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Background Postoperative delirium is a challenging complication due to its adverse outcome such as long hospital stay. The aims of this study were: 1) to identify preoperative risk factors of postoperative delirium following knee arthroplasty, and 2) to develop a machine-learning prediction model. Method A total of 3,980 patients from two hospitals were included in this study. The model was developed and trained with 1,931 patients from one hospital and externally validated with 2,049 patients from another hospital. Twenty preoperative variables were collected using electronic hospital records. Feature selection was conducted using the sequential feature selection (SFS). Extreme Gradient Boosting algorithm (XGBoost) model as a machine-learning classifier was applied to predict delirium. A tenfold-stratified area under the curve (AUC) served as the metric for variable selection and internal validation. Results The incidence rate of delirium was 4.9% (n = 196). The following seven key predictors of postoperative delirium were selected: age, serum albumin, number of hypnotics and sedatives drugs taken preoperatively, total number of drugs (any kinds of oral medication) taken preoperatively, neurologic disorders, depression, and fall-down risk (all p https://safetka.connecteve.com. Conclusions A web-based predictive model for delirium after knee arthroplasty was developed using a machine-learning algorithm featuring seven preoperative variables. This model can be used only with information that can be obtained from pre-operative electronic hospital records. Thus, this model could be used to predict delirium before surgery and may assist physician’s effort on delirium prevention.

This paper first presents a 3D integrated high gain rectenna in package with metamaterial (MTM) superstrates for a high efficiency wireless power transfer (WPT) application which operates at 2.45 GHz. The integrated rectenna is composed of 3 layers where the first layer is an MTM superstrate consisting of 4 by 4 MTM unit cells (the size of the unit cell: $\mathrm{27.5}\times \mathrm{27.5}\ \text{mm}^{\mathrm{2}}$ ), the second layer a patch antenna ( $\mathrm{36.1}\times \mathrm{27.9}\ \text{mm}^{2}$ ), and the third layer a rectifier ( $\mathrm{54.2}\times \mathrm{16.3}\ \text{mm}^{\mathrm{2}}$ ). By integrating the MTM superstrate on top of the patch antenna, the gain of the antenna is enhanced due to its focusing capability, resulting in the increase of incident RF power at the rectifier input thereby inducing high output DC power and high end-to-end efficiency. A prototype 3D integrated rectenna is designed, fabricated and characterized. It shows a gain improvement of 5.8 dB compared to a counterpart patch antenna without an MTM superstrate, and a maximum RF-DC conversion efficiency of 63.5% at an input RF power of 10.5 dBm. This results in the improvement of the RF-DC efficiency from 56.8% to 63.5% and the increase of the output DC power from 1.6 mW to 6.35 mW (a factor of 3.97 improvements).

High tibial osteotomy (HTO) is a well-established treatment for medial compartment knee osteoarthritis (OA), which shifts the weight-bearing axis from the medial to the lateral side of the knee. As the adjacent ankle joint may be directly affected by the change in biomechanics, this study aimed to evaluate the change in the intersegmental foot and ankle motion after HTO in patients with genu varum. The study included 24 patients who underwent HTO, and 48 older healthy participants as a control group. Segmental foot kinematics were evaluated using a 3D multisegment foot model, and gait data of temporal and spatial parameters were obtained. After HTO, normalized stride length significantly increased with a tendency for increases in gait speed. In hallux kinematics relative to the forefoot, the sagittal motions of both the patients and the control group were similar throughout the majority of the gait cycle. In forefoot kinematics relative to the hindfoot, the pre-HTO state revealed significant pronation throughout the gait cycle, while the post-HTO state showed a similar position and motion to the control group. In hindfoot kinematics relative to the tibia, coronal motions of the pre-HTO state showed supination throughout the gait cycle, while supination during the stance phase decreased after HTO. Genu varum patients with medial compartment knee OA showed different gait parameters and intersegmental motion during gait when compared with age- and gender-matched controls. The effect of HTO was demonstrated by the normalization of midfoot compensation in patients with genu varum.

Cobalt (Co) ion selective electrode (ISE) has been studied for selective phosphate detection. As the electromotive force (EMF) response of this electrode to phosphate is affected by surrounding pH conditions, it has not been readily utilized for in-situ monitoring. In this work, we present an integrated Co based phosphate and antimony (Sb) based pH sensing system, which enables us to monitor precise phosphorous concentration taking into account a local pH level in aqueous solution. Platinum is used as the reference electrode. An extremely broad sensing range of phosphate concentration with 9 orders of magnitude concentration ranging between $5\times 10^{-3}$ to $5\times 10^{-12}$ M is reported. The sensing sensitive of 5 pM is one of the best reported in this kind of sensors in literature. Also, simultaneous detection of pH and phosphate concentration is presented using integrated wireless Bluetooth module. The total area of the fabricated sensor is 4 cm2.

