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Feedback linearization and equivalent-disturbance compensation control strategy for piezoelectric stage
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作者 Tao Huang Yingbin Wang +3 位作者 Zhihong Luo Huajun Cao Guibao Tao Mingxiang Ling 《Nanotechnology and Precision Engineering》 EI CAS CSCD 2024年第2期49-59,共11页
Piezoelectric stages use piezoelectric actuators and flexure hinges as driving and amplifying mechanisms,respectively.These systems have high positioning accuracy and high-frequency responses,and they are widely used ... Piezoelectric stages use piezoelectric actuators and flexure hinges as driving and amplifying mechanisms,respectively.These systems have high positioning accuracy and high-frequency responses,and they are widely used in various precision/ultra-precision positioning fields.However,the main challenge with these devices is the inherent hysteresis nonlinearity of piezoelectric actuators,which seriously affects the tracking accuracy of a piezoelectric stage.Inspired by this challenge,in this work,we developed a Hammerstein model to describe the hysteresis nonlinearity of a piezoelectric stage.In particular,in our proposed scheme,a feedback-linearization algorithm is used to eliminate the static hysteresis nonlinearity.In addition,a composite controller based on equivalent-disturbance compensation was designed to counteract model uncertainties and external disturbances.An analysis of the stability of a closed-loop system based on this feedback-linearization algorithm and composite controller was performed,and this was followed by extensive comparative experiments using a piezoelectric stage developed in the laboratory.The experimental results confirmed that the feedback-linearization algorithm and the composite controller offer improved linearization and trajectory-tracking performance. 展开更多
关键词 Piezoelectric stage Hysteresis nonlinearity Feedback linearization Equivalent-disturbance compensation
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An Elite-Class Teaching-Learning-Based Optimization for Reentrant Hybrid Flow Shop Scheduling with Bottleneck Stage
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作者 Deming Lei Surui Duan +1 位作者 Mingbo Li Jing Wang 《Computers, Materials & Continua》 SCIE EI 2024年第4期47-63,共17页
Bottleneck stage and reentrance often exist in real-life manufacturing processes;however,the previous research rarely addresses these two processing conditions in a scheduling problem.In this study,a reentrant hybrid ... Bottleneck stage and reentrance often exist in real-life manufacturing processes;however,the previous research rarely addresses these two processing conditions in a scheduling problem.In this study,a reentrant hybrid flow shop scheduling problem(RHFSP)with a bottleneck stage is considered,and an elite-class teaching-learning-based optimization(ETLBO)algorithm is proposed to minimize maximum completion time.To produce high-quality solutions,teachers are divided into formal ones and substitute ones,and multiple classes are formed.The teacher phase is composed of teacher competition and teacher teaching.The learner phase is replaced with a reinforcement search of the elite class.Adaptive adjustment on teachers and classes is established based on class quality,which is determined by the number of elite solutions in class.Numerous experimental results demonstrate the effectiveness of new strategies,and ETLBO has a significant advantage in solving the considered RHFSP. 展开更多
关键词 Hybrid flow shop scheduling REENTRANT bottleneck stage teaching-learning-based optimization
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Dry eye rate and its relationship with disease stage in patients with primary hypertension:a cross-sectional study in Vietnam
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作者 Tran Tat Thang Pham Hong Phuong +7 位作者 Nguyen Sa Huynh Nguyen Trung Kien NguyenDuy Toan Nguyen Thi Thu Ha Le Ha Khoa Nguyen Huu Dung Thai Doan Thang Le Viet Thang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第4期653-658,共6页
