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Performance analysis and design of loitering munitions: A comprehensive technical survey of recent developments

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Defence Technology（防务技术） 2022年第3期18卷 325-343页

作者： mark Voskuijl Faculty of Military Sciences Netherlands DefenceAcademyDenHelderThe Netherlands

Loitering munitions are increasingly used in armed *** extensive database of loitering munitions is developed based on information available in the public *** database includes dimensions,weights,and performance parameters such as flight endurance and communication *** upon this dataset,6 categories of loitering munitions are identified and statistical trends in the form of equations are provided for each *** statistical trends are supported by aircraft performance theory tailored to loitering munitions ***,the combination of the database,statistical trends and aircraft performance theory can be used to analyse the flight performance and design considerations of new loitering munitions of which only limited non-technical information is available in the public domain such as pictures and news *** on the statistical trends and aircraft performance theory it is concluded that for long range applications,the preferred design solution is the conventional *** cruciform configuration is beneficial in case precision flight path control is of prime *** tandem wing configuration combines the benefits of a canister launch and relatively high aspect ratio wings suitable for long range ***,the delta wing design provides a large internal volume and a high terminal attack *** example case studies are included to illustrate the flight performance capabilities of two types of loitering munitions used in the current conflict in Yemen(a long range conventional design and a delta wing configuration).

关键词： Loitering munition Unmanned aerial vehicle Flight performance Design

An updated empirical model for ground control in *** coal mines

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International Journal of Mining Science and Technology 2021年第2期31卷 163-174页

作者： Christopher mark Mine Safety and Health Administration PittsburghPA 15217USA

Multiple seam interactions are a major source of ground instability in several *** methods are well suited for this problem,because while the mechanics multiple seam interactions are very complex and poorly understood,many mining case histories are available for *** study makes use of an updated database that includes 356 multiseam case histories,including 67 unsuccessful *** paper describes in detail the process used to design the study,collect the data,conduct the statistical analysis,and develop the quantitative *** model can be used for mine planning in multiple seam situations,and has been made available as a module within the Analysis of Coal Pillar Stability(ACPS)computer program.

关键词： Underground Coal Multiseam Ground control Pillar design Empirical

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三次样条与求积法则之间的联系

数学译林 2024年第1期43卷 90-92页

作者： mark H.Holmes 陆柱家(译) 陆昱(校) 不详

我们由三次样条函数的准确积分可以得到一个复合积分法则.反过来,这个方法可以推导出样条的端点条件,以得到高阶的求积公式.

关键词：三次样条求积公式求积法积分法则端点

Evolution of airports from a network perspective--An analytical concept

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Chinese Journal of Aeronautics 2017年第2期30卷 513-522页

作者： mark Azzam German Aerospace Center -DLR 53227 Bonn Germany

Analyzing airports＇ role in global air transportation and monitoring their development over time provides an additional perspective on the dynamics of network *** order to understand the different roles airports can play in the network an integrated and multidimensional approach is ***,an approach to airport classification through hierarchical clustering considering several parameters from network theory is presented in this *** applying a 29 year record of global flight data and calculating the conditional transition probabilities the results are displayed as an evolution graph similar to a discrete-time markov *** this analytical concept the meaning of airports is analyzed from a network perspective and a new airport taxonomy is *** presented methodology allows tracking the development of airports from certain categories into others over *** show that airports of equal classes run through similar stages of development with a limited number of alternatives,indicating clear evolutionary *** from giving an overview of the results the paper illustrates the exact data-driven approach and suggests an evaluation *** methodology can help the public and industry sector to make informed strategy decisions when it comes to air transportation infrastructure.

