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Timing theory integrated nursing combined behavior change integrated theory of nursing on primiparous influence 被引量:1
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作者 Yan-Xia He Yang Lv +2 位作者 Ting-Ting Lan Fang Deng Yuan-Yuan Zhang 《World Journal of Clinical Cases》 SCIE 2024年第2期293-301,共9页
BACKGROUND The comprehension and utilization of timing theory and behavior change can offer a more extensive and individualized provision of support and treatment alternatives for primipara.This has the potential to e... BACKGROUND The comprehension and utilization of timing theory and behavior change can offer a more extensive and individualized provision of support and treatment alternatives for primipara.This has the potential to enhance the psychological well-being and overall quality of life for primipara,while also furnishing healthcare providers with efficacious interventions to tackle the psychological and physiological obstacles encountered during the stages of pregnancy and postpartum.AIM To explore the effect of timing theory combined with behavior change on selfefficacy,negative emotions and quality of life in patients with primipara.METHODS A total of 80 primipara cases were selected and admitted to our hospital between August 2020 and May 2022.These cases were divided into two groups,namely the observation group and the control group,with 40 cases in each group.The nursing interventions differed between the two groups,with the control group receiving routine nursing and the observation group receiving integrated nursing based on the timing theory and behavior change.The study aimed to compare the pre-and post-nursing scores of Chinese Perceived Stress Scale(CPSS),Edinburgh Postpartum Depression Scale(EPDS),Self-rating Anxiety Scale(SAS),breast milk knowledge,self-efficacy,and SF-36 quality of life in both groups.RESULTS After nursing,the CPSS,EPDS,and SAS scores of the two groups was significantly lower than that before nursing,and the CPSS,EPDS,and SAS scores of the observation group was significantly lower than that of the control group(P=0.002,P=0.011,and P=0.001 respectively).After nursing,the breastfeeding knowledge mastery,selfefficacy,and SF-36 quality of life scores was significantly higher than that before nursing,and the breastfeeding knowledge mastery(P=0.013),self-efficacy(P=0.008),and SF-36 quality of life(P=0.011)scores of the observation group was significantly higher than that of the control group.CONCLUSION The integration of timing theory and behavior change integrated theory has been found to be an effective approach in alleviating negative mood and stress experienced by primipara individuals,while also enhancing their selfefficacy and overall quality of life.This study focuses on the key concepts of timing theory,behavior change,primipara individuals,negative mood,and quality of life. 展开更多
关键词 timing theory Behavior change PRIMIPARA Bad mood Quality of life
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Different timing for abdominal paracentesis catheter placement and drainage in severe acute pancreatitis complicated by intraabdominal fluid accumulation 被引量:1
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作者 Rui Chen Hua-Qiang Chen +1 位作者 Rui-Die Li Hui-Min Lu 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第1期134-142,共9页
BACKGROUND Non-surgical methods such as percutaneous drainage are crucial for the treatment of patients with severe acute pancreatitis(SAP).However,there is still an ongoing debate regarding the optimal timing for abd... BACKGROUND Non-surgical methods such as percutaneous drainage are crucial for the treatment of patients with severe acute pancreatitis(SAP).However,there is still an ongoing debate regarding the optimal timing for abdominal paracentesis catheter place-ment and drainage.AIM To explore the influence of different timing for abdominal paracentesis catheter placement and drainage in SAP complicated by intra-abdominal fluid accumu-lation.METHODS Using a retrospective approach,184 cases of SAP complicated by intra-abdominal fluid accumulation were enrolled and categorized into three groups based on the timing of catheter placement:group A(catheter placement within 2 d of symptom onset,n=89),group B(catheter placement between days 3 and 5 after symptom onset,n=55),and group C(catheter placement between days 6 and 7 after symptom onset,n=40).The differences in progression rate,mortality rate,and the number of cases with organ dysfunction were compared among the three groups.RESULTS The progression rate of group A was significantly lower than those in groups B and groups C(2.25%vs 21.82%and 32.50%,P<0.05).Further,the proportion of patients with at least one organ dysfunction in group A was significantly lower than those in groups B and groups C(41.57%vs 70.91%and 75.00%,P<0.05).The mortality rates in group A,group B,and group C were similar(P>0.05).At postoperative