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Three-dimensional (3D) nanoarchitectures have offered unprecedented material performances in diverse applications like energy storages, catalysts, electronic, mechanical, and photonic devices. These outstanding performances are attributed to unusual material properties at the nanoscale, enormous surface areas, a geometrical uniqueness, and comparable feature sizes with optical wavelengths. For the practical use of the unusual nanoscale properties, there have been developments for macroscale fabrications of the 3D nanoarchitectures with process areas over centimeter scales. Among the many fabrication methods for 3D structures at the nanoscale, proximity-field nanopatterning (PnP) is one of the promising techniques that generates 3D optical holographic images and transforms them into material structures through a lithographic process. Using conformal and transparent phase masks as a key factor, the PnP process has advantages in terms of stability, uniformity, and reproducibility for 3D nanostructures with periods from 300 nm to several micrometers. Other merits of realizing precise 3D features with sub-100 nm and rapid processes are attributed to the interference of coherent light diffracted by phase masks. In this review, to report the overall progress of PnP from 2003, we present a comprehensive understanding of PnP, including its brief history, the fundamental principles, symmetry control of 3D nanoarchitectures, material issues for the phase masks, and the process area expansion to the wafer-scale for the target applications. Finally, technical challenges and prospects are discussed for further development and practical applications of the PnP technique.

Hemoglobin level determines blood viscosity and as hemoglobin level rises, blood pressure rises. However, hemoglobin level in individuals is not fixed and change in hemoglobin is affected by various clinical conditions. The purpose of this study is to investigate whether the hemoglobin variability affects the development of hypertension using Korean cohort database. This study was conducted with 94,798 adults (age ≥ 40 years) who visited the health screening in 2006 or 2007 (index year) and had at least 3 health screenings from 2002 to 2007. Hemoglobin variability was assessed by 3 indices of coefficient of variation (CV), standard deviation, and variability independent of the mean. Cox proportional hazard regression analysis was performed for each index of quartile groups (Q1–Q4). A total of 29,145 participants (30.7%) had the incidence of hypertension during a median follow-up of 7.4 ± 2.5 years. In the multivariable adjusted model, the hazard ratio and 95% confidence interval for incidence of hypertension of Q2, Q3, and Q4 compared with Q1 of hemoglobin variability CV were 1.014 [0.981–1.047], 1.064 [1.030–1.099] and 1.094 [1.059–1.131] respectively. The results were consistent in various sensitivity and subgroup analyses. This study showed that hemoglobin variability could be associated with hypertension development.

In this paper, we first propose power distribution network (PDN) model of the perforated power and ground (P/G) planes including substrate effects and multiarray through-silicon vias (TSVs) for a silicon interposer. Since it is almost impossible to simulate a high metal density perforated PDN structure, we first suggest a modeling methodology for P/G perforated planes to reduce simulation time significantly with a high accuracy. To obtain the PDN impedance of a silicon interposer faster, we convert the perforated planes to solid planes with a dielectric mixture. The capacitance (C) and conductance (G) component of perforated P/G planes are precisely estimated based on the conformal mapping method. From the estimated C and G, the physical dimension and material properties of the dielectric mixture of solid P/G planes are determined, respectively. Because silicon interposer PDN consists of a periodic structure, we design and analyze the unit cell of a PDN thoroughly. From the unit cell analysis, the electrical characteristic of an entire PDN for a silicon interposer is successfully estimated. The PDN impedance of the proposed solid and perforated P/G planes and simulation time to obtain each PDN impedance are compared and evaluated, respectively. The proposed methodology is validated by a full 3-D electromagnetic (EM) simulation in the frequency range from 0.01 to 20 GHz. We also proposed models of multiarray P/G TSVs that can be applied to the various P/G patterns for a silicon interposer. From the inductance matrix considering current directions, the self- and mutual inductances of TSVs are accurately calculated. Because quasi-transverse electromagnetic mode is propagated through TSVs and the substrate dielectric of a silicon interposer can be regarded as a uniform dielectric, the capacitance and conductance of TSVs can be calculated from the inductance matrix. The proposed model of multiarray TSVs is also analyzed and verified by EM simulations in the frequency range from 0.01 to 20 GHz with a high accuracy.

This paper, for the first time, proposed a novel eye-diagram estimation method for pulse amplitude modulation with N -level (PAM-N) signaling. For verification, a through-silicon via (TSV) channel was fabricated. Because the input of the proposed method is an insertion loss, the loss of the fabricated TSV channel was measured up to 110 GHz. The estimated eye diagrams and measured eye diagrams were compared for the same TSV channel. The proposed method and measurements have nearly the same eye-height and eye-width values at data rates of 2, 4, and 8 Gb/s. Therefore, the proposed method successfully provides PAM-N's eye diagram with the insertion loss. Furthermore, bathtub curves were compared for the proposed method and measurements. The proposed method provides a bathtub curve up to 10–12, but in contrast, the measurements only provide a bathtub curve up to 10–5 due to a limited number of samples. Both of the bathtub curves are nearly the same up to 10–5 in amplitude. In conclusion, the eye-diagram estimation method for PAM-N signaling is successfully proposed and verified.

