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Inner-City Neighbourhood Changes Predicted from House Prices in Windsor, Ontario, since the Early- or Mid-1980s
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作者 Alan G. Phipps 《Journal of Building Construction and Planning Research》 2020年第2期138-160,共23页
Changes in prices of homes are hypothesized as correlated with the times of their sale and resale and the attributes of their dwelling unit and neighbourhood and those of neighbouring homes. They may also be correlate... Changes in prices of homes are hypothesized as correlated with the times of their sale and resale and the attributes of their dwelling unit and neighbourhood and those of neighbouring homes. They may also be correlated with the occurrences of events inside the neighbourhoods caused by the activities of </span><span style="font-family:Verdana;">individuals and organizations outside the neighbourhoods, such as whether the local economy is in a recession or has a high unemployment rate. Calibrated hybrid housing price models predict precipitous decreases in house prices of approximately 2900 sold and resold homes in two inner-city neighbourhoods</span> <span style="font-family:Verdana;">in Windsor, Ontario, during those events since 1981 or 1986. Overall modest predicted percentage increases in houses’ prices during more than 30 years therefore subsumed periods of inner-city neighbourhood deterioration i</span><span style="font-family:Verdana;">n </span><span style="font-family:Verdana;">dispersed locations of unimproved and disimproved homes. Compensatory predictions however are of increasing prices for minorities of homes with improvements to several attributes of the dwelling unit and neighbourhood. 展开更多
关键词 Neighbourhood Change House Price Local Event Hybrid Housing Price Model Inner-City Neighbourhood
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Measuring Exterior Housing Quality in Four Older-Urban Neighbourhoods in Windsor, Ontario
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作者 Alan G. Phipps 《Journal of Building Construction and Planning Research》 2016年第1期13-40,共28页
Four theoretically-deduced hypotheses about geographical and temporal variations in exterior housing quality within a neighbourhood are summarized as a renovation- or deterioration-of-self effect, a contagion-down-the... Four theoretically-deduced hypotheses about geographical and temporal variations in exterior housing quality within a neighbourhood are summarized as a renovation- or deterioration-of-self effect, a contagion-down-the-street effect, a distance-from-riverbank effect, and a distance-from core effect. These hypotheses are tested with data for the exterior conditions of hundreds of single- detached (-like) houses that have been individually surveyed twice with the same instrument in four older-urban neighbourhoods in Windsor, Ontario, Canada. Each surveyed house’s rated conditions of 12 exterior attributes are in particular utilized to calculate its overall exterior quality as a percentage above or below normal. Findings are that houses’ exteriors had average “normal” weathered conditions for Canada. Even so, overall exterior housing qualities in three neighbourhoods exemplified a hypothesized deterioration-of-self effect and proximity-to-core effect, as they had especially declined from their original survey to their resurvey for houses located near to a core such as downtown or a casino. In addition, the hypothesized distance-from-riverbank effect was observed in one neighbourhood where overall exterior housing quality linearly deteriorated with farther distance from a riverbank. Finally, overall exterior housing qualities had no observable contagion-down-the-street effect, and so, residents were not reacting positively or negatively to their neighbours’ maintenance and improvement of their homes’ exteriors. The practical implications of the study’s findings are discussed in the conclusion. 展开更多