day 3,the levels of C-reactive protein(55.41±19.32 mg/L vs 82.25±20.41 mg/L and 88.65±19.14 mg/L,P<0.05),procalcitonin(1.36±0.51 ng/mL vs 3.20±0.97 ng/mL and 3.41±0.98 ng/mL,P<0.05),tumor necrosis factor-alpha(15.12±6.63 pg/L vs 22.26±9.96 pg/L and 23.39±9.12 pg/L,P<0.05),interleukin-6(332.14±90.16 ng/L vs 412.20±88.50 ng/L and 420.08±87.65ng/L,P<0.05),interleukin-8(415.54±68.43 ng/L vs 505.80±66.90 ng/L and 510.43±68.23ng/L,P<0.05)and serum amyloid A(270.06±78.49 mg/L vs 344.41±81.96 mg/L and 350.60±80.42 mg/L,P<0.05)were significantly lower in group A compared to those in groups B and group C.The length of hospital stay in group A was significantly lower than those in groups B and group C(24.50±4.16 d vs 35.54±6.62 d and 38.89±7.10 d,P<0.05).The hospitalization expenses in group A were also significantly lower than those in groups B and groups C[2.70(1.20,3.55)ten-thousand-yuan vs 5.50(2.98,7.12)ten-thousand-yuan and 6.00(3.10,8.05)ten-thousand-yuan,P<0.05).The incidence of complications in group A was markedly lower than that in group C(5.62%vs 25.00%,P<0.05),and similar to group B(P>0.05).CONCLUSION Percutaneous catheter drainage for the treatment of SAP complicated by intra-abdominal fluid accumulation is most effective when performed within 2 d of onset. 展开更多
关键词 Abdominal paracentesis catheter drainage timing Severe acute pancreatitis Intra-abdominal fluid Application value
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Evolution mechanism and treatment timing of penetrating fissures
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作者 ZHANG Yanjun YAN Yueguan +1 位作者 ZHU Yuanhao DAI Huayang 《Journal of Mountain Science》 SCIE CSCD 2024年第10期3453-3473,共21页
The Inner Mongolia mining area in western China are characterized by the development of numerous penetrating fissures,resulting in severe land damage.It is significant to reveal the underlying evolution mechanism and ... The Inner Mongolia mining area in western China are characterized by the development of numerous penetrating fissures,resulting in severe land damage.It is significant to reveal the underlying evolution mechanism and identify treatment timing for restoring the ecological environment.The Guanbanwusu mining subsidence area in Inner Mongolia,China was selected as the research case for this study.The evolution mechanism of different penetrating fissures was revealed by field measurement,physical simulation and theoretical analysis.The treatment timing prediction model for the mining subsidence area was established based on the enhanced Weibull time function.The results show that the ground fissures are mainly step-type and collapse-type fissures.The breaking form of overlying strata determines their vertical opening and horizontal dislocation.The high mining intensity in the western mining area results in a shortened period of dynamic fissure expansion and reduced closure degree.The damage extent of the overlying strata exhibits zoning characteristics both vertically and horizontally.The relative standard deviation of the prediction model is only 3.7%.Concurrently,the prediction model is employed to determine the optimal timing for treatment in the study area,estimated to be 259 days.Subsequently,once this threshold is reached,the study area undergoes treatment and restoration of its e cological environment.This study addresses the knowledge gap in this field by highlighting the interconnectedness between rock strata structure and evolution mechanism of penetrating fissures,thereby providing a method for determining the treatment timing in mining subsidence areas. 展开更多
关键词 Mining subsidence Ecological restoration FISSURES Evolution mechanism Prediction model Treatment timing
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Optimization method of refracturing timing for old shale gas wells
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作者 WANG Qiang ZHAO Jinzhou +2 位作者 HU Yongquan LI Yongming WANG Yufeng 《Petroleum Exploration and Development》 SCIE 2024年第1期213-222,共10页
Based on the elastic theory of porous media,embedded discrete fracture model and finite volume method,and considering the micro-seepage mechanism of shale gas,a fully coupled seepage-geomechanical model suitable for f... Based on the elastic theory of porous media,embedded discrete fracture model and finite volume method,and considering the micro-seepage mechanism of shale gas,a fully coupled seepage-geomechanical model suitable for fractured shale gas reservoirs is established,the optimization method of refracturing timing is proposed,and the influencing factors of refracturing timing are analyzed based on the data from shale gas well in Fuling of Sichuan Basin.The results show that due to the depletion of formation pressure,the percentage of the maximum horizontal principal stress reversal area in the total area increases and then decreases with time.The closer the area is to the hydraulic fracture,the shorter the time for the