Herein, a photo-crosslinkable coumarin-containing polymer, poly(7-(4-vinyl-benzyloxyl)-4-methylcoumarin) or PVBMC, was prepared, and its physicochemical and electrical properties as a gate dielectric in organic electronic devices, such as organic thin-film transistor (OTFT) and inverter, was evaluated. The crosslinking of PVBMC by exposure to UV light (365 nm) over time was characterized using Fourier-transform IR and UV–visible spectroscopy. The measured capacitance of the cross-linked PVBMC thin film in a metal-insulator-metal-type capacitor was as high as 36.4 pF/mm2. Pentacene-based OTFT and load-type inverter with the cross-linked PVBMC gate dielectric were prepared, and their electrical responses were evaluated under ambient conditions. The OTFT showed dominant hole charge carrier transport behavior with a field-effect mobility of 1.52 × 10−1 cm2/Vs and negligible hysteresis. The load-type inverter based on the OTFT exhibited moderate static and dynamic switching responses to the applied electrical pulse. These results suggest the potential application of photo-crosslinked PVBMC as a gate dielectric in the fabrication of high-performance OTFT-based devices.

Despite the advantages of video-based learning content, the video involves learners as passive viewers instead of active participants. We first conducted formative interviews with 12 participants to investigate natural user behaviors when learners have questions while watching online video lectures, and the result reveals that learners usually use web search to find answers for questions. Based on the formative interview results, we designed and developed HyperButton, an interactive video interface that supports collaborative question answering via in-video buttons and hyperlinks. In the user study, we find that HyperButton significantly improves the usability of the video interface. We further discuss design implications for an interactive video interface augmented with learner-generated material at scale.

The realization of high‐contrast modulation in optically transparent media is of great significance for emerging mechano‐responsive smart windows. However, no study has provided fundamental strategies for maximizing light scattering during mechanical deformations. Here, a new type of 3D nanocomposite film consisting of an ultrathin (≈60 nm) Al2O3 nanoshell inserted between the elastomers in a periodic 3D nanonetwork is proposed. Regardless of the stretching direction, numerous light‐scattering nanogaps (corresponding to the porosity of up to ≈37.4 vol%) form at the interfaces of Al2O3 and the elastomers under stretching. This results in the gradual modulation of transmission from ≈90% to 16% at visible wavelengths and does not degrade with repeated stretching/releasing over more than 10 000 cycles. The underlying physics is precisely predicted by finite element analysis of the unit cells. As a proof of concept, a mobile‐app‐enabled smart window device for Internet of Things applications is realized using the proposed 3D nanocomposite with successful expansion to the 3 × 3 in. scale., Mechano‐responsive smart windows are developed using stretchable 3D hybrid nanocomposites. The inserted periodic oxide nanoshell in the elastomer offers formation of light scattering air gaps upon stretching, and this provides high‐contrast optical modulation. It is demonstrated that smart window devices can be prepared for self‐responding to the surrounding environments and temporary projection screens by integrating with Internet of Things technology.

The classification of high-dimensional data is a very important problem that has been studied for a long time. Many studies have proposed linear classifiers based on Fisher’s linear discriminant rule (LDA) which consists of estimating the unknown covariance matrix and the mean vector of each group. In particular, if the data dimension p is larger than the number of observations n ( p > n ) , the sample covariance matrix cannot be a good estimator of the covariance matrix due to the well-known rank deficiency. To solve this problem, many studies proposed methods by modifying the LDA classifier through diagonalization or regularization of covariance matrix. In this paper, we categorize existing methods into three cases and discuss the shortcomings of each method. To compensate for these shortcomings, our baseline idea is that we consider estimation of the high dimensional mean vector and covariance matrix altogether while existing methods focus on shrinkage estimator of either mean vector or covariance matrix. We provide theoretical result that the proposed method is successful in both sparse and dense situations of the mean vector structures. In contrast, some existing methods work well only under specific situations. We also present numerical studies that our methods outperform existing methods through various simulation studies and real data examples such as electroencephalogy (EEG), gene expression microarray, and Spectro datasets.

In this paper, for the first time, we designed and analyzed channels between a graphic processing unit and memory in a silicon interposer for a 3-D stacked high bandwidth memory (HBM). We thoroughly analyzed and verified the electrical characteristics of the silicon interposer considering various design parameters, such as the channel width and space, redistribution layer via, and under bump metallurgy pads. In particular, we also considered the meshed ground planes used for the proposed transmission lines, which are microstrip and strip lines. Signal integrity (SI) of the proposed channels in the silicon interposer was successfully analyzed and verified using a full 3-D electromagnetic solver and circuit simulations. Based on the extracted lumped circuit resistance, inductance, conductance and capacitance parameters, we thoroughly analyzed the channel characteristics and identified the parameters that dominantly affect SI in relation to each frequency range. From the analyzed insertion loss and far end crosstalk, we verified SI of the silicon interposer by eye-diagram simulations in terms of eye-height voltage and timing jitter in the time domain. In the worst case, the eye-height voltage and timing jitter of the proposed microstrip lines are 0.911 V and 36.8 ps, respectively, with 72 mV of signal coupling. The eye-height voltage and timing jitter of the proposed strip line are 0.887 V and 42.1 ps with 34 mV of single couplings. We show that the proposed channels of the silicon interposer can successfully transfer data at a 2-Gb/s data rate. Finally, we propose concepts and solutions for the next-generation HBM interface with higher data rates up to 8 Gb/s.

