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| 1 | Loading characteristics of mechanical rib bolts determined through testing and numerical modeling显示文摘Underground coal mines use mechanical bolts in addition to other types of bolts to control the rib deformation and to stabilize the yielded coal ribs.Limited research has been conducted to understand the performance of the mechanical bolts in coal ribs.Researchers from the National Institute for Occupational Safety and Health(NIOSH)conducted this work to understand the loading characteristics of mechanical bolts(stiffness and capacity)installed in coal ribs at five underground coal mines.Standard pull-out tests were performed in this study to define the loading characteristics of mechanical rib bolts.Different installation torques were applied to the tested bolts based on the strength of the coal seam.A typical tri-linear load-deformation response for mechanical bolts was obtained from these tests.It was found that the anchorage capacity depended mainly on the coal strength.Guidelines for modeling mechanical bolts have been developed using the tri-linear load-deformation response.The outcome of this research provides essential data for rib support design. | Khaled Mohamed Gamal Rashed Zorica Radakovic-Guzina | 2020 | International Journal of Mining Science and Technology2020，30，1： | 4 |
| 2 | Effect of aqueous extract of Solanum xanthocarpum Schrad. & Wendl. on postmenopausal syndrome in ovariectomized rats显示文摘OBJECTIVE: Solanum xanthocarpum Schrad. & Wendl.(Solanaceae) is present in many Ayurveda compound formulations including Chavanaprasha and Dasamoolarishta. The whole plant is used in conditions such as inflammation, constipation and promoting conception in females. In the present study, we carried out different tests to evaluate the effect of aqueous extract of Solanum xanthocarpum(SXE) in postmenopausal syndrome. METHODS: The study was carried out in bilaterally ovariectomized one-month-old Wistar rats(40–50 g). Bilaterally ovariectomized(OVX) Wistar rats were divided into four groups(n=6) receiving different treatments, consisting of a vehicle(distilled water), aqueous extract of Solanum xanthocarpum at two different doses(200 and 400 mg/kg) administered orally daily for 90 d and standard drug β estradiol at a dose of 1 mg/kg administered subcutaneously biweekly for 90 d. Estrogenic activity was assessed by vaginal cornifi cation, sexual behavior, serum estradiol and uterine weight to body weight ratio. Antiosteoporotic activity was assessed on the basis of biomechanical and biochemical parameters followed by histopathological studies, and antidepressant activity was assessed by forced swim test. RESULTS: SXE showed presence of steroids. At the dose of 200 mg/kg, it signifi cantly improved all the parameters of sexual behavior(P<0.01), caused vaginal cornifi cation, and increased serum estradiol and uterine weight(P<0.01). It also significantly improved all the parameters of bone strength as well as depression(P<0.01). Histopathology of bones confi rmed the above fi ndings. CONCLUSION: The study indicated that SXE may provide an effective treatment in the prevention of postmenopausal symptoms. | Urmila Aswar Mayuri Gurav Ganesh More Khaled Rashed Manoj Aswar | 2014 | Journal of Integrative Medicine2014，12，5： | 3 |
| 3 | Antioxidant and Antiproliferative Activity of Diospyros lotus L. Extract and Isolated Compounds显示文摘 | Monica Rosa Loizzo Ataa Said Rosa Tundis Usama W. Hawas Khaled Rashed Federica Menichini Natale Giuseppe Frega Francesco Menichini | 2009 | Plant Foods for Human Nutrition2009，，4： | 1 |
| 4 | Finding a Practical IT Solution-Open Source Accounting Software显示文摘 | Manar Abu Talib Adel Khelifi Osama El-Temtamy Fatima Ismaeel Mahra Rashed Najah Hasan Summaya Khaled | 2012 | 通讯和计算机(中英文版)2012，9，4： | 1 |
| 5 | A multi-purpose National Forest Inventory in Bangladesh:design,operationalisation and key results显示文摘Background:National forest inventory and forest monitoring systems are more important than ever considering continued global degradation of trees and forests.These systems are especially important in a country like Bangladesh,which is characterised by a large population density,climate change vulnerability and dependence on natural resources.With the aim of supporting the Government’s actions towards sustainable forest management through reliable information,the Bangladesh Forest Inventory(BFI)was designed and implemented through three components:biophysical inventory,socio-economic survey and remote sensing-based land cover mapping.This article documents the approach undertaken by the Forest Department under the Ministry of Environment,Forests and Climate Change to establish the BFI as a multipurpose,efficient,accurate and replicable national forest assessment.The design,operationalization and some key results of the process are presented.Methods:The BFI takes advantage of the latest and most well-accepted technological and methodological approaches.Importantly,it was designed through a collaborative process which drew from the experience and knowledge of multiple national and international entities.Overall,1781 field plots were visited,6400 households were surveyed,and a national land cover map for the year 2015 was produced.Innovative technological enhancements include a semi-automated segmentation approach for developing the wall-to-wall land cover map,an object-based national land characterisation system,consistent estimates between sample-based and mapped land cover areas,use of mobile apps for tree species identification and data collection,and use of differential global positioning system for referencing plot centres.Results:Seven criteria,and multiple associated indicators,were developed for monitoring progress towards sustainable forest management goals,informing management decisions,and