peak of the stress reversal area percentage curve to appear,and the shorter the time for the final zero return(to the initial state).The optimum time of refracturing is affected by matrix permeability,initial stress difference and natural fracture approach angle.The larger the matrix permeability and initial stress difference is,the shorter the time for stress reversal area percentage curve to reach peak and return to the initial state,and the earlier the time to take refracturing measures.The larger the natural fracture approach angle is,the more difficult it is for stress reversal to occur near the fracture,and the earlier the optimum refracturing time is.The more likely the stress reversal occurs at the far end of the artificial fracture,the later the optimal time of refracturing is.Reservoirs with low matrix permeability have a rapid decrease in single well productivity.To ensure economic efficiency,measures such as shut-in or gas injection can be taken to restore the stress,and refracturing can be implemented in advance. 展开更多
关键词 shale gas well fully coupled seepage-geomechanical model REFRACTURING timing optimization influencing factor
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Fracturing timing of Jurassic reservoirs in the Dibei-Tuziluoke gas field,Kuqa foreland basin:Evidence from petrography,fluid inclusions,and clumped isotopes
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作者 Guoding Yu Wenfang Yuan +6 位作者 Kelai Xi Yin Liu Shuai Wang Zhenping Xu Jing Yuan Lu Zhou Keyu Liu 《Energy Geoscience》 EI 2024年第2期129-140,共12页
Determining the timing of fracturing is crucial for understanding reservoir evolution and hydrocarbon accumulation in foreland basins.Using fracturing data from cores,borehole images,and outcrops,combined with the clu... Determining the timing of fracturing is crucial for understanding reservoir evolution and hydrocarbon accumulation in foreland basins.Using fracturing data from cores,borehole images,and outcrops,combined with the clumped isotope(D47)and fluid inclusion analyses of carbonate minerals filled in pores and fractures,this study ascertained the fracturing timing of the Jurassic reservoirs in the Dibei-Tuziluoke Gas Field,Kuqa Foreland Basin.Data from outcrops and borehole images show two dominant fracture sets in the study area:W-E and NE-SW striking fractures.Some W-E striking fractures are carbonate-filled,while NE-SW striking fractures lack mineral fillings.Bitumen veins,not easy to be identified in borehole images,are prevalent in cores.The petrographic analysis reveals that these bitumen veins formed before the calcite cementation in pores and display high viscosity and low maturity.Homogenization temperatures(T_(h))from primary fluid inclusion assemblages in two representative calcite vein samples were notably lower than T_(△47) values from corresponding samples.This suggests the △_(47) signature underwent alteration due to partial reordering during burial.Thus,△_(47)-derived temperatures(apparent temperatures)may not faithfully represent the mineral precipitation temperatures.When plotting these apparent temperatures vs.the burial history,only the possible latest ages of fracturing emerged.These ages were further refined by considering petroleum charging,tectonic evolution,and stress orientation.Bitumen-filled fractures likely resulted from the Late Cretaceous uplift,marking the migration of low-maturity hydrocarbons in the study area.Carbonate-filled E-W striking fractures emerged during the late Miocene(~13-6.5 Ma)alongside fold development.NE-striking fractures that crosscut W-E ones possibly formed recently due to stress reorientation. 展开更多
关键词 Fracture Borehole imaging Bitumen vein Clumped isotope Fracturing timing
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Clinical efficacy and safety of kyphoplasty for the treatment of osteoporotic vertebral compression fractures at different surgical timings based on the theory of“dynamic-static integration”
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作者 Zunwang Li Jiang Chen +3 位作者 Dekui Li Jiayu Yang Jiaqi Qin Yuqing Guan 《Journal of Traditional Chinese Medical Sciences》 CAS 2024年第1期86-92,共7页
Objective:To investigate the clinical efficacy and safety of percutaneous kyphoplasty at different surgical timings in the treatment of osteoporotic vertebral compression fracture(OVCF)based on the theory of“dynamic-... Objective:To investigate the clinical efficacy and safety of percutaneous kyphoplasty at different surgical timings in the treatment of osteoporotic vertebral compression fracture(OVCF)based on the theory of“dynamic-static integration”.Methods:Patients with OVCF who underwent percutaneous kyphoplasty in our hospital were selected and divided into Groups A,B,and C for those undergoing surgery within 7,7—21,and>21 days of fracture occurrence.The variations in the amount of bone cement injected,pre-and post-operative pain levels,functional activity,deformity correction