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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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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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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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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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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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浅议欧盟/欧共体对外条约中的“断开条款(disconnection clause)”
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作者 叶研 《齐齐哈尔大学学报(哲学社会科学版)》 2018年第3期89-93,共5页
欧盟法意义上的"断开条款"是指欧盟/欧共体在对外订立条约时就规定的、在共同体成员国之间适用欧盟/欧共体条款而非公约的一类特殊条款。该条款目前被作为一种格式化条款在欧盟对外条约中得到经常性的运用,它保障了欧盟内部... 欧盟法意义上的"断开条款"是指欧盟/欧共体在对外订立条约时就规定的、在共同体成员国之间适用欧盟/欧共体条款而非公约的一类特殊条款。该条款目前被作为一种格式化条款在欧盟对外条约中得到经常性的运用,它保障了欧盟内部法制的统一和欧盟法律的最高性,但却对欧盟的对外关系、人权公约和国际法本身带来了一些负面影响,因此需要在实践中对该条款的适用进行平衡和个案分析。 展开更多
关键词 断开条款 欧盟法 条约法
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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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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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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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Integrated risk management: a Petrobras application in offshore well construction safety to minimize critical emergency disconnections 被引量:1
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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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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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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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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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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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Layer stacked SiO_(x) microparticle with disconnected interstices enables stable interphase and particle integrity for lithium-ion batteries
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作者 Yang Ren Xucai Yin +4 位作者 Lizhi Xiang Rang Xiao Hua Huo Geping Yin Chunyu Du 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第11期300-307,I0007,共9页
Severe mechanical fractu re and unstable interphase,associated with the large volumetric expansion/contraction,significantly hinder the application of high-capacity SiO_(x)materials in lithium-ion batteries.Herein,we ... Severe mechanical fractu re and unstable interphase,associated with the large volumetric expansion/contraction,significantly hinder the application of high-capacity SiO_(x)materials in lithium-ion batteries.Herein,we report the design and facile synthesis of a layer stacked SiO_(x)microparticle(LS-SiO_(x))material,which presents a stacking structure of SiO_(x)layers with abundant disconnected interstices.This LS-SiO_(x)microparticle can effectively accommodate the volume expansion,while ensuring negligible particle expansion.More importantly,the interstices within SiO_(x)microparticle are disconnected from