Current wireless power transfer (WPT) systems have limited charging distance and high induced electromagnetic field (EMF) leakage. Thus, we first proposed a thin printed circuit board (PCB) type hybrid metamaterial slab (HMS) combining two kinds of metamaterial cell structures. The metamaterial cells in the center area of the HMS have zero relative permeability and straighten the magnetic field direction. The metamaterial cells located at the edges of the HMS have negative relative permeability and change the outgoing magnetic fields to opposite direction by magnetic boundary condition. Therefore, the magnetic field can be more confined between transmitter and receiver coils, enhancing the power transfer efficiency, while decreasing the EMF leakage in a WPT system. In this paper, we demonstrated that increased power transfer efficiency from 34.5% to 41.7% and reduced EMF leakage from −19.21 to −26.03 dBm in 6.78-MHz WPT system. Furthermore, we proposed new analysis method for relative permeability measurement of the metamaterial using a novel cubic structure with perfect electrical conductor and perfect magnetic conductor boundary.

Not all loads contribute to fatigue crack propagation in the welded detail of steel bridges when they are subjected to variable amplitude loading. For fatigue assessment, therefore, non-contributing stress cycles should be truncated. However, stress range truncation is not considered during typical fatigue reliability assessment. When applying the first order reliability method, stress range truncation occurs mismatch between the expected number of cycles to failure and the number of cycles obtained at the time of evaluation, because the expected number of cycles only counts the stress cycles that contribute to fatigue crack growth. Herein, we introduce a calibration factor to coordinate the expected number of cycles to failure to the equivalent value which includes both contributing and non-contributing stress cycles. The effectiveness of stress range truncation and the proposed calibration factor was validated via case studies.

High-quality rubrene crystals were directly grown on a polymeric gate dielectric-coated ITO/glass substrate by a simple solution process. Organic field-effect transistors were fabricated based on these rubrene crystals, and their electrical performance was investigated. Atomic force micrographs of the rubrene crystal reveal that its surface has a conventional terrace structure, confirming the well-ordered rubrene molecules. The organic transistor with the rubrene crystal shows the highest charge carrier hole mobility of 3.74 cm2/V·s that can be attributed to the strong π-π overlap between the adjacent rubrene molecules. The device shows a stable static and dynamic electrical stress response under ambient conditions. For evaluating the applicability of the transistor in a logic circuit, a simple load-type inverter is fabricated by combining the rubrene transistor and a 10 MΩ load-resistor, to achieve a clear dynamic switching response up to 100 Hz.

ZnO is a potential thermoelectric material because of its non-toxicity, high thermal stability, and relatively high Seebeck coefficient (S) of metal oxides. However, the extremely low figure of merit (zT), which comes from a high thermal conductivity (κ) over 40 W m-1 K-1, limits the thermoelectric application of ZnO. In particular, below 500 K, ZnO exhibits a nearly negligible zT (

In this paper, we propose glass-interposer (GI) electromagnetic bandgap (EBG) structure with defected ground plane (DGP) for efficient and broadband suppression of power/ground noise coupling. We designed, fabricated, measured, and analyzed a GI-EBG structure with DGP for the first time. The proposed GI-EBG structure with DGP is thoroughly analyzed using the dispersion characteristics and estimated stopband edges, $f_{L}$ and $f_{U}$ . We experimentally verified that the proposed GI-EBG structure with DGP achieved power/ground noise isolation bandgap (below −30 dB) between $f_{L}$ of 5.7 GHz and $f_{U}$ of 11 GHz. Estimation of $f_{L}$ and $f_{U}$ using dispersion analysis, full 3-D electromagnetic (EM) simulation results, and measurement results achieved good correlation. Effectiveness of the proposed GI-EBG structure with DGP on suppression of the power/ground noise coupling to high-speed through glass via (TGV) channel is verified with 3-D EM simulation. As a result, the proposed EBG structure successfully and efficiently suppressed the power/ground noise coupling and improved the eye diagram of the TGV channel. Lastly, we embedded thin alumina film in the proposed EBG structure and achieved even broader power/ground noise suppression between 2.1 and 14.7 GHz.

As a demand for electrical systems with a wide data bandwidth has increased, high-performance packages ensuring high data rates, such as low power double data rate series, have become common. The need for high-performance test sockets has also emerged to test these packages. However, a conventional pogo pin socket has a limited test bandwidth due to the parasitic components arising from its spring. On the other hand, a silicone rubber socket satisfies the wide bandwidth requirement because it has low parasitic components due to high-density conductive metal powders in an elastic silicone rubber. In this paper, we propose an RLGC equivalent circuit model of a silicone rubber socket and first experimentally verify it. The proposed model is experimentally verified in the frequency domain by comparing the insertion loss obtained from the proposed model to the measurement up to 20 GHz. The proposed model is experimentally verified in the time domain by comparing the eye diagrams obtained from the proposed model to the measurement at a data rate of 12.5 Gb/s. Also, the insertion loss of the sockets with varied height, diameter, and pitch is analyzed using the proposed model. The proposed model provides physical insight of a silicone rubber socket, and it allows to determine whether a socket is reliable for testing high performance packages in a short time. It also gives us the idea how to design a high-performance test socket. Furthermore, we discuss the current capacity and life cycle of the silicone rubber socket in terms of signal integrity as well.

