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We document the protocols and methods for the production of immortalized cell lines of human neural stem cells from the human fetal central nervous system (CNS) cells by using a retroviral vector encoding v-myc oncogene. One of the human neural stem cell lines (HB1.F3) was found to express nestin and other specific markers for human neural stem cells, giving rise to three fundamental cell types of the CNS: neurons, astrocytes, and oligodendrocytes. After transplantation into the brain of mouse model of stroke, implanted human neural stem cells were observed to migrate extensively from the site of implantation into other anatomical sites and to differentiate into neurons and glial cells. [ABSTRACT FROM AUTHOR]

Freehand sketch is a fast and easy tool for idea development and communication, especially in the critical front-end or predevelopment stages. While it is important to any designer, lacking of appropriate mechanism for correction in fundamental design education makes even professionals hard to precisely handle accuracy of perspective sketch. Based on two-point perspe-ctive method and using cubic shape as subject, this research develops reverse drawing approach and accordingly establishes a digital training system for freehand sketch practice, namely Perspective Practice. Users can operate con-ventional pen and paper for input and the system automatically illustrates on screen a correct perspective drawing on top of the sketch done by the user, pointing out the concept or technique for improvement. The system provides users with ways in understanding their current skills and guidelines for impro-vement, through which the efficacy in digital technical training can be enhanced. [ABSTRACT FROM AUTHOR]

Bekk Consulting (BEKK), a Norwegian IT- and management consulting company changed their way of running projects from traditional waterfall to a more agile approach. It took more than a year getting the whole company onboard and more than two years to convince most of the customers. We are still learning, adjusting and improving the way we run our projects - with focus on the outcome over delivering features. BEKK is a Norwegian IT- and management consulting company leveraging on the intellectual capital of their more than 160 employees. With specialist like graphic designers through system developers, usability experts, project managers and management consultants we create cross-functional teams running projects to high business value solutions, based on internet technology. We will later in this report discuss what were the drivers for this transition, but first we need to understand that it's about creating VALUE for the customer. [ABSTRACT FROM AUTHOR]

This experience report is about how one project in Norway made an agile approach to specifying software requirements for a new intranet. Rather than spending months on trying to detail all requirements and aspects of the solution, the team spent a few weeks specifying a prioritized list of high-level requirements. Further details will emerge by face-to-face communication through the iterations of the project quickly turning in to valuable working software for the customer. [ABSTRACT FROM AUTHOR]

In this paper, we propose the Channel sounding scheme which is made for ideal communication between some application as well as the short distance of high speed data transmission in MIMO-OFDM system for Wireless PAN. This method is able to perceive the duration of the impulse response through the delaying of power delay profile, modeled a power delay profile which has an attenuate characteristic, and obtained the coefficient of channel response by ML (maximum likelihood). Through the amplitudes, phases and delays associated with each multipath component which were acquired from this Channel sounding scheme, we can describe the wave propagation characteristics of channels between the transmitter and receiver so that the receiver could enhance not only the reliability but also the ability of communication link. [ABSTRACT FROM AUTHOR]

The total score of items fitting a Rasch model (RM) satisfies assumptions relating to validity and a number of technical requirements. For this reason, the RM is often used as a "gold standard" expressing ideal measurement requirements. [ABSTRACT FROM AUTHOR]

Small intestine submucosa (SIS) derived from the submucosal layer of porcine intestine cause minimum immune response as acellular collagen based matrix1,2 and moreover is a biodegradable.3 SIS consists of types I and III collagens above 90% and small amounts of types IV, V, and VI collagens.4 In addition, SIS contains a wide variety of cytokine such as basic fibroblast growth factor (bFGF), transforming growth factor-β (TGF-β), epidermal growth factor (EGF), vascular endothelial growth factor (VEGF), and insulin-like growth factor-1 (IGF-1) as well as glycosaminoglycans, fibronectins, chondroitin sulfates, heparins, heparin sulfates, and hyaluronic acids.5,6 These constituents are well known to play an important role for tissue remodeling and wound healing. SIS has been used as commercial goods in practical biomedical fields such as the repair of numerous body tissues including musculotendinous structures, lower urinary tract reconstruction, dura mater replacement, vascular reconstruction, and the repair of full and partial thickness skin wounds.7-9 [ABSTRACT FROM AUTHOR]

