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基于NodeMCU和Home Assistant的智能家居控制系统
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作者 杨骏 梁念渝 王凯 《通讯世界》 2024年第8期124-126,共3页
为了提高家居生活的舒适性和便利性,开发了一套智能家居控制系统。该系统采用节点微控制单元(NodeMCU)作为基础硬件,负责收集传感器数据并操控相关执行器件。同时,该系统利用消息队列遥测传输协议(MQTT)和WiˉFi技术构建数据传输链路。... 为了提高家居生活的舒适性和便利性,开发了一套智能家居控制系统。该系统采用节点微控制单元(NodeMCU)作为基础硬件,负责收集传感器数据并操控相关执行器件。同时,该系统利用消息队列遥测传输协议(MQTT)和WiˉFi技术构建数据传输链路。此外,该系统利用开源的Home Assistant系统建立了后台服务端,以实现数据的图形化展示。用户可通过安卓移动设备实时监控家居环境状况,并对智能设备实施控制。该系统经过严格测试,表现稳定,显著提高了家居环境的智能化程度。 展开更多
关键词 NodeMCU Home assistant 智能家居
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Improving fatigue properties of normal direction ultrasonic vibration assisted face grinding Inconel 718 by regulating machined surface integrity
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作者 Nianwei Xu Renke Kang +4 位作者 Bi Zhang Yuan Zhang Chenxu Wang Yan Bao Zhigang Dong 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第3期458-475,共18页
Fatigue properties are crucial for critical aero-engine components in extreme serviceenvironments,which are significantly affected by surface integrity(SI)indexes(especially surface topography,residual stressσ_(res),... Fatigue properties are crucial for critical aero-engine components in extreme serviceenvironments,which are significantly affected by surface integrity(SI)indexes(especially surface topography,residual stressσ_(res),and microhardness)after machining processes.Normal-direction ultrasonic vibration-assisted face grinding(ND-UVAFG)has advantages in improving the machinability of Inconel 718,but there is a competitive relationship between higher compressiveσ_(res)and higher surface roughness R_(a)in affecting fatigue strength.The lack of a quantitative relationship between multiple SI indexes and fatigue strength makes theindeterminacy of a regulatory strategy for improving fatigue properties.In this work,a model of fatigue strength(σ_f)_(sur)considering multiple SI indexes was developed.Then,high-cycle fatigue tests were carried out on Inconel 718 samples with different SI characteristics,and the influence of ND-UVAFG process parameters on SI was analyzed.Based on SI indexes data,the(σ_f)_(sur)distribution in the grinding surface layer for ND-UVAFG Inconel 718 samples was determined using the developed model,and then the fatigue crack initiation(FCI)sites were furtherpredicted.The predicted FCI sites corresponded well with the experimental results,therebyverifying this model.A strategy for improving the fatigue life was proposed in this work,which was to transfer the fatigue source from the machined surface to the bulk material by controlling the SI indexes.Finally,a critical condition of SI indexes that FCI sites appeared on the surface or in bulk material was given by fitting the predicted results.According to the critical condition,an SI field where FCI sites appeared in the bulk material could be obtained.In this field,thefatigue life of Inconel 718 samples could be improved by approximately 140%. 展开更多
关键词 surface integrity fatigue strength Inconel 718 ultrasonic assisted grinding
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Feasibility Study of Assist-Linked Brief Intervention for Substance Use Disorders in a Rural Community of Plateau State, Nigeria
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作者 Nwoga Charles Nnaemeka Audu Moses David +4 位作者 Sambo Jacob Dusu Mafai Danboyi Kwei Dakwak Samuel Joseph Ndak Andarawus Zuhumnan Babatunde Stephen 《Open Journal of Psychiatry》 2024年第3期206-222,共17页
Objective: We studied the feasibility of using Alcohol, Smoking, and Substance Involvement Screening Test (ASSIST) linked with Brief Intervention (ALBI) in treating Substance Use Disorder in Nigeria. There is a clear ... Objective: We studied the feasibility of using Alcohol, Smoking, and Substance Involvement Screening Test (ASSIST) linked with Brief Intervention (ALBI) in treating Substance Use Disorder in Nigeria. There is a clear gap in meeting the needs for treatment and care for people with drug use disorders in Nigeria with many users reporting a self-perceived need for treatment and about 40% of them wanting to receive drug treatment but were unable to access such services. Methods: ASSIST questionnaire was used to gather baseline data, and ALBI along with Motivational Interviewing (MI) was used to intervene for 6 weeks following which ASSIST score was repeated and compared with baseline. Results: Majority of the participants were aged 21 - 30 years, mostly males with (61.3%) lacking steady jobs. Lifetime prevalence of any drug use was (88.2%). Three months prevalence was nicotine (72.0%), alcohol (66.7%), cannabis (47.3%), opioids (11.8%) among others. The ASSIST scores were mostly on the severe ranges. ASSIST result after six weeks showed marked reduction. The Mean Difference (MD) in the ASSIST scores after intervention was significant for tobacco, opioids, alcohol, and cannabis. The Cohen’s D effect size was large for tobacco (1.08), alcohol (0.92) and cannabis (0.73) but low for other substances. Conclusion: ALBI along with MI was helpful in combating the menace of substance use. 展开更多
