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The purpose of this study was to generate the PET images with high signal-to-noise ratio (SNR) acquired for typical scan durations (H-PET) from short scan time PET images with low SNR (L-PET) using deep learning and to evaluate the effect of scan time on the quality of predicted PET image. A convolutional neural network (CNN) with a concatenated connection and residual learning framework was implemented. PET data from 27 patients were acquired for 900 s, starting 60 minutes after the intravenous administration of FDG using a commercial PET/CT scanner. To investigate the effect of scan time on the quality of the predicted H-PETs, 10 s, 30 s, 60 s, and 120 s PET data were generated by sorting the 900 s LMF data into the LMF data acquired for each scan time. Twenty-three of the 27 patient images were used for training of the proposed CNN and the remaining four patient images were used for test of the CNN. The predicted H-PETs generated by the CNN were compared to ground-truth H-PETs, L-PETs, and filtered L-PETs processed with four commonly used denoising algorithms. The peak signal-to-noise ratios (PSNRs), normalized root mean square errors (NRMSEs), and average regionof- interest (ROI) differences as a function of scan time were calculated. The quality of the predicted H-PETs generated by the CNN was superior to that of the L-PETs and filtered L-PETs. Lower NRMSEs and higher PSNRs were also obtained from predicted H-PETs compared to the L-PETs and filtered L-PETs. ROI differences in the predicted H-PETs were smaller than those of the L-PETs. The quality of the predicted H-PETs gradually improved with increasing scan times. The lowest NRMSEs, highest PSNRs, and smallest ROI differences were obtained using the predicted H-PETs for 120 s. Various performance test results for the proposed CNN indicate that it is possible to generate H-PETs from neuro FDG L-PETs using the proposed CNN method, which might allow reductions in both scan time and injection dose.

For improving self-heating effects (SHEs) in gate-all-around metal-oxide-semiconductor field-effect transistors (GAA MOSFETs), hetero-gate-dielectric (HGD) is utilized. The HGD consists of hafnium dioxide (HfO2) and silicon dioxide (SiO2), which has high thermal conductivity, hence SHEs are improved. In order to validate the HGD, technology computer-aided design (TCAD) simulation is performed through Synopsys Sentaurus three-dimensional (3D) tool. As a result, when the HGD is adopted in GAA MOSFETs, SHEs can be significantly improved from 498 K to 415 K. In addition, suppression of gate current, more than 2 orders, is also achieved because of bigger bandgap of SiO2 in HGD. Consequently, this structure takes advantage of higher thermal conductivity and bigger bandgap of SiO2, and higher permittivity of HfO2 for improving SHEs and gate leakage current.

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder caused by the loss of motor neurons from the brain and spinal cord. The ALS community has made remarkable strides over three decades by identifying novel familial mutations, generating animal models, elucidating molecular mechanisms, and ultimately developing promising new therapeutic approaches. Some of these approaches reduce the expression of mutant genes and are in human clinical trials, highlighting the need to carefully consider the normal functions of these genes and potential contribution of gene loss-of-function to ALS. Here, we highlight known loss-of-function mechanisms underlying ALS, potential consequences of lowering levels of gene products, and the need to consider both gain and loss of function to develop safe and effective therapeutic strategies.

Composite honeycomb sandwich structure is widely used for aircraft structures such as control surfaces, radomes, engine cowls, and aircraft interior structure because of its lightweight and high strength characteristics. One of the disadvantages of honeycomb sandwich structure is that they are prone to fluid intrusion. The purpose of this study is to determine if the structural properties of honeycomb core are affected by contact with a fluid. The test specimens were manufactured of fiberglass prepreg for the facesheets and Nomex® honeycomb core for the core material in accordance with ASTM C-365/365M. Test specimens were soaked in several different kinds of fluids, such as aircraft fuel, turbine engine oil, hydraulic fluid, and water for a period of 60 days. Some of specimens were tested right after soaking period ended, and some of them were dried before they were tested. A flatwise compressive test was performed, and the test results were analyzed to determine how the contact with aircraft fluids affected the compressive strength of the Nomex® honeycomb core and how the strength was recovered when the specimens were dry. In addition, the investigation of de-bonding between facesheet and core material after soaking was performed to support the study.

