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This paper proposes a location authentication method to prevent wormhole payment attack in Samsung Pay. The primary feature of this method is comparing wireless Access Point (AP) information collected by the current Samsung Pay user and a wireless AP model (WM) that was created from wireless AP information (WI) sent by previous Samsung Pay users. To create the WM, an autoencoder is used. Unlike the existing location authentication techniques that use WI, our method does not require additional hardware, modification of the Point of Sale (POS) software, or any pre-requisite information such as the location coordinates of the POS. We show that the proposed location authentication technique exhibits the minimum Equal Error Rate (EER) of 2.4% in real payment environments.

Dual-energy material decomposition (DEMD) is a well-established theoretical x-ray technique that uses low- and high-kilovoltage radiographs to separate soft tissue and bone in radiography and computed tomography (CT). However, it requires double exposures that result in increased patient radiation doses, causes increases in the execution time, and generates errors due to misregistration attributed to the patient motion between two scans. In this study, we investigated a low-dose, single-energy material decomposition (LSEMD) method in radiography using a sparse-view CT scan where the attenuation length in the object was estimated from the CT image. We performed a systematic simulation and an experiment to demonstrate the feasibility of use of the LSEMD method in radiography. Only 60 projections, far fewer than those required by the Nyquist sampling theory, were acquired at an x-ray tube voltage of 80 kVp, and were used to reconstruct a sparse-view CT image with a state-of-the-art dictionary-learning (DL) algorithm. We investigated the image performance of the LSEMD and compared the elicited results with those obtained with the use of DEMD (80 kVp and 120 kVp were used). Our results indicate that the DL algorithm produced high-quality sparse-view CT images. Accordingly, the LSEMD method yielded material decomposition results that were very similar to the results elicited by the conventional DEMD method in radiography. [ABSTRACT FROM AUTHOR]

The milling of highly flexible workpieces, such as thin-walled structures used in turbine blades, aerospace equipment, and jet engine compressors, requires vibration compensation to improve the quality of the workpiece surface. Vibration can be reduced by selecting appropriate cutting parameters. However, this approach reduces system productivity. This paper presents an active workpiece holder that controls the vibration of general computer numerical control machine tools. The proposed holder, which comprises a flexible guide mechanism, driver, and sensor, measures vibration and actively controls it using piezoactuators. A high-rigidity flexure mechanism was designed for the holder, and finite element method simulation and modal analysis were performed. Finally, the proposed system was fabricated, and experimental verification indicated that the system reduced vibration. The surface quality obtained using the controlled system was ∼50% better than that obtained using the uncontrolled system. [ABSTRACT FROM AUTHOR]

Objective: To evaluate Ontario's provincial varicella vaccination program through analysis of aggregate varicella cases in order to determine whether there has been a decrease in reportable disease burden; and to assess varicella vaccine adverse events following immunization (AEFIs).Methods: Aggregate varicella cases (1993-2013) were extracted from the reportable disease databases. Pre-program (1993-2004) and post-program (2007-2013) periods were chosen according to implementation of the publicly funded vaccination program. AEFIs following administration of varicella vaccines (2010-2013) were also extracted. Reporting rates were calculated using net doses distributed as the denominator. Serious AEFIs were defined using World Health Organization standards.Results: The incidence of aggregate varicella reports decreased significantly over the study period (from 311.4 to 22.2 cases per 100,000 population in 1993 and 2013, respectively). Incidence also decreased significantly in all age groups between the pre- and the post-program periods with a shift in age distribution towards older individuals in the post-program period. A total of 162 AEFIs following varicella vaccine were reported between 2010 and 2013 for an annualized reporting rate of 14.6 per 100,000 doses distributed. The most common events were rash (37.3%), including eight reports of varicella-like rash (0.7 per 100,000 doses distributed). Ten serious events were reported (0.9 per 100,000 doses distributed), and all vaccine recipients recovered.Conclusion: Significant reductions in varicella disease incidence and low AEFI reporting rates were observed with the introduction of the publicly funded varicella vaccine program in Ontario. Continued surveillance is indicated to further assess trends in varicella disease and vaccine safety. [ABSTRACT FROM AUTHOR]

The strain-induced cracks in organic microtubules composed of an organic charge transfer (CT) complex of 1,2,4,5-tetracyanobenzene (TCNB) and naphthalene were selectively welded via the formation of secondary CT complexes; this process, in turn, led to the formation of organic hetero-microtubules consisting of multiple segments of two organic CT complexes. [ABSTRACT FROM AUTHOR]