353 Background: Stereotactic body radiation therapy (SBRT) is an emerging treatment option for unresectable pancreatic cancer, and may be more effective and less toxic than intensity modulated radiation therapy (IMRT). Methods: We retrospectively reviewed unresectable stage I-III pancreatic adenocarcinoma treated with SBRT (5 fractions, 30-33Gy) or IMRT (25-28 fractions, 45-56Gy with concurrent chemotherapy) between 2008-2016 at our institution. The groups were compared with respect to overall survival (OS), local failure (LF), distant failure (DF), any failure (AF), proportion of patients becoming resectable, and incidence of acute toxicity. Competing risks methods were used for univariate (UVA) and multivariate analysis (MVA) for LF, DF and AF. All endpoints were calculated from end of RT. Results: Median follow-up for surviving patients was 12.9 months. 44 patients received SBRT and 226 patients received IMRT. Patients who received SBRT were older (45% vs 29% > 70 years old, p = 0.05). Otherwise there was no significant difference in baseline characteristics, including stage and duration of induction chemotherapy. On MVA, there was no significant difference in OS, LF, DF, or AF between IMRT and SBRT (p = 0.73, 0.81, 0.44, and 0.39 respectively). Median OS was 15.7 months, and the 1-year rate of LF was 34.4% for SBRT and 30.2% for IMRT. Response to induction chemotherapy was associated with longer OS (p = 0.03). There was no significant difference in the proportion of patients who were subsequently resected between IMRT (17%) and SBRT (7%; p = 0.11). Significantly more IMRT patients experienced acute G2+ GI toxicity (24% vs. 7%, p = 0.008), G2+ fatigue (42% vs. 7%, p < 0.0001), and G3+ hematologic toxicity (26% vs. 5%, p = 0.001) compared to SBRT. Conclusions: SBRT achieves similar disease control outcomes as IMRT, and is associated with less acute toxicity. This data suggests SBRT is an attractive technique for pancreatic radiotherapy because of improved convenience and tolerability with equivalent efficacy. However, the lack of observed advantages in disease control with this moderate-dose SBRT regimen suggests a role for increasing SBRT dose, if this can be accomplished without significant increase in toxicity.

With the advent of the Internet-of-Things paradigm, the amount of data production has grown exponentially and the user demand for responsive consumption of data has increased significantly. Herein, we present DART, a fast and lightweight stream processing framework for the IoT environment. Because the DART framework targets a geospatially distributed environment of heterogeneous devices, the framework provides (1) an end-user tool for device registration and application authoring, (2) automatic worker node monitoring and task allocations, and (3) runtime management of user applications with fault tolerance. To maximize performance, the DART framework adopts an actor model in which applications are segmented into microtasks and assigned to an actor following a single responsibility. To prove the feasibility of the proposed framework, we implemented the DART system. We also conducted experiments to show that the system can significantly reduce computing burdens and alleviate network load by utilizing the idle resources of intermediate edge devices.

In this paper we present a hybrid brain-computer interface (BCI) system that manipulates simultaneous localization and mapping (SLAM) for convenient control of a robot. Due to the low accuracy of classifying multi-class neural signals, using brain signals alone has been considered inadequate for precise control of a robotic systems. To overcome the negative aspects of BCI systems, we introduce a hybrid system where the BCI control of a robot is aided by SLAM. Subjects used electroencephalography (EEG) and electrooculography (EOG) to remotely control a turtle robot that is running SLAM in a maze environment. With the supplementary information on the surroundings provided by SLAM, the robot could calculate potential paths and rotate at precise angles while subjects give only high-level commands. Subjects could successfully navigate the robot to the destination showing the potential of utilizing SLAM along with BCIs.

Computational fluid dynamic (CFD) simulations were performed to assess the potential chlorine leak scenario in the super-urban area of South Korea, where the human population density is very high and numerous buildings exist near operational water treatment facilities. Flame acceleration simulator (FLACS) was used to predict the consequence from accidental chlorine releases out of one of the water treatment facilities for the nearby area having a size of 5 km × 3 km approximately. The ability to precisely implement 3-D geometries is crucial for a successful 3-D simulation. Thus, a method was proposed to rapidly and accurately implement geometry by importing computer aided-design (CAD) files provided by a government agency, and processing them using Auto CAD and MicroStation software programs. An accidental release from an 18-ton tank was simulated with three different wind directions to determine the expected evacuation distances. Results from the study showed that the endpoint distances varied depending on the density and arrangement of the buildings. Moreover, we employed physical barriers with varying heights for mitigating the effects of toxic gas releases and simulated how effectively they decreased the concentration of released chlorine.

The selective reduction of thermal conductivity while preserving the Seebeck coefficient and electrical conductivity is regarded as a key strategy for achieving the high dimensionless figure-of-merit (ZT) of thermoelectric materials. Here, we newly propose a periodic three-dimensional (3D) nanostructure that has an ability to significantly reduce thermal conductivity, resulting in an improved ZT value of thermoelectric materials near room temperature. A 3D nanostructured thermoelectric monolith is developed by electrochemical deposition of a Bi–Sb–Te ternary alloy into a highly ordered, interstitial porous network in an epoxy template predefined by advanced lithography. The resultant inch-scale, bicontinuous nanocomposite monolith released from a substrate can be easily transferred to a customized reliable platform for evaluating thermoelectric properties. The measured thermal conductivity is only ∼0.89 W mK−1 at 350 K due to greatly increased phonon boundary scattering without any degradation in the Seebeck coefficient and electrical conductivity, leading to an enhanced ZT value (∼0.56) which is ∼50% higher than that of an ordinary film with the same elemental composition. The 3D nanostructure developed here will provide new design opportunities for nanostructured thermoelectric materials, potentially usable in flexible thermoelectric coolers and wearable energy harvesting systems.

