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This paper presents 2G/3G/4G/5G transmitter that has a compact die area and supports multi bands in 5G new radio (NR). The transmitter with inter-digitated switchable transformer is designed to support n77/n78/n79 of 5G FR1 bands (3.2GHz to 5GHz) and B46/B47 of V2X bands (5.125GHz to 5.925GHz). The transformer provides optimum transformed load impedance at the drive amplifier output with 3-stacked switches. The on-chip transformer with inter-digitated structure results in a high coupling factor to minimize the insertion loss. An interstage matching network between a mixer and a drive amplifier induces a channel flatness characteristic. The designed transmitter is fabricated using a 14nm FinFET CMOS process. It achieves a peak average output power of 7dBm and 2% under measured root mean square (rms) EVM in the case of DFT-s-OFDM 256QAM Full-RB signal, while satisfying the 3GPP specification. It also satisfies 1dB under channel flatness and the adjacent channel leakage ratio (ACLR) −43.2dBc in case of n77/n78, and −42.7dBc in case of n79, while consuming 295mW and 300mW dc power at 7.5dBm and 6.7dBm output power, respectively. The transmitter with inter-digitated switchable transformer has a size of 0.18mm2.

Deploying deep convolutional neural networks on ultra-low power systems is challenging due to the extremely limited resources. Especially, the memory becomes a bottleneck as the systems put a hard limit on the size of on-chip memory. Because peak memory explosion in the lower layers is critical even in tiny models, the size of an input image should be reduced with sacrifice in accuracy. To overcome this drawback, we propose a novel Raster-Scanning Network, named RaScaNet, inspired by raster-scanning in image sensors. RaScaNet reads only a few rows of pixels at a time using a convolutional neural network and then sequentially learns the representation of the whole image using a recurrent neural network. The proposed method operates on an ultra-low power system without input size reduction; it requires 15.9–24.3× smaller peak memory and 5.3–12.9× smaller weight memory than the state-of-the-art tiny models. Moreover, RaScaNet fully exploits on-chip SRAM and cache memory of the system as the sum of the peak memory and the weight memory does not exceed 60 KB, improving the power efficiency of the system. In our experiments, we demonstrate the binary classification performance of RaScaNet on Visual Wake Words and Pascal VOC datasets.

Introduction Textbook outcome is a composite quality measurement of short-term outcomes for evaluating complex surgical procedures. We compared textbook outcome and survival of robotic total gastrectomy(RTG) with those of laparoscopic total gastrectomy(LTG).Methods We retrospectively reviewed 395patients(RTG,n = 74;LTG,n = 321) who underwent curative total gastrectomy for gastric cancer via minimally invasive approaches from 2009 to 2018. We performed propensity score matched analysis to adjust for potential selection bias. Textbook outcome included a negative resection margin, no intraoperative complication, retrieved lymph nodes > 15, no severe complication, no reintervention, no unplanned intensive care unit admission, hospitalisation ≤ 21days, no readmission after discharge, and no postoperative mortality. Survival outcomes included 5-year overall and relapse-free survival rates.Results After matching, 74patients in each group were selected. Textbook outcome was similar in the RTG and LTG groups(70.3% and 75.7%,respectively), although RTG required a longer operative time. The quality metric least often achieved was the presence of severe complications in both groups(77.0% in both groups). There were no differences in the 5-year overall survival rate(90.7% and 85.9%,respectively;log-rank P = 0.144) and relapse-free survival rate between the RTG and LTG groups(89.5% and 85.2%,respectively;log-rank P = 0.167).Conclusion Textbook outcome and survival outcome of RTG were comparable to those of LTG for gastric cancer.

A novel manufacturing process for expanding the tubes of fin-tube type heat exchangers using a three-dimensional (3D) spiral expanding ball fabricated via metal additive manufacturing was proposed for the manufacture of highly efficient heat exchangers. To improve the heat transfer efficiency of fin-tube type heat exchangers, fine grooves are generally formed inside a tube to increase the heat transfer area. However, the height of a groove is commonly reduced when a tube is expanded for tightening with fins. To address this issue, a 3D expanding ball with spiral grooves was first developed and used in the expansion process. In conventional tube expansion, the height reduction of grooves is approximately 10.3 %. However, we demonstrated that it was dramatically improved, reaching approximately 1.7 %, when the proposed process with a 3D expanding ball was applied. We believe that this approach can be used in practical industries to manufacture highly efficient fin-tube heat exchangers.