of the injured vertebrae,bone cement leakage,and vertebral body height loss were compared among the three groups.Results:Regarding pain relief and functional activity,the postoperative Visual Analog Scale and Oswestry Disability Index scores of the three groups significantly improved.Furthermore,the deformities of the injured vertebrae in the three groups were significantly corrected,with Groups A and B exhibiting superior correction compared to Group C.Moreover,the bone cement leakage rates in groups A and C were higher than that in Group B.At the 3-month follow-up,the loss of vertebral height in Group C was significantly higher than those in groups A and B.Conclusion:Kyphoplasty is effective for OVCF treatment.Early surgery can effectively restore the vertebral height of the injured vertebra,reduce kyphosis,and reduce height loss of the injured vertebra after surgery;nevertheless,treatment within 1—3 weeks of the fracture can reduce the occurrence of bone cement leakage,making the surgery safer.Therefore,surgical treatment within 1—3 weeks of fracture is safer and can achieve satisfactory therapeutic effects.From the perspective of traditional Chinese medicine,PKP surgery can transform the fracture end from a micromotion state to a fixed state,which fully embodies the theory of“dynamic-static integration”. 展开更多
关键词 KYPHOPLASTY Operation timing Bone cement leakage Lost height of injured vertebra
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Timing impact on the initiation of pirfenidone therapy on idiopathic pulmonary fibrosis disease progression
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作者 Basma M E Mohamed Mohamed E A Abdelrahim 《World Journal of Clinical Cases》 SCIE 2024年第32期6538-6542,共5页
In this editorial,we comment on the article by Lei et al,with a specific focus on the timing of the initiation of the antifibrotic agent pirfenidone(PFD)in the management of idiopathic pulmonary fibrosis(IPF)and its i... In this editorial,we comment on the article by Lei et al,with a specific focus on the timing of the initiation of the antifibrotic agent pirfenidone(PFD)in the management of idiopathic pulmonary fibrosis(IPF)and its impact on lung function of IPF patients.PFD is an antifibrotic agent that is widely used in the management of IPF in both early and advanced stages.It inhibits various pathways and has antifibrotic,anti-inflammatory,and antioxidant properties.Despite dosage lowering,PFD slowed IPF progression and maintained functional capacity.The 6-min walk distance test indicated that patients tolerated adverse events well,and PFD significantly reduced the incidence of progression episodes and death.Even when a single disease-progression event occurred,continuing PFD treatment had benefits. 展开更多
关键词 Idiopathic pulmonary fibrosis Pirfenidone Pirfenidone anti-inflammatory mechanism Pirfenidone antifibrotic activity timing impact
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Optimal timing for plastic surgical procedures for common congenital anomalies:A review
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作者 Aakanksha Goel Arun Goel 《World Journal of Clinical Pediatrics》 2024年第2期38-61,共24页
Apart from listening to the cry of a healthy newborn,it is the declaration by the attending paediatrician in the labour room that the child is normal which brings utmost joy to parents.The global incidence of children... Apart from listening to the cry of a healthy newborn,it is the declaration by the attending paediatrician in the labour room that the child is normal which brings utmost joy to parents.The global incidence of children born with congenital anomalies has been reported to be 3%-6%with more than 90%of these occurring in low-and middle-income group countries.The exact percentages/total numbers of children requiring surgical treatment cannot be estimated for several reasons.These children are operated under several surgical disciplines,viz,paediatric-,plastic reconstructive,neuro-,cardiothoracic-,orthopaedic surgery etc.These conditions may be life-threatening,e.g.,trachea-oesophageal fistula,critical pulmonary stenosis,etc.and require immediate surgical intervention.Some,e.g.,hydrocephalus,may need intervention as soon as the patient is fit for surgery.Some,e.g.,patent ductus arteriosus need‘wait and watch’policy up to a certain age in the hope of spontaneous recovery.Another extremely important category is that of patients where the operative intervention is done based on their age.Almost all the congenital anomalies coming under care of a plastic surgeon are operated as elective surgery(many as multiple stages of correction)at appropriate ages.There are advantages and disadvantages of intervention at different ages.In this article,we present a review of optimal timings,along with reasoning,for surgery of many of the common congenital anomalies which are treated by plastic surgeons.Obstetricians,paediatricians and general practitioners/family physicians,who most often are the first ones to come across such children,must know to guide the parents appropriately and convincingly impress upon the them as to why their child should not be operated immediately and also the consequences of too soon or too late. 展开更多
