Computational analysis for morphological evolution in pyrolysis for micro/nano-fabrication

Pyrolysis is recently proposed as an efficient fabrication technique of micro/nanoscale carbon structures. In order to understand the morphological evolution in pyrolysis and design the final shape of carbon structure, this study proposes a comprehensive model that incorporates the essential mechanisms of pyrolysis based on the phase field framework. Computational analysis with the developed model provides information about the effect of interface energy and kinetic rate on the morphological evolution in pyrolysis.open0

Robot-Assisted Radical Prostatectomy:Modified Ultradissection Reduces pT2 Positive Surgical Margins on the Bladder Neck

The purpose of this study was to compare the positive surgical margin (PSM) rates of 2 techniques of robot-assisted radical prostatectomy (RARP) for pT2 (localized) prostate cancer. A retrospective analysis was conducted of 361 RARP cases, performed from May 2005 to September 2008 by a single surgeon (KHR) at our institution (Yonsei University College of Medicine). In the conventional technique, the bladder neck was transected first. In the modified ultradissection, the lateral border of the bladder neck was dissected and then the bladder neck was transected while the detrusor muscle of the bladder was well visualized. Perioperative characteristics and outcomes and PSM rates were analyzed retrospectively for pT2 patients (n＝217), focusing on a comparison of those undergoing conventional (n＝113) and modified ultradissection (n＝104) techniques. There was no difference between the conventional and modified ultradissection group in mean age, BMI, PSA, prostate volume, biopsy Gleason score, and DʼAmico prognostic criteria distributions. The mean operative time was shorter (p＜0.001) and the estimated blood loss was less (p＜0.01) in the modified ultradissection group. The PSM rate for the bladder neck was significantly reduced by modified ultradissection, from 6.2% to 0% (p＜0.05). In conclusion, modified ultradissection reduces the PSM rate for the bladder neck

Pharmacologic Activation of Angiotensin-Converting Enzyme II Alleviates Diabetic Cardiomyopathy in db/db Mice by Reducing Reactive Oxidative Stress

Background Diabetes mellitus is one of the most common chronic diseases worldwide, and cardiovascular disease is the leading cause of morbidity and mortality in diabetic patients. Diabetic cardiomyopathy (DCM) is a phenomenon characterized by a deterioration in cardiac function and structure, independent of vascular complications. Among many possible causes, the renin-angiotensin-aldosterone system and angiotensin II have been proposed as major drivers of DCM development. In the current study, we aimed to investigate the effects of pharmacological activation of angiotensin-converting enzyme 2 (ACE2) on DCM. Methods The ACE2 activator diminazene aceturate (DIZE) was administered intraperitoneally to male db/db mice (8 weeks old) for 8 weeks. Transthoracic echocardiography was used to assess cardiac mass and function in mice. Cardiac structure and fibrotic changes were examined using histology and immunohistochemistry. Gene and protein expression levels were examined using quantitative reverse transcription polymerase chain reaction and Western blotting, respectively. Additionally, RNA sequencing was performed to investigate the underlying mechanisms of the effects of DIZE and identify novel potential therapeutic targets for DCM. Results Echocardiography revealed that in DCM, the administration of DIZE significantly improved cardiac function as well as reduced cardiac hypertrophy and fibrosis. Transcriptome analysis revealed that DIZE treatment suppresses oxidative stress and several pathways related to cardiac hypertrophy. Conclusion DIZE prevented the diabetes mellitus-mediated structural and functional deterioration of mouse hearts. Our findings suggest that the pharmacological activation of ACE2 could be a novel treatment strategy for DCM

Yonsei Experience in Robotic Urologic Surgery - Application in Various Urological Procedures

PURPOSE: The da Vinci robot system has been used to perform complex reconstructive procedures in a minimally invasive fashion. Robot-assisted laparoscopic radical prostatectomy has recently established as one of the standard cares. Based on experience with the robotic prostatectomy, its use is naturally expanding into other urologic surgeries. We examine our practical pattern and application of da Vinci robot system in urologic field. PATIENTS AND METHODS: Robotic urologic surgery has been performed during a period from July 2005 to August 2008 in a total of 708 cases. Surgery was performed by 7 operators. In our series, radical prostatectomy was performed in 623 cases, partial nephrectomy in 43 cases, radical cystectomy in 11 cases, nephroureterectomy in 18 cases and other surgeries in 15 cases. RESULTS: In the first year, robotic urologic surgery was performed in 43 cases. However, in the second year, it was performed in 164 cases, and it was performed in 407 cases in the third year. In the first year, only prostatectomy was performed. In the second year, partial nephrectomy (2 cases), nephroureterectomy (3 cases) and cystectomy (1 case) were performed. In the third year, other urologic surgeries than prostatectomy were performed in 64 cases. The first robotic surgery was performed with long operative time. For instance, the operative time of prostatectomy, partial nephrectomy, cystectomy and nephroureterectomy was 418, 222, 340 and 320 minutes, respectively. Overall, the mean operative time of prostatectomy, partial nephrectomy, cystectomy and nephrourectectomy was 179, 173, 309, and 206 minutes, respectively. CONCLUSION: Based on our experience at a single-institution, robot system can be used both safely and efficiently in many areas of urologic surgeries including prostatectomy. Once this system is familiar to surgeons, it will be used in a wide range of urologic surgeryope