Carbon electrode-based perovskite solar cells (PSCs) with low-cost and long-term stability have been recognized as a competitive candidate toward future practical applications. However, energy leve...

Linear-shaped gastroduodenostomy (LSGD) is a new method of intracorporeal reconstruction that is simpler to perform and associated with a lower rate of bile reflux than delta-shaped anastomosis. Here, we analyzed the learning curve of LSGD in totally laparoscopic distal gastrectomy. The cumulative sum method was used to retrospectively analyze consecutive gastric cancer patients undergoing intracorporeal gastroduodenostomy after distal gastrectomy between January 2009 and May 2016. The duration of surgery, postoperative complications, hospital stay, and endoscopic findings in the postoperative period and the first, third, and fifth year were evaluated according to the two phases of the learning curve (learning period versus mastery period). Data from 222 patients were included in the analysis. The LSGD learning period was 29 cases. The surgical time in mastery period was significantly shorter than the learning period (124.9 ± 34.5 versus 168.2 ± 42.0 min, p

Purpose Intraoperative peritoneal washing cytology (PWC) is used to determine treatment strategies for gastric cancer with suspected serosal invasion. However, a standard staining method for intraoperative PWC remains to be established. We evaluated the feasibility of a rapid and simple staining method using Shorr's stain for intraoperative PWC in advanced gastric cancer. Materials and methods Between November 2012 and December 2014, 77 patients with clinical T3 or higher gastric cancer were enrolled. The sensitivity, specificity, and concordance between the Shorr staining method and conventional Papanicolaou (Pap) staining with carcinoembryonic antigen (CEA) immunohistochemistry (IHC) were analyzed. Results Intraoperative PWC was performed laparoscopically in 69 patients (89.6%). The average time of the procedure was 8.3 minutes, and the average amount of aspirated fluids was 83.3 mL. The average time for Shorr staining and pathologic review was 21.0 minutes. Of the 77 patients, 16 (20.7%) had positive cytology and 7 (9.1%) showed atypical findings; sensitivity and specificity were 73.6% and 98.2% for the Shorr method, and 78.9% and 98.2% for the Pap method with CEA IHC, respectively. Concordance of diagnosis between the 2 methods was observed in 90.9% of cases (weighted κ statistic=0.875) and most disagreements in diagnoses occurred in atypical findings (6/7). In overall survival, there was no significant difference in C-index between the 2 methods (0.459 in Shorr method vs. 0.458 in Pap with CEA IHC method, P=0.987). Conclusions Shorr staining could be a rapid and reliable method for intraoperative PWC in advanced gastric cancer.

Three-dimensional (3D) printing, with its capability for producing arbitrary shapes, has been extensively studied for tissue engineering applications. However, clinical applications, especially for soft tissues, have been limited due to mechanical mismatch between the 3D-printed artificial tissues and the native tissues. Here, we suggest an integrative method of 3D printing, dip coating, and salt leaching for the fabrication of soft 3D freeform porous tubes, which are expected to be applied to the engineering of vascular tissues. Owing to their porous morphology and controlled wall thickness, the processed tubular constructs had flexible properties comparable to those of native soft tissues with a modulus range of several MPa. When thermoplastic polyurethane (TPU) was used as the dip-coating material, the porous tube exhibited a low tensile modulus from 1.47 to 2.47 MPa and a high elongation limit of over 400%. These flexible properties, which were clearly differentiated from the stiffness of 3D-printed samples with moduli of tens or hundreds of MPa, were confirmed to mimic the mechanical properties of native tissues. Furthermore, by varying the material composition in the dip-coating process, the flexibility of the tube could be modulated when stiffer polycaprolactone (PCL) layers were combined. In addition, such a combination using biocompatible materials could be expected to provide safer interaction at surgical interfaces. Synergistically with the mechanical flexibility, since the proposed method was based on a 3D-printed template, the resulting construct would have extensive applicability in patient-specific tissue engineering.