This paper presents a metamaterial (MTM)-integrated high-gain rectenna for RF sensing and energy harvesting applications that operates at 2.45 GHz, an industry, science, medicine (ISM) band. The novel MTM superstrate approach with a three-layered integration method is firstly introduced for rectenna applications. The integrated rectenna consists of three layers, where the first layer is an MTM superstrate consisting of four-by-four MTM unit cell arrays, the second layer a patch antenna, and the third layer a rectifier circuit. By integrating the MTM superstrate on top of the patch antenna, the gain of the antenna is enhanced, owing to its beam focusing capability of the MTM superstrate. This induces the increase of the captured RF power at the rectifier input, resulting in high-output DC power and high entire end-to-end efficiency. A parametric analysis is performed in order to optimize the near-zero property of the MTM unit cell. In addition, the effects of the number of MTM unit cells on the performance of the integrated rectenna are studied. A prototype MTM-integrated rectenna, which is designed on an RO5880 substrate, is fabricated and characterized. The measured gain of the MTM-integrated rectenna is 11.87 dB. It shows a gain improvement of 6.12 dB compared to a counterpart patch antenna without an MTM superstrate and a maximum RF–DC conversion efficiency of 78.9% at an input RF power of 9 dBm. This results in the improvement of the RF–DC efficiency from 39.2% to 78.9% and the increase of the output DC power from 0.7 mW to 6.27 mW (a factor of 8.96 improvements). The demonstrated MTM-integrated rectenna has shown outstanding performance compared to other previously reported work. We emphasize that the demonstrated MTM-integrated rectenna has a low design complexity compared with other work, as the MTM superstrate layer is integrated on top of the simple patch antenna and rectifier circuit. In addition, the number of MTM units can be determined depending on applications. It is highly envisioned that the demonstrated MTM-integrated rectenna will provide new possibilities for practical energy harvesting applications with improved antenna gain and efficiency in various IoT environments.

This chapter tests the empirical validity of social learning, social bonding, and self-control theories as explanations of adolescent substance use in a sample of urban adolescents in South Korea. Ronald L. Akers has argued that there is considerable conceptual overlap between concept of definitions favorable and unfavorable in social learning theory and the concept of belief in social bonding theory. The chapter examines the relative explanatory power of independent variables from each of the theories when all are placed in the same regression models. It examines how well social learning, social bonding, and self-control theories, proposed and developed by Western sociologists but tested mainly with samples of American youth, explains adolescent substance use in non-Western Asian society. The chapter concludes that the theories do apply in Korean society and in about the same way that they apply in American society. It shows that social learning theory has been consistently and substantially supported by research and can be taken globally.

Solid phase crystallization (SPC) is carried out because of the best uniformity among the various crystallization methods. SPC poly-Si nonvolatile memory (NVM) is expected superior memory property in terms of stable reliability. This paper presents electrical properties of SPC poly-Si NVM on glass. Nonvolatile memory is an ideal portable storage device due to its characteristics of low-power consumption and compact size. Metal/oxide/nitride/oxide/silicon (MONOS) structure memory was fabricated on glass. Silicon oxynitride (SiO x N y ) layer grown by nitrous oxide plasma served as a carrier tunnel layer, silicon nitride (SiN x ) as charge trap region and silicon dioxide (SiO 2 ) for blocking oxide were deposited to fabricate NVM on SPC poly-Si. SiO x N y , SiN x , and SiO 2 films were deposited by using inductively coupled plasma chemical vapor deposition (ICP-CVD). Electrical properties of NVM on glass were analyzed gate voltage–drain current ( V G – I D ) and charge retention property. We obtained the NVM device with the programming voltage of − 12 V, erasing of 11 V, and fast programming/erasing (P/E) time of 1 ms. It has a threshold voltage window memory of about 3.7 V and it still keep a wide threshold voltage window of 2.3 V after 10 years.

