Eigenvalue analyses of two parallel lines using a single real transformation matrix

For a typical non-symmetrical system with two parallel three phase transmission lines, modal transformation is applied using some examples of single real transformation matrices. These examples are applied searching an adequate single real transformation matrix to two parallel three phase transmission line systems. The analyses are started with the eigenvector and eigenvalue studies, using Clarke's transformation or linear combinations of Clarke's elements. The Z C and parameters are analyzed for the case that presents the smallest errors between the exact eigenvalues and the single real transformation matrix application results. The single real transformation determined for this case is based on Clarke's matrix and its main characteristic is the use of a unique homopolar reference. So, the homopolar mode becomes a connector mode between the two three-phase circuits of the analyzed system. ©2005 IEEE.

Jerim-320: A New 320-Bit Hash Function Compared To Hash Functions With Parallel Branches

This paper describes JERIM-320, a new 320-bit hash function used for ensuring message integrity and details a comparison with popular hash functions of similar design. JERIM-320 and FORK -256 operate on four parallel lines of message processing while RIPEMD-320 operates on two parallel lines. Popular hash functions like MD5 and SHA-1 use serial successive iteration for designing compression functions and hence are less secure. The parallel branches help JERIM-320 to achieve higher level of security using multiple iterations and processing on the message blocks. The focus of this work is to prove the ability of JERIM 320 in ensuring the integrity of messages to a higher degree to suit the fast growing internet applications

Analytical approximations to predict performance measures of manufacturing systems with job failures and parallel processing

Parallel processing is prevalent in many manufacturing and service systems. Many manufactured products are built and assembled from several components fabricated in parallel lines. An example of this manufacturing system configuration is observed at a manufacturing facility equipped to assemble and test web servers. Characteristics of a typical web server assembly line are: multiple products, job circulation, and paralleling processing. The primary objective of this research was to develop analytical approximations to predict performance measures of manufacturing systems with job failures and parallel processing. The analytical formulations extend previous queueing models used in assembly manufacturing systems in that they can handle serial and different configurations of paralleling processing with multiple product classes, and job circulation due to random part failures. In addition, appropriate correction terms via regression analysis were added to the approximations in order to minimize the gap in the error between the analytical approximation and the simulation models. Markovian and general type manufacturing systems, with multiple product classes, job circulation due to failures, and fork and join systems to model parallel processing were studied. In the Markovian and general case, the approximations without correction terms performed quite well for one and two product problem instances. However, it was observed that the flow time error increased as the number of products and net traffic intensity increased. Therefore, correction terms for single and fork-join stations were developed via regression analysis to deal with more than two products. The numerical comparisons showed that the approximations perform remarkably well when the corrections factors were used in the approximations. In general, the average flow time error was reduced from 38.19% to 5.59% in the Markovian case, and from 26.39% to 7.23% in the general case. All the equations stated in the analytical formulations were implemented as a set of Matlab scripts. By using this set, operations managers of web server assembly lines, manufacturing or other service systems with similar characteristics can estimate different system performance measures, and make judicious decisions - especially setting delivery due dates, capacity planning, and bottleneck mitigation, among others.

Analytical Approximations to Predict Performance Measures of Manufacturing Systems with Job Failures and Parallel Processing

Parallel processing is prevalent in many manufacturing and service systems. Many manufactured products are built and assembled from several components fabricated in parallel lines. An example of this manufacturing system configuration is observed at a manufacturing facility equipped to assemble and test web servers. Characteristics of a typical web server assembly line are: multiple products, job circulation, and paralleling processing. The primary objective of this research was to develop analytical approximations to predict performance measures of manufacturing systems with job failures and parallel processing. The analytical formulations extend previous queueing models used in assembly manufacturing systems in that they can handle serial and different configurations of paralleling processing with multiple product classes, and job circulation due to random part failures. In addition, appropriate correction terms via regression analysis were added to the approximations in order to minimize the gap in the error between the analytical approximation and the simulation models. Markovian and general type manufacturing systems, with multiple product classes, job circulation due to failures, and fork and join systems to model parallel processing were studied. In the Markovian and general case, the approximations without correction terms performed quite well for one and two product problem instances. However, it was observed that the flow time error increased as the number of products and net traffic intensity increased. Therefore, correction terms for single and fork-join stations were developed via regression analysis to deal with more than two products. The numerical comparisons showed that the approximations perform remarkably well when the corrections factors were used in the approximations. In general, the average flow time error was reduced from 38.19% to 5.59% in the Markovian case, and from 26.39% to 7.23% in the general case. All the equations stated in the analytical formulations were implemented as a set of Matlab scripts. By using this set, operations managers of web server assembly lines, manufacturing or other service systems with similar characteristics can estimate different system performance measures, and make judicious decisions - especially setting delivery due dates, capacity planning, and bottleneck mitigation, among others.