关键词 assist ALBI SUD Rural Community NIGERIA
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Inquiring Natural Language Processing Capabilities on Robotic Systems through Virtual Assistants:A Systemic Approach
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作者 Ioannis Giachos Evangelos C.Papakitsos +1 位作者 Petros Savvidis Nikolaos Laskaris 《Journal of Computer Science Research》 2023年第2期28-36,共9页
This paper attempts to approach the interface of a robot from the perspective of virtual assistants.Virtual assistants can also be characterized as the mind of a robot,since they manage communication and action with t... This paper attempts to approach the interface of a robot from the perspective of virtual assistants.Virtual assistants can also be characterized as the mind of a robot,since they manage communication and action with the rest of the world they exist in.Therefore,virtual assistants can also be described as the brain of a robot and they include a Natural Language Processing(NLP)module for conducting communication in their human-robot interface.This work is focused on inquiring and enhancing the capabilities of this module.The problem is that nothing much is revealed about the nature of the human-robot interface of commercial virtual assistants.Therefore,any new attempt of developing such a capability has to start from scratch.Accordingly,to include corresponding capabilities to a developing NLP system of a virtual assistant,a method of systemic semantic modelling is proposed and applied.For this purpose,the paper briefly reviews the evolution of virtual assistants from the first assistant,in the form of a game,to the latest assistant that has significantly elevated their standards.Then there is a reference to the evolution of their services and their continued offerings,as well as future expectations.The paper presents their structure and the technologies used,according to the data provided by the development companies to the public,while an attempt is made to classify virtual assistants,based on their characteristics and capabilities.Consequently,a robotic NLP interface is being developed,based on the communicative power of a proposed systemic conceptual model that may enhance the NLP capabilities of virtual assistants,being tested through a small natural language dictionary in Greek. 展开更多
关键词 Natural language processing Robotic systems Virtual assistant Human-robot interface
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Hierarchical Privacy Protection Model in Advanced Metering Infrastructure Based on Cloud and Fog Assistance
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作者 Linghong Kuang Wenlong Shi Jing Zhang 《Computers, Materials & Continua》 SCIE EI 2024年第8期3193-3219,共27页
The Advanced Metering Infrastructure(AMI),as a crucial subsystem in the smart grid,is responsible for measuring user electricity consumption and plays a vital role in communication between providers and consumers.Howe... The Advanced Metering Infrastructure(AMI),as a crucial subsystem in the smart grid,is responsible for measuring user electricity consumption and plays a vital role in communication between providers and consumers.However,with the advancement of information and communication technology,new security and privacy challenges have emerged for AMI.To address these challenges and enhance the security and privacy of user data in the smart grid,a Hierarchical Privacy Protection Model in Advanced Metering Infrastructure based on Cloud and Fog Assistance(HPPM-AMICFA)is proposed in this paper.The proposed model integrates cloud and fog computing with hierarchical threshold encryption,offering a flexible and efficient privacy protection solution that significantly enhances data security in the smart grid.The methodology involves setting user protection levels by processing missing data and utilizing fuzzy comprehensive analysis to evaluate user importance,thereby assigning appropriate protection levels.Furthermore,a hierarchical threshold encryption algorithm is developed to provide differentiated protection strategies for fog nodes based on user IDs,ensuring secure aggregation and encryption of user data.Experimental results demonstrate that HPPM-AMICFA effectively resists various attack strategies while minimizing time costs,thereby safeguarding user data in the smart grid. 展开更多
