MXenes are a novel family of two-dimensional(2D)materials that are fast gaining popularity due to their versatile characteristics.The surfaces of these materials are often functionalized by negatively charged terminal...MXenes are a novel family of two-dimensional(2D)materials that are fast gaining popularity due to their versatile characteristics.The surfaces of these materials are often functionalized by negatively charged terminal groups,such as=O,OH,and F during their synthesis,and it has been hypothesized that regulating the surface terminators enables to control the material characteristics.However,there is still a large gap between computational and experimental investigations regarding comprehending the surface functional groups.Surfaces with mixed terminations are consistently synthesized in experiments,although pure terminated surfaces are predicted by computational research.Here we summarized the nature of chemical bonding in transition metal carbide materials(MXenes)by1H and19F nuclear magnetic resonance(NMR),Raman,X-ray absorption near edge structure(XANES),extended X-ray absorption fine structure(EXAFS),ultraviolet photoelectron spectroscopy(UPS),X-ray photoelectron spectroscopy(XPS)/scanning transmission electron microscopy(STEM),and thermogravimetric analysis-mass spectrometry(TGA-MS)characterizations.Previous literature reveals that=O,–OH,–F,and–Cl are typical MXene surface terminators.However,recent comparative investigations on the valence band intensity distribution in MXenes reveal that the–OH cannot be considered an intrinsic termination species in MXenes.The surface terminals(=O,–OH,–F,and–Cl)of several MXenes,particularly V2CTxand Ti3C2Tx,will be identified and quantified here.We have also discussed different etching approaches for the synthesis of MXene,the dependence of MXene conductivity on MXene terminating groups,and the emission of various gaseous products that evolved during its chemical transformations.This paper provides significance,especially in the field of energy conversion and storage materials,where the intercalation process is crucial.展开更多
Two 2-aryl imidazo [2,1-a] isoquinolines were synthesized and tested for pregnancy terminating activities. Both of them are new compounds and their structures were confirmed by IR, (HNMR)-H-1, MS and elemental analysi...Two 2-aryl imidazo [2,1-a] isoquinolines were synthesized and tested for pregnancy terminating activities. Both of them are new compounds and their structures were confirmed by IR, (HNMR)-H-1, MS and elemental analysis. They both showed high activities in NIH mice.展开更多
In order to clarify the structural requirement of pregnancy-terminating drugs, the quantitative structure-activity relationship (QSAR) of 2-aryl imidazo[2,1-a]isoquinolines was studied on the basis of quantum mechanic...In order to clarify the structural requirement of pregnancy-terminating drugs, the quantitative structure-activity relationship (QSAR) of 2-aryl imidazo[2,1-a]isoquinolines was studied on the basis of quantum mechanical calculation and multiple regression analysis. A Good correlation equation was obtained (r2=0.925, q2=0.871). Some new compounds were designed according to the equation. Two of them, compounds 21 and 22, were synthesized and evaluated in NIH mice. The results showed that the difference of activity between 21 (median effective dose ED50=0.943 mg/kg/day) and 22 (ED50=1.099 mg/kg/day) was small and both of them were potent. It is also agreed with the computational results. Compared with L14105 which is the most potent pregnancy-terminating agent, these two compounds possess high activity. The evaluation of the anti-implanting activity showed that they were 100% effective at tested dosage 50.0, 25.0, 12.5 mg/kg/day×3 days in oral administration, which proved the both of them had anti-implanting activity and low first-pass effects.展开更多
This work presents a systematic analysis of proton-induced total ionizing dose(TID)effects in 1.2 k V silicon carbide(SiC)power devices with various edge termination structures.Three edge terminations including ring-a...This work presents a systematic analysis of proton-induced total ionizing dose(TID)effects in 1.2 k V silicon carbide(SiC)power devices with various edge termination structures.Three edge terminations including ring-assisted junction termination extension(RA-JTE),multiple floating zone JTE(MFZ-JTE),and field limiting rings(FLR)were fabricated and irradiated with45 Me V protons at fluences ranging from 1×10^(12) to 1×10^(14) cm^(-2).Experimental results,supported by TCAD simulations,show that the RA-JTE structure maintained stable breakdown performance with less than 1%variation due to its effective electric field redistribution by multiple P+rings.In contrast,MFZ-JTE and FLR exhibit breakdown voltage shifts of 6.1%and 15.2%,respectively,under the highest fluence.These results demonstrate the superior radiation tolerance of the RA-JTE structure under TID conditions and provide practical design guidance for radiation-hardened Si C power devices in space and other highradiation environments.展开更多