ObjectiveTo investigate the status of the basal forebrain cholinergic system in primary progressive aphasia (PPA) as justification for cholinergic therapy.MethodsA cohort of 36 brains from PPA participants with the neuropathology of Alzheimer disease (PPA-AD, n = 14) or frontotemporal lobar degeneration (PPA-tau, n = 12; PPA-TDP, n = 10) were used for semiquantitative rating of degeneration and gliosis of basal forebrain cholinergic neurons (BFCN). A subpopulation of 5 PPA-AD and 7 control brains underwent detailed analysis of BFCN pathology and cortical cholinergic axonal loss employing immunohistochemical and histochemical methods and stereologic analysis.ResultsSemiquantitatively, 11 (∼80%) PPA-AD participants were rated as having moderate/severe BFCN loss and gliosis, whereas none of the PPA-tau and only 1 (10%) PPA-TDP participant received such a rating. Detailed analysis in the subpopulation of PPA-AD participants revealed substantial tangle formation, loss of BFCN, and degeneration of cortical cholinergic axons. Compared to controls, loss of p75 low affinity neurotrophin receptor-positive BFCN was detected in the PPA-AD participants (p < 0.01). Acetylcholinesterase-positive cholinergic axons in all cortical areas studied displayed loss in PPA-AD (p < 0.005–0.0001). The loss was more severe in the language-dominant left hemisphere and, within the left hemisphere, in language-affiliated cortical areas.ConclusionsOur results demonstrate prominent depletion of BFCN and cortical cholinergic axons in PPA-AD when compared with normal control or other neuropathologic variants of PPA. The demonstration of cholinergic denervation with an anatomy that fits the clinical picture suggests that cholinergic treatment is justified in patients with PPA who have positive AD biomarkers.

In this study, the axial and lateral load-carrying behavior of encased micropile (MP) with perforated configuration was investigated. The perforated casing adopted in this study was a casi...

Purpose This study was to develop a convolutional neural network (CNN) model with a residual learning framework to predict the full-time 18F-florbetaben (18F-FBB) PET/CT images from corresponding short-time scans. Methods In this retrospective study, we enrolled 22 cognitively normal subjects, 20 patients with mild cognitive impairment, and 42 patients with Alzheimer disease. Twenty minutes of list-mode PET/CT data were acquired and reconstructed as the ground-truth images. The short-time scans were made in either 1, 2, 3, 4, or 5 minutes. The CNN with a residual learning framework was implemented to predict the ground-truth images of 18F-FBB PET/CT using short-time scans with either a single-slice or a 3-slice input layer. Model performance was evaluated by quantitative and qualitative analyses. Additionally, we quantified the amyloid load in the ground-truth and predicted images using the SUV ratio. Results On quantitative analyses, with increasing scan time, the normalized root-mean-squared error and the SUV ratio differences between predicted and ground-truth images gradually decreased, and the peak signal-to-noise ratio increased. On qualitative analysis, the predicted images from the 3-slice CNN model showed better image quality than those from the single-slice model. The 3-slice CNN model with a short-time scan of at least 2 minutes achieved comparable, quantitative prediction of full-time 18F-FBB PET/CT images, with adequate to excellent image quality. Conclusions The 3-slice CNN model with a residual learning framework is promising for the prediction of full-time 18F-FBB PET/CT images from short-time scans.

This study aims to improve the efficiency of task switching in hospital laboratories. In a laboratory, several medical technicians perform multiple tasks. Technicians are not aware of the marginal amount of time it takes to switch between tasks, and this accumulation of lost minutes can cause the technician to worry more about the remaining working time than work quality. They rush through their remaining tasks, thereby rendering their work less efficient. For time optimization, we identified work changeover times to help maintain the work quality in the laboratory while reducing the number of task switching instances. We used the turnaround time (TAT) compliance rate of emergency room samples as an indicator to evaluate laboratory performance and the number of task switching instances as an index of the task performer perspective (TPP). We experimented with a monitoring system that populates the time for sample classification according to the optimal time for task switching. Through the proposed methodology, we successfully reduced not only the instances of task switching by 10% but also the TAT non-compliance rate from 4.97 to 2.66%. Consequently, the introduction of new methodology has greatly increased work efficiency.

