다중혈관 관상동맥 환자에서 y-문합을 이용하여 양쪽 내흉동맥만을 사용한 우회술의 조기 성적

Deposits of clastic carbonate-dominated (calciclastic) sedimentary slope systems in the rock record have been identified mostly as linearly-consistent carbonate apron deposits, even though most ancient clastic carbonate slope deposits fit the submarine fan systems better. Calciclastic submarine fans are consequently rarely described and are poorly understood. Subsequently, very little is known especially in mud-dominated calciclastic submarine fan systems. Presented in this study are a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) that reveals a >250 m thick calciturbidite complex deposited in a calciclastic submarine fan setting. Seven facies are recognised from core and thin section characterisation and are grouped into three carbonate turbidite sequences. They include: 1) Calciturbidites, comprising mostly of highto low-density, wavy-laminated bioclast-rich facies; 2) low-density densite mudstones which are characterised by planar laminated and unlaminated muddominated facies; and 3) Calcidebrites which are muddy or hyper-concentrated debrisflow deposits occurring as poorly-sorted, chaotic, mud-supported floatstones. These

Phd by thesis

Fractional Differential Equations

Thank you for reading principles of optics electromagnetic theory of propagation interference and diffraction of light. As you may know, people have search hundreds times for their favorite novels like this principles of optics electromagnetic theory of propagation interference and diffraction of light, but end up in harmful downloads. Rather than enjoying a good book with a cup of coffee in the afternoon, instead they are facing with some infectious bugs inside their computer.

Principles Of Optics Electromagnetic Theory Of Propagation Interference And Diffraction Of Light

Much has been written about theory and practice in the law, and the tension between practitioners and theorists. Judges do not cite theoretical articles often; they rarely "apply" theories to particular cases. These arguments are not revisited. Instead the Essay explores the working and interaction of theory and practice, practitioners and theorists. The Essay starts with a story about solving a legal issue using our intellectual tools - theory, practice, and their progenies: experience and "gut." Next the Essay elaborates on the nature of theory, practice, experience and "gut." The third part of the Essay discusses theories that are helpful to practitioners and those that are less helpful. The Essay concludes that practitioners theorize, and theorists practice. They use these intellectual tools differently because the goals and orientations of theorists and practitioners, and the constraints under which they act, differ. Theory, practice, experience and "gut" help us think, remember, decide and create. They complement each other like the two sides of the same coin: distinct but inseparable.

Of Theory and Practice

Rapidly Exploring Random Tree (RRT) is one of the quickest and the most efficient obstacle free path finding algorithm. However, it cannot guarantee finding the most optimal path. A recently proposed extension of RRT, known as Rapidly Exploring Random Tree Star (RRT∗), claims to achieve convergence towards the optimal solution but has been proven to take an infinite time to do so and with a slow convergence rate. To overcome these limitations, we propose an extension of RRT∗, called RRT∗-Smart, which aims to accelerate its rate of convergence and to reach an optimum or near optimum solution at a much faster rate and at a reduced execution time. Our novel algorithm inculcates two new techniques in RRT∗: these are path optimization and intelligent sampling. Simulation results presented in various obstacle cluttered environments confirm the efficiency of RRT∗-Smart.

RRT ∗ -Smart: Rapid convergence implementation of RRT ∗ towards optimal solution

Many sampling based algorithms have been introduced recently. Among them Rapidly Exploring Random Tree (RRT) is one of the quickest and the most efficient obstacle free path finding algorithm. Although it ensures probabilistic completeness, it cannot guarantee finding the most optimal path. Rapidly Exploring Random Tree Star (RRT*), a recently proposed extension of RRT, claims to achieve convergence towards the optimal solution thus ensuring asymptotic optimality along with probabilistic completeness. However, it has been proven to take an infinite time to do so and with a slow convergence rate. In this paper an extension of RRT*, called as RRT*-Smart, has been prposed to overcome the limitaions of RRT*. The goal of the proposecd method is to accelerate the rate of convergence, in order to reach an optimum or near optimum solution at a much faster rate, thus reducing the execution time. The novel approach of the proposed algorithm makes use of two new techniques in RRT*-- Path Optimization and Intelligent Sampling. Simulation results presented in various obstacle cluttered environments along with statistical and mathematical analysis confirm the efficiency of the proposed RRT*- Smart algorithm.