关键词： Airport classification Air transportation Cluster analysis Complexity science Network development Network science

Biomimicry and Theory of Structures-Design Methodology Transfer from Trees to Moment Frames

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Journal of Bionic Engineering 2014年第4期11卷 638-648页

作者： mark Grigorian MGA Structural Engineering Inc. 111 N. Jackson St. Glendale CA. 91206 USA

Currently, there are only three classical and a handful of emerging design methodologies available to structural engineers worldwide. None of these methodologies can explain the design concepts involved in the realization of natural structures such as trees, nor can they fully address the design needs of contemporary engineering structures. The recently developed Performance Control （PC） incorporates both the essence of the classical concepts and the newer procedures and addresses the observed performance of the structure during its known history of loading, PC attempts to mimic nature by applying the known theories of structures to the design of case-specific frameworks, rather than investigating their results for compliance against prescriptive criteria. Parametric examples have been provided to illustrate the applications of the conceptual design similarities between trees and manmade moment frames. It has been shown that an understanding of the structural performance of trees can enhance the structural design of moment frames, and that bioinspired PC can lead to minimum weight moment frames under lateral loading. The analogous performances of the natural and manmade structures may help explain the structural response of trees to similar loading scenarios.

关键词： performance control biomimetics trees moment frames lateral loading

Coal bursts that occur during development: A rock mechanics enigma

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International Journal of Mining Science and Technology 2018年第1期28卷 35-42页

作者： Christopher mark Safety and Health Administration Pittsburgh 15236USA

Coal bursts are typically associated with highly stressed *** bursts occur during retreat mining(longwall mining or pillar recovery) in highly stressed locations like the tailgate corner of the longwall *** are associated with multiple seam ***, a small but significant percentage of coal bursts have occurred during development or in outby locations unaffected by active *** development bursts have been relatively small, but some have been highly *** theory of coal bursts can be complete if it does not account for this type of *** paper focusses on the development mining coal burst experience in the US, putting it into the context of the entire US coal burst *** first documented development coal burst occurred almost exactly 100 years ago during slope drivage at the Sunnyside Mine in *** subsequently had a long history of bursts, mainly during retreat mining but also during *** Colorado mines have also experienced multiple development ***, but by no means all, of the development bursts in these western US coalfields have been associated with known *** the Central Appalachian coalfields, most development bursts have occurred in multiple seam *** some of these cases, however, there was no retreat mining in either *** paper closes with some lessons from this history, with implications for preventing such events in the future.

关键词： Coal Underground Ground control Bursts Multiple seam

Sedation reversal trends at outpatient ambulatory endoscopic center vs in-hospital ambulatory procedure center using a triage protocol

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World Journal of Gastrointestinal Endoscopy 2024年第7期16卷 413-423页

作者： Saqib Walayat Peter Stadmeyer Azfar Hameed Minahil Sarfaraz Paul Estrada mark Benson Anurag Soni Patrick Pfau Paul Hayes Brittney Kile Toni Cruz Deepak Gopal Department of Gastroenterology University of IllinoisPeoriaIL 61605United States Department of Gastroenterology University of WisconsinMadisonWI 53792United States Department of Internal Medicine Texas Health DentonDentonTX 76201United States Department of Internal Medicine Allama Iqbal Medical CollegeLahore 042Pakistan Department of Gastroenterology Texas Tech University Health Services CenterEl PasoTX 79911United States Department of Gastroenterology and Hepatology University of WisconsinMadisonWI 53705United States Finance Business Partners UW Health University of WisconsinMadisonWI 53792United States UW Health Digestive Health Center Endoscopy University of WisconsinMadisonWI 53792United States Division of Gastroenterology and Hepatology Department of MedicineUniversity of Wisconsin Hospitals and ClinicsMadisonWI 53705United States

BACKGROUND Routine outpatient endoscopy is performed across a variety of outpatient settings.A known risk of performing endoscopy under moderate sedation is the potential for over-sedation,requiring the use of reversal *** needs to be reported on rates of reversal across different outpatient *** academic tertiary care center utilizes a triage tool that directs higher-risk patients to the in-hospital ambulatory procedure center(APC)for their ***,we report data on outpatient sedation reversal rates for endoscopy performed at an inhospital APC vs at a free-standing ambulatory endoscopy digestive health center(AEC-DHC)following risk stratification with a triage *** To observe the effect of risk stratification using a triage tool on patient outcomes,primarily sedation reversal *** We observed all outpatient endoscopy procedures performed at AEC-DHC and APC from April 2013 to September *** were stratified to their respective sites using a triage *** evaluated each procedure for which sedation reversal with flumazenil and naloxone was *** and characteristics recorded include patient age,gender,body mass index(BMI),American Society of Anesthesiologists(ASA)classification,procedure type,and reason for sedation *** There were 97366 endoscopic procedures performed at AEC-DHC and 22494 at the APC during the study *** these,17 patients at AEC-DHC and 9 at the APC underwent sedation reversals(0.017%vs 0.04%;P=0.06).Demographics recorded for those requiring reversal at AEC-DHC vs APC included mean age(53.5±21 vs 60.4±17.42 years;P=0.23),ASA class(1.66±0.48 vs 2.22±0.83;P=0.20),BMI(27.7±6.7 kg/m^(2) vs 23.7±4.03 kg/m^(2);P=0.06),and female gender(64.7%vs 22%;P=0.04).The mean doses of sedative agents and reversal drugs used at AEC-DHC vs APC were midazolam(5.9±1.7 mg vs 8.9±3.5 mg;P=0.01),fentanyl(147.1±49.9μg vs 188.9±74.1μg;P=0.10),flumazenil(0.3±0.18μg vs 0.17±0.17μg;P=0.13)and naloxo

