few hundred nm were homogeneously coated on the surfaces of aluminum (Al) powders by an electroless plating process. The Ni-coated Al powders show characteristic interfacial structures mixed of Ni, Al and O instead of densely packed Al oxide at the surface. The explosion test of the Ni-coated Al powders utilizing flame ignition showed that the powders had a 3.6 times enhanced pressurization rate of 405 kPa/ms compared to 111 kPa/ms of uncoated Al powders. It was found that this is due to a feasible diffusion of oxygen atoms into the Al powders through the thin and rough interfacial layers present at the Ni/Al interface. These results clearly indicate that nano-sized Ni film introduced instead of surface oxide acts as a very profitable layer to achieve efficient combustion behaviors by a rapid oxidation of Al powders. [ABSTRACT FROM AUTHOR]

A fluorescent dopamine–naphthalimide–dipicolylamine (DPA) was synthesized as a sensing receptor for Zn 2+ . Naphthalimide-DPA ( 2 ) was immobilized onto the surface of iron oxide nanoparticle to prepare a hybrid nanomagnet 1-Fe 3 O 4 . Naphthalimide–DPA ( 2 ) and 1-Fe 3 O 4 were observed to bind with Zn 2+ , leading to significant increase in fluorescence intensity at 527 nm. The fluorescence increases of 2 (10 μM) and 1-Fe 3 O 4 (0.33 wt%) by addition of Zn 2+ were linear over the [Zn 2+ ] range of 0–7 μM and 0–20 μM, respectively. These fluorescence changes were highly selective for Zn 2+ , which were readily monitored even in the presence of other competitive cations. In particular, 1-Fe 3 O 4 exhibited an excellent limit of detection determined to be 0.0345 ppb. Furthermore, this system was found to be suitable for detecting Zn 2+ in a wide pH range of 3–11 and could be reused with the addition of ethylenediaminetetraacetic acid (EDTA). Moreover, nanomagnet 1-Fe 3 O 4 was employed for the selective detection and removal of Zn 2+ from a soil sample. These results confirm that the use of 1-Fe 3 O 4 is a novel and simple method for detecting Zn 2+ in environmental samples. [ABSTRACT FROM AUTHOR]

Bee pollen collected by honeybees, which is in powdered form, is a good nutritional supplement. Nitrofuran antibiotics are assumed not to be present in bee pollen, which is important as the level of antibiotics in bee pollen is strongly regulated in many countries. A liquid chromatography–tandem mass spectrometry (LC–MS/MS) method to detect nitrofurans in honey has been developed, but this method is not suitable for bee pollen because of it being in powdered form. During preparation of bee pollen samples, the dispersal of powder particles in an aqueous solution often makes them susceptible to forming an emulsion with solvent components such as hexane and ethyl acetate. This may reduce the reproducibility and sensitivity of analyses of nitrofuran levels in bee pollen. Therefore, we attempted to optimize the sample preparation conditions to detect nitrofurans in bee pollen by determining three nitrofuran residues, namely, 3-amino-2-oxazolidinone (AOZ), 3-amino-5-methyl-morpholino-2-oxazolidinone (AMOZ), and 1-aminohydantoin (AHD), using LC–MS/MS. The optimized method prevented the formation of powder-induced emulsion. To verify the reproducibility and sensitivity of this method, it was validated using nitrofuran-free bee pollen spiked with analytes with different side chains at 1.0, 2.0, and 5.0 μg kg −1 . The accuracy levels were 94.1%–104.0% and the coefficients of variation were less than 12%. The limits of detection for AOZ, AMOZ, and AHD were 0.18, 0.25, and 0.30 μg kg −1 , respectively, while their limits of quantitation were 0.59, 0.83, and 1.00 μg kg −1 . The LC–MS/MS method developed to analyze nitrofuran in bee pollen should contribute to the quality control of bee pollen and food safety. [ABSTRACT FROM AUTHOR]