Metal gate technology is one of the most important methods used to increase the low on-current of tunnel field-effect transistors (TFETs). However, metal gates have different work-functions for each grain during the deposition process, resulting in work-function variation (WFV) effects, which means that the electrical characteristics vary from device to device. The WFV of a planar TFET, double-gate (DG) TFET, and electron-hole bilayer TFET (EHBTFET) were examined by technology computer-aided design (TCAD) simulations to analyze the influences of device structure and to find strategies for suppressing the WFV effects in TFET. Comparing the WFV effects through the turn-on voltage (Vturn-on) distribution, the planar TFET showed the largest standard deviation (&sigma, Vturn-on) of 20.1 mV, and it was reduced by &minus, 26.4% for the DG TFET and &minus, 80.1% for the EHBTFET. Based on the analyses regarding metal grain distribution and energy band diagrams, the WFV of TFETs was determined by the number of metal grains involved in the tunneling current. Therefore, the EHBTFET, which can determine the tunneling current by all of the metal grains where the main gate and the sub gate overlap, is considered to be a promising structure that can reduce the WFV effect of TFETs.

In this paper, analysis and optimization of surrounding channel nanowire (SCNW) tunnel field-effect transistor (TFET) has been discussed with the help of technology computer-aided design (TCAD) simulation. The SCNW TFET features an ultra-thin tunnel layer at source sidewall and shows a high on-current (ION). In spite of the high electrical performance, the SCNW TFET suffers from hump effect which deteriorates subthreshold swing (S). In order to solve the issue, an origin of hump effect is analyzed firstly. Based on the simulation, the transfer curve in SCNW TFET is decoupled into vertical- and lateral-BTBTs. In addition, the lateral-BTBT causes the hump effect due to low turn-on voltage (VON) and low ION. Therefore, the device design parameter is optimized to suppress the hump effect by adjusting thickness of the ultra-thin tunnel layer. Finally, we compared the electrical properties of the planar, nanowire and SCNW TFET. As a result, the optimized SCNW TFET shows better electrical performance compared with other TFETs.

3D NAND flash memory has enhanced its areal density by more than 50% per year by virtue of the aggressive development of 3D WL stacking technology for the recent three consecutive years [1]–[3]. Also storage market still requires more bits for diverse digital applications. [4]

As a combined foundation, micropiled rafts under compressive loads show the load-sharing behavior between raft and micropiles. The load carrying and sharing behaviors of micropiled rafts installed with inclined condition would become further complicated as a result of the coupled influences of group and inclined configurations. In this study, the 3D finite element analyses were performed to investigate the load carrying and sharing behaviors of inclined micropiled rafts. Changes in foundation configurations, including micropile inclination angle and spacing, were considered in the analyses. The load carrying capacity of micropiled rafts varied with the inclination angle of micropiles and the proportion of load carried by inclined micropiles was larger than for vertically installed condition. The values of the load sharing ratio αp for the inclined condition were obtained and analyzed. The normalized load-sharing model for inclined micropiled rafts was proposed with the modified load capacity interaction factor and design equations as a function of micropile configuration and inclination angle. Case studies were selected from the literature and adopted to compare with the calculated results using the proposed method. The calculated results were in reasonable agreement with measured load sharing ratios.

In the present study, the vertical load-carrying behavior of micropile foundations with various configuration conditions was investigated based on results from model load tests. Considered configuration conditions included micropile inclination angle, spacing of micropiles, and types of micropile foundations. The ultimate load capacity of micropiles varied with installation angle, showing an initial increase and peak followed by a gradual decrease with further increase in installation angle. The ultimate load capacity of micropiled rafts was affected by both installation angle and micropile spacing. The load-carrying mechanism of micropiles for the inclined condition was proposed based on the decomposed axial and lateral load and resistance components. Using the proposed load-carrying mechanism and test results obtained in this study, the load capacity ratio for an inclined micropile was proposed. The group effect and interaction effect factors for group micropiles and micropiled rafts were proposed, respectively, all of which can be used to estimate the load-carrying capacity of micropile foundations. Field load tests were conducted and it was seen that estimated results using the proposed method were in good agreement with measured results. Additional comparison with case examples from the literature also confirmed the validity of the proposed method.

