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Basic Characteristics of an Appropriate Waste Fillers for Solvent Free and Water-Borne Industrial Polymer Floors and Their Utilization
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作者 Jana Kosikova 《Journal of Civil Engineering and Architecture》 2024年第3期141-147,共7页
Recently the manufacture of epoxy coating and flooring materials begun to be under strong pressure to use more environmentally friendly raw materials in its composition.First tendency to reduce of solvents and diluent... Recently the manufacture of epoxy coating and flooring materials begun to be under strong pressure to use more environmentally friendly raw materials in its composition.First tendency to reduce of solvents and diluents contained in the materials appeared at the end of 90´s.This situation was supported by the Council of Europe in 2004 to reduce VOC emissions to zero till 2020.Solvent materials were thus largely replaced by solvent free materials from which the volatile substances are not released into the air.But pressure continued to increase,and over the past decade began to take centre stage water-based epoxy.On the Czech market solvent based material is still occasionally used,but predominant are solvent free materials.There are no commonly used materials containing wastes as fillers in new water-borne and solvent-free epoxy materials.Characteristics identification of the waste material as a potential filler is a set of properties that determine the limits of secondary raw materials or waste as a filler.This paper describes the basic characteristics which must be selected to meet the requirements,to affect negatively the workability,sedimentation,properties and behavior of the final floor system.Some materials must comply with special requirements,such as resistance to chemicals,etc.Next part of paper talks about utilization of polymer floors and their mechanical properties. 展开更多
关键词 Industrial polymer flooring materials waster fillers building materials
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从中国首台紫外-可见光高光谱卫星仪器反演得到的高空间分辨率臭氧廓线 被引量:1
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作者 Fei Zhao Cheng Liu +3 位作者 Qihou Hu Congzi Xia Chengxin Zhang Wenjing Su 《Engineering》 SCIE EI CAS CSCD 2024年第1期106-115,共10页
Understanding the vertical distribution of ozone is crucial when assessing both its horizontal and vertical transport,as well as when analyzing the physical and chemical properties of the atmosphere.One of the most ef... Understanding the vertical distribution of ozone is crucial when assessing both its horizontal and vertical transport,as well as when analyzing the physical and chemical properties of the atmosphere.One of the most effective ways to obtain high spatial resolution ozone profiles is through satellite observations.The Environmental Trace Gases Monitoring Instrument(EMI)deployed on the Gaofen-5 satellite is the first Chinese ultraviolet-visible hyperspectral spectrometer.However,retrieving ozone profiles using backscattered radiance values measured by the EMI is challenging due to unavailable measurement errors and a low signal-to-noise ratio.The algorithm developed for the Tropospheric Monitoring Instrument did not allow us to retrieve 87%of the EMI pixels.Therefore,we developed an algorithm specific to the characteristics of the EMI.The fitting residuals are smaller than 0.3%in most regions.The retrieved ozone profiles were in good agreement with ozonesonde data,with maximum mean biases of 20%at five latitude bands.By applying EMI averaging kernels to the ozonesonde profiles,the integrated stratospheric column ozone and tropospheric column ozone also showed excellent agreement with ozonesonde data,The lower layers(0-7.5 km)of the EMI ozone profiles reflected the seasonal variation in surface ozone derived from the China National Environmental Monitoring Center(CNEMC).However,the upper layers(9.7-16.7 km)of the ozone profiles show different trends,with the ozone peak occurring at an altitude of 9.7-16.7 km in March,2019.A stratospheric intrusion event in central China from August 11 to 15,2019,is captured using the EMI ozone profiles,potential vorticity data,and relative humidity data.The increase in the CNEMC ozone co ncentration showed that downward transport enhanced surface ozone pollution. 展开更多
关键词 Ozone profiles EMI Soft calibration Floor noise correction Stratospheric ozone intrusion
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Restraint effect of partition wall on the tunnel floor heave in layered rock mass
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作者 YANG Yunyun HUANG Da +2 位作者 ZHONG Zhu LIU Yang PENG Jianbing 《Journal of Mountain Science》 SCIE CSCD 2024年第7期2462-2479,共18页