关键词 Home Maintenance and Improvement Exterior Housing Quality Home Attributes Survey of Home Exterior Older-Urban Neighbourhoods Canada
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巴尔哲锆-铌-铍-稀土矿床成矿精细过程研究
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作者 吴鸣谦 马甲栋 +3 位作者 邓军 刁习 裴磊 邱昆峰 《岩石学报》 SCIE EI CAS CSCD 北大核心 2024年第6期1817-1836,共20页
巴尔哲碱性花岗岩型关键金属矿床拥有世界级Zr、Nb、Be、REE资源量,其成矿具有多期次、多阶段特征。Zr矿化(Ⅰ阶段)发生在岩浆期,表现为多锆相(agpaitic)界熔花岗岩熔体结晶出原生钠锆硅酸盐(斜钠锆石),在该阶段,多锆相界熔花岗岩经历... 巴尔哲碱性花岗岩型关键金属矿床拥有世界级Zr、Nb、Be、REE资源量,其成矿具有多期次、多阶段特征。Zr矿化(Ⅰ阶段)发生在岩浆期,表现为多锆相(agpaitic)界熔花岗岩熔体结晶出原生钠锆硅酸盐(斜钠锆石),在该阶段,多锆相界熔花岗岩经历钠质交代,斜钠锆石原位分解为锆石-石英假象,假象中锆石U-Pb年代学表明锆成矿发生在123.9±0.6Ma。随后,Nb-Be-REE矿化以多种矿物形式、分三个连续的阶段(Ⅱ、Ⅲ、Ⅳ阶段)、呈浸染状分布于遭受赤铁矿化的界熔花岗岩中,重稀土为主的矿物普遍形成于以轻稀土为主的矿物之前。Ⅱ阶段是巴尔哲矿床中Nb、Be和重稀土矿化的主要阶段,大部分界熔花岗岩均遭受了不同程度的赤铁矿化,并伴随钇兴安石、铈兴安石、钇易解石、铌铁矿等稀有稀土金属矿物的形成,主要形成以石英为主的假象(Nb-Be-REE假象),Nb-Be-REE假象的前体矿物并非某种Nb-Be-REE矿物。Ⅲ阶段主要形成黑稀金矿、独居石及氟碳铈矿,热液独居石U-Pb年代学指示该阶段热液成矿活动发生在122.8±0.6Ma。氟铈矿和氟碳钙铈矿部分交代氟碳铈矿构成了Ⅳ阶段的矿物组合。Nb、Be和REE在热液过程中的多阶段分配和富集,是造成巴尔哲矿床中复杂矿石矿物组合以及高品位Nb-Be-REE矿化的重要原因。Nb-Be-REE矿石矿物组合中不存在锆石,且其分布与雪球石英、钠质交代和锆石-石英假象的分布没有时空关联。此外,巴尔哲角闪石中Nb、Be、REE的含量低,表明原生锆硅酸盐矿物和角闪石不是Nb、Be和REE等关键金属的物质来源。结合各岩相中角闪石元素含量的变化与熔体包裹体成分特征,笔者提出Nb和REE的富集可能是氟化物-硅酸盐熔体不混溶耦合岩浆期后热液富集的结果。因此,巴尔哲矿床中需要开展精细的熔体/流体包裹体成分研究,针对关键金属尤其是Be的来源、熔-流体演化历程以及矿化精细过程开展更深入的研究。 展开更多
关键词 巴尔哲 碱性花岗岩 关键金属 岩浆-热液过程
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西方论辩研究传统视野中的逻辑与修辞——加拿大温莎大学哲学系汉斯·汉森教授访谈录
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作者 汪建峰 汉斯·汉森 《外国语言文学》 2024年第4期126-132,共7页
汉斯·汉森教授是加拿大籍哲学家,是国际论辩研究领域知名学者。如访谈所示,其研究一向以逻辑为旨归。本次访谈的内容涉及西方论辩研究的三个路径、逻辑作为中国论辩(证)研究的主流范式、论辩与举证责任、推定与认定、非形式逻辑的... 汉斯·汉森教授是加拿大籍哲学家,是国际论辩研究领域知名学者。如访谈所示,其研究一向以逻辑为旨归。本次访谈的内容涉及西方论辩研究的三个路径、逻辑作为中国论辩(证)研究的主流范式、论辩与举证责任、推定与认定、非形式逻辑的谬误研究以及政治修辞与论辩等。笔者希冀通过本次访谈来引发国内论辩学者的反思,对国内大学哲学系开展逻辑学研究、大学批判性思维(思辨性)课堂教材内容等进行梳理和自我批评,增进对于论辩(论证)的理解,从理论和实践两个层面提升论辩效果。 展开更多
关键词 讲道理 论证 逻辑 辩证 修辞
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Low-Cost Federated Broad Learning for Privacy-Preserved Knowledge Sharing in the RIS-Aided Internet of Vehicles 被引量:1
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作者 Xiaoming Yuan Jiahui Chen +4 位作者 Ning Zhang Qiang(John)Ye Changle Li Chunsheng Zhu Xuemin Sherman Shen 《Engineering》 SCIE EI CAS CSCD 2024年第2期178-189,共12页
High-efficiency and low-cost knowledge sharing can improve the decision-making ability of autonomous vehicles by mining knowledge from the Internet of Vehicles(IoVs).However,it is challenging to ensure high efficiency... High-efficiency and low-cost knowledge sharing can improve the decision-making ability of autonomous vehicles by mining knowledge from the Internet of Vehicles(IoVs).However,it is challenging to ensure high efficiency of local data learning models while preventing privacy leakage in a high mobility environment.In order to protect data privacy and improve data learning efficiency in knowledge sharing,we propose an asynchronous federated broad learning(FBL)framework that integrates broad learning(BL)into federated learning(FL).In FBL,we design a broad fully connected model(BFCM)as a local model for training client data.To enhance the wireless channel quality for knowledge sharing and reduce the communication and computation cost of participating clients,we construct a joint resource allocation and reconfigurable intelligent surface(RIS)configuration optimization framework for FBL.The problem is decoupled into two convex subproblems.Aiming to improve the resource scheduling efficiency in FBL,a double Davidon–Fletcher–Powell(DDFP)algorithm is presented to solve the time slot allocation and RIS configuration problem.Based on the results of resource scheduling,we design a reward-allocation algorithm based on federated incentive learning(FIL)in FBL to compensate clients for their costs.The simulation results show that the proposed FBL framework achieves better performance than the comparison models in terms of efficiency,accuracy,and cost for knowledge sharing in the IoV. 展开更多
