Top PDF Design Considerations in Linear Microdensitometry

Design Considerations in Linear Microdensitometry

Design Considerations in Linear Microdensitometry

TABLE OF FIGURES Number Page Title 1 Comparison 2 General System Realization k 3 Linear System Realization 5 k Stationary Linear 6 5 General Optical Model 8 6 General Microdensitometer M[r]

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Memorial design : considerations for Christchurch

Memorial design : considerations for Christchurch

Both new and traditional monuments continue to be built. Strakosch (2010: 272) maintains ‘...there is not a simple linear movement from traditional to counter- monumental forms’. This is demonstrated by the vacillation in the memorial processes described above. Each of the design process examples given have all, at some point, been billed as counter monuments. However, if the overtly didactic monuments of traditional commemoration and the most radical counter- monuments were placed at either end of a memorial design spectrum, the examples given above would fall somewhere between the two. In these cases memorialisation processes have invariably brought about compromise in which relatively open, abstracted memorial forms are bound to some form of exegetic appendage. Permanence through the use of stone or concrete, figurative sculpture and plaques are often incorporated, as the traditional monument would demand, to guarantee a long lasting presence and informative value. Young alludes to this inevitable compromise when discussing the fate of radical counter-monuments; those which have been intentionally designed to disappear.
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Technical Considerations for the Design of Smart Apparel for the Overweight

Technical Considerations for the Design of Smart Apparel for the Overweight

For rehabilitation purposes, Gibbs and Asada developed wearable conductive fiber sensors for multi-axis joint angle measurement for continuous monitoring of joint motion. They applied the conductive fiber sensors to skin-tight pants for measuring the joint angles of the lower body. Silver plated nylon 66 yarn having an impedance of approximately 3.6Ω/cm was used as the sensor. They formulated an automated registration algorithm considering a sensitivity shift and arrangement of sensors. They showed that the quadratic predictor is better than the linear predictor through comparing the results of goniometer output, linear model estimation and quadratic model estimation in a single-axis knee joint angle. Sensing output errors caused by repetitive dressing and undressing of the sensing garment were observed. Sensors monitored the movement of a double axis hip joint. There was no significant difference between the quadratic predictor and the linear predictor for the output in the double axis hip joint (P. T. Gibbs and H. H. Asada).
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Design Considerations for Blast Loads in Pressure Vessels

Design Considerations for Blast Loads in Pressure Vessels

The dynamic analysis is accomplished using the explicit finite-element code ParaDyn, which is the massively parallel version of DYNA3D [13]. Resulting P-T history from CTH hydrodynamics code is input to the structural dynamics code. DYNA3D is a non-linear, explicit, Lagrangian finite element analysis code used for three-dimensional transient structural mechanics. Numerical simulation requires the use of large, detailed meshes in order to include engineering features such as the bolted port connections. The vessel, shown in Figures 9 and 10, is a 72-inch inside diameter, 2.5 inch thick spherical shell with 5 ports. Each port has a steel cover bolted to a nozzle with 72-1.25-inch diameter bolts. The four side ports are entry/exit locations for the x-ray beams, and contain radiographic hardware and fragment shielding. The fifth port on top of the vessel is used for general access. Welded areas of the vessel, including the nozzle-to-vessel welds and the girth weld, are included in the model and appear as magenta regions.
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Design Considerations Of Mems Piezoelectric Accelerometers

Design Considerations Of Mems Piezoelectric Accelerometers

Korbinian Kunz et al reported the first micromachined triaxial single mass accelerometer with integrated piezoelectric thin film detectors [8]. The accelerometer Korbinian Kunz et al reported the first micromachined triaxial single mass accelerometer with integrated piezoelectric thin film detectors [8]. The accelerometer consists of a 1.2 mg mass suspended by four beams. The charge sensitivity in the vertical direction is 22pC/g and in the parallel direction it is 8pC/g. L.-P. Wang et al developed MEMS accelerometers based on piezoelectric lead zirconate titanate (PZT) thick films with annular diaphragm sensing structures [9]. The design provides good sensitivity along one axis, with low transverse sensitivity and good temperature stability. Measured sensitivities range from 0.77 to 7.6 pC/g for resonant frequencies from 35.3 kHz to 3.7 kHz. Later E.C.C. Hindrichsen et al [10] developed a bulk-micromachined piezoelectric MEMS accelerometer with screen printed piezoelectric Pb(ZrxTil )O3(PZT) thick film (TF) as the sensing material. The resonance frequency is found to be 17.5 kHz and the sensitivity 4.15 mV/g for a single beam. We have developed the MEMS accelerometer with larger proof mass and the suspension beams with added thigh section. In this research initially we have done the analytical calculation (theoretical design) of the MEMS accelerometer and secondly FEM analysis is done to arrive at a final device dimensions and the materials. Finally the device is fabricated with the specified dimensions and materials and we have tested the device using the shaker set up at the specified operating frequency range. Through proper design and selection of materials, we could achieve the high sensitivity within the frequency range dc-200Hz. In general piezoelectric accelerometer is designed based on two factors, the mechanical structure and dimensions of the sensors. The structure of the accelerometer consists of a proof mass supported by the four crab leg flexures (fig.1). The mass is squared and the flexures are of crab leg shape. The shape of the flexures is chosen depending on its force deflection linear characteristic. The crab leg beams consists of a thigh section and the shin section. These beams provide stiffness and the means of movement of proof mass in accelerometer. The performance of accelerometer is
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Design Considerations of Piezo Stepping Actuator