In this manuscript, channel area fluctuation (CAF) effects on turn-on voltage (Von) and subthreshold swing (SS) in gate-all-around (GAA) nanowire (NW) tunnel field-effect transistor (TFET) with multi-bridge-channel (MBC) have been investigated for the first time. These variations occur because oblique etching slope makes various elliptical-shaped channels in MBC-TFET. Since TFET is promising candidates to succeed metal-oxide-semiconductor FETs (MOSFET), these variation effects have been compared to MOSFET. Furthermore, Ge homojunction TFET, one of the solutions to increase on-state current in TFET and improve SS also has been simulated using technology computer-aided design (TCAD) simulation. The results would be worth reference for future study about GAA NW TFETs.

The tunnel field-effect transistor (TFET) with surrounding channel nanowire (SCNW) structure promises better performance than the conventional planar TFET in terms of subthreshold swing (SS) and on-current (ION). In spite of the advantages of SCNW TFET, there are some technical issues in the aspects of a hump phenomenon in subthreshold region and a high ambipolar current (IAMB) in off-state. In order to overcome these issues, a novel dual-gate SCNW TFET (DG-SCNW TFET) with differential gate work functions (WFs) and a gate-drain underlap is proposed and studied by using technology computer-aided design (TCAD) simulation. In addition, a hetero-junction with SiGe source is applied to improve the device performance. Finally, it is confirmed that the optimized DG-SCNW TFET shows the remarkable performance comparing with the control device.

In this report, a novel tunnel field-effect transistor (TFET) named &lsquo, F-shaped TFET&rsquo, has been proposed and its electrical characteristics are analyzed and optimized by using a computer-aided design simulation. It features ultra-thin and a highly doped source surrounded by lightly doped regions. As a result, it is compared to an L-shaped TFET, which is a motivation of this work, the F-shaped TFET can lower turn-on voltage (VON) maintaining high on-state current (ION) and low subthreshold swing (SS) with the help of electric field crowding effects. The optimized F-shaped TFET shows 0.4 V lower VON than the L-shaped TFET with the same design parameter. In addition, it shows 4.8 times higher ION and 7 mV/dec smaller average SS with the same VON as that for L-shaped TFET.

The neuropathologic basis of in vivo cortical atrophy in clinical dementia syndromes remains poorly understood. This includes primary progressive aphasia (PPA), a language-based dementia syndrome characterized by asymmetric cortical atrophy. The neurofibrillary tangles (NFTs) and amyloid-s plaques (APs) of Alzheimer's disease (AD) can cause PPA, but a quantitative investigation of the relationships between NFTs, APs and in vivo cortical atrophy in PPA-AD is lacking. The present study measured cortical atrophy from corresponding bilateral regions in five PPA-AD participants with in vivo magnetic resonance imaging scans 7-30 months before death and acquired stereologic estimates of NFTs and dense-core APs visualized with the Thioflavin-S stain. Linear mixed models accounting for repeated measures and stratified by hemisphere and region (language vs. non-language) were used to determine the relationships between cortical atrophy and AD neuropathology and their regional selectivity. Consistent with the aphasic profile of PPA, left language regions displayed more cortical atrophy (P = 0.01) and NFT densities (P = 0.02) compared to right language homologues. Left language regions also showed more cortical atrophy (P < 0.01) and NFT densities (P = 0.02) than left non-language regions. A subset of data was analyzed to determine the predilection of AD neuropathology for neocortical regions compared to entorhinal cortex in the left hemisphere, which showed that the three most atrophied language regions had greater NFT (P = 0.04) and AP densities (P < 0.01) than the entorhinal cortex. These results provide quantitative evidence that NFT accumulation in PPA selectively targets the language network and may not follow the Braak staging of neurofibrillary degeneration characteristic of amnestic AD. Only NFT densities, not AP densities, were positively associated with cortical atrophy within left language regions (P < 0.01) and right language homologues (P < 0.01). Given previous findings from amnestic AD, the current study of PPA-AD provides converging evidence that NFTs are the principal determinants of atrophy and clinical phenotypes associated with AD.