Polytetrafluoroethylene (PTFE) films were homogeneously coated onto aluminum powders. The synthesized PTFE-coated aluminum (PTFE/Al) powders showed a microstructure of spherical Al powders covered with PTFE film of a few hundreds of nm in thickness. The PTFE/Al powders showed significantly increased gravimetric energy of 4.80 kJ g −1 compared to the value of 0.88 kJ g −1 for pure Al powders during oxidation in a temperature range of 25–1450 °C. It was found that the PTFE/Al interface mixed with oxygen and fluorine atoms provided a vigorous oxidation of the Al powders. These results clearly confirm that the PTFE layer acts as a protective layer and an oxidation helper. [ABSTRACT FROM AUTHOR]

Carbon nanotube/bismuth-selenium-tellurium composites were fabricated by consolidating CNT/Bi2(Se,Te)3 composite powders prepared from a polyol-reduction process. The synthesized composite powders exhibit CNTs homogeneously dispersed among Bi2(Se,Te)3 matrix nanopowders of 300 nm in size. The powders were densified into a CNT/Bi2(Se,Te)3 composite in which CNTs were randomly dispersed in the matrix through spark plasma sintering process. The effect of an addition of Se on the dimensionless figure-of-merit (ZT) of the composite was clearly shown in 3 vol.% CNT/Bi2(Se,Te)3 composite as compared to CNT/Bi2Te3 composite throughout the temperature range of 298 to 473 K. These results imply that matrix modifications such as an addition of Se as well as the incorporation of CNTs into bismuth telluride thermoelectric materials is a promising means of achieving synergistic enhancement of the thermoelectric performance levels of these materials. [ABSTRACT FROM AUTHOR]

Mori Cortex Radicis ( MCR), the dried root bark of Morus alba L., is a well-known traditional herbal medicine. While several studies have examined the components and bioactivities of MCR, this study describes the development of a method for the simultaneous quantitative evaluation of two marker compounds for quality control and classification of MCR samples. Two marker compounds of MCR, kuwanon G and morusin, were separated and quantified using high-performance liquid chromatography ( HPLC) on an Optimapak C18 column (4.6 × 250 mm, 5 µm). The compounds were eluted with a mobile phase of water and methanol under gradient conditions (0 min at 15% B, 5 min at 70% B, 30 min at 100% B) at a flow rate of 1.0 mL/min and a detection wavelength of 270 nm. The method was validated with respect to linearity, accuracy, precision, and recovery. The results satisfied the guidelines set by the Ministry of Food and Drug Safety ( MFDS), Korea. The validated method was applied to the quantification of the two marker compounds in 81 samples (65 MCRs, 16 similar crude drugs) collected from various regions of Korea and China. Using a linear regression method, content criteria were established in accordance with the quantitative results obtained with the two marker compounds of MCR. Therefore, the developed HPLC method is suitable for quality control and classification of MCR samples according to harvesting country. [ABSTRACT FROM AUTHOR]

We investigated the irreversible demagnetization of a permanent-magnet (PM) brushless dc motor under an interturn fault condition. For the transient analysis, we developed a finite-element method-based demagnetization algorithm in the operating state, taking into account the circulating current flowing in the shorted turns and the freewheeling current flowing in the diode. We analyzed the magnetic distribution property, input current, circulating current, and demagnetization characteristic of the PM using this algorithm. The analysis results from the demagnetization algorithm were verified by dynamic fault experiments. [ABSTRACT FROM AUTHOR]

In this study, we propose a modified polar mapping classifier (M-PMC) with an efficient preprocessing scheme to classify synthetic aperture radar (SAR) targets from the public release database for moving and stationary target acquisition and recognition. M-PMC is evaluated under various SAR extended operating conditions (EOCs), which are designed to reflect real-world battlefield scenarios. Experimental outcomes from various EOCs show that M-PMC has good generalization capabilities and outperforms conventional classifiers. [ABSTRACT FROM AUTHOR]