关键词 Knowledge sharing Internet of Vehicles Federated learning Broad learning Reconfigurable intelligent surfaces Resource allocation
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Optimization of chemistry and process parameters for control of intermetallic formation in Mg sludges
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作者 Y.Fu G.G.Wang +4 位作者 A.Hu Y.Li K.B.Thacker J.P.Weiler H.Hu 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第4期1431-1448,共18页
Intermetallic formation in sludge during magnesium(Mg)melting,holding and high pressure die casting practices is a very important issue.But,very often it is overlooked by academia,original equipment manufacturers(OEM)... Intermetallic formation in sludge during magnesium(Mg)melting,holding and high pressure die casting practices is a very important issue.But,very often it is overlooked by academia,original equipment manufacturers(OEM),metal ingot producers and even die casters.The aim of this study was to minimize the intermetallic formation in Mg sludge via the optimization of the chemistry and process parameters.The Al8Mn5 intermetallic particles were identified by the microstructure analysis based on the Al and Mn ratio.The design of experiment(DOE)technique,Taguchi method,was employed to minimize the intermetallic formation in the sludge of Mg alloys with various chemical compositions of Al,Mn,Fe,and different process parameters,holding temperature and holding time.The sludge yield(SY)and intermetallic size(IS)was selected as two responses.The optimum combination of the levels in terms of minimizing the intermetallic formation were 9 wt.%Al,0.15 wt.%Mn,0.001 wt.%(10 ppm)Fe,690℃ for the holding temperature and holding at 30 mins for the holding time,respectively.The best combination for smallest intermetallic size were 9 wt.%Al,0.15 wt.%Mn,0.001 wt.%(10 ppm)Fe,630℃ for the holding temperature and holding at 60 mins for the holding time,respectively.Three groups of sludge factors,Chemical Sludge(CSF),Physical Sludge(PSF)and Comprehensive Sludge Factors(and CPSF)were established for prediction of sludge yields and intermetallic sizes in Al-containing Mg alloys.The CPSF with five independent variables including both chemical elements and process parameters gave high accuracy in prediction,as the prediction of the PSF with only the two processing parameters of the melt holding temperature and time showed a relatively large deviation from the experimental data.The Chemical Sludge Factor was primarily designed for small ingot producers and die casters with a limited melting and holding capacity,of which process parameters could be fixed easily.The Physical Sludge Factor could be used for mass production with a single type of Mg alloy,in which the chemistry fluctuation might be negligible.In large Mg casting suppliers with multiple melting and holding furnaces and a number of Mg alloys in production,the Comprehensive Sludge Factor should be implemented to diminish the sludge formation. 展开更多
关键词 Magnesium sludge Al-Mn intermetallic OPTIMIZATION Taguchi method Sludge factor Chemical composition Process parameter
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一带一路背景下基于加权Owen值的多层次合作分配策略
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作者 于晓辉 李武 李汉章 《运筹学学报(中英文)》 CSCD 北大核心 2024年第2期58-70,共13页