The presence of horizontal layered rocks in tunnel engineering significantly impacts the stability and strength of the surrounding rock mass,leading to floor heave in the tunnel.This study focused on preparing layered... The presence of horizontal layered rocks in tunnel engineering significantly impacts the stability and strength of the surrounding rock mass,leading to floor heave in the tunnel.This study focused on preparing layered specimens of rock-like material with varying thickness to investigate the failure behaviors of tunnel floors.The results indicate that thin-layered rock mass exhibits weak interlayer bonding,causing rock layers near the surface to buckle and break upwards when subjected to horizontal squeezing.With an increase in the layer thickness,a transition in failure mode occurs from upward buckling to shear failure along the plane,leading to a noticeable reduction in floor heave deformation.The primary cause of significant deformation in floor heave is upward buckling failure.To address this issue,the study proposes the installation of a partition wall in the middle of the floor to mitigate heave deformation of the rock layers.The results demonstrate that the partition wall has a considerable stabilizing effect on the floor,reducing the zone of buckling failure and minimizing floor heave deformation.It is crucial for the partition wall to be sufficiently high to prevent buckling failure and ensure stability.Through simulation calculations on an engineering example,it is confirmed that implementing a partition wall can effectively reduce floor heave and enhance the stability of tunnel floor. 展开更多
关键词 Layered rock Floor heave Horizontal compression test Failure behavior Partition wall
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Study on Evacuation Strategy of Commercial High-Rise Building under Fire Based on FDS and Pathfinder
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作者 Zheng Yan Ying Wang +1 位作者 Longxiao Chao Jian Guo 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期1077-1102,共26页
With the development of economy and society and the growth of population,the high-rise and multi-function of commercial buildings have become an international trend.But it also poses huge fire hazards.Most of the exis... With the development of economy and society and the growth of population,the high-rise and multi-function of commercial buildings have become an international trend.But it also poses huge fire hazards.Most of the existing studies’research objects are predominantly high-rise residential buildings,without considering the impact of different functional zones(Standard floor,entertainment zone,office zone,equipment room and so on)and personnel distribution of commercial buildings evacuation.And the influence of using elevators to carry evacuees on the refuge floor on personnel evacuation is rarely studied.In this work,the fire scenario of the Yangtze River InternationalConferenceCenter,a high-rise commercial building,is simulated with the Pyrosim programto get the necessary parameters under various fire scenarios and to calculate the available evacuation time TASET.At the same time,according to the complex functional zone of the commercial high-rise building and the distribution of people in different time periods,a reasonable evacuation strategy is developed and simulated by Pathfinder software.The results indicate that unorganized evacuation will lead individuals to take the erroneous evacuation route,resulting in a vast region of congestion;comprehensive consideration of the time staggering and the reasonable distribution of evacuation routes can significantly improve evacuation efficiency,and the TRSET of night and working hours is 36.6%–55.3%and 49.9%–79.6%of unorganized evacuation,respectively.For the night fire,60%of the people use elevator-refuge floor to evacuate is the optimal strategy;for the fire during working hours,half of the people on standard floors use the elevator to evacuate and people on multifunctional floors evacuate in four batches is the best plan.The results of this study can provide viable solutions and a foundation for analyzing the fire evacuation and safety of big commercial high-rise buildings. 展开更多
关键词 High-rise building fire personnel evacuation refuge floor safety analysis
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Curative effect of hydrogen peroxide combined with silver ion disinfection on pelvic floor dysfunction
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作者 Wei Zhou Hua Guo 《World Journal of Clinical Cases》 SCIE 2024年第21期4508-4517,共10页
BACKGROUND Pelvic floor dysfunction(PFD)is related to muscle fiber tearing during childbirth,negatively impacting postpartum quality of life of parturient.Appropriate and effective intervention is necessary to promote... BACKGROUND Pelvic floor dysfunction(PFD)is related to muscle fiber tearing during childbirth,negatively impacting postpartum quality of life of parturient.Appropriate and effective intervention is necessary to promote PFD recovery.AIM To analyze the use of hydrogen peroxide and silver ion disinfection for vaginal electrodes in conjunction with comprehensive rehabilitation therapy for postpartum women with PFD.METHODS A total of 59 women with PFD who were admitted to the hospital from May 2019 to July 2022 were divided into two groups:Control group(n=27)received comprehensive rehabilitation