Activation of microglia, the primary mediators of inflammation in the brain, is a major component of gliosis and neuronal loss in a number of age-related neurodegenerative disorders, such as Alzheimer's disease (AD). The role of activated microglia in white matter, and its relationship with cognitive decline during aging are unknown. The current study evaluated microglia densities in the white matter of postmortem specimens from cognitively normal young adults, cognitively normal older adults, and cognitive "SuperAgers," a unique group of individuals over age 80 whose memory test scores are at a level equal to or better than scores of 50-to-65-year-olds. Whole hemisphere sections from cognitively normal old, young, and "SuperAgers" were used to quantify densities of human leukocyte antigen-D related (HLA-DR)-positive activated microglia underlying five cortical regions. Statistical findings showed a significant main effect of group on differences in microglia density where cognitively normal old showed highest densities. No difference between SuperAgers and young specimens were detected. In two autopsied SuperAgers with MRI FLAIR scans available, prominent hyperintensities in periventricular regions were observed, and interestingly, examination of corresponding postmortem sections showed only sparse microglia densities. In conclusion, activated microglia appear to respond to age-related pathologic changes in cortical white matter, and this phenomenon is largely spared in SuperAgers. Findings offer insights into the relationship between white matter neuroinflammatory changes and cognitive integrity during aging.

For improving self-heating effect (SHE) in Ge vertically stacked gate-all-around (GAA) nanowire (NW) p-type metal-oxide-semiconductor field-effect transistor (pMOSFET), aluminum oxide (Al2O3, alumina) is utilized for gate dielectric layer. From the high thermal conductivity of Al2O3, SHE is significantly improved. In order to validate the proposed device structure, technology computer-aided design simulation is performed through Synopsys Sentaurus three-dimensional tool. As a result, when Al2O3 is incorporated in Ge vertically stacked GAA NW pMOSFET, SHE can be remarkably improved from 534 to 419 K. In addition, the method of simultaneously accomplishing improvement of SHE and low gate leakage current (I gate) have been specifically investigated and proposed with numerous simulation data.

In this paper, a novel tunnel field-effect transistor (TFET) has been demonstrated. The proposed TFET features a SiGe channel, a fin structure and an elevated drain to improve its electrical performance. As a result, it shows high-level ON-state current (ION) and low-level OFF-state current (IOFF), ambipolar current (IAMB). In detail, its ION is enhanced by 24 times more than that of Si control group and by 6 times more than of SiGe control group. The IAMB can be reduced by up to 900 times compared with the SiGe control group. In addition, technology computer-aided design (TCAD) simulation is performed to optimize electrical performance. Then, the benchmarking of ON/OFF current is also discussed with other research group&rsquo, s results.

The main challenge for tunnel field-effect transistors (TFETs) is achieving high on-current (Ion) and low subthreshold swing (SS) with reasonable ambipolar characteristics. In order to address these challenges, Ge-channel heterostructure TFET with Si source and drain region is proposed, and its electrical characteristics are compared to other TFET structures. From two-dimensional (2-D) device simulation results, it is confirmed that the Si/Ge heterostructure source junction improves Ion and SS characteristics by using the direct band-to-band tunneling current. Furthermore, the proposed structure shows suppressed ambipolar behavior since the Ge/Si heterostructure is used at the drain junction.

Peptidyl-prolyl cis/trans isomerase NIMA-interacting 1 (PIN1) induces conformational and functional changes to numerous key signaling molecules following proline-directed phosphorylation and its deregulation contributes to disease, particularly cancer. PIN1 is overexpressed in breast cancer, promoting cell proliferation and transformation in collaboration with several oncogenic signaling pathways, and is correlated with a poor clinical outcome. PIN1 level is also increased in certain gynecological cancers such as cervical, ovarian, and endometrial cancers. Although women with breast cancer are at risk of developing a second primary gynecological malignancy, particularly of the endometrium and ovary, the common oncogenic signaling pathway mediated by PIN1 has not been noted to date. This review discusses the roles of PIN1 in breast tumorigenesis and gynecological cancer progression, as well as the clinical effect of targeting this enzyme in breast and gynecological cancers.

In the present study, a CPT-based p-y analysis method was proposed for offshore mono-piles embedded in sands. Static and cyclic loading conditions were both taken into account for the proposed method. The continuous soil profiling capability of CPT was an important consideration for the proposed method, where detailed soil profile condition with depth can be readily incorporated into the analysis. The hyperbolic function was adopted to describe the non-linear p-y curves. For the proposed hyperbolic p-y relationship, the ultimate lateral soil resistance pu was given as a function of the cone resistance, which is directly introduced into the analysis as an input data. For cyclic loading condition, two different cyclic modification factors were considered and compared. Case examples were selected to check the validity of the proposed CPT-based method. Calculated lateral displacements and bending moments from the proposed method were in good agreement with measured results for lateral displacement and bending moment profiles. It was observed the accuracy of calculated results for the conventional approach was largely dependent on the selection of friction angle that is to be adopted into the analysis.