Intervertebral discs (IVD) are specialized structures to anchor adjacent vertebral bodies conferring flexibility and providing mechanical stability during axial compression1. Degeneration of IVD results in discogenic low back pain and limited mobility. Very recently, to overcome limited success of current surgical treatment focused on fusion, few studies have been started by tissue engineering technique2,3. It has been recognized that tissue engineering offers an alternative techniques to whole organ and tissue transplantation for diseased, failed or malfunctioned organs4,5. In tissue engineering of IVD, presence of disc cells harvested from IVD tissue of donor and proper scaffold is needed6-8. [ABSTRACT FROM AUTHOR]

This paper deals with the initial and loading path induced anisotropy for a sub angular granular material, Hostun sand. The "quasi" elastic properties observed in the small strain domain (<10−5 m/m) are considered. A "static and dynamic" triaxial device is used for the experimental campaign. First, the five parameters of the transverse isotropic elastic compliance tensor are experimentally obtained. The experimental investigations consist in applying small axial cyclic loadings (strain amplitude cycle εsa≅ 10−5 m/m) and four types of dynamic wave propagations, generated by piezoelectric sensors (compressive and shear waves in axial and radial directions). The followed isotropic and deviatoric stress path underlines the effects of respectively inherent and induced anisotropy. A rheological hypoelastic model, called DBGS model, which takes into account the stress induced anisotropy, is firstly described. This model is not sufficient to properly describe experimental results at isotropic stress state as well as thus obtained during deviatoric stress path for medium and large strain. Then, an extension of the model is proposed, called DBGSP model, where strain induced anisotropy is taken into account. The concept of virtual strain induced anisotropy is introduced in this rheological hypoelastic model developed at ENTPE, and the ability of the model to foresee experimental behaviour is checked. [ABSTRACT FROM AUTHOR]

Tests on air dried Hostun and Toyoura sands and on two moist mixtures of mainly Hostun sand with Kaolin clay were performed with a precision hollow cylinder device "T4C StaDy". Viscous properties are investigated through creep tests with and without rotation of stress principle axes (i.e. during triaxial compression - TC - and torsional shear - TS - tests) from small strain domain (some 10-5 m/m) up to large strain (some 10-2 m/m). A simplified version of the viscous evanescent model (VE), developed specifically at DGCB/ENTPE to model the peculiar viscous behaviour of sand, can be considered for creep tests. Good correlations are obtained between simulated and experimental creep strains for all the materials tested. A simple relation is confirmed for the viscous parameter of the VE model for sands (considering tests with and without rotation of stress principle axes) as well as for sand/clay mixtures (considering tests without rotation of stress principle axes). [ABSTRACT FROM AUTHOR]

By combining puzzles as the metaphor as well as the mechanism, design puzzles provide an interesting computational method to both design exploration and representing the design ideas via collage images. By using multi-touch technology such as FTIR, this research implements a physical controlling device called Collage Tables (CoTa) for directly manipulating the design collages, which using the mechanism developed over the years from design puzzles. By focusing on the interactive behaviours of design collage, the exploration rules as well as puzzle rules are further developed and elaborated in this paper. The exploration search mechanism and the system (CoTa) in both hardware and software part of CoTa is also evaluated and computed for the purpose of reification. A set of possible interaction is also documented in this paper. [ABSTRACT FROM AUTHOR]