关键词 AMI cloud and fog assistance fuzzy comprehensive analysis hierarchical threshold encryption
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Paired Assistance:Policy Rationale and Economic Performance as Illustrated by Xizang and Xinjiang
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作者 Li Xihui Wang Guiduo +1 位作者 Duan Pengfei Huang Jixin 《China Economist》 2024年第3期70-88,共19页
This study highlights the changing priorities of China’s paired assistance throughout the past decades,as well as its theoretical implications and economic growth effects for recipient regions.Using panel data from 3... This study highlights the changing priorities of China’s paired assistance throughout the past decades,as well as its theoretical implications and economic growth effects for recipient regions.Using panel data from 32 prefecture-level cities from 1990 to 2020,this study uses the multiperiod difference-in-differences approach to examine how paired assistance has contributed to economic growth in Xizang Autonomous Region and Xinjiang Uygur Autonomous Region.The findings indicate that,first,the implementation of the paired assistance policy has boosted economic growth in Xizang and Xinjiang.Second,paired assistance has stimulated economic growth in recipient communities by improving infrastructure.Third,paired assistance has contributed to economic growth in recipient communities by providing improved public services such as education and healthcare.Improvements to public services have a relatively smaller indirect effect in short term than infrastructure development on economic growth.Yet both education and healthcare are crucial to people’s quality of life in recipient communities.This paper has refined and broadened research on the effects of paired assistance,providing preference for future policymaking. 展开更多
关键词 Chinese characteristics paired assistance multiperiod difference-in-differences assessment of policy effects
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Thoughts on Pairing Assistance to Tibet for Promoting Agricultural High-quality Development in Southern Tibet from the Perspective of Agricultural Power
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作者 Zhiguo SUN Li GAO +3 位作者 Yuanpeng SUN Guangchao CAO Xinying ZHOU Xiaoqiang LI 《Asian Agricultural Research》 2024年第3期18-24,共7页
In the new era,there is an urgent need to further promote pairing assistance to Tibet,promote the simultaneous construction of a strong agriculture in Tibet and the China's Mainland,and compose a Chinese-style mod... In the new era,there is an urgent need to further promote pairing assistance to Tibet,promote the simultaneous construction of a strong agriculture in Tibet and the China's Mainland,and compose a Chinese-style modernization.Southern Tibet,located in the southeastern part of the Tibet Autonomous Region,includes Shannan City and Nyingchi City,is a region assisted by four provincial partners including Hubei Province.This paper introduces the agricultural environment in southern Tibet,studies its agricultural characteristics,and analyzes the main issues of its pairing assistance.Taking forging the strong consciousness of the Chinese national community as the main line,the paper explores strategies for promoting agricultural high-quality development in southern Tibet through pairing assistance to Tibet from the perspective of agricultural power,and proposes some strategies,such as inheriting agricultural cultural heritage,promoting the upgrading of modern seed industry,enhancing the characteristic advantages of highland barley(naked barley)and animal husbandry industries,and developing edible fungi and cold water fish industries. 展开更多
关键词 PAIRING assistANCE to TIBET Southern TIBET Shannan CITY Nyingchi CITY AGRICULTURAL high-quality development AGRICULTURAL power
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Evaluating Methods of Visual Assistance for Workers to Improve Quality and Usability in Individualized Kitchen Cabinet Assembly
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作者 Albert Eff Michael S. J. Walter 《Journal of Computer and Communications》 2024年第2期156-172,共17页