In conventional LEDs, a mesa-structure is usually used and it causes the current to be overcrowded in a specific region. We propose a novel structure of GaN-based LED to overcome this problem. In order to distribute the current in an active region, a spreading pad is inserted at the p-type region in the GaN based LED device. The inserted spreading pad helps the current flow because it is more conductive than the p-type GaN layer. By performing electrical and optical simulations, the effects of the spreading pad insertion are confirmed. The results of electrical simulation show that the current spreads more uniformly and more radiative recombination is produced as well. Moreover, from the optical simulation, it is revealed that the ITO is less absorptive material than p-GaN if the condition of specific wavelength sources is satisfied. Considering all of the results, we can conclude that the luminescent power is enhanced by the spreading pad.

This study investigated the presence of combined pathologies in a large cohort of autopsies that show a primary pathologic diagnosis of phosphorylated 43-kDa TAR DNA-binding protein (FTLD-TDP), the majority of which portrayed clinical phenotypes consistent with primary progressive aphasia or behavioral variant frontotemporal dementia (bvFTD). Thirty-eight cases with FTLD-TDP (30 type-A and 8 type-C) were identified to determine characteristic differences between cases with and without combined pathologies. Findings indicated that combined pathologies co-occur with FTLD-TDP type-A at a high frequency (50%)-greater than when compared to FTLD-TDP type-C cases (12.5%). Those with FTLD-TDP type-A and combined pathologies showed significantly longer lifespans (p

Many aerospace and automotive parts are made from advanced composite materials for increased performance and weight savings. Composite tooling is used to manufacture composite parts when they are manufactured by the original equipment manufacturer, but this tooling is typically not available in an aircraft repair station or automotive repair shop. The authors have developed a method using laser-scanning technology to design composite tooling that could be used to manufacture replacement parts or repair damage to a structure. The scanning system is portable and could be used to scan components while they are on the aircraft or vehicle or when they are removed. The laser scanner will produce a solid model and CAD/CAM software will be used to develop the tool geometry and program tool paths for CNC machining.

In order to overcome small current drivability of a tunneling field-effect transistor (TFET), a TFET using Schottky barrier (SBTFET) is proposed. The proposed device has a metal source region unlike the conventional TFET. In addition, dopant segregation technology between the source and channel region is applied to reduce tunneling resistance. For TFET fabrication, spacer technique is adopted to enable self-aligned process because the SBTFET consists of source and drain with different types. Also the control device which has a doped source region is made to compare the electrical characteristics with those of the SBTFET. From the measured results, the SBTFET shows better on/off switching property than the control device. The observed drive current is larger than those of the previously reported TFET. Also, short-channel effects (SCEs) are investigated through the comparison of electrical characteristics between the long- and shortchannel SBTFET .

Current crowding problem can worsen the internal quantum efficiency and the negative-voltage ESD of InGaN-based LEDs. In this paper, by using photon emission microscope and thermal emission microscope measurement, we confirmed that the electric field and the current of the InGaN-based LED sample are crowded in specific regions where the distance between p-type metal contact and n-type metal contact is shorter than other regions. To improve this crowding problem of electric field and current, modified metal contact geometry having uniform distance between the two contacts is proposed and verified by a numerical simulation. It is confirmed that the proposed structure shows better current spreading, resulting in higher internal quantum efficiency and reduced reverse leakage current.

Control of threshold voltage (V T ) by ground-plane (GP) technique for planar tunnel fieldeffect transistor (TFET) is studied for the first time using TCAD simulation method. Although GP technique appears to be similarly useful for the TFET as for the metal-oxide-semiconductor field-effect transistor (MOSFET), some unique behaviors such as the small controllability under weak ground doping and dependence on the dopant polarity are also observed. For V T -modulation larger than 100 mV, heavy ground doping over 1×1020 cm -3 or back biasing scheme is preferred in case of TFETs. Polarity dependence is explained with a mechanism similar to the punch-through of MOSFETs. In spite of some minor differences, this result shows that both MOSFETs and TFETs can share common V T -control scheme when these devices are co-integrated.