In this paper, we will discuss piezoelectric energy harvesters of multi-layered ceramic-pillar composite structures to be used as the energy source of small size electronic devices. 0.2(PbMg1/3Nb2/3O3)-0.8(PbZr0.475Ti0.525O3) ceramics and polydi-methylsiloxane (PDMS) were employed as piezoelectric ceramic-pillar composite, which prepared in forms of rectangular pillar structures. The piezoelectric ceramic-pillar composites were sintered separately and attached on the metallic bottom electrode with poled states. Symmetric upper electrodes were attached on the other side. Subsequently, the ceramic-pillar structures of composite material were manufactured with single-layer, double-layer and triple-layer devices. Both of multi-layer and single layer devices will be compared with several analysis methods. Piezoelectric properties will be discussed including the piezoelectric constant. Also, the output power of the multi-layer and single layer devices will be studied. [ABSTRACT FROM AUTHOR]

With the increasing demand of auxiliary power unit in portable electronic devices, the concept of renewable energy harvesting near human surrounding environmental circumstance arouses an interest. As the field of microelectromechanical system (MEMS) has advanced, a clear need for the integration of materials other than silicon and its compounds into micromachined transducers has emerged. Piezoelectric materials are high energy density materials that scale very favorably upon miniaturization and that has led to an ever-growing interest in piezoelectric films for MEMS applications. However, conventional powder processing and machining cannot meet the requirement of such fine ceramic structure. Advanced technologies such as those using lasers and soft PDMS modeling method have been available for micro-patterning of ceramics but are not viable for large-scale production. It is difficult and time-consuming to pattern fine scale ceramics. In this paper, we fabricated simple process of MEMS based energy harvester by employing the flammable materials with PMN-PZT micro-pillar structure. The optimum aspect ratio of thickness/length for the ceramic pillar dielectric properties and micro-structure will be discussed. [ABSTRACT FROM AUTHOR]

In this study, the high-quality factor (Q) metamaterial interdigital transmission line (TL) based on the complementary spiral resonators (CSRs) is presented for reducing the phase noise of the voltage-controlled oscillator (VCO). The high-Q metamaterial TL is realised by adopting the array of the CSRs etched on the ground plane and the interdigital centre line on the signal plane. The interdigital centre line on the signal plane has been used to obtain higher Q value than that of the conventional implementation. The resonance properties and inherent Q value saturation of the proposed high-Q metamaterial interdigital TL have been analysed as follows: width of the centre line on the signal plane, dimensions of the CSRs, current directions between the CSRs, number of the unit cell-pair of the CSRs and whether or not there is the interdigital structure. The phase noise and tuning range of the proposed VCO are -127.50 to -124.87 dBc/Hz at 100 kHz and 5.744-5.86 GHz. [ABSTRACT FROM AUTHOR]

In this paper, a high-efficiency wireless energy transmission via magnetic resonance is experimentally implemented in a resonator with the various sizes of transmitting and receiving coils and the receiving coil having two shapes of rectangular and circular types. The transmission efficiency is analyzed by varying the transmission distance. The resonance between the transmitting and receiving coils is achieved with lumped capacitors terminating the coils. The transmission efficiency of the resonator consisting of a circular transmitting coil with a diameter of 60 cm and rectangular receiving coil with a one side length of 10 cm is about 80% at the transmission distance of 20 cm. The transmission efficiencies of the wireless energy transmission resonator consisting of a receiving coil with the size of iPhone4 are about 75% and 40% at the transmission distances of 20 cm and 50 cm. [ABSTRACT FROM AUTHOR]

A plasma generator for a long pulse H+/D+ ion source has been developed. The plasma generator was designed to produce 65 A H+/D+ beams at an energy of 120 keV from an ion extraction area of 12 cm in width and 45 cm in length. Configuration of the plasma generator is a multi-cusp bucket type with SmCo permanent magnets. Dimension of a plasma chamber is 25 cm in width, 59 cm in length, and 32.5 cm in depth. The plasma generator was designed and fabricated at Japan Atomic Energy Agency. Source plasma generation and beam extraction tests for hydrogen coupling with an accelerator of the KSTAR ion source have been performed at the KSTAR neutral beam test stand under the agreement of Japan-Korea collaborative experiment. Spatial uniformity of the source plasma at the extraction region was measured using Langmuir probes and ±7% of the deviation from an averaged ion saturation current density was obtained. A long pulse test of the plasma generation up to 200 s with an arc discharge power of 70 kW has been successfully demonstrated. The arc discharge power satisfies the requirement of the beam production for the KSTAR NBI. A 70 keV, 41 A, 5 s hydrogen ion beam has been extracted with a high arc efficiency of 0.9 -1.1 A/kW at a beam extraction experiment. A deuteron yield of 77% was measured even at a low beam current density of 73 mA/cm2. [ABSTRACT FROM AUTHOR]