The Western Sichuan Foreland Basin(WSFB)in South China,a prolific hydrocarbon province,exhibits complex structural deformation influenced by Triassic salt tectonics.This paper integrates seismic data and well data to ...The Western Sichuan Foreland Basin(WSFB)in South China,a prolific hydrocarbon province,exhibits complex structural deformation influenced by Triassic salt tectonics.This paper integrates seismic data and well data to elucidate the role of Middle-Lower Triassic evaporite layers in shaping basin structures,focusing on Xinchang Tectonic Zone(XTZ).Salt layers facilitated decoupled deformation between supra-and sub-salt sequences,forming salt pillows and fault-related folds.Three distinct structural trends were identified in XTZ.Key findings reveal that salt thickness variations correlate with deformation styles:thicker salt promoted detachment folding,while thinner salt led to hard-linked fault systems.Sub-salt E-NE trending reverse faults formed horsetail terminations associated with the Pengzhou faults(PzF),deviating from the primary Longmenshan thrust belt(LmsTB)orientation.Structural evolution occurred in three stages:(1)Indosinian salt deposition and foreland basin initiation;(2)Yanshanian eastward propagation of thrust systems with salt-driven detachment folding;(3)Himalayan reactivation overprinting earlier structures with sub-NS trending folds.This work establishes a direct link between salt layers and structural traps,demonstrating how salt acted as a critical detachment layer during multi-stage compression.Results provide insights into the gas exploration of the Late Triassic Xujiahe Formation,emphasizing the importance of salt-influenced deformation in foreland basin systems.展开更多
To explore the best preparation process for terminal blend(TB)composite-modified asphalt and to filter its formulation with excellent performance,this study evaluates the performance of TB composite modified asphalt b...To explore the best preparation process for terminal blend(TB)composite-modified asphalt and to filter its formulation with excellent performance,this study evaluates the performance of TB composite modified asphalt by physical property index,microscopic morphology,rheological testing,and infrared spectroscopy on multiple scales.The results show that the best preparation process for TB-modified asphalt is stirring at 260℃ for 4 h at 400 rpm,which significantly reduces the modification time of the asphalt.From a physical property viewpoint,the TB composite-modified asphalt sample with 5% styrene-butadiene-styrene(SBS)+1% aromatics+0.1% sulfur exhibits high-comprehensive,high-and low-temperature properties.More-over,its crosslinked mesh structure comprises black rubber particles uniformly interwoven in the middle,which further enhances the performance of the asphalt and results in an excellent performance formulation.In addition,the sample with 5%SBS content has a higher G*value and smaller δ value than that with 3%SBS content,indicating that its high-temperature resistance is improved.The effect of adding 3%SBS content on the viscoelastic ratio is,to some extent,less than that caused by 20% rubber powder.展开更多
This paper investigates the termination problems of multi-path polynomial programs （MPPs） with equational loop guards. To establish sufficient conditions for termination and nontermination simultaneously, the author...This paper investigates the termination problems of multi-path polynomial programs （MPPs） with equational loop guards. To establish sufficient conditions for termination and nontermination simultaneously, the authors propose the notion of strong/weak non-termination which under/over- approximates non-termination. Based on polynomial ideal theory, the authors show that the set of all strong non-terminating inputs （SNTI） and weak non-terminating inputs （WNTI） both correspond to tile real varieties of certain polynomial ideals. Furthermore, the authors prove that the variety of SNTI is computable, and under some sufficient conditions the variety of WNTI is also computable. Then by checking the computed SNTI and WNTI varieties in parallel, termination properties of a consid- ered MPP can be asserted. As a consequence, the authors establish a new framework for termination analysis of MPPs.展开更多
We define here the concept of head boundedness,head normal form and head confluence of term rewriting systems that allow infinite derivations.Head confluence is weaker than confluence,but suffi- cient to guarantee the...We define here the concept of head boundedness,head normal form and head confluence of term rewriting systems that allow infinite derivations.Head confluence is weaker than confluence,but suffi- cient to guarantee the correctness of lazy implementations of equational logic programming languages. Then we prove several results.First,if a left-linear system is locally confluent and head-bounded,then it is head-confluent.Second,head-confluent and head-bounded systems have the head Church-Rosser proper- ty.Last,if an orthogonal system is head-terminating,then it is bead-bounded.These results can be ap- plied to generalize equational logic programming languages.展开更多
