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Chinese Calligraphy Word Spotting Using Elastic HOG Feature and Derivative Dynamic Time Warping 被引量:1
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作者 Yong Xia Zhi-Bo Yang Kuan-Quan Wang 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2014年第2期21-27,共7页
Chinese calligraphy is a very special style of handwriting and direct character recognition is very difficult. Content-based keyword spotting is more feasible than recognition-based retrieval for calligraphy document.... Chinese calligraphy is a very special style of handwriting and direct character recognition is very difficult. Content-based keyword spotting is more feasible than recognition-based retrieval for calligraphy document. In this paper,we propose a novel Elastic Histogram of Oriented Gradient( EHOG) descriptor for calligraphy word spotting. The presented feature is a modification of Histogram of Oriented Gradient( HOG), widely used in human detection. In our approach,the input word image is partitioned into non-uniform rectangular cells according to the calligraphy character pixel intensity,and then in each cell a histogram of orientation is accumulated dynamically. Moreover,we adopt Derivative Dynamic Time Warping( DDTW) for image feature matching,which achieves good performance in gesture recognition. Experiments demonstrate a very significant improvement when comparing our proposed feature with previously developed ones,and also show DDTW produces superior alignments between two calligraphy character feature series than DTW. 展开更多
关键词 calligraphy word spotting Elastic HOG DDTW
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Review of micro-expression spotting and recognition in video sequences 被引量:1
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作者 Hang PAN Lun XIE +3 位作者 Zhiliang WANG Bin LIU Minghao YANG Jianhua TAO 《Virtual Reality & Intelligent Hardware》 2021年第1期1-17,共17页
Facial micro-expressions are short and imperceptible expressions that involuntarily reveal the true emotions that a person may be attempting to suppress,hide,disguise,or conceal.Such expressions can reflect a person&#... Facial micro-expressions are short and imperceptible expressions that involuntarily reveal the true emotions that a person may be attempting to suppress,hide,disguise,or conceal.Such expressions can reflect a person's real emotions and have a wide range of application in public safety and clinical diagnosis.The analysis of facial micro-expressions in video sequences through computer vision is still relatively recent.In this research,a comprehensive review on the topic of spotting and recognition used in micro expression analysis databases and methods,is conducted,and advanced technologies in this area are summarized.In addition,we discuss challenges that remain unresolved alongside future work to be completed in the field of micro-expression analysis. 展开更多
关键词 Facial expression Micro-expression spotting Micro-expression recognition DATABASE REVIEW
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Utilization of Hot Spotting to Identify Community Needs and Coordinate Care for High-Cost Patients in Memphis, TN
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作者 Teresa Cutts Edward Rafalski +1 位作者 Cori Grant Razvan Marinescu 《Journal of Geographic Information System》 2014年第1期23-29,共7页
In 2006, Methodist Le Bonheur Healthcare (MLH) created the Congregational Health Network (CHN, TM pending) which works closely with clergy in the most under-served zip codes of the city to improve access to care and o... In 2006, Methodist Le Bonheur Healthcare (MLH) created the Congregational Health Network (CHN, TM pending) which works closely with clergy in the most under-served zip codes of the city to improve access to care and overall health status of the population. To best coordinate CHN resources around high-utilization and address the largest health needs in the community, MLH applied hot spotting and geographic information system (GIS) spatial analysis techniques. These techniques were coupled with the community health needs assessment process at MLH and qualitative, participatory research findings captured in collaboration with church and