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Exteriorized colon anastomosis for unprepared bowel: An alternative to routine colostomy
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作者 Sami K Asfar Hilal M Al-Sayer Talib H Juma 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第23期3215-3220,共6页
AIM: To see the possibility of avoiding routine colostomy in patients presenting with unprepared bowel. METHODS: The cohort is composed of 103 patients, of these, 86 patients presented as emergencies (self- inflected ... AIM: To see the possibility of avoiding routine colostomy in patients presenting with unprepared bowel. METHODS: The cohort is composed of 103 patients, of these, 86 patients presented as emergencies (self- inflected and iatrogenic colon injuries, stab wounds and blast injury of the colon, volvulus sigmoid, obstructing left colon cancer, and strangulated ventral hernia). Another 17 patients were managed electively for other colon pathologies. During laparotomy, the involved segment was resected and the two ends of the colon were brought out via a separate colostomy wound. One layer of interrupted 3/0 silk was used for colon anastomosis. The exteriorized segment was immediately covered with a colostomy bag. Between the 5th and 7th postoperative day, the colon was easily dropped into the peritoneal cavity. The defect in the abdominal wall was closed with interrupted nonabsorbable suture. The skin was left open for secondary closure. RESULTS: The mean hospital stay (± SD) was 11.5 ± 2.6 d (8-20 d). The exteriorized colon was successfully dropped back into the peritoneal cavity in all patients except two. One developed a leak from oesophago- jejunostomy and from the exteriorized colon. She subsequently died of sepsis and multiple organ failure (MOF). In a second patient the colon proximal to the exteriorized anastomosis prolapsed and developed severe serositis, an elective ileo-colic anastomosis (to the left colon) was successfully performed. CONCLUSION: Exteriorized colon anastomosis is simple, avoids the inconvenience of colostomy and can be an alternative to routine colostomy. It is suitable where colostomy is socially unacceptable or the facilities and care is not available. 展开更多
关键词 COLOSTOMY exteriorized colon Colon injury Colon anastomosis Unprepared colon Obstructing colon cancer Volvulus sigmoid
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The circadian clock in enamel development
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作者 Ke Wu Xiaochan Li +3 位作者 Yunyang Bai Boon Chin Heng Xuehui Zhang Xuliang Deng 《International Journal of Oral Science》 SCIE CAS CSCD 2024年第3期371-380,共10页
Circadian rhythms are self-sustaining oscillations within biological systems that play key roles in a diverse multitude of physiological processes.The circadian clock mechanisms in brain and peripheral tissues can osc... Circadian rhythms are self-sustaining oscillations within biological systems that play key roles in a diverse multitude of physiological processes.The circadian clock mechanisms in brain and peripheral tissues can oscillate independently or be synchronized/disrupted by external stimuli.Dental enamel is a type of mineralized tissue that forms the exterior surface of the tooth crown.Incremental Retzius lines are readily observable microstructures of mature tooth enamel that indicate the regulation of amelogenesis by circadian rhythms.Teeth enamel is formed by enamel-forming cells known as ameloblasts,which are regulated and orchestrated by the circadian clock during amelogenesis.This review will first examine the key roles of the circadian clock in regulating ameloblasts and amelogenesis.Several physiological processes are involved,including gene expression,cell morphology,metabolic changes,matrix deposition,ion transportation,and mineralization.Next,the potential detrimental effects of circadian rhythm disruption on enamel formation are discussed.Circadian rhythm disruption can directly lead to Enamel Hypoplasia,which might also be a potential causative mechanism of amelogenesis imperfecta.Finally,future research trajectory in this field is extrapolated.It is hoped that this review will inspire more intensive research efforts and provide relevant cues in formulating novel therapeutic strategies for preventing tooth enamel developmental abnormalities. 展开更多
关键词 ENAMEL CROWN EXTERIOR
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An impact sensitivity assessment method of spacecraft based on virtual exterior wall
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作者 Runqiang Chi Yuyan Liu +1 位作者 Diqi Hu Baojun Pang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期142-157,共16页