Peripheral nerve injuries result in the rapid degeneration of distal nerve segments and immediate loss of motor and sensory functions;behavioral recovery is typically poor.We used a plasmalemmal fusogen,polyethylene g...Peripheral nerve injuries result in the rapid degeneration of distal nerve segments and immediate loss of motor and sensory functions;behavioral recovery is typically poor.We used a plasmalemmal fusogen,polyethylene glycol(PEG),to immediately fuse closely apposed open ends of severed proximal and distal axons in rat sciatic nerves.We have previously reported that sciatic nerve axons repaired by PEG-fusion do not undergo Wallerian degeneration,and PEG-fused animals exhibit rapid(within 2–6 weeks)and extensive locomotor recovery.Furthermore,our previous report showed that PEG-fusion of severed sciatic motor axons was non-specific,i.e.,spinal motoneurons in PEG-fused animals were found to project to appropriate as well as inappropriate target muscles.In this study,we examined the consequences of PEG-fusion for sensory axons of the sciatic nerve.Young adult male and female rats(Sprague–Dawley)received either a unilateral single cut or ablation injury to the sciatic nerve and subsequent repair with or without(Negative Control)the application of PEG.Compound action potentials recorded immediately after PEG-fusion repair confirmed conduction across the injury site.The success of PEG-fusion was confirmed through Sciatic Functional Index testing with PEG-fused animals showing improvement in locomotor function beginning at 35 days postoperatively.At 2–42 days postoperatively,we anterogradely labeled sensory afferents from the dorsal aspect of the hindpaw following bilateral intradermal injection of wheat germ agglutinin conjugated horseradish peroxidase.PEG-fusion repair reestablished axonal continuity.Compared to unoperated animals,labeled sensory afferents ipsilateral to the injury in PEG-fused animals were found in the appropriate area of the dorsal horn,as well as inappropriate mediolateral and rostrocaudal areas.Unexpectedly,despite having intact peripheral nerves,similar reorganizations of labeled sensory afferents were also observed contralateral to the injury and repair.This central reorganization may contribute to the improved behavioral recovery seen after PEG-fusion repair,supporting the use of this novel repair methodology over currently available treatments.展开更多
This article investigates the anti-disturbance and stabilization problems for the nonlinear uncertain permanent magnet synchronous motor(PMSM)with stator voltage saturation and unknown load.A smooth switching mechanis...This article investigates the anti-disturbance and stabilization problems for the nonlinear uncertain permanent magnet synchronous motor(PMSM)with stator voltage saturation and unknown load.A smooth switching mechanism is presented to structure the adaptive integral terminal sliding mode control(SMC)strategy.The control design consists of compensation control and nominal control,which improves the rapidity and accuracy of trajectory tracking.The smooth saturation model based on the error function is applied to approximate the voltage saturation phenomenon.Additionally,to deal with the adverse effects of various unknown disturbances,including model parameter uncertainties and unknown external load disturbances,an improved disturbance observer(DO)is proposed.This observer effectively suppresses the fluctuations caused by fixed gain during the starting period of the system.Finally,the experimental results under different conditions show that the proposed strategy has good tracking and disturbance suppression performances.展开更多
This paper presents a robust finite-time visual servo control strategy for the tracking problem of omni-directional mobile manipulators(OMMs)subject to mismatched disturbances.First,the nonlinear kinematic model of vi...This paper presents a robust finite-time visual servo control strategy for the tracking problem of omni-directional mobile manipulators(OMMs)subject to mismatched disturbances.First,the nonlinear kinematic model of visual servoing for OMMs with mismatched disturbances is explicitly presented to solve the whole-body inverse kinematic problem.Second,a sliding mode observer augmented with an integral terminal sliding mode controller is proposed to handle these uncertainties and ensure that the system converges to a small region around the equilibrium point.The boundary layer technique is employed to mitigate the chattering phenomenon.Furthermore,a strict finite-time Lyapunov stability analysis is conducted.An experimental comparison between the proposed algorithm and a traditional position-based visual servo controller is carried out,and the results demonstrate the superiority of the proposed control algorithm.展开更多
Construction of LNG receiving terminals The scale of receiving terminals is expanding rapidly At the end of 1999,the state approved the Guangdong LNG Pilot Project,which opened the prelude to the construction of LNG r...Construction of LNG receiving terminals The scale of receiving terminals is expanding rapidly At the end of 1999,the state approved the Guangdong LNG Pilot Project,which opened the prelude to the construction of LNG receiving terminals.In 2006,China's first LNG receiving terminal,namely Dapeng LNG Receiving Terminal in Shenzhen,Guangdong Province,was put into operation,marking the beginning of the use of overseas natural gas in China.展开更多
