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Design of Cold-Junction Compensation and Disconnection Detection Circuits of Various Thermocouples and Implementation of Multi-Channel Interfaces Using Them-A Secondary Publication
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作者 Hyeong-Woo Cha 《Journal of Electronic Research and Application》 2024年第1期93-105,共13页
Cold-junction compensation(CJC)and disconnection detection circuit design of various thermocouples(TC)and multi-channel TC interface circuits were designed.The CJC and disconnection detection circuit consists of a CJC... Cold-junction compensation(CJC)and disconnection detection circuit design of various thermocouples(TC)and multi-channel TC interface circuits were designed.The CJC and disconnection detection circuit consists of a CJC semiconductor device,an instrumentation amplifier(IA),two resistors,and a diode for disconnection detection.Based on the basic circuit,a multi-channel interface circuit was also implemented.The CJC was implemented using compensation semiconductor and IA,and disconnection detection was detected by using two resistors and a diode so that IA input voltage became-0.42 V.As a result of the experiment using R-type TC,the error of the designed circuit was reduced from 0.14 mV to 3μV after CJC in the temperature range of 0°C to 1400°C.In addition,it was confirmed that the output voltage of IA was saturated from 88 mV to-14.2 V when TC was disconnected from normal.The output voltage of the designed circuit was 0 V to 10 V in the temperature range of 0°C to 1400°C.The results of the 4-channel interface experiment using R-type TC were almost identical to the CJC and disconnection detection results for each channel.The implemented multi-channel interface has a feature that can be applied equally to E,J,K,T,R,and S-type TCs by changing the terminals of CJC semiconductor devices and adjusting the IA gain. 展开更多
关键词 R-type thermocouple(TC) Cold-junction compensation(CJC) TC disconnection detection Multi-channel interface circuit Sensor interface
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A New Simulation Model for Recoil Analysis of Deep-Water Drilling Risers After Emergency Disconnection 被引量:1
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作者 WU Jun-kang MENG Shuai 《China Ocean Engineering》 SCIE EI CSCD 2023年第4期637-644,共8页
The recoil response of a deep-water drilling riser following an ED(Emergency Disconnection)scenario is a transient and sensitive process.The recoiling displacement of the riser is the resultant of recoil motion and ax... The recoil response of a deep-water drilling riser following an ED(Emergency Disconnection)scenario is a transient and sensitive process.The recoiling displacement of the riser is the resultant of recoil motion and axial stretch.How-ever,it is typically represented by one variable in recoil simulations.As axial deformation is quite small compared with axial motion in the recoil process,it inevitably introduces numerical errors(i.e.,a large number annihilating a small number).Thus,it is hard to perform a quantitative analysis of axial deformation,although a consensus initial deformation is essential for recoil dynamics.Moreover,the triggered axial natural modes have never been examined before.In this study,the recoil response is decomposed into two parts:recoil motion and axial deformation,and a novel model is developed by Galerkin method.It has demonstrated that the initial stretch has a significant effect at the initial stage in recoil.The existing models underestimate the effects of axial deformation.The new model can capture information of triggered natural modes and figure out the modes undergoing dynamic compression.This study can be beneficial to overpull setting,determination of ED time and anti-recoil control optimization. 展开更多
关键词 recoil analysis drilling riser emergency disconnection axial deformation Galerkin method
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Gastroduodenal artery disconnection during liver transplantation decreases non-anastomotic stricture incidence 被引量:1
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作者 Bi Pan Wei Liu +6 位作者 Yan-Jiao Ou Yan-Qi Zhang Di Jiang Yuan-Cheng Li Zhi-Yu Chen Lei-Da Zhang Cheng-Cheng Zhang 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2023年第1期28-33,共6页