therapy and observation group(n=32)received intervention with pelvic floor biostimulation feedback instrument in addition to comprehensive rehabilitation therapy.The vaginal electrodes were disinfected with hydrogen peroxide and silver ion before treatment.Intervention for both groups was started 6 weeks postpartum,and rehabilitation lasted for 3 months.Pelvic floor muscle voltage,pelvic floor muscle strength,vaginal muscle voltage,vaginal muscle tone,pelvic floor function,quality of life,and incidence of postpartum PFD were compared between the two groups.RESULTS Before comprehensive rehabilitation treatment,basic data and pelvic floor function were not significantly different between the two groups.After treatment,the observation group showed significant improvements in the maximum voltage and average voltage of pelvic floor muscles,contraction time of type I and type II fibers,pelvic floor muscle strength,vaginal muscle tone,vaginal muscle voltage,and quality of life(GQOLI-74 reports),compared with the control group.The observation group had lower scores on the pelvic floor distress inventory(PFDI-20)and a lower incidence of postpartum PFD,indicating the effectiveness of the pelvic floor biostimulation feedback instrument in promoting the recovery of maternal pelvic floor function.CONCLUSION The combination of the pelvic floor biostimulation feedback instrument and comprehensive rehabilitation nursing can improve pelvic floor muscle strength,promote the recovery of vaginal muscle tone,and improve pelvic floor function and quality of life.The use of hydrogen peroxide and silver ion disinfectant demonstrated favorable antibacterial efficacy and is worthy of clinical application. 展开更多
关键词 Pelvic floor biostimulation feedback instrument Comprehensive rehabilitation therapy Postpartum pelvic floor dysfunction Vaginal electrode Disinfection with hydrogen peroxide and silver ion Nanocolloidal silver
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Botulinum toxin type A injection combined with biofeedback in the treatment of spastic pelvic floor syndrome
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作者 Fei-Fei Sun Yong-Qiang Chen +1 位作者 Zong-Lin Jiang Lin Ma 《World Journal of Clinical Cases》 SCIE 2024年第22期4905-4912,共8页
BACKGROUND Spastic pelvic floor syndrome(SPFS)is a refractory pelvic floor disease characterized by abnormal(uncoordinated)contractions of the external anal sphincter and puborectalis muscle during defecation,resultin... BACKGROUND Spastic pelvic floor syndrome(SPFS)is a refractory pelvic floor disease characterized by abnormal(uncoordinated)contractions of the external anal sphincter and puborectalis muscle during defecation,resulting in rectal emptation and obstructive constipation.The clinical manifestations of SPFS are mainly characterized by difficult defecation,often accompanied by a sense of anal blockage and drooping.Manual defecation is usually needed during defecation.From physical examination,it is commonly observed that the patient's anal muscle tension is high,and it is difficult or even impossible to enter with his fingers.AIM To investigate the characteristics of anorectal pressure and botulinum toxin A injection combined with biofeedback in treating pelvic floor muscle spasm syndrome.METHODS Retrospective analysis of 50 patients diagnosed with pelvic floor spasm syndrome.All patients underwent pelvic floor surface electromyography assessment,anorectal dynamics examination,botulinum toxin type A injection 100 U intramuscular injection,and two cycles of biofeedback therapy.RESULTS After the botulinum toxin A injection combined with two cycles of biofeedback therapy,the patient's postoperative resting and systolic blood pressure were significantly lower than before surgery(P<0.05).Moreover,the electromyography index of the patients in the resting stage and post-resting stages was significantly lower than before surgery(P<0.05).CONCLUSION Botulinum toxin A injection combined with biofeedback can significantly reduce pelvic floor muscle tension in treating pelvic floor muscle spasm syndrome.Anorectal manometry is an effective method to evaluate the efficacy of treatment objectively.However,randomized controlled trials are needed. 展开更多
关键词 Spastic pelvic floor syndrome Botulinum toxin A BIOFEEDBACK Anorectal pressure measurement Agachan constipation score
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Effect of continuous nursing on treatment compliance and side effect management of coronary heart disease
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作者 Juan Wei Bai-Wen-Xian Li +2 位作者 Shao-Jie Han Hong-Jie Zhuang Wen-Hong Cao 《World Journal of Clinical Cases》 SCIE 2024年第19期3701-3707,共7页