关键词 Plastic surgery Congenital anomalies Pediatric plastic surgery Facial cleft MICROTIA Vascular anomalies SYNDACTYLY HYPOSPADIAS Optimal timing Pediatric surgery
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The Timing of Primary Neurosurgical Repair and Wound-Site Infection in Children with Myelomeningocele
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作者 Joseph O. Obande Paul T. Bitrus Elizabeth I. Obande 《Open Journal of Modern Neurosurgery》 2024年第2期137-148,共12页
Background: The optimal time to closure of a newborn with a myelomeningocele has been the focus of a number of evaluations. The Timing of primary surgery has received significant attention due to its relationship to r... Background: The optimal time to closure of a newborn with a myelomeningocele has been the focus of a number of evaluations. The Timing of primary surgery has received significant attention due to its relationship to repair-site infection that can lead to increased morbidity and prolonged hospital stays. It is on this basis that recommendations have utilized 48 - 72 hours post birth as ideal time of closure. This is not only prevent infection at the site but also prevent ventriculitis and neural structure damage. We therefore, hypothesized an increase in wound infection rates in those patients with delays in myelomeningocele repair. Methods: We retrospectively reviewed the records of 103 children with myelomeningocele treated between 2016 and 2023. At discharge the patients were followed up at the post-operative clinic visit 2 weeks later. Children were assigned to 1 of 2 groups, those who underwent primary neurosurgical repair within 72 hours of delivery (Group 1) and those undergoing repair after 72 hours (Group 2). We compared the infection rates. Results: 103 children who underwent myelomeningocele repair were identified, with a median time from birth to treatment of 1 day. Eight (7.8 %) patients were noted to have post-repair surgical site complications. There was no significant difference in rates of infection between Group 1 and Group 2 repair times. The presence of infection was associated increased length of stay when compared to neonates without infection. Conclusion: In children with myelomeningocele, the timing of primary neurosurgical repair appears not to have a significant impact on surgical site infection. Closure of the spinal lesion within the first 72 hours of life may be more favorable for neural damage prevention. These results suggest that early myelomeningocele repair may not impart significantly on the rate of wound-site infection. 展开更多
关键词 Spina Bifida Surgical timing Excision and Repair Surgical Site Infection MYELOMENINGOCELE
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Timing of Continuous Renal Replacement Therapy Initiation in Sepsis-Associated Acute Kidney Injury: A Comprehensive Review and Future Directions
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作者 Zhengshuang Liu Chuanren Zhuang Xuehuan Wen 《Journal of Clinical and Nursing Research》 2024年第8期21-30,共10页
This review examines the application of continuous renal replacement therapy(CRRT)in patients with sepsis-associated acute kidney injury(S-AKI),with a particular focus on the timing of CRRT initiation.This review addr... This review examines the application of continuous renal replacement therapy(CRRT)in patients with sepsis-associated acute kidney injury(S-AKI),with a particular focus on the timing of CRRT initiation.This review addresses the controversy surrounding initiation timing and proposes future research directions.Through a systematic review of recent literature on CRRT for S-AKI,working principles,therapeutic mechanisms,initiation timing of CRRT,and related meta-analyses were summarized.Current studies indicate that the optimal timing for CRRT initiation in S-AKI patients remains inconclusive,with ongoing debate regarding whether early initiation significantly improves patient survival and renal function.This lack of consensus reflects the heterogeneity of the S-AKI patient population and the limitations of existing research methodologies.Future studies should focus on advancing the application of precision medicine in S-AKI and developing individualized treatment strategies by integrating multidimensional information to optimize CRRT utilization and improve patient outcomes. 展开更多
关键词 SEPSIS Sepsis-related acute kidney injury Continuous renal replacement therapy(CRRT) timing of initiation
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Research into polymer injection timing for Bohai heavy oil reservoirs 被引量:4
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作者 Lei-Ting Shi Shi-Jie Zhu +4 位作者 Jian Zhang Song-Xia Wang Xin-Sheng Xue Wei Zhou Zhong-Bin Ye 《Petroleum Science》 SCIE CAS CSCD 2015年第1期129-134,共6页