In this paper, the characteristics of brushless dc (BLDC) motors were compared and analyzed according to the types and control methods under the inter-turn fault (ITF) condition. The shorted windings produced by the ITF were modeled by the winding function theory (WFT) based on the distributed constant circuit method. We also introduced the inductance calculated by the WFT to the voltage equation and analyzed the effect of the ITF using the characteristics of the input and output parameters. The increase rate of torque ripple, increase rate of input current, and the circulating current of the surface permanent-magnet (PM) and interior PM motors under healthy and ITF conditions were compared to determine which motor type is more efficient in preventing the ITF. We also analyzed the fault characteristics by applying the advanced angle control. In this paper, the analysis results are validated by the finite-element method and experiments. [ABSTRACT FROM PUBLISHER]

Highlights: [•] Fucoidan is an efficient inhibitor of α-amylase and α-glucosidase. [•] The inhibitory activity varied among harvesting period and the targeted enzyme. [•] Fucoidan from A. nodosum inhibited both enzymes. [•] Fucoidans from F. vesiculosus inhibited only α-glucosidase. [•] Each species has its own optimal period of harvesting for enzymatic inhibition. [Copyright &y& Elsevier]

Interturn faults (ITFs) cause significant changes in the electrical and magnetic characteristics of motors. In particular, ITFs can be the cause of serious distortions in the magnetic field of an air gap. Therefore, we develop a system matrix with an ITF for FEM simulation, which considers the nonlinearity of the ITF. Using the analysis of the magnetic characteristics of the detection coil from the FEM results, a circuit that employs the proposed diagnosis algorithm is shown to detect the phase and the location of a fault. [ABSTRACT FROM AUTHOR]

This paper proposes a new design of SPOKE-type PM brushless direct current (BLDC) motor without using neodymium PM (Nd-PM). The proposed model has an improved output characteristic as it uses the properties of the magnetic flux effect of the SPOKE-type motor with an additional pushing assistant magnet and subassistant magnet in the shape of spoke. In this paper, ferrite PM (Fe-PM) is used instead of Nd-PM. First, the air-gap flux density and backelectromotive force (BEMF) are obtained based on the field model. Second, the analytical expressions of magnet field strength and magnet flux density are obtained in the air gap produced by Fe-PM. The developed analytical model is obtained by solving the magnetic scalar potential. Finally, the air-gap field distribution and BEMF of SPOKE-type motor are analyzed. The analysis works for internal rotor motor topologies. This paper validates results of the analytical model by finite-element analysis for wing-shaped SPOKE-type BLDC motors. [ABSTRACT FROM AUTHOR]

This paper investigates the dynamic demagnetization characteristics of an interior permanent magnet (PM) brushless dc motor with a stator turn fault (STF). A new algorithm, which is a finite-element method combined with a line voltage equation of the motor, is developed to analyze demagnetization under dynamic and transient states and considers an STF. The input current, circulating current, magnetic distribution characteristic, and operating property of the PM, including the irreversible demagnetization in the fault state, are analyzed using this algorithm by considering the magnetic saturation effect. The feasibility of the proposed method confirmed from the analysis results is verified via an experiment. Through this fault analysis, we can accurately check the fault phenomena and healthiness of a PM motor against the demagnetization fault for fault prevention. [ABSTRACT FROM AUTHOR]

Novel nitrogen-doped graphene nanoribbons (GNR-Ns) are synthesized by the coupling reaction between a pyrazine (or benzene) derivative and naphthalene followed by cyclodehydrogenation. The amount of nitrogen doping in the GNR-Ns is controlled by changing the monomer feed ratio of pyrazine to benzene for polymerization. The electron mobility of the GNR-Ns increases while the hole mobility decreases, as the amount of nitrogen doping in the GNR increases, indicating that the charge-transport behavior of GNRs is changed from ambipolar to an n-type semiconductor. The threshold voltage of the GNR-Ns also shifts from 20 to −6 V as the amount of nitrogen doping increases. [ABSTRACT FROM AUTHOR]