other community partners. The methodology, which we call “participatory hot spotting,” is based upon the Camden Model, which leverages hot spotting to assess and prioritize community need in the provision of charity care, but adds a participatory, qualitative layer. In this study, spatial analysis was employed to evaluate hospital-based inpatient and outpatient utilization and define costs of charity care for the health system by area of residence. Ten zip codes accounted for 56% of total system charity care costs. Among these, the largest zip code, as defined by a percentage of total charity costs, contributed 18% of the inpatient utilization and 17% of the cost. Further, this zip code (38109) contributed 69% of the inpatient and 76% of the outpatient charity care volume and accounted for 75% of inpatient and 76% of outpatient charity care costs for the system. These findings were combined with grassroots intelligence that enabled a partnership with clergy and community members and Cigna Healthcare to better coordinate care in a place-based population health management strategy. Presentations of the analytics have subsequently been made to HHS and the CDC, referred to by some as the “Memphis Model”. 展开更多
关键词 Hot spotting CHNA (Community HEALTH Needs Assessment) Congregational HEALTH Network (CHN) MEMPHIS Model HEALTH DISPARITIES
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Effects of Poria cocos polysaccharide on growth performance,physiological parameters,and lipid metabolism of spotted sea bass Lateolabrax maculatus
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作者 Jing LU Zhangfan HUANG +2 位作者 Youling YE Anle XU Zhongbao LI 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第1期316-331,共16页
The aquaculture industry has developed significantly over the past few decades and has had a substantial impact on the global food supply and marine fisheries resources.However,some problems arise behind the scenes du... The aquaculture industry has developed significantly over the past few decades and has had a substantial impact on the global food supply and marine fisheries resources.However,some problems arise behind the scenes due to excessive intensive farming,such as slow animal growth,frequent disease,and lipid metabolism disorders.These problems have limited the sustainable development of the aquaculture industry,and a continuable solution is required.The use of fungal polysaccharide appears to provide a solution to these problems.Therefore,different supplemented levels of Poria cocos polysaccharide(PCP)(0,0.4,0.8,1.2,1.6,and 2.0 g/kg,respectively)were fed to spotted sea bass(Lateolabrax maculatus)in similar size(30.28±0.18 g)in current study.The effects of PCP on growth,physiological parameters,and lipid metabolism of spotted sea bass were investigated after a 4-week rearing period.Results showed,fish with PCP intake presented a significantly higher weight gain,specific growth rate,and a significantly lower feed conversion ratio.Significantly higher trypsin activity in liver and intestine were observed in fish with PCP intake.The superoxide dismutase activity in serum and liver of fish with PCP intake were significantly improved,while significantly higher serum total antioxidant capacity and hepatic catalase activity were also observed.However,no significant differences in lysozyme and alkaline phosphatase activity were evident among groups.Fish with PCP intake showed a significantly lower total cholesterol,but no noteworthy change in triglyceride and lipid-metabolismrelated genes expression were observed among groups.Results indicated that intake of PCP has a positive effect on growth and antioxidant capacity of spotted sea bass,but seems to have a limited effect on the non-specific immunity and lipid metabolism of spotted sea bass.Based on the regression analysis results,1.4 g/kg of PCP is the optimal dose for spotted sea bass in size(30.28±0.18 g). 展开更多
关键词 spotted sea bass Poria cocos POLYSACCHARIDE GROWTH lipid metabolism
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High-Efficiency Dynamic Scanning Strategy for Powder Bed Fusion by Controlling Temperature Field of the Heat-Affected Zone