Patent ductus arteriosus (PDA) is the most common congenital cardiovascular disorder in dogs and requires an accurate diagnosis for an appropriate treatment. Cardiac MRI (cMRI) has been reported as a method for characterization of canine thoracic vasculature. However, to the authors' knowledge, no published studies describe evaluation of canine PDA through cMRI. Three dogs were selected for this exploratory study. Electrocardiogram gating and breath-hold techniques were performed using a 3T MR scanner. Both black blood imaging and bright blood cine acquisitions were performed. Quantification of stroke volume (SV) and shunting volume were calculated using a stack of short-axis cine images. Additional 4D (three-spatial dimensions plus time)-TRAK (time-resolved MR angiography with keyhole) sequences were conducted in patient 2 to verify other vasculature abnormality. Black blood images clearly depicted the course of the ductus from the descending aorta to the pulmonary artery in all three dogs. Morphological evaluation of PDA classified patients 1 and 2 as Type 2a and patient 3 as Type 1. Patient 2 was confirmed to have a concurrent persistent left cranial vena cava. Left ventricular SV, right ventricular SV, and left-to-right SV ratio were 12.4 ml, 3.36 ml, and 3.704, respectively, in patient 1; 6.85 ml, 1.22 ml, and 5.60 in the patient 2; and 3.67 ml, 2.14 ml, and 1.702 in patient 3. Findings indicated that cMRI is a feasible method for characterizing the morphology of PDA and extracardiac vasculature anomalies in dogs.

The outstanding sensitivity of high-energetic materials such as cyclotrimethylenetrinitramine (RDX) and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocane (HMX) has prompted efforts by researchers in the production of less sensitive explosives by crystallization without compromising performance. One such endeavor is crystal-size reduction to nano-scales. The optimum operating conditions for producing nano-sized RDX were experimentally determined. Based on these results, computational fluid dynamics modeling and simulations were executed for scale-up purposes and identification of the influence of fluid dynamics, mixing, and heat transfer on crystal growth and production rate on commercial scales. As a result, a commercial plant was designed and operation data from the commercial crystallizers were compared with data obtained from scale-up tasks.

Multilevel hierarchical platforms that combine nano- and microstructures have been intensively explored to mimic superior properties found in nature. However, unless directly replicated from biological samples, desirable multiscale structures have been challenging to efficiently produce to date. Departing from conventional wafer-based technology, new and efficient techniques suitable for fabricating bioinspired structures are highly desired to produce three-dimensional architectures even on nonplanar substrates. Here, we report a facile approach to realize functional nanostructures on uneven microstructured platforms via scalable optical fabrication techniques. The ultrathin form (∼3 μm) of a phase grating composed of poly(vinyl alcohol) makes the material physically flexible and enables full-conformal contact with rough surfaces. The near-field optical effect can be identically generated on highly curved surfaces as a result of superior conformality. Densely packed nanodots with submicron periodicity are uniformly formed on microlens arrays with a radius of curvature that is as low as ∼28 μm. Increasing the size of the gratings causes the production area to be successfully expanded by up to 16 in(2). The "nano-on-micro" structures mimicking real compound eyes are transferred to flexible and stretchable substrates by sequential imprinting, facilitating multifunctional optical films applicable to antireflective diffusers for large-area sheet-illumination displays.

Bias-dependent power distribution network (PDN) impedance is analyzed with respect to MOS capacitor characteristics. The proposed analysis can be used to improve the PDN impedance of 2.5D and 3D ICs.

In this study, we designed a new flex-on-board test vehicle with a 250-µm-pitch coplanar waveguide (CPW) structure for high frequency measurement. The microstirp is 150-um-width and 2-mm-length by Au/Ni surface finished Cu electrode and the ground electrode is designed by 4000-um-width and 2-mm-length. On PCB, 2 CPW patterns are placed with the gap of 0.5 mm. 1 CPW pattern is placed on FPC and aligned in the center of 2 CPWs on PCB by bonding process. The designed PCB has a characteristic impedance of 50 ohm, which leads to low reflection condition. When electric signal faces the different characteristic impedance, some energy of the signal is reflected. Therefore, the PCB may affect the electrical performances due to the signal reflection. So 2 ACFs joints were passed by a 300 MHz to 20 GHz high frequency signals, and S-parameters and physical modelling were performed to characterize transmission property. The S-parameters are assessed by a vector network analyzer (VNA) and microprobe tips. The microprobe tips can evaluate the electrical performances for the ACF. The SMA connector has parasitic elements, which results in accurate measurement result in GHz range. Thus, microprobe tips are used for the electrical performance evaluation instead of the SMA connector. And by extraction of the bare measured FPC and PCB property, only 1 ACF joint insertion loss property was achieved. From the obtained S-parameter, we converted to a resistance (R) to compare the electrical loss by the ACF. During the conversion, the insertion loss, S21, is directly converted to the resistance from 300 MHz to 20 GHz.