In this work, the fabrication of nanostructures applicable to nano floating gate memory is investigated by using a block co-polymer system composed of Polystyrene (PS) and Polymethylmethacrylate (PMMA). A thin film of self-assembled block copolymer has been used during all experiments for nanostructures with critical dimensions below photolithographic resolution limits. Under suitable conditions, the PS and PMMA self assembled into a honey comb lattice of PMMA in the matrix of PS. Nanoporous thin film from PS-b-PMMA diblock co-polymer thin film with selective removal of PMMA domains was used to fabricate needle-like nanostructures. The reactive ion etching (RIE) was then carried out at room temperature in a single wafer RIE system with the substrate having nano-cylindrical structures. The plasma was excited by radio frequency. Diverse surface nanostructures of sub-100 nm patterning were fabricated by plasma etching using block co-polymer. Finally, we have demonstrated that by combining these self assembled block co-polymers with regular semiconductor processing, a non-volatile memory device with increased charge storage capacity over planar structures can be realized.

In this work, the silicon oxynitride layer was studied as a tunneling layer for non-volatile memory application by fabricating low temperature polysilicon thin film transistors on glass. Silicon wafers were oxynitrided by only nitrous oxide plasma under different radio frequency powers and plasma treatment times. Plasma oxynitridation was performed in RF plasma using inductively coupled plasma chemical vapor deposition. The X-ray energy dispersive spectroscopy was employed to analyze the atomic concentration ratio of nitrogen/oxygen in oxynitride layer. The oxynitrided layer formed under radio frequency power of 150 W and substrate temperature of 623 K was found to contain the atomic concentration ratio of nitrogen/oxygen as high as 1.57. The advantage of high nitrogen concentration in silicon oxide layer formed by using nitrous oxide plasma was investigated by capacitance–voltage measurement. The analysis of capacitance–voltage characteristics demonstrated that the ultra-thin oxynitride layers of 2 nm thickness formed by only nitrous oxide plasma have good properties as tunneling layer for non-volatile memory device.

Aluminium nitride (AlN) thin films were deposited by radio frequency (RF) magnetron sputtering on p-type silicon (Si) substrate of (1 0 0) orientation using only argon (Ar) gas at substrate temperature of 300 °C. In order to achieve improved electrical properties, we performed post-deposition rapid thermal annealing (RTA). Sputtered AlN films were annealed in an oxygen ambient at temperatures of 600, 700, and 800 °C using RTA for 30 min. The orientation of the AlN crystal in the film was investigated using X-ray diffraction (XRD). The characteristic spectra by functional group were analyzed by Fourier transformation infrared (FTIR) spectroscopy. The electrical properties of the AlN thin films were studied through capacitance–voltage ( C–V ) characteristics in metal–insulator–semiconductor (MIS) device using the films as insulating layers. The flatband voltages ( V FB ) in C–V curves were found to depend on crystal orientations. Negative V FB was found in the case when AlN (1 0 0) peak was found. Also, when AlN (1 0 3) peak was observed upon increasing the annealing temperature, the value of V FB was positive and after annealing at 700 °C, AlN (1 0 3) peak intensity was found to be maximum and V FB was as high as+6.5 V.

The analysis and findings reported here are from a self-report questionnaire survey of a sample of 1,035 high school students in Pusan, a metropolitan area of South Korea. Multiple regression and path analyses reveal that, for all types of drug behavior among these adolescents, the influence of parental variables was generally less than the influence of the peer variables. Even in South Korean society, where the stability and authority of the family is greater than in American society, peers have a greater influence than do parents on adolescents’ engaging in or refraining from deviant behavior. The findings conform more to the expectations of social learning theory than to those of social bonding theory, and generally replicate findings from research on adolescent drug use in the United States. Further research is clearly needed, but the findings here suggest that the social processes of substance use among adolescents and the theoretical explanations focusing on those processes are not confined to western societies.

In this work, metal–oxide–nitride–oxynitride–silicon (MONOS) devices with silicon oxynitride film as tunneling layer of nonvolatile memory have been fabricated. General chemical vapor deposition cannot generate uniform thickness of ultra-thin tunneling layer for fabrication of the nonvolatile memory device on glass because of rough poly-silicon surface due to melting/crystallization of substrate during irradiation of laser beam. plasma-assisted oxynitridation is applied to form uniform and ultra-thin tunneling layer instead of conventional deposition and nonvolatile memory devices were fabricated with oxide–nitride–oxynitride stack structure. The charge storage effect of MONOS devices with different oxide–nitride–oxynitride thickness was investigated by high frequency capacitance–voltage measurement. The results demonstrate that the MONOS device using oxide–nitride–oxynitride stack structure with a ultra-thin tunneling oxynitride of 2.3 nm thickness, a charge trapping layer of silicon nitride of 10 nm thickness, and a blocking layer of 8.5 nm thickness have the relative large ΔVFB of 9.13 V in the large range voltage sweeps ranging from the large range capacitance–voltage characteristic curves. The difference of flatband voltage between the programming and erasing states was initially 4.92 V and decreased to 3.22 V after 1000 s.

