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Identifying drivers of urban landuse changes in the Wenchuan earthquake- affected area by using night-time light data
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作者 HUANG Tao DING Mingtao +2 位作者 GENG Dongxian GAO Zemin ZHENG Hao 《Journal of Mountain Science》 SCIE CSCD 2024年第4期1140-1159,共20页
To learn the process of urban land evolution before and after an earthquake is vital to formulate the urban reconstruction control policies and recovery measures in the earthquake-stricken areas.However,spatiotemporal... To learn the process of urban land evolution before and after an earthquake is vital to formulate the urban reconstruction control policies and recovery measures in the earthquake-stricken areas.However,spatiotemporal evolution and its driving factors of urban land in earthquake-prone areas remains limited due to the scarcity of ground observation data.This research,leveraging night-time light remote sensing imagery and land cover data,conducted a comprehensive analysis of the long-term evolution characteristics of urban land in earthquake-prone areas.It introduced methodologies for assessing the socio-economic impact and the primary natural environmental factors driving urban land evolution in these regions.To validate the proposed methods,the 2008 Wenchuan earthquake-affected area in China was selected as a representative study area.The results indicated that the average Digital Number(DN)values in socio-economically impacted areas showed a trend of rising,falling,and then rising again after the earthquake.DN values in three types of damaged areas including Type Ⅱ,Type Ⅲ,and Type Ⅳ exceeded pre-earthquake levels.The analysis of determinative factors influencing urban land evolution revealed that slope and elevation were key elements in controlling urban land expansion before the earthquake,whereas factors such as slope,elevation,lithology,and faults had a stronger influence on urban land expansion after the earthquake.It can be seen that,in view of the differences in the natural conditions of regions for post-disaster reconstruction,the local government need to actively adjust and adapt to urban spatial planning,so as to leverage the scale effect of large-scale inputs of funds,facilities,human resources and other factors after the disaster,thus enhancing resilience and recovery efficiency in response to disaster impacts. 展开更多
关键词 Wenchuan earthquake night-time lights Urban land Post-earthquake reconstruction
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Spatio-temporal variation and propagation direction of coal fire in Jharia Coalfield,India by satellite-based multi-temporal night-time land surface temperature imaging 被引量:4
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作者 Narendra Singh R.S.Chatterjee +1 位作者 Dheeraj Kumar D.C.Panigrahi 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2021年第5期765-778,共14页
In this paper,the spatio-temporal variation and propagation direction of coal fire were studied in the Jharia Coalfield(JCF),India during 2006–2015 through satellite-based night-time land surface temperature(LST)imag... In this paper,the spatio-temporal variation and propagation direction of coal fire were studied in the Jharia Coalfield(JCF),India during 2006–2015 through satellite-based night-time land surface temperature(LST)imaging.The LST was retrieved from Advanced Spaceborne Thermal Emission and Reflection Radiometer(ASTER)night-time thermal-infrared data by a robust split-window algorithm based on scene-specific regression coefficients,band-specific hybrid emissivity,and night-time atmospheric transmittance.The LST-profile-based coal fire detection algorithm was formulated through statistical analysis of the LST values along multiple transects across diverse coal fire locations in the JCF in order to compute date-specific threshold temperatures for separating thermally-anomalous and background pixels.This algorithm efficiently separates surface fire,subsurface fire,and thermally-anomalous transitional pixels.During the observation period,it was noticed that the coal fire area increased significantly,which resulted from new coal fire at many places owing to extensive opencast-mining operations.It was observed that the fire propagation occurred primarily along the dip direction of the coal seams.At places,lateral-propagation of limited spatial extent was also observed along the strike direction possibly due to spatial continuity of the coal seams along strike.Moreover,the opencast-mining activities carried out during 2009–2015 and the structurally weak planes facilitated the fire propagation. 展开更多