Alzheimer's disease (AD), which is the most major cause of dementia, is a progressive neurodegenerative disease that affects cognitive functions. Even though the prevalence of AD is continuously increasing, few drugs including cholinesterase inhibitors and N-methyl D-aspartate-receptor antagonists were approved to treat AD. Because the clinical trials of AD drugs with single targets, such as β-amyloid and tau, have failed, the development of multi-target drugs that ameliorate many of the symptoms of AD is needed. Thus, recent studies have investigated the effects and underlying mechanisms of herbal formulae consisting of various herb combinations used to treat AD. This review discusses the results of clinical and nonclinical studies of the therapeutic efficacy in AD and underlying mechanisms of the herbal formulae of traditional Oriental medicines and bioactive compounds of medicinal plants.

Calculating or predicting the harvest yield of crops in agriculture has been one of its most important techniques. Smart farms, with the power of IoT, provide invaluable information such as real-time environment data such as temperature, humidity, etc. However, there are situations where not all data can be sent over the internet due to private reasons. In this paper, we propose a scalable data analysis framework: the edges preprocess and analyze the private data and send the results to server, and the server gathers and accumulates the results to estimate and predict the total harvest yield. Based on the results obtained from a real tomato farm, error rate is comparable to the one performed at the server only, but the number of features is reduced significantly.

Recently, the number of high-definition media devices such as 8K ultra high-definition (UHD) TV and virtual reality (VR) is rapidly increasing. These multimedia systems require higher data rates for high resolution and versatility. With this increasing technical trend, high-speed connectors and cables are also becoming important. In this paper, we propose a highspeed connector that can transmit high-speed media data. The previous connectors have focused only on a physical connection and a mechanical reliability. However, as the data rate is increased, electrical performances of the connector have also become highly important. Therefore, signal integrity (SI) analysis for insertion loss, attenuation-to-crosstalk ratio (ACR), and impedance mismatch become essential for the high-speed connector. For verification, the 3D EM simulation tool is used to compare the performance of the previous and proposed connector. In conclusion, the proposed high-speed connector has better electrical performances than that of the previous connector.

Two conventional methods, the nominal stress method and the hot spot stress method, are examined for the fatigue assessment of a steel box girder bridge while considering the effect of the modeling options on the estimated fatigue life. Two analytical models, a simplified global analytical model and a refined local finite element analytical model, are developed for the evaluation of the stress ranges induced by a fatigue truck. The field tests are conducted for validating the analytical models as well as for direct fatigue assessment via an ambient vibration test. The local modeling options that are examined are the inclusion of the fillet weld itself in the refined analytical model and the mitigation of the concentrated stress at the web plate, considering stress dispersion over the width of the attachment. The fatigue life is estimated for three different nonexceedance probabilities, considering different partial factors according to the accuracy of the analysis method as well as the reliability of the estimated fatigue loading for a specific bridge site. Through a comparative analysis, the potential differences in estimated fatigue lives according to the assessment methods and the modeling options are quantitatively discussed.

The effective control of the zeroth order diffraction efficiency in phase gratings is a key technique that enables implementation of high-performance optical elements. An interesting and unexplored application is in the field of phase mask interference lithography, which uses a conformal grating to generate periodic 3D nanopatterns by the optically formed Talbot image. A good understanding of the influence of phase and diffraction on the Talbot image is necessary for achieving rational design of 3D nanopatterns, especially in the regime where the grating periodicity is close to the wavelength and where scalar treatments fail to accurately capture the phase optics. The ability to precisely control diffraction and interference in this regime is illustrated by tuning the grating height in the phase mask up to values that exceed a full phase cycle. These results highlight a powerful degree of freedom and solid guidelines for controlling the structural resolution of optically generated 3D nanopatterns.

An ROC (Receiver Operating Characteristic) curve is a popular tool in the classification of two populations. The nonparametric additive model is used to construct a classifier which is estimated by maximizing the U-statistic type of empirical AUC (Area Under Curve). In particular, the sparsity situation is considered in the sense that only a small number of variables is significant in the classification, so it is demanded that lots of noisy variables will be removed. Some theoretical result on the necessity of variable selection under the sparsity condition is provided since the AUC of the classifier from maximization of empirical AUC is not guaranteed to be optimal. To select significant variables in the classification, the grouped lasso which has been widely used when groups of parameters need to be either selected or discarded simultaneously is used. In addition, the performance of the proposed method is evaluated by numerical studies including simulation and real data examples compared with other existing approaches.

An efficient method for constructing multiple candidate finite element (FE) models which are consistent with the measured dynamic properties of a civil structure is presented. A parameterised sensitivity-based FE model updating method was developed to permit a feasible FE model set for the target structure to be produced. In this method, an aggregated multi-objective function, which is defined by the weighted sum of the error functions, is parameterised by its relative weighting factors. By introducing multiple parameter sets for the weighting factors, a number of optimal updated FE models are produced that permit both the natural frequency errors and mode shape errors to be simultaneously minimised. The effectiveness of the proposed method is illustrated by an example using an existing cable-stayed bridge. The findings show that error-minimised, well-distributed FE models can be obtained in terms of modal frequency errors and mode shape errors. The high quality of the candidate model sets is also verifie...