Abstract: Novel precursor polymers containing phenylene, naphthalene and anthracene units were synthesized for fabrication of graphene nanoribbons (GNRs) by the Suzuki coupling reaction between dibrominated monomers and diboronic ester monomers. The precursor polymers were converted into GNRs by intramolecular cyclodehydrogenation using FeCl3 as a catalyst. The degree of cyclodehydrogenation was determined by analysis of nuclear magnetic resonance spectra. All GNR films show ambipolar charge transport behavior in thin-film transistor (TFT). The GNR film prepared from anthracene-based polymer exhibits the highest TFT performance due to its longer conjugation length and larger width of nanoribbon than GNRs prepared from phenylene and naphthalene-based polymers. [Copyright &y& Elsevier]

Currently, sensor networks are widely used in various fields. Here secure operations are required for critical applications since the damages are significant if the network is compromised or disrupted. For the security of wireless sensor network, the earlier schemes typically employ asymmetric cryptography. These schemes are, however, often unsuitable for wireless sensor network due to the limited computational power and energy of the sensor nodes. To address this issue, various approaches have been developed, and the random key predistribution approach has been recognized as an effective approach. One shortcoming, however, is that a common key is not guaranteed to be found between any two nodes wanting to communicate. This paper proposes a new robust key predistribution scheme solving this problem, with which the security is not compromised even though the data exchanged between the nodes are tapped by an adversary. This is achieved by using the keys assigned based on the notion of eigenvalue and eigenvector of a square matrix of a pool of keys. Mathematical analysis and computer simulation reveal that the proposed scheme significantly reduces the overhead required for secure connectivity and energy consumption of sensor nodes compared to the existing approaches. [ABSTRACT FROM AUTHOR]

Objective: To assess the relationship between mycoplasma infection and human infertility, we determined the concordance of Ureaplasma urealyticum (UU) and Mycoplasma hominis (MH) detection in infertile and fertile couples, and assessed semen parameters in both groups. Methods: Fifty infertile couples without a female factor attending a fertility clinic and 48 fertile couples were randomly screened for UU and MH. The concordance between partners was compared between the fertile and infertile groups. Semen and endocervical specimens were evaluated using the commercially available Mycofast Evolution2 test. Results: UU was detected in 24 semen specimens (48%) from the infertile men, in 12 specimens from fertile men (25%), in 20 endocervical specimens from infertile women (40%), and 11 from fertile women (22.9%). UU was detected higher in infertile men than in fertile men (P = .022). The concordance of UU was higher in infertile couples (32%) than in fertile couples (12.5%, P = .022). The concordance of MH between male and female partners in the 2 groups did not differ significantly. The mean values of total motility, progressive motility, normal morphology, vitality, and total motile sperm count were significantly lower in sperm from infertile men than from fertile men. Progressive motility and vitality were significantly lower in UU-positive men than in men without UU, and low total motility and total motile sperm count were significantly related to the presence of MH. Conclusion: Clinicians should consider the roles of UU and MH in infertility and routinely screen infertile couples for the presence of these mycoplasma species. [ABSTRACT FROM AUTHOR]

It is shown that if the bilinear stress-separation law of the cohesive crack model is identified from the complete softening load-deflection curve of a notched human bone specimen of only one size, the problem is ill-conditioned and the result is non-unique. The same measured load-deflection curve can be fitted with values of initial fracture energy and tensile strength differing, respectively, by up to 100 and 72.4 % (of the lower value). The material parameters, however, give very different load-deflection curves when the specimen is scaled up or down significantly. This implies that the aforementioned non-uniqueness could be avoided by testing human bone specimens of different sizes. To demonstrate it, tests of notched bovine bone beams of sizes in the ratio of 1: $$\sqrt{6}$$:6 are conducted. To minimize random scatter, all the specimens are cut from one and the same bovine bone, even though this limits the number of specimens to 8. A strong size effect is found, but an anomaly in the size effect data trend is obtained, probably due to random scatter and too small a number of specimens. Further it is shown that the optimum range of size effect testing based on Bažant's size effect law approximately coincides with the size range of beams that can be cut from one bovine bone. By size effect fitting of previously published data on human bone, it is shown that the optimum size range calls for beam depths under 10 mm, which is too small for the standard equipment of mechanics of materials labs and would require a special miniaturized precision equipment. [ABSTRACT FROM AUTHOR]