In this paper, we propose a blur identification for fully digital auto-focusing (FDAF) techniques under the assumption of isotropic point spread function (PSF). The proposed blur identification starts with the estimation of one-dimensional (1D) step response, and estimate the two-dimensional (2D) PSF using the fundamental relationship between the step and the impulse responses. For more accurate blur identification, we present the PSF interpolation method that fills out the PSF element off the concentric circle. We also propose least squares 2D PSF solutions that robustly estimates the strength of the concentric circles under noisy, incomplete observation environment. Experimental results prove that the proposed blur identification method outperforms the existing ones in the sense of both accuracy and efficiency.

This paper proposes a real-time digital auto-focusing algorithm using a priori estimated set of point spread functions (PSFs). A priori set of PSFs are estimated by establishing the relation between two-dimensional PSF and onedimensional step response whose elements are samples of profile of degraded step edge. From the priori estimated set, the proposed auto-focusing algorithm can select the optimal PSF by the focusing criterion based on the frequency domain analysis. We then use the constrained least square (CLS) filter to obtain the in-focused image with the estimated optimal PSF. The proposed algorithm can be implemented in real-time because the set of PSFs are already estimated and the filtering is performed in the frequency domain.

This paper proposes a fully digital auto-focusing algorithm for restoring the image with differently out-of-focused objects, which can restore background as well as all objects. In this paper, we assume that out-of-focus blur is isotropic such as circle of confusion (COC) or two-dimensional Gaussian blur. Therefore, the proposed algorithm can segment and estimate the point spread function (PSF) by using the size of ramp in the one-dimensional step response. The proposed algorithm can be developed by object-based image segmentation and restoration algorithm. Experimental results show that the proposed object-based image restoration algorithm can efficiently remove the space-variant out of focus blur from the image with multiple blurred objects.

This paper presents a digital auto-focusing algorithm based on evolutionary multiple object segmentation method. Robust object segmentation can be conducted by the evolutionary algorithm on an image that has several differently out-of-focused objects. After segmentation is completed, point spread functions (PSFs) are estimated at differently out-of-focused objects and spatially adaptive image restorations are applied according to the estimated PSFs. Experimental results show that the proposed auto-focusing algorithm can efficiently remove the space-variant out-of-focus blur from the image with multiple, blurred objects.

This paper explains how non-volatile memory (NVM) devices with an oxide/nitride/oxynitride (ONO) structure on a rough poly-silicon (poly-Si) surface were fabricated and studied using poly-Si thin film transistor (TFT) technology on a glass substrate. When a flat panel display (FPD) such as an organic light emitting diode (OLED) or a liquid crystal device (LCD) displays a static image, the brightness of the panel is altered because of degradation of the driving current. In order to prevent degradation of the driving current, an NVM device can be applied to the compensation circuit for the pixels of a FPD. To fabricate an NVM device on glass, a metal/oxide/nitride/oxynitride/poly-Si (MONOS) structure with an ultra-thin silicon oxynitride (SiOxNy) using nitrous oxide (N2O) plasma as the tunneling layer was used instead of the general methods of oxidation and deposition for ultra-thin silicon dioxide (SiO2). The memory window of a fabricated NVM device which has a MONOS structure with a tunneling layer of ult...

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A nonvolatile semiconductor memory (NVSM) device with a metal-oxide-nitride-oxynitride-polysilicon (MONOS) structure on a rough polysilicon (poly-Si) surface was fabricated using a low-temperature process and poly-Si thin film transistor (TFT) technology on glass. For the fabrication of the NVSM device on glass, plasma-assisted oxynitridation was carried out using nitrous oxide (N2O) as a reactive gas, due to the very rough surface of the poly-Si on glass annealed using an excimer laser. The ultrathin SiOxNy films obtained using the N2O plasma have a very uniform distribution on poly-Si and similar contents of oxygen and nitrogen in the peaks and valleys of the grains. The NVSM devices having a MONOS structure with a tunneling layer of ultrathin SiOxNy on glass have suitable switching and charge retention characteristics for data storage. The results demonstrate that the NVSM device made using low-temperature poly-Si TFT technology on glass reported in this paper can be used in various types of display de...