Ghrelin, which has many important physiological roles, such as stimulating food intake, regulating energy homeostasis, and releasing insulin, has recently been studied for its roles in a diverse range of neurological disorders. Despite the several functions of ghrelin in the central nervous system, whether it works as a therapeutic agent for neurological dysfunction has been unclear. Altered levels and various roles of ghrelin have been reported in Alzheimer's disease (AD), which is characterized by the accumulation of misfolded proteins resulting in synaptic loss and cognitive decline. Interestingly, treatment with ghrelin or with the agonist of ghrelin receptor showed attenuation in several cases of AD-related pathology. These findings suggest the potential therapeutic implications of ghrelin in the pathogenesis of AD. In the present review, we summarized the roles of ghrelin in AD pathogenesis, amyloid beta (Aβ) homeostasis, tau hyperphosphorylation, neuroinflammation, mitochondrial deficit, synaptic dysfunction and cognitive impairment. The findings from this review suggest that ghrelin has a novel therapeutic potential for AD treatment. Thus, rigorously designed studies are needed to establish an effective AD-modifying strategy.

The load carrying capacity of a composite open-top steel box girder bridge was evaluated, based on a reliability-based method, and potential differences from conventional approaches were evaluated. A practical analysis model was utilized in evaluating the Rating Factor (RF) after verification with a rigorous full finite element analysis model with solid and plate elements. The accuracy of the analysis models was validated in terms of displacements and distribution factors through static loading tests. Dynamic effects were also estimated from the dynamic loading tests. The load factors, proposed for the purpose of evaluation based on recently accumulated statistical data, were utilized in evaluating RF. The RFs were evaluated for maximum positive flexure, negative flexure, and shear regions along the bridge. The calculated RF with the load factors for evaluation purposes was higher by 35% than that with design load factors. The proposed method also produces a 29% increase in RF compared to the conventional allowable stress design approach. Consequently, the proposed reliability-based procedure would be expected to permit a more economical assessment of bridge performance to be made.

We propose, for the first time, an explicit semiconductor physics-based through-silicon via (TSV) capacitance–voltage (CV) model. The effect of TSV CV hysteresis is demonstrated in the model, and the TSV capacitance is modeled with respect to dc bias voltage and the dimension of the TSV. The proposed model is verified by comparison to the measurement results. The effect of hysteresis in the model correlates well with the measurement results. This model can be utilized in a circuit level simulation to expand the possible application of the model to, but not limited to, hierarchical power distribution network impedance analysis, RC delay analysis, input–output power consumption analysis, and crosstalk and eye diagram simulation in any 3-D-IC systems using TSVs.

A reduction in concrete compressive strength is detected in the main tower of a suspension bridge. Since this strength is below the design strength, structural safety assessment is required. Ambient vibration tests (AVTs) were performed to identify current dynamic of the bridge with 56 dense installation point of accelerometers. Manual tuning method is applied to update analysis model based on measured dynamic properties. As a result, errors between the analysis and measurement of the natural frequencies are reduced from 9% to 4%. Automated model updating method with sensitivity-based optimization is additionally applied to update analysis model. Finally, update model has errors of natural frequencies below 2%. Utilizing the updated model, structural safety assessment is performed considering live load, wind load and seismic load.

An effective optimization method is introduced for the finite element model update of cable- supported bridges. When typical model update methods are applied, there are some difficulties in solving the optimization problem such as local, pre-matured, non-satisfactory solutions due to the large number of updating parameters. Thus, in order to solve the minimization problem effectively, we adopt a large scale global optimization technique which can utilize several algorithms simultaneously. The proposed method is based on the Multiple Offspring Sampling (MOS) framework in which multiple optimization algorithms including genetic algorithms and particle swarm optimization are dynamically combined to produce the global optimal solution. The application example of an existing suspension bridge shows that the proposed method can be effective to update dynamic finite element models.

Motivated by the increasing market demand for the high performance mobile devices, both the data rate and the number of pin of mixed-signal systems keep on increasing to realize multifunctional yet compact system designs. With this ascending technical trend, many signal integrity (SI) and power integrity (PI) problems such as ISI, jitter, crosstalk, simultaneous switching noise (SSN) have arisen that need to be thoroughly analyzed and tested. In order to accurately monitor the data signals of LPDDR4, a carefully designed test interposer considering such factors as impedance matching, minimization of skew and crosstalk needs to be proposed. In this paper, a novel test interposer scheme composed of a test interposer and silicone rubber sheets is proposed for LPDDR4 memory test. Through a series of simulations and measurements, we experimentally verify the proposed structures in time and frequency domains, and prove their accuracy and practicality.

The methodology suggested in this research provides the great possibility of creating nanostructures composed of various materials, such as soft polymer, hard polymer, and metal, as well as Si. Such nanostructures are required for a vast range of optical and display devices, photonic components, physical devices, energy devices including electrodes of secondary batteries, fuel cells, solar cells, and energy harvesters, biological devices including biochips, biomimetic or biosimilar structured devices, and mechanical devices including micro- or nano-scale sensors and actuators.