In times of digitalisation, visual assistance systems in assembly are increasingly important. The design of these assembly systems needs to be highly complex to meet the requirements. Due to the increasing number of v... In times of digitalisation, visual assistance systems in assembly are increasingly important. The design of these assembly systems needs to be highly complex to meet the requirements. Due to the increasing number of variants in production processes, as well as shorter innovation and product life cycles, assistance systems should improve quality and reduce complexity of assembly processes. However, many large kitchen manufacturers still assemble kitchen cabinets manually, due to the high variety of components, such as rails and fittings. This paper focuses on the analysis and evaluation of virtual assistance systems to improve quality and usability in individualised kitchen cabinet assembly processes at a large German manufacturer. A solution is identified and detailed. 展开更多
关键词 Digitalisation Assembly Process Visual assistance USABILITY Human-Centred Assembly Design
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Mass-Based Environmental Factor and Energy Assessment of Microwave-Assisted Synthesized Transition Metal Nanostructures
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作者 Victor J. Law 《American Journal of Analytical Chemistry》 CAS 2024年第6期201-218,共18页
This paper describes mass-based energy phase-space projection of microwave-assisted synthesis of transition metals (zinc oxide, palladium, silver, platinum, and gold) nanostructures. The projection uses process energy... This paper describes mass-based energy phase-space projection of microwave-assisted synthesis of transition metals (zinc oxide, palladium, silver, platinum, and gold) nanostructures. The projection uses process energy budget (measured in kJ) on the horizontal axes and process density (measured in kJg−1) on the vertical axes. These two axes allow both mass usage efficiency (Environmental-Factor) and energy efficiency to be evaluated for a range of microwave applicator and metal synthesis. The metrics are allied to the: second, sixth and eleventh principle of the twelve principle of Green Chemistry. This analytical approach to microwave synthesis (widely considered as a useful Green Chemistry energy source) allows a quantified dynamic environmental quotient to be given to renewable plant-based biomass associated with the reduction of the metal precursors. Thus allowing a degree of quantification of claimed “eco-friendly” and “sustainable” synthesis with regard to waste production and energy usage. 展开更多
关键词 Microwave-assisted Synthesis Transition Metals Nanostructures Allometry Scaling Power-Law Signature Green Chemistry
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Impact of the Rapid Recovery Concept on Complications and Patient Quality of Life in the Perioperative Nursing of Robot-Assisted Radical Oesophageal Cancer
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作者 Rongrong Jiang Li Han +3 位作者 Xiaoshan Ye Jiaqi Wu Jiahuan Weng Lihui Chen 《Open Journal of Nursing》 2024年第1期1-10,共10页
Aim: This study evaluates the impact of Enhanced Recovery After Surgery (ERAS) nursing on postoperative complications and quality of life in patients undergoing robot-assisted minimally invasive esophagectomy (RAMIE).... Aim: This study evaluates the impact of Enhanced Recovery After Surgery (ERAS) nursing on postoperative complications and quality of life in patients undergoing robot-assisted minimally invasive esophagectomy (RAMIE). Methods: A total of 150 patients who underwent RAMIE from January 2020 to January 2022 at our hospital were randomly assigned to either the observation group or the control group, with 75 patients in each. The control group received standard perioperative management and nursing care, while the observation group was treated with ERAS nursing strategies. Interventions continued until discharge, and outcomes such as postoperative complications, quality of life, and nutritional status were compared between the groups. Results: The observation group exhibited a significantly lower incidence of postoperative adverse reactions compared to the control group (P ionally, all dimension scores of the Short-Form 36 Health Survey (SF-36), including the total score, were higher in the observation group (P < 0.05). Furthermore, the Nutritional Risk Screening (NRS) scores for impaired nutritional status and disease severity, along with the total NRS score, were significantly lower in the observation group compared to the control group (P Conclusion: Implementing ERAS nursing in the perioperative care of patients undergoing RAMIE is associated with reduced postoperative complications and enhanced postoperative quality of life and nutritional status. . 展开更多