AIM:To determine the dry eye(DE)rate and its relationship with disease stage in patients with primary hypertension.METHODS:A cross-sectional study included 432 patients with primary hypertension(with an equal number o... AIM:To determine the dry eye(DE)rate and its relationship with disease stage in patients with primary hypertension.METHODS:A cross-sectional study included 432 patients with primary hypertension(with an equal number of patients in each group:144 in stage Ⅰ,Ⅱ,and Ⅲ hypertension)and 144 healthy subjects as a control group.The Ocular Surface Disease Index(OSDI)and Schirmer Ⅰ test without anesthetics were conducted on all 576 subjects.Subjects with OSDI scores<13 and Schirmer Ⅰ values equal to or under 10 mm were diagnosed with DE.RESULTS:The ratio of DE in hypertension patients was higher than in the control group(41.7%versus 18.8%;P<0.001).The proportion of patients with DE increased gradually according to the hypertension stage:27.1% in stage Ⅰ,40.3% in stage Ⅱ,and 57.6% in stage Ⅲ,P<0.001.Age,duration of hypertension,plasma urea,creatinine,and high-sensitivity C-reactive protein(CRP-hs)levels in hypertension patients with DE were higher than those without DE,P<0.001.Advanced age,a long duration of hypertension,diabetes mellitus,elevated plasma creatinine,and CRP-hs levels were independent factors associated with DE in primary hypertension patients,P<0.001.CONCLUSION:DE is a common disorder associated with advanced age,a long duration of hypertension,diabetes mellitus,elevated plasma CRP-hs,and creatinine levels in patients with primary hypertension. 展开更多
关键词 primary hypertension dry eye stage of hypertension plasma creatinine
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CmMYB3-like negatively regulates anthocyanin biosynthesis and flower color formation during the post-flowering stage in Chrysanthemum morifolium
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作者 Lijie Zhou Shenhui Liu +6 位作者 Yiguang Wang Yuxi Wang Aiping Song Jiafu Jiang Sumei Chen Zhiyong Guan Fadi Chen 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第1期194-204,共11页
Color fading caused by a decrease in anthocyanin accumulation during the post-flowering stage significantly affects postharvest quality of chrysanthemum.However,the underlying mechanism by which anthocyanin accumulati... Color fading caused by a decrease in anthocyanin accumulation during the post-flowering stage significantly affects postharvest quality of chrysanthemum.However,the underlying mechanism by which anthocyanin accumulation decreases during the post-flowering stage still unclear,which greatly restricts design of molecular breeding in chrysanthemum.Here,a chrysanthemum SG7 R2R3 MYB transcription factor(TF),CmMYB3-like,was identified to have a function in regulating anthocyanin biosynthesis during the post-flowering stage.Quantitative real time PCR(qRT-PCR)assays showed that the expression of CmMYB3-like was gradually downregulated when anthocyanin content increased during the flowering stage and was significantly upregulated during the post-flowering stage.Genetic transformation of chrysanthemum and dual-luciferase assays in N.benthamiana leaves showed that CmMYB3-like suppressed anthocyanin accumulation by inhibiting the transcription of CmCHS and CmANS directly and that of CmF3H indirectly.However,overexpression or suppression of CmMYB3-like did not affect the biosynthesis of flavones or flavonols.Genetic transformation of chrysanthemum revealed that the overexpression of CmMYB3-like inhibited anthocyanin accumulation,but its suppression prevented the decrease in anthocyanin accumulation during the post-flowering stage.Our results revealed a crucial role of CmMYB3-like in regulating the color of petals during the post-flowering stage and provided a target gene for molecular design breeding to improve the postharvest quality of chrysanthemum. 展开更多
关键词 Post-flowering stage Color fading Anthocyanins CmMYB3-like CHRYSANTHEMUM Molecular breeding
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Single-cell profiling of the pig cecum at various developmental stages
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作者 Yan-Yuan Xiao Qing Zhang +9 位作者 Fei Huang Lin Rao Tian-Xiong Yao Si-Yu Yang Lei Xie Xiao-Xiao Zou Li-Ping Cai Jia-Wen Yang Bin Yang Lu-Sheng Huang 《Zoological Research》 SCIE CSCD 2024年第1期55-68,共14页