BACKGROUND Children with critical acute abdominal conditions often undergo intestinal stoma surgery.AIM To explore the impact of a visual mobile terminal-based extended care model on caregiver competence for children ...BACKGROUND Children with critical acute abdominal conditions often undergo intestinal stoma surgery.AIM To explore the impact of a visual mobile terminal-based extended care model on caregiver competence for children with enterostomies.METHODS One hundred twenty children with enterostomies and their caregivers in a children's hospital in Beijing were divided into a control group and a study group.The control group(60 cases)received traditional telephone follow-up for continuity of care,while the study group(60 cases)used a visualization mobile terminal-based care model.The incidence of stoma-related complications,caregiver burden scale,and competence scores of children with stoma were compared between the two groups.RESULTS The primary caregiver burden score in the study group(37.22±3.17)was significantly lower than that in the control group(80.00±4.47),and the difference was statistically significant(P<0.05).Additionally,the caregiving ability score of the study group(172.08±3.49)was significantly higher than that of the control group(117.55±4.28;P<0.05).The total incidence of complications in the study group(11.7%,7/60)was significantly lower compared to the control group(33.3%,20/60;χ2=8.086,P=0.004).CONCLUSION The visual mobile terminal-based care model reduces caregiver burden,improves home care ability,lowers the incidence of complications and readmission rates,and supports successful second-stage reduction surgery for children with enterostomies.展开更多
In this paper,an improved error-rate sliding window decoder is proposed for spatially coupled low-density parity-check(SC-LDPC)codes.For the conventional sliding window decoder,the message retention mechanism causes u...In this paper,an improved error-rate sliding window decoder is proposed for spatially coupled low-density parity-check(SC-LDPC)codes.For the conventional sliding window decoder,the message retention mechanism causes unreliable messages along the edges of belief propagation(BP)decoding in the current window to be kept for subsequent window decoding.To improve the reliability of the retained messages during the window transition,a reliable termination method is embedded,where the retained messages undergo more reliable parity checks.Additionally,decoding failure is unavoidable and even causes error propagation when the number of errors exceeds the error-correcting capability of the window.To mitigate this problem,a channel value reuse mechanism is designed,where the received channel values are utilized to reinitialize the window.Furthermore,considering the complexity and performance of decoding,a feasible sliding optimized window decoding(SOWD)scheme is introduced.Finally,simulation results confirm the superior performance of the proposed SOWD scheme in both the waterfall and error floor regions.This work has great potential in the applications of wireless optical communication and fiber optic communication.展开更多
The approximately 3000 km long Tan-Lu fault zone(TLFZ)in East Asia is the longest continental strike-slip fault zone in the world and exemplifies how such a fault zone forms and propagates on a continental scale.Struc...The approximately 3000 km long Tan-Lu fault zone(TLFZ)in East Asia is the longest continental strike-slip fault zone in the world and exemplifies how such a fault zone forms and propagates on a continental scale.Structural and geochronological data from the TLFZ and surrounding regions indicate that the fault zone originated as NE/SW-striking sinistral ductile shear zones along an oblique continental convergence margin during the Triassic indentation collision between the North China Craton and the Yangtze Block.The Triassic fault zone,with a total length of about 720 km between the Dabie and Sulu orogens,exhibited an apparent sinistral offset of approximately 300 km along the TLFZ.The second stage of sinistral movement occurred in the earliest Late Jurassic,reactivating the pre-existing southern segment and propagating northwards to the southern coastline of present-day Bohai Bay,as well as forming a significant portion of the Dunhua-Mishan fault zone.The third stage of sinistral movement,in the earliest Early Cretaceous,was the most intense strike-slip movement of the Mesozoic,leading to the complete linkage of the TLFZ.This stage included further northward propagation of the southern-middle segment,both southward and northward propagation of the Dunhua-Mishan fault zone,as well as the formation of the entire Yilan-Yitong fault zone.The fourth stage,in the earliest Late Cretaceous,involved the reactivation of the entire TLFZ.Following its Triassic origin due to the indentation collision,the subduction of the Paleo-Pacific Plate and the subduction and closure of the Mongol-Okhotsk Ocean were responsible for the multi-stage sinistral movements from the Late Jurassic to the Cretaceous.The evolution of the TLFZ demonstrates that a continental-scale strike-slip fault zone(>1000 km long)forms through multiple stages of propagation and linkage in dynamic settings of plate convergence.展开更多