The development of scalable deposition methods for stable perovskite layers is a prerequisite for the development and future commercialization of perovskite solar modules. However, there are two major challenges, i.e., scalability and stability. In sharp contrast to a previous report, here we develop a fully vapor based scalable hybrid chemical vapor deposition (HCVD) process for depositing Cs-formamidinium (FA) mixed cation perovskite films, which alleviates the problem encountered when using conventional solution coating of mainly methylammonium lead iodide (MAPbI3). Using our HCVD method, we fabricate perovskite films of Cs0.1FA0.9PbI2.9Br0.1 with enhanced thermal and phase stabilities, by the intimate incorporation of Cs into FA based perovskite films. In addition, the SnO2 electron transport layer (ETL) (prepared by sputter deposition) is found to be damaged during the HCVD process. In combination with precise interface engineering of the SnO2 ETL, we demonstrate relatively large area solar modules with efficiency approaching 10% and with a designated area of 91.8 cm2 fabricated on 10 cm × 10 cm substrates (14 cells in series). On the basis of our preliminary operational stability tests on encapsulated perovskite solar modules, we extrapolated that the T80 lifetime is approximately 500 h (under the light illumination of 1 sun and 25 °C).

The dissemination of distributed resources presents a new paradigm for the power industry. Especially solar power is creating a new chapter for trading electricity as a new source. Solar power sources and load resources are each uncertain by their size and time factors. This paper discusses the uncertainties due to the accuracy of the forecast by forecasting PV power source and by forecasting load resource based multi-scale and multi-time. To do this, artificial neural networks are used to forecast these resources at a different time interval and the amounts by aggregation. Uncertainty from the forecasting results is discussed.

Lithium-ion batteries (LIBs) continue to draw vast attention as a promising energy storage technology due to their high energy density, low self-discharge property, nearly zero-memory effect, high open circuit voltage, and long lifespan. In particular, high-energy density lithium-ion batteries are considered as the ideal power source for electric vehicles (EVs) and hybrid electric vehicles (HEVs) in the automotive industry, in recent years. This review discusses key aspects of the present and the future battery technologies on the basis of the working electrode. We then discuss how lithium-ion batteries evolve to meet the growing demand on high charge capacity and electrode stability. An account of a stand-alone energy device (off-grid system) that combines an energy harvesting technology with a lithium-ion battery is also provided. The main discussion is categorized into three perspectives such as the evolution from the conventional to the advanced LIBs (e.g., Li-rich transition metal oxide and Ni-rich transition metal oxide batteries), to the state-of-the-art LIBs (e.g., Li–air, Li–sulfur batteries, organic electrode batteries, solid-state batteries, and Li–CO2 batteries), and to the hybridized LIBs (e.g., metal halide perovskite batteries).

Energy consumers are evolving into energy prosumers that simultaneously perform the role of production and consumption. The activation of energy transaction owing to the increase of energy prosumers affects the stability management of distribution system. Accordingly, the role of the distribution system operator (DSO) for managing the power distribution system is becoming important. In a power distribution system with low demand, if a prosumers trade large amounts of power through peer-to-peer energy transaction (P2P-ET), an overvoltage problem may occur. In this study, a distribution system voltage management method through interaction between DSO and local energy transaction community (LETC) which performs P2P-ET is proposed. The effect of the proposed model is validated through a case study considering the LETC that local prosumers pool-based P2P-ET is performed.

Potholes, a kind of road defect, can damage vehicles and negatively affect drivers’ safe driving, and in severe cases can lead to traffic accidents. Efficient and preventive management of potholes in a complex road environment plays an important role in securing driver safety. It is also expected to contribute to the prevention of traffic accidents and the smooth flow of traffic. In the past, pothole detection was mainly performed via visual inspection by human experts. Recently, automated pothole-detection methods apply various technologies that converge basic technologies such as sensors and signal processing. The automated pothole-detection methods can be classified into three types according to the technology used in the pothole-recognition process: a vision-based method, a vibration-based method, and a 3D reconstruction-based method. In this paper, three methods are compared, and the strengths and weaknesses of each method are summarized. The detection process and technology proposed in the latest research related to automated pothole detection are described for each method. The development plans of future technology that is connected with those studies are also presented in this paper.