The gastrointestinal tract is essential for food digestion,nutrient absorption,waste elimination,and microbial defense.Single-cell transcriptome profiling of the intestinal tract has greatly enriched our understanding... The gastrointestinal tract is essential for food digestion,nutrient absorption,waste elimination,and microbial defense.Single-cell transcriptome profiling of the intestinal tract has greatly enriched our understanding of cellular diversity,functional heterogeneity,and their importance in intestinal tract development and disease.Although such profiling has been extensively conducted in humans and mice,the single-cell gene expression landscape of the pig cecum remains unexplored.Here,single-cell RNA sequencing was performed on 45572 cells obtained from seven cecal samples in pigs at four different developmental stages(days(D)30,42,150,and 730).Analysis revealed 12 major cell types and 38 subtypes,as well as their distinctive genes,transcription factors,and regulons,many of which were conserved in humans.An increase in the relative proportions of CD8^(+)T and Granzyme A(low expression)natural killer T cells(GZMA^(low)NKT)cells and a decrease in the relative proportions of epithelial stem cells,Tregs,RHEX^(+)T cells,and plasmacytoid dendritic cells(pDCs)were noted across the developmental stages.Moreover,the post-weaning period exhibited an up-regulation in mitochondrial genes,COX2 and ND2,as well as genes involved in immune activation in multiple cell types.Cell-cell crosstalk analysis indicated that IBP6^(+)fibroblasts were the main signal senders at D30,whereas IBP6^(−)fibroblasts assumed this role at the other stages.NKT cells established interactions with epithelial cells and IBP6^(+)fibroblasts in the D730 cecum through mediation of GZMA-F2RL1/F2RL2 pairs.This study provides valuable insights into cellular heterogeneity and function in the pig cecum at different development stages. 展开更多
关键词 Single-cell RNA-seq CECUM Bama Xiang pigs Various developmental stages Cellular heterogeneity
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Prognostic value of neutrophil-to-lymphocyte ratio in end-stage liver disease:A meta-analysis
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作者 Xiang-Hao Cai Yun-Ming Tang +4 位作者 Shu-Ru Chen Jia-Hui Pang Yu-Tian Chong Hong Cao Xin-Hua Li 《World Journal of Hepatology》 2024年第3期477-489,共13页
BACKGROUND The neutrophil-to-lymphocyte ratio(NLR)is commonly utilized as a prognostic indicator in end-stage liver disease(ESLD),encompassing conditions like liver failure and decompensated cirrhosis.Nevertheless,som... BACKGROUND The neutrophil-to-lymphocyte ratio(NLR)is commonly utilized as a prognostic indicator in end-stage liver disease(ESLD),encompassing conditions like liver failure and decompensated cirrhosis.Nevertheless,some studies have contested the prognostic value of NLR in ESLD.AIM To investigate the ability of NLR to predict ESLD.METHODS Databases,such as Embase,PubMed,Web of Science,Cochrane Library,China National Knowledge Infrastructure,Weipu,and Wanfang,were comprehensively searched to identify studies published before October 2022 assessing the prognostic ability of NLR to predict mortality in patients with ESLD.Effect sizes were calculated using comprehensive meta-analysis software and SATAT 15.1.RESULTS A total of thirty studies involving patients with end-stage liver disease(ESLD)were included in the evaluation.Among the pooled results of eight studies,it was observed that the Neutrophil-to-Lymphocyte Ratio(NLR)was significantly higher in non-survivors compared to survivors(random-effects model:standardized mean difference=1.02,95%confidence interval=0.67-1.37).Additionally,twenty-seven studies examined the associations between NLR and mortality in ESLD patients,reporting either hazard ratios(HR)or odds ratios(OR).The combined findings indicated a link between NLR and ESLD mortality(randomeffects model;univariate HR=1.07,95%CI=1.05-1.09;multivariate HR=1.07,95%CI=1.07-1.09;univariate OR=1.29,95%CI=1.18-1.39;multivariate OR=1.29,95%CI=1.09-1.49).Furthermore,subgroup and meta-regression analyses revealed regional variations in the impact of NLR on ESLD mortality,with Asian studies demonstrating a more pronounced effect.CONCLUSION Increased NLR in patients with ESLD is associated with a higher risk of mortality,particularly in Asian patients.NLR is a useful prognostic biomarker in patients with ESLD. 展开更多