Tracking road edges in the panospheric image plane

This paper presents a technique for tracking road edges in a panoramic image sequence. The major contribution is that instead of unwarping the image to find parallel lines representing the road edges, we choose to warp the parallel groundplane lines into the image plane of the equiangular panospheric camera. Updating the parameters of the line thus involves searching a very small number of pixels in the panoramic image, requiring considerably less computation than unwarping. Results using real-world images, including shadows, intersections and curves, are presented.

Improving team dynamics and innovation : the “Aspect Design” approach applied to interaction design

Interaction Design is a fast developing branch of Industrial Design. The availability of cheap microprocessors and sensor electronics allow interactions between people and products that were until recently impossible. This has added additional layers of complexity to the design process. Novice designers find it difficult to effectively juggle these complexities and typically tend to focus on one aspect at a time. They also tend to take a linear, step-by-step approach to the design process in contrast to expert designers who pursue “parallel lines of thought” whilst simultaneously co-evolving both problem and solution. (Lawson, 1993) This paper explores an approach that encourages designers (in this case novice designers) to take a parallel rather than linear approach to the design process. It also addresses the problem of social loafing that tends to occur in team activities.

Alignment of nanoparticles formed on the surface of 6H-SiC crystals irradiated by two collinear femtosecond laser beams

Nanoripples with periods of 150 and 80 nm are formed on the surface of 6H-SiC crystals irradiated by the p-polarized 800 nm and the s-polarized 400 nm femtosecond lasers, respectively. When both of the two collinear laser beams focus simultaneously on the sample surface, nanoparticles are formed on the whole ablation area, and they array in parallel lines. We propose and confirm that the second harmonics in the sample surface excited by the incident lasers plays an important role in the formation of nanostructures.

A comunidade de pequenos mamíferos em áreas de savana metalófila e floresta ombrófila densa na Floresta Nacional de Carajás, PA: Estrutura, estratificação e impacto da mineração

Os pequenos mamíferos apresentam maior diversidade para a região Neotropical e são bons indicadores de alterações de habitats. Nós amostramos dois tipos de fitofisionomias. Os objetivos deste estudo foram avaliar a estrutura, a estratificação vertical e o impacto da mineração na comunidade de pequenos mamíferos nas áreas de Canga e Floresta. Foram amostradas seis linhas paralelas a partir da borda, em cada área. Foram instaladas 60 armadilhas intercaladas nos três estratos: solo, sub-bosque e dossel, durante seis noites consecutivas. E armadilhas de queda e interceptação, com 15 baldes em cada trilha, apenas nas áreas de Floresta. Foram amostradas uma área de cada fitofisionomia mais próxima e mais afastada do impacto, durante dois períodos chuvosos e dois secos, de 2009 a 2011. Nós encontramos diferenças muito evidentes quanto à composição e estrutura nos dois tipos de fitofisionomias amostradas: a riqueza foi maior na Floresta e a abundância total foi maior na Canga. Das 24 espécies amostradas, 15 foram registradas exclusivamente no solo, oito no solo e sub-bosque e uma (Glironia venusta) exclusivamente no dossel. Apenas Micoureus demerarae foi registrado nos três estratos e Caluromys philander apenas no sub-bosque e dossel. O efeito do impacto é muito evidente nas Florestas e menos nas Cangas. Nas Florestas, quanto mais distante do impacto, maior a riqueza e abundância de espécies. É importante a continuidade e o aprofundamento de estudos com comunidades de pequenos mamíferos na Floresta Nacional de Carajás, ampliando o conhecimento científico para propor medidas que minimizem o impacto causado pela atividade mineradora na região.

An integrated model of rolling tyre vibrations on a smooth road

We describe new results on the vibrations of rolling tyres, aimed at noise prediction for tyres of given design on a smooth road surface. This new approach incorporates our existing models, of smooth road-tyre interaction and belt vibration but includes additional features that are required for real tyre patterns. To this end, the model allows variable tread block size and grooves along the belt circumference; the density and angle of these grooves may also vary laterally. The key innovation is to treat the tyre belt as a laterally stacked series of rings, each of which is equipped with a set of viscoelastic springs around its circumference. It is shown how to use this construction to mimic the details of actual tyre patterns and, in conjunction with existing models, predict belt vibrations. The construction is applied to develop a ring discretisation for a real tyre that shows strong lateral variations. It is shown that the vibration amplitude is concentrated on a set of parallel lines in frequency-wavenumber space and that the tread pattern dictates the occurrence and spacing of these lines. Linkage to a boundary element calculation then allows quantification of the influence of tread parameters on radiated noise. Keywords: Vibration, tread pattern, tyre noise. Copyright © (2011) by the Institute of Noise Control Engineering.