KIMM (Korea Institute of Machinery and Materials) has been practicing a project on the development of an e-Engineering framework for automotive module design from 1 year ago. In this project, several advanced technologies for e-Engineering such as intelligent software agents, Internet/Web, process-flow, optimization, PDM (Product Data Management) & CAE (Computer Aided Engineering) interfaces, and database management are included. The framework especially focuses on initial prototype design stage of automotive suspension module. A kind of process oriented framework has been developed and a new kind of function oriented one, which means the project's main goal can be achieved by each autonomous PAS (Process/Analysis Server) agent's cooperation, is designed and developed on the base of JADE (Java Agent DEvelopment Framework) and VivAce(Vivid Agent computing environment). Each framework aims at providing integrated or individual engineering services between car vendor and 1st tier module maker or between 1st tier and 2nd tier module maker. [ABSTRACT FROM AUTHOR]

Heterogeneous access networks in B3G networks can provide each proper network service to mobile users. Furthermore, mobile users can use not only a unique access network service, but also different hetero network services by connecting another access network. For using another access network service, mobile terminals must support hetero network system techniques. Hence, by this multiple system modes, mobile terminals are able to implement ISHO (Inter System Handover) for changing the network service. In the heterogeneous access network environment, new resource management can be adopted to control QoS management. In this paper, we propose a resource balancing management scheme by the ISHO to increase the network availability. From the numeric analysis, we compare the proposed scheme with a current scheme. [ABSTRACT FROM AUTHOR]

Project of Common Criteria (CC) based evaluations of an IT security product/system takes so much cost and time that effective evaluation project management is strongly required. We present a CC based security evaluation management system (CC-SEMS) that is useful for evaluation facilities and developers of IT security product. Evaluation activity program, evaluation plan, XML-DTD of deliverable, management object, and evaluation DB are proposed as distinct approaches of CC-SEMS. [ABSTRACT FROM AUTHOR]

With the characteristics of ANN's strong capability on nonlinear approximation, a new method by combining an artificial neural network with back-propagation learning algorithm and modal analysis via finite element model of cracked rotor system is proposed for fast identification of crack fault with high accuracy in rotating machinery. First, based on fracture mechanics and the energy principle of Paris, the training data are generated by a set of FE-model-based equations in different crack cases. Then the validation of the method is verified by several selected crack cases. The results show that the trained ANN models have good performance to identify the crack location and depth with higher accuracy and efficiency, further, can be used in fast identification of crack fault in rotating machinery. [ABSTRACT FROM AUTHOR]

Electromagnetic noise, unbalanced rotor noise and injuring bearing noise are three types of noise in faulting electromotor. An adaptive wavelet neural network is proposed to identify these noises. The process of wavelet-based feature extraction of signal is integrated into one part of neural network. During network's training course the wavelet's scale and shift parameters can be adaptively adjusted to fit input signal so that signal's feature could be extracted in maximum limit. The network's second part then uses these feature information to realize the identification of noise signal. The identification result of three types of noise of electromotor demonstrates that this neural network can give accurate identification result with high probability. [ABSTRACT FROM AUTHOR]

Persuasive technologies can be useful to modify behaviors related to energy usage. In this paper, we present the PowerHouse a computer game designed to influence behaviors associated with energy use and promote an energy-aware lifestyle among teenagers. This prototype game aims to influence a set of target activities in the home using several persuasive techniques. Employing the format of a reality TV show (docu soap), the game informs implicitly and explicitly about various energy-efficient actions. We discuss our overall game design and its advantages and disadvantages in relation to the methods we have employed in the game. [ABSTRACT FROM AUTHOR]

Heating is a significant expenditure of many households today but the actual power consumption of the heating devices are seldom recognized. To help people understand and reflect upon their domestic energy consumption, we have designed an electrical radiator that emits heat entirely from light bulbs. This appliance responds to temperature changes in the room via sensors. The idea was to combine the product semantics of lamps and radiators and direct focus on the latter neglected product category. We argue that by re-designing domestic appliances adding means to visualize energy consumption in engaging and interesting ways it is possible to make energy utilization less abstract and easier to comprehend. [ABSTRACT FROM AUTHOR]