关键词 Robot-assisted Radical Esophageal Cancer Surgery Rapid Rehabilitation Surgical Nursing Perioperative Period COMPLICATIONS Quality of Life
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Evaluation of Functional and Radiological Outcome of Arthroscopic-Assisted Anatomical Coracoclavicular (CC) and Acromioclavicular (AC) Ligament Reconstruction in Chronic AC Joint Dislocation
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作者 Muhammad Hafiz Daud Lim Wee Cheong +2 位作者 Ang Xi Yuan Che Wan Mohd Shaiful Nizam Siti Hawa Tahir 《Journal of Biosciences and Medicines》 2024年第3期223-237,共15页
Introduction: Acromioclavicular (AC) joint dislocation is a common shoulder injury, comprising 9% - 12% of shoulder girdle injuries. Optimal management remains challenging, with treatment decisions guided by the Rockw... Introduction: Acromioclavicular (AC) joint dislocation is a common shoulder injury, comprising 9% - 12% of shoulder girdle injuries. Optimal management remains challenging, with treatment decisions guided by the Rockwood classification system. Controversies surround grade III injuries, necessitating further classification. Non-operative treatment has shown favorable outcomes, while surgical interventions vary. Anatomical coracoclavicular reconstruction (ACCR) has demonstrated biomechanical advantages over traditional methods. Arthroscopic techniques offer advantages, minimizing deltoid detachment and allowing concurrent pathology identification. This study evaluates the outcomes of arthroscopic-assisted ACCR in chronic AC joint dislocation. Surgical Technique: Arthroscopic-assisted ACCR involves meticulous portal placement, tendon graft harvesting, diagnostic arthroscopy, and coracoid exposure. The clavicle tunnels were made to mimic the conoid and trapezoid ligament positions, using FibreTape#2 loop and Dog Bone Button for correct placement against the coracoid base, and passing the semitendinosus graft through to reconstruct the conoid ligament, reduction done and graft follow through for anatomical reconstruction. Methods: A retrospective cohort study at Hospital Kuala Lumpur analyzed 35 patients undergoing arthroscopic-assisted ACCR for Rockwood grade III - V AC joint dislocations. Inclusion criteria encompassed trauma ≥ 3 weeks prior, no prior shoulder injuries, and ≥12-month follow-up. Functional and radiological assessments utilized ASES scores and coracoclavicular distances, respectively. Statistical analysis employed descriptive statistics and logistic regression. Results: The mean age was 38.9 years (SD 11.26), and 34 of 35 patients were male. Grade IV injuries were predominant (37.1%). Waiting time for surgery averaged 234.9 days. Functional improvement was substantial postoperatively (ASES: 55.5 to 88.9). Radiological outcomes demonstrated reduced coracoclavicular distances and maintained reduction. No significant correlation was observed between injury grade and outcomes. Conclusion: Arthroscopic-assisted ACCR for chronic AC joint dislocation yields significant functional and radiological improvement, irrespective of injury grade. Waiting time for surgery exhibits minor impact on outcomes, emphasizing the procedure’s efficacy. Concomitant injuries do not impede success, highlighting the versatility of this approach in managing shoulder instability. The study contributes valuable insights into the nuanced management of chronic AC joint dislocations and supports the adoption of arthroscopic-assisted ACCR as a viable treatment option. 展开更多
关键词 Arthroscopic-assisted Anatomical Coracoclavicular and Acromioclavicular Ligament Reconstruction (AACR) Chronic Acromioclavicular Dislocation ASES Score Rockwood Classification
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基于LabVIEW和Vision Assistant的车牌识别系统设计 被引量:1
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作者 许卫洪 《无线互联科技》 2023年第7期58-60,共3页
文章提出了一种基于LabVIEW和Vision Assistant的车牌识别方案。系统使用Vision Assistant的颜色阈值、高级形态学及光学字符识别等函数,实现了对车牌图像的预处理和车牌区域定位以及车牌字符分割、字符训练和识别,使用LabVIEW程序完成... 文章提出了一种基于LabVIEW和Vision Assistant的车牌识别方案。系统使用Vision Assistant的颜色阈值、高级形态学及光学字符识别等函数,实现了对车牌图像的预处理和车牌区域定位以及车牌字符分割、字符训练和识别,使用LabVIEW程序完成车牌的显示。使用数百张车牌图像对该系统进行验证,结果证实该方案是可行的,系统是可靠的,可以快速、准确定位和识别车牌。 展开更多
关键词 车牌识别 视觉助手 车牌定位 字符分割与识别