关键词 Neutrophil-to-lymphocyte ratio End stage liver diseases PROGNOSIS META-ANALYSIS MORTALITY
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Computed tomography-based radiomics diagnostic approach for differential diagnosis between early-and late-stage pancreatic ductal adenocarcinoma
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作者 Shuai Ren Li-Chao Qian +4 位作者 Ying-Ying Cao Marcus J Daniels Li-Na Song Ying Tian Zhong-Qiu Wang 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第4期1256-1267,共12页
BACKGROUND One of the primary reasons for the dismal survival rates in pancreatic ductal adenocarcinoma(PDAC)is that most patients are usually diagnosed at late stages.There is an urgent unmet clinical need to identif... BACKGROUND One of the primary reasons for the dismal survival rates in pancreatic ductal adenocarcinoma(PDAC)is that most patients are usually diagnosed at late stages.There is an urgent unmet clinical need to identify and develop diagnostic methods that could precisely detect PDAC at its earliest stages.METHODS A total of 71 patients with pathologically proved PDAC based on surgical resection who underwent contrast-enhanced computed tomography(CT)within 30 d prior to surgery were included in the study.Tumor staging was performed in accordance with the 8th edition of the American Joint Committee on Cancer staging system.Radiomics features were extracted from the region of interest(ROI)for each patient using Analysis Kit software.The most important and predictive radiomics features were selected using Mann-Whitney U test,univar-iate logistic regression analysis,and minimum redundancy maximum relevance(MRMR)method.Random forest(RF)method was used to construct the radiomics model,and 10-times leave group out cross-validation(LGOCV)method was used to validate the robustness and reproducibility of the model.RESULTS A total of 792 radiomics features(396 from late arterial phase and 396 from portal venous phase)were extracted from the ROI for each patient using Analysis Kit software.Nine most important and predictive features were selected using Mann-Whitney U test,univariate logistic regression analysis,and MRMR method.RF method was used to construct the radiomics model with the nine most predictive radiomics features,which showed a high discriminative ability with 97.7%accuracy,97.6%sensitivity,97.8%specificity,98.4%positive predictive value,and 96.8%negative predictive value.The radiomics model was proved to be robust and reproducible using 10-times LGOCV method with an average area under the curve of 0.75 by the average performance of the 10 newly built models.CONCLUSION The radiomics model based on CT could serve as a promising non-invasive method in differential diagnosis between early and late stage PDAC. 展开更多
关键词 Pancreatic ductal adenocarcinoma Radiomics Computed tomography American Joint Committee on Cancer staging
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Correlation of tumor-associated macrophage density and proportion of M2 subtypes with the pathological stage of colorectal cancer
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作者 Fouzia Fazal Muhammad Arsalan Khan +2 位作者 Sumayya Shawana Rahma Rashid Muhammed Mubarak 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第5期1878-1889,共12页
BACKGROUND Colorectal cancer(CRC)is a prevalent global malignancy with complex prognostic factors.Tumor-associated macrophages(TAMs)have shown paradoxical associations with CRC survival,particularly concerning the M2 ... BACKGROUND Colorectal cancer(CRC)is a prevalent global malignancy with complex prognostic factors.Tumor-associated macrophages(TAMs)have shown paradoxical associations with CRC survival,particularly concerning the M2 subset.AIM We aimed to establish a simplified protocol for quantifying M2-like TAMs and explore their correlation with clinicopathological factors.METHODS A cross-sectional study included histopathological assessment of paraffinembedded tissue blocks obtained from 43 CRC patients.Using CD68 and CD163 