联盟结构合作对策一般涉及两个层次合作:局中人先组成小联盟,然后再以小联盟整体参与大联盟的合作。由于一带一路倡议中小联盟群体参与合作项目往往话语权有限,容易处于收益分配的劣势,从而影响参与合作项目的积极性,因而有必要对联盟... 联盟结构合作对策一般涉及两个层次合作:局中人先组成小联盟,然后再以小联盟整体参与大联盟的合作。由于一带一路倡议中小联盟群体参与合作项目往往话语权有限,容易处于收益分配的劣势,从而影响参与合作项目的积极性,因而有必要对联盟结构合作对策及其求解方法做进一步的研究。基于此,我们首先构造一种能够考虑小联盟规模对合作影响的新求解方法——加权Owen值。然后,基于联盟结构合作对策与加权Owen值刻画一带一路倡议下的多层次、复杂交叉的合作关系,获得各个单位参与跨境合作项目可能的收益分配范围及性质。最后,通过算例演示了联盟结构合作对策分配策略的计算方法。因此,基于加权Owen值计算各个单位参与跨境合作项目可能的收益分配范围,为跨境合作的大项目提供一定的决策依据。 展开更多
关键词 合作 联盟结构 加权
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Local Adaptive Gradient Variance Attack for Deep Fake Fingerprint Detection
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作者 Chengsheng Yuan Baojie Cui +2 位作者 Zhili Zhou Xinting Li Qingming Jonathan Wu 《Computers, Materials & Continua》 SCIE EI 2024年第1期899-914,共16页
In recent years,deep learning has been the mainstream technology for fingerprint liveness detection(FLD)tasks because of its remarkable performance.However,recent studies have shown that these deep fake fingerprint de... In recent years,deep learning has been the mainstream technology for fingerprint liveness detection(FLD)tasks because of its remarkable performance.However,recent studies have shown that these deep fake fingerprint detection(DFFD)models are not resistant to attacks by adversarial examples,which are generated by the introduction of subtle perturbations in the fingerprint image,allowing the model to make fake judgments.Most of the existing adversarial example generation methods are based on gradient optimization,which is easy to fall into local optimal,resulting in poor transferability of adversarial attacks.In addition,the perturbation added to the blank area of the fingerprint image is easily perceived by the human eye,leading to poor visual quality.In response to the above challenges,this paper proposes a novel adversarial attack method based on local adaptive gradient variance for DFFD.The ridge texture area within the fingerprint image has been identified and designated as the region for perturbation generation.Subsequently,the images are fed into the targeted white-box model,and the gradient direction is optimized to compute gradient variance.Additionally,an adaptive parameter search method is proposed using stochastic gradient ascent to explore the parameter values during adversarial example generation,aiming to maximize adversarial attack performance.Experimental results on two publicly available fingerprint datasets show that ourmethod achieves higher attack transferability and robustness than existing methods,and the perturbation is harder to perceive. 展开更多
关键词 FLD adversarial attacks adversarial examples gradient optimization transferability
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Oral Administration of Nicotinamide Mononucleotide with Bioenhancer BioPerine® Increases the Serum Concentration of Nicotinamide Adenine Dinucleotide in Healthy Human Volunteers: A Pilot, Open-Label, Cross-Over Study
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作者 Anju Majeed Shaheen Majeed +4 位作者 Thontadarya Shivakumar Satish Gudimallam Kadlajji Parameshwarappa Avinash Vasantha Nagaraju Lakshmi Mundkur 《Advances in Bioscience and Biotechnology》 CAS 2024年第10期573-589,共17页
Background: Bioenhancers augment the bioavailability of co-administered molecules without showing any significant effect on their own. Piperine, an alkaloid from Piper nigrum, is an established natural bioenhancer. Ni... Background: Bioenhancers augment the bioavailability of co-administered molecules without showing any significant effect on their own. Piperine, an alkaloid from Piper nigrum, is an established natural bioenhancer. Nicotinamide mononucleotide (NMN), an antiaging supplement, is the precursor of coenzyme nicotinamide adenine dinucleotide (NAD) that plays an important role in intracellular redox reactions. Objective: The study compared the serum