Comparing multimedia storage architectures

Multimedia interfaces increase the need for large image databases, capable of storing and reading streams of data with strict synchronicity and isochronicity requirements. In order to fulfil these requirements, we use a parallel image server architecture which relies on arrays of intelligent disk nodes, each disk node being composed of one processor and one or more disks. This contribution analyzes through simulation the real-time behavior of two multiprocessor multi-disk architectures: GigaView and the Unix workstation cluster. GigaView incorporates point-to-point communication between processing units and the workstation cluster supports communication through a shared bus-and-memory architecture. For a standard multimedia server architecture consisting of 8 disks and 4 disk-node processors, we evaluate stream frame access times under various parameters such as load factors, frame size, stream throughput and synchronicity requirements. We compare the behavior of GigaView and the workstation cluster in terms of delay and delay jitte

Multimedia performance behavior of the GigaView parallel image server

Multimedia interfaces increase the need for large image databases, supporting the capability of storing and fetching streams of data with strict synchronicity and isochronicity requirements. In order to fulfill these requirements, the GigaView parallel image server architecture relies on arrays of intelligent disk nodes, with each disk node being composed of one processor and one disk. This paper analyzes, through simulation, the real-time behavior of the GigaView in terms of delay and delay jitter. For a high-end GigaView architecture, consisting of 16 disks and T9000 transputers, we evaluate stream frame access times under various parameters, such as load factors, frame size, stream throughput, and synchronicity requirement

Dynamic load balancing of parallel cellular automata

We are interested in running in parallel cellular automata. We present an algorithm which explores the dynamic remapping of cells in order to balance the load between processing nodes. The parallel application runs on a cluster of PCs connected by Fast-Ethernet. A general cellular automaton can be described as a set of cells where each cell is a state machine. To compute the next cell state, each cell needs some information from neighbouring cells. There are no limitations on the kind of information exchanged nor on the computation itself. Only the automaton topology defining the neighbours of each cell remains unchanged during the automaton's life. As a typical example of cellular automation we consider the image skeletonization problem. Skeletonization requires spatial filtering to be repetitively applied to the image. Each step erodes a thin part of the original image. After the last step, only the image skeleton remains. Skeletonization algorithms require vast amounts of computing power, especially when applied to large images. Therefore, skeletonization application can potentially benefit from the use of parallel processing. Two different parallel algorithms are proposed, one with a static load distribution consisting in splitting the cells over several processing nodes and the other with a dynamic load balancing scheme capable of remapping cells during the program execution. Performance measurements show that the cell migration doesn't reduce the speedup if the program is already load balanced. It greatly improves the performance if the parallel application is not well balance

Giga view parallel image server performance analysis

Professionals in various fields such as medical imaging, biology and civil engineering require rapid access to huge amounts of uncompressed pixmap image data. Multi-media interfaces further increase the need for large image databases. In order to fulfill these requirements, the GigaView parallel image server architecture relies on arrays of intelligent disk nodes, each disk node being composed of one processor and one disk. This contribution analyzes through simulation and experimentation the behavior of the GigaView under single and multiple requests, and compares it to the behavior of RAID servers. It evaluates image visualization window access times under various parameters such as load factors and the number of cooperating disk nodes. Under single request, the GigaView image server can be modeled as a single high-throughput low-latency secondary storage device. Under multiple requests, the notions of utilization and maximum sustainable throughput define accurately the behavior of the GigaView

Synthesizing parallel imaging applications using the CAP Computer-Aided Parallelization tool

Imaging applications such as filtering, image transforms and compression/decompression require vast amounts of computing power when applied to large data sets. These applications would potentially benefit from the use of parallel processing. However, dedicated parallel computers are expensive and their processing power per node lags behind that of the most recent commodity components. Furthermore, developing parallel applications remains a difficult task. In order to facilitate the development of parallel applications, we propose the CAP computer aided parallelization tool which enables application programmers to specify at a high level of abstraction the flow of data between pipelined parallel operations. In addition, the CAP tool supports the programmer in developing parallel imaging and storage operations. CAP enables combining efficiently parallel storage access routines and image processing sequential operations. The paper shows how processing and I/O intensive imaging applications must be implemented to take advantage of parallelism and pipelining between data access and processing. The paper's contribution is: (1) to show how such implementations can be compactly specified in CAP; and (2) to demonstrate that CAP specified applications achieve the performance of custom parallel code. The paper analyzes theoretically the performance of CAP specified applications and demonstrates the accuracy of the theoretical analysis through experimental measurement