基金supported by the National Natural Science Foundation of China(21703147 and U1401248)the support of China Scholarship Council(2018SLJ022487)。
文摘MXenes are a novel family of two-dimensional(2D)materials that are fast gaining popularity due to their versatile characteristics.The surfaces of these materials are often functionalized by negatively charged terminal groups,such as=O,OH,and F during their synthesis,and it has been hypothesized that regulating the surface terminators enables to control the material characteristics.However,there is still a large gap between computational and experimental investigations regarding comprehending the surface functional groups.Surfaces with mixed terminations are consistently synthesized in experiments,although pure terminated surfaces are predicted by computational research.Here we summarized the nature of chemical bonding in transition metal carbide materials(MXenes)by1H and19F nuclear magnetic resonance(NMR),Raman,X-ray absorption near edge structure(XANES),extended X-ray absorption fine structure(EXAFS),ultraviolet photoelectron spectroscopy(UPS),X-ray photoelectron spectroscopy(XPS)/scanning transmission electron microscopy(STEM),and thermogravimetric analysis-mass spectrometry(TGA-MS)characterizations.Previous literature reveals that=O,–OH,–F,and–Cl are typical MXene surface terminators.However,recent comparative investigations on the valence band intensity distribution in MXenes reveal that the–OH cannot be considered an intrinsic termination species in MXenes.The surface terminals(=O,–OH,–F,and–Cl)of several MXenes,particularly V2CTxand Ti3C2Tx,will be identified and quantified here.We have also discussed different etching approaches for the synthesis of MXene,the dependence of MXene conductivity on MXene terminating groups,and the emission of various gaseous products that evolved during its chemical transformations.This paper provides significance,especially in the field of energy conversion and storage materials,where the intercalation process is crucial.
文摘Two 2-aryl imidazo [2,1-a] isoquinolines were synthesized and tested for pregnancy terminating activities. Both of them are new compounds and their structures were confirmed by IR, (HNMR)-H-1, MS and elemental analysis. They both showed high activities in NIH mice.
文摘In order to clarify the structural requirement of pregnancy-terminating drugs, the quantitative structure-activity relationship (QSAR) of 2-aryl imidazo[2,1-a]isoquinolines was studied on the basis of quantum mechanical calculation and multiple regression analysis. A Good correlation equation was obtained (r2=0.925, q2=0.871). Some new compounds were designed according to the equation. Two of them, compounds 21 and 22, were synthesized and evaluated in NIH mice. The results showed that the difference of activity between 21 (median effective dose ED50=0.943 mg/kg/day) and 22 (ED50=1.099 mg/kg/day) was small and both of them were potent. It is also agreed with the computational results. Compared with L14105 which is the most potent pregnancy-terminating agent, these two compounds possess high activity. The evaluation of the anti-implanting activity showed that they were 100% effective at tested dosage 50.0, 25.0, 12.5 mg/kg/day×3 days in oral administration, which proved the both of them had anti-implanting activity and low first-pass effects.
基金supported by the IITP(Institute for Information&Communications Technology Planning&Evaluation)under the ITRC(Information Technology Research Center)support program(IITP-2025-RS-2024-00438288)grant funded by the Korea government(MSIT)+1 种基金National Research Council of Science&Technology(NST)grant by the MSIT(Aerospace Semiconductor Strategy Research Project No.GTL25051-000)supported by the IC Design Education Center(IDEC),Korea。
文摘This work presents a systematic analysis of proton-induced total ionizing dose(TID)effects in 1.2 k V silicon carbide(SiC)power devices with various edge termination structures.Three edge terminations including ring-assisted junction termination extension(RA-JTE),multiple floating zone JTE(MFZ-JTE),and field limiting rings(FLR)were fabricated and irradiated with45 Me V protons at fluences ranging from 1×10^(12) to 1×10^(14) cm^(-2).Experimental results,supported by TCAD simulations,show that the RA-JTE structure maintained stable breakdown performance with less than 1%variation due to its effective electric field redistribution by multiple P+rings.In contrast,MFZ-JTE and FLR exhibit breakdown voltage shifts of 6.1%and 15.2%,respectively,under the highest fluence.These results demonstrate the superior radiation tolerance of the RA-JTE structure under TID conditions and provide practical design guidance for radiation-hardened Si C power devices in space and other highradiation environments.