Study design:Case-control study.Objectives:To investigate changes of biomechanical skin properties and their relationship with paralysis following spinal cord injury (SCI).Setting:South Korea.Methods:A total of 48 male subjects with chronic SCI and 48 age-matched healthy controls were enrolled into this study. The C4 shoulder group and L2 thigh group were prescribed by two measured anatomical regions that represented the C4 and L2 American Spinal Injury Association sensory dermatomes. Each anatomical group was comprised of one control subgroup and three SCI subgroups determined by sympathetic paralysis at the measured region and somatic completeness. The following biomechanical skin properties were compared between the subgroups in each anatomical group by using Cutometer, a non-invasive suction device: distensibility (Uf), elasticity (Ua/Uf and Ur/Uf) and viscoelasticity (Uv/Ue and H). The impact of sympathetic and somatic sensory paralysis, somatic completeness, age, smoking, body mass index and duration of injury on the indices of skin properties were analyzed.Results:In each anatomical group, sympathetic paralyzed subgroups regardless of somatic sensory completeness showed lower value of skin distensibility (Uf), and higher values of elasticity (Ua/Uf and Ur/Uf) and viscoelasticity (Uv/Ue and H), compared with other subgroups. Age and duration of injury had significant impact on biomechanical skin properties.Conclusion:The non-invasive suction method is useful for quantitative evaluation of skin affected by SCI. In chronic SCI patients, biomechanical skin properties are significantly altered in the skin with sympathetic paralysis rather than somatic sensory paralysis. [ABSTRACT FROM AUTHOR]

A 1.8-GHz power amplifier is implemented using the 0.18-µm Radio Frequency (RF) Complementary Metal Oxide Semiconductor (CMOS) process. An additional thin-film technology on a separate substrate is used to design the output matching network for high efficiency. To minimise the number of bond-wires, a single differential power stage is used. The output matching network was completed with the proposed load impedance transformer and an Metal Insulator Metal (MIM) capacitor using additional thin-film technology. The amplifier achieved a drain efficiency of 50.5% at a maximum output power of 31.6 dBm at 1.81 GHz. [ABSTRACT FROM AUTHOR]

AIM OF THE STUDY: Traditionally, the stem and root bark of Ulmus davidiana var. japonica (Ulmaceae) are Korean herbal medicines used for anti-inflammatory and anticancer therapy. In this study, we investigated the protective effects of Ulmus davidiana var. japonica ethanolic extract (UD) in a murine asthma model. Furthermore, we determined whether heme oxygenase (HO)-1 is required for the protective activity of UD. MATERIALS AND METHODS: Airways of ovalbumin (OVA)-sensitized mice exposed to OVA challenge developed eosinophilia, mucus hypersecretion and increased cytokine levels. UD was applied 1h prior to OVA challenge. Mice were administered UD orally at doses of 100 and 200mg/kg once daily on days 18-23. Bronchoalveolar lavage fluid (BALF) was collected 48 h after the final OVA challenge. Levels of interleukin (IL)-4 and IL-5 in BALF were measured using enzyme-linked immunosorbent assays (ELISAs). Lung tissue sections 4 microm in thickness were stained with Mayer's hematoxylin and eosin for assessment of cell infiltration and mucus production with PAS (periodic acid shift reagent) staining, in conjunction with ELISA, immunohistochemistry and Western blot analyses for HO-1 protein expression. RESULTS AND CONCLUSION: Orally administered UD significantly inhibited the number of OVA-induced inflammatory cells and IgE production, along with reduced T-helper (Th)2 cytokine levels, such as IL-4 and IL-5, in BALF and lung tissue. In addition, UD induced a marked decrease in OVA-induced reactive oxygen species (ROS), inflammatory cell infiltration and mucus production in lung tissue. These effects were correlated with HO-1 mRNA and protein induction. Our results indicate that UD protects against OVA-induced airway inflammation, at least in part, via HO-1 upregulation. [ABSTRACT FROM AUTHOR]