Polymer flooding has been proven to effectively improve oil recovery in the Bohai Oil Field. However, due to high oil viscosity and significant formation heterogeneity, it is necessary to further improve the displacem... Polymer flooding has been proven to effectively improve oil recovery in the Bohai Oil Field. However, due to high oil viscosity and significant formation heterogeneity, it is necessary to further improve the displacement effectiveness of polymer flooding in heavy oil reservoirs in the service life of offshore platforms. In this paper, the effects of the water/oil mobility ratio in heavy oil reservoirs and the dimensionless oil productivity index on polymer flooding effectiveness were studied utilizing rel- ative permeability curves. The results showed that when the water saturation was less than the value, where the water/oil mobility ratio was equal to 1, polymer flooding could effectively control the increase of fractional water flow, which meant that the upper limit of water/oil ratio suitable for polymer flooding should be the value when the water/oil mobility ratio was equal to 1. Mean while, by injecting a certain volume of water to create water channels in the reservoir, the polymer flooding would be the most effective in improving sweep efficiency, and lower the fractional flow of water to the value corresponding to △Jmax. Considering the service life of the platform and the polymer mobility control capacity, the best polymer injection timing for heavy oil reservoirs was optimized. It has been tested for reservoirs with crude oil viscosity of 123 and 70 mPa s, the optimum polymer flooding effec- tiveness could be obtained when the polymer floods were initiated at the time when the fractional flow of water were 10 % and 25 %, respectively. The injection timing range for polymer flooding was also theoretically analyzed for the Bohai Oil Field utilizing which provided methods for effectiveness. relative permeability curves, improving polymer flooding 展开更多
关键词 Heavy oil reservoir Mobility ratio Polymer injection timing Injection timing range timing optimization
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Synthesis Scheme for Low Power Designs Under Timing Constraints 被引量:5
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作者 王玲 温东新 +1 位作者 杨孝宗 蒋颖涛 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2005年第2期287-293,共7页
To minimize the power consumption with resources operating at multiple voltages a time-constrained algorithm is presented.The input to the scheme is an unscheduled data flow graph (DFG),and timing or resource constrai... To minimize the power consumption with resources operating at multiple voltages a time-constrained algorithm is presented.The input to the scheme is an unscheduled data flow graph (DFG),and timing or resource constraints.Partitioning is considered with scheduling in the proposed algorithm as multiple voltage design can lead to an increase in interconnection complexity at layout level.That is,in the proposed algorithm power consumption is first reduced by the scheduling step,and then the partitioning step takes over to decrease the interconnection complexity.The time-constrained algorithm has time complexity of O(n 2),where n is the number of nodes in the DFG.Experiments with a number of DSP benchmarks show that the proposed algorithm achieves the power reduction under timing constraints by an average of 46 5%. 展开更多
关键词 low power multiple supply voltages partitioning timing constraints SCHEDULING
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Method for pedestrian signal timing at signalized intersections 被引量:3
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作者 王京元 王炜 《Journal of Southeast University(English Edition)》 EI CAS 2006年第4期564-569,共6页
The pedestrian timing at signalized intersections is studied aiming at the problems of the inconsistency of the vehicular and pedestrian timing requirements and the insufficiency of pedestrian clearance. Based on the ... The pedestrian timing at signalized intersections is studied aiming at the problems of the inconsistency of the vehicular and pedestrian timing requirements and the insufficiency of pedestrian clearance. Based on the formulae of WALK and flashing DON'T WALK (FDW) in the highway capacity manual (HCM), the relationship between pedestrian signal indications and vehicular signal indications is discussed using the theory of traffic flow. Then, methods of pedestrian timing for different cases are established, particularly the methods of the pedestrian green adjustment. Ways of pedestrian crossing are analyzed for roadways with different forms and widths of the median island. The sampling values of calculation parameters are studied, and the recommended formulae of pedestrian timing for different conditions are presented. 展开更多