This study compared rates of cervical cancer screening and acute care (primary or gynecological) visits among women with and without a diagnosis of psychosis, substance use disorder, bipolar disorder or mania, or depression.Using data about women (N=105,681) enrolled in Maryland's Medicaid program in fiscal year 2005, the authors constructed logistic models with cancer screening and acute care visits as dependent variables and serious mental illness flags as independent variables. Covariates were age, race, geography, Medicaid eligibility category, and sexually transmitted diseases. The logistic model of cervical cancer screening outcomes was repeated with acute care visits as a covariate.Women with psychosis (N=4,747), bipolar disorder or mania (N=3,319), or depression (N=5,014) were significantly (p.05) more likely than women in a control group without such disorders (N=85,375) to receive cancer screening (adjusted odds ratio (AOR) range=1.46-1.78) and to have associated acute care visits (AOR range=1.45-2.15). Compared with those in the control group, women with a substance use disorder, with (N=1,104) or without (N=6,122) psychosis, demonstrated reduced odds of cancer screening (AOR=.80) but similar odds of acute care visits (AOR=1.04). Acute care visits were strongly correlated with cancer screens. Genital cancer prevalence did not significantly differ among diagnostic groups.In Maryland Medicaid, the odds of cancer screening and related acute care visits were greater for women with major mental disorders compared with women in the control group. For women with substance use disorders, however, screening was reduced and acute care visits were similar compared with women in the control group. Providers should encourage and support their patients with substance use disorders to increase use of preventive care services by primary care physicians and gynecologists.

When high dimensional microarray data is given, it is of interest to select significant genes by controlling a given level of Type-I error. One popular way to control the level is the false discovery rate (FDR). This paper considers gene selection based on the local false discovery rate. In most of the previous studies, the null distribution of gene expression is commonly assumed to be a normal distribution. However, if the null distribution has heavier tail than that of normal, there may exist too many false discoveries leading to the failure of controlling the given level of FDR. We propose a novel procedure which enriches a class of null distribution based on a mixture of normals. We present simulation studies to show that our proposed procedure is less sensitive to variation of null distribution than local false discovery rate with a single normal for the null. We also provide real example of gene expression profiles of antigen-specific human CD8+ T-lymphocytes treated with cytokine Interleukin-2 (IL-2) and Interleukin-15 (IL-15) for comparison.

We survey some recent work in high dimensional multiple testing estimation and other multivariate inference problems depending on random matrices and graphical problems. Different approaches to these problems are explored featuring classical procedures like the Benjamini-Hochberg multiple tests, empirical Bayes and Bayes tests and estimates and use of shrinkage as a major method in estimation. The choice of topics reflects to some extent our taste and interests.

For high-speed package testing, conductive rubber contactors become more and more promising because of its excellent RF performance. For electrical characteristic analysis of the conductive rubber contactor, the lumped equivalent circuit model of conductive rubber contactor based on its physical dimension and structure is proposed and verified with 3D field and SPICE simulation.

In this paper, an active connector is designed and simulated for high speed serial link interconnection. The connector design consists of three main parts; plug, receptacle, and paddle board. For achieving high bandwidth performance, the key difference of the proposed connector, comparison to the general connector structure, is that the active equalizer is integrated on the paddle board. The connector model is designed and simulated for this study, and the result shows this proposed connector structure is good for high bandwidth interconnection up to 20 Gbps.

This paper reports a new type of transmitting mode electrochromic device that uses the high-contrast electrochromism of poly(3,4-ethylenedioxythiophene) (PEDOT) and operates at long-wavelength infrared (8–12 μm) . To maximize the transmittance contrast and transmittance contrast ratio of the device for thermal camouflage, we control the thickness of the thin PEDOT layer from 25 nm to 400 nm and develop a design of grid-type counter electrodes. The cyclability can be greatly improved by selective deposition of the PEDOT film on grid electrodes as an ion storage layer without any loss of overall transmittance. The device with optimized architectures shows a high transmittance contrast ratio of 83 % at a wavelength of 10 μm with a response rate under 1.4 s when alternating voltage is applied. Captured images of an LED lamp behind the device prove the possibility of active, film-type camouflage against thermal detection. Electronic supplementary material The online version of this article (doi:10.1186/s40580-015-0051-9) contains supplementary material, which is available to authorized users.

The methodology suggested in this research provides the great possibility of creating nanostructures composed of various materials, such as soft polymer, hard polymer, and metal, as well as Si. Such nanostructures are required for a vast range of optical and display devices, photonic components, physical devices, energy devices including electrodes of secondary batteries, fuel cells, solar cells, and energy harvesters, biological devices including biochips, biomimetic or biosimilar structured devices, and mechanical devices including micro- or nano-scale sensors and actuators.

The methodology suggested in this research provides the great possibility of creating nanostructures composed of various materials, such as soft polymer, hard polymer, and metal, as well as Si. Such nanostructures are required for a vast range of optical and display devices, photonic components, physical devices, energy devices including electrodes of secondary batteries, fuel cells, solar cells, and energy harvesters, biological devices including biochips, biomimetic or biosimilar structured devices, and mechanical devices including micro- or nano-scale sensors and actuators.

High-resolution anatomical and functional images can be acquired using high- andultrahigh-field magnetic resonance imaging (MRI) systems. An increase in the mainmagnetic field strength results in high resolution but suffers from thedisadvantage of field nonuniformity in the radio frequency (RF). To overcome thisRF field inhomogeneity, parallel RF transmission system and sensitivity encodingare widely used. Our experimental results showed that the best signal intensity was in transmit andreceive mode head coil, except for the T2-weighted fast field echo (FFE). The bestsignal-to-noise ratio (SNR) was in the 32-channel head coil. In general, multiple-channel coils have been known as more efficient materials interms of SNR. However, they may not be as important in experiments where intensityis an important factor. Therefore, a suitable coil should be selected using apulse sequence.