Design Considerations of Piezo Stepping Actuator

A piezo actuator converts electrical energy into mechanical energy and vice-versa. A piezoelectric actuator is one device that converts electrical energy into mechanical energy which here is observed in the means of displacement. Actuators are specifically designed which consists of stacked piezoelectric actuators to perform the required action. Chen Sheng Ting et al. [1] has developed a displacement mechanism system using linear stepping motors. In this paper, voltage controlled pulse width modulation (PWM) technique is used for controlling the stepping motor. Yuan-jin Yu et al. [2] developed a positioning system by producing a torque by tilting the shaft of the motor. He proposed a new approach of control by back stepping mechanism. This approach has provided a good stability in positioning of any object. Robert Konowrocki et al.[3] have worked on interaction of the belt transport system and driving stepping motor. The system consist of measuring techniques for obtaining the electrical and mechanical quantities. Electro-Mechanical model is derived for the analytical measurements. Shunming HUA et al. [7] developed a inchworm actuator for fine positioning of work piece. Here three sets of actuators are used to obtain a displacement. However the control mechanism is difficult in the proposed method. Various methods for positioning the object are developed but none of the methods use stepping motion using piezo stepping actuator. In this paper a new design for stepping mechanism using piezo electric actuator has been proposed.
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Design considerations for complex survival models

Design considerations for complex survival models

subset analysis, we analyzed overall survival after entry to the crossover phase (sur- vival after disease progression), and its association with treatment and quality of life. A total of 252 patients entered the crossover phase and have at least one QOL mea- surement, 124 patients crossed over from paclitaxel to doxorubicin (median survival is 13.0 months in this subgroup), 128 patients crossed over from doxorubicin to paclitaxel (median survival is 14.9 months in this subgroup). The data we used is quite mature, with only 2 subjects who crossed over to doxorubicin and 6 subjects who crossed over to paclitaxel were censored. We applied the Cox model with treatment effect only, the two step model incorporating the two QOL measurements, and the proposed joint model as specified in Section 2 of the paper, to analyze the treatment effect and effect of QOL. Since there are only two QOL measurements, we fit a linear mixed model. To satisfy the normality assumption for the longitudinal QOL, we transformed the observed QOL to QOL 1 2 . Results are report in Table 2.7.
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The 'look and feel' of an ebook : considerations in interface design

The 'look and feel' of an ebook : considerations in interface design

This theory was applied in the WEB Book experiment, in which the original, very plain electronic version of Chapter Five of C.J. can Rijsbergen’s “Information Retrieval” [12] was compared to a revised, scannable version of the chapter [13]. In the original version, each version of the chapter is allocated a separate web page and text is organised in a linear way so that users have to keep scrolling down until they reach the end of the chapt er. Hyperlinks are used to provide some basic functions: moving from one chapter to the next, from the table of contents to the beginning of chapters, and from citations to bibliographic references. In the revised version, the chapter was divided between ten separate web pages according to sub -headings in the original text, a chapter contents page provided links to each section, and more hyperlinks were used to aid navigation between the sections. Extra headings, coloured and sized, were inserted in the text in order to divide it into smaller, more digestible chunks, diagrams were centred, key words and phrases were coloured red to call attention to important pieces of text, and lists were indented, their numbers or bullets also coloured red [14].
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Object Design Considerations for Tangible Musical Interfaces