Coverage is a very important issue in wireless sensor networks. Current literature defines a point to be covered if it is within the sensing radius of at least one sensor. This is a conservative definition of coverage and we have previously proposed a new notion of information coverage. Compared with the conventional definition of coverage, a point can still be information covered even if it is not within the sensing disk of any sensor. The density requirements for complete information coverage of a field are analyzed and simulated for a random sensor deployment. Our results show that significant savings in terms of sensor density can be achieved with information coverage. [ABSTRACT FROM AUTHOR]

Ortho-photos contain highly valuable data with high potential. They are useful in various applications, such as the creation of image maps and texture information in Geographic Information System (GIS). The Z-buffer method has been one of the most popular methods for the true ortho-photo generation. However, it has strict requirements regarding the Digital Surface Model (DSM) cell size. Furthermore, Z-buffer Method have false visibility problmes in narrow vertical structrues. The Z-buffer Method can be modified to avoid this problem using pseudo points along vertical surfaces. However, this method still has problems with certain DSM resolutions. This study implements two technical approaches for true ortho-photo generation u(l) the horizontal position of a point along the search path reaches the nadir point in the object space sing high resolution satellite imagery. The first approach deals with the scan line search method, which is required since each scan line has its own perspective center. The other approach is concerned with occlusion detection, which is required for the creation of true ortho-photos. Final experimental results with real data have demonstrated the feasibility of this proposed true ortho-photo generation methodology. [ABSTRACT FROM AUTHOR]

In this paper, we derive and analyze network availability for sensor grids by considering an elaborate energy consumption model. Sensor grids that form chain topologies are compared for two widely known grid traversal models, namely staircase and Delannoy number. Based upon the mathematical model, we analyze two sleep modes, viz, synchronous and asynchronous for their effects on the network availability of sensor grids with regard to energy conservation and packet loss. We also propose a non-uniform, asynchronous sleep scheme in sensor grids which allows nodes to sleep in a manner such that nodes closer to the gateway sleep less than the nodes in the fringes. The performance results show that the proposed scheme prolongs network availability effectively in sensor grids. [ABSTRACT FROM AUTHOR]

The purpose of this study was to develop a process management system to manage ingot fabrication and the quality of the ingot. The ingot is the first manufactured material of wafers. Trace parameters were collected on-line but measurement parameters were measured by sampling inspection. The quality parameters were applied to evaluate the quality. Therefore, preprocessing was necessary to extract useful information from the quality data. First, statistical methods were used for data generation, and then modeling was performed, using the generated data, to improve the performance of the models. The function of the models is to predict the quality corresponding to control parameters. [ABSTRACT FROM AUTHOR]

As argued in this paper, a decision support system based on data mining and knowledge discovery is an important factor in improving productivity and yield. The proposed decision support system consists of a neural network model and an inference system based on fuzzy logic. First, the product results are predicted by the neural network model constructed by the quality index of the products that represent the quality of the etching process. And the quality indexes are classified according to and expert's knowledge. Finally, the product conditions are estimated by the fuzzy inference system using the rules extracted from the classified patterns. We employed data mining and intelligent techniques to find the best condition for the etching process. The proposed decision support system is efficient and easy to be implemented for process management based on an expert's knowledge. [ABSTRACT FROM AUTHOR]

The development of efficient Quality of Service (QoS) routing algorithms in high speed networks is very difficult since divergent services require various quality conditions. If the QoS parameter we concern is to measure the delay on that link, then the routing algorithm obtains the Least Delay (LD) path. Meanwhile, if the parameter is to measure of the link cost, then it calculates the Least Cost (LC) path. The Delay Constrained Least Cost (DCLC) path problem of the mixed issues on LD and LC has been shown to be NP-hard. The path cost of LD path is relatively more expensive than that of LC path, and the path delay of LC path is relatively higher than that of LD path in DCLC problem. In this paper, we propose Estimated Path Selection (EPS) algorithm for the DCLC problem and investigate its performance. It employs a new parameter which is probabilistic combination of cost and delay. We have performed empirical evaluation that compares our proposed EPS with the DCUR in various network situations. It significantly affects the performance that the normalized surcharge is improved up to about 105%. The time complexity is O(l + nlogn) which is comparable to well-known previous works. [ABSTRACT FROM AUTHOR]

