A two-parameter multiple shooting method and its application to the natural vibrations of non-prismatic multi-segment beams

This paper presents an enhanced version of the standard shooting method that enables problems with two unknown parameters to be solved.A novel approach is applied to the analysis of the natural vibrations of Euler-Bernoulli beams.The proposed algorithm,named as two-parameter multiple shooting method,is a new powerful numerical tool for calculating the natural frequencies and modes of multi-segment prismatic and non-prismatic beams with different boundary conditions.The impact of the axial force and additional point masses is also taken into account.Due to the fact that the method is based directly on the fourth-order ordinary differential equation,the structures do not have to be divided into many small elements to obtain an accurate enough solution,even though the geometry is very complex.To verify the proposed method,three different examples are considered,i.e.,a three-segment non-prismatic beam,a prismatic column subject to non-uniformly distributed compressive loads,and a two-segment beam with an additional point mass.Numerical analyses are carried out with the software MATHEMATICA.The results are compared with the solutions computed by the commercial finite element program SOFiSTiK.Good agreement is achieved,which confirms the correctness and high effectiveness of the formulated algorithm.

Efficient Decomposition Shooting Method for Solving Third-Order Boundary Value Problems

The present paper proposes a mathematical method to numerically treat a class of third-order linear Boundary Value Problems (BVPs). This method is based on the combination of the Adomian Decomposition Method (ADM) and, the modified shooting method. A complete derivation of the proposed method has been provided, in addition to its numerical implementation and, validation via the utilization of the Runge-Kutta method and, other existing methods. The method has been applied to diverse test problems and turned out to perform remarkably. Lastly, the simulated numerical results have been graphically illustrated and, also supported by some absolute error comparison tables.

Influence of core box vents distribution on flow dynamics of core shooting process based on experiment and numerical simulation

Core shooting process plays a decisive role in the quality of sand cores, and core box vents distribution is one of the most important factor determining the effectiveness of core shooting process. In this paper, the influence of core box vents distribution on the flow dynamics of core shooting process was investigated based on in situ experimental observations with transparent core box, high-speed camera and pressure measuring system. Attention was focused on the variation of both the flow behavior of sand and pressure curves due to different vents distribution. Taking both kinetic and frictional stress into account, a kinetic-frictional constitutive model was established to describe the internal momentum transfer in the solid phase. Two-fluid model(TFM) simulation was then performed and good agreement was achieved between the experimental and simulated results on both the flow behavior of sand and the pressure curves. It was found that vents distribution has direct effect on the pressure difference of different locations in the core box, which determines the buoyancy force exerting on the sand particles and significantly influences the filling process of core sand.

A CASE STUDY ON LONG HOLE RAISING BY SHOOTING TO RELIEF HOLES

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Optimal index shooting policy for layered missile defense system

In order to cope with the increasing threat of the ballistic missile(BM)in a shorter reaction time,the shooting policy of the layered defense system needs to be optimized.The main decisionmaking problem of shooting optimization is how to choose the next BM which needs to be shot according to the previous engagements and results,thus maximizing the expected return of BMs killed or minimizing the cost of BMs penetration.Motivated by this,this study aims to determine an optimal shooting policy for a two-layer missile defense(TLMD)system.This paper considers a scenario in which the TLMD system wishes to shoot at a collection of BMs one at a time,and to maximize the return obtained from BMs killed before the system demise.To provide a policy analysis tool,this paper develops a general model for shooting decision-making,the shooting engagements can be described as a discounted reward Markov decision process.The index shooting policy is a strategy that can effectively balance the shooting returns and the risk that the defense mission fails,and the goal is to maximize the return obtained from BMs killed before the system demise.The numerical results show that the index policy is better than a range of competitors,especially the mean returns and the mean killing BM number.