BACKGROUND There are relatively few studies on continuing care of coronary heart disease(CHD),and its research value needs to be further clarified.AIM To investigate the effect of continuous nursing on treatment compl... BACKGROUND There are relatively few studies on continuing care of coronary heart disease(CHD),and its research value needs to be further clarified.AIM To investigate the effect of continuous nursing on treatment compliance and side effect management in patients with CHD.METHODS This is a retrospective study with patients from January 2021 to 2023.The study was divided into two groups with 30 participants in each group.Self-rating anxiety scale(SAS)and Self-rating depression scale(SDS)were used to assess patients'anxiety and depression,and medical coping questionnaire was used to assess patients'coping styles.The pelvic floor dysfunction questionnaire(PFDI-20)was used to assess the status of pelvic floor function,including bladder symptoms,intestinal symptoms,and pelvic symptoms.RESULTS SAS score decreased from 57.33±3.01before treatment to 41.33±3.42 after treatment,SDS score decreased from 50.40±1.45 to 39.47±1.57.The decrease of these two indexes was statistically significant(P<0.05).PFDI-20 scores decreased from the mean 16.83±1.72 before treatment to 10.47±1.3the mean after treatment,which was statistically significant(P<0.05).CONCLUSION The results of this study indicate that pioneering research in continuous care of CHD has a positive impact on improving patients'treatment compliance,reducing anxiety and depression levels,and improving coping styles and pelvic floor functional status. 展开更多
关键词 Coronary heart disease Continuing care Treatment compliance Anxiety and depression Coping style Pelvic floor function status Pioneering study
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Tea for Harmony Yaji Cultural Salon Inviting the Nigerians to Enjoy the Tea Culture
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作者 Qin Fangfang 《China & The World Cultural Exchange》 2024年第7期10-10,共1页
On June 20,Tea for Harmony Yaji Cultural Salon held by China Cultural Centerattracted dozens of students of the Chinese class of the cultural center and their relatives and friends.All of them sat together,sharing tea... On June 20,Tea for Harmony Yaji Cultural Salon held by China Cultural Centerattracted dozens of students of the Chinese class of the cultural center and their relatives and friends.All of them sat together,sharing tea fragrance and tea culture.The event was held in the form of salon,using the way of sitting on the floor to create a relaxed and warm atmosphere,allowing guests to immerse themselves in the Chinese tea culture. 展开更多
关键词 HARMONY floor relaxed
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Various Aetiologies of Non-Traumatic Coccydynia Cause Pain in the Posterior Sacrococcygeal Leg of the Pelvic Tripod: A Burden on the Healthcare Sector
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作者 Kumar Satya Nandivada Venkata Kiran Nadavinamani Shivanand Raghavendra +3 位作者 Oommen Elsy Biju Bharadwaja Nikhil Nandivada Nandivada Vaishnavi Rizvi Usama Ahmed 《Open Journal of Orthopedics》 2024年第7期334-353,共20页
Introduction: Coccydynia, television disease, and coccygodynia are the different names given to this disabling disease, which can become chronic. It was described by Simson in 1859. Coccydynia means pain at the end of... Introduction: Coccydynia, television disease, and coccygodynia are the different names given to this disabling disease, which can become chronic. It was described by Simson in 1859. Coccydynia means pain at the end of the vertebral column. Non-traumatic coccydynia is a diagnosis, which is never straightforward like traumatic coccydynia because the onset is unclear, and both the patient and the unaware clinician face many challenges in treating it on time and with accuracy. Coccyx was likened to a cuckoo bird’s beak as a curved bone of fused 3 to 5 vertebrae with remnant disc material in some rare cases, unfused segments, linear scoliosis or subluxations and deformities. Stress X-rays of the coccyx in the antero-posterior and lateral views in standing and sitting reveal the “Dynamic Instability” due to congenital coccygeal morphological, pathological and mechanical variations. Material and Methods: This is a complex study having retrograde data collected from online publications from various databases, like PubMed, Embase, and Cochrane Library and also antegrade data collected from 100 patients with their consent from patients in Adam and Eve Specialised Medical Centre-based at Abu Dhabi, UAE and data was processed in the research centre of Krushi Orthopaedic Welfare Society based in India between 2014-2024 following all guidelines of Helsinki and approved by the ethics board of Krushi Orthopaedic Welfare Society. Clinical Presentation: The coccyx is painful, with aches, spasms, and an inability to sit. This affects daily activities without any particular date of onset. The onset remains insidious for the non-traumatic variety of coccydynia. Aetiology and Patho Anatomy: Non-traumatic coccydynia can be caused by a myriad of reasons, like congenital morphological variations, acquired dynamic instabilities, and hidden trauma remaining quiescent to re-surface as a strain-induced pain. Radiological Presentations: Unless clarity is focused on these coccygeal views, the errors of the unevacuated rectum, non-dynamic