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Processing of measurement while drilling data for rock mass characterization

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International Journal of Mining Science and Technology 2016年第6期26卷 989-994页

作者： Babaei Khorzoughi Mohammad hall robert Norman B.Keevil Institute of Mining Engineering University of British Columbia School of Mining and Petroleum Engineering University of Alberta

The information extracted from monitoring of rotary blasthole drills helps to optimize the overall mining operation. Rock hardness, drillability, blastability and specific energy of drilling are examples of parameters that have been estimated in the past using measurement while drilling techniques. In order to be able to properly utilize measurement while drilling techniques, it is important to properly collect, analyze and interpret extracted data. This paper deals with processing of measurement while drilling data such as rate of penetration, rotary speed, rotary torque and pulldown force collected from rotary blasthole *** methods are discussed to calculate a true rate of penetration which is the most important monitored drill variable for use in rock mass characterization. Then specific energy of drilling is defined and calculated based on electrical and mechanical inputs and the results are compared. The results show that specific energy of drilling can be estimated using the drill's primary drive systems' electrical responses with good accuracy when compared to values based on mechanical inputs.

关键词： Measurement while drilling Rotary blasthole drill Specific energy Rate of penetration

Rock fracture density characterization using measurement while drilling(MWD) techniques

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International Journal of Mining Science and Technology 2018年第6期28卷 859-864页

作者： Mohammad Babaei Khorzoughi robert hall Derek Apel Norman B.Keevil Institute of Mining Engineering University of British Columbia School of Mining and Petroleum Engineering University of Alberta

Accurate determination of rock mass properties is a critical part of open-pit mine planning activities to enable more prescriptive blast designs to achieve improved loading and hauling and downstream process efficiency. Better and more accurate blast practice that delivers enhanced outcomes(better fragmentation, improved diggability, less dilution, etc.) is a critical and fundamental element of being able to achieve an effective Mine-Mill approach at a mining operation. Based on previous work, it has been demonstrated that an accurate representation of the rock mass properties can be obtained from the analysis of variations in blasthole drill performance as derived from measurement while drilling(MWD) systems when using tricone bits. This paper further investigates how monitored rate of penetration,pulldown force, rotary torque, rotary speed and bailing air pressure responses can be used to determine the presence of open and partially open fractures having varying dip angles. Based on a correlation of geophysically measured fracture logs and monitored drill performance variables in the same blastholes, the results show that the latter responses can accurately determine open versus closed fractures. The results also identified that variations in rate of penetration and rotary torque show the most sensitivity in the presence of open fractures that intersect a vertical blasthole at near orthogonal angles.

关键词： Measurement while drilling Fractures Rotary blasthole drill Drill performance variables Fracture frequency Logging

Performance evaluation of near real-time condition monitoring in haul trucks

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International Journal of Mining Science and Technology 2020年第6期30卷 909-915页

作者： Hemanth Reddy Alla robert hall Derek B.Apel University of Alberta Edmonton T6G 2H5Canada

Strategic maintenance plays a key role in ensuring high availability and utilization of the haul trucks,and as equipment began to grow more complex towards the end of the 20th century,there was a need for a proactive maintenance strategy,which led to the development of condition-based *** condition monitoring(RTCM)is the ability to perform condition monitoring in real-time and has the ability to alert maintenance and operations of abnormal *** alarms can be used as an indication leading to a problem,and if a suitable corrective action is initiated in time,it could result in significant savings of equipment downtime and repair *** study aims to compare some maintenance performance indicators prior to and after implementation of RTCM strategy at a mine site using some tests of statistical *** study also indicated the presence of seasonality in the data,and thus the data was deseasonalized and detrended prior to being subjected to the statistical ***,the results indicated that RTCM strategy has proven to be successful in improving the availability for some of the failure categories chosen in this study.