Background:The hepatic artery is the only blood source nourishing the biliary duct and associated with biliary complication after liver transplantation(LT).Gastroduodenal artery(GDA)disconnection increased proper hepa... Background:The hepatic artery is the only blood source nourishing the biliary duct and associated with biliary complication after liver transplantation(LT).Gastroduodenal artery(GDA)disconnection increased proper hepatic artery flow.Whether this procedure attenuates biliary non-anastomotic stricture(NAS)is not clear.Methods:A total of 241 patients with LT were retrospectively analyzed.The patients were divided into the GDA disconnection(GDA-)and GDA preservation(GDA+)groups.Propensity score matching(PSM)was administrated to reduce bias.Logistic regression was conducted to analyze risk factors for biliary NAS before and after PSM.Postoperative complications were compared.Kaplan-Meier survival analysis and log-rank tests were performed to compare overall survival.Results:In all,99 patients(41.1%)underwent GDA disconnection,and 49(20.3%)developed NAS.Multivariate logistic regression revealed that GDA preservation(OR=2.24,95%CI:1.11-4.53;P=0.025)and model for end-stage liver disease(MELD)score>15(OR=2.14,95%CI:1.12-4.11;P=0.022)were risk factors for biliary NAS.PSM provided 66 pairs using 1:2 matching method,including 66 GDA disconnection and 99 GDA preservation patients.Multivariate logistic regression after PSM also showed that GDA preservation(OR=3.15,95%CI:1.26-7.89;P=0.014)and MELD score>15(OR=2.41,95%CI:1.08-5.36;P=0.031)were risk factors for NAS.When comparing complications between the two groups,GDA preservation was associated with a higher incidence of biliary NAS before and after PSM(P=0.031 and 0.017,respectively).In contrast,other complications including early allograft dysfunction(P=0.620),small-for-size graft syndrome(P=0.441),abdominal hemorrhage(P=1.000),major complications(Clavien-Dindo grade≥3,P=0.318),and overall survival(P=0.088)were not significantly different between the two groups.Conclusions:GDA disconnection during LT ameliorates biliary NAS incidence and may be recommended for application in clinical practice. 展开更多
关键词 Liver transplantation Biliary complication Gastroduodenal artery disconnection Hepatic artery hyperperfusion
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Morphogenesis of Floating Bone Segments: A Legacy of Serial Tensile Cross-Strut Microdamage in Trabecular Disconnection “Crumple Zones”?
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作者 Patricia A. Shore Roger C. Shore Jean E. Aaron 《Journal of Biomedical Science and Engineering》 2023年第5期65-79,共15页
Trabecular bone disconnection “hotspots” of real termini (ReTm) previously mapped as loci of weakness in the female aging spine and hip may be a source of free-floating cancellous segments found in the medullary spa... Trabecular bone disconnection “hotspots” of real termini (ReTm) previously mapped as loci of weakness in the female aging spine and hip may be a source of free-floating cancellous segments found in the medullary space using a bespoke, thick slice histological method for identifying ReTm. A factor in their origin is apparently microdamage proliferation (differentiated by en bloc silver staining) with occasional callus moderation. Validation of similar “floating segments” (FS) in the ex-breeder rat suggested a pilot model for a potentially common phenomenon. Following marrow elution and density fractionation of the isolated floating segments from the whole proximal rat femora, scanning electron microscopy (SEM) and elemental microanalysis (EDS) was performed. The eluent contained numbers of vertically truncated, laterally branched floating segments (acute severance of sequential tensile cross-struts, causing chronic compression overload of axial-struts, with ii) inadequate stabilising callus, facilitating ReTm stacking into predetermined, substructural “crumple zones” of force containment, spheroidal attrition and particulate dissociation. As a catabolic outcome of altered tensile and hormonal influence, FS number may add a novel variable to cancellous bone kinetics particularly in women of relevance to fracture predisposition. 展开更多
关键词 Skeletal Fragility MICRODAMAGE Tensile Trabecular disconnection Floating Segments and Bony Spheroids Substructural Crumple Zones SEM and EDS Microanalysis
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Study of the Impact of Grid Disconnections on the Production of a Photovoltaic Solar Power Plant: Case of Diamniadio Power Plant