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作者 Xiaokang Huang Xiaoyong Tian +5 位作者 Qi Zhong Shunwen He Cunbao Huo Yi Cao Zhiqiang Tong Dichen Li 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第1期203-214,共12页
Improvement of fabrication efficiency and part performance was the main challenge for the large-scale powder bed fusion(PBF)process.In this study,a dynamic monitoring and feedback system of powder bed temperature fiel... Improvement of fabrication efficiency and part performance was the main challenge for the large-scale powder bed fusion(PBF)process.In this study,a dynamic monitoring and feedback system of powder bed temperature field using an infrared thermal imager has been established and integrated into a four-laser PBF equipment with a working area of 2000 mm×2000 mm.The heat-affected zone(HAZ)temperature field has been controlled by adjusting the scanning speed dynamically.Simultaneously,the relationship among spot size,HAZ temperature,and part performance has been established.The fluctuation of the HAZ temperature in four-laser scanning areas was decreased from 30.85℃to 17.41℃.Thus,the consistency of the sintering performance of the produced large component has been improved.Based on the controllable temperature field,a dynamically adjusting strategy for laser spot size was proposed,by which the fabrication efficiency was improved up to 65.38%.The current research results were of great significance to the further industrial applications of large-scale PBF equipment. 展开更多
关键词 Powder bed fusion EFFICIENCY LARGE-SCALE Spot size Heat-affected zone(HAZ)
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Molecular Dynamics Simulation of Shock Response of CL-20 Co-crystals Containing Void Defects
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作者 Changlin Li Wei Yang +5 位作者 Qiang Gan Yajun Wang Lin Liang Wenbo Zhang Shuangfei Zhu Changgen Feng 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期364-374,共11页
To investigate the effect of void defects on the shock response of hexanitrohexaazaisowurtzitane(CL-20)co-crystals,shock responses of CL-20 co-crystals with energetic materials ligands trinitrotoluene(TNT),1,3-dinitro... To investigate the effect of void defects on the shock response of hexanitrohexaazaisowurtzitane(CL-20)co-crystals,shock responses of CL-20 co-crystals with energetic materials ligands trinitrotoluene(TNT),1,3-dinitrobenzene(DNB),solvents ligands dimethyl carbonate(DMC) and gamma-butyrolactone(GBL)with void were simulated,using molecular dynamics method and reactive force field.It is found that the CL-20 co-crystals with void defects will form hot spots when impacted,significantly affecting the decomposition of molecules around the void.The degree of molecular fragmentation is relatively low under the reflection velocity of 2 km/s,and the main reactions are the formation of dimer and the shedding of nitro groups.The existence of voids reduces the safety of CL-20 co-crystals,which induced the sensitivity of energetic co-crystals CL-20/TNT and CL-20/DNB to increase more significantly.Detonation has occurred under the reflection velocity of 4 km/s,energetic co-crystals are easier to polymerize than solvent co-crystals,and are not obviously affected by voids.The results show that the energy of the wave decreases after sweeping over the void,which reduces the chemical reaction frequency downstream of the void and affects the detonation performance,especially the solvent co-crystals. 展开更多
关键词 CL-20 co-crystals Molecular dynamics simulation Reactive forcefield Impact response Hot spot Void defect
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Overexpression of auxin/indole-3-acetic acid gene MdIAA24 enhances Glomerella leaf spot resistance in apple(Malus domestica)
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作者 Qian Wang Dong Huang +2 位作者 Wenyan Tu Fengwang Ma Changhai Liu 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第1期15-24,共10页