基金supported by the National Science Foundation of China(Grant No.41602161,92255302)the National Science and Technology Major Project of China(Project No.2016ZX05033)Sinopec Science and Technology Development Project(Project No.P18089-1,P22085).
文摘The Western Sichuan Foreland Basin(WSFB)in South China,a prolific hydrocarbon province,exhibits complex structural deformation influenced by Triassic salt tectonics.This paper integrates seismic data and well data to elucidate the role of Middle-Lower Triassic evaporite layers in shaping basin structures,focusing on Xinchang Tectonic Zone(XTZ).Salt layers facilitated decoupled deformation between supra-and sub-salt sequences,forming salt pillows and fault-related folds.Three distinct structural trends were identified in XTZ.Key findings reveal that salt thickness variations correlate with deformation styles:thicker salt promoted detachment folding,while thinner salt led to hard-linked fault systems.Sub-salt E-NE trending reverse faults formed horsetail terminations associated with the Pengzhou faults(PzF),deviating from the primary Longmenshan thrust belt(LmsTB)orientation.Structural evolution occurred in three stages:(1)Indosinian salt deposition and foreland basin initiation;(2)Yanshanian eastward propagation of thrust systems with salt-driven detachment folding;(3)Himalayan reactivation overprinting earlier structures with sub-NS trending folds.This work establishes a direct link between salt layers and structural traps,demonstrating how salt acted as a critical detachment layer during multi-stage compression.Results provide insights into the gas exploration of the Late Triassic Xujiahe Formation,emphasizing the importance of salt-influenced deformation in foreland basin systems.
基金Funded by the National Natural Science Foundation of China(No.52278446)。
文摘To explore the best preparation process for terminal blend(TB)composite-modified asphalt and to filter its formulation with excellent performance,this study evaluates the performance of TB composite modified asphalt by physical property index,microscopic morphology,rheological testing,and infrared spectroscopy on multiple scales.The results show that the best preparation process for TB-modified asphalt is stirring at 260℃ for 4 h at 400 rpm,which significantly reduces the modification time of the asphalt.From a physical property viewpoint,the TB composite-modified asphalt sample with 5% styrene-butadiene-styrene(SBS)+1% aromatics+0.1% sulfur exhibits high-comprehensive,high-and low-temperature properties.More-over,its crosslinked mesh structure comprises black rubber particles uniformly interwoven in the middle,which further enhances the performance of the asphalt and results in an excellent performance formulation.In addition,the sample with 5%SBS content has a higher G*value and smaller δ value than that with 3%SBS content,indicating that its high-temperature resistance is improved.The effect of adding 3%SBS content on the viscoelastic ratio is,to some extent,less than that caused by 20% rubber powder.
基金supported by the National Basic Research Program of China under Grant No.2014CB340700the National Science and Technology Major Project of China under Grant No.2012ZX01039-004+3 种基金the National Natural Science Foundation of China under Grant Nos.91118007,11071273,61202131,11401218,cstc2012ggB40004,cstc2013jjys40001SRFDP under Grant No.20130076120010the Open Project of Shanghai Key Laboratory of Trustworthy Computing under Grant No.07dz22304201307West Light Foundation of Chinese Academy of Sciences
文摘This paper investigates the termination problems of multi-path polynomial programs （MPPs） with equational loop guards. To establish sufficient conditions for termination and nontermination simultaneously, the authors propose the notion of strong/weak non-termination which under/over- approximates non-termination. Based on polynomial ideal theory, the authors show that the set of all strong non-terminating inputs （SNTI） and weak non-terminating inputs （WNTI） both correspond to tile real varieties of certain polynomial ideals. Furthermore, the authors prove that the variety of SNTI is computable, and under some sufficient conditions the variety of WNTI is also computable. Then by checking the computed SNTI and WNTI varieties in parallel, termination properties of a consid- ered MPP can be asserted. As a consequence, the authors establish a new framework for termination analysis of MPPs.
基金The project is supported by the National Natural Science Foundation of China.
文摘We define here the concept of head boundedness,head normal form and head confluence of term rewriting systems that allow infinite derivations.Head confluence is weaker than confluence,but suffi- cient to guarantee the correctness of lazy implementations of equational logic programming languages. Then we prove several results.First,if a left-linear system is locally confluent and head-bounded,then it is head-confluent.Second,head-confluent and head-bounded systems have the head Church-Rosser proper- ty.Last,if an orthogonal system is head-terminating,then it is bead-bounded.These results can be ap- plied to generalize equational logic programming languages.