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作者 Amadou Ndiaye Mohamed Cherif Aidara +1 位作者 Amy Mbaye Mamadou Lamine Ndiaye 《Journal of Power and Energy Engineering》 2023年第6期16-25,共10页
Today, renewable energy projects connected to the interconnected network, with powers of the order of tens of megawatts, are more and more numerous in sub-Saharan Africa. And financing these investments requires a rel... Today, renewable energy projects connected to the interconnected network, with powers of the order of tens of megawatts, are more and more numerous in sub-Saharan Africa. And financing these investments requires a reliable amortization schedule. In the context of photovoltaic systems connected to the interconnected electricity grid, the quintessence of damping is the amount of energy injected into the grid. Thus it is fundamental to know the parameters of this network and their variation. This paper presents an evaluation of the impact of power grid disturbances on the performance of a solar PV plant under real conditions. The CICAD photovoltaic solar plant, connected to the Senelec distribution network, with an installed capacity of 2 MWp is the study setting. An energy audit of the plant is carried out. Then the percentage of each loss is determined: voltage drops, module degradation, inverter efficiency. The duration of each disconnection is measured and recorded daily. The corresponding quantity of lost energy is thus calculated from meteorological data (irradiation, temperature, wind speed, illumination) recorded by the measurement unit in one-minute steps. The observation period is three months. The total duration of disconnections related to the instability of the electrical network during the study period is 46.7 hours. The amount of energy lost is estimated at 22.6 MWh. This represents 2.4% of the actual calculated production. 展开更多
关键词 Photovoltaic Power Plant disconnections Network Evaluation Lost En-ergy
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A Study of Digital Disconnection Among Older Adults in the Internet Age
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作者 JIAO Ruotong 《Psychology Research》 2023年第4期176-181,共6页
With internet and smartphone usage increasing every year,seniors are being exposed to digital media,either actively or passively.To better integrate into the information society for the elderly,efforts are also needed... With internet and smartphone usage increasing every year,seniors are being exposed to digital media,either actively or passively.To better integrate into the information society for the elderly,efforts are also needed to clarify the causes of their digital disconnection and develop appropriate solutions.In this study,semi-structured interviews are utilized to investigate the self-adjustment and external intervention of the elderly in the age of digital media and to explore the ways,causes,and effects of digital disconnection of the elderly.The focus issue of this study is to clarify the subjective and objective factors of digital disconnection,especially cognitive problems,group influences,and technological access barriers in the elderly population concerning digital devices and the Internet. 展开更多
关键词 senior citizens digital disconnect digital divide smartphones
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Modified laparoscopic splenectomy and azygoportal disconnection combined with cell salvage is feasible and might reduce the need for blood transfusion 被引量:16
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作者 Guo-Qing Jiang Dou-Sheng Bai +4 位作者 Ping Chen Jian-Jun Qian Sheng-Jie Jin Jie Yao Xiao-Dong Wang 《World Journal of Gastroenterology》 SCIE CAS 2014年第48期18420-18426,共7页
AIM: To investigate perioperative outcomes in patients undergoing modified laparoscopic splenectomy and azygoportal disconnection (MLSD) with intraoperative autologous cell salvage.
关键词 Portal hypertension LAPAROSCOPY SPLENECTOMY Azygoportal disconnection Cell salvage
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Perioperative advantages of modified laparoscopic vs open splenectomy and azygoportal disconnection 被引量:15
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作者 Guo-Qing Jiang Ping Chen +4 位作者 Jian-Jun Qian Jie Yao Xiao-Dong Wang Sheng-Jie Jin Dou-Sheng Bai 《World Journal of Gastroenterology》 SCIE CAS 2014年第27期9146-9153,共8页
AIM: To investigate perioperative outcomes in patients undergoing modified laparoscopic splenectomy or open splenectomy and azygoportal disconnection for portal hypertension.