Auxin is throughout the entire life process of plants and is involved in the crosstalk with other hormones,yet its role in apple disease resistance remains unclear.In this study,we investigated the function of auxin/i... Auxin is throughout the entire life process of plants and is involved in the crosstalk with other hormones,yet its role in apple disease resistance remains unclear.In this study,we investigated the function of auxin/indole-3-acetic acid(IAA)gene Md IAA24 overexpression in enhancing apple resistance to Glomerella leaf spot(GLS)caused by Colletotrichum fructicola(Cf).Analysis revealed that,upon Cf infection,35S::Md IAA24 plants exhibited enhanced superoxide dismutase(SOD)and peroxidase(POD)activity,as well as a greater amount of glutathione(reduced form)and ascorbic acid accumulation,resulting in less H_(2)O_(2)and superoxide anion(O_(2)^(-))in apple leaves.Furthermore,35S::Md IAA24 plants produced more protocatechuic acid,proanthocyanidins B1,proanthocyanidins B2 and chlorogenic acid when infected with Cf.Following Cf infection,35S::Md IAA24 plants presented lower levels of IAA and jasmonic acid(JA),but higher levels of salicylic acid(SA),along with the expression of related genes.The overexpression of Md IAA24 was observed to enhance the activity of chitinase andβ-1,3-glucanase in Cfinfected leaves.The results indicated the ability of Md IAA24 to regulate the crosstalk between IAA,JA and SA,and to improve reactive oxygen species(ROS)scavenging and defense-related enzymes activity.This jointly contributed to GLS resistance in apple. 展开更多
关键词 APPLE MdIAA24 Glomerella leaf spot(GLS) Antioxidant capacity AUXIN Salicylic acid Jasmonic acid
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Effect of casting process on the inner-wall band segregation of high-strength antisulfur pipes
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作者 LUO Ming ZHANG Zhonghua 《Baosteel Technical Research》 CAS 2024年第1期27-36,共10页
Controlling inner-wall band segregation is one of the difficulties in the production of high-strength antisulfur pipes.Comparative tests were carried out on different casting processes(superheat,mold electromagnetic s... Controlling inner-wall band segregation is one of the difficulties in the production of high-strength antisulfur pipes.Comparative tests were carried out on different casting processes(superheat,mold electromagnetic stirring,end electromagnetic stirring,casting speed and soft reduction)for the smelting of high-strength antisulfur pipes.The microstructures of continuous-casting billets and hot-rolled or tempered pipes were analyzed using a metallographic microscope and scanning electron microscope.The mechanism and evolution law regarding the inner-wall band segregation of high-strength antisulfur pipes were studied,and the influence of different casting processes was explored. 展开更多
关键词 high strength antisulfur pipe casting process spot segregation band segregation
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Design of Fully Automatic Specification Selection System for Resistance Welding Equipment
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作者 Xiangkun Lu Zengtai Tian +1 位作者 Hao Xu Yue Guo 《Journal of Harbin Institute of Technology(New Series)》 CAS 2024年第1期64-68,共5页
A system for fully automatic selection of welding specifications in resistance welding equipment has been developed to address the problem of workers frequently choosing the wrong specifications during manual welding ... A system for fully automatic selection of welding specifications in resistance welding equipment has been developed to address the problem of workers frequently choosing the wrong specifications during manual welding of multiple parts on a single machine in automobile factories. The system incorporates an automatic recognition system for different workpiece materials using the added machine fixture,visual detection system for nuts and bolts,and secondary graphical confirmation to ensure the correctness of specification calling. This system achieves reliable,fully automatic selection of welding specifications in resistance welding equipment and has shown significant effects in improving welding quality for massproduced workpieces,while solving the problem of specification calling errors that can occur with traditional methods involving process charts and code adjustments. This system is particularly suitable for promoting applications in manual welding of multiple parts on a single machine in automobile factories,ensuring correct specification calling and welding quality. 展开更多