Heteroepitaxial Growth of 3C-SiC Films on Maskless Patterned Silicon Substrates

Heteroepitaxial growth of 3C-SiC on patterned Si substrates by low pressure chemical vapor deposition (LPCVD) has been investigated to improve the crystal quality of 3C-SiC films. Si substrates were patterned with parallel lines, 1 to 10μm wide and spaced 1 to 10μm apart, which was carried out by photolithography and reactive ion etching. Growth behavior on the patterned substrates was systematically studied by scanning electron microscopy (SEM). An air gap structure and a spherical shape were formed on the patterned Si substrates with different dimensions. The air gap formed after coalescence reduced the stress in the 3C-SiC films, solving the wafer warp and making it possible to grow thicker films. XRD patterns indicated that the films grown on the maskless patterned Si substrates were mainly composed of crystal planes with (111) orientation.

Parallels plane projection and its geometric features

A new equivalent map projection called the parallels plane projection is proposed in this paper. The transverse axis of the parallels plane projection is the expansion of the equator and its vertical axis equals half the length of the central meridian. On the parallels plane projection, meridians are projected as sine curves and parallels are a series of straight, parallel lines. No distortion of length occurs along the central meridian or on any parallels of this projection. Angular distortion and the proportion of length along meridians (except the central meridian) introduced by the projection transformation increase with increasing longitude and latitude. A potential application of the parallels plane projection is that it can provide an efficient projection transformation for global discrete grid systems.

小学儿童空间物体位置编码的实验研究

As a key issue in spatial cognitive developmental research, the coding of object location plays an important role in children's cognitive development. The development of location coding is a precondition for children's adaptation to their environments, and the development of corresponding ability could enhance children's adaptation ability and improve their synthetic diathesis. In this paper, under the improved paradigm of object searching, 7-, 9- and 11-year-olds of urban primary school students were involved in two studies including the total of four experiments. The children were examined upon the ability to encode target location in terms of the distance between two landmarks, three points on a line, the intersection of two lines, or the corresponding points on two parallel lines. The experiments were designed to explore the primary school children's cognitive developmental process upon spatial object location and the correlative restricting factors. From the studies, the following conclusions were drawn: 1)The ability of 7-year-olds to represent target location in terms of the relationships of points and lines is in the inceptive stage and appears unstable. Meanwhile, the same ability of 9-year-olds is in a state of fast developing. The 9-year-olds' performance depends on how difficult the task is. It is stable when task is easy while unstable when task becomes difficult. The ability of 11-year-olds reaches much-developed state and the group's performance is independent of the difficulty of tasks. 2) The correlate coefficient is significant between Raven Standard Inference ability levels and the performance of representing target location in terms of the relationships of points. Those children with good performance in Raven Standard Inference Test have good performance in target location coding. The case is true for all different age groups. As of the task in terms of the relationships of lines, the correlate coefficient between Raven Standard Inference ability levels and children's performance of representing target location is found significant only for the 7-year-olds' group. The case is not true for the groups of 9- and 11-year-olds. It is also found that the correlate coefficient is significant between the sum of performance and Raven Standard Inference ability levels, and that is true for all age groups. 3) Effects from task variable exist upon children's above-mentioned cognitive performance. The effects are different according to different difficulty levels of tasks. Also, they are different according to the different ages. 4) The subjects who failed in the 'no cues for encoding given' situation were able to improve their performances when the cues of encoding were given. Therefore it is possible to improve the primary school children's corresponding cognitive performance by providing the cues of encoding. 5) Two kinds of efficient strategies were used to solve the problem. They are trial-comparison strategy and anticipation-directed strategy.

The Role of Edges and Line-Ends in Illusory Contour Formation

Illusory contours can be induced along directions approximately collinear to edges or approximately perpendicular to the ends of lines. Using a rating scale procedure we explored the relation between the two types of inducers by systematically varying the thickness of inducing elements to result; in varying amounts of "edge-like" or "line-like" induction. Inducers for om illusory figures consisted of concentric rings with arcs missing. Observers judged the clarity and brightness of illusory figures as the number of arcs, their thicknesses, and spacings were parametrically varied. Degree of clarity and amount of induced brightness were both found to be inverted-U functions of the number of arcs. These results mandate that any valid model of illusory contour formation must account for interference effects between parallel lines or between those neural units responsible for completion of boundary signals in directions perpendicular to the ends of thin lines. Line width was found to have an effect on both clarity and brightness, a finding inconsistent with those models which employ only completion perpendicular to inducer orientation.

The Role of Edges and Line-Ends in Illusory Contour Formation

Illusory contours can be induced along direction approximately collinear to edges or approximately perpendicular to the ends of lines. Using a rating scale procedure we explored the relation between the two types of inducers by systematically varying the thickness of inducing elements to result in varying amounts of "edge-like" or "line-like" induction. Inducers for our illusory figures consisted of concentric rings with arcs missing. Observers judged the clarity and brightness of illusory figures as the number of arcs, their thicknesses, and spacings were parametrically varied. Degree of clarity and amount of induced brightness were both found to be inverted-U functions of the number of arcs. These results mandate that any valid model of illusory contour formation must account for interference effects between parallel lines or between those neural units responsible for completion of boundary signals in directions perpendicular to the ends of thin lines. Line width was found to have an efFect on both clarity and brightness, a finding inconsistent with those models which employ only completion perpendicular to inducer orientation.