This paper proposes a new design of a SPOKE-type permanent magnet brushless direct current (BLDC) motor by using pushing magnet. A numerical analysis is developed to calculate the maximum value of air-gap flux density. First, the analytical model of the SPOKE-type motor was established, and Laplace equations of magnetic scalar potential and a series of boundary conditions were given. Then, the analytical expressions of magnet field strength and magnet flux density were obtained in the air gap produced by ferrite permanent magnets. The developed analytical model was obtained by solving the magnetic scalar potential. Finally, the air-gap field distribution and back-electromotive force of spoke type machine was analyzed. The analysis works for internal rotor motor topologies, and either radial or parallel magnetized permanent magnets. This paper validates results of the analytical model by finite-element analysis as well as with the experimental analysis for SPOKE-type BLDC motors. [ABSTRACT FROM AUTHOR]

Abstract: CNT/Bi2Te3 composites were prepared from composite powders in which CNTs were implanted in the Bi2Te3 matrix powders by a novel chemical route. It was found that the fabricated composite had a microstructure of a homogeneous dispersion of CNTs in the Bi2Te3 matrix due to interfacial bonding agents of oxygen atoms attaching to the surface of CNTs. The dimensionless figure of merit (ZT) of the composite shows significantly increased values compared to those of pure binary Bi2Te3 in the temperature range of 298–498K and a maximum ZT of 0.85 was obtained at 473K. It is considered that the improved thermoelectric performance of the composite mainly originated from thermal conductivity that was reduced by active phonon-scattering at the CNT/Bi2Te3 interface. [Copyright &y& Elsevier]

Abstract: We investigated the pharmacokinetic profile of (R)- and (S)-zaltoprofen (ZPF) in rats using rapid and selective liquid chromatography with solid-phase extraction (SPE). The ZPF enantiomers were extracted from a small volume of plasma (0.2mL) by means of SPE using cartridges and were analyzed on a Chiralcel OJ-H (4.6mm×150mm, 5μm) column with ultraviolet detection at 244nm. The lower limit of quantification of the ZPF enantiomers in plasma was 0.1μg/mL. The validated method was successfully applied to chiral pharmacokinetic studies of oral administration of racemic ZPF to rats. (S)-ZPF showed significantly higher AUC, T max, and C max and a longer half-life than (R)-ZPF, indicating higher bioavailability of the (S)-isomer. A total of 8 samples (about 12% of the total number of samples) were selected for incurred sample reanalysis (ISR). The % difference between the re-assay concentrations and the original concentrations were all less than 15% of their mean values and met the acceptance criteria for ISR. [Copyright &y& Elsevier]

Abstract: Alumina nanoparticle-embedded-bismuth telluride matrix (Al2O3/Bi2Te3) composite powders were synthesized by chemical routes that employ a polyol reduction process to Bi acetates and Te chlorides in the solvent. With application of the polyol process, the synthesized composite powders show a disc-shaped morphology with 50nm thickness and 1μm diameter. High-resolution TEM images reveal that alumina nanoparticles are homogeneously embedded in the Bi2Te3 matrix powders. The Al2O3/Bi2Te3 nanocomposites sintered from the composite powders exhibit improved ZT values at room temperature compared to that of pure Bi2Te3 due to reduced thermal conductivity caused by active phonon and carrier scattering at the newly formed Al2O3/Bi2Te3 interface. [Copyright &y& Elsevier]