immunohistochemistry,we quantified TAMs in tumor stroma and front,focusing on M2 proportion.Demographic,histopathological,and clinical parameters were collected.RESULTS TAM density was significantly higher at the tumor front,with the M2 proportion three times greater in both zones.The tumor front had a higher M2 proportion,which correlated significantly with advanced tumor stage(P=0.04),pathological nodal involvement(P=0.04),and lymphovascular invasion(LVI,P=0.01).However,no significant association was found between the M2 proportion in the tumor stroma and clinicopathological factors.CONCLUSION Our study introduces a simplified protocol for quantifying M2-like TAMs in CRC tissue samples.We demonstrated a significant correlation between an increased M2 proportion at the tumor front and advanced tumor stage,nodal involvement,and LVI.This suggests that M2-like TAMs might serve as potential indicators of disease progression in CRC,warranting further investigation and potential clinical application. 展开更多
关键词 Colorectal cancer Macrophages Tumor stroma M2 subset Tumor front Tumor stage Lymphovascular invasion Prognosis Tumor-associated macrophages IMMUNOHISTOCHEMISTRY
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Palliative care for end-stage liver disease and acute on chronic liver failure:A systematic review
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作者 Vakaola I Pulotu Mafi Jonathan Soldera 《World Journal of Methodology》 2024年第4期131-148,共18页
BACKGROUND End stage liver disease(ESLD)represents a growing health concern characterized by elevated morbidity and mortality,particularly among individual ineligible for liver transplantation.The demand for palliativ... BACKGROUND End stage liver disease(ESLD)represents a growing health concern characterized by elevated morbidity and mortality,particularly among individual ineligible for liver transplantation.The demand for palliative care(PC)is pronounced in patients grappling with ESLD and acute on chronic liver failure(ACLF).Unfortunately,the historical underutilization of PC in ESLD patients,despite their substantial needs and those of their family caregivers,underscores the imperative of seamlessly integrating PC principles into routine healthcare practices across the entire disease spectrum.AIM To comprehensively investigate the evidence surrounding the benefits of incorporating PC into the comprehensive care plan for individuals confronting ESLD and/or ACLF.METHODS A systematic search in the Medline(PubMed)database was performed using a predetermined search command,encompassing studies published in English without any restrictions on the publication date.Subsequently,the retrieved studies were manually examined.Simple descriptive analyses were employed to summarize the results.RESULTS The search strategies yielded 721 references.Following the final analysis,32 fulllength references met the inclusion criteria and were consequently incorporated into the study.Meticulous data extraction from these 32 studies was undertaken,leading to the execution of a comprehensive narrative systematic review.The review found that PC provides significant benefits,reducing symptom burden,depressive symptoms,readmission rates,and hospital stays.Yet,barriers like the appeal of transplants and misconceptions about PC hinder optimal utilization.Integrating PC early,upon the diagnosis of ESLD and ACLF,regardless of transplant eligibility and availability,improves the quality of life for these patients.CONCLUSION Despite the substantial suffering and poor prognosis associated with ESLD and ACLF,where liver transplantation stands as the only curative treatment,albeit largely inaccessible,PC services have been overtly provided too late in the course of the illness.A comprehensive understanding of PC's pivotal role in treating ESLD and ACLF is crucial for overcoming these barriers,involving healthcare providers,patients,and caregivers. 展开更多
关键词 End stage liver disease Acute on chronic liver failure Palliative care Liver transplantation Quality of life
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Evaluation of the Effect and Efficiency of Ear Tip Bloodletting Combined with Xianfang Huoming Yin in the Treatment of Early-Stage Wheals