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KOH-assisted aqueous synthesis of bimetallic metal-organic frameworks and their derived selenide composites for efficient lithium storage 被引量:3
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作者 Shuya Zhang Yanchun Xue +7 位作者 Yutang Zhang Chengxing Zhu Xingmei Guo Fu Cao Xiangjun Zheng Qinghong Kong Junhao Zhang Tongxiang Fan 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第4期601-610,共10页
To solve low efficiency,environmental pollution,and toxicity for synthesizing zeolitic imidazolate frameworks(ZIFs)in organic solvents,a KOH-assisted aqueous strategy is proposed to synthesize bimetallic ZIFs polyhedr... To solve low efficiency,environmental pollution,and toxicity for synthesizing zeolitic imidazolate frameworks(ZIFs)in organic solvents,a KOH-assisted aqueous strategy is proposed to synthesize bimetallic ZIFs polyhedrons,which are used as precursors to prepare bimetallic selenide and N-doped carbon(NC)composites.Among them,Fe–Co–Se/NC retains the three-dimensional(3D)polyhedrons with mesoporous structure,and Fe–Co–Se nanoparticles are uniform in size and evenly distributed.When assessed as anode material for lithium-ion batteries,Fe–Co–Se/NC achieves an excellent initial specific capacity of 1165.9 m Ah·g^(-1)at 1.0 A·g^(-1),and the reversible capacity of Fe–Co–Se/NC anode is 1247.4 m Ah·g^(-1)after 550 cycles.It is attributed to that the uniform composite of bimetallic selenides and N-doped carbon can effectively tune redox active sites,the stable 3D structure of Fe–Co–Se/NCs guarantees the structural stability and wettability of the electrolyte,and the uniform distribution of Fe–Co–S nanoparticles in size esuppresses the volume expansion and accelerates the electrochemical reaction kinetics. 展开更多
关键词 potassium hydroxide assisted aqueous strategy bimetallic zeolitic imidazolate frameworks bimetallic selenide lithium-ion batteries long cycle performance
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Multilayer Neural Network Based Speech Emotion Recognition for Smart Assistance 被引量:2
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作者 Sandeep Kumar MohdAnul Haq +4 位作者 Arpit Jain C.Andy Jason Nageswara Rao Moparthi Nitin Mittal Zamil S.Alzamil 《Computers, Materials & Continua》 SCIE EI 2023年第1期1523-1540,共18页
Day by day,biometric-based systems play a vital role in our daily lives.This paper proposed an intelligent assistant intended to identify emotions via voice message.A biometric system has been developed to detect huma... Day by day,biometric-based systems play a vital role in our daily lives.This paper proposed an intelligent assistant intended to identify emotions via voice message.A biometric system has been developed to detect human emotions based on voice recognition and control a few electronic peripherals for alert actions.This proposed smart assistant aims to provide a support to the people through buzzer and light emitting diodes(LED)alert signals and it also keep track of the places like households,hospitals and remote areas,etc.The proposed approach is able to detect seven emotions:worry,surprise,neutral,sadness,happiness,hate and love.The key elements for the implementation of speech emotion recognition are voice processing,and once the emotion is recognized,the machine interface automatically detects the actions by buzzer and LED.The proposed system is trained and tested on various benchmark datasets,i.e.,Ryerson Audio-Visual Database of Emotional Speech and Song(RAVDESS)database,Acoustic-Phonetic Continuous Speech Corpus(TIMIT)database,Emotional Speech database(Emo-DB)database and evaluated based on various parameters,i.e.,accuracy,error rate,and time.While comparing with existing technologies,the proposed algorithm gave a better error rate and less time.Error rate and time is decreased by 19.79%,5.13 s.for the RAVDEES dataset,15.77%,0.01 s for the Emo-DB dataset and 14.88%,3.62 for the TIMIT database.The proposed model shows better accuracy of 81.02%for the RAVDEES dataset,84.23%for the TIMIT dataset and 85.12%for the Emo-DB dataset compared to Gaussian Mixture Modeling(GMM)and Support Vector Machine(SVM)Model. 展开更多
关键词 Speech emotion recognition classifier implementation feature extraction and selection smart assistance
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Comparative study of functional optical zone:small incision lenticule extraction versus femtosecond laser assisted excimer laser keratomileusis 被引量:1