standing views, improper X-ray exposure and refuge by insurance companies to approve the much needed but multiple views in radiological investigation (Stress X-ray), MRI scan, lack of awareness by the clinician, all lead to missed diagnosis with its repercussions as congenital variations in morphology, acquired changes in structure/mobility, pathologies like tumours like congenital teratoma & adult onset chordoma, Tarlov cysts, pilonidal sinus or infections—even tuberculosis, dural syndrome, stiff coccyx due to ankylosing spondylitis and many others like relation to neurosis have all been documented. Treatment options are outside the scope of this research topic, as only the differential diagnosis is being stressed here, so that the clinician and the patient do not overlook the varying aetiology, which is the first step to timely and appropriate treatment. Conclusion: Level 3 evidence is available pointing towards many aetiologies causing non-traumatic coccydynia, and in this study of 100 patients by Krushi O W S, a non-profit organisation, the results were as follows: 1) Coccydynia is more common in Type II coccyx and bony spicules. 2) Coccydynia is more prevalent when the sacrococcygeal joints are not fused. 3) Coccydynia is more prevalent when there is subluxation at the intercoccygeal joints. 4) Coccydynia is more when the sacral angle is lower. 5) Coccydynia is associated with higher sacrococcygeal curved length. 6) Coccydynia is associated with a lower sacrococcygeal curvature index. 7) Gender variations: The coccygeal curvature index was lower in females with coccydynia;the intercoccygeal angle was lower in males. 8) Both obese and thin individuals can get affected due to different weight-bearing mechanics in play. 展开更多
关键词 COCCYDYNIA Coccygodynia Pelvic Floor CHORDOMA Pilonidal Sinus Fused Sacrococcygeal Segment Non-Traumatic Coccydynia Entrapment of Coccygeal Nerves Dural Syndrome
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Further Analysis of Machine Tool Dimensional Accuracy and Thermal Stability under Varying Floor Temperature
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作者 Joel Arumun Shadrack Abiola 《World Journal of Engineering and Technology》 2024年第2期258-273,共16页
Machining is as old as humanity, and changes in temperature in both the machine’s internal and external environments can be of great concern as they affect the machine’s thermal stability and, thus, the machine’s d... Machining is as old as humanity, and changes in temperature in both the machine’s internal and external environments can be of great concern as they affect the machine’s thermal stability and, thus, the machine’s dimensional accuracy. This paper is a continuation of our earlier work, which aimed to analyze the effect of the internal temperature of a machine tool as the machine is put into operation and vary the external temperature, the machine floor temperature. Some experiments are carried out under controlled conditions to study how machine tool components get heated up and how this heating up affects the machine’s accuracy due to thermally induced deviations. Additionally, another angle is added by varying the machine floor temperature. The parameters mentioned above are explored in line with the overall thermal stability of the machine tool and its dimensional accuracy. A Robodrill CNC machine tool is used. The CNC was first soaked with thermal energy by gradually raising the machine floor temperature to a certain level before putting the machine in operation. The machine was monitored, and analytical methods were deplored to evaluate thermal stability. Secondly, the machine was run idle for some time under raised floor temperature before it was put into operation. Data was also collected and analyzed. It is observed that machine thermal stability can be achieved in several ways depending on how the above parameters are joggled. This paper, in conclusion, reinforces the idea of machine tool warm-up process in conjunction with a carefully analyzed and established machine floor temperature variation for the approximation of the machine tool’s thermally stability to map the long-time behavior of the machine tool. 展开更多
关键词 Dimensional Accuracy Machine Tool Machine Floor Thermal Stability TEMPERATURE Thermal Deviation
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Smooth Operators
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作者 XIA YUANYUAN 《ChinAfrica》 2024年第7期20-22,共3页
Automation,digitisation,and innovation lead the way in Shanghai’s industrial upgrading Automated guided vehicles shuttle through the workshop and transport various parts to different production lines.The huge robotic... Automation,digitisation,and innovation lead the way in Shanghai’s industrial upgrading Automated guided vehicles shuttle through the workshop and transport various parts to different production lines.The huge robotic arm completes each step incessantly and quietly.The humming sound of machines and noise of factory floor conversations associated with traditional manufacturing processes are largely absent. 展开更多