关键词 Satellite-based night-time imaging Land surface temperature Coal fire Spatio-temporal variation Propagation direction Jharia Coalfield
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The CCD instrument background of the SMILE SXI 被引量:2
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作者 M.W.J.Hubbard O.Hetherington +6 位作者 D.J.Hall T.W.Buggey S.Parsons T.Arnold A.Holland C.Pagani S.Sembay 《Earth and Planetary Physics》 EI CSCD 2024年第1期15-24,共10页
The ESA and CAS SMILE mission orbit is highly elliptical and will pass through multiple radiation environments.The Soft X-ray Imager(SXI)instrument aboard has a radiation shutter door designed to close when the surrou... The ESA and CAS SMILE mission orbit is highly elliptical and will pass through multiple radiation environments.The Soft X-ray Imager(SXI)instrument aboard has a radiation shutter door designed to close when the surrounding radiation flux is high.The shutter door will close when passing below an altitude threshold to protect against trapped particles in the Earth’s Van Allen Belts.Therefore,two radiation environments can be approximated based on the shutter door position:open and closed.The instrument background for the CCDs(Charge-Coupled Devices)that form the focal plane array of the SXI were evaluated for the two environments.Due to the correlation of the space environment with the solar cycle,the solar minima and maxima,the background was also evaluated at these two extremes.The results demonstrated that the highest instrument background will occur during solar minima due to the main contributing source being Galactic Cosmic Rays(GCRs).It was also found that the open background was highest for solar minima and that the closed background was highest during solar maxima.This is due to the radiation shutter door acting as a scattering centre and the changes in the energy flux distribution of the GCRs between the two solar extremes. 展开更多
关键词 instrument background X-ray astronomy space radiation
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Glaucoma surgery experiments using digital microscope-integrated optical coherence tomography and OCT-compatible instruments 被引量:1
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作者 Tianliang Jiang Jinyu Fan +2 位作者 Ning Tang Yi He Guohua Shi 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2024年第5期105-113,共9页
There is a certain failure rate in traditional glaucoma surgery because of the lack of depth information in microscope images.In this work,we present a digital microscope-integrated optical coherence tomography(MIOCT)... There is a certain failure rate in traditional glaucoma surgery because of the lack of depth information in microscope images.In this work,we present a digital microscope-integrated optical coherence tomography(MIOCT)system and several custom-made OCT-compatible instruments for glaucoma surgery.Sixteen ophthalmologists were asked to perform trabeculectomy and canaloplasty on live porcine eyes using the system and instruments.After surgery,a subjective feedback survey about the user experience was taken.The experiment results showed that our system can help surgeons easily locate important tissue structures during surgery.The custom-made instruments also solved the shadowing problem in OCT imaging.Surgeons preferred to use the system in their future practice. 展开更多
关键词 Microscope-integrated optical coherence tomography OCT-compatible instruments glaucoma surgery TRABECULECTOMY CANALOPLASTY
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Dialect Diversity,Factor Agglomeration and City Size:Empirical Test Based on Satellite Night-Time Light Data
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作者 Ding Congming Huang Xueyang Zhou Min 《China Economist》 2021年第4期115-130,共16页