Object Design Considerations for Tangible Musical Interfaces

The label size, and thus the object size is constrained by the system resolution. This depends not only on the opti- cal resolution of the camera, but more significantly, on the available processing power. The lower the image resolu- tion, the bigger the objects have to be for correct recogni- tion. However, the image processing algorithm’s compu- tational cost has been observed to be approximately linear with the number of pixels. In fact, increasing the image resolution over 640 by 480 pixels would result in an un- acceptable temporal resolution, which is around 7Hz on our test system based on a 1 GHz Intel Pentium III pro- cessor. As discussed in (Costanza and Robinson, 2003), the marker size is also related to the maximum number of different objects supported by the system. We are using a marker set of 120 different symbols, which is currently sufficient, but could be easily exceeded by a larger collec- tion of objects, although it is unlikely that these would be used within a single session.
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Design considerations and performance of a PM linear actuator in a radiation environment

Design considerations and performance of a PM linear actuator in a radiation environment

force between bearing and shaft, and no wear should result. This is obviously not the case, as seen from the ceramic case. Preliminary studies indicated that the tolerances involved in the construction of the actuator driving the shaft should not allow significant radial forces. However, it is possible that a slight initial distortion of the shaft could lead under acceleration to flexing, significantly displacing the magnets, leading to increased off-axis forces. This can be addressed in a number of ways. More sophisticated modelling of the shaft may help to identify possible origins of the problem. Improved quality control, of bearings, magnet and coil alignment and shaft manufacture, may help to reduce forces and so bearing wear. It is important to design a stiff and stable shaft, without paying too high a price in increasing its mass.
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PRACTICAL CONSIDERATIONS FOR THE DESIGN OF AUTONOMOUS MOBILE ROBOTS

PRACTICAL CONSIDERATIONS FOR THE DESIGN OF AUTONOMOUS MOBILE ROBOTS

The diversity of the behaviour that the robot can exhibit is directly proportional to the complexity of the subsystems that the robot possesses and the manner in which they are interconnected. Therefore as robots become more sophisticated, their design becomes increasingly complex. To add further complication to the design process, the designer is also faced with many physical design constraints. Environmental uncertainty, adherence to physical laws and limitations in power, sensing, computing, materials and actuation technology serve to further complicate and make difficult the process of developing 'intelligent' robot machines. Considering the many challenges that engineers face in developing autonomous robots, it is surprising that few generalised design methodologies exist that guide the integrated design of mobile robots at a systems level. As a consequence, perhaps, few practical multi-functional robotic platforms are in existence. Instead researchers tend to focus on the development of robotic subsystems or on the development of mobile robots that are capable of a small number of specialised tasks.
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Ergonomic Considerations for Design of Industrial Workstation: A Review

Ergonomic Considerations for Design of Industrial Workstation: A Review

Baba Md Deros et al. (2011) this paper presents about the study on assembly line workstation design. This study was conducted on workers of automotive component manufacturer. Working postures of the workers during their ordinary work are observed and recorded. Ergonomic factors are thoroughly observed and analysed whether the workers are able to perform the given work and finally the result shows that the workplace was need to be redesign by CAD work to eliminate the awkward postures which tends to MSDs.

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Design Considerations for Liquid Crystal Contact lenses

Design Considerations for Liquid Crystal Contact lenses

There are four basic lens design modes, depending on whether the liquid crystal cavity forms a positive or negative meniscus lens, and whether the quiescent, field-off alignment configuration of the liquid crystal is vertically aligned (VAN) or planar aligned (PAN), as shown in figure 4. In each case, the lens focal power is changed by electrically reorienting the LC director to be either parallel or perpendicular to the surface, to give either a positive or negative optical change, ΔP, defined with respect to the change from the field off to field on states as shown. This is controlled by surface alignment and switching of the liquid crystal by applying an electric field across the cavity from electrodes deposited onto the opposing internal surfaces. The design choice depends upon whether a positive or negative Δ P is required; that is, whether or not the near vision correction is provided in for the field OFF or field ON states. Presbyopia always requires a positive correction Δ P for short distance vision. The lens may be considered more power efficient if designed to provide distance vision without operating voltage, as this operation mode is more likely be the lens’s more frequent setting. Using an LC with a positive dielectric anisotropy would then require its cavity within the lens to have a negative focal power. Likewise, using a LC with a negative dielectric anisotropy requires the LC layer to have a positive focal power. This occurs for the positive meniscus lens in a VAN mode with a positive Δε liquid crystal, or for the negative meniscus lens in a PAN mode with a negative Δε liquid crystal; options A and D in figure 4, respectively.
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Broad band microwave amplifier design considerations