关键词： Haul trucks Real-time condition monitoring Performance indicators

Plio-Pleistocene sedimentation and palaeogeographic reconstruction in the Poso Depression,Central Sulawesi,Indonesia:from a sea channel to a land bridge

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Journal of Palaeogeography 2023年第3期12卷 331-357页

作者： Abang Mansyursyah Surya Nugraha Ramadhan Adhitama Adam D.Switzer robert hall Earth Observatory of Singapore Nanyang Technological University50 Nanyang Ave.639798Singapore Fakultas Teknologi Kebumian dan Energi Universitas TrisaktiKampus A Gedung DJI.Kyai Tapa No.1GrogolJakarta 11441Indonesia Asian School of the Environment Nanyang Technological University50 Nanyang Ave.639798Singapore SE Asia Research Group Department of Earth SciencesRoyal Holloway University of LondonEghamSurreyTW200EXUK

The Poso Depression provides a record of Plio-Pleistocene environments and palaeogeography of Central ***-based sedimentological and provenance studies suggest that during the Pliocene the Poso Depression was a sea channel connecting Gorontalo and Bone bays formed in an asymmetric *** Pliocene history began with deposition of the Puna Formation with fan deltas at the eastern basin margin and channel complexes in the deep-water basin further *** of light and heavy minerals indicate the main sediment source was ultrabasic rocks in East Sulawesi with minor and intermittent magmatic and metamorphic input from West ***,in the Middle to Late Pliocene,carbonates of the Poso Formation accumulated on the eastern basin *** are unconformably overlain by shallow marine glaucophane-rich siliciclastics of the Pleistocene Lage Formation that are associated with the rapid exhu-mation and uplift of the Pompangeo metamorphic *** uplift led to the development of a land bridge connecting western and eastern *** terrane evolution favoured increasing the area of exposed land due to rapid tectonic uplift,which when combined with the tropical climate,contributed to faunal speciation and dispersal in Sulawesi.

关键词： Palaeogeography Poso Sulawesi Sedimentation history Provenance

Numerical modeling for rockbursts:A state-of-the-art review

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Journal of Rock Mechanics and Geotechnical Engineering 2021年第2期13卷 457-478页

作者： Jun Wang Derek B.Apel Yuanyuan Pu robert hall Chong Wei Mohammadali Sepehri School of Mining and Petroleum Engineering University of AlbertaEdmontonAlbertaT6G 2R3Canada State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing UniversityChongqing400044China

As the depth of excavation increases,rockburst becomes one of the most serious geological hazards damaging equipment and facilities and even causing fatalities in mining and civil *** has forced researchers worldwide to identify different methods to investigate rockburst-related ***,some problems,such as the mechanisms and the prediction of rockbursts,continue to be studied because rockburst is a very complicated phenomenon influenced by the uncertainty and complexity in geological conditions,in situ stresses,induced stresses,*** modeling is a widely used method for investigating *** date,great achievements have been made owing to the rapid development of information technology(IT)and computer ***,it is necessary and meaningful to conduct a review of the current state of the studies for rockburst numerical *** this paper,the categories and the origin of different numerical approaches employed in modeling rockbursts are reviewed and the current usage of various numerical modeling approaches is investigated by a literature ***,a state-of-the-art review is implemented to investigate the application of numerical modeling in the mechanism study,and prediction and prevention of *** main achievements and problems are ***,this paper discusses the limitations and the future research of numerical modeling for *** approach is proposed to provide researchers with a systematic and reasonable numerical modeling framework.

关键词： Rockburst Numerical modeling Rockburst mechanism Dynamic modeling

Metabolic responses of Eucalyptus species to different temperature regimes

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Journal of Integrative Plant Biology 2018年第5期60卷 397-411页

作者： Joao Benhur Mokochinski Paulo Mazzafera Alexandra Christine Helena Frankland Sawaya Roland Mumm Ric Cornelis Hendricus de Vos robert David hall Department of Plant Biology Institute of Biology State University of CampinasUNICAMP Bioscience Wageningen Plant Research Wageningen University and Research Faculty of Pharmaceutical Science State University of CampinasUNICAMP Laboratory of Plant Physiology Wageningen University and Research

Species and hybrids of Eucalyptus are the world＇s most widely planted hardwood trees. They are cultivated across a wide range of latitudes and therefore environmen- tal conditions. In this context, comprehensive metabolo- mics approaches have been used to assess how different temperature regimes may affect the metabolism of three species of Eucalyptus, E. dunnii, E. grandis and E. pellita. Young plants were grown for 53 d in the greenhouse and then transferred to growth chambers at 10℃, 20℃ or 30℃ for another 7 d. In all three species the leaf chlorophyll content was positively correlated to temperature, and in E. pellita the highest temperature also resulted in a significant increase in stem biomass. Comprehensive metabolomics was performed using untargeted gas chromatography mass spectrometry （GC-MS） and liquid chromatography （LC）-MS. This approach enabled the comparison of the relative abundance of 88 polar primary metabolites from GC-MS and 625 semi-polar secondary metabolites from LC-MS. Using principal components analysis, a major effect of tempera- ture was observed in each species which was larger than that resulting from the genetic background. Compounds mostly affected by temperature treatment were subsequently selected using partial least squares discriminant analysis and were further identified. These putative annotations indicated that soluble sugars and several polyphenols, including tannins, triterpenes and alkaloids were mostly influenced.