each other,which efficiently prevent the electrolyte from infiltration into the interior,achieving stable electrode/-electrolyte interface.Accordingly,the LS-SiO_(x)material without any coating delivers ultrahigh average Coulombic efficiency,outstanding cycling stability,and full-cell applicability.Only 6 cycles can attain>99.92%Coulombic efficiency and the capacity retention at 0.05 A g^(-1)for 100 cycles exceeds99%.After 800 cycles at 1 A g^(-1),the thickness swelling of LS-SiO_(x)electrode is as low as 0.87%.Moreover,the full cell with pure LS-SiO_(x)anode exhibits capacity retention of 91.2%after 300 cycles at 0.2 C.This work provides a novel concept and effective approach to rationally design silicon-based and other electrode materials with huge volume variation for electrochemical energy storage applications. 展开更多
关键词 Lithium-ion batteries Silicon oxide Layer stacked structure disconnected interstices Coulombic efficiency
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基于ParFlow.CLM的居民小区屋顶雨水断接水文效应研究
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作者 王瑶 王卫光 张翔 《中国农村水利水电》 北大核心 2024年第9期181-187,195,共8页
城市不透水面的快速扩张极大地改变了自然的水文循环过程,是造成城市内涝、河湖生态退化等城市水问题的主要原因之一。海绵城市建设及低影响开发利用源头海绵设施或城市绿地断接城市不透水面,减少不透水面的水文效应,是缓解城市水问题... 城市不透水面的快速扩张极大地改变了自然的水文循环过程,是造成城市内涝、河湖生态退化等城市水问题的主要原因之一。海绵城市建设及低影响开发利用源头海绵设施或城市绿地断接城市不透水面,减少不透水面的水文效应,是缓解城市水问题的重要措施。探究不透水面断接的水文效应对我国海绵城市建设具有重要意义。基于全分布式物理水文模型ParFlow.CLM,充分考虑城市地下构筑物,探究了不同土壤质地情景下西宁市某典型居民小区建筑屋顶断接在连续的降雨、蒸发过程中的水文效应。模拟结果显示,利用该居民小区自然绿地断接建筑屋顶能取得较好的径流控制效果:当土壤饱和导水率(K_(s))大于0.01m/h时,屋顶径流的年削减率能达到72.9%以上。屋顶断接在建筑物雨落管附近形成了集中入渗,增加了根区土壤湿度,且这一效应随着土壤渗透性的增加而增强。根区土壤湿度的增加进一步促进了绿地的蒸散发:与屋顶断接前相比,不同土壤质地情景下居民小区年蒸散发总量增加了6.2%~7.8%。另一方面,集中入渗在局部也形成了更深的湿润锋,使得更多下渗水量能够脱离植被根区的蒸散发作用,从而促进根区水分的深层渗漏。模拟结果表明,尽管该居民小区地下停车场限制了大部分区域的深层渗漏,当土壤K_(s)大于0.01m/h时,屋顶断接情景下的年深层渗漏总量仍能超过城市化前的水平。 展开更多
关键词 不透水面断接 海绵城市 低影响开发 ParFlow.CLM 城市地下构筑物
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非连通空间对象方向关系表达与推理
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作者 王淼 董星星 +3 位作者 高继勋 方振西 唐昊 李松 《计算机应用研究》 CSCD 北大核心 2024年第9期2655-2663,共9页
为了弥补现有的二维空间对象方向关系表达模型大都利用点、最小外包矩形等近似地代替空间对象,距离真实空间对象间方向关系的描述与推理仍存在差距的不足,提出了一种基于Voronoi图的非连通空间对象方向关系表达模型。该模型借助Gestalt... 为了弥补现有的二维空间对象方向关系表达模型大都利用点、最小外包矩形等近似地代替空间对象,距离真实空间对象间方向关系的描述与推理仍存在差距的不足,提出了一种基于Voronoi图的非连通空间对象方向关系表达模型。该模型借助Gestalt心理学理论,通过提取非连通空间对象的特征点、特征链,构建空间对象间的可视区域,生成方向关系Voronoi图,实现了非连通、含洞的参考对象与目标对象间方向关系的表达。该模型较好地顾及了空间对象形状、大小等因素带来的影响,表达精度更高、适用范围更广。为了提高复杂空间对象方向关系复合推理的精度,基于该模型提出了一个非连通对象间主方向关系复合推理算法。该算法借助Tile-union运算和Pr运算,实现了该模型下基本主方向关系的复合推理,降低推理结果的不确定性。分析和验证的结果表明,提出的非连通空间对象方向关系模型及复合推理算法,提高了表达与推理的精度,完善和提高了对复杂空间对象方位关系的分析与处理能力。 展开更多
关键词 VORONOI图 Gestalt心理学理论 非连通空间对象 主方向关系 复合推理
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多间隔信息融合的母线保护电流互感器断线再开放策略
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作者 陈琦 陈福锋 +4 位作者 唐治国 薛明军 刘凯祥 王胜 孙震宇 《电力自动化设备》 EI CSCD 北大核心 2024年第5期151-157,共7页
对于电流互感器(CT)断线后发生金属性故障的情景,现有母线保护采取的闭锁差动保护动作方式将会引发多个变电站停电。此外,当母线区内发生高阻接地故障时,现有母线保护判据可能会将其误判为CT断线故障,不利于电力系统的安全稳定运行。针... 对于电流互感器(CT)断线后发生金属性故障的情景,现有母线保护采取的闭锁差动保护动作方式将会引发多个变电站停电。此外,当母线区内发生高阻接地故障时,现有母线保护判据可能会将其误判为CT断线故障,不利于电力系统的安全稳定运行。针对这一问题,提出了一种母线保护CT断线再开放策略,该策略基于断线间隔与非断线间隔的零序电流变化量对负荷波动和故障进行区分,并基于非断线间隔的差流有效值和间隔失灵保护信息对区内外故障进行判别。实时数字仿真系统仿真结果验证了所提CT断线识别判据和再开放策略的正确性。 展开更多
关键词 电流互感器断线 多间隔信息融合 短路故障 电流互感器闭锁策略 母线保护
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