关键词 Portal hypertension LAPAROSCOPY SPLENECTOMY Azygoportal disconnection Inflammatory response
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Posterior quadrantic disconnection maintains the activity of isolated temporal-parietal-occipital nerve tissue: neuroprotective measures in the surgical treatment of epilepsy 被引量:4
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作者 Shaoya Yin Keke Feng +2 位作者 Mei Feng Xueqing Zhang Yuqin Zhang 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第4期447-448,共2页
Extensive lesions involving the posterior quadrant of the cerebral hemisphere (temporal, parietal, and occipital lobes) induce intractable epilepsy. These patients are potential candidates for surgical treatmenttu. ... Extensive lesions involving the posterior quadrant of the cerebral hemisphere (temporal, parietal, and occipital lobes) induce intractable epilepsy. These patients are potential candidates for surgical treatmenttu. Maintenance of isolated nerve tissue activity after surgery plays a crucial role in the neuroprotective effects of neurosurgery treatment. Disconnection surgery of the posterior quadrant is used to completely isolate nerve fibers, while blood supply at the isolated lobes is maintained. Subsequently, cavities caused by cystic or necrotic nerve tissues should be reduced as much as possible, 展开更多
关键词 MRI Posterior quadrantic disconnection maintains the activity of isolated temporal-parietal-occipital nerve tissue neuroprotective measures in the surgical treatment of epilepsy EEG Figure
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Basal stacking fault induced twin boundary gliding,twinning disconnection and twin growth in hcp Ti from the first-principles 被引量:3
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作者 Qi QIAN Zheng-qing LIU +3 位作者 Yong JIANG Yi-ren WANG Xing-long AN Min SONG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2021年第2期382-390,共9页
First-principles calculations were performed to investigate the structures and energetics of {101n} coherent twin boundaries(CTBs) and glide twin boundaries(GTBs) in hexagonal close-packed(hcp) Ti. The formation mecha... First-principles calculations were performed to investigate the structures and energetics of {101n} coherent twin boundaries(CTBs) and glide twin boundaries(GTBs) in hexagonal close-packed(hcp) Ti. The formation mechanism of GTBs and their correlation with twin growth were fundamentally explored. Results suggested that GTBs can form from the gliding of CTBs, through their interaction with basal stacking fault. The gliding eventually restored the CTB structures by forming a pair of single-layer twinning disconnections. The pile-up of twinning disconnections should be responsible for the wide steps at twin boundaries as observed in high-resolution transmission electron microscopy, which can further promote twin growth. Possible effects of various alloying elements on pinning twin boundaries were also evaluated, to guide the strengthening design of Ti alloys. 展开更多
关键词 twin boundary stacking fault twinning disconnection twin growth first principles
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Road Lateral Disconnection and Crossing Impacts in River Landscape of Lancang River Valley in Yunnan Province,China 被引量:2
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作者 WANG Cong LIU Shiliang +2 位作者 DENG Li LIU Qi YANG Juejie 《Chinese Geographical Science》 SCIE CSCD 2014年第1期28-38,共11页
Roads are conspicuous components in a river landscape;however,their impacts on river landscape patterns and ecological processes have not been systematically studied at the watershed scale.In this paper,the Lancang Ri... Roads are conspicuous components in a river landscape;however,their impacts on river landscape patterns and ecological processes have not been systematically studied at the watershed scale.In this paper,the Lancang River Valley in Yunnan Province,China was selected as a case to study road lateral disconnection and crossing impacts and identify river-road network interaction.This study was primarily focused on the road impacts on soil erosion intensity and patch density by using GIS analysis at different scales and explored their distribution with terrain factors.The results showed that river density revealed spatial autocorrelation although both of the roads and rivers were distributed unevenly in the valley.The lateral road(road curvature≥1.1)proportion correlated with soil erosion intensity(p 0.01)at the small sub-basin scale.Soil erosion intensity decreased with increasing lateral road buffer width.Light erosion generally accounted for a large proportion of the erosion in the lateral road buffer zones(1.0–4.0 km),while higher class lateral roads imposed greater impacts on soil erosion than lower class roads,which primarily had a moderate erosion level.In addition,the results of road-river intersection density indicated that road crossing impacts were significantly correlated with patch density at the small sub-basin scale.Topography factor(percent of slope>25°in each sub-basin had a close relationship with the ratio of total length of road line with curvature value≥1.1 to the total number of intersections.The correlation(p 0.01)between road impacts and terrain factor revealed that topography affected the road impact distribution in the Lancang River Valley. 展开更多