关键词： Ambulatory care Conscious sedation Endoscopy Colonoscopy Risk assessment Risk factors

Validity,Reliability,and Measurement Invariance of the Thai Smartphone Application-Based Addiction Scale and Bergen Social Media Addiction Scale

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International Journal of Mental Health Promotion 2024年第4期26卷 293-302页

作者： Kamolthip Ruckwongpatr Chirawat Paratthakonkun Usanut Sangtongdee Iqbal Pramukti Ira Nurmala Kanokwan Angkasith Weena Thanachaisakul Jatuphum Ketchatturat mark DGriffiths Yi-Kai Kao Chung-Ying Lin Institute of Allied Health Sciences College of MedicineNational Cheng Kung UniversityTainan701401Taiwan College of Sports Science and Technology Mahidol UniversityNakhon Pathom73170Thailand Department of Forensic Science Royal Police Cadet AcademyNakhon Pathom73110Thailand School of Computing Engineeringand Digital TechnologyTeesside UniversityMiddlesbroughUK Faculty of Nursing Universitas PadjadjaranWest Java45363Indonesia Division of Health Promotion and Behavioral Sciences Faculty of Public HealthUniversitas AirlanggaSurabaya60115Indonesia Faculty of Education Chiang Mai UniversityChiang Mai50200Thailand Faculty of Education Khon Kaen UniversityKhon Kaen40002Thailand International Gaming Research Unit Psychology DepartmentNottingham Trent UniversityNottinghamNG14FQUK Division of Colorectal Surgery E-DA HospitalKaohsiung82445Taiwan College of Medicine National Cheng Kung UniversityTainan701401Taiwan Biostatistics Consulting Center National Cheng Kung University HospitalTainan701401Taiwan

Background:In recent years,there has been increased research interest in both smartphone addiction and social media addiction as well as the development of psychometric instruments to assess these ***,there is a lack of psychometric evaluation for instruments assessing smartphone addiction and social media addiction in *** present study evaluated the psychometric properties and gender measurement invariance of the Thai version of the Smartphone Application-Based Addiction Scale(SABAS)and Bergen Social Media Addiction Scale(BSMAS).Method:A total of 801 Thai university students participated in an online survey from January 2022 to July 2022 which included demographic information,SABAS,BSMAS,and the Internet Gaming Disorder Scale-Short Form(IGDS9-SF).Results:Confirmatory Factor Analyses(CFAs)found that both the SABAS and BSMAS had a one-factor *** demonstrated adequate psychometric properties of both instruments and also supported measurement invariance across ***,scores on the SABAS and BSMAS were correlated with scores on the ***:The results indicated that the SABAS and BSMAS are useful psychometric instruments for assessing the risk of smartphone addiction and social media addiction among Thai young adults.