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作者 Yao-Wen Song Meng-Fan Cui +3 位作者 Yi Feng Min Qu Yan Gao Rui He 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第2期238-244,共7页
AIM:To investigate the size of functional optical zone(FOZ)after small incision lenticule extraction(SMILE)versus femtosecond laser assisted excimer laser keratomileusis(FS-LASIK)for myopia correction and potential as... AIM:To investigate the size of functional optical zone(FOZ)after small incision lenticule extraction(SMILE)versus femtosecond laser assisted excimer laser keratomileusis(FS-LASIK)for myopia correction and potential associated factors for FOZ.METHODS:A total of 133 patients who received corneal refractive surgery in our hospital between November 2018 and July 2021 were retrospectively enrolled.There were 63 patients(123 eyes)in SMILE group and 70patients(139 eyes)in FS-LASIK group.The size of FOZ was measured using Pentacam 3-dementional anterior segment analyzer before and 3mo after surgery,so as to analyze postoperative achieved functional optical zone(AFOZ)and its contributing parameters.RESULTS:When planned functional optical zone(PFOZ)was 6.5 mm for both groups,AFOZ was 1.45±0.27 and 1.67±0.25 mm smaller than preoperative FOZ in SMILE group and FS-LASIK group 3mo after surgery.AFOZ in SMILE group was significantly larger than that in FS-LASIK group(P<0.001).Variation of FOZ was negatively correlated with preoperative spherical equivalent(SE)and positively correlated with variation of mean keratometry value(△Km),variation of spherical aberration(△SA),and variation of Q-value(△Q,all P<0.001)in both groups.Multiple variable linear regression equations were△FOZ=1.354-0.1×pre-SE+0.336×△Q+1.462×△SA in SMILE group and△FOZ=1.512+0.137×△Q+0.468×△SA in FS-LASIK group.CONCLUSION:AFOZ is significantly smaller than preoperative FOZ in both SMILE and FS-LASIK groups.With the same PFOZ,larger AFOZ is achieved in SMILE group than in FS-LASIK group. 展开更多
关键词 functional optical zone small incision lenticule extraction femtosecondlaser assisted excimer laser keratomileusis spherical equivalent spherical aberration
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Adaptive Gain Tuning Rule for Nonlinear Sliding-mode Speed Control of Encoderless Three-phase Permanent Magnet Assisted Synchronous Motor 被引量:1
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作者 Ghada A.Abdel Aziz Rehan Ali Khan 《CES Transactions on Electrical Machines and Systems》 CSCD 2023年第3期301-310,共10页
In this paper, an adaptive gain tuning rule is designed for the nonlinear sliding mode speed control(NSMSC) in order to enhance the dynamic performance and the robustness of the permanent magnet assisted synchronous r... In this paper, an adaptive gain tuning rule is designed for the nonlinear sliding mode speed control(NSMSC) in order to enhance the dynamic performance and the robustness of the permanent magnet assisted synchronous reluctance motor(PMa-Syn RM) with considering the parameter uncertainties. A nonlinear sliding surface whose parameters are altering with time is designed at first. The proposed NSMSC can minimize the settling time without any overshoot via utilizing a low damping ratio at starting along with a high damping ratio as the output approaches the target set-point. In addition, it eliminates the problem of the singularity with the upper bound of an uncertain term that is hard to be measured practically as well as ensures a rapid convergence in finite time, through employing a simple adaptation law. Moreover, for enhancing the system efficiency throughout the constant torque region, the control system utilizes the maximum torque per ampere technique. The nonlinear sliding surface stability is assured via employing Lyapunov stability theory. Furthermore, a simple sliding mode estimator is employed for estimating the system uncertainties. The stability analysis and the experimental results indicate the effectiveness along with feasibility of the proposed speed estimation and the NSMSC approach for a 1.1-k W PMa-Syn RM under different speed references, electrical and mechanical parameters disparities, and load disturbance conditions. 展开更多
关键词 Permanent magnet assisted synchronous reluctance motor Nonlinear sliding mode speed control Speed estimation Parameter uncertainties Sliding mode estimator
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Spatial spillover effects of official development assistance on environmental pressure in sub-Saharan African(SSA)countries
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作者 Qiang Wang Jiaqi Guo Rongrong Li 《Geography and Sustainability》 CSCD 2023年第2期170-178,共9页