关键词 lateral disconnection crossing impacts river landscape patch density soil erosion scale effect
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Description of interhemispheric disconnection syndrome in a patient with Marchiafava-Bignami disease
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作者 Daniel Gustavo Politis Romina Mara Tirigay +1 位作者 Pablo Guillermo Gómez María Eugenia Tabernero 《World Journal of Neuroscience》 2013年第3期190-197,共8页
Interhemispheric disconnection syndrome (IDS), described by Sperry, Gazzaniga and Bogen, is characterized by the presence of visual and tactile anomia, absence of interhemispheric transference of unilateral somatosens... Interhemispheric disconnection syndrome (IDS), described by Sperry, Gazzaniga and Bogen, is characterized by the presence of visual and tactile anomia, absence of interhemispheric transference of unilateral somatosensory stimulation of both hands, hemialexia and unilateral left-side apraxia. Subsequently, changes were also observed in the sensory interhemispheric transfer and in tests of crossed motor control. In Marchiafava-Bignami disease (MBD) there have been descriptions of partial IDS. The aim is to describe the dissociations in IDS that are presented in a patient with MBD, using a specialized assessment methodology. Patient and Method: A 54-year-old patient, righthanded, with 11 years of schooling, presented with antecedent chronic alcoholism. Neuropsychological tests were administered for general assessment along with specific tests of interhemispheric transference. Results: Borderline changes were found in visual memory, visual-constructive abilities and attention and executive functioning. In tasks of interhemispheric transference the patient showed changes in: the imitation of hand poses;inter-manual pressure point localization (tactile stimulation);reading aloud of words by visual hemifield;and movement control. Conclusion: Our patient showed a wide lesion of the Corpus Callosum (CC) with relative preservation of the splenium, accompanied by partial disconnection syndrome in the context of a global cognitive deterioration from his chronic alcoholism. 展开更多
关键词 SPLIT-BRAIN Marchiafava-Bignami Disease HEMISPHERIC SPECIALIZATION Tachioscopic Assessment INTERHEMISPHERIC disconnection SYNDROME
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An Analytical Framework for Disconnection Prediction in Wireless Networks
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作者 Gitanjali Bhutani 《International Journal of Communications, Network and System Sciences》 2014年第6期165-174,共10页
The stability and reliability of links in wireless networks is dependent on a number of factors such as the topology of the area, inter-base station or inter-mobile station distances, weather conditions and so on. Lin... The stability and reliability of links in wireless networks is dependent on a number of factors such as the topology of the area, inter-base station or inter-mobile station distances, weather conditions and so on. Link instability in wireless networks has a negative impact on the data throughput and thus, the overall quality of user experience, even in the presence of sufficient bandwidth. An estimation of link quality and link availability duration can drastically increase the performance of these networks, allowing the network or applications to take proactive measures to handle impending disconnections. In this paper we look at a mathematical model for predicting disconnection in wireless networks. This model is originally intended to be implemented in base stations of cellular networks, but is independent of the wireless technology and can thus be applied to different types of networks with minimum changes. 展开更多
关键词 WIRELESS Networks MOBILITY Modeling disconnection PREDICTION
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Integrated risk management: a Petrobras application in offshore well construction safety to minimize critical emergency disconnections 被引量:2
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作者 Claudio Benevenuto de Campos Lima Pedro Esteves Aranha +3 位作者 Jose Francisco Tebaldi de Castro Gilson Brito Alves Lima Augusto Borella Hougaz Felipe de Souza Terra 《Petroleum Science》 SCIE CAS CSCD 2018年第2期421-431,共11页