Since the reform and opening up program was initiated in 1978,China’s urbanization has made rapid progress,but urban development remains unbalanced and insufficient.From the perspective of social and cultural diversi... Since the reform and opening up program was initiated in 1978,China’s urbanization has made rapid progress,but urban development remains unbalanced and insufficient.From the perspective of social and cultural diversity,this paper explores the impact of dialect diversity on city size.Dialect diversity impedes the expansion of cities by causing a trust segmentation and impeding cross-regional factor flow and the factor agglomeration effect.Based on the regional dialect diversity indicator and the NPP-VIIRS city night-time light index of 2016,this paper offers an empirical study of the impact of dialect diversity on city size.Econometric results indicate that dialect diversity has a significantly negative impact on city size.On average,an increase of each dialect sub-category leads to a decrease in city size estimated by the night-time light index by 4.55%.Robustness test and causality identification reveal that the estimated results of this paper have a robust causal relationship.Further empirical research indicates that dialect diversity affects the expansion of city size by inhibiting the flow and agglomeration of labor,capital and technology factors.Our research suggests that the development of diverse and inclusive modern cities needs to balance the costs and benefits of cultural diversity and uniformity,break through cultural barriers,remove cultural prejudices,raise the level of social trust,and give play to the complementary effect of cultural diversity. 展开更多
关键词 dialect diversity city size night-time light index
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Significant Shift of Ambient Night-Time Air Temperature during Rice Growing Season in Major US Rice States
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作者 Kharla Mendez M. Arlene Adviento-Borbe +1 位作者 Argelia Lorence Harkamal Walia 《American Journal of Climate Change》 2021年第1期134-151,共18页
Heat stress studies in rice (<em>Oryza sativa</em> sp.) under extreme weather scenarios generally use constant temperatures to influence the crop responses without relation to actual weather changes. These... Heat stress studies in rice (<em>Oryza sativa</em> sp.) under extreme weather scenarios generally use constant temperatures to influence the crop responses without relation to actual weather changes. These heat stress studies may have limited implications for future crop yields because elevated temperatures are not based on local temperature fluctuations. This study investigated the night-time air temperature pattern and assessed the status and reliability of available weather station data in four major rice growing states;Arkansas (AR), California (CA), Louisiana (LA) and Texas (TX) using four public weather station databases. Hourly and daily night-time air temperatures from 20:00 to 06:00 were obtained from 1940 to 2018 during the rice growing period. During the 67-year period, a significant increase of 1.12<span style="white-space:nowrap;">&#176;</span>C and 0.53<span style="white-space:nowrap;">&#176;</span>C in seasonal night air temperature occurred in CA and AR (<em>P</em> ≤ 0.001) while LA and TX showed minimal to no increase in night air temperature. Across all rice states and years, night air temperature fluctuations ranged between ±0.2<span style="white-space:nowrap;">&#176;</span>C and ±4<span style="white-space:nowrap;">&#176;</span>C with the greatest occurred in CA (2.9<span style="white-space:nowrap;">&#176;</span>C) and AR (4.5<span style="white-space:nowrap;">&#176;</span>C). Mean night-time air temperature across all states ranged from 22.6<span style="white-space:nowrap;">&#176;</span>C to 29.5<span style="white-space:nowrap;">&#176;</span>C with a rate of increase of 0.01<span style="white-space:nowrap;">&#176;</span>C to 0.02<span style="white-space:nowrap;">&#176;</span>C per year since 1941. Due to a relatively smaller spatial dataset (from 1941-2018), trend analyses for AR, TX and LA showed modest bias with root mean square errors (RMSE) of 0.5<span style="white-space:nowrap;">&#176;</span>C to 1.1<span style="white-space:nowrap;">&#176;</span>C of absolute mean temperature across all locations. Results in this study showed seasonal night-time air temperature change occurred in some major US rice producing states during the last 67-years. This study highlights the need for more weather stations near agricultural farms to reliably derive actual temperature patterns in the rice growing regions. 展开更多