关键词 FLOOR DIGIT WORKSHOP
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Concentrations and seasonal dynamics of dissolved organic carbon in forest floors of two plantations (Castanopsis kawakamii and Cunninghamia lanceolata) in subtropical China 被引量:7
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作者 ZHANG Jiang-shan GUO Jian-fen +1 位作者 CHEN Guang-shui QIAN Wei 《Journal of Forestry Research》 SCIE CAS CSCD 2005年第3期205-208,共4页
The concentrations and seasonal dynamics of DOC in forest floors of monoculture plantations of Castanopsis kawakamii and Chinese fir (Cunninghamia lanceolata) were assessed in Sanming, Fujian, China (26°11′30... The concentrations and seasonal dynamics of DOC in forest floors of monoculture plantations of Castanopsis kawakamii and Chinese fir (Cunninghamia lanceolata) were assessed in Sanming, Fujian, China (26°11′30″N, 117°26′00″E). Forest floor samples were taken in January, April, July and October in 2002 and divided into undecomposed material (horizon Oi), partially decomposed organic material (horizon Oe), and fully decomposed organic material (horizon Oa). Upon collection. DOC concentrations of samples were analyzed by a High Temperature TOC. The results showed that the annual average DOC concentration of Chinese fir (1341.7 mg·kg^-1) in the forest floor was higher than that of Castanopsis kawakamii ( 1178.9 mg·kg^-1). Difference in DOC concentrations was observed among three horizons of the forest floor. DOC concentration of forest floor in the two forests was the highest in horizon Oe. Seasonal trends of DOC concentrations in different horizons of forest floors were similar and the maximal value occurred in autumn (or winter). The concentration and temporal change of DOC in studied forests were probably related to the variation in moisture, temperature, biological activity and quantity of organic matter in the forest floor. 展开更多
关键词 Dissolved organic carbon (DOC) Seasonal dynamics Forest floor Castanopsis kawakamii Cunninghamia lanceolata matter in the forest floor.
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Comprehensive evaluation of water-inrush risk from coal floors 被引量:9
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作者 WEI Jiuchuan LI Zhongjian +2 位作者 SHI Longqing GUAN Yuanzhang YIN Huiyong 《Mining Science and Technology》 EI CAS 2010年第1期121-125,共5页
Lower groups of coal seams are presently being mined from water-inrush from coal floors in order to have safe production in the Yanzhou coal mining area. We need to evaluate the risk in the lower groups of coal seams ... Lower groups of coal seams are presently being mined from water-inrush from coal floors in order to have safe production in the Yanzhou coal mining area. We need to evaluate the risk in the lower groups of coal seams in mines. Based on a systematic collection of hydrogeological data and some data from mined working faces in these lower groups, we evaluated the factors affecting water-inrush from coal floors of the area by a method of dimensionless analysis. We obtained the order of the factors affecting water-inrush from coal floors and recalculated data on depths of destroyed floors by multiple linear regression analysis and obtained new empirical formulas. We also analyzed the water-inrush coefficient of mined working faces of the lower groups of coal seams and improved the evaluation standard of the water-inrush coefficient method. Finally, we made a comprehensive evaluation of water-inrush risks from coal floors by using the water-inrush coefficient method and a fuzzy clustering method. The evaluation results provide a solid foundation for preventing and controlling the damage caused by water of an Ordovician limestone aquifer in the lower group of coal seams in the mines of Yanzhou. It provides also important guidelines for lower groups of coal seams in other coal mines. 展开更多
关键词 water-inrush from floors fuzzy clustering factors affecting water-inrush from coal floors lower groups of coal seams dimensionless analysis
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Relationship between water inrush from coal seam floors and main roof weighting 被引量:4
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作者 Sun Jian Hu Yang Zhao Guangming 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2017年第5期873-881,共9页
A water-resistant key strata model of a goaf floor prior to main roof weighting was developed to explore the relationship between water inrush from the floor and main roof weighting. The stress distribution,broken cha... A water-resistant key strata model of a goaf floor prior to main roof weighting was developed to explore the relationship between water inrush from the floor and main roof weighting. The stress distribution,broken characteristics, and the risk area for water inrush of the water-resistant key strata were analysed using elastic thin plate theory. The formula of the maximum water pressure tolerated by the waterresistant key strata was deduced. The effects of the caved load of the goaf, the goaf size prior to main roof weighting, the advancing distance of the workface or weighting step, and the thickness of the waterresistant key strata on the breaking and instability of the water-resistant key strata were analysed.The results indicate that the water inrush from the floor can be predicted and prevented by controlling the initial or periodic weighting step with measures such as artificial forced caving, thus achieving safe mining conditions above confined aquifers. The findings provide an important theoretical basis for determining water inrush from the floor when mining above confined aquifers. 展开更多