Broad band microwave amplifier design considerations

BENEFITS of DISSIPATIVE GAIN COMPENSATION IMPROVES DESIGN ACCURACY EASES GAIN-BANDWIDTH LIMITATIONS ENSURES OUT-OF-BAND STABILITY INCREASES REVERSE ISOLATION REDUCES UNPREDICTABLE LOSSES[r]

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Design Considerations in the Development of a Modern Cavitation Tunnel

Design Considerations in the Development of a Modern Cavitation Tunnel

Speed and pressure control for the previous tunnel were limited by various factors including precision of controlling digital electronics, drive train mechanical design, and control valve sophistication. These factors have been given detailed consideration in control system design for the new facility. For the previous tunnel velocity control precision was about 0.05% of maximum speed. Replacement of the main pump motor and variable speed drive is expected to improve this to 0.01% of maximum speed. Further improvements are also expected from improved drive train design including the addition of a flywheel and double compliant couplings between the gearbox and external main pump bearing. Considerable improvements have been made in the sophistication of the pressure control system, including separate valve systems for coarse ranging and fine control and control software programmed for changing system characteristics. Due to different circuit architecture and requirements, the gas volume in the ceiling of the downstream tank required for pressure control and gas removal is 10 times greater than that of the surge tank in the previous tunnel. From these changes and enhancements, it is estimated that improvements for pressure control should approximate those for velocity. The combined effects of better pressure and velocity control should also improve the regulation of cavitation number which, involves the ratio of static and dynamic pressures.
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Design Considerations for Network Processor Operating Systems

Design Considerations for Network Processor Operating Systems

Network processors (NPs) promise a flexible, programmable packet processing infrastructure for network systems. To make full use of the capabilities of network processors, it is imperative to provide the ability to dynamically adapt to changing traffic patterns and to provide run-time support in the form of a network processor operating system. The differences to existing operating systems and the main challenges lie in the multiprocessor nature of NPs, their on-chip resources constraints, and the real-time processing re- quirements. In this paper, we explore the key design tradeoffs that need to be considered when designing a network processor oper- ating system. In particular, we explore the performance impact of (1) application analysis for partitioning, (2) network traffic charac- terization, (3) workload mapping, and (4) run-time adaptation. We present and discuss qualitative and quantitative results in the con- text of a particular application analysis and mapping framework, but the observations and conclusions are generally applicable to any run-time environment for network processors.
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Design Considerations for the High-Performance Campus LAN

Design Considerations for the High-Performance Campus LAN

QoS and class of service (CoS) features are built into all Juniper infrastructure, security, and application acceleration solutions. All Juniper Networks switches and routers run JUNOS Software, which comes standard with a full complement of QoS services. Juniper Networks EX Series Ethernet Switches, for example, support eight hardware queues per port and offer a range of policing options from best-effort delivery to enhanced delivery and assured delivery. Since the same JUNOS Software operating system is found across all Juniper router and switch solutions, the same QoS policies can be used throughout the LAN and WAN design for easy and consistent traffic management. In addition, ASICs in all Juniper solutions support QoS by processing prioritized data and minimizing CPU load.
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CONSIDERATIONS FOR NATIONAL DISABILITY INSURANCE SCHEME DESIGN:

CONSIDERATIONS FOR NATIONAL DISABILITY INSURANCE SCHEME DESIGN:

in all jurisdictions, the NDIS needs to take a specialist approach to young people with complex disability who might be at risk of RAC placement. The Inquiry report highlighted the need for the Scheme to be informed about, and prepared to engage with, current disability-specialist supported accommodation models where this is the preference of the participant, and utilise existing evidence to inform further development of changing traditional or innovative housing and support models for this group. Full Scheme design is planned to begin in mid 2016. The following report provides research evidence to inform, and further details regarding, the key implications and enablers for full National Disability Insurance Scheme design for young people with complex healthcare needs.
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Proficiency-Based Transcript DESIGN FEATURES + CONSIDERATIONS

Proficiency-Based Transcript DESIGN FEATURES + CONSIDERATIONS

documents that vary widely in design, language, and purpose, which often make it difficult for admissions professionals to decipher individual school systems, particularly non-conventional systems. Consequently, common denominators—such a class rank, Advance Placement courses, SAT scores—are often relied on during the decision-making process because they provide a fairly consistent benchmark, from student to student and school to school, for evaluating performance. With the move to a proficiency-based system of teaching, assessing, grading, and reporting, schools will be able to
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Design Considerations for RF Energy Harvesting Devices

Design Considerations for RF Energy Harvesting Devices

• Used by other harvesting technologies • Active monitoring of the operating point • Active monitoring of the operating point. Drawback[r]

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