关键词 seat spot welding welding specifications fully automatic
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Genomic Selection for Frogeye Leaf Spot Resistance in Soybean
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作者 Yao Lanning Chen Yizhi +4 位作者 Li Haochen Zhang Yue Xia Mingyu Ning Shicheng Ning Hailong 《Journal of Northeast Agricultural University(English Edition)》 CAS 2024年第1期11-19,共9页
Soybean frogeye leaf spot(FLS) disease is a global disease affecting soybean yield, especially in the soybean growing area of Heilongjiang Province. In order to realize genomic selection breeding for FLS resistance of... Soybean frogeye leaf spot(FLS) disease is a global disease affecting soybean yield, especially in the soybean growing area of Heilongjiang Province. In order to realize genomic selection breeding for FLS resistance of soybean, least absolute shrinkage and selection operator(LASSO) regression and stepwise regression were combined, and a genomic selection model was established for 40 002 SNP markers covering soybean genome and relative lesion area of soybean FLS. As a result, 68 molecular markers controlling soybean FLS were detected accurately, and the phenotypic contribution rate of these markers reached 82.45%. In this study, a model was established, which could be used directly to evaluate the resistance of soybean FLS and to select excellent offspring. This research method could also provide ideas and methods for other plants to breeding in disease resistance. 展开更多
关键词 LASSO regression stepwise regression genomic selection model SOYBEAN frogeye leaf spot(FLS)disease
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济南市庆祝中国共产党成立100周年大型文艺演出灯光舞美设计实施
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作者 王琨 张良学 孙康 《照明工程学报》 2024年第2期131-140,共10页
本文详细介绍了济南市庆祝中国共产党成立100周年大型文艺演出灯光舞美设计思路、设计方案、设计特点及艺术处理。舞台集独唱、合唱、话剧、舞蹈、戏曲、杂技等多种艺术形式于一体,融合了声、光、电、虚拟植入等技术手段,呈现出一幅建... 本文详细介绍了济南市庆祝中国共产党成立100周年大型文艺演出灯光舞美设计思路、设计方案、设计特点及艺术处理。舞台集独唱、合唱、话剧、舞蹈、戏曲、杂技等多种艺术形式于一体,融合了声、光、电、虚拟植入等技术手段,呈现出一幅建党百年,波澜壮阔的历史画卷。 展开更多
关键词 建党100周年 灯光舞美设计 LED光源spot切割灯 光束灯 LED染色灯 高色温
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Development and Quality Improvement of Lianqingshan Scenic Spot in Tengzhou City
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作者 ZHANG Dongmei WANG Yifan 《Journal of Landscape Research》 2024年第1期91-95,共5页
Since the 21st century,China’s overall national strength has increased continuously.With the rapid development of the tourism industry,people have an increasingly strong demand for travel.Firstly,tourists’satisfacti... Since the 21st century,China’s overall national strength has increased continuously.With the rapid development of the tourism industry,people have an increasingly strong demand for travel.Firstly,tourists’satisfaction to Lianqingshan Scenic Spot was surveyed,and then the types of tourism resources,current development situation and problems in the scenic spot were analyzed.Finally,some countermeasures and suggestions for its development and quality improvement were put forward.It is found that based on the environmental quality,safety and service quality of Lianqingshan Scenic Spot,the basic situation of the development of the scenic spot was investigated,and the comprehensive satisfaction of each item is 3.30,3.24 and 3.32.The tourists of the scenic spot is mainly from Tengzhou City and its surrounding cities,and the popularity of the scenic spot is relatively low.The management personnel of the scenic spot needs to increase the tourist flow by improving its exposure.The problems of the scenic spot include low popularity,poor environmental quality,low safety of tourists,poor operating condition of catering industry and service quality of service personnel. 展开更多
关键词 Lianqingshan Scenic Spot PROBLEMS COUNTERMEASURES
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Seasonal Abundance and Diversity of Birds of Prey and Owls in Al Wathba Wetland Reserve in Abu Dhabi, UAE
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作者 Shakeel Ahmed Salim Jáved +3 位作者 Shahid B. Khan Eissa Al Hammadi Abdullah Al Hammadi Nouf Sameer Alqadi 《Open Journal of Ecology》 2024年第3期228-244,共17页