The impact sensitivity assessment of spacecraft is to obtain the probability of spacecraft encountering the OD/M(orbital debris or meteoroid),which is a prerequisite for survivability assessment of on-orbit spacecraft... The impact sensitivity assessment of spacecraft is to obtain the probability of spacecraft encountering the OD/M(orbital debris or meteoroid),which is a prerequisite for survivability assessment of on-orbit spacecraft.An impact sensitivity assessment method of spacecraft based on virtual exterior wall was proposed to improve the computational efficiency.This method eliminates determination of the outermost surface elements of the spacecraft before generating the debris rays,which are assumed to originate from a non-concave virtual wall that completely wraps the spacecraft.The Dist Mesh method was adopted for the generating of the virtual wall to ensure its mesh quality.The influences of the sizes,mesh densities,shapes of the virtual wall on the efficiency and accuracy were considered to obtain the best combination of the size and mesh density of the wall and spacecraft.The results of this method were compared with those of S3DE(Survivability of Spacecraft in Space Debris Environment),BUMPER,MDPANTO,ESABASE2/Debris to verify the feasibility of the method.The PCHIP(Piecewise Cubic Hermite Interpolating Polynomial)was used to fit the size vs.flux relationship of the space debris to acquire the impact probability of OD/M with arbitrary size on the spacecraft. 展开更多
关键词 Sensitivity OD/M SPACECRAFT Virtual exterior wall
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Research and development of 3PP coating steel pipes
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作者 FANG Wenqi MA Yuan HUI Linlin 《Baosteel Technical Research》 CAS 2024年第2期1-11,共11页
The industrial application of an exterior three-layer anticorrosive polypropylene coating system(3PP)on large-diameter(larger than Φ600 mm)steel pipes was developed using an experimental process simulation study and ... The industrial application of an exterior three-layer anticorrosive polypropylene coating system(3PP)on large-diameter(larger than Φ600 mm)steel pipes was developed using an experimental process simulation study and the optimization of raw materials inspection,steel pipe surface pretreatments,and water cooling control on a coating application process.The coating properties meet ISO standard 21809 on buried or submerged 3PP pipelines used in the petroleum and natural gas industries.Differential scanning calorimetry and X-ray diffraction were used to analyze the crystallinities and grain sizes of polypropylene(PP)top coats with different cooling rates.Increasing the melt cooling rate reduces the crystallinity and grain size of the PP top coat and enhances its strength and toughness. 展开更多
关键词 3PP steel pipe oil and gas pipelines cathodic disbondment polypropylene coatings exterior anticorrosive system
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Durian Time Ripe opportunity to export Malaysian durians to China
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作者 Guo Xixian 《China Report ASEAN》 2024年第6期22-24,共3页
Relentlessly high temperatures sweep across Malaysia to signal the arrival of summer.Facing a survival crisis,durian trees are eager to reproduce,and they blossom hastily,with white flowers quickly drooping down.More ... Relentlessly high temperatures sweep across Malaysia to signal the arrival of summer.Facing a survival crisis,durian trees are eager to reproduce,and they blossom hastily,with white flowers quickly drooping down.More than 100 days later,durian fruits featuring spiky exteriors and creamy flesh become ripe and fall from the trees,emitting a uniquely captivating aroma.This marks the arrival of durian season. 展开更多
关键词 FLOWERS Malaysia EXTERIOR
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SCIENCE AND TECHNOLOGY
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《China Today》 2024年第11期59-59,共1页
China Unveils Moon-Landing Spacesuit The China Manned Space Agency(CMSA)unveiled the exterior design of the country's moon-landing spacesuit for the first time on September 28,soliciting recommendations for its na... China Unveils Moon-Landing Spacesuit The China Manned Space Agency(CMSA)unveiled the exterior design of the country's moon-landing spacesuit for the first time on September 28,soliciting recommendations for its name from the public.Displayed on the third Spacesuit Technology Forum hosted by the China Astronaut Research and Training Center in southwest China's Chongqing Municipality,the white moon-landing spacesuit is decorated with red stripes. 展开更多
关键词 CHONGQING SOUTHWEST EXTERIOR
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THE SINGULAR LIMIT OF SECOND-GRADE FLUID EQUATIONS IN A 2D EXTERIOR DOMAIN
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作者 游小光 臧爱彬 《Acta Mathematica Scientia》 SCIE CSCD 2023年第3期1333-1346,共14页