基金supported by the Department of Defense AFIRMⅢW81XWH-20-2-0029 grant subcontractLone Star Paralysis gift,UT POC19-1774-13 grant+1 种基金Neuraptive Therapeutics Inc.26-7724-56 grantNational Institutes of Health R01-NS128086(all to GDB)。
文摘Peripheral nerve injuries result in the rapid degeneration of distal nerve segments and immediate loss of motor and sensory functions;behavioral recovery is typically poor.We used a plasmalemmal fusogen,polyethylene glycol(PEG),to immediately fuse closely apposed open ends of severed proximal and distal axons in rat sciatic nerves.We have previously reported that sciatic nerve axons repaired by PEG-fusion do not undergo Wallerian degeneration,and PEG-fused animals exhibit rapid(within 2–6 weeks)and extensive locomotor recovery.Furthermore,our previous report showed that PEG-fusion of severed sciatic motor axons was non-specific,i.e.,spinal motoneurons in PEG-fused animals were found to project to appropriate as well as inappropriate target muscles.In this study,we examined the consequences of PEG-fusion for sensory axons of the sciatic nerve.Young adult male and female rats(Sprague–Dawley)received either a unilateral single cut or ablation injury to the sciatic nerve and subsequent repair with or without(Negative Control)the application of PEG.Compound action potentials recorded immediately after PEG-fusion repair confirmed conduction across the injury site.The success of PEG-fusion was confirmed through Sciatic Functional Index testing with PEG-fused animals showing improvement in locomotor function beginning at 35 days postoperatively.At 2–42 days postoperatively,we anterogradely labeled sensory afferents from the dorsal aspect of the hindpaw following bilateral intradermal injection of wheat germ agglutinin conjugated horseradish peroxidase.PEG-fusion repair reestablished axonal continuity.Compared to unoperated animals,labeled sensory afferents ipsilateral to the injury in PEG-fused animals were found in the appropriate area of the dorsal horn,as well as inappropriate mediolateral and rostrocaudal areas.Unexpectedly,despite having intact peripheral nerves,similar reorganizations of labeled sensory afferents were also observed contralateral to the injury and repair.This central reorganization may contribute to the improved behavioral recovery seen after PEG-fusion repair,supporting the use of this novel repair methodology over currently available treatments.
基金supported by the National Natural Science Foundation under Grant 62273189the Shandong Province Natural Science Foundation under Grant ZR2021MF005Systems Science Plus Joint Research Program of Qingdao University under Grant XT2024201 of China supporting this research work.
文摘This article investigates the anti-disturbance and stabilization problems for the nonlinear uncertain permanent magnet synchronous motor(PMSM)with stator voltage saturation and unknown load.A smooth switching mechanism is presented to structure the adaptive integral terminal sliding mode control(SMC)strategy.The control design consists of compensation control and nominal control,which improves the rapidity and accuracy of trajectory tracking.The smooth saturation model based on the error function is applied to approximate the voltage saturation phenomenon.Additionally,to deal with the adverse effects of various unknown disturbances,including model parameter uncertainties and unknown external load disturbances,an improved disturbance observer(DO)is proposed.This observer effectively suppresses the fluctuations caused by fixed gain during the starting period of the system.Finally,the experimental results under different conditions show that the proposed strategy has good tracking and disturbance suppression performances.
基金supported by the Artificial Intelligence Innovation and Development Special Fund of Shanghai(No.2019RGZN01041)the National Natural Science Foundation of China(No.92048205).
文摘This paper presents a robust finite-time visual servo control strategy for the tracking problem of omni-directional mobile manipulators(OMMs)subject to mismatched disturbances.First,the nonlinear kinematic model of visual servoing for OMMs with mismatched disturbances is explicitly presented to solve the whole-body inverse kinematic problem.Second,a sliding mode observer augmented with an integral terminal sliding mode controller is proposed to handle these uncertainties and ensure that the system converges to a small region around the equilibrium point.The boundary layer technique is employed to mitigate the chattering phenomenon.Furthermore,a strict finite-time Lyapunov stability analysis is conducted.An experimental comparison between the proposed algorithm and a traditional position-based visual servo controller is carried out,and the results demonstrate the superiority of the proposed control algorithm.
文摘Construction of LNG receiving terminals The scale of receiving terminals is expanding rapidly At the end of 1999,the state approved the Guangdong LNG Pilot Project,which opened the prelude to the construction of LNG receiving terminals.In 2006,China's first LNG receiving terminal,namely Dapeng LNG Receiving Terminal in Shenzhen,Guangdong Province,was put into operation,marking the beginning of the use of overseas natural gas in China.