Impoverished sub-Saharan Africa(SSA)is under increasing environmental pressure from global environmental changes.It is now generally accepted in academic circles that economic development in SSA countries can cause en... Impoverished sub-Saharan Africa(SSA)is under increasing environmental pressure from global environmental changes.It is now generally accepted in academic circles that economic development in SSA countries can cause environmental pressure in other countries.However,there is research gap on the impact of economic assistance on environmental pressure in SSA countries and whether economic assistance causes spatial spillovers of environ-mental pressure between SSA countries.To better understand the impact of economic assistance on environmental pressures in SSA,a dynamic spatial Dubin panel model was developed.It helped us explore the spatial spillover effects of economic assistance on environmental pressures in recipient countries based on the panel data from 34 SSA countries.The results show that economic assistance had a positive stimulating effect on environmen-tal pressures of recipient countries,which means that the degree of human disturbance to the environment has deepened.Due to the regional correlation effect,neighboring countries were saddled with environmental pres-sures from the target country.Moreover,environmental pressures have time inertia,which can easily produce a snowball effect.The decomposition of effects shows that the impact of economic assistance on environmental pressures is relatively minor.Environmental pressures have spillover effects,so to deal with diffuse risks,joint regional prevention and control policies should be developed. 展开更多
关键词 Official development assistance Sub-Saharan African Environmental pressures Dynamic spatial Dubin panel model Economic assistance
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Assistants
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作者 Hacke.,S 《电子与电脑》 1997年第2期43-45,共3页
关键词 assistants WEB页面 编码工具 WWW
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Al-based Assistants
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作者 Adela 《新世纪智能》 2018年第23期72-73,共2页
Whether you leave business school to become a corporate manager, a professional high performer or an entrepreneur, you will spend much of your time on tasks unrelated to your expertise. Only the most senior executives... Whether you leave business school to become a corporate manager, a professional high performer or an entrepreneur, you will spend much of your time on tasks unrelated to your expertise. Only the most senior executives now have dedicated personal assistants and so the more mundane work of emails. 展开更多
关键词 Al-based assistants BUSINESS
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Spectra-assisted laser focusing in quantitative analysis of laser-induced breakdown spectroscopy for copper alloys
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作者 李守杰 郑荣儿 +5 位作者 出口祥啓 叶旺全 田野 郭金家 李颖 卢渊 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第4期204-209,共6页
Laser-induced breakdown spectroscopy(LIBS)is a capable technique for elementary analysis,while LIBS quantitation is still under development.In quantitation,precise laser focusing plays an important role because it ens... Laser-induced breakdown spectroscopy(LIBS)is a capable technique for elementary analysis,while LIBS quantitation is still under development.In quantitation,precise laser focusing plays an important role because it ensures the distance between the laser and samples.In the present work,we employed spectral intensity as a direct way to assist laser focusing in LIBS quantitation for copper alloys.It is found that both the air emission and the copper line could be used to determine the position of the sample surface by referencing the intensity maximum.Nevertheless,the fine quantitation was only realized at the position where the air emission(e.g.O(I)777.4 nm)reached intensity maximum,and also in this way,a repeatable quantitation was successfully achieved even after 120 days.The results suggested that the LIBS quantitation was highly dependent on the focusing position of the laser,and spectra-assisted focusing could be a simple way to find the identical condition for different samples’detection.In the future,this method might be applicable in field measurements for LIBS analysis of solids. 展开更多
关键词 LIBS laser focusing spectra assistance quantitative analysis copper alloys
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