In this paper, we consider the second-grade fluid equations in a 2D exterior domain satisfying the non-slip boundary conditions. The second-grade fluid model is a wellknown non-Newtonian fluid model, with two paramete... In this paper, we consider the second-grade fluid equations in a 2D exterior domain satisfying the non-slip boundary conditions. The second-grade fluid model is a wellknown non-Newtonian fluid model, with two parameters: α, which represents the length-scale,while ν > 0 corresponds to the viscosity. We prove that, as ν, α tend to zero, the solution of the second-grade fluid equations with suitable initial data converges to the one of Euler equations, provided that ν = o(α^(4/3)). Moreover, the convergent rate is obtained. 展开更多
关键词 second-grade fluid equations Euler equations exterior domain singular limit
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THE LINEAR SAMPLING METHOD FOR RECONSTRUCTING A PENETRABLE CAVITY WITH UNKNOWN EXTERNAL OBSTACLES
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作者 叶建国 严国政 《Acta Mathematica Scientia》 SCIE CSCD 2023年第2期751-776,共26页
We consider the interior inverse scattering problem for recovering the shape of a penetrable partially coated cavity with external obstacles from the knowledge of measured scattered waves due to point sources.In the f... We consider the interior inverse scattering problem for recovering the shape of a penetrable partially coated cavity with external obstacles from the knowledge of measured scattered waves due to point sources.In the first part,we obtain the well-posedness of the direct scattering problem by the variational method.In the second part,we establish the mathematical basis of the linear sampling method to recover both the shape of the cavity,and the shape of the external obstacle,however the exterior transmission eigenvalue problem also plays a key role in the discussion of this paper. 展开更多
关键词 inverse scattering mixed boundary value problem exterior transmission eigen-value interior measurements linear sampling method
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Experimental Study on Seismic Performance of SRUHSC⁃RC Frame Exterior Joints with Cyclic Loads
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作者 Wei Liu Jinqing Jia Jian Su 《Journal of Harbin Institute of Technology(New Series)》 CAS 2023年第3期32-44,共13页
SRUHSC⁃RC(Steel Reinforced Ultra High Strength Concrete⁃Reinforced Concrete)structures are used extensively in super high⁃rise buildings.However,it has obvious brittleness.Wrapping structural steel inside is a good wa... SRUHSC⁃RC(Steel Reinforced Ultra High Strength Concrete⁃Reinforced Concrete)structures are used extensively in super high⁃rise buildings.However,it has obvious brittleness.Wrapping structural steel inside is a good way to alleviate the brittleness problem.The purpose of this study is to investigate seismic behavior of SRUHSC⁃RC exterior joints on the basis of experimental results of eleven specimens under the reversed cyclic loading.The relationship among the force⁃displacement curve,ductility,energy dissipation property,strength degradation,stiffness degradation,the strains of steel bone and stirrup at the core area of the joint were analyzed based on the test results.It is shown that axial compression ratio and stirrup volumetric ratio have significant effects on the shear behavior of SRUHSC⁃RC frame exterior joints.The general requirement on the axial⁃load level and the amount of confinement stirrup for the joints in the design is suggested. 展开更多
关键词 exterior joints STEEL ultra⁃high strength DUCTILITY shear resistance
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Talk Shows on the Rise in China
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作者 CUI XIAOQIN 《China Today》 2023年第2期70-73,共4页
Whether it is a talk show or other forms of comedy art,the ultimate goal is to express a point of view.Laughter is just the exterior packaging of a talk show,and performers must have a critical spirit.“Inf luenced by... Whether it is a talk show or other forms of comedy art,the ultimate goal is to express a point of view.Laughter is just the exterior packaging of a talk show,and performers must have a critical spirit.“Inf luenced by some TV variety shows,talk shows have become quite popular in China during the past few years,and a growing number of audiences have begun to watch offline performances,”said Zhou Shenglong,founder of Kangaroo Comedy. 展开更多
关键词 SHOW EXTERIOR PACKAGING
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SEQUENTIAL DISPERSING DISTRIBUTION EFFECT OF AERIAL CLUSTER BOMB
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作者 陶如意 谭俊杰 +1 位作者 王浩 刘赟 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2012年第4期354-359,共6页
The sequential dispersing results of aerial cluster bomb are discussed. The ballistic model and the mod- el for impact point distribution of bullets are established. The main factors influencing impact point distribut... The sequential dispersing results of aerial cluster bomb are discussed. The ballistic model and the mod- el for impact point distribution of bullets are established. The main factors influencing impact point distribution are analyzed by numerical simulation. And the feasibility of improving distribution effect through sequential dis- persing is validated. Sequential dispersion and optimized airdrop parameters can help to achieve better battle effec- tiveness. 展开更多