In molecular testing using PCR, the target DNA is amplified via PCR and the sequence of interest is investigated via hybridization with short oligonucleotide capture probes that are either in a solution or immobilized on solid supports such as beads or glass slides. In this report, we report the discovery of assembly of DNA complex(es) between a capture probe and multiple strands of the PCR product. The DNA complex most likely has branched structure. The assembly of branched DNA was facilitated by the product of asymmetric PCR. The amount of branched DNA assembled was increased five fold when the asymmetric PCR product was denatured and hybridized with a capture probe all in the same PCR reaction mixture. The major branched DNA species appeared to contain three reverse strands (the strand complementary to the capture probe) and two forward strands. The DNA was sensitive to S1 nuclease suggesting that it had single-stranded gaps. Branched DNA also appeared to be assembled with the capture probes immobilized on the surface of solid support when the product of asymmetric PCR was hybridized. Assembly of the branched DNA was also increased when hybridization was performed in complete PCR reaction mixture suggesting the requirement of DNA synthesis. Integration of asymmetric PCR, heat denaturation and hybridization in the same PCR reaction mixture with the capture probes immobilized on the surface of solid support achieved dramatic increase in the signal and sensitivity of detection of DNA. Such a system should be advantageously applied for development of automated process for detection of DNA. [ABSTRACT FROM AUTHOR]

Abstract: Extraction of TeO2 from the byproduct solution generated during the copper smelting process and application of the extracted TeO2 to the preparation of Bi–Te alloy thermoelectric materials were performed via a wet chemical processes. In the wet chemical process, powder purifying steps were optimized by adjusting the pH of NaOH solvent to dissolve the initially extracted Te compounds and by washing the finally extracted powders. TeO2 powders used in preparing the Bi–Te alloy thermoelectric materials could be successfully extracted from the byproduct solution by the optimized wet chemical process. Powders synthesized by applying the commercial and the extracted TeO2 powders to the wet chemical process showed identical crystal structures of Bi2Te3 and a mean particle size of ∼3μm. Thus, it is believed that the recycled TeO2 powders will be very useful in the preparation of Bi–Te alloy thermoelectric materials. [Copyright &y& Elsevier]

Abstract: Bismuth–antimony–tellurium-based nanopowders were fabricated by a chemical process in which dissolved Bi, Te and Sb salts were directly reduced in each element via surfactant-assistant polyol reducing agents. XRD patterns of the synthesized nanopowders showed that the formed phases correspond mainly to (Bi0.5Sb0.5)2Te3 and Bi0.5Sb1.5Te3, respectively. The phases revealed that the three different elements were stably alloyed as ternary composition in one powder via the simple chemical route. The nanopowders were consolidated into bismuth telluride-based bulk materials that exhibited electrical resistivity above 5.6×10−5 Ωm, 150μV/K of the Seebeck coefficient and 0.7W/mK of thermal conductivity at room temperature. These results showed that p-type thermoelectric nanopowders obtained from a simplified chemical process could be used in making thermoelectric materials towards high performances. [Copyright &y& Elsevier]

In this article, we present a subcarrier demodulation structure to eliminate an undesirable DC-offset phenomenon, which may appear in the baseband of the reader receiver under passive radio frequency identification environment.To achieve the requirement, the primary feature of the proposed demodulation structure is to reconstruct the signal corrupted by the DC-offset phenomenon by creating peak signals from the corrupted signal. In the case of the Miller subcarrier signal, the phase inversion information in the symbol duration is used for generating the peak signal. It is shown that the proposed method can successfully detect valid data from the received signal, even when the received baseband signal is distorted by the DC-offset phenomenon. In addition, the performance of the proposed method is slightly better than or comparable to that of the well-known-matched filter-type baseband receiver in the band-limited channel environments. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:1264-1272, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25995 [ABSTRACT FROM AUTHOR]

Abstract: A new compatibilizer, poly(vinyl benzyloxy methyl naphthalene)-g-poly(t-butyl methacrylate-co-methacrylic acid), was synthesized for Nylon 66 (N66)/multi-walled carbon nanotube (MWCNT) composites. It has been shown that the naphthalene unit in the main chain of the compatibilizer interacts with MWCNTs by π–π interaction and that the carboxylic acid unit in the graft chain of the compatibilizer interacts with the amide group of N66. The use of the compatibilizer produces well-dispersed MWCNTs in N66 matrix, which results in improved mechanical and electrical properties of the composites, while the simple mixture of N66/MWNCTs without the compatibilizer exhibits poor mechanical and electrical properties due to severe aggregation of MWCNTs. It is also found that the compatibilizer with a small amount of carboxylic acids is more effective for improving the mechanical and electrical properties of N66/MWCNT composites. [Copyright &y& Elsevier]