关键词 night-time Air Temperature RICE Climate Variability Weather Database US Rice States
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Night-time Rise in Rat Pineal N-Acetyltransferase due to Carbaryl Administration Is Reduced by Propranolol Treatment
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作者 AHMED M. ATTIA MOSTAFA H. MOSTAFA +2 位作者 BRUCE A. RICHARDSON AND RUSSEL J. REITER(Department of Environmental Studies, Institute of Graduate Studies and Research, P.O.Box 832, Alexandria, Egypt Department of Cellular and Structural Biology, University of Texas, 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1995年第1期45-53,共9页
The purpose of the present study was to examine the effects of administration of sublethal doses of carbaryl on nighttime rat pineal melatonin synthesis in the presence and absence of propranolol, a β-adrenergic rece... The purpose of the present study was to examine the effects of administration of sublethal doses of carbaryl on nighttime rat pineal melatonin synthesis in the presence and absence of propranolol, a β-adrenergic receptor antagonist. Two groups of adult male albino rats were administered orally N-methyl-l-naphthylcarbamate (carbaryl) (8. 33mg/kg BW daily in corn oil) for six successive days; another two groups received corn oil only.On the last day of carbaryl treatment, half of the animals received an intraperitoneal injection of propranolol (20 mg/kg body weight, one hour before lights off). The other two groups were given a saline injection. Four hours after darkness onset, pineal N-acetyltransferase (NAT) and hydroxyindole-O-methyltransferase (HIOMT) activities as well as pineal concentrations of 5-hydroxytryptophan (5HTP), serotonin (5HT),5-hydroxyindole acetic acid (5HIAA) and pineal and serum melatonin levels were measured. Nocturnal NAT activity was increased due to carbaryl administration but the pesticide was ineffective in stimulating NAT activity in rats treated with propranolol.Pineal 5HT was decreased due to carbaryl administration but 5HTP and 5HIAA levels were unaffected. Pineal and serum melatonin levels were decreased due to propranolol treatment. The results indicate that carbaryl may influence pineal NAT activity by a mechanism that involves β-adrenergic neural transmission. 展开更多
关键词 TIME night-time Rise in Rat Pineal N-Acetyltransferase due to Carbaryl Administration Is Reduced by Propranolol Treatment
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Electromagnetic response function for the semi-annual variations estimated by the single-station method using the night-time values of the geomagnetic fields
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作者 陈伯舫 《Acta Seismologica Sinica(English Edition)》 CSCD 2000年第3期316-324,共9页
The geomagnetic night-time values were used to estimate the electromagnetic response function Q1 for half-year period. If the spatial structure of the source field can be described by the approximation, one can estim... The geomagnetic night-time values were used to estimate the electromagnetic response function Q1 for half-year period. If the spatial structure of the source field can be described by the approximation, one can estimate the Q1 value using the single-station Z/H method. This technique enables us to carry out regional deep gcomagnetic sounding by the method. The data used for analyses are geomagnetic night-time values for about, typically, 26 years from 5 good-quality stations and for several years from 34 stations distributed over the globe. The results indicate that the night-time values yield more reliable response estimates for half-year period compared to the usual estimates obtained from daily means. It implies that the approximation for the night-time fields holds good for the half-year period, but the daily means are not suitable for estimating the response function of the semi-annual variations by using the single-station method. Source field analyses for daily means data and night-time means data have also been carried out in this paper. 展开更多