Utjecaj toksičnosti metala na reprodukcijsku funkciju u muškaraca

A combination of genetic, environmental and lifestyle factors contributes to adverse effects on the reproductive health in men. Metals are pervasive in food, water, air, tobacco smoke, and alcoholic beverages. Experimental studies suggest that many metals have adverse effects on the male reproductive function. However, information about reproductive effects of human exposure to metals is scarce and/or inconsistent. This review summarises the information from epidemiological studies of the effects of metal exposure on reproductive function in men. Factors capable of affecting these relationships were identifi ed and discussed. A particular attention is given to the studies considering influence of concomitant exposure to various metals. These studies have generally confirmed that even moderate- to low-level exposure to lead affects certain reproductive parameters, and that exposure to cadmium affects the prostate function and serum testosterone levels. Adverse effects of mercury, manganese, chromium and arsenic on semen quality and altered serum hormone are less well documented. There is no clear evidence that boron exposure may impair reproductive health in men. Only a few studies have investigated reproductive effects of concomitant exposure to several metals and controlled for potential confounders. Future studies should consider the contribution of combined exposure to various metals and/or other factors that may influence individual susceptibility to reproductive health impairment in men.Postoje indikacije da kombinacija genetskih, okolišnih i čimbenika načina života pridonosi uočenom poremećaju reprodukcijskog zdravlja u muškaraca. Metali su široko rasprostranjeni u čovjekovu okolišu te u hrani, vodi, zraku, cigaretnom dimu i alkoholnim pićima. Rezultati eksperimentalnih istraživanja sugeriraju štetne učinke većine ispitivanih metala na mušku reprodukcijsku funkciju. Međutim, odgovarajuća su istraživanja u ljudi oskudna. Ovaj rad sažima rezultate dosadašnjih epidemioloških istraživanja o učincima izloženosti metalima na mušku reprodukcijsku funkciju. Poseban naglasak dan je istraživanjima koja su razmatrala utjecaj istodobne izloženosti različitim metalima uz čimbenike čovjekova načina života i njihovo međudjelovanje na reprodukcijske učinke. Objavljeni rezultati daju dovoljno dokaza o štetnom djelovanju olova i žive na neke reprodukcijske parametre te kadmija na poremećaj prostate i razinu testosterona u serumu, čak u uvjetima umjerene do niske razine izloženosti. Manje je dokaza o štetnom djelovanju na kvalitetu sjemena i razinu spolnih hormona nađeno za mangan. Podaci koji upućuju na moguće štetno djelovanje arsena ili kroma nisu dosljedni, dok o štetnom djelovanju bora na mušku reprodukcijsku funkciju nema jasnih podataka. Utjecaj potencijalno uzročnih varijabli uzet je u obzir samo u nekoliko radova. Stoga buduća istraživanja poremećaja reprodukcijskog zdravlja u muškaraca trebaju razmatrati doprinos istovremene izloženosti različitim metalima koji u kombinaciji s ostalim čimbenicima mogu utjecati na osobnu (pre)osjetljivost

[The conception of electronic circuits]

Gives a summary of the major ideas which affect the design of circuit boards. It includes available technologies, and their external characteristics, both indispensible to a circuit designer. The different integration levels and corresponding logic functions, and the production of combination and sequential types of circuit are also covered. Various technology families are outlined and some details are given of their power and speed capabilities and a table illustrates the different integration levels. Logic methods are discussed, with some typical circuits and there is brief discussion of programmable circuits and various available forms of logic. Programmed logic is discussed further, together with microprogramming and the general principles governing electronic circuit design are outlined.Francai

The Giga View Multiprocessor Multidisk Image Server

ABSTRACT Professionals in various fields such as medical imaging, biology, and civil engineering require rapid access to huge amounts of pixmap image data. Multimedia interfaces further increase the need for large image databases. To fulfill these requirements, the GigaView parallel image server architecture relies on arrays of intelligent disk nodes, each disk node being composed of one processor and one disk. This contribution reviews the design of the GigaView hardware and file system, compares it to other storage servers available on the market, and evaluates fields of applications for the architecture