Influence of core sand properties on flow dynamics of core shooting process based on experiment and multiphase simulation

The influence of core sand properties on flow dynamics was investigated synchronously with various core sands, transparent core-box and high-speed camera. To confirm whether the core shooting process has significant turbulence, the flow pattern of sand particles in the shooting head and core box was reproduced with colored core sands. By incorporating the kinetic theory of granular flow(KTGF), kinetic-frictional constitutive correlation and turbulence model, a two-fluid model(TFM) was established to study the flow dynamics of the core shooting process. Two-fluid model(TFM) simulations were then performed and a areasonable agreement was achieved between the simulation and experimental results. Based on the experimental and simulation results, the effects of turbulence, sand density, sand diameter and binder ratio were analyzed in terms of filling process, sand volume fraction(αs) and sand velocity(Vs).

The Lie-group Shooting Method for Radial Symmetric Solutions of the Yamabe Equation

We transform the Yamabe equation on a ball of arbitrary dimension greater than two into a nonlinear singularly boundary value problem on the unit interval[0;1].Then we apply Lie-group shooting method(LGSM)to search a missing initial condition of slope through a weighting factor r 2(0;1).The best r is determined by matching the right-end boundary condition.When the initial slope is available we can apply the group preserving scheme(GPS)to calculate the solution,which is highly accurate.By LGSM we obtain precise radial symmetric solutions of the Yamabe equation.These results are useful in demonstrating the utility of Lie-group based numerical approaches to solving nonlinear differential equations.

A SHOOTING METHOD FOR THE SWIFT-HOHENBERG EQUATION

Stationary even single bump periodic solutions of the Swift Hohenberg equation are analyzed. The coefficient k in the equation is found to be a critical parameter. It is proved if 0<k<1 , there exist periodic solutions having the same energy as the constant solution u=0; if 1<k<32 , there exist periodic solutions having the same energy as the stable states u=±k-1. The proof of the above results is based on a shooting technique, together with a linearization method and a scaling argument.

Analysis on Stochastic Passage Characteristics for Gun Barrel in Shooting Domain

Aiming at some weapon systems with shooting domain,the stochastic passage characteristics of the barrel were studied.On the basis of the exact definition of the stochastic passage characteristics,its opportunity-awaiting time,residence time and stochastic passage period were given by using the transition probability matrix,and they all obeyed the geometry distributions.Their means and variances were also derived,and the relations between the time indexes and the structure and parameters of weapon control system were established.Finally,the creditability of the conclusions was verified by the test data of weapon system in proving ground.

GPU based numerical simulation of core shooting process

Core shooting process is the most widely used technique to make sand cores and it plays an important role in the quality of sand cores. Although numerical simulation can hopefully optimize the core shooting process, research on numerical simulation of the core shooting process is very limited. Based on a two-fluid model(TFM) and a kinetic-friction constitutive correlation, a program for 3D numerical simulation of the core shooting process has been developed and achieved good agreements with in-situ experiments. To match the needs of engineering applications, a graphics processing unit(GPU) has also been used to improve the calculation efficiency. The parallel algorithm based on the Compute Unified Device Architecture(CUDA) platform can significantly decrease computing time by multi-threaded GPU. In this work, the program accelerated by CUDA parallelization method was developed and the accuracy of the calculations was ensured by comparing with in-situ experimental results photographed by a high-speed camera. The design and optimization of the parallel algorithm were discussed. The simulation result of a sand core test-piece indicated the improvement of the calculation efficiency by GPU. The developed program has also been validated by in-situ experiments with a transparent core-box, a high-speed camera, and a pressure measuring system. The computing time of the parallel program was reduced by nearly 95% while the simulation result was still quite consistent with experimental data. The GPU parallelization method can successfully solve the problem of low computational efficiency of the 3D sand shooting simulation program, and thus the developed GPU program is appropriate for engineering applications.

Scattering from Rough Surfaces Using the"Shooting and Bouncing Rays" Technique

The “shooting and bouncing rays” (SBR) technique is used to analyze the electromagnetic scattering characters of ocean rough surfaces varying with time. Some numerical results are presented and compared with the method of moments, and some factors, such as the incident angle, polarization and frequency are investigated which influence on electromagnetic scattering characters of ocean rough surfaces.