This paper proposes a localized recursive estimation scheme for parameter estimation in wireless sensor networks. Given any parameter occurred at some location and time, a number of sensors recursively estimates the parameter by using their local measurements of the parameter that is attenuated with the distance between a sensor and the target location and corrupted by noises. Compared with centralized estimation schemes that transmit all measurements to a sink (or a fusion center), the recursive scheme needs only to transmit the final estimate to a sink. When a sink is faraway from the sensors and multihop communications have to be used, using localized recursive estimation can help to reduce energy consumption and reduce network traffic load. Furthermore, the most efficient sequence of sensors for estimation is defined and the necessary condition for such a sequence is determined. Some numerical examples are also provided. By using some typical industrial sensor parameter values, it is shown that recursive scheme consumes much less energy when the sink is three hops or more faraway from the local sensors. [ABSTRACT FROM AUTHOR]

This paper proposes the concept of information exposure for a point and for a path based on estimation theory. The information exposure of a point is defined as the probability that the absolute value of estimation error is less than some threshold; and the information exposure for a path is the average information exposure of all points along the path. The higher the information exposure, the higher the confidence level that some information of a target is exposed and the better the target is monitored. An approximation algorithm is proposed to solve the problem of finding the worst (best) information exposure path in wireless sensor networks, and its performance is evaluated via simulations. Furthermore, a heuristic for adaptive sensor deployment is proposed to increase the information exposure of the worst information exposure path. [ABSTRACT FROM AUTHOR]

In this paper we consider latent variable models and introduce a new -likelihood concept for estimating the distribution over hidden variables. One can derive an estimate of parameters from this distribution. Our approach differs from the Bayesian and Maximum Likelihood (ML) approaches. It gives an alternative to Bayesian inference when we don't want to define a prior over parameters and gives an alternative to the ML method when we want a better estimate of the distribution over hidden variables. As a practical implementation, we present a -updating algorithm based on the mean field theory to approximate the distribution over hidden variables from the -likelihood. This algorithm captures some of the correlations among hidden variables by estimating reaction terms. Those reaction terms are found to penalize the likelihood. We show that the -updating algorithm becomes the EM algorithm as a special case in the large sample limit. The useful behavior of our method is confirmed for the case of mixture of Gaussians by comparing to the EM algorithm. [ABSTRACT FROM AUTHOR]

With the multicast technology, demands for the real-time group applications through multicasting is getting more important. An essential factor of these real-time strategy is to optimize the Delay- and delay Variation-Bounded Multicast Tree (DVBMT) problem. In this paper, we propose a new algorithm for the DVBMT solution. The proposed algorithm outperforms other algorithms up to 9%~25% in terms of the delay variation. [ABSTRACT FROM AUTHOR]

The core-based multicast routing protocol plays a significant role in many multimedia applications such as video-conferencing, replicated database updating and querying, and etc. However, existing core-based multicast routing protocols construct only the shortest paths between the core and the members in a multicast group without optimizing the quality of service requirements. In this paper, we propose an efficient algorithm for multicast delay variations and tree cost. The efficiency of our algorithm is verified through the performance evaluation and the enhancements are up to about 2.5% ~ 4.5% and 3.8% ~ 15.5% in terms of the multicast delay variation and the tree cost, respectively. The time complexity of our algorithm is O(m(l + n log n)). [ABSTRACT FROM AUTHOR]