关键词 geomagnetic night-time data semi-annual variations electromagnetic response functions single-station Z/H method
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Special topic on new instruments and sensing technologies
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作者 Qi Xiao Yong Yang 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2024年第4期I0001-I0001,共1页
New instruments and sensing technologies have extensive applications in non-destructive testing,safety monitoring,human-computer interaction,precision sensing,and other fields.The emergence of new structural materials... New instruments and sensing technologies have extensive applications in non-destructive testing,safety monitoring,human-computer interaction,precision sensing,and other fields.The emergence of new structural materials,new preparation processes,and new sensing theories has driven the development of precision measurement instruments and intelligent sensing technology with the rapid development of electromagnetics,optics,and materials science. 展开更多
关键词 COMPUTER instrumentS OPTICS
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Exploring the Mysteries of the Universe, and Innovation Leading the Future——Astronomical Techniques and Instruments
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《Astronomical Techniques and Instruments》 CSCD 2024年第1期I0001-I0001,共1页
Dear Readers:Astronomical Techniques and Instruments is a professional English journal of open access devoted to recent develop-ments,discoveries,and theories in astronomical techniques,methods,and instruments.It will... Dear Readers:Astronomical Techniques and Instruments is a professional English journal of open access devoted to recent develop-ments,discoveries,and theories in astronomical techniques,methods,and instruments.It will serve as a platform for dis-course,learning,and information sharing for astronomic and astrophysics professionals worldwide. 展开更多
关键词 JOURNAL devoted instrumentS
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Reform of Teaching Practice of Modern Instrumental Analysis in Biotechnology Programs
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作者 Kun TANG Tong LIN +3 位作者 Zhenxia SHI Jie QIAO Chunyan XIE Lixin DU 《Agricultural Biotechnology》 2024年第3期93-95,共3页
Through the online and offline practical reform of the Modern Instrumental Analysis course of biotechnology majors from teaching content,teaching method,teaching demonstration to teaching effect,the traditional single... Through the online and offline practical reform of the Modern Instrumental Analysis course of biotechnology majors from teaching content,teaching method,teaching demonstration to teaching effect,the traditional single offline lecture is transformed into diversified and interactive modern teaching.The practical reform enriches and optimizes the course content,perfects and improves the course assessment system,and improves the teaching quality.It achieves the student-centered and application-oriented teaching goal,and also provides reference for further cultivating high-quality applied talents. 展开更多
关键词 Modern instrumental analysis BIOTECHNOLOGY Online and offline Reform of teaching
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Surgical Management of Lumbar Spinal Canal Stenosis with Instrumentation at the Yaounde Central Hospital: Comparison of Unilateral versus Bilateral Pedicle Screw Fixation Combined with Transforaminal Lumbar Interbody Fusion
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作者 Orlane Toto Ndome Nassourou Oumarou Haman +4 位作者 Dimitri Fogue Jean Bruno Ndoumou Ronaldo Fonju Anu Indira Baboke Vincent De Paul Djientcheu 《Open Journal of Modern Neurosurgery》 2024年第3期179-189,共11页