Supremacy of Social Media in the Hebron Shooting Incident

The controversy in the case of Elor Azaria,an Israeli soldier who shot a Palestinian assailant in the Palestinian city of Hebron,after he was wounded and neutralized,led to a highly emotional public debate threatening a major crisis in the government and society.The incident divided the Israeli public and its leaders,with some expressing outrage over the killing of an incapacitated man,and others supporting even the most extreme response to a stabbing attack.The research argues that the role of governments in preventing exposure of security information was badly shaken following the inability to control information,as the incident was recorded on a mobile phone and uploaded to social media.As demonstrated in this case,local organizations have assumed a new prominence by providing information that previously had been limited by local authorities.The research is looking at the question of who was superior in the Hebron shooting incident:the army,the government,public opinion,traditional media or social media.The conclusions in this case are clear-cut:Social media dominated the entire process and determined its outcome,which was obvious once the video was uploaded on the Internet.

Reliability and Validity of the New Shooting Accuracy Measurement （SAM） System Software

The aim of this study was to investigate the reliability and validity of the New Shooting Accuracy Measurement Software （SAMS）. Thirty two male collegian soccer players performed three inner side kicking to the transparent goal construction. A High speed camera was placed at the back of the construction to determine where the ball contacted. Recorded video results were assessed with the SAMS and Kinovea software. To investigate test-retest reliability, three kicking results were examined twice by SAMS. Moreover kicking accuracy results obtained with SAMS were compared with results provided by Kinovea in order to investigate validity. Test-retest reproducibility of the new software was excellent, with Concordance Correlation Coefficient for distance to target （0.99, 0.99 and 0.99 respectively） and for angular degree of the ball （0.97, 0.99 and 0.99 respectively）, low Coefficients of Variation （between 2.10 to 6.33 for distance to target and 2.40 to 2.69 for angular degree） and random error （between _.＋ 0.55 to __＋ 3.44 for distance to target and ___ 0.63 to ___ 2.75 for angular degree）. Constant error （between 0.44 to 1.28 for distance to target and -1.16 to __. -2.51 for angular degree） and proportional error （between 0.97 to 0.98 for distance to target and 1.00 to 1.01 for angular degree） were very low for validity. In conclusion, the SAMS represents a valid and reliable instrument to measure accuracy of shooting to target.

Shooting for Immortality

Some people kill others as well as themselves in the hope of achieving fame. Even more, some people seek spectacular displays of carnage. This danger is the focus of my essay. I argue that the pursuit of fame is able to generate mass killings because of a hope for personal immortality underlying the pursuit. Primarily through the work of Miguel de Unamuno and Ernest Becker, I argue that the hope for immortality is a powerful yet amoral impulse that is able to generate a lethal pursuit of fame. I argue that linking fame to one＇s social immortalization exacerbates the conflict already present in the pursuit of fame as well as enables the fame seeker to reduce all others to a means. Following my theoretical analysis, I turn to the iconic shootings at Columbine High School. The shootings offer a practical exemplification of how the pursuit of social immortalization can generate mass carnage. I argue that understanding the tragedy of Columbine as predicated upon a hope for social immortalization offers a template for destruction that ought to be considered when examining other, and all too frequent, instances of mass violence.

Trouble Shooting and Debugging Skills of Rectification and Capacitance Components of Doppler Weather Radar

Based on the CINRAD/SA user manual and the American WSR-88D technical guide,the working principle,parameters,debugging preparation,debugging process and debugging methods of rectification and capacitance components of Doppler radar were analyzed in detail,and the main trouble reasons were also introduced.