关键词 FLOOR WATER inrush Main ROOF weighting Water-resistant key STRATA FORCED CAVING
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Combined ANN prediction model for failure depth of coal seam floors 被引量:5
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作者 WANG Lian-guo ZHANG Zhi-kang +4 位作者 LU Yin-long YANG Hong-bo YANG Sheng-qiang SUN Jian ZHANG Jin-yao 《Mining Science and Technology》 EI CAS 2009年第5期684-688,共5页
Failure depth of coal seam floors is one of the important considerations that must be kept in mind when mining is carried out above a confined aquifer. In order to study the factors that affect the failure depth of co... Failure depth of coal seam floors is one of the important considerations that must be kept in mind when mining is carried out above a confined aquifer. In order to study the factors that affect the failure depth of coal seam floors such as mining depth, coal seam pitch, mining thickness, workface length and faults, we propose a combined artificial neural networks (ANN) prediction model for failure depth of coal seam floors on the basis of existing engineering data by using genetic algorithms to train the ANN. A practical engineering application at the Taoyuan Coal Mine indicates that this method can effectively determine the network struc- ture and training parameters, with the predicted results agreeing with practical measurements. Therefore, this method can be applied to relevant engineering projects with satisfactory results. 展开更多
关键词 artificial neural networks (ANN) floor failure depth genetic algorithms PREDICTION
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Test and Analysis of the Sound Insulation Performance of Four Types of Timber Structure Floors under Jumping Excitation 被引量:1
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作者 Yujie Huang Hao Zhu +3 位作者 Dauletbek Assima Zheng Wang Minmin Li Xinyue Zhao 《Journal of Renewable Materials》 SCIE EI 2021年第4期829-840,共12页
To improve the impact sound insulation performance of building floors and meet the objective requirements for living comfort of residents,in this article,three kinds of elastic cushion materials,Portuguese cork board,... To improve the impact sound insulation performance of building floors and meet the objective requirements for living comfort of residents,in this article,three kinds of elastic cushion materials,Portuguese cork board,BGL insulation sound insulation foam board,and EPP polypropylene plastic foam board,are applied to the sound insulation of a light frame wood floor structure of the same bedroom and compared to the ordinary floor.This study uses the transfer function method and transient excitation method to measure the sound insulation,damping ratio,and elastic modulus of materials,as well as the sound insulation of the floor under the jumping excitation method of daily behavior.Through comparative analysis,the results and factors of improving the sound insulation performance of the floor are obtained,according to which three types of elastic cushion materials and the floor covering composed of them have higher vibration and noise reduction performance.Among them,the overall sound insulation performance of BGL board floor is the highest,followed by EPP board and cork board floor,and ordinary OSB floor is the lowest.Under the jumping excitation method,three floating floors can improve the impact sound insulation performance of the middle and low-frequency bands. 展开更多
关键词 Timber floor structure elastic cushion material damping ratio elastic modulus jumping excitation method of daily behavior testing and comparative analysis
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Technology of back stoping from level floors in gateway and pillar mining areas of extra-thick seams 被引量:2
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作者 Tu Hongsheng Tu Shihao +2 位作者 Zhang Xiaogang Li Zhaoxin Jia Shuai 《International Journal of Mining Science and Technology》 SCIE EI 2014年第2期143-149,共7页