关键词 signalized intersection pedestrian signal timing WALK indication flashing DON'T WALK indication
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The Timing System of the Neutral Beam Injector on EAST 被引量:1
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作者 盛鹏 胡纯栋 +6 位作者 赵远哲 崔庆龙 张小丹 吴德云 张睿 林宇莲 NBI team 《Plasma Science and Technology》 SCIE EI CAS CSCD 2015年第5期425-429,共5页
In order to synchronize the elements of the EAST Neutral Beam Injector (NBI) spatially located in several places, a distributed Timing System (TS) is developed in this paper. The timing system provides a clock ref... In order to synchronize the elements of the EAST Neutral Beam Injector (NBI) spatially located in several places, a distributed Timing System (TS) is developed in this paper. The timing system provides a clock reference for synchronization and an interlock protection of the EAST NBI system. It sends timing signals to field devices, controls the pulse widths of the timing sequences, and provides a sampling clock for the Data Acquisition System (DAS). The timing system also generates analog waveforms to control power supplies and gas supplies according to the operator's configuration. The timing system is developed on a PXI (PCI eXtensions for Instrumentation) platform consisting of a LabVIEW workstation and a timing control terminal. The timing control terminal consists of a timing node and several control interface crates. Two timing nodes are configured in one beam line. Each node is responsible for the timing sequence, analog generation and feedback control for one ion source. The architecture and implementation of the timing system are presented in this paper. 展开更多
关键词 timing system neutral beam injector EAST timing sequence
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Path-Based Timing Optimization by Buffer Insertion with Accurate Delay Model
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作者 张轶谦 周强 +1 位作者 洪先龙 蔡懿慈 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2004年第5期520-525,共6页
An algorithm of path based timing optimization by buffer insertion is presented.The algorithm adopts a high order model to estimate interconnect delay and a nonlinear delay model based on look up table for gate dela... An algorithm of path based timing optimization by buffer insertion is presented.The algorithm adopts a high order model to estimate interconnect delay and a nonlinear delay model based on look up table for gate delay estimation.And heuristic method of buffer insertion is presented to reduce delay.The algorithm is tested by industral circuit case.Experimental results show that the algorithm can optimize the timing of circuit efficiently and the timing constraint is satisfied. 展开更多
关键词 buffer insertion timing optimization interconnect planning routing algorithm
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Incremental Placement Algorithm for Timing and Routability Optimization
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作者 李卓远 吴为民 洪先龙 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2004年第2期158-164,共7页
A new approach of incremental placement approach is described.The obtained timing information drives an efficient net-based placement technique,which dynamically adapts the net weights during successive placement step... A new approach of incremental placement approach is described.The obtained timing information drives an efficient net-based placement technique,which dynamically adapts the net weights during successive placement steps.Several methods to combine timing optimization and congestion reducing together are proposed.Cells on critical paths are replaced according to timing and congestion constraints.Experimental results show that our approach can efficiently reduce cycle time and enhance route ability.The max path delay is reduced by 10% on an average afterincremental placement on wirelength-optimized circuits.And it achieves the same quality with a high speed up compared to timing driven detailed placement algorithm. 展开更多
关键词 timing CONGESTION incremental placement
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基于AVL EXCITE Timing Drive的发动机配气正时分析前处理自动化开发 被引量:1
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作者 余伟 余彪 曹江怀 《机电信息》 2018年第30期136-137,共2页
基于AVL EXCITE Timing Drive对发动机配气正时系统进行自动化二次开发,对各种不同布置的系统通过编写脚本程序建立对应的标准模型模板,运行脚本即可自动完成模型搭建与数据输入,无需逐个零件建模与数据赋予,显著减少了人工操作,大幅缩... 基于AVL EXCITE Timing Drive对发动机配气正时系统进行自动化二次开发,对各种不同布置的系统通过编写脚本程序建立对应的标准模型模板,运行脚本即可自动完成模型搭建与数据输入,无需逐个零件建模与数据赋予,显著减少了人工操作,大幅缩短了分析周期。 展开更多
关键词 配气正时系统 AVL EXCITE timing DRIVE 仿真 自动化 二次开发
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Timing Error Aware Register Allocation in TS
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作者 Sheng Xiao Jing He +2 位作者 Xi Yang Heng Zhou Yujie Yuan 《Computer Systems Science & Engineering》 SCIE EI 2022年第1期273-286,共14页