Shooting Back

A project that puts cameras in the hands of war’s youngest victims offers them away to tell—and show——their stories. Two million children dead.Six millionmaimed or mutilated.Ten million psychologicallydamaged.Such is the tragic tally,in the last decade,of the world’s wars.border skirmishes and ethnicconflicts.And it doesn’t stop there.According toa 1999 report by the U.N.’s Special Representativefor Children and Armed Conflict,more than

Distribution of Soil-Bound Lead Arising from Rainfall-Runoff Events at Impact Berm of a Military Shooting Range

Surface runoff from rainfall event is an important indicator of metal mobility in soil, which may enhance non-point source contamination of soil. This study is designed to assess the mobility of soil-bound lead through simulated rainfall runoff experiment and its spatial distribution within the vicinity of a berm at a major military shooting range. Contamination was more significant at the impact area of berm, indicating threefold increase in Pb (17,500 ± 3811 μg/g) within a space of ten years. However, the non-impact area (459 ± 147 μg/g) was less contaminated. Other metals (Cu, Cd, Cr, Ni and Zn) analyzed were about background levels except for Cu at impact area. The enrichment ratio of Pb in runoff sediments was mostly high for the 0.43 mm sediment fractions independent of rainfall condition. Principal component analysis (PCA) biplot showed strong correlation between spatial distributions of metals around the vicinity of the berm (farmlands behind the berm) with concentrations on the impact berm soil. Surface runoff simulated on impact area soil had high concentrations of Pb (40.4 - 65.6 μg/mL) which could further lead to enrichment of soil-Pb levels within the vicinity of the berm. Decontamination measure is therefore required to minimize extensive contamination of surrounding soils of the impact berm due to rainfall runoff events.

Research on the Best Shooting State Based on the “Three Forces” Model

The shooting state during shooting refers to the basketball’s shooting speed,shooting angle and the ball’s rotation speed.The basketball flight path is also related to these factors.In this paper,based on the three forces of Gravity,Air Resistance and Magnus Force,the“Three Forces”model is established,the Kinetic equations are derived,the basketball flight trajectory is solved by simulation,and the best shot state when shooting is obtained through the shooting percentage.Compared with the“Single Force”model that only considers Gravity,the shooting percentage of the“Three Forces”model is higher.The reason is that the Magnus Force generated by considering the basketball rotation speed is considered.Although in the“Three Forces”model,the shot speed is faster and the shot is harder,the backspin will reduce the angle of the shot and achieve the goal of saving effort.By calculating the best shot state and giving the athlete’s usual training state range,you can guide the training,thereby improving the athlete’s shooting percentage during the game.

The Effect of Functional Training on the Performance of Female Handball Players’Shooting Skills

A randomized grouping experiment was conducted to study the effect of 8-week functional training on shooting performance of Beijing female handball players.According to the athletes’FMS(functional movement screening)scoring results,they were randomly divided into 2 groups.The experimental group adopted an 8-week functional training,aiming at strengthening their core strength,joint stability,and the power chain of shooting techniques.The control group adopted the traditional strength training mode.ANOVA(analysis of variance)was adopted to analyze the different performance of the athletes from two groups on their FMS scores,distances of throwing,and 7-meter shooting speed before and after the experiment.The results show that:(1)the total FMS scores of the experimental group athletes have been increased more significantly than those of the control group,and the injuries per capita has been significantly reduced;(2)the athletes in the experimental group have more significantly improved performance in handball throwing and 7-meter shooting speed than those in the control group.It shows that 8 weeks of functional training may effectively improve the physical function of Beijing female handball players and their performance in two special skills of handball throwing and shooting speed.

Single-handed Shooting Action in Basketball Teaching Techniques Biomechanical Analysis

Basketball shooting technique is the core technology. The shooting angle, basket entering angle, ball＇s rotation, aiming at point, exerting strength cooperatively with the whole body, and flicking the ball using index finger before it leaves from hand are the important factors to decide if the shooting techniques are reasonable and the successful shooting rate is high or not. In this paper, the theory of biomechanics is analyzed around basketball spin on the role of shooting, shooting aiming point selection diversity, difference and its impact on investment and basketball shooting rate.