Background: A web-based survey was conducted among colorectal surgeons who represented members of both SAGES and ASCRS to find out how they define conversion for laparoscopic colorectal surgery.Methods: Questionnaires were designed based on MCQs, including three parts: surgeon information, different definitions for conversion, and four different clinical scenarios. Surgeons were asked to choose the best definition(s).Results: 325 (28.5%) of 1,140 surgeons, 28.5% responded; approximately half of them were part of private-based practices. Fifty-three percent had more than 10 years experience; 35.9% performed more than 50 laparoscopic colon cases per year, 12% performed more than 25 laparoscopic rectal cases per year, and 60% less than 10. The majority (68.4%) agreed that any incision made earlier than planned is conversion. Whereas 81.4% felt that incision >5 cm is not a conversion, only 53.4% considered incision >10 cm a conversion, and 37% did not. Neither extracorporeal vessel ligation (73.8%), bowel resection (81.2%), anastomosis (77%), or incision made for specimen retrieval (91.1%) was counted as conversion. In clinical case scenarios, 62% found an incision made to facilitate phlegmon dissection after laparoscopically mobilizing the left colon up to and around the splenic flexure to be laparoscopic-assisted. A 10-cm incision required for fistula take down after finishing laparoscopic dissection was defined as conversion (55.6%). A 10-cm incision made for the rectal dissection in rectopexy was described as conversion in 51% and laparoscopic-assisted in 48%. Increasing a 5-12-cm for specimen extraction, 49.3% was declared a laparoscopic-assisted case.Conclusions: It was considered clear that any incision made earlier than planned a conversion, whereas extra corporeal vessel ligation, bowel resection and anastomosis were not. However, there seem to be many views of conversion regarding incision length, and some clinical situations that might influence outcome among different centers. [ABSTRACT FROM AUTHOR]

BACKGROUND: Proximal chevron osteotomy (PCO) for hallux valgus is inherently more stable than the other forms of proximal metatarsal osteotomy, but complications, such as, delayed union, nonunion, and malunion can occur. In this study, we have compared results of two axial Kirschner wire fixation with or without transverse Kirschner wires in PCO for moderate to severe hallux valgus deformities. METHODS: A prospective study was conducted on 65 patients (85 feet) that underwent PCO and a distal soft tissue procedure for moderate to severe hallux valgus. Patients were divided into two groups, two axial Kirschner wire fixation (Group I) and two axial and supplementary transverse Kirschner wire fixation (Group II). Group I comprised 41 feet of 32 patients and Group II 44 feet of 33 patients. RESULTS: Average AOFAS scores were 52.8 points in group I and 49.6 points in group II preoperatively, and 92.8 and 89.6 points, respectively, at last followup. Patients were very satisfied or satisfied in 92.7% in Group I and 93.2% in Group II. Average hallux valgus angles in Groups I and II changed from 34.9 degrees and 37.2 degrees preoperatively to 12.3 degrees and 13.9 degrees postoperatively, and intermetatarsal angles in Groups I and II changed from an average of 17.9 degrees and 17.2 degrees preoperatively to 10.3 degrees and 10.4 degrees postoperatively. No significant inter-group differences were found. CONCLUSION: Supplementary transverse Kirschner wire fixation is not recommended for proximal metatarsal chevron osteotomy since two axial Kirschner wires provided sufficient stability. [ABSTRACT FROM AUTHOR]

This paper presents the dynamic infinite element formulations that have been developed for soil-structure interaction analysis both in frequency domain and time domain by the present authors and our colleagues during the past 20 years. Axisymmetric, 2D and 3D layered half-space soil media were considered in the developments. The displacement shape functions of the infinite elements were established using approximate expressions of analytical solutions in frequency domain to represent the characteristics of multiple waves propagating into the unbounded outer domain of the media. The shape functions were determined in terms of the excitation frequency as well as the spatial and material characteristics of the far-field soil region. Thereby the element mass and stiffness matrices are frequency dependent. As for time domain analysis, the shape functions were further simplified to obtain closed-form frequency-dependent mass and stiffness matrices, which can analytically be transformed into time domain terms by the Fourier transform. The proposed infinite elements were verified using benchmark examples, which showed that the present formulations are very effective for the soil-structure interaction analysis either in frequency or in time domain. Example applications to actual soil-structure interaction problems are also given to demonstrate the capability and versatility of the present methodology. [ABSTRACT FROM AUTHOR]