Timing speculative(TS)architecture is promising for improving the energy efficiency of microprocessors.Error recovery units,designed for tolerating occasional timing errors,have been used to support a wider range of v... Timing speculative(TS)architecture is promising for improving the energy efficiency of microprocessors.Error recovery units,designed for tolerating occasional timing errors,have been used to support a wider range of voltage scaling,therefore to achieve a better energy efficiency.More specifically,the timing error rate,influenced mainly by data forwarding,is the bottleneck for voltage down-scaling in TS processors.In this paper,a new Timing Error Aware Register Allocation method is proposed.First,we designed the Dependency aware Interference Graph(DIG)construction to get the information of Read after Write(RAW)in programs.To build the construction,we get the disassemble code as input and suppose that there are unlimited registers,the same way as so-called virtual registers in many compilers.Then we change the disassemble codes to the SSA form for each basic block to make sure the registers are defined only once.Based on the DIG construction,registers were real-located to eliminate the timing error,by loosening the RAW dependencies.We con-struct the DIG for each function of the program and sort the edge of DIG by an increasing weight order.Since a smaller weighted-edge value means that its owner nodes have more frequent access in instruction flows,we expect it in different registers with no read-write dependency.At the same time,we make sure that there are no additional new spill codes emerging in our algorithm to minimize the rate of spill code.A high rate of spill code will not only decrease the performance of the system but also increase the unexpected read-write dependency.Next,we reallocate the reg-isters by weight order in turn to loosen the RAW dependencies.Furthermore,we use the NOP operation to pad the instructions with a minimal distance value of 2.Experiment results showed that the average distance of RAW dependencies was increased by over 20%. 展开更多
关键词 timing error timing speculative architecture register allocation energy efficiency
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Effect of Hydrogen Addition on Methane HCCI Engine Ignition Timing and Emissions Using a Multi-zone Model 被引量:1
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作者 汪子涵 汪春梅 +2 位作者 唐华欣 左承基 徐宏明 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2009年第3期290-296,340,共8页
Ignition timing control is of great importance in homogeneous charge compression ignition engines. The effect of hydrogen addition on methane combustion was investigated using a CHEMKIN multi-zone model. Results show ... Ignition timing control is of great importance in homogeneous charge compression ignition engines. The effect of hydrogen addition on methane combustion was investigated using a CHEMKIN multi-zone model. Results show that hydrogen addition advances ignition tim- ing and enhances peak pressure and temperature. A brief analysis of chemical kinetics of methane blending hydrogen is also performed in order to investigate the scope of its appli- cation, and the analysis suggests that OH radical plays an important role in the oxidation. Hydrogen addition increases NOx while decreasing HC and CO emissions. Exhaust gas recir- culation (EGR) also advances ignition timing; however, its effects on emissions are generally the opposite. By adjusting the hydrogen addition and EGR rate, the ignition timing can be regulated with a low emission level. Investigation into zones suggests that NOx is mostly formed in core zones while HC and CO mostly originate in the crevice and the quench layer. 展开更多
关键词 Homogeneous charge compression ignition Multi-zone model METHANE Hy- drogen Ignition timing EMISSION
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Timing Belts Dynamics Model Approach
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作者 Domek Grzegorz 《Journal of Mechanics Engineering and Automation》 2012年第8期495-498,共4页
Design of composites and usage of new polymer materials allows for improvement of constructional properties of belts. Different applications: transmission, conveying or controlling have different meshing in gear. The... Design of composites and usage of new polymer materials allows for improvement of constructional properties of belts. Different applications: transmission, conveying or controlling have different meshing in gear. The work presents meshing model between timing belt and pulley and constructional features of transmission timing belts depending on materials used for their production. While designing timing belt, much attention should be paid to selection of materials, which has significant influence on mechanical properties of belts. This paper attempts to identify the model material and the nature of cooperation of timing belt-pulley; this is basic knowledge for the development of timing belt gear. 展开更多
关键词 timing belts timing pulleys synchronous drives polymer materials in belts.
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