concentrations of NAD in normal healthy participants, supplemented with NMN 500 mg and NMN 500 mg + 5 mg BioPerine® (95% piperine). Methods: In a randomized, open-label, crossover study, NMN (500 mg) was compared to NMN + BioPerine® (500 mg + 5 mg) in 6 healthy adults, aged 18 - 45 years. The participants received a single oral dose of NMN or NMN + BioPerine® capsules with 240 mL water, and blood samples were collected over 8hr. After a 4-day washout period, the same procedures were repeated as per the crossover design. Total NAD (NADtotal), including oxidized NAD (the oxidized) and its reduced form NADH, was measured in human serum samples. Results: The maximum concentration (Cmax) of NAD in serum was higher with NMN + BioPerine® (282 pmol/mL) compared to NMN (246 pmol/mL) alone. In the presence of BioPerine®, the NAD concentrations reached 257 pmol/mL during the first 2 hr, whereas a comparable serum concentration (246 pmol/mL) was attained only after 6 hr in NMN alone. The AUC0-8hr was 1738 pmol/mL/hr in NMN compared to 2004 pmol/mL/hr in NMN+ BioPerine®. The time to reach peak concentration (t1/2) was similar (6hr) in both groups. No clinically relevant adverse events (AE) were observed, and safety parameters remained within normal ranges in all the participants with both formulations. Conclusion: These results reveal that BioPerine® can effectively increase the NAD concentrations in the serum following NMN supplementation in healthy volunteers. The present study was registered prospectively with the Clinical Trials Registry-India (CTRI/2023/11/059982). 展开更多
关键词 BIOAVAILABILITY BioPerine® Nicotinamide Mononucleotide Nicotinamide Adenine Dinucleotide Bioenhancer
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Stroke Patients’ Reintegration into Normal Living Post-Discharge from Inpatient Rehabilitation: An Integrative Review
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作者 Eric F. Tanlaka Omotunmise Agbeyangi +1 位作者 Adam Mulcaster Edward Cruz 《Open Journal of Therapy and Rehabilitation》 2024年第3期274-300,共27页
Background: Stroke rehabilitation professionals have historically focused rehabilitation on physical functions and overlooked the concept of community reintegration after discharge from inpatient rehabilitation. The l... Background: Stroke rehabilitation professionals have historically focused rehabilitation on physical functions and overlooked the concept of community reintegration after discharge from inpatient rehabilitation. The lack of focus on psychosocial functions post-stroke may lead to lower levels of satisfaction during community reintegration. Methods: This integrative review synthesized findings from research literature on stroke patients’ reintegration into the community after inpatient rehabilitation to address three research questions: a) What specific physical and psychosocial functions have been identified as predictors of successful reintegration into normal living after stroke?, b) How do physical and psychosocial functions promote successful reintegration into normal living after stroke?, and c) What factors have been identified that hinder stroke patients’ reintegration into normal living after stroke? Results: A systematic search of literature identified sixteen studies that provided significant context for the research questions. What physical and psychosocial functions of stroke patients included, for example, improved mobility, independence in daily activities, reduced disability, psychological well-being, self-efficacy, social support, and personal relationships. How physical and psychosocial functions promote reintegration included, for example, disability management, emotional well-being, self-care independence, sense of purpose, and employment influence. Factors that hinder stroke patients’ reintegration consisted of longer stride time, impaired balance/mobility, activities limitation, severe stroke, presence of comorbidity, depressive symptoms, speech and language challenges, inadequate self-efficacy, fear of falling, older age, low educational level, lack of social support, and social isolation. Conclusion: Successful community reintegration after stroke requires a shift of focus from rehabilitation interventions that target physical functions to include interventions that address psychosocial functions. 展开更多