基金Supported by Project of the Health Bureau of the Logistics and Security Department of the Central Military Commission,No.145BHQ090003076XMilitary Family Planning Special Fund,No.21JSZ18.
文摘BACKGROUND Children with critical acute abdominal conditions often undergo intestinal stoma surgery.AIM To explore the impact of a visual mobile terminal-based extended care model on caregiver competence for children with enterostomies.METHODS One hundred twenty children with enterostomies and their caregivers in a children's hospital in Beijing were divided into a control group and a study group.The control group(60 cases)received traditional telephone follow-up for continuity of care,while the study group(60 cases)used a visualization mobile terminal-based care model.The incidence of stoma-related complications,caregiver burden scale,and competence scores of children with stoma were compared between the two groups.RESULTS The primary caregiver burden score in the study group(37.22±3.17)was significantly lower than that in the control group(80.00±4.47),and the difference was statistically significant(P<0.05).Additionally,the caregiving ability score of the study group(172.08±3.49)was significantly higher than that of the control group(117.55±4.28;P<0.05).The total incidence of complications in the study group(11.7%,7/60)was significantly lower compared to the control group(33.3%,20/60;χ2=8.086,P=0.004).CONCLUSION The visual mobile terminal-based care model reduces caregiver burden,improves home care ability,lowers the incidence of complications and readmission rates,and supports successful second-stage reduction surgery for children with enterostomies.
基金supported by the National Natural Science Foundation of China (No.62275193)。
文摘In this paper,an improved error-rate sliding window decoder is proposed for spatially coupled low-density parity-check(SC-LDPC)codes.For the conventional sliding window decoder,the message retention mechanism causes unreliable messages along the edges of belief propagation(BP)decoding in the current window to be kept for subsequent window decoding.To improve the reliability of the retained messages during the window transition,a reliable termination method is embedded,where the retained messages undergo more reliable parity checks.Additionally,decoding failure is unavoidable and even causes error propagation when the number of errors exceeds the error-correcting capability of the window.To mitigate this problem,a channel value reuse mechanism is designed,where the received channel values are utilized to reinitialize the window.Furthermore,considering the complexity and performance of decoding,a feasible sliding optimized window decoding(SOWD)scheme is introduced.Finally,simulation results confirm the superior performance of the proposed SOWD scheme in both the waterfall and error floor regions.This work has great potential in the applications of wireless optical communication and fiber optic communication.
基金funded by the Ministry of Science and Technology of the People's Republic of China(Grant 2024ZD1001301)the National Natural Science Foundation of China(Grants 42272241,42102254 and 41830213)the Fundamental Research Funds for the Central Universities(Grant JZ2023HGTB0238).
文摘The approximately 3000 km long Tan-Lu fault zone(TLFZ)in East Asia is the longest continental strike-slip fault zone in the world and exemplifies how such a fault zone forms and propagates on a continental scale.Structural and geochronological data from the TLFZ and surrounding regions indicate that the fault zone originated as NE/SW-striking sinistral ductile shear zones along an oblique continental convergence margin during the Triassic indentation collision between the North China Craton and the Yangtze Block.The Triassic fault zone,with a total length of about 720 km between the Dabie and Sulu orogens,exhibited an apparent sinistral offset of approximately 300 km along the TLFZ.The second stage of sinistral movement occurred in the earliest Late Jurassic,reactivating the pre-existing southern segment and propagating northwards to the southern coastline of present-day Bohai Bay,as well as forming a significant portion of the Dunhua-Mishan fault zone.The third stage of sinistral movement,in the earliest Early Cretaceous,was the most intense strike-slip movement of the Mesozoic,leading to the complete linkage of the TLFZ.This stage included further northward propagation of the southern-middle segment,both southward and northward propagation of the Dunhua-Mishan fault zone,as well as the formation of the entire Yilan-Yitong fault zone.The fourth stage,in the earliest Late Cretaceous,involved the reactivation of the entire TLFZ.Following its Triassic origin due to the indentation collision,the subduction of the Paleo-Pacific Plate and the subduction and closure of the Mongol-Okhotsk Ocean were responsible for the multi-stage sinistral movements from the Late Jurassic to the Cretaceous.The evolution of the TLFZ demonstrates that a continental-scale strike-slip fault zone(>1000 km long)forms through multiple stages of propagation and linkage in dynamic settings of plate convergence.