Few current preoperative risk assessment tools provide essential, optimized treatment for gastric cancer. The purpose of this study was to develop and validate a nomogram that uses preoperative data to predict survival and risk assessments. A survival prediction model was constructed using data from a developmental cohort of 1251 patients with stage I to III gastric cancer who underwent curative resection between January 2005 and December 2008 at Ajou University Hospital, Korea. The model was internally validated for discrimination and calibrated using bootstrap resampling. To externally validate the model, data from a validation cohort of 2012 patients with stage I to III gastric cancer who underwent surgery at multiple centers in Korea between January 2001 and June 2006 were analyzed. Analyses included the model’s discrimination index (C-index), calibration plots, and decision curve that predict overall survival. Eight independent predictors, including age, sex, clinical tumor size, macroscopic features, body mass index, histology, clinical stages, and tumor location, were considered for developing the nomogram. The discrimination index was 0.816 (adjusted C-index) in the developmental cohort and 0.781 (adjusted C-index) in the external validation cohort. Additionally, in both the developmental and validation datasets, age and tumor size were significantly correlated with each other and were independent indicators for survival (P < 0.05). We developed a new nomogram by using the most common and significant preoperative parameters that can help to identify high-risk patients before treatment and help clinicians to make appropriate decisions for patients with stage I to III gastric cancer.

Activity of daily living (ADL) is a criterion for evaluating the performance ability of daily life by recognizing various activity events occurring in real life. However, most of the data necessary for ADL evaluation are collected only through observation and questionnaire by the patient or the patient&rsquo, s caregiver. Recently, Internet of Things (IoT) device studies using various environmental sensors are being used for ADL collection and analysis. In this paper, we propose an IoT Device Platform for ADL capability measurement. Wearable devices and stationary devices recognize activity events in real environments and perform user identification through various sensors. The user&rsquo, s ADL data are sent to the network hub for analysis. The proposed IoT platform devices support many sensor devices such as acceleration, flame, temperature, and humidity in order to recognize various activities in real life. In addition, in this paper, using the implemented platform, ADL measurement test was performed on hospital patients. Through this test, the accuracy and reliability of the platform are analyzed.

To investigate the quality of life (QOL) of patients after laparoscopic sentinel node navigation surgery (SNNS) compared to conventional laparoscopy-assisted distal gastrectomy (LADG) in early gastric cancer patients. Patients recruited for laparoscopic SNNS surgery between July 2010 and April 2013 were assessed for their QOL. A historical control group was established, consisting of patients who underwent conventional LADG with radical lymphadenectomy from the same institution. QOL questionnaire was taken serially from preoperative week 1 until 12 months postoperatively (1, 3, 6, and 12 months) using the Korean version of the European Organization for Research and Treatment of Cancer (EORTC) QOL questionnaire-core (QLQ-C30) and gastric cancer-specific questionnaire (STO22). A total of 80 prospectively gathered patients who received SNNS were categorized into the comparison group (SNNS group). The QOL was compared with 78 patients identified to have received LADG from the gastric cancer database of our institution and were sorted into the control group (LADG group). In QLQ-C30, SNNS group showed better functioning scales in all except role functioning and better scores from the symptom scales in fatigue, insomnia, and diarrhea compared to the LADG group. In QLQ-STO22, scores on dysphagia, eating restriction, anxiety, and body image disturbance were better in SNNS group. Postoperative QOL in laparoscopic gastrectomy combined with SNNS is superior compared to conventional laparoscopic distal gastrectomy in patients with stage I gastric cancer.