We have developed and evaluated an efficient heuristic algorithm to construct a multicast tree with the minimum cost. Our algorithm uses multiple candidate paths to select a path from source to each destination, and works on directed asymmetric networks. We also show that our proposed algorithm have a perform gain in terms of tree cost for real life networks over existing algorithm. The time complexity of our algorithm is O( D (m + nlogn) ) for a m-arc n-node network with D number of members in the multicast group, and is comparable to well-known algorithm, TM [13], for a multicast tree construction in terms of the time-complexity. We have performed empirical evaluation that compares our algorithms with the others on large networks. [ABSTRACT FROM AUTHOR]

To decide whether a line graph (hence a claw-free graph) of maximum degree five admits a stable cutset has been proven to be an NP-complete problem. The same result has been known for K4-free graphs. Here we show how to decide this problem in polynomial time for (claw, K4)-free graphs and for a claw-free graph of maximum degree at most four. As a by-product we prove that the stable cutset problem is polynomially solvable for claw-free planar graphs, and for planar line graphs. Now, the computational complexity of the stable cutset problem restricted to claw-free graphs and claw-free planar graphs is known for all bounds on the maximum degree. Moreover, we prove that the stable cutset problem remains NP-complete for K4-free planar graphs of maximum degree five. [ABSTRACT FROM AUTHOR]

Graph decompositions such as decomposition by clique separators and modular decomposition are of crucial importance for designing efficient graph algorithms. Clique separators in graphs were used by Tarjan as a divide-and-conquer approach for solving various problems such as the Maximum Weight Stable Set (MWS) Problem, Coloring and Minimum Fill-in. The basic tool is a decomposition tree of the graph whose leaves have no clique separator (so-called atoms), and the problem can be solved efficiently on the graph if it is efficiently solvable on its atoms. We give new examples where the clique separator decomposition works well for the MWS problem which also improves and extends various recently published results. In particular, we describe the atom structure for some new classes of graphs whose atoms are P5-free (the P5 is the induced path with 5 vertices) and obtain new polynomial time results for MWS. [ABSTRACT FROM AUTHOR]

At present the scale of multimedia and communication systems has become more and more complicated due to their fast developments. In order to handle diverse functions and shorten system development time, the ability to reconfigure system architecture becomes an important and flexible design consideration. In this paper, we propose a novel reconfigurable processing unit, FMRPU, which is a fine-grain with multi-context reconfigurable processing unit targeting at high-throughput and data-parallel applications. It contains 64 reconfigurable logic evel connectivity. According to the simulation results, the longest routing arrays, 16 switch boxes, and connects with each other via three hierarchical-lpath of FMRPU only takes 6.5 ns at 0.35 processes, which is able to construct the required logic circuit efficiently. To compare with same kind devices in dealing with Motion Estimation operations, the performance is raise to 17% and has excellent performance in executing DSP algorithms. [ABSTRACT FROM AUTHOR]

The key point to reach interoperability over distributed ontologies is the mediation between them, called ontology mapping. Absolutely manually specified mapping is tedious and time consumption. Additional, how to ensure the consistency and deal with error prone in manual process, further how to maintain the mapping with the evolution of ontologies are all beyond manual work. Therefore, it is indeed necessary to automatically discover the mapping between ontologies so that mergence and translation of different ontology-based annotations become possible. Existing (semi-)automatic processing system are restricted to limited information, which depress the performance especially when the taxonomy structures have little overlapping or the instances have few commons. In this paper, based on Bayesian decision theory, we propose an approach called RiMOM to automatically discover mapping between ontologies. RiMOM treats the entire mapping problem as a decision problem instead of similarity problem in previous work. It explicitly and formally gives a complete decision model for ontology mapping. Based on shallow NLP, this paper also introduces a method to deal with instances heterogeneity, which is a long-standing problem for information processing. Experiments on real world data show that RiMOM is promising. [ABSTRACT FROM AUTHOR]

This chapter assumes that the return to R&D capital is driven by a technological factor that follows a mean-reverting process. R&D capital also exhibits both irreversibility and externality through the learning-by-doing effect. The optimal paths for R&D capital under both the decentralized and the centralized economy are derived and then compared. It is found that an equal rate of investment tax credits should be given to both costlessly reversible investments and irreversible ones, and this common rate is unrelated to the parameters that characterize the mean-reverting process. [ABSTRACT FROM AUTHOR]