关键词 aerial cluster bomb sequential dispersion exterior ballistic initial conditions of dispersing effect of distribution
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Influence of layout of scanners on intelligent mine scanning trails
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作者 李大勇 赵俊利 +1 位作者 王妍 王立君 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2016年第3期229-234,共6页
To expand scanning area and attack range without changing the inner structure of intelligent warhead, a new arrangement mode of the scanner for intelligent mine is proposed. The required coordinate systems are es... To expand scanning area and attack range without changing the inner structure of intelligent warhead, a new arrangement mode of the scanner for intelligent mine is proposed. The required coordinate systems are established firstly on the basis of advanced dynamics principle. and the exterior ballistics equations are deduced. Then the equations of scanning trails are established by the method of space analytic geometry. To get the scanning trails. the differential equations are transformed into discrete simulation model using the algorithm of fourth order Runge-Kutta and then are simulated using Matlab. Compared with the scanning trails obtained by the traditional layout of scanner, the scanning trails obtained by the proposed layout of scanner has larger horizontal range of scanning circle and bigger trarget acquisition probability. Therefore, the new arrangement mode of the scanner for intelligent mine can increase attack range. 展开更多
关键词 intelligent mine SCANNER scanning trails exterior ballistics
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Exploration on the Components and Landscape Factors of Railway Landscape
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作者 贺玉龙 《Journal of Landscape Research》 2009年第11期33-36,44,共5页
The components of railway landscape were analyzed,and the railway landscape was classified as railway interior and exterior landscape from the perspective of its characters.After analysis and summarization,the compone... The components of railway landscape were analyzed,and the railway landscape was classified as railway interior and exterior landscape from the perspective of its characters.After analysis and summarization,the components and contents of the railway landscape factors were put forward. 展开更多
关键词 RAILWAY LANDSCAPE INTERIOR LANDSCAPE EXTERIOR LANDSCAPE LANDSCAPE factor
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Exterior Quality and Physical Properties of Hongda Tobacco in Yunnan Province 被引量:6
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作者 薛红芬 胡魏耀 +3 位作者 王娟 徐安传 周丽娟 资文华 《Agricultural Science & Technology》 CAS 2012年第4期751-754,共4页
[Objective] The aim was to analyze the exterior quality and physical prop- erties of Hongda Tobacco in Yunnan Province, thus providing references for planting planning, technology and selection of raw materials. [Meth... [Objective] The aim was to analyze the exterior quality and physical prop- erties of Hongda Tobacco in Yunnan Province, thus providing references for planting planning, technology and selection of raw materials. [Method] Hongda C3F progenies were chosen from 24 villages and towns in Qujing, Kunming, Baoshan and Dali, and the concerning exterior quality and physical properties were analyzed through cluster analysis. [Result] The openness and width of C3F differed significantly among Qujing, Kunming, Baoshan and Dali. The thickness, stem content, equilibrium moisture con- tent extremely differed, and density and filling power varied significantly. Most physi- cal properties, such as equilibrium moisture content and density, of Dali Hongda were quite different from those in Qujing, Kunming and Baoshan, indicating that Dali Hongda enjoys special characteristics in physical properties. In addition, stem content in east, center and west areas of Yunnan Province differed significantly and Hongda in Yunnan could be classified into four species according to physical property. [Conclusion] The research has laid basis for planting planning, technology and raw mate- rials selection of Hongda tobacco. 展开更多
关键词 Hongda Exterior quality:Physical properties:Local characteristics
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DERIVATION ALGEBRAS OF THE MODULAR LIE SUPERALGEBRAS W AND S OF CARTAN-TYPE 被引量:32
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作者 张庆成 张永正 《Acta Mathematica Scientia》 SCIE CSCD 2000年第1期137-144,共8页
Let F be a field and char F = p > 3. In this paper the derivation algebras of Lie superalgebras W and S of Cartan-type over F are determined by the calculating method.