关键词 STROKE Outpatient Rehabilitation Community Reintegration Normal Living Functional Abilities
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Impaired Cognition and Stroke Rehabilitation Outcomes: Are They Related?
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作者 Eric F. Tanlaka Torri Trojand 《Open Journal of Therapy and Rehabilitation》 2024年第2期101-116,共16页
Background: Stroke survivors who exhibit impaired cognition at admission to inpatient rehabilitation may experience participation challenges and poorer functional outcomes than those without impaired cognition. Differ... Background: Stroke survivors who exhibit impaired cognition at admission to inpatient rehabilitation may experience participation challenges and poorer functional outcomes than those without impaired cognition. Differences in functional outcomes between stroke survivors with and without impaired cognition may be attributed to age, level of cognitive impairment, and severity of stroke. Materials and Methods: A retrospective secondary data analysis was conducted using health-related administrative data acquired from a Southwestern Ontario hospital’s stroke rehabilitation database. The aim was to explore potential linkages between post-stroke impaired cognition and functional gains, rehabilitation stays, and living settings after discharge from rehabilitation. Results: An aggregate sample of 393 males and 314 females subclassified as experiencing mild, moderate, and severe stroke was analyzed. At inpatient rehabilitation admission, 21.5% (n = 152) of these patients had no impaired cognition, 33.7% (n = 238) had mild impaired cognition, 22.2% (n = 157) had moderate impaired cognition, and 22.6% (n = 160) had severe impaired cognition. Cognitively impaired stroke patients were significantly (p 0.001) older, had (mostly) moderate to severe stroke with significantly (p = 0.012) more moderate cognitive impairment, had significantly (p 0.001) longer rehabilitation stays, and a high propensity for being discharged to longer-term care facilities compared to non-cognitively impaired patients. Conclusion: Presence of significant dissimilarity in rehabilitation stays and post-discharge destinations among stroke survivors with and without cognitive impairment is attributed to the age of the patient, level of cognitive impairment, and rigorous rehabilitation interventions. 展开更多
关键词 STROKE Impaired Cognition Inpatient Rehabilitation Functional Outcomes
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Mechanical Evaluation of AZ80 Magnesium Alloy in Cast Wrought Form
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作者 Peilin Ying Anita Hu +1 位作者 Wutian Shen Henry Hu 《Journal of Materials Science and Chemical Engineering》 2024年第4期119-125,共7页