This chapter assumes that a firm facing technological uncertainty must decide when to purchase R&D capital. R&D capital exhibits both irreversibility and externality through the learning-by-doing effect. The combination of irreversibility and uncertainty drives agents to be more prudent, i.e. the maxim 'better safe than sorry' applies. This maxim is more important if uncertainty is greater, technology progresses at a lower pace, the externality is stronger, or a catastrophic event is less likely to occur. A firm ignoring the externality will both invest later and disinvest earlier than a social planner who internalizes the externality. An equal rate of investment tax credits should be given to both costlessly reversible investments and irreversible ones, and the same rate of taxation should be imposed on disinvestment. [ABSTRACT FROM AUTHOR]

Neural crest cells migrate from the dorsal aspect of the neural tube and differentiate into a variety of cell types in different locations. These cell types include peripheral neurons and glia (Schwann cells), melanocytes, endocrine cells, smooth muscle, skeletal muscle and bone (1). In vivo lineage tracing and in vitro clonal analyses in avian embryos have indicated that many neural crest cells are multipotent (2,3) and transplantation and culture studies suggest that the fate of multipotent neural crest cells can be determined by the environment (4-6). [ABSTRACT FROM AUTHOR]

Constructing minimum ultrametric trees from distance matrices is an important problem in computational biology. In this paper, we examine its computational complexity and approximability. When the distances satisfy the triangle inequalities, we show that the minimum ultrametric tree problem can be approximated in polynomial time with error ratio 1.5(1 + ⌈log n⌉), where n is the number of species. We also developed an efficient branch and bound algorithm for constructing the minimum ultrametric tree for both metric and nonmetric inputs. The experimental results show that it can find an optimal solution for 25 species within reasonable time, while, to the best of our knowledge, there is no report of algorithms solving the problem even for 12 species. [ABSTRACT FROM AUTHOR]

This article presents information on digital-to-analog conversion (DAC). All electrical signals in the real world are analog in nature, and their waveforms are continuous in time. However, most signal processing is done numerically in a sample data form in discrete time. Because digital numbers are limited in length, the number of different possible DAC output levels depends on the number of bits used to form digital input word. DAC performance is limited by two factors. One is the static linearity in representing digital numbers with a finite number of discrete output levels, and the other is the dynamic accuracy in the transition from one level to another.

Friction Stir Welding (FSW), invented by W.M. Thomas et al. [1], can produce superior mechanical properties in the weld zone. The purpose of this paper is to find the optimum operating conditions of FSW process for two plates of aluminum alloy AA5083 welded in butt joint. In the FSW procedure, there were four major controllable four-level factors, i.e., the tool rotation speed, transverse speed (feed rate), tool tilt angle with respect to the workpiece surface and pin tool length, as shown in Table 1. [ABSTRACT FROM AUTHOR]

The article presents the poem "Louise in Love," by Mary Jo Bang. First Line: Much had transpired in the phantom realm: Last Line: fish hook.

An abstract of the article "Cellular and Molecular Biology of Orphan G Protein-Coupled Receptors," by Da Young Oh and colleagues is presented.

The article presents the poem "The Star's Whole Secret," by Mary Jo Bang. First Line: Did she drink tea? Yes, please. And after; Last Line: of a fire.

The article presents the poem "Like a Fire in a Fire," by Mary Jo Bang. First Line: They were difficult to find. It was summer so; Last Line: of shoulder with faint smell of soap.

The article presents the poem "The Dog Bark," by Mary Jo Bang. First Line: Louise peered into the corner of the cabinet; Last Line: of compelling circumference.

The article presents the poem "The Constant Bride," by Mary Jo Bang. First Line: Do you understand the concept? The marvel? Tender at the neck, Last Line: from which to choose: sleep and may she never wake.