The microstructure of carbon nanotube reinforced copper matrix (CNT/Cu) nanocomposites, processed by molecular-level mixing, exhibits CNTs homogeneously dispersed in the Cu matrix. Measured thermal conductivity of the fabricated CNT/Cu nanocomposites decreased as the CNT volume fraction increased from 5% to 10%. A low coefficient of thermal expansion (CTE) was obtained from the 10vol.% CNT/Cu nanocomposite. These results indicate that embedded CNTs provide CNT/metal interfaces as thermal barriers but also stiffen the metal matrix composites. [Copyright &y& Elsevier]

Objective: To assess the improvement of seminal characteristics and pregnancy rates after microsurgical varicocelectomy in men with subclinical varicocele. Design: Retrospective study. Setting: University infertility clinic. Patient(s): One hundred forty-three patients with a subclinical left-sided varicocele. Intervention(s): Patients who agreed to microsurgical varicocelectomy (n = 25, surgery group), medical treatment with L-carnitine (n = 93 drug group), and those who did not agree to any treatment (n = 25, observation group) were enrolled. Main Outcome Measure(s): Semen characteristics were reevaluated twice 6 months after treatment. The natural pregnancy rates were estimated by telephone interview between 1 and 2 years after treatment. Result(s): In the surgery group, sperm counts improved significantly after microsurgical varicocelectomy. In the drug group, however, sperm parameters did not significantly improve after treatment. Natural pregnancy rates were 60.0% in the surgery group, 34.5% in the drug group, and 18.7% in the observation group. The natural pregnancy rate of the surgery group was higher than the other groups, and there were statistically significant differences among the three groups. Conclusion(s): Surgical treatment is the best option for management of subclinical varicocele. [Copyright &y& Elsevier]

Abstract: The cumbersome process required for diagnosis by DNA microarray can be simplified by simple extraction of nucleic acid from cells and by integration of liquid-phase polymerase chain reaction (PCR) and hybridization on the surface of a microarray slide. An unexpected benefit was the large (five- to sixfold) increase in detection signal that also is translated into an increase in sensitivity and the confidence level of diagnosis. The large increase in the detection signal appears to be due to participation of PCR primers as well as to extension of the immobilized capture probes during the hybridization process. The reason for the large increase in signal is not clear in view of only one round of DNA synthesis during the hybridization step. The integrated process correctly identified various genotypes of human papillomavirus (HPV) in the infected clinical human cervical specimens with specificity and efficiency. The process described in this article saves labor, time, and cost and should be applicable for automation of diagnosis by DNA microarray. [Copyright &y& Elsevier]

Abstract: A compatibilizer, poly(3-hexylthiophene)-graft-poly(t-butyl acrylate-co-acrylic acid) was synthesized, where the acrylic aid was formed by hydrolysis of t-butyl acrylate unit. It has been identified that poly(3-hexylthiophene) backbone of the compatibilizer interacts with multi-walled carbon nanotubes (MWCNTs) via π–π interaction and the acrylic acid unit of the graft chain interacts with Nylon 66 (N66) matrix via hydrogen bonding. When a small amount of compatibilizer was added to N66/MWCNT composites, MWCNTs were more homogeneously dispersed in N66 matrix than the case without compatibilizer. As a consequence, mechanical and electrical properties of the composites with compatibilizer were largely improved as compared with those of composites without compatibilizer. [Copyright &y& Elsevier]