Introduction: The choice of adopting unilateral pedicle screw fixation or using bilateral pedicle screw fixation in lumbar spinal stenosis remains controversial. In our context, very few studies have been performed co... Introduction: The choice of adopting unilateral pedicle screw fixation or using bilateral pedicle screw fixation in lumbar spinal stenosis remains controversial. In our context, very few studies have been performed comparing the clinical effectiveness of unilateral versus bilateral fixation in the surgical management of lumbar spinal canal stenosis. Objective: Evaluate the impact on quality of life and clinical efficacy of unilateral spondylodesis compared to bilateral spondylodesis in the surgical management of lumbar spinal canal stenosis at the Yaounde Central Hospital. Methods: This was a retrospective descriptive cross-sectional study for a period of 4 years, from June 2015 to June 2019. It involved all patients operated for lumbar canal stenosis and who underwent spondylodesis or spinal fusion at the neurosurgery department of the Yaounde Central Hospital. Results: A total of 68 participants were recruited during our study period. 32 (47%) of the study population were in the 50 - 60 age group, with a mean age of 56.98 years ranging from 41 to 75 years. Females, housewives and farmers were the most affected. In our study, 72% of patients had unilateral spondylodesis and 28% had bilateral fusion. Preoperatively, 71% of patients had insurmountable pain, refractory to medical treatment. At 3 months postoperatively, 73.7% of patients with bilateral setup had moderate pain compared to 69% of those with unilateral setup. At 6 months postoperatively, 79% of patients with bilateral fusion had mild pain compared to 82% of patients with unilateral setup. At 1 year postoperatively, all patients had mild pain. Preoperatively, 66.2% of patients were unable to walk and 19.1% of patients were bedridden according to the Oswestry score. At 3 months postoperatively, 10.2% of patients with unilateral setup were unable to walk compared to 10.5% of patients with bilateral fixation, while 67.3% of patients with unilateral fixation had moderate disability compared to 52.6% of patients with bilateral fixation. At 6 months postoperatively, 51% of patients with unilateral setup had moderate disability compared to 47.4% of patients with bilateral fixation, while 42.9% of patients with unilateral fixation had mild disability compared to 42.1% of patients with bilateral fixation. At 1 year postoperatively, 81.6% of patients who underwent unilateral fixation had only mild disability compared to 73.7% of patients with bilateral fixation. Conclusion: The assessment of quality of life according to the set-up used shows similar results at 3 months, 6 months and 1 year, with no statistically significant differences. Single-sided pedicle screw fixation combined with transforaminal lumbar interbody fusion or mounting has the advantage of being faster, with less bleeding and is less expensive compared to bilateral fixation. 展开更多
关键词 Lumbar Spinal Canal STENOSIS instrumentATION Surgery Quality of Life
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Development and validation of an instrument to assess knowledge,attitudes,and practices on digital health among nursing officers
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作者 Maheshika Madhuwanthi Sunethra Jayathilake +1 位作者 Neranga Liyanaarachchige Rohana Marasinghe 《Frontiers of Nursing》 2024年第3期275-284,共10页
Objective:Validation is an important aspect of an instrument,and it ensures the confidence of researchers to employ the instrument in their studies.This study was conducted to develop and validate an instrument to ass... Objective:Validation is an important aspect of an instrument,and it ensures the confidence of researchers to employ the instrument in their studies.This study was conducted to develop and validate an instrument to assess knowledge,attitudes,and practices(KAP) on digital health among nurses since digital health capacity is a major concern in health care that needs to be assessed.Methods:We conducted a methodological study to assess the content validity and reliability of the instrument.First,items were generated through a comprehensive literature review and by obtaining an expert opinion.Second,content and face validity were assessed by a panel of 7 experts.Both the item-level content validity index(I-CVI) and the