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作者 Ying Pang 《Journal of Clinical and Nursing Research》 2024年第2期86-91,共6页
Objective:To evaluate the effect and efficiency of ear tip bloodletting combined with Xianfang Huoming Yin(XFH)in the treatment of early-stage wheals.Methods:70 patients with early-stage wheals admitted from September... Objective:To evaluate the effect and efficiency of ear tip bloodletting combined with Xianfang Huoming Yin(XFH)in the treatment of early-stage wheals.Methods:70 patients with early-stage wheals admitted from September 2020 to September 2022 were divided into two groups by randomized numerical table method,with 35 cases/group.Both groups received conventional treatment,the control group combined with XFH,and the observation group combined with ear tip bloodletting therapy and XFH.Conscious symptom scores,ocular indexes,therapeutic effects,and sleep quality between the two groups were compared.Results:After the treatment,the patients in the observation group had lower self-awareness symptom scores and sleep quality scores as compared to those in the control group;the diameter of the mass in the observation group was smaller than that of the control group after treatment;the average tear film rupture time and the time taken for the first non-contact tear film to rupture were longer in the observation group than those in the control group;the total effective rate of the treatment in the observation group was higher than that of the control group(P<0.05).Conclusion:Ear tip bloodletting combined with XFH was ideal for the treatment of early-stage wheals and has a high effective rate. 展开更多
关键词 Early stage of wheal Ear tip bloodletting Xianfang huoming yin Effective rate
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Trajectory of Walking Function in Late-Stage Older Individuals Managed with a Regular Exercise Program: A 5-Year Longitudinal Tracking with an IoT Gait Analysis System Using Accelerometers
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作者 Taisuke Ito 《Open Journal of Therapy and Rehabilitation》 2024年第2期174-184,共11页
Purpose: This study focused on maintaining and improving the walking function of late-stage older individuals while longitudinally tracking the effects of regular exercise programs in a day-care service specialized fo... Purpose: This study focused on maintaining and improving the walking function of late-stage older individuals while longitudinally tracking the effects of regular exercise programs in a day-care service specialized for preventive care over 5 years, using detailed gait function measurements with an accelerometer-based system. Methods: Seventy individuals (17 male and 53 female) of a daycare service in Tokyo participated in a weekly exercise program, meeting 1 - 2 times. The average age of the participants at the start of the program was 81.4 years. Gait function, including gait speed, stride length, root mean square (RMS) of acceleration, gait cycle time and its standard deviation, and left-right difference in stance time, was evaluated every 6 months. Results: Gait speed and stride length improved considerably within six months of starting the exercise program, confirming an initial improvement in gait function. This suggests that regular exercise programs can maintain or improve gait function even age groups that predictably have a gradual decline in gait ability due to enhanced age. In the long term, many indicators tended to approach baseline values. However, the exercise program seemingly counteracts age-related changes in gait function and maintains a certain level of function. Conclusions: While a decline in gait ability with aging is inevitable, establishing appropriate exercise habits in late-stage older individuals may contribute to long-term maintenance of gait function. 展开更多
关键词 Late-stage Elderly Exercise Gait Function ACCELEROMETER IoT-Based Gait Analysis Device
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The Immediate Analgesic Effect and Impact on Gait Function of Transcutaneous Electrical Nerve Stimulation in Late-Stage Elderly Individuals with Knee Pain: Examination of Gait Function Using an IoT-Based Gait Analysis Device