关键词： Uwe Sonnewald Friedrich-Alexander University Germany

Linking Management and Riparian Physical Functions to Water Quality and Aquatic Habitat

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Journal of Water Resource and Protection 2016年第8期8卷 797-815页

作者： Donald F. Kozlowski robert K. hall Sherman R. Swanson Daniel T. Heggem USDA Forest Service Beckwourth Ranger District Plumas National Forest Blairsden CA USA USEPA Region IX WTR2 San Francisco CA USA Natural Resources & Environmental Sciences University of Nevada Reno NV USA USEPA Office of Research & Development NERL Environmental Sciences Division Las Vegas NV USA

Stream and wetland riparian areas are able to sustain a state of resiliency based on the ecosystem’s ability to attain the functions of its ecological potential. This resiliency allows an area to provide and produce desired and valued water quality and aquatic habitat ecosystem services. Maintaining healthy aquatic and riparian habitats depends on “management” allowing for, or facilitating natural recovery of riparian functions. Altering grazing management practices in Maggie Creek lead to changes in riparian functionality, water quality, and aquatic habitat. Maggie Creek basin, historically renowned for its fishery, is one of only a few watersheds in Nevada capable of supporting Lahontan Cutthroat Trout (LCT) (Oncorhynchus clarkia ssp. Henshawi) meta-populations. Prior to 1993, the majority of Maggie Creek was grazed by cattle throughout the growing season. Decades of intensive grazing, water development, and road construction degraded aquatic and riparian habitats. By the early 1990’s, a majority of the Maggie Creek watershed was rated as nonfunctional or functional-at-risk condition with unstable banks, channel incision, loss of riparian vegetation, wide shallow channels, excessive erosion and deposition, reduced stream flows, and increased water temperatures. As mitigation for their 1993 South Operations Area Project mine dewatering, Newmont Mining Company, in cooperation with the Elko District Bureau of Land Management (BLM) and the Elko Land and Livestock Company, developed the Maggie Creek Watershed Restoration Project to enhance LCT habitat. The project was developed to enhance 82 miles of stream, 2000 acres of riparian habitat and 40,000 acres of upland watershed primarily through prescriptive livestock management. Beginning in 1994, grazing systems were implemented for portions of the perennial/intermittent streams. This greatly reduced the frequency and duration of hot season grazing on Maggie Creek and its tributaries. The objective of this paper is to c

关键词： Ecosystem Function Water Quality Non-Point Source Proper Functioning Condition

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病态科学

世界科学 1991年第6期 49-55页

作者： Irving Langmuir robert N.hall 赵乐静

“病态科学”一文发表在1989年美国物理学会的刊物《今日物理》第10期上.本刊特将此文翻译摘登,以飨国内的读者.该文自发表后,已引起不少反响,不少人认为朗缪提出了科学研究中一个重要的社会现象,而且还联系了当前科学研究中的实际,但... 详细信息

“病态科学”一文发表在1989年美国物理学会的刊物《今日物理》第10期上.本刊特将此文翻译摘登,以飨国内的读者.该文自发表后,已引起不少反响,不少人认为朗缪提出了科学研究中一个重要的社会现象,而且还联系了当前科学研究中的实际,但也有人担心这会影响科学上不同学派之间的正常争论.我们认为,必须将科学研究过程中不可避免的错误和病态科学区分开来.不能将一切错误都归结为病态科学.但另一方面,从大量科学史中的例子,包括我国科学发展中出现的事例来看,病态科学提出的确是一类真实的并且产生影响的社会现象.正视它,研究它,并从中吸取必要的教训,正是为了繁荣我国的科学事业.而引起国内读者对这一问题的注意,正是编者发表此文的目的.

关键词：病态科学同位素巴恩斯戴维斯飞碟航空器电子速度玻尔轨道赫尔阿里玻尔理论量子论惠特尼刘易斯

Differential equations / Paul Blanchard, robert L. Devaney, Glen R. hall. 2nd ed.

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