national and international reporting needs.A wide range of biophysical and socioeconomic data were collected,and in some cases integrated,for estimating the indicators.Conclusions:The BFI is a new information source tool for helping guide Bangladesh towards a sustainable future.Reliable information on the status of tree and forest resources,as well as land use,empowers evidence-based decision making across multiple stakeholders and at different levels for protecting natural resources.The integrated socioeconomic data collected provides information about the interactions between people and their tree and forest resources,and the valuation of ecosystem services.The BFI is designed to be a permanent assessment of these resources,and future data collection will enable monitoring of trends against the current baseline.However,additional institutional support as well as continuation of collaboration among national partners is crucial for sustaining the BFI process in future. | Matieu Henry Zaheer Iqbal Kristofer Johnson Mariam Akhter Liam Costello Charles Scott Rashed Jalal Md.Akhter Hossain Nikhil Chakma Olaf Kuegler Hossain Mahmood Rajib Mahamud Mohammad Raqibul Hasan Siddique Khaled Misbahuzzaman Mohammad Main Uddin Mohammed Al Amin Farid Uddin Ahmed Gael Sola Md.Baktiar Siddiqui Luca Birigazzi Mahmudur Rahman Ilias Animon Saimunnahar Ritu Laskar Muqsudur Rahman Aminul Islam Heather Hayden Frida Sidik Mondal Falgoonee Kumar Rakibul Hassan Mukul Hossain Nishad Ariful Hoque Belal Asif Reza Anik Abdul Khaleque Md.Shaheduzzaman Syed Shahadat Hossain Tariq Aziz Md.Tauhidor Rahaman Ruhul Mohaiman Patrick Meyer Purnata Chakma A.Z.M.Manzoor Rashid Sourav Das Shrabanti Hira Mohammed Jashimuddin Mohammad Mahfuzur Rahman Karl Wurster Sarder Nasir Uddin Abul Kalam Azad S.M.Zahirul Islam Laurent Saint-André | 2021 | Forest Ecosystems2021，8，1： | 0 |
| 6 | Coal rib response during bench mining: A case study显示文摘In 2016, room-and-pillar mining provided nearly 40% of underground coal production in the United States.Over the past decade, rib falls have resulted in 12 fatalities, representing 28% of the ground fall fatalities in U.S.underground coal mines.Nine of these 12 fatalities(75%) have occurred in room-andpillar mines.The objective of this research is to study the geomechanics of bench room-and-pillar mining and the associated response of high pillar ribs at overburden depths greater than 300 m.This paper provides a definition of the bench technique, the pillar response due to loading, observational data for a case history, a calibrated numerical model of the observed rib response, and application of this calibrated model to a second site. | Morgan M.Sears John Rusnak Mark Van Dyke Gamal Rashed Khaled Mohamed Michael Sloan | 2018 | International Journal of Mining Science and Technology2018，28，1： | 0 |
| 7 | Preliminary rib support requirements for solid coal ribs using a coal pillar rib rating(CPRR)显示文摘Researchers from the National Institute for Occupational Safety and Health(NIOSH)are developing a coal pillar rib rating(CPRR)technique to measure the integrity of coal ribs.The CPRR characterizes the rib composition and evaluates its impact on the inherent stability of the coal ribs.The CPRR utilizes four parameters:rib homogeneity,bedding condition,face cleat orientation with respect to entry direction,and rib height.All these parameters are measurable in the field.A rib data collecting procedure and a simple sheet to calculate the CPRR were developed.The developed CPRR can be used as a rib quality mapping tool in underground coal mines and to determine the potential of local rib instabilities and support requirements associated with overburden depth.CPRR calculations were conducted for 22 surveyed solid coal ribs,mainly composed of coal units.Based on this study,the rib performance was classified into four categories.A preliminary minimum primary rib support density(PRSD)line was obtained from these surveyed cases.Two sample cases are presented that illustrate the data collection form and CPRR calculations. | Khaled Mohamed Mark Van Dyke Gamal Rashed Morgan MSears Robert Kimutis | 2021 | International Journal of Mining Science and Technology2021，31，1： | 0 |
| 8 | A coal rib monitoring study in a room-and-pillar retreat mine显示文摘The National Institute for Occupational Safety and Health(NIOSH)conducted a comprehensive monitoring program in a room-and-pillar mine located in Southern Virginia.The deformation and the stress change in an instrumented pillar were monitored during the progress of pillar retreat mining at two sites of different geological conditions and depths of cover.The main objectives of the monitoring program were to better understand the stress transfer and load shedding on coal pillars and to quantify the rib deformation due to pillar retreat mining;and to examine the effect of rib geology and overburden depth on coal rib performance.The instrumentation at both sites included pull-out tests to measure the anchorage capacity of rib bolts,load cells mounted on rib bolts to monitor the induced loads in the bolts,borehole pressure cells(BPCs)installed at various depths in the study pillar to measure the change in vertical pressure within the pillar,and roof and rib extensometers installed to quantify the vertical displacement of the roof and the horizontal displacement of the rib that would occur during the retreat mining process.The outcome from the monitoring program provides insight into coal pillar rib support optimization at various depths and geological conditions.Also,this study contributes to the NIOSH rib support database in U.S coal mines and provides essential data for rib support design. | Gamal Rashed Khaled Mohamed Robert Kimutis | 2021 | International Journal of Mining Science and Technology2021，31，1： | 0 |
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