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作者 Taisuke Ito 《Open Journal of Therapy and Rehabilitation》 2024年第2期185-195,共11页
Purpose: This study verified the effects of transcutaneous electrical nerve stimulation (TENS), which can be worn during walking and exercise, in elderly individuals with late-stage knee pain who exercise regularly. M... Purpose: This study verified the effects of transcutaneous electrical nerve stimulation (TENS), which can be worn during walking and exercise, in elderly individuals with late-stage knee pain who exercise regularly. Methods: Thirty-two late-stage elderly individuals were evaluated for knee pain during rest, walking, and program exercises, with and without TENS. Gait analysis was performed using an IoT-based gait analysis device to examine the effects of TENS-induced analgesia on gait. Results: TENS significantly reduced knee pain during rest, walking, and programmed exercises, with the greatest analgesic effect observed during walking. The greater the knee pain without TENS, the more significant the analgesic effect of TENS. A comparison of gait parameters revealed a significant difference only in the gait cycle time, with a trend towards faster walking with TENS;however, the effect was limited. Conclusion: TENS effectively relieves knee pain in late-stage elderly individuals and can be safely applied during exercise. Pain management using TENS provides important insights into the implementation of exercise therapy in this age group. 展开更多
关键词 Late-stage Elderly Knee Joint Pain Exercise Transcutaneous Electrical Stimulation IoT-Based Gait Analysis Device
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A CNN-Based Single-Stage Occlusion Real-Time Target Detection Method
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作者 Liang Liu Nan Yang +4 位作者 Saifei Liu Yuanyuan Cao Shuowen Tian Tiancheng Liu Xun Zhao 《Journal of Intelligent Learning Systems and Applications》 2024年第1期1-11,共11页
Aiming at the problem of low accuracy of traditional target detection methods for target detection in endoscopes in substation environments, a CNN-based real-time detection method for masked targets is proposed. The m... Aiming at the problem of low accuracy of traditional target detection methods for target detection in endoscopes in substation environments, a CNN-based real-time detection method for masked targets is proposed. The method adopts the overall design of backbone network, detection network and algorithmic parameter optimisation method, completes the model training on the self-constructed occlusion target dataset, and adopts the multi-scale perception method for target detection. The HNM algorithm is used to screen positive and negative samples during the training process, and the NMS algorithm is used to post-process the prediction results during the detection process to improve the detection efficiency. After experimental validation, the obtained model has the multi-class average predicted value (mAP) of the dataset. It has general advantages over traditional target detection methods. The detection time of a single target on FDDB dataset is 39 ms, which can meet the need of real-time target detection. In addition, the project team has successfully deployed the method into substations and put it into use in many places in Beijing, which is important for achieving the anomaly of occlusion target detection. 展开更多
关键词 Real-Time Mask Target CNN (Convolutional Neural Network) Single-stage Detection Multi-Scale Feature Perception
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适用于规划-运行两阶段的配电网可靠性等级划分及评估方法 被引量:1
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作者 李鹏 赵亚汝 +2 位作者 范须露 梁界飞 王加浩 《高电压技术》 EI CAS CSCD 北大核心 2024年第5期2042-2051,I0018,共11页
新型电力系统的快速建设与发展对配电网的可靠性评估提出了更高的要求。综合考虑配电网中终端用户差异化的可靠性需求和电网规划、运行两阶段的不同特点,提出了配电网可靠性等级划分方法和适用于规划-运行两阶段的配电网可靠性评估方法... 新型电力系统的快速建设与发展对配电网的可靠性评估提出了更高的要求。综合考虑配电网中终端用户差异化的可靠性需求和电网规划、运行两阶段的不同特点,提出了配电网可靠性等级划分方法和适用于规划-运行两阶段的配电网可靠性评估方法。首先,考虑用电性质、用户侧负荷特性等多方面因素,计及可靠性电价的影响,从系统侧、用户侧和供用电交互侧出发,建立了配电网供电可靠性评估指标体系;然后考虑终端用户用电需求的差异性,进行了配电网可靠性等级的划分;在此基础上,基于终端用户的差异化可靠性需求,提出了适用于规划-运行两阶段的配电网可靠性评估方法。最后进行算例分析,验证了所提划分方法的合理性和评估方法的有效性。 展开更多
关键词 可靠性评估 终端用户差异化需求 规划-运行两阶段 可靠性等级划分 熵权-层次分析法
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风电租赁储能参与电能-调频市场竞价策略