In order to avoid mistakes and to save a great deal of time in analysis, an innovative methodology was developed that can analyze the well operations and rig characteristics involved to define the best emergency disco... In order to avoid mistakes and to save a great deal of time in analysis, an innovative methodology was developed that can analyze the well operations and rig characteristics involved to define the best emergency disconnect sequence (EDS) available. A solution was developed based on the characteristics of the rigs and blowout preventers (BOPs), and six variables were considered that directly affect the choice of EDS. All possible combinations of 64 scenarios were analyzed, and the priority of choice of the EDS was defined empirically. This paper presents an approach to EDS risk management and examples of exposure time (time without riser safety margin and shear capability) for the same well, which can be lowered from 13% to 0.1%. The impact of this reduction is related to the ability of the BOP to cut some of the heavy casings, in addition to improved availability of EDS modes. This implementation opened up many possibilities for the performance of risk exposure analysis, enabling comparison of several BOP configurations of contracted rigs and selection of the best options. This innovative approach allowed a better management of the rig schedules, prioritizing safety aspects and making it possible to allocate the fleet in a systematic way. 展开更多
关键词 Well safety Safety barriers Emergency disconnect sequence (EDS) Well control Kick Well design
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Enhanced DDoS Detection Using Advanced Machine Learning and Ensemble Techniques in Software Defined Networking
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作者 Hira Akhtar Butt Khoula Said Al Harthy +3 位作者 Mumtaz Ali Shah Mudassar Hussain Rashid Amin Mujeeb Ur Rehman 《Computers, Materials & Continua》 SCIE EI 2024年第11期3003-3031,共29页
Detecting sophisticated cyberattacks,mainly Distributed Denial of Service(DDoS)attacks,with unexpected patterns remains challenging in modern networks.Traditional detection systems often struggle to mitigate such atta... Detecting sophisticated cyberattacks,mainly Distributed Denial of Service(DDoS)attacks,with unexpected patterns remains challenging in modern networks.Traditional detection systems often struggle to mitigate such attacks in conventional and software-defined networking(SDN)environments.While Machine Learning(ML)models can distinguish between benign and malicious traffic,their limited feature scope hinders the detection of new zero-day or low-rate DDoS attacks requiring frequent retraining.In this paper,we propose a novel DDoS detection framework that combines Machine Learning(ML)and Ensemble Learning(EL)techniques to improve DDoS attack detection and mitigation in SDN environments.Our model leverages the“DDoS SDN”dataset for training and evaluation and employs a dynamic feature selection mechanism that enhances detection accuracy by focusing on the most relevant features.This adaptive approach addresses the limitations of conventional ML models and provides more accurate detection of various DDoS attack scenarios.Our proposed ensemble model introduces an additional layer of detection,increasing reliability through the innovative application of ensemble techniques.The proposed solution significantly enhances the model’s ability to identify and respond to dynamic threats in SDNs.It provides a strong foundation for proactive DDoS detection and mitigation,enhancing network defenses against evolving threats.Our comprehensive runtime analysis of Simultaneous Multi-Threading(SMT)on identical configurations shows superior accuracy and efficiency,with significantly reduced computational time,making it ideal for real-time DDoS detection in dynamic,rapidly changing SDNs.Experimental results demonstrate that our model achieves outstanding performance,outperforming traditional algorithms with 99%accuracy using Random Forest(RF)and K-Nearest Neighbors(KNN)and 98%accuracy using XGBoost. 展开更多
关键词 Table 1(continued)OSI layer Possible DDoS attack Data link MAC Address Flooding Physical Cable disconnection JaMMING physical impersonation
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Retroperitoneoscopic renal pedical lymphatic disconnection in the treatment of chyluria 被引量:14
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作者 XIA Guo-wei DING Qiang YU Jiang XU Ke ZHANG Yuan-fang 《Chinese Medical Journal》 SCIE CAS CSCD 2008年第15期1478-1480,共3页