According to the special requirements of secondary mining of resources in gateway-and-pillar goal in extra-thick seams of Shanxi, this paper presents a technical proposal of back stoping from level floors. Numerical s... According to the special requirements of secondary mining of resources in gateway-and-pillar goal in extra-thick seams of Shanxi, this paper presents a technical proposal of back stoping from level floors. Numerical simulation and theoretical analysis are ccsed to investigate the compaction characteristics of cavities under stress as well as an appropriate mining height of the primary-mining layer based on dif- ferent mining widths and pillar widths. For Yangjian coal mine, the mining thickness of the first seam during back stoping from level floor is determined to be 3 m, which meets the relevant requirements. Gateway-and-pillar goaf of a single layer has a range of influence of 9 m vertically. If gateway-and-pillar goaf occurs both in 9-1 and 9-5 layers, the range is extended to within 11.2 m. When the mining width of a gateway is less than 2 m or larger than 5 m, the gateway-and-pillar goal in the upper layer of the primary-mining seam can be filled in and compacted after stoping. When the working face is 2 m away from the gateway and pillar before entering into it and after passing through it, the coal body under the gateway and pillar is subjected to relatively high stress. During mining of the upper layer, moreover, the working face should interlock the goaf in primary-mining layer for 20 m. 展开更多
关键词 Gateway-and-pillar goaf Back stoping from level floor Secondary mining Numerical simulation Stress evolution
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Impact Noise of Non-homogeneous Floors: Analysis of Different Input Parameters for Computational Modeling Predictions 被引量:1
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作者 Maria Fernanda de Oliveira Jorge Vicoso Patricio2 《Journal of Civil Engineering and Architecture》 2017年第3期274-281,共8页
Floor systems with non-homogeneous slabs have more complex means of propagation than homogeneous systems, with more variables to be considered in predictions by theoretical models. For those slabs, it is necessary to ... Floor systems with non-homogeneous slabs have more complex means of propagation than homogeneous systems, with more variables to be considered in predictions by theoretical models. For those slabs, it is necessary to understand the differences of each material composing each subsystem, and the connection types between the elements of each one of this subsystem. Some floors integrating lightweight elements without structural purposes, are broadly used in several countries in precast slabs. The predictions based on computer modelling for building systems can be influenced by the input parameters related to connections between the elements of the floor system. In building structures, the analysis of radiation due to element vibrations may be represented by wave propagation relationships as a one-dimensional system, a two-dimensional system or a three-dimensional solid. In these floors, the modelling of the interaction between elements can be basically a face, a line or a point connection. In addition, the choice of the connection type can determine the vibration transmission amongst all the floor elements. This study focuses on the differences that can be obtained in the induced vibration response due to an impact source on non-homogeneous slabs. It also presents some examples of modelling options for several floor systems, considering input parameters for different connection types. 展开更多
关键词 Non-homogeneous floors vibrational response finite element analysis.
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Applications and Prospects of Fiber Reinforced Concrete in Industrial Floors 被引量:1
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作者 Hesham Alsharie 《Open Journal of Civil Engineering》 2015年第2期185-189,共5页
Upon the view of this work, industrial floor is a vital structure due to its relation to quality of production, labor comfort, and human health. Flooring costs may reach 20% of single-story building construction expen... Upon the view of this work, industrial floor is a vital structure due to its relation to quality of production, labor comfort, and human health. Flooring costs may reach 20% of single-story building construction expenditure, and the consumption of concrete for floors may come to 40% - 50% of the total size of concrete. Thereby, the efficient design of floor will reduce materials consumption and labor, and will increase the endurance of the floor. Fiber reinforcement reduces the thickness of the subfloor about 20% - 30%, hence enabling to reduce the consumption of cement and fillers. The use of fiber meshes will enable to save 30% - 40% of steel. Despite the flexible use of fiber in concrete reinforcement saves effort and money, still fiber reinforced concrete is lacking additional regulations in Jordan. 展开更多
关键词 FIBER REINFORCED CONCRETE Industrial floors JORDAN
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China floors“两种资源”瞄准“一个市场”的国际策略——采访China floors地板有限公司曾志文总裁
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作者 施金 《国际木业》 2005年第4期16-16,共1页
从欧洲和俄罗斯的原料,到中国大陆的规模生产,再到进入发达市场的销售网络,来自中国台湾的企业家曾志文领导 China floors 这条运作全球的地板价值链。无怪乎在他的话语中“评估”这个词汇如此高频出现,链条中无论哪一小段出现危机都将... 从欧洲和俄罗斯的原料,到中国大陆的规模生产,再到进入发达市场的销售网络,来自中国台湾的企业家曾志文领导 China floors 这条运作全球的地板价值链。无怪乎在他的话语中“评估”这个词汇如此高频出现,链条中无论哪一小段出现危机都将波及企业整体—— 展开更多
关键词 China floors地板有限公司 中国 台湾省 企业管理 市场竞争力 质量管理
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