In this study, the effects of back-gate bias on the subthreshold swing (S) of a tunnel field-effect transistor (TFET) were discussed. The electrostatic characteristics of the back-gated TFET were obtained using technology computer-aided design (TCAD) simulation and were explained using the concepts of turn-on and inversion voltages. As a result, S decreased, when the back-gate voltage increased, this behavior is attributed to the resultant increase in inversion voltage. In addition, it was found that the on&ndash, off current ratio of the TFET increased with a decrease in S due to the back-gate voltage.

Micropile technology has evolved continuously since its instruction by Fernando Lizzi in the 1950s. The effects of group micropile have been researched by many researchers. The effects of group micropile differ and change with pile length, pile spacing (S), pile angle () and pile embedded conditions. In the present study, the effects of resistance increase and settlement reduction from micropiles were investigated through a series of axial load tests. For the study, axial load tests were performed using mat, group micropiles and micropiled-raft (MPR) in various pile spacing and pile angle conditions. As the result, the effects of resistance of micropiled-raft were 80% (3D) to 110% (7D) of the total resistance of mat and group micropile. The effects of settlement restraint of micropiled-raft were 20% (S

The light-emitting diode (LED) with an improved hole injection and straightforward process integration is proposed. p-type GaN direct hole injection plugs (DHIPs) are formed on locally etched multiple-quantum wells (MQWs) by epitaxial lateral overgrowth (ELO) method. We confirm that the optical output power is increased up to 23.2% at an operating current density of 100 A/cmsup2/sup. Furthermore, in order to identify the origin of improvement in optical performance, the transient light decay time and light intensity distribution characteristics were analyzed on the DHIP LED devices. Through the calculation of the electroluminescence (EL) decay time, internal quantum efficiency (IQE) is extracted along with the recombination parameters, which reveals that the DHIPs have a significant effect on enhancement of radiative recombination and reduction of efficiency droop. Furthermore, the mapping PL reveals that the DHIP LED also has a potential to improve the light extraction efficiency by hexagonal pyramid shaped DHIPs.

Grabcut is an efficient image segmentation technique which facilitates easy user interaction by locating a rectangular bounding box to include the foreground objects. However, when the foreground objects exhibit similar colors to that of the background, it often fail to work to accurately classify the pixels within the interior region of the bonding box. In this paper, we propose an adaptive region of interest selection algorithm for Grabcut-based image segmentation. We first obtain an initial segmentation result by performing the Grabcut on the depth image aligned to an input color image. Then we shrink and enlarge the depth segmentation mask by using the erosion and dilation operations. We regard the outside of the enlarged mask as background pixels and regard the interior of the shrunken mask as foreground pixels. The remaining pixels are classified into the foreground objects and the background by performing the Grabcut using the four-channel Gaussian mixture model of RGB colors and depth. Experimental results show that the proposed algorithm effectively suppress the false detection of objects and improves the segmentation performance compared with the existing algorithms by adaptively selecting the region of interest.

Tunneling Field Effect Transistors (TFETs) are considered as a candidate for low power applications. However, most of TFETs have been researched on only for long channels due to the misalignment problem that occurs during the source/drain doping process in device fabrication. Thus, a new method is proposed for the fabrication of TFETs in nanoscale regions. This proposed fabrication process does not need an additional mask to define the source/drain regions, and makes it possible to form a self-aligned source/drain doping process. In addition, through TCAD simulation, the electrical characteristics of a TFET with dopant engineering and a rounded gate edge shape for a higher on/off current ratio were investigated. As a result, the TFET showed the properties of a larger on-current, a lower average subthreshold swing (58.5 mV/dec), and a 30-fold smaller leakage current compared to the conventional TFET The TFET with dopant engineering and a rounded gate edge shape can also be fabricated simply through the proposed fabrication process.

In order to extend the conventional low power Si CMOS technology beyond the 20-nm node without SOI substrates, we propose a novel co-integration scheme to build horizontal- and vertical-channel MOSFETs together and verify the idea using TCAD simulations. From the fabrication viewpoint, it is highlighted that this scheme provides additional vertical devices with good scalability by adding a few steps to the conventional CMOS process flow for fin formation. In addition, the benefits of the co-integrated vertical devices are investigated using a TCAD device simulation. From this study, it is confirmed that the vertical device shows improved off-current control and a larger drive current when the body dimension is less than 20 nm, due to the electric field coupling effect at the double-gated channel. Finally, the benefits from the circuit design viewpoint, such as the larger midpoint gain and beta and lower power consumption, are confirmed by the mixed-mode circuit simulation study.