Inland wetlands in Abu Dhabi Emirate are wintering and stopover sites for migratory birds of prey. We conducted long-term regular monitoring surveys in Al Wathba Wetland Reserve (AWWR) from January 1995 to December 20... Inland wetlands in Abu Dhabi Emirate are wintering and stopover sites for migratory birds of prey. We conducted long-term regular monitoring surveys in Al Wathba Wetland Reserve (AWWR) from January 1995 to December 2022. Both diurnal and occasionally nocturnal surveys were undertaken to record the migratory raptors and owls in the Wetland Reserve. During the study, a total of 1282 regular monitoring visits were undertaken and 27 species of diurnal raptors and owls representing five families and three orders were detected. These represent 57% of the total species of birds of prey recorded in the UAE. Overall, 63% of all the species that we observed were Accipitriformes followed by 26% Falconiformes and 11% Strigiformes. We found that changes in mean daily temperature have a positive effect on raptor species diversity and abundance in the Wetland Reserve. The species encounter rate was higher in low temperature as compared to high temperature and overall regression equation was statistically significant F (4, 1126) = 8.49), p = 0.00). However, the numbers of raptors did not vary significantly across the years (p = 0.51). Western Marsh-harrier (Circus aeruginosus) and Greater Spotted Eagle (Clanga clanga) were recorded to be the most abundant species in the wetland reserve followed by Common Kestrel (Falco tinnunculus). However, the encounter rate of globally threatened Greater Spotted Eagle was detected to have significantly decreased since 2016. Moreover, 63% of the species detected were uncommon and rarely recorded such as 1) Saker Falcon 2) Lanner Falcon 3) Long-eared Owl & Merlin, which were the rare records from the wetland reserve. Furthermore, 27 years of regular monitoring in the wetland have yielded diverse diurnal raptors and owl fauna (H) = 0.83, (E) = 1.43 (Shannon Diversity Index). The results demonstrate that long-term monitoring surveys in arid environments are essential to determine the trends in the raptor populations and to document rare and globally important species. 展开更多
关键词 Wetland Reserve RAPTORS Abundance DIVERSITY Abu Dhabi Inland Wetland AWWR Greater Spotted Eagle
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Oral Hygiene in the Presence of Orthodontic Therapy
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作者 Emmanuel John Aryeetey Hicham Benyahia Fatima Zaoui 《Journal of Biosciences and Medicines》 2024年第2期98-110,共13页
Orthodontic treatment offers great advantages in improving facial and smile aesthetics, self-confidence and the function of the stomatognathic apparatus. The pursuit of these advantages makes use of orthodontic applia... Orthodontic treatment offers great advantages in improving facial and smile aesthetics, self-confidence and the function of the stomatognathic apparatus. The pursuit of these advantages makes use of orthodontic appliances that could be fixed or removable. However, it’s worth stating that these appliances interfere with tooth brushing, making it more difficult to brush teeth effectively. Orthodontics appliances therefore promote the accumulation of dental plaque, which results in both quantitative and qualitative changes in the oral microbiota, hence, exposing patients to several adverse effects such as White spot lesions, dental caries, periodontal pathologies and halitosis. For this reason, oral assessment of patients before, during and after treatment is necessary as well as oral hygiene instructions and motivation. Orthodontists therefore, should educate patients on oral and periodontal hygiene in order to control dental and periodontal complications. Prescriptions of plaque control materials adapted to each patient are done in order to optimize the final result and minimize unwanted complications. 展开更多
关键词 Orthodontic Treatment Oral Microbiome Oral Hygiene PERIODONTITIS GINGIVITIS Orthodontic Fixed Appliances Orthodontic Removable Appliances White Spot Lesions (WSL)
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Inter-Row Spacing of PV Power Plant