Adaptive Coding and Modulation Scheme for Ka Band Space Communications

Rain attenuation can cause a serious problem that an availability of space communication link on Ka band becomes low. To reduce the effect of rain attenuation on the error performance of space communications in Ka band, an adaptive coding and modulation (ACM) scheme is required. In this paper, to achieve a reliable telemetry data transmission, we propose an adaptive coding and modulation level using turbo code recommended by the consultative committee for space data systems (CCSDS) and various modulation methods (QPSK, 8PSK, 4+12 APSK, and 4+12+16 APSK) adopted in the digital video broadcasting-satellite2 (DVB-S2)

Penetration of Hydrogen into Polymer Electrolyte Membrane for Fuel Cells by Quantum and Molecular Dynamics Simulations

The advent of the Hydrogen Society created great interest around hydrogen-based energy a decade ago, with several types of vehicles based on hydrogen fuel cells already being produced in the automotive sector. For highly efficient fuel cell systems, the control of hydrogen inside a polymer-based electrolyte membrane is crucial. In this study, we investigated the molecular behavior of hydrogen inside a polymer-based proton-exchange membrane, using quantum and molecular dynamics simulations. In particular, this study focused on the structural difference of the pendent-like side chain polymer, resulting in the penetration ratio of hydrogen into the membrane deriving from the penetration depth of the membrane’s thickness while keeping the simulation time constant. The results reveal that the penetration ratio of the polymer with a shorter side chain was higher than that with the longer side chain. This was justified via two perspectives; electrostatic and van der Waals molecular interactions, and the structural difference of the polymers resulting in the free volume and different behavior of the side chain. In conclusion, we found that a longer side chain is more trembling and acts as an obstruction, dominating the penetration of hydrogen inside the polymer membrane

A CNN-Based High-Accuracy Registration for Remote Sensing Images

In this paper, a convolutional neural network-based registration framework is proposed for remote sensing to improve the registration accuracy between two remote-sensed images acquired from different times and viewpoints. The proposed framework consists of four stages. In the first stage, key-points are extracted from two input images—a reference and a sensed image. Then, a patch is constructed at each key-point. The second stage consists of three processes for patch matching—candidate patch pair list generation, one-to-one matched label selection, and geometric distortion compensation. One-to-one matched patch pairs between two images are found, and the exact matching is found by compensating for geometric distortions in the matched patch pairs. A global geometric affine parameter set is computed using the random sample consensus algorithm (RANSAC) algorithm in the third stage. Finally, a registered image is generated after warping the input sensed image using the affine parameter set. The proposed high-accuracy registration framework is evaluated using the KOMPSAT-3 dataset by comparing the conventional frameworks based on machine learning and deep-learning-based frameworks. The proposed framework obtains the least root mean square error value of 34.922 based on all control points and achieves a 68.4% increase in the matching accuracy compared with the conventional registration framework

The Importance of Social Value in the Evaluation of Web Services in the Public Sector

Wireless sensor networks (WSNs) are widely used in many different fields. Even in the public sector, various services using WSN are offered. One of the key issues is how to control and manage heterogeneous devices of WSN devices. Devices Profile for Web Services (DPWS), a standard of Web services, has been adopted to solve the problems of interoperability between WSN devices. In order to evaluate WSN services in the public sector, this paper presents a method to evaluate Web services, a base technology of sensor network services. This paper presents a value analysis methodology assessing tangible and intangible benefits of Web services in the public sector. We classify stakeholders of Web services as a government, citizens, and agents (businesses) and selected the metrics for each stakeholder's benefit. After that, we determine the weight of each metric through AHP. The result shows that social value was the most important benefit in the construction of Web services in the public sector. We expect that the main contribution of this paper is the development of a value assessment framework that reflects the unique characteristics of Web services in the public sector

Design and Performance Analysis of Downlink in Space Communications System for Lunar Exploration

This paper designs a data link between a Lunar Orbiter (LO) and an Earth Station (ES), and analyzes the downlink performance of a space communications system for lunar exploration, conforming to the recommendations by the Consultative Committee for Space Data Systems (CCSDS). The results provided in the paper can be useful references for the design of reliable communication link for the Korean lunar exploration in the near future

Bilateral Attention U-Net with Dissimilarity Attention Gate for Change Detection on Remote Sensing Imageries

This study proposes a bilateral attention U-Net with a dissimilarity attention gate (DAG) for change detection on remote sensing imageries. The proposed network is designed with a bilateral dissimilarity encoding for the DAG calculation to handle reversible input images, resulting in high detection rates regardless of the order of the two input images for change detection. The DAG exploits all the combinations of joint features to avoid spectral information loss fed into an attention gate on the decoder side. The effectiveness of the proposed method was evaluated on the KOMPSAT-3 satellite images dataset and the aerial change detection dataset (CDD). Its performance was better than that of conventional methods (specifically, U-Net, ATTUNet, and Modified-UNet++) as it achieved average F1-score and kappa coefficient (KC) values of 0.68 and 66.93, respectively, for the KOMPSAT-3 dataset. For CDD, it achieved F1-score and KC values of 0.70 and 68.74, respectively, which are also better values than those achieved by conventional methods. In addition, we found that the proposed bilateral attention U-Net can provide the same changed map regardless of whether the image order is reversed