scale-level content validity index(S-CVI) were established.Moreover,test–retest reliability and internal consistency of the instrument were assessed.Data were analyzed using SPSS version 25.Results:The initial pool consisted of 60 items and after obtaining content,face,and construct validity,51 items remained.Items with an I-CVI <0.78 were considered relevant.The S-CVI for relevancy,clarity,ambiguity,and simplicity were 0.93,0.91,0.94,and 0.92,respectively.Five subcomponents were constructed in each knowledge and attitudes domain,and the test–retest reliability test revealed that the instrument has good reliability,showing correlation coefficient values for the KAP domains and the total questionnaire of 0.76,0.98,0.99,and 0.99,respectively.The independent Cronbach's α for all items was 0.76,indicating good internal consistency.Conclusions:The present study established the acceptable validity and ensured the good reliability and internal consistency of the instrument,which can serve as an assessment tool of KAP on digital health among healthcare professionals. 展开更多
关键词 assess DEVELOPMENT DIGITAL HEALTH instrument validations
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Analysis Of Urban Planning Instruments in Comala,Colima,Mexico(1997-2009)from a Gender Perspective-A Secondary Publication
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作者 E.J.García Espíritu P.Chung Alonso +2 位作者 I.BarajasÁvalos M.S.R.Covarrubias Ruesga M.P.Ramírez Rivera 《Journal of Architectural Research and Development》 2024年第1期93-101,共9页
This work is carried out based on the analysis of urban planning instruments,taking the gender perspective as a foundation.It arises from the inclusion of women in the participation of urban development,through an ana... This work is carried out based on the analysis of urban planning instruments,taking the gender perspective as a foundation.It arises from the inclusion of women in the participation of urban development,through an analysis of the gender gaps that have marked the history of women,the inequalities serve as a basis for carrying out this study.It highlights the challenges we face today as a society in the process of building citizen participation,where we must all be recognized and have equal opportunities within the territory in which we live.This article analyzes the extent to which the Municipal Urban Development Programs of the Mexican municipality of Comala,Colima,Mexico,consider the recommendations on gender and urbanism,established since the 1990s by international entities and applied transversally to urban planning policies.Considerable differences are found between women and men in terms of empowerment and participation in urban territorial planning instruments,mainly in the oldest instrument(1997).Significant progress is observed in the most recent document and is currently in force in the municipality of Comala(2009). 展开更多
关键词 Planning instruments Gender perspective Urban planning
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Instrument Automation Control System Faults and Maintenance
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作者 Jianwei Li 《Journal of Electronic Research and Application》 2024年第1期16-21,共6页
This article explores the topic of fault diagnosis and maintenance strategies for instrument automation control systems,analyzing them through specific cases.The aim of this research is to improve the stability and re... This article explores the topic of fault diagnosis and maintenance strategies for instrument automation control systems,analyzing them through specific cases.The aim of this research is to improve the stability and reliability of the system by conducting a thorough investigation of faults and maintenance in instrument automation control systems.By doing so,this research hopes to provide a strong guarantee for the smooth progress of industrial production. 展开更多
关键词 instrument automation Control system failure Maintenance
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Design of Signal Lamp Filament Monitoring Alarm Instrument
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作者 Haifeng Zhu 《Journal of Electronic Research and Application》 2024年第5期38-45,共8页