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作者 李咸善 胡长宇 +2 位作者 张远航 李欣 李飞 《电网技术》 EI CSCD 北大核心 2024年第5期1992-2002,I0057,I0054-I0056,共15页
风电参与市场化竞价运营,可有效激发风电的市场力及其主动租赁储能改善调频性能的积极性,在提升风电运营效益的同时,助力电网的调频调峰,但需解决风储调频性能指标优化及其电能-调频双市场竞价策略协同优化等关键问题。为此,提出了风电... 风电参与市场化竞价运营,可有效激发风电的市场力及其主动租赁储能改善调频性能的积极性,在提升风电运营效益的同时,助力电网的调频调峰,但需解决风储调频性能指标优化及其电能-调频双市场竞价策略协同优化等关键问题。为此,提出了风电参与电能-调频市场竞价双层优化模型:上层为双市场多主体竞价出清模型;下层为各主体竞价策略优化模型,响应上层出清结果,优化调整竞价策略,达到各主体效益最大化。下层模型嵌套了考虑风电不确定性的储能运营商与风电集群储能租赁价格/容量主从博弈优化模型。双层模型联合求解,得出最终风电集群租赁储能容量及其双市场竞价策略。算例结果表明,所提方法能够提升风电运营效益,助力电网调频调峰。 展开更多
关键词 风电集群 综合调频性能指标 不确定性 储能租赁 多主体竞价 主从博弈 两阶段鲁棒优化
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移动充电桩选址-路径优化及遗传-RSI两阶段算法
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作者 马艳芳 薛金昭 +1 位作者 李保玉 杨屹夫 《计算机工程与应用》 CSCD 北大核心 2024年第13期319-329,共11页
在我国“双碳”政策背景下,考虑载重、电量、充电桩服务能力等约束,构建以最小化总配送距离为目标的移动充电桩选址与电动汽车路径规划模型。随后,设计一种两阶段算法求解模型,第一阶段采用遗传算法规划初始配送路径,第二阶段采用RSI(re... 在我国“双碳”政策背景下,考虑载重、电量、充电桩服务能力等约束,构建以最小化总配送距离为目标的移动充电桩选址与电动汽车路径规划模型。随后,设计一种两阶段算法求解模型,第一阶段采用遗传算法规划初始配送路径,第二阶段采用RSI(recharge stations insertion)算法实现充电桩选址及路径调整。基于CVRP基准案例进行求解,结果表明车辆访问充电桩导致的配送距离平均增长率在5%以下。与粒子群和模拟退火作为一阶段的算法对比,遗传-RSI两阶段算法与这两种算法求解结果的Gap值分别为-4.04%和-3.65%。最后对“电耗率”等模型参数进行灵敏度分析。结果表明在物流公司专用电动车配送中,若使用专用充电桩并接受8%以下配送距离增长及相应的充电服务费,可采取移动充电桩选址与路径联合优化模式。 展开更多
关键词 电动汽车 移动充电桩 选址-路径问题 两阶段算法 连续型选址
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考虑风光不确定性的综合能源系统容量-成本两阶段规划优化研究
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作者 王永利 滕越 +3 位作者 袁博 窦真兰 张春雁 孙沛 《可再生能源》 CAS CSCD 北大核心 2024年第4期513-521,共9页
针对综合能源系统规划面临可再生能源波动性强、出力不确定性等问题,文章提出了一种考虑风光不确定性的综合能源系统容量-成本两阶段规划优化方法。首先,运用拉丁超立方抽样生成基础风、光场景集,并基于改进的k-means算法进行场景削减;... 针对综合能源系统规划面临可再生能源波动性强、出力不确定性等问题,文章提出了一种考虑风光不确定性的综合能源系统容量-成本两阶段规划优化方法。首先,运用拉丁超立方抽样生成基础风、光场景集,并基于改进的k-means算法进行场景削减;其次,以运行成本最低、碳减排最优、污染物减排最优构建多目标优化模型;最后,提出系统容量-成本两阶段规划优化求解策略,并选取南方某商业园区进行规划仿真。仿真结果表明,文章所构建的综合能源系统两阶段规划模型能够在保证系统经济性的同时兼顾环保性,并满足用户多种用能需求。 展开更多
关键词 综合能源系统 风光不确定性 场景削减 两阶段规划
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加减参芪地黄汤治疗慢性肾脏病3-4期的临床研究 被引量:1
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作者 任燕 段星星 +4 位作者 董宏利 李一林 蒋春波 周丽霞 周岚 《基层中医药》 2024年第1期16-21,共6页
目的探讨加减参芪地黄汤在慢性肾病3-4期患者临床治疗中的作用。方法将2019年1月至2023年5月在苏州市中医医院住院及门诊治疗的慢性肾病3-4期患者60例,按随机数字表分组,各30例。对照组在常规治疗的基础上辅以肾衰宁片口服,治疗组在常... 目的探讨加减参芪地黄汤在慢性肾病3-4期患者临床治疗中的作用。方法将2019年1月至2023年5月在苏州市中医医院住院及门诊治疗的慢性肾病3-4期患者60例,按随机数字表分组,各30例。对照组在常规治疗的基础上辅以肾衰宁片口服,治疗组在常规治疗的基础上给予加减参芪地黄汤中药治疗。检测两组患者肌酐、尿素氮、尿酸等指标,比较两组患者中医证候积分及临床疗效。结果治疗组总有效率为86.67%,显著高于对照组(77.33%)(P<0.05)。治疗组治疗后血Scr、BUN、UA显著低于对照组,差异具有统计学意义(P<0.05)。治疗组倦怠乏力、食少纳呆、腰膝酸软、肢体困重等证候积分与对照组比较均有统计学差异(P<0.01或P<0.05)。结论加减参芪地黄汤对慢性肾病3-4期患者疗效良好,可降低血肌酐、尿素氮、尿酸,改善临床症状,延缓慢性肾脏病进展。 展开更多
关键词 参芪地黄汤 慢性肾脏病3-4期 临床疗效
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基于DEMATEL-ISM的水利工程EPC项目价值增值机理研究 被引量:1
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作者 俞洪良 杨正涵 +1 位作者 徐铨彪 潘益斌 《浙江大学学报(理学版)》 CAS CSCD 北大核心 2024年第1期120-130,共11页
采用设计-采购-施工(engineering-procurement-construction,EPC)总承包模式的水利工程项目日益增多,研究其价值增值机理有利于总承包方做好项目的价值管理。从水利工程EPC项目的价值链分析入手,基于文献和专家访谈得到23个价值增值影... 采用设计-采购-施工(engineering-procurement-construction,EPC)总承包模式的水利工程项目日益增多,研究其价值增值机理有利于总承包方做好项目的价值管理。从水利工程EPC项目的价值链分析入手,基于文献和专家访谈得到23个价值增值影响因素。采用问卷调查方式得到各因素间的影响程度评分,用决策实验和评估实验(decision-making trial and evaluation laboratory,DEMATEL)法计算了各因素的中心度和原因度,结合解释结构模型(interpretative structural modeling,ISM)对数据进行分析,将价值增值因素划分为6类,构建了水利工程EPC项目价值增值的递阶模型,探究和揭示了项目价值增值的路径和机理。研究结果对水利工程EPC总承包方制订管理策略有一定启示作用。 展开更多
关键词 水利工程 设计-采购-施工(EPC)总承包 价值增值 决策实验和评估实验-解释结构模型(DEMATEL-SIM)
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福建省专利质量对海洋技术创新效率的影响——基于DEA-Tobit模型的实证研究
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作者 陈思佳 《福建金融管理干部学院学报》 2024年第1期75-84,共10页
海洋技术创新是推动海洋经济转型升级、提升海洋经济高质量发展的重要驱动力,如何提升海洋技术创新效率是当前面临的重要问题。为探讨专利质量是否影响海洋技术创新效率的提升,本文基于2007-2021年海洋统计数据,运用二阶段DEA模型测算... 海洋技术创新是推动海洋经济转型升级、提升海洋经济高质量发展的重要驱动力,如何提升海洋技术创新效率是当前面临的重要问题。为探讨专利质量是否影响海洋技术创新效率的提升,本文基于2007-2021年海洋统计数据,运用二阶段DEA模型测算福建省海洋技术创新效率,综合分析海洋科技研发效率和科技成果转化效率,进一步分析专利质量对海洋技术创新效率的影响。研究结果表明:2007-2021年福建省海洋技术创新整体效率较高,呈上升趋势;分阶段看,海洋科技研发效率总体平均水平低于科技成果转化效率。Tobit模型回归结果表明专利质量的提高对海洋技术创新整体效率及分阶段的研发效率和成果转化效率的提升均具有促进作用。此外,海洋经济规模、海洋产业结构、科研平台数、科研院校专利占比等因素对海洋技术创新效率也具有一定的影响。 展开更多
关键词 专利质量 二阶段DEA模型 TOBIT模型 海洋技术创新效率 福建省
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