The conventional object segmentation methods often degrade their performance due to the requirement of user interaction and/or the incomplete colour appearance models. In this Letter, the authors propose a novel design method of a colour appearance model for accurate and fully-automatic object segmentation by using saliency maps. The authors initialise the Gaussian mixture models (GMMs) to describe the colour appearance of the foreground objects and the background, respectively, where the mean vectors, covariance matrices, and mixing coefficients are updated adaptively such that more salient pixels have larger weights to update the GMM for the foreground objects while less salient pixels have larger weights to update the GMM for the background, respectively. Experiments are performed on MSRC, iCoseg, and PASCAL datasets and we show that the proposed method outperforms the existing methods quantitatively and qualitatively.

In this work, a tunneling field-effect transistor (TFET) based on heterojunctions of compound and Group IV semiconductors is introduced and simulated. TFETs based on either silicon or compound semiconductors have been intensively researched due to their merits of robustness against short channel effects (SCEs) and excellent subthreshold swing (SS) characteristics. However, silicon TFETs have the drawback of low on-current and compound ones are difficult to integrate with silicon CMOS circuits. In order to combine the high tunneling efficiency of narrow bandgap material TFETs and the high mobility of III-V TFETs, a Type-I heterojunction tunneling field- effect transistor (I-HTFET) adopting Ge-AlxGa1-xAs- Ge system has been optimized by simulation in terms of aluminum (Al) composition. To maximize device performance, we considered a nanowire structure, and it was shown that high performance (HP) logic technology can be achieved by the proposed device. The optimum Al composition turned out to be around 20% (x=0.2). Index Terms—Tunneling field-effect transistor (TFET), Type-I heterojunction, narrow bandgap material, high mobility, simulation, nanowire, high performance (HP) logic technology

As the feature size of the conventional 1T-1C DRAM scales down, difficulties of the fabrication process are increasing and it is becoming harder to keep a constant capacitance value for data storage. Capacitor-less 1T DRAM is a promising candidate for the substitution of the conventional 1T-1C DRAM, but its poor retention time is one of the critical issues in its commercialization. In the selection of a bias condition for 1T DRAM, however, it is impossible to choose a gate bias condition that is suitable for both the "1" and "0" hold state data. In this paper, a split gate structure and hold bias scheme are proposed for the simultaneous improvement of the "1" and "0" data retention characteristics. It was confirmed through numerical simulation that this structure has a more than 3 sec retention time. A vertical gate-all-around split-gate structure and its fabrication method are also suggested to achieve high density, low cost, a higher sensing margin, and a longer retention time.

In this paper, a 3-D NAND Flash memory array having multiple single-crystal Si nanowires is investigated. Device structure and fabrication process are described including the electrical isolation of stacked nanowires. Numerical simulation results focused on NAND Flash memory operation are delivered. Devices and array with stacked bit lines are fabricated, and memory characteristics such as program/erase select gate operation are measured. Array scheme is also discussed for the high-density bit-cost scalable 3-D stacked bit-line NAND Flash memory application.

The connected foundation is an effective structural type of foundation that can improve the sustainability of electrical transmission towers in soft soils to serve as a resilient energy supply system. In this study, the performance of electrical transmission towers reinforced with connected beams was investigated using a series of field load tests. Model transmission tower structures were manufactured and adopted into the tests. Based on the load capacity mobilization and failure mechanism, a criterion to define the load carrying capacity for connected foundation was proposed. It was found that the performance of connected foundation varies with the mechanical property of connection beam. The load capacity and differential settlement increased and decreased, respectively, with increasing connection beam stiffness. Such effect of connection beam was more pronounced as the height of load application point or tower height (z(h)) increases. Based on the load test results, a design model was proposed that can be used to evaluate the sustainable performance and load carrying capacity of connected foundations. Field load tests with prototype transmission tower structure models were conducted to check and confirm the performance of connected foundation and the proposed design method.

A simple method of measurement which can estimate the recombination coefficients and the internal quantum efficiency (IQE) in GaN-based light-emitting diodes (LEDs) has been developed. The proposed method uses optical power decay, which can reflect real operational circumstances. The method, which is based on the electro-luminescence, is expected to extract values of the IQE in GaN-based LEDs effectively.