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作者 Laiqat Ali Khan 《Energy and Power Engineering》 2024年第3期121-129,共9页
When designing a solar power plant, it is much more important to avoid the shadow on the PV Panels. As the shadow falls on the PV Panels;it significantly reduces the generation of required power as planned and designe... When designing a solar power plant, it is much more important to avoid the shadow on the PV Panels. As the shadow falls on the PV Panels;it significantly reduces the generation of required power as planned and designed. This research paper and case study will help a lot to avoid shadow, especially when selecting inter-row spacing between the strings of solar power plants. 展开更多
关键词 Inter Row Spacing Shadow Effect on PV Plant Hot Spot Heating
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Investigation of the Clinical Diagnostic Significance of the T-Cell Test for Tuberculosis combined with Erythrocyte Sedimentation Test in Pulmonary Tuberculosis
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作者 Jialong Wang 《Journal of Clinical and Nursing Research》 2024年第3期55-60,共6页
Objective:To investigate the clinical diagnostic significance of peripheral blood T-cell test(T-spot test)for tuberculosis(TB)infection combined with erythrocyte sedimentation rate(ESR)in pulmonary TB.Methods:41 patie... Objective:To investigate the clinical diagnostic significance of peripheral blood T-cell test(T-spot test)for tuberculosis(TB)infection combined with erythrocyte sedimentation rate(ESR)in pulmonary TB.Methods:41 patients with a clinical diagnosis of TB during hospitalization from January 2020 to April 2023 in our hospital were selected as the experimental group,and 45 patients without TB(bronchopneumonia patients)were selected as the control group.The diagnostic specificity,sensitivity,and accuracy of the T-spot TB test,ESR test,and the combined test of the two were calculated respectively.Results:The sensitivity,specificity,and accuracy of the T-spot TB test combined with ESR for the diagnosis of TB in the experimental group were significantly higher than the individual results of the T-spot TB test and ESR test alone(P<0.05).Conclusion:The T-spot TB test combined with the ESR test for TB diagnosis has greater clinical value than carrying out the tests individually. 展开更多
关键词 Peripheral blood tuberculosis infection T-cell spot test Erythrocyte sedimentation rate test TUBERCULOSIS Clinical diagnosis
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1999-2019年西南喀斯特地区NDVI时空变化及其气候驱动 被引量:1
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作者 靖娟利 邓棋方 +2 位作者 和彩霞 王永锋 马炳鑫 《水土保持研究》 CSCD 北大核心 2023年第3期232-239,共8页
[目的]西南喀斯特地区生态环境脆弱,对其植被覆盖变化及气候驱动机制进行研究具有重要意义。[方法]基于1999-2019年SPOT NDVI数据和同期209个气象站点的气温和降水数据,采用Theil-Sen+Mann-Kendall趋势分析法、偏相关分析和复相关分析法... [目的]西南喀斯特地区生态环境脆弱,对其植被覆盖变化及气候驱动机制进行研究具有重要意义。[方法]基于1999-2019年SPOT NDVI数据和同期209个气象站点的气温和降水数据,采用Theil-Sen+Mann-Kendall趋势分析法、偏相关分析和复相关分析法,探讨西南喀斯特地区NDVI时空变化及其气候驱动。[结果]1999-2019年西南喀斯特地区NDVI呈显著上升趋势,整体植被覆盖较好;NDVI变化主要以极显著上升趋势为主,仅5.73%的地区呈退化趋势。NDVI与气温和降水整体上均呈正偏相关关系,气温对NDVI的影响强于降水,且存在空间差异性。NDVI与气温和降水的复相关显著性通过0.05,0.01水平的面积分别占15.12%,5.68%;NDVI主要受气温驱动,占研究区面积的13.90%,其他气候因子驱动类型占比均未超过3%。[结论]揭示了西南喀斯特地区植被覆盖的时空变化特征,明确了气候因子对植被覆盖变化的驱动机制。 展开更多
关键词 西南喀斯特地区 SPOT NDVI 趋势分析 M-K检验 偏相关系数
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通过教学反思促进教师专业发展——美国大学STEM课堂观察工具SPOT研究及启示
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作者 高巍 杨雪 《教师教育论坛》 2023年第7期65-74,83,共11页
SPOT(Student Participation Observation Tool)是美国加利福利亚州的圣何塞州立大学发布的大学STEM课堂观察工具,用于评价大学STEM课堂上教师促进学生主动学习的教学行为及其质量。为了验证该观察工具的有效性,工具开发者针对五所大学... SPOT(Student Participation Observation Tool)是美国加利福利亚州的圣何塞州立大学发布的大学STEM课堂观察工具,用于评价大学STEM课堂上教师促进学生主动学习的教学行为及其质量。为了验证该观察工具的有效性,工具开发者针对五所大学的STEM课堂举办了一个系列的研讨会,结果显示:SPOT可以促使教师反思他们的教学方法和课堂上的学生活动,而不是课程内容或课程组织形式,教师能够使用SPOT观察课堂教学并获得可靠的数据,以反思和改变他们的课堂实践,进而实现自身的专业发展。基于对SPOT的阐释与研究,我国大学教学尤其要从如何促进教师专业发展的角度,关注师生的课堂参与行为,促进教师的教学反思。 展开更多
关键词 专业发展 SPOT观察工具 大学STEM课堂
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An insight on the mechanism of efficient leaching of vanadium from vanadium shale induced by microwave-generated hot spots 被引量:2
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作者 Sheng Li Yimin Zhang +1 位作者 Yizhong Yuan Pengcheng Hu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第2期293-302,共10页