To tune the electronic and optoelectronic properties of graphene quantum dots (GQDs), heteroatom doping (e.g., nitrogen (N), boron (B), and sulfur (S)) is an effective method. However, it is difficult to incorporate S into the carbon framework of GQDs because the atomic size of S is much larger than that of C atoms, compared to N and B. In this study, we report a simple and one-step method for the synthesis of sulfur-doped GQDs (S-GQDs) via the pulsed laser ablation in liquid (PLAL) process. The as-prepared S-GQDs exhibited enhanced fluorescence quantum yields (0.8% → 3.89%) with a huge improved absorption band in ultraviolet (UV) region (200 ∼ 400 nm) and excellent photo stability under the UV radiation at 360 nm. In addition, XPS results revealed that the PLAL process can effectively facilitate the incorporation of S into the carbon framework compared to those produced by the chemical exfoliation method (e.g., hydrothermal method). And also, the mechanisms related with the optical properties of S-GQDs was investigated by time-resolved photoluminescence (TRPL) spectroscopy. We believe that the PLAL process proposed in this study will serve as a simple and one-step route for designing S-GQDs and opens up to opportunities for their potential applications.

Peritoneal recurrence of gastric cancer after curative surgical resection is common and portends a poor prognosis. Early studies suggest that extensive intraoperative peritoneal lavage (EIPL) might reduce the risk of peritoneal recurrence and improve survival. We aimed to evaluate the survival benefit of EIPL in patients with gastric cancer undergoing curative gastrectomy.In this open-label, phase 3, multicentre randomised trial, patients aged 21-80 years with cT3 or cT4 gastric cancer undergoing curative resection were enrolled at 22 centres from South Korea, China, Japan, Malaysia, Hong Kong, and Singapore. Patients were randomly assigned to receive surgery and EIPL (EIPL group) or surgery alone (standard surgery group) via a web-based programme in random permuted blocks in varying block sizes of four and six, assuming equal allocation between treatment groups. Randomisation was stratified according to study site and the sequence was generated using a computer program and concealed until the interventions were assigned. After surgery in the EIPL group, peritoneal lavage was done with 1 L of warm (42°C) normal 0·9% saline followed by complete aspiration; this procedure was repeated ten times. The primary endpoint was overall survival. All analyses were done assuming intention to treat. This trial is registered with ClinicalTrials.gov, NCT02140034.Between Sept 16, 2012, and Aug 3, 2018, 800 patients were randomly assigned to the EIPL group (n=398) or the standard surgery group (n=402). Two patients in the EIPL group and one in the standard surgery group withdrew from the trial immediately after randomisation and were excluded from the intention-to-treat analysis. At the third interim analysis on Aug 28, 2019, the predictive probability of overall survival being significantly higher in the EIPL group was less than 0·5%; therefore, the trial was terminated on the basis of futility. With a median follow-up of 2·4 years (IQR 1·5-3·0), the two groups were similar in terms of overall survival (hazard ratio 1·09 [95% CI 0·78-1·52; p=0·62). 3-year overall survival was 77·0% (95% CI 71·4-81·6) for the EIPL group and 76·7% (71·0-81·5) for the standard surgery group. 60 adverse events were reported in the EIPL group and 41 were reported in the standard surgery group. The most common adverse events included anastomotic leak (ten [3%] of 346 patients in the EIPL group vs six [2%] of 362 patients in the standard surgery group), bleeding (six [2%] vs six [2%]), intra-abdominal abscess (four [1%] vs five [1%]), superficial wound infection (seven [2%] vs one [1%]), and abnormal liver function (six [2%] vs one [1%]). Ten of the reported adverse events (eight in the EIPL group and two in the standard surgery group) resulted in death.EIPL and surgery did not have a survival benefit compared with surgery alone and is not recommended for patients undergoing curative gastrectomy for gastric cancer.National Medical Research Council, Singapore.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

There have recently been an increasing number of variable renewable energy curtailment cases to manage power system stability problems caused by the overproduction of variable renewable energy. Variable renewable energy curtailment can be a factor that hinders the development of the power industry by reducing the economic viability of variable renewable energy operators and the efficiency of energy use. In this study, an economic curtailment methodology using electric vehicles to mitigate energy waste and economic losses is proposed. Charging point operators participate in incentive-based demand response programs with their charging station loads under curtailment situations. A location-based incentive algorithm considering distribution system constraints is proposed to avoid distribution system congestion. A response model based on random arrival electric vehicles considering demand and price elasticity, time pressure, and charging pressure is developed. The proposed methodology is verified through case studies based on the environment of Jeju Island in Korea. The case study results show that the proposed methodology can use energy more economically and effectively than conventional variable renewable energy curtailment methodology.