关键词 Lie superalgebra exterior algebra derivation algebra
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Sound Source Localisation for a High-Speed Train and Its Transfer Path to Interior Noise 被引量:12
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作者 Jie Zhang Xinbiao Xiao +1 位作者 Xiaozhen Sheng Zhihui Li 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2019年第4期168-183,共16页
Noise is one of the key issues in the operation of high-speed railways, with sound source localisation and its transfer path as the two major aspects. This study investigates both the exterior and interior sound sourc... Noise is one of the key issues in the operation of high-speed railways, with sound source localisation and its transfer path as the two major aspects. This study investigates both the exterior and interior sound source distribution of a high-speed train and presents a method for performing the contribution analysis of airborne sound with regard to the interior noise. First, both exterior and interior sound source locations of the high-speed train are identified through in-situ measurements. Second, the sound source contribution for di erent regions of the train and the relationships between the exterior and interior noises are analysed. Third, a method for conducting the contribution analysis of airborne sound with regard to the interior noise of the high-speed train is described. Lastly, a case study on the sidewall area is carried out, and the contribution of airborne sound to the interior noise of this area is obtained. The results show that, when the high-speed train runs at 310 km/h, dominant exterior sound sources are located in the bogie and pantograph regions, while main interior sound sources are located at the sidewall and roof. The interior noise, the bogie area noise and the sound source at the middle of the coach exhibit very similar rates of increase with increasing train speed. For the selected sidewall area, structure-borne sound dominates in most of the 1/3 octave bands. 展开更多
关键词 High-speed TRAIN INTERIOR noise SOUND transfer path Noise source identification EXTERIOR noise AIRBORNE SOUND
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RELATIONSHIP BETWEEN DEVELOPMENTS OF THE HUANGHE AND YONGDING RIVERS AND THE EVOLUTION OF THE FOSSIL LAKES OF THE CENOZOIC ERA IN THE DRAINAGE AREA 被引量:5
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作者 李容全 杨明川 《Chinese Geographical Science》 SCIE CSCD 1991年第3期40-53,共14页
The Huanghe and Yongding rivers were formed before the early and middle Pliocene epoch. Then they became interior rivers because of the appearance of interior fault lake basins at the end of the Pliocene epoch. The in... The Huanghe and Yongding rivers were formed before the early and middle Pliocene epoch. Then they became interior rivers because of the appearance of interior fault lake basins at the end of the Pliocene epoch. The interior flow period continued until the end of the early Pleistocene or the middle pf the Middle Pleistocene, and then they changed into the exterior rivers again till today. 展开更多
关键词 the Huanghe RIVER the Yongding RIVER DEVELOPMENTS of a RIVER exterior FLOW PERIOD interior FLOW PERIOD
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Measurement of bullet impact conditions using automated in-flight photography system 被引量:4
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作者 Ryan Decker Marco Duca Shawn Spickert-Fulton 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2017年第4期288-294,共7页
Knowledge of impact conditions is critical to evaluating the terminal impact performance of a projectile.For a small caliber bullet,in-flight velocity has been precisely measured for decades using detection screens,bu... Knowledge of impact conditions is critical to evaluating the terminal impact performance of a projectile.For a small caliber bullet,in-flight velocity has been precisely measured for decades using detection screens,but accurately quantifying the orientation of the bullet on a target has been more challenging.This report introduces the Automated Small-Arms Photogrammetry(ASAP)analysis method used to measure,model,and predict the orientation of a small caliber bullet before reaching an impact surface.ASAP uses advanced hardware developed by Sydor Technologies to record a series of infrared digital photographs.Individual images(four orthogonal pairs)are processed using computer vision algorithms to quantify the orientation of the projectile and re-project its precise position and orientation into a three-dimensional muzzle-fixed coordinate system.An epicyclic motion model is fit to the measured data,and the epicyclic motion is extrapolated to the target location.Analysis results are fairly immediate and may be reviewed during testing.Prove-out demonstrations have shown that the impact-angle prediction capability is less than six hundredths of a degree for the 5.56 mm ball round tested.Keywords:Yaw,Terminal ballistics,Exterior ballistics,Test&evaluation,Computer vision,Image processing,Angle of 展开更多