To improve the reliability of the light emitting diode(LED)signal lamp filament current monitoring alarm instrument for metro systems,a new type of hot standby online monitoring apparatus was developed which is based ... To improve the reliability of the light emitting diode(LED)signal lamp filament current monitoring alarm instrument for metro systems,a new type of hot standby online monitoring apparatus was developed which is based on synchronous transmission data(STD)bus technology.In this system,a double hot standby mode can be achieved by adopting bus arbitration.In addition,to detect the effective value of alternating current which is from 0 to 200 mA in the signal lamp lighting circuit,a precision rectifier signal conditioning circuit and an isolated acquisition circuit were designed.This new type of alarm instrument has high detection accuracy and could meet the functional requirements for metro signal systems after comparing it with some industry products that were applied on the spot. 展开更多
关键词 Signal lamp Monitoring alarm instrument Precision rectifier signal conditioning circuit
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端粒长度与10种常见肌肉骨骼疾病的关系孟德尔随机化分析
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作者 罗伟东 蒲彬 +3 位作者 古鹏 黄枫 郑晓辉 陈福洪 《中国组织工程研究》 CAS 北大核心 2025年第3期654-660,共7页
背景:多项观察性研究表明,端粒长度与肌肉骨骼疾病之间存在潜在的关联,然而它们之间的潜在机制仍不清楚。目的:利用两样本孟德尔随机化分析来探索端粒长度与肌肉骨骼疾病之间的遗传因果关系。方法:从英国生物银行中获得端粒长度的全基... 背景:多项观察性研究表明,端粒长度与肌肉骨骼疾病之间存在潜在的关联,然而它们之间的潜在机制仍不清楚。目的:利用两样本孟德尔随机化分析来探索端粒长度与肌肉骨骼疾病之间的遗传因果关系。方法:从英国生物银行中获得端粒长度的全基因组关联研究汇总数据。从FinnGen财团中获得了关于10种常见肌肉骨骼疾病(骨坏死、骨髓炎、骨质疏松、类风湿关节炎、腰痛、椎管狭窄、痛风、肩周炎、强直性脊柱炎和下肢深静脉血栓)的全基因组关联研究汇总数据。使用逆方差加权、孟德尔随机化-Egger和加权中位数方法评估端粒长度与10种肌肉骨骼疾病的因果关系,逆方差加权作为主要的孟德尔随机化分析方法,并进行敏感性分析探讨结果稳健性。结果与结论:①逆方差加权法结果表明,遗传预测的端粒长度与类风湿关节炎(OR=0.78,95%CI:0.64-0.95,P=0.015)和骨坏死(OR=0.56,95%CI:0.36-0.90,P=0.016)风险之间存在负向因果关系,但未发现端粒长度与其他8种肌肉骨骼疾病之间存在因果关系(P均>0.05)。②敏感性分析结果表明因果关系稳健,孟德尔随机化-Egger截距分析未检测到潜在的水平多效性(P均>0.05)。③此项孟德尔随机化研究支持端粒长度对类风湿关节炎和骨坏死的保护作用的结论,然而,未来将需要更多的基础和临床研究来验证。 展开更多
关键词 端粒长度 肌肉骨骼疾病 孟德尔随机化 全基因组关联研究 单核苷酸多态性 因果关系 工具变量
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虚拟仪器平台下旋转机械振动应用研究
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作者 曹慧 张锐英 +1 位作者 潘琦 方遒 《太原学院学报(自然科学版)》 2025年第1期63-70,共8页
利用LabVIEW软件图形化程序和可视化前面板,基于旋转机械结构和运动特点构建虚拟仪器仿真平台基本框架,设计了与真实仪器功能相当的旋转机械齿轮振动虚拟仿真研究平台。通过仿真验证,齿轮振动虚拟仿真平台能够有效采集振动信号,并对振... 利用LabVIEW软件图形化程序和可视化前面板,基于旋转机械结构和运动特点构建虚拟仪器仿真平台基本框架,设计了与真实仪器功能相当的旋转机械齿轮振动虚拟仿真研究平台。通过仿真验证,齿轮振动虚拟仿真平台能够有效采集振动信号,并对振动信号特征进行提取和分析,测试结果与旋转机械齿轮实际振动情况一致。开发的虚拟仿真平台达到了预期功能目标,为旋转机械关键部件振动检测和故障诊断提供了可视化技术支持,降低了旋转机械故障检测成本。 展开更多
关键词 齿轮振动 虚拟仪器 图形化程序 前面板 频谱分析
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基于特征间几何约束的指针仪表读数识别方法
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作者 刘昶 卢景峰 刘青 《沈阳理工大学学报》 CAS 2025年第1期1-8,共8页
在指针式仪表示值监控系统中,倾斜拍摄仪表图像时会导致识别结果出现偏差,为此提出一种基于仪表特征间几何约束的识别方法。首先利用一幅平铺于仪表上表面的平面标定板图像实现相机参数标定,生成仪表在标定平面上的虚拟图像;然后利用表... 在指针式仪表示值监控系统中,倾斜拍摄仪表图像时会导致识别结果出现偏差,为此提出一种基于仪表特征间几何约束的识别方法。首先利用一幅平铺于仪表上表面的平面标定板图像实现相机参数标定,生成仪表在标定平面上的虚拟图像;然后利用表壳上表面、刻度平面、指针平面与虚拟像平面间的平行关系,确定表壳圆的圆心、仪表刻度圆心、指针转轴中心特征间的透视投影约束关系,利用图像的极坐标变换和离散傅里叶变换提取仪表刻度圆心的最优位置及起始刻度线的角度,利用Hough变换的投票原理估计指针的转动角度;最后利用角度法实现仪表读数的解算。以某型号指针式温度计为测试对象进行实验验证,识别结果的平均误差为0.23℃,最大误差为0.7℃,本文方法能够准确识别仪表读数且识别精度优于人工读数。 展开更多
关键词 指针式仪表 透视投影约束 相机标定 离散傅里叶变换
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Research on the Testing Methods of Instrumental System in the Marine Magnetic Survey 被引量:1
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作者 边刚 刘雁春 +2 位作者 于波 肖付民 卞光浪 《Marine Science Bulletin》 CAS 2007年第2期1-11,共11页
Testing methods of instrumental system in the marine magnetic survey have been studied in this paper, and the feasibility of each method has been testified by the observed data. The conclusion shows that the method br... Testing methods of instrumental system in the marine magnetic survey have been studied in this paper, and the feasibility of each method has been testified by the observed data. The conclusion shows that the method brought out can effectively eliminate the systematic error caused by the instrumental system, and greatly improve the surveying precision and the reliability of the survey results. 展开更多
关键词 Marine magnetic survey instrumental system testing method
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