Chyluria is a disease that may severely debilitate a patient's health condition. Some investigations have indicated that in patients with chyluria, part of the uptake fat and protein leaks from the urine.Thus, recurr... Chyluria is a disease that may severely debilitate a patient's health condition. Some investigations have indicated that in patients with chyluria, part of the uptake fat and protein leaks from the urine.Thus, recurrent chyluria may result in malnutrition. In addition, with nearly one half of the body's the urine, depressed regulatory lymphocytes lost through functions of the lymphatic system may cause illnesses following immune deficiency. Therefore, it is imperative to provide effective and active medical care for chyluria patients. The purpose of surgical treatment is to eliminate lymphatic fistula and decrease intralymphatic pressure. We recently performed retroperitoneoscopic renal pedical lymphatic disconnection for 78 cases of chyluria patients in our hospital between April 2003 and June 2007. We herein summarize our experience as follows. 展开更多
关键词 CHYLURIA RETROPERITONEOSCOPY renal pedical lymphatic disconnection
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Atomistic dynamics of disconnection-mediated grain boundary plasticity:A case study of gold nanocrystals 被引量:3
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作者 Qi Zhu Haofei Zhou +4 位作者 Yingbin Chen Guang Cao Chuang Deng Ze Zhang Jiangwei Wang 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2022年第30期182-191,共10页
Grain boundary(GB)mediated deformation is a vital contributor to the plasticity of polycrystalline materials,where the disconnection model has become a widely recognized approach to depict the GB dynamics.However,expe... Grain boundary(GB)mediated deformation is a vital contributor to the plasticity of polycrystalline materials,where the disconnection model has become a widely recognized approach to depict the GB dynamics.However,experimental understanding of the atomistic disconnection dynamics remains scarce.In this case study of gold nanocrystals,atomistic disconnection dynamics governing the shear-coupled migration of flat GBs have been systematically investigated via in situ transmission electron microscopy nanomechanical testing supported by molecular dynamics simulations.Specifically,the site-dependent nucleation,shear-driven propagation,and diverse interactions associated with distinct GB disconnections are systematically elucidated and quantitatively compared.Moreover,the disconnection-mediated GB plasticity proves to prevail among different tilt and mixed GBs in gold.Eventually,a conceptual map of disconnection-mediated GB dynamics is established,which would furnish a unified understanding of GB plasticity in metallic materials. 展开更多
关键词 Grain boundaries(GBs) disconnection dynamics Plastic deformation In situ transmission electron microscopy(TEM) Metallic materials
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Heuristic Expanding Disconnected Graph:A Rapid Path Planning Method for Mobile Robots
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作者 Yong Tao Lian Duan +3 位作者 He Gao Yufan Zhang Yian Song Tianmiao Wang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第2期68-82,共15页
Existing mobile robots mostly use graph search algorithms for path planning,which suffer from relatively low planning efficiency owing to high redundancy and large computational complexity.Due to the limitations of th... Existing mobile robots mostly use graph search algorithms for path planning,which suffer from relatively low planning efficiency owing to high redundancy and large computational complexity.Due to the limitations of the neighborhood search strategy,the robots could hardly obtain the most optimal global path.A global path planning algorithm,denoted as EDG*,is proposed by expanding nodes using a well-designed expanding disconnected graph operator(EDG)in this paper.Firstly,all obstacles are marked and their corners are located through the map pre-processing.Then,the EDG operator is designed to find points in non-obstruction areas to complete the rapid expansion of disconnected nodes.Finally,the EDG*heuristic iterative algorithm is proposed.It selects the candidate node through a specific valuation function and realizes the node expansion while avoiding collision with a minimum offset.Path planning experiments were conducted in a typical indoor environment and on the public dataset CSM.The result shows that the proposed EDG*reduced the planning time by more than 90%and total length of paths reduced by more than 4.6%.Compared to A*,Dijkstra and JPS,EDG*does not show an exponential explosion effect in map size.The EDG*showed better performance in terms of path smoothness,and collision avoidance.This shows that the EDG*algorithm proposed in this paper can improve the efficiency of path planning and enhance path quality. 展开更多
关键词 Global path planning Mobile robot Expanding disconnected graph Edge node OFFSET