关键词 Terminal BALLISTICS EXTERIOR BALLISTICS Test & evaluation Computer vision Image processing Angle of ATTACK
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Control of exterior ballistic properties of spin-stabilized bullet by optimizing internal mass distribution 被引量:3
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作者 Janne Lahti Timo Sailaranta +1 位作者 Mikko Harju Kai Virtanen 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2019年第1期38-50,共13页
This paper introduces a novel approach for controlling the exterior ballistic properties of spin-stabilized bullets by optimizing their internal mass distributions. Specifically, the properties of interest are the bul... This paper introduces a novel approach for controlling the exterior ballistic properties of spin-stabilized bullets by optimizing their internal mass distributions. Specifically, the properties of interest are the bullets’ stability characteristics that are examined through dynamic and gyroscopic stability parameters.New analytical expressions for aerodynamic quantities are also derived to address the compressibility of air. These expressions are utilized in a bullet model that enables efficient computation of the stability parameters for a given mass distribution. The bullet model is used in the formulation of nonlinear optimization problems that provide optimal mass distributions with respect to given goals, i.e., desired stability characteristics. The bullet types investigated in this paper are a long range bullet and a limited range training bullet. In the optimization of the mass distribution of the long range bullet, the goal is that the bullet stays stable for as long as possible. The mass distribution of the training bullet is optimized such that the bullet is stable at launch but becomes unstable shortly afterwards. The global optimal solutions obtained with the new approach fulfill the desired stability characteristics better than currently used uniformly filled bullets. Overall, the optimization approach reveals a new goal focused philosophy for bullet design compared to current trial and error design practices. 展开更多
关键词 AERODYNAMICS BULLET EXTERIOR BALLISTICS Mass properties Optimization Stability
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Improved geologic surface approximation using a multiquadric method with additional constraints 被引量:2
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作者 SONG Xianfeng RUI Xiaoping +1 位作者 JU Yiwen YANG Yongguo 《Mining Science and Technology》 EI CAS 2010年第4期600-606,共7页
Geologic surface approximation is profoundly affected by the presence, density and location of scattered geologic input data. Many studies have recognized the importance of utilizing varied sources of information when... Geologic surface approximation is profoundly affected by the presence, density and location of scattered geologic input data. Many studies have recognized the importance of utilizing varied sources of information when reconstructing a surface. This paper presents an improved geologic surface approximation method using a multiquadric function and borehole data. Additional information, i.e., inequality elevation and dip-strikes data extracted from outcrops or mining faces, is introduced in the form of physical constraints that control local changes in the estimated surface. Commonly accepted hypothesis states that geologic surfaces can be approximated to any desired degree of exactness by the summation of regular, mathematically defined, surfaces: in particular displaced quadric forms. The coefficients of the multiquadric functions are traditionally found by a least squares method. The addition of physical constraints in this work makes such an approach into a non-deterministic polynomial time problem. Hence we propose an objective function that represents the quality of the estimated surface and that includes the additional constraints by incorporation of a penalty function. Maximizing the smoothness of the estimated surface and its fitness to the additional constraints then allows the coefficients of the multiquadric function to be obtained by iterative methods. This method was implemented and demonstrated using data collected from the 81'st coal mining area of the Huaibei Coal Group. 展开更多
关键词 geologic surface spatial interpolation multiquadric function exterior penalty function physical constraints
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