Wrought magnesium alloy AZ80 with a thick section of 20 mm was prepared by squeeze casting (SC) and permanent steel mold casting (PSMC). The porosity measurements of the SC and PSMC depicted that SC AZ80 had a pore co... Wrought magnesium alloy AZ80 with a thick section of 20 mm was prepared by squeeze casting (SC) and permanent steel mold casting (PSMC). The porosity measurements of the SC and PSMC depicted that SC AZ80 had a pore content of 0.52%, which was 77% lower than 2.21% of PSMC AZ80 counterpart. The YS, UTS, e<sub>f</sub>, E and strengthening rate of cast AZ80 were determined by mechanical pulling. The engineering stress versus strain bended lines showed that SC AZ80 had a YS of 84.7 MPa, a UTS of 168.2 MPa, 5.1% in e<sub>f</sub>, and 25.1 GPa in modulus. But, the YS, UTS and e<sub>f</sub> of the PSMC AZ80 specimen were only 71.6 MPa, 109.0 MPa, 1.9% and 21.9 GPa. The findings of the mechanical pulling evidently depicted that the YS, UTS, e<sub>f</sub> and E of SC AZ80 were 18%, 54%, 174% and 15% higher than PSMC counterpart. The computed resilience and toughness suggested that the SC AZ80 exhibited greater resistance to tensile loads during elastic deformation and possessed higher capacity to absorb energy during plastic deformation compared to the PSMC AZ80. At the beginning of permanent change, the strengthening rate of SC AZ80 was 10,341 MPa, which was 9% greater than 9489 MPa of PSMC AZ80. The high mechanical characteristics of SC AZ80 should be primarily attributed to its low porosity level. . 展开更多
关键词 Squeeze Casting Wrought Magnesium Alloy AZ80 POROSITY Tensile Prop-erties
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Recombinant vaccines:Current updates and future prospects
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作者 Vivek Kumar Anuj Verma +5 位作者 Riddhi Singh Priyanshi Garg Santosh Kumar Sharma Himanshu Narayan Singh Santosh Kumar Mishra Sanjay Kumar 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2024年第8期338-350,共13页
Recombinant technology-based vaccines have emerged as a highly effective way to prevent a wide range of illnesses.The technology improved vaccine manufacturing,rendering it more efficient and economical.These vaccines... Recombinant technology-based vaccines have emerged as a highly effective way to prevent a wide range of illnesses.The technology improved vaccine manufacturing,rendering it more efficient and economical.These vaccines have multiple advantages compared to conventional vaccines.The pandemic has heightened awareness of the advantages of these vaccine technologies;trust and acceptance of these vaccines are steadily growing globally.This work offers an overview of the prospects and advantages associated with recombinant vaccines.Additionally,it discusses some of the challenges likely to arise in the future.Their ability to target diverse pathogen classes underscores their contributions to preventing previously untreatable diseases(especially vector-borne and emerging diseases)and hurdles faced throughout the vaccine development process,especially in enhancing the effectiveness of these vaccines.Moreover,their compatibility with emerging vaccination platforms of the future like virus-like particles and CRISPR/Cas9 for the production of next-generation vaccines may offer many prospects.This review also reviewed the hurdles faced throughout the vaccine development process,especially in enhancing the effectiveness of these vaccines against vector-borne diseases,emerging diseases,and untreatable diseases with high mortality rates like AIDS as well as cancer. 展开更多
关键词 MALARIA DENGUE Emerging diseases IMMUNOINFORMATICS Virus-like particles CRISPR-Cas9
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莺歌海盆地异常裂后沉降的动力学机制 被引量:25
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作者 崔涛 解习农 +1 位作者 任建业 张成 《地球科学(中国地质大学学报)》 EI CAS CSCD 北大核心 2008年第3期349-356,共8页
为了理解莺歌海盆地形成与演化的动力过程,用回剥法和应变速率反演方法对该区的钻井和地层剖面资料进行了研究.研究结果表明莺歌海盆地观测得到的裂后沉降和模拟预测的理论裂后沉降结果存在较大差异,其中在西北部为300~500m,中部和东... 为了理解莺歌海盆地形成与演化的动力过程,用回剥法和应变速率反演方法对该区的钻井和地层剖面资料进行了研究.研究结果表明莺歌海盆地观测得到的裂后沉降和模拟预测的理论裂后沉降结果存在较大差异,其中在西北部为300~500m,中部和东南部为900~1200m,其异常裂后沉降明显呈现向东南和向海方向递大的趋势.地幔对流模型预测的结果表明,20Ma以来南海北部边缘的动力地貌沉降量为300m,因此,莺歌海盆地裂后异常沉降在300m左右的地区可以用动力地貌沉降机理来解释,但是盆地中部和东南部的巨厚的异常沉降远大于动力地貌沉降量,它是自晚中新世以来盆缘断层的右旋走滑作用、裂后热回沉和动力地貌沉降共同作用的结果. 展开更多