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Endoscopic pancreatogastric anastomosis in the treatment of symptoms associated with inflammatory diseases of the pancreas
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作者 Mateusz Jagielski Eryk Bella Marek Jackowski 《World Journal of Gastrointestinal Endoscopy》 2024年第7期406-412,共7页
BACKGROUND The outflow of pancreatic juice into the duodenum is often impaired in pancreatic inflammatory diseases.The basis of interventional treatment in these cases is anatomical transpapillary access of the main p... BACKGROUND The outflow of pancreatic juice into the duodenum is often impaired in pancreatic inflammatory diseases.The basis of interventional treatment in these cases is anatomical transpapillary access of the main pancreatic duct during endoscopic retrograde cholangiopancreatography(ERCP),which ensures the physiological outflow of pancreatic juice into the lumen of the digestive tract.However,in some patients,anatomical changes prevent transpapillary drainage of the main pancreatic duct.Surgery is the treatment of choice in such cases.AIM To evaluate the effectiveness and safety of endoscopic pancreaticogastrostomy under endoscopic ultrasound(EUS)guidance.METHODS Retrospective analysis of treatment outcomes of all patients with acute or chronic pancreatitis who underwent endoscopic pancreatogastric anastomosis under EUS guidance in 2018-2023 at the Department of General,Gastroenterological and Oncological Surgery,Ludwik Rydygier Collegium Medicum in Bydgoszcz,Nicolaus Copernicus University in Toruń,Poland.RESULTS In 9 patients[7 men,2 women;mean age 53.45(36-66)years],endoscopic pancreatogastric anastomosis under EUS guidance was performed because of the lack of transpapillary access during ERCP.Narrowing of the main pancreatic duct at the head of the pancreas was observed in 4/9 patients(44.44%).Pancreatic fragmentation(disconnected pancreatic duct syndrome)was diagnosed in 3/9 patients(33.33%).In 2/9 patients(22.22%),narrowing of the pancreatoenteric anastomosis was observed after pancreaticoduodenectomy.Technical success of endoscopic pancreaticogastrostomy was observed in 8/9 patients(88.89%).Endotherapeutic complications were observed in 2/9 patients(22.22%).Clinical success was achieved in 8/9 patients(88.89%).The mean follow-up period was 451(42-988)d.Long-term success of endoscopic pancreatogastric anastomosis was achieved in 7/9 patients(77.78%).CONCLUSION Endoscopic pancreaticogastrostomy under EUS guidance is an effective and safe treatment method,especially in the absence of transpapillary access to the main pancreatic duct. 展开更多
关键词 PANCREATICOGASTROSTOMY Chronic pancreatitis Acute pancreatitis Disconnected pancreatic duct syndrome Endotherapy
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Bounds for the Rainbow Disconnection Numbers of Graphs
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作者 Xu Qing BAI Zhong HUANG Xue Liang LI 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2022年第2期384-396,共13页
An edge-cut of an edge-colored connected graph is called a rainbow cut if no two edges in the edge-cut are colored the same.An edge-colored graph is rainbow disconnected if for any two distinct vertices u and v of the... An edge-cut of an edge-colored connected graph is called a rainbow cut if no two edges in the edge-cut are colored the same.An edge-colored graph is rainbow disconnected if for any two distinct vertices u and v of the graph,there exists a rainbow cut separating u and v.For a connected graph G,the rainbow disconnection number of G,denoted by rd(G),is defined as the smallest number of colors required to make G rainbow disconnected.In this paper,we first give some upper bounds for rd(G),and moreover,we completely characterize the graphs which meet the upper bounds of the NordhausGaddum type result obtained early by us.Secondly,we propose a conjecture that for any connected graph G,either rd(G)=λ^(+)(G)or rd(G)=λ^(+)(G)+1,whereλ^(+)(G)is the upper edge-connectivity,and prove that the conjecture holds for many classes of graphs,which supports this conjecture.Moreover,we prove that for an odd integer k,if G is a k-edge-connected k-regular graph,thenχ’(G)=k if and only if rd(G)=k.It implies that there are infinitely many k-edge-connected k-regular graphs G for which rd(G)=λ^(+)(G)for odd k,and also there are infinitely many k-edge-connected k-regular graphs G for which rd(G)=λ^(+)(G)+1 for odd k.For k=3,the result gives rise to an interesting result,which is equivalent to the famous Four-Color Problem.Finally,we give the relationship between rd(G)of a graph G and the rainbow vertex-disconnection number rvd(L(G))of the line graph L(G)of G. 展开更多
关键词 EDGE-COLORING EDGE-CONNECTIVITY rainbow disconnection coloring(number) line graph
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