/pdf/rrt-smart-a-rapid-convergence-implementation-of-rrt-xk6928pf6s.pdf

RRT*-SMART: A Rapid Convergence Implementation of RRT*

Reliability modeling and analysis of communication networks

Approximate adders are widely being advocated as a means to achieve performance gain in error resilient applications. In this paper, a generic methodology for analytical modeling of probability of occurrence of error and the Probability Mass Function (PMF) of error value in a selected class of approximate adders is presented, which can serve as performance metrics for the comparative analysis of various adders and their configurations. The proposed model is applicable to approximate adders that comprise of sub-adder units of uniform as well as non-uniform lengths. Using a systematic methodology, we derive closed form expressions for the probability of error for a number of state-of-the-art high-performance approximate adders. The probabilistic analysis is carried out for arbitrary input distributions. It can be used to study the dependence of error statistics in an adder’s output on its configuration and input distribution. Moreover, it is shown that by building upon the proposed error model, we can estimate the probability of error in circuits with multiple approximate adders. We also demonstrate that, using the proposed analysis, the comparative performance of different approximate adders can be correctly predicted in practical applications of image processing.

Probabilistic Error Modeling for Approximate Adders

On June 1, 2009, Air France Flight 447 from Rio de Janeiro to Paris crashed into the Atlantic Ocean, killing all 216 passengers and 12 crew members. Prior to the disappearance of the A330 aircraft, the automatic reporting system sent messages indicating disagreement in the airspeed readings, which led investigators to believe that the pilot probe sensors did not “accurately” measure airspeed and the autopilot may have automatically disengaged. Like the above probes, many systems are increasingly being used in safety-critical domains, such as medicine, transportation systems, chemical plants, etc. There is hence a dire need to ensure the accuracy of such systems as a system bug, or error, may endanger human life or lead to a significant financial loss. In order to ensure error-free systems, the system design process is usually accompanied by a rigorous system analysis to check if the designed system would exhibit the desired behavior. The core of system analysis is based on mathematics and the fundamental idea is to create a mathematical model of the system and then use logical or mathematical reasoning to verify that the desired properties hold for this model. Traditionally, system analysis is done by paper-and-pencil proof methods. However, considering the complexity of present age systems, such kind of analysis is notoriously difficult, if not impossible, and is quite error prone due to the human error factor. Moreover, it is quite often the case that mathematicians forget to pen down all the assumptions that are required for the validity of their analysis. This fact may also result in designing erroneous systems. With the advent of computers, many computer based software tools based on the principle of testing or simulation have been introduced for system verification. Due to the reliable and efficient bookkeeping characteristic of computers, large systems can be analyzed and thus one of the limitations of paper-and-pencil proof methods can be overcome. However, the main problem with such kind of analysis is its completeness as the system is checked only for a subset of possible inputs since exhaustive testing is not possible for any system with a significant number of inputs due to the exponential growth of the test patterns. In Dijkstra’s words “Program testing can be a very effective way to show the presence of bugs, but it is hopelessly inadequate for showing their absence.” Moreover, testing or simulation cannot be used to precisely verify properties about continuous systems due to the usage of computer arithmetic, like floating-point or fixed-point representations of real numbers. The above mentioned inaccuracy limitations of commonly used system analysis techniques can be held responsible for many unfortunate incidents that happened due to an erroneous system deployed in a safety-critical domain For example, the Therac-25 software bug and the Intel Pentium’s floating-point division unit error).

Osman Hasan

Papers

RRT ∗ -Smart: Rapid convergence implementation of RRT ∗ towards optimal solution

RRT-SMART: A Rapid Convergence Implementation of RRT

Reliability modeling and analysis of communication networks

Probabilistic Error Modeling for Approximate Adders

Formal Verification Methods