关键词 莺歌海盆地 构造沉降 动力地貌 异常沉降 应变速率反演
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基于曲率滤波和改进GMM的钢轨缺陷自动视觉检测方法 被引量:14
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作者 张辉 金侠挺 +2 位作者 Wu Q.M.Jonathan 贺振东 王耀南 《仪器仪表学报》 EI CAS CSCD 北大核心 2018年第4期181-194,共14页
针对传统钢轨检测技术的效率低下、精度不足、安全隐患等问题,提出了基于曲率滤波和改进高斯混合模型(GMM)的钢轨表面缺陷检测方法。首先,提出了基于垂直投影的区域定位算法和灰度对比算法,克服现场工况复杂、轨面反射不均、信道噪声... 针对传统钢轨检测技术的效率低下、精度不足、安全隐患等问题,提出了基于曲率滤波和改进高斯混合模型(GMM)的钢轨表面缺陷检测方法。首先,提出了基于垂直投影的区域定位算法和灰度对比算法,克服现场工况复杂、轨面反射不均、信道噪声干扰的难题;考虑到图像信号受强工况噪声干扰,研究了具有隐式计算和曲面保持特性的曲率滤波法进行图像去噪;建立了基于马尔科夫随机场(MRF)的高斯混合模型完成表面缺陷的精确快速分割。最后,设计了"区域定位-灰度均衡化-滤波-分割"的实验流程,实验结果验证了算法的有效性,检测性能达到了精确度92.0%,相比其他方法更加精确、快速,具有更好的鲁棒性。 展开更多
关键词 钢轨表面缺陷 视觉检测 曲率滤波 马尔科夫随机场 改进高斯混合模型
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磁化率各向异性的原理及应用实例 被引量:10
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作者 张淑伟 杨振宇 +5 位作者 王喜生 Maria TCioppa 乔彦松 霍俊杰 Edgardo Caón-Tapia 赵越 《地质力学学报》 CSCD 北大核心 2017年第1期135-140,共6页
磁化率各向异性(AMS)在地质领域中的应用极为广泛,可以用来研究古流向造成的磁性矿物的定向排列,以及构造应力作用引起的岩石内磁性矿物的定向重结晶、定向排列及韧性变形。本文介绍了AMS的基本原理和参数,并并介绍了前人及作者应用AMS... 磁化率各向异性(AMS)在地质领域中的应用极为广泛,可以用来研究古流向造成的磁性矿物的定向排列,以及构造应力作用引起的岩石内磁性矿物的定向重结晶、定向排列及韧性变形。本文介绍了AMS的基本原理和参数,并并介绍了前人及作者应用AMS详细分析研究了二个实例:(1)以假多畴(MD)高钛磁铁矿为主要载磁矿物的玄武岩样品的AMS变化及其对构造运动的响应;(2)以MD磁铁矿为主要载磁矿物的湖泊沉积物样品在沉积过程中AMS变化。AMS可以灵敏地检测样品中磁性矿物的定向排列,因此在在地质领域中具有很好的应用前景。 展开更多
关键词 磁化率各向异性 磁铁矿 玄武岩 湖泊沉积物 岩石磁学
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体育锻炼对非正式结构体育社团成员主观幸福感影响的实证研究——基于心理资本的中介 被引量:18
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作者 谭延敏 张文月 张铁明 《武汉体育学院学报》 CSSCI 北大核心 2020年第9期64-71,共8页
对体育锻炼与主观幸福感关系进行探讨有利于人们健康生活方式的养成。采用心理资本与主观幸福感的2个修订量表,对武陵山片区1226名非正式结构体育社团成员进行调查,构建了体育锻炼对主观幸福感影响的心理资本中介模型。结果显示非正式... 对体育锻炼与主观幸福感关系进行探讨有利于人们健康生活方式的养成。采用心理资本与主观幸福感的2个修订量表,对武陵山片区1226名非正式结构体育社团成员进行调查,构建了体育锻炼对主观幸福感影响的心理资本中介模型。结果显示非正式结构体育社团成员的锻炼时长、锻炼频次和指导情况可分别正向预测主观幸福感和心理资本;心理资本可正向预测主观幸福感;心理资本在锻炼时长对主观幸福感预测中起着部分中介作用,在锻炼频次、指导情况对主观幸福感预测中起着完全中介作用。 展开更多
关键词 运动心理学 体育锻炼 主观幸福感 心理资本 非正式结构体育社团 调查研究
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太行山区深层次推覆构造的发现及其地质意义 被引量:11
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作者 李江海 牛向龙 +2 位作者 陈征 T.Kusky A.Polat 《自然科学进展》 北大核心 2004年第10期1118-1127,共10页
围绕太行山区龙泉关剪切带及其区域构造对比 ,报道了太行山区新太古代基底内新发现的深层次推覆构造 ,包括低角度逆冲剪切带、大规模平卧褶皱、近水平构造面理等 .这些构造揭示了该区地壳演化过程涉及大规模水平缩短变形 ,其构造样式完... 围绕太行山区龙泉关剪切带及其区域构造对比 ,报道了太行山区新太古代基底内新发现的深层次推覆构造 ,包括低角度逆冲剪切带、大规模平卧褶皱、近水平构造面理等 .这些构造揭示了该区地壳演化过程涉及大规模水平缩短变形 ,其构造样式完全可以与典型碰撞造山带前陆区进行对比 .初步提出太行山区中深地壳层次构造样式及其垂向变化规律 ,以及前陆地区基底杂岩与表壳岩系构造叠置的意义 . 展开更多
关键词 推覆构造 地质意义 新太古代 碰撞造山带 表壳岩 地壳演化 剪切带 太行山区 垂向变化 深层
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混合稀土对AlMg5Si1铝合金铸态组织与性能的影响 被引量:3
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作者 王洪飞 孔维兵 +1 位作者 胡心平 HU Henry 《铸造》 CAS CSCD 北大核心 2016年第3期253-257,共5页
通过SEM、EDS和XRD研究了不同质量分数的混合稀土对Al Mg5Si1合金组织与性能的影响。结果表明,稀土可以有效地细化合金晶粒组织,并且提高合金的强韧性。稀土含量为0.7%时合金的抗拉强度最高为194.8 MPa,伸长率为3.3%,比未加稀土的合金... 通过SEM、EDS和XRD研究了不同质量分数的混合稀土对Al Mg5Si1合金组织与性能的影响。结果表明,稀土可以有效地细化合金晶粒组织,并且提高合金的强韧性。稀土含量为0.7%时合金的抗拉强度最高为194.8 MPa,伸长率为3.3%,比未加稀土的合金抗拉强度和伸长率分别提高了33.0%和153.8%。试验分析还表明,在RE含量低于0.7%时,RE晶粒细化对合金的强韧化的作用能足以抵消针状的不规则多边形Mg2Si对基体的割裂作用。 展开更多
关键词 混合稀土 AL Mg5Si1 微观组织 晶粒细化 强韧性
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基于改进马尔可夫随机场的钢轨缺陷分割 被引量:4
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作者 张辉 李平 +1 位作者 QMJonathan WU 贺振东 《计算机工程与设计》 北大核心 2020年第4期1052-1061,共10页
为提高钢轨缺陷分割对噪声的鲁棒性,提出一种基于改进马尔可夫随机场(MRF)的钢轨缺陷分割方法。利用背景差分法对灰度进行预处理,消除灰度分布不均的干扰。对模糊if-then规则的前提部分采用马尔可夫随机场来利用图像中的空间约束,结果... 为提高钢轨缺陷分割对噪声的鲁棒性,提出一种基于改进马尔可夫随机场(MRF)的钢轨缺陷分割方法。利用背景差分法对灰度进行预处理,消除灰度分布不均的干扰。对模糊if-then规则的前提部分采用马尔可夫随机场来利用图像中的空间约束,结果部分指定像素距离图算法,通过使用马尔可夫随机场(MRF)在相邻像素图像之间并入局部空间信息,推导出新的自适应模糊集和MRF相结合的钢轨表面缺陷自动分割方法。建立标准的FCM、GMM和该方法的钢轨缺陷分割对比实验,验证了算法的有效性和优越性。 展开更多
关键词 钢轨缺陷 背景差分 马尔可夫随机场 空间信息 缺陷分割
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