Microwave heating can rapidly and uniformly raise the temperature and accelerate the reaction rate.In this paper,microwave heating was used to improve the acid leaching,and the mechanism was investigated via microscop... Microwave heating can rapidly and uniformly raise the temperature and accelerate the reaction rate.In this paper,microwave heating was used to improve the acid leaching,and the mechanism was investigated via microscopic morphology analysis and numerical simulation by COMSOL Multiphysics software.The effects of the microwave power,leaching temperature,CaF_(2) dosage,H_(2)SO_(4) concentration,and leaching time on the vanadium recovery were investigated.A vanadium recovery of 80.66%is obtained at a microwave power of 550 W,leaching temperature of 95℃,CaF_(2) dosage of 5wt%,H_(2)SO_(4) concentration of 20vol%,and leaching time of 2.5 h.Compared with conventional leaching technology,the vanadium recovery increases by 6.18%,and the leaching time shortens by 79.17%.More obvious pulverization of shale particles and delamination of mica minerals happen in the microwave-assisted leaching process.Numerical simulation results show that the temperature of vanadium shales increases with an increase in electric field(E-field).The distributions of E-field and temperature among vanadium shale particles are relatively uniform,except for the higher content at the contact position of the particles.The analysis results of scaleup experiments and leaching experiments indicate high-temperature hot spots in the process of microwave-assisted leaching,and the local high temperature destroys the mineral structure and accelerates the reaction rate. 展开更多
关键词 vanadium shale microwave-assisted leaching hot spots numerical simulation
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Spatial and temporal analysis of urban heat island effect over Tiruchirappalli city using geospatial techniques 被引量:2
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作者 Ajay Badugu K.S.Arunab +1 位作者 Aneesh Mathew P.Sarwesh 《Geodesy and Geodynamics》 EI CSCD 2023年第3期275-291,共17页
Alterations made to the natural ground surface and the anthropogenic activity elevate the surface and air temperature in the urban areas compared with the surrounding rural areas,known as urban heat island effect.Ther... Alterations made to the natural ground surface and the anthropogenic activity elevate the surface and air temperature in the urban areas compared with the surrounding rural areas,known as urban heat island effect.Thermal remote sensors measure the radiation emitted by ground objects,which can be used to estimate the land surface temperature and are beneficial for studying urban heat island effects.The present study investigates the spatial and temporal variations in the effects of urban heat island over Tiruchirappalli city in India during the summer and winter seasons.The study also identifies hot spots and cold spots within the study area.In this study,a significant land surface temperature difference was observed between the urban and rural areas,predominantly at night,indicating the presence of urban heat island at night.These diurnal land surface temperature fluctuations are also detected seasonally,with a relatively higher temperature intensity during the summer.The trend line analysis shows that the mean land surface temperature of the study area is increasing at a rate of 0.166 K/decade with p less than 0.01.By using the spatial autocorrelation method with the urban heat island index as the key parameter,hot spots with a 99 percent confidence level and a 95 percent confidence level were found within the urban area.A hot spot with 95 and 90 percent confidence level was identified outside the urban area.This spike in temperature for a particular region in the rural area is due to industry and the associated built-up area.The study also identified cold spots with a 90 percent confidence level within the rural area.However,cold spots with a 95 and 99 percent confidence level were not identified within the study area. 展开更多
关键词 URBANIZATION Land surface temperature Urban heat island effect Hot spots Remote sensing
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