Conditional Poisson Stochastic Beams

Beam search is the default decoding strategy for many sequence generation tasks in NLP. The set of approximate K-best items returned by the algorithm is a useful summary of the distribution for many applications; however, the candidates typically exhibit high overlap and may give a highly biased estimate for expectations under our model. These problems can be addressed by instead using stochastic decoding strategies. In this work, we propose a new method for turning beam search into a stochastic process: Conditional Poisson stochastic beam search. Rather than taking the maximizing set at each iteration, we sample K candidates without replacement according to the conditional Poisson sampling design. We view this as a more natural alternative to Kool et al. (2019)'s stochastic beam search (SBS). Furthermore, we show how samples generated under the CPSBS design can be used to build consistent estimators and sample diverse sets from sequence models. In our experiments, we observe CPSBS produces lower variance and more efficient estimators than SBS, even showing improvements in high entropy settings.

Study of the characteristics of the 6MV photon package from Varian IX linear medical accelerator using BEAMnrc code

The codes (EGSnrc, BEAMnrc) are used to simulate 6MV photon beam produced by Varian ix linear accelerator and different field size (2020, 1010, 44cm2). The simulation data is stored in a phase space file that contains complete details of the dates of each particle by tracking its path and interactions. Phase space files were analyzed using BEAMDP code to: - Obtain energy spectrum, energy flow, distribution of the mean energy and the angular distribution of the photons and contaminant electrons on surface of water phantom and 100cm away from linear accelerator head. - Study effect of field size on distribution of the energy spectrum 6MV. - Study of change in distribution of mean energy between center and edge of the field size. - Calculation the contribution of contaminant electrons within photonic beam at 21%.

Evaluation of the Upper Airway Changes in Class II Patients Resulting From Functional Treatment Using Cone Beam Computed Tomography - An In Vivo Study

Objective: This research aimed to evaluate the three-dimensional effects of a Twin Block (TB) appliance on the pharyngeal airway passage (PAP) in a sample of Class II patients with mandibular retrusion using cone-beam computed tomography (CBCT).

The Effect of Rapid Maxillary Expansion on the Spheno-occipital Synchondrosis in Children using Cone Beam Computed Tomography

The RME force is not only concentrated on widening the maxilla, it is concomitant changes occur in craniofacial sutures, from here the need for this study was originated. Aim of the study: To investigate the immediate effect of rapid maxillary expansion on the spheno-occipital Synchondrosis in children using cone beam computed tomography.

Study and characterization of acoustic gain of parabolic reflector

The parabolic reflector is used in directed acoustic systems, with the aim of gettingdirectivity, as well as increasing the gain in transmission and reception. Therefore, a theoretical study was carried out to describe the factors that affect the gain of the parabolic dish in the acoustic field. The frequency-gain relationship was experimentally obtained using a parabolic dish with an elliptical aperture, in addition to the analysis of the factors that led to the deviation of the experimental relationship from the theoretical relationship.

Computer Assisted FEA of the Hollow Rectangular Telescopic Cantilever Beam Buckling

The telescopic cantilever beam is widely used in different types of cranes. These structures are flexible; it can expand or shrink according to the operating conditions. The dynamic changes of the total length of the structure lead to time-dependent vibrational characteristics. In practice, CAD modeling for this case is a challenging matter due to the nature of the problem of analyzing stress and deformation occurring during the operation of the crane. This research discusses the feasibility of finding a solution for the design problems initialized during the failure of the telescopic cantilever beam through the application of Finite Element Analyses (FEA) in order to find the ideal dimension of the structure which represents the best design for the telescopic cantilever beam.

Realistic models of the forms of deformation and collapse in concrete road bridges caused by blast load

Blast load caused emptying a large amount of energy very quickly parts of the second causing a significant increase of pressure, in addition to generating high temperatures because of the high speed often ends local effects of the explosion before the bridge begins to respond, which causing major damage in the bridge. Most of bridge design codes didn’t take in account during design the blast load, as well there are no codes inspection on bridges the blast load. The research aims to study and to facilitate the understanding of damages caused by explosion load on elements of road bridges through the facts of explosion and photographs the cases of damages occurring practical and realistic, and also through some computer models.It has been in the research review the impact of the blast load on the slab bridges. The distinction between the case of the impact of the blast load at top and bottom of slab bridge. So the case of the bombing at the top slab bridge leading to increase the binding moments and shear forces, in against the case of blasting at the bottom of slab bridges leads to act opposite load for design loads. Also studied blast load on bridge beams and illustrated resulting addional cross sections. Also explained the effect of blast load on bridge piers and abutments, and the forms of caused damages.

Analytical study of the behavior of R.C beam-column joint under cyclic load using ANSYS program

This research deals with analytical study of exterior Beam-Column connections behavior under seismic load. Tow parameters were considered: axial load on the column and confinement of joint region with stirrups. Ansys program was used to analytical study of three types of exterior Beam-Column connections under cyclic load. The results were shown a good agreement with general behavior of three types. The analytical results indicate that the tow parameters will improve the behavior of the connections delay cracking at joint core and increasing connection stiffness in rotation and displacement with decreasing shear value at joint.

A Study of maxillary and mandibular alveolar widths in skeletal class II compared with skeletal class I in adults ) Cone-Beam Computed Tomography Study )

Class II malocclusion is a common clinical problem among white Caucasian population and its transverse component is a critical aspect of a functional and stable occlusion. The size and shape of the arches have considerable implications in orthodontic diagnosis and treatment planning, affecting the space available, dental esthetics, and stability of the dentition. Hence , it is important to study the alveolar arch width in this group of patients using the wide possibilities of cone beam computed tomography of evaluating real anatomy , true-to-scale images without distortions or superimpositions, and the selection of the desired sections.Objective:To evaluate the width of maxillary and mandibular alveolar arches in skelatal Class II adults compared to skeletal class I using cone beam computed tomography. Materials and methods: thirty-two subjects with skeletal Class II relationship and 10 subjects with skeletal Class I who were ordinary undergoing CBCT scan for non-orthodontics nor for otorihnolaryngology purpose were selected to measure the maxillary and mandibular alveolar width of first premolar and first molars.Independent samples’ t-test was calculated. Results:No statistically significant differences were found of alveolar widths between skeletal Class II and Class I subjects in both maxillary and mandibular widths of molar and premolar regions. Gender had no statistically significant effect in the results of the study. Conclusion :There is no differences in alveolar width between adults with skeletal Class II and Class I relationships, so the transverse discrepancy in skeletal Class II when exsists , it is more probably not originated from the alveolar base.

Thermal – Structural Behavior of Steel Beam Under Influence of Temperature

Stability of elements require determination of their dimension, such that the resulting displacement under static or thermal loads are acceptable. Those elements have to resist the applied loads so that the structure or any element does not loss constancy. The most important criteria for stability is represented via element curvature under the influence of load, that load is of any type or in any position. Therefor this paper presents derivation of a theoretical equation to calculate the deflection generated from heating variation between the top and bottom surface of simple steel beam, by means of heating transfer expression.