• Performance of Bi 2 Te 3 -based thermoelectric modules was tailored by diffusion barriers comprising EN and ENEPIG. • Dissimilar coating led to different contact resistance for Bi 2 Te 3 -based thermoelectric modules. • ENEPIG coating yielded better performance of Bi 2 Te 3 -based thermoelectric modules as compared to EN coating. [Display omitted] Fifty-pair Bi 2 Te 3 -based thermoelectric (TE) modules were produced by spreading Sn alloy solder on Cu electrodes before heating at 270 °C for 10 min to connect Bi 2 Te 3 -based legs with Cu electrodes. To suppress unexpected reactions between solder and TE materials, a conventional electroless nickel (EN) layer and a novel coating encompassing EN, electroless palladium, and immersion gold (ENEPIG) layers were adopted for Bi 2 Te 3 materials as diffusion barriers. Influence of different diffusion barriers, namely, EN and ENEPIG, on TE performance of module was ascertained. Interfacial structure at Bi 2 Te 3 /solder/Cu electrode interface revealed that intermetallic compounds were generated owing to interdiffusion among Cu, Sn, and coating elements, and they mostly concentrated at Bi 2 Te 3 /solder and solder/Cu electrode interfaces. Additionally, ENEPIG coating exhibited much better wettability with solder than the EN coating, resulting in fewer defect sites at Bi 2 Te 3 /solder interface. When current flowed through TE modules, the ENEPIG-coated module yielded lower temperatures on both hot and cold sides than the EN-coated module. While the modules had temperature differences between two substrates, output power generated by the ENEPIG-coated module was higher than that of the EN-coated module. In addition, the ENEPIG-coated module showed a smaller internal resistance than the EN-coated module. After heating at 200 °C for 200 h, both modules presented markedly reduced output power, whereas internal resistance was escalated. [ABSTRACT FROM AUTHOR]

Abstract: In this work, we provide a direct proof concerning a special type of concave density function on a bounded closed interval with minimal variance. This proof involves elementary methods, without using any advanced theories such as Weierstrass’s Approximation Theorem, from which the technical core result of the paper [C. Carlsson, R. Fullér, P. Majlender, On possibilistic correlation, Fuzzy Sets and Systems 155 (2005) 425–445] comes. [Copyright &y& Elsevier]

Abstract: Carbon nanotube (CNT) reinforced Cu matrix (CNT/Cu) nanocomposites are fabricated by a novel fabrication process, named as molecular level process, which involves suspending CNTs in solvent by surface functionalization, mixing Cu ions with CNT suspension, drying, calcination and reduction. The molecular level process produces CNT/Cu nanocomposite powders, in which the CNTs are homogeneously implanted within Cu powders. The nanocomposite powders are consolidated into CNT/Cu nanocomposites by spark plasma sintering. The hardness and sliding wear resistance of CNT/Cu nanocomposite are enhanced by two and three times, respectively, compared to those of Cu matrix. The enhancement of hardness is due to the effect of homogeneous distribution of CNTs in Cu matrix, good bonding at CNT/Cu interfaces and high relative density of nanocomposites. The dispersed CNTs in Cu-matrix nanocomposite gives significantly enhanced wear resistance by retarding the peeling of Cu grains during sliding wear process. [Copyright &y& Elsevier]

Abstract: Carbon nanotubes (CNTs) have been considered as an ideal reinforcement to improve the mechanical performance of monolithic materials. However, the CNT/metal nanocomposites have shown lower strength than expected. In this study, the CNT reinforced Cu matrix nanocomposites were fabricated by spark plasma sintering (SPS) of high energy ball-milled nano-sized Cu powders with multi-wall CNTs, and followed by cold rolling process. The microstructure of CNT/Cu nanocomposites consists of two regions including CNT/Cu composite region, where most CNTs are distributed, and CNT free Cu matrix region. The stress–strain curves of CNT/Cu nanocomposites show a two-step yielding behavior, which is caused from the microstructural characteristics consisting of two regions and the load transfer between these regions. The CNT/Cu nanocomposites show a tensile strength of 281MPa, which is approximately 1.6 times higher than that of monolithic Cu. It is confirmed that the key issue to enhance the strength of CNT/metal nanocomposite is homogeneous distribution of CNTs. [Copyright &y& Elsevier]