关键词： Factor analysis smartphone addiction social media addiction smartphone application-based addiction scale bergen social media addiction scale psychometric validation

Prehospital transdermal glyceryl trinitrate for ultra- acute ischaemic stroke: data from the RIGHT- 2 randomised sham- controlled ambulance trial

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Stroke & Vascular Neurology 2024年第1期9卷 38-49,I0035-I0046页

作者： Jason Philip Appleton Lisa J Woodhouse Craig S Anderson Sandeep Ankolekar Lesley Cala mark Dixon Timothy J England Kailash Krishnan Grant Mair Keith W Muir John Potter Christopher I Price Marc Randall Thompson G Robinson Christine Roffe Else C Sandset Jeffrey L Saver Angela Shone Aloysius Niroshan Siriwardena Joanna M Wardlaw Nikola Sprigg Philip M Bath Stroke University Hospitals Birmingham NHS Foundation TrustBirminghamUK Institute of Applied HealthResearch University of Birmingham College of Medical and Dental SciencesBirminghamUK Stroke Trials Unit Mental Health and Clinical NeurosciencesUniversity of NottinghamNottinghamUK Faculty of Medicine The George Institute for Global HealthSydneyNew South WalesAustralia The George Institute China at Peking University Health Science Center BeijingChina Neurology Royal Prince Alfred HospitalSydney Health PartnersSydneyNew South WalesAustralia Department of Neurology King's College Hospital NHS Foundation TrustLondonUK Faculty of Health and Medical Sciences University of Western AustraliaCrawleyWestern AustraliaAustralia East Midlands Ambulance Service NHS Trust NottinghamUK Stroke Queen's Medical CentreNottingham University Hospitals NHS TrustNottinghamUK Centre for Clinical Brain Sciences Dementia Research InstituteUniveristy of EdinburghEdinburghUK Institute of Neurology and Psychology University of GlasgowGlasgowUK Bob Champion Research and Education Building University of East AngliaNorwichUK Institute of Neuroscience Newcastle UniversityNewcastle upon TyneUK Department of Neurology Leeds Teaching Hospitals NHS TrustLeedsUK Department of Cardiovascular Sciences and NIHR Leicester Biomedical Research Centre University of LeicesterLeicesterUK Stroke Research in Stoke Institute for Science and Technology in MedicineKeele UniversityStoke-on TrentUK Department of Neurology Oslo University HospitalOsloNorway Research and Development Norwegian Air Ambulance FoundationOsloNorway Department of Neurology and Comprehensive Stroke Center David Geffen School of MedicineUCLALos AngelesCaliforniaUSA Research and Graduate Services University of NottinghamNottinghamUK Community and Health Research Unit University of LincolnLincolnUK

Background The effect of transdermal glyceryl trinitrate(GTN,a nitrovasodilator)on clinical outcome when administered before hospital admission in suspected stroke patients is ***,we assess the safety and efficacy of GTN in the prespecified subgroup of patients who had an ischaemic stroke within the Rapid Intervention with Glyceryl trinitrate in Hypertensive stroke Trial-2(RIGHT-2).Methods RIGHT-2 was an ambulance-based multicentre sham-controlled blinded-endpoint study with patients randomised within 4hours of *** primary outcome was a shift in scores on the modified Rankin scale(mRS)at day *** outcomes included death;a global analysis(Wei-Lachin test)containing Barthel Index,EuroQol-5D,mRS,telephone interview for cognitive status-modified and Zung depression scale;and neuroimaging-determined‘brain frailty’*** were reported as n(%),mean(SD),median[IQR],adjusted common OR(acOR),mean difference or Mann-Whitney difference(MWD)with 95%*** 597 of 1149(52%)patients had a final diagnosis of ischaemic stroke;age 75(12)years,premorbid mRS>2107(18%),Glasgow Coma Scale 14(2)and time from onset to randomisation 67[45,108]***‘brain frailty’was common:median score 2[2,3](range 0–3).At day 90,GTN did not influence the primary outcome(acOR for increased disability 1.15,95%CI 0.85 to 1.54),death or global analysis(MWD 0.00,95%CI-0.10 to 0.09).In subgroup analyses,there were non-significant interactions suggesting GTN may be associated with more death and dependency in participants randomised within 1hour of symptom onset and in those with more severe *** In patients who had an ischaemic stroke,ultra-acute administration of transdermal GTN in the ambulance did not improve clinical outcomes in a population with more clinical and radiological frailty than seen in previous in-hospital *** IS ALREADY KNOWN ON THIS TOPIC⇒Transdermal glyceryl trinitrate(GTN)was associat-ed with less death and dependency in those w

关键词： Glasgow nitrate random