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El proyecto consiste en dimensionar diferentes estructuras de pavimento flexible adaptando la metodología mecanístico-empírica a la práctica actual de diseño de pavimentos en Colombia, para poder determinar los módulos que están desarrollando los materiales granulares de base y sub-base en estas estructuras y a la vez establecer factores camión (factores de daño) para las estructuras evaluadas, que permitan establecer recomendaciones para garantizar que los diseños que se están realizando con metodologías convencionales sean más conservadores y consecuentes con el estado actual del conocimiento. The project consists of sizing different flexible pavement structures adapting the mechanistic-empirical methodology to the current practice of pavement design in Colombia, in order to determine the modules that are developing the granular base and sub-base materials in these structures and at the same time establish truck factors (damage factors) for the structures evaluated, which allow establishing recommendations to ensure that the designs that are being carried out with conventional methodologies are more conservative and consistent with the current state of knowledge. Ingeniero Civil Pregrado

Noise and whole-body vibration measurements were made in a Viking military vehicle to determine the variation that should be expected during repeat measures, the effect of speed (up to 60 km/h in 5 km/h increments), and during travel over different types of terrain (comprising concrete road, gravel track and rough cross-country). Measurements were made at various crew positions (including the driver and commander) in both the front and the rear cabs in the vehicles. Three translational axes of vibration were measured in each seat. Two speeds were investigated over road (35 km/h and 55–60 km/h) and gravel (20 km/h and 35 km/h) surfaces. The effect of varying speed of the vehicle on the measured noise and vibration magnitudes was also investigated. The highest sound pressure level (LAeq) of 104 dB(A) was measured at the commander’s standing position during travel over concrete road at 55 km/h. Higher noise levels occurred for a standing commander compared with when sitting on the seat. A maximum single axis frequency-weighted vibration magnitude of 1.0 m/s2 r.m.s. was measured on the driver’s seat during travel over track at 35 km/h. Higher vibration magnitudes occurred during travel over track compared with travel over road. Both noise and vibration exposure of crew within the Viking vehicle increased with increasing speed of the vehicle.

With solar tracking, it will become possible to generate more energy since the solar panel can maintain a perpendicular profile to the rays of the sun. Even though the initial cost of setting up the tracking system is considerably high, there are cheaper options that have been proposed over time. This research discuss the design and construction of a prototype for a solar tracking system that has a single axis of freedom. Light Dependent Resistors (LDRs) are used for sunlight detection. The control circuit is based on an ATMega328P microcontroller. It was programmed to detect sunlight via the LDRs before actuating the servo to position the solar panel. The solar panel is positioned where it is able to receive maximum light. As compared to other motors, the servo motors are able to maintain their torque at high speed. They are also more efficient with efficiencies in the range of 80-90%. Servos can supply roughly twice their rated torque for short periods. Through tracking, there will be increased exposure of the panel to the sun, making it have increased power output. The trackers can either be dual or single axis trackers. As a single tracking system is cheaper, less complex, and still achieves the required efficiency, so it was used.

The main problem in studying the feasibility of solar systems is the enormous gap between theory and experimental radiation intensity, so to get accurate results there is a need for studying energy production in the site of the system empirically. In this study, the energy production of both fixed PV panel system and the system with single-axis tracking were empirically evaluated in Medina, Saudi Arabia. The two systems had the same 270 Wp PV panel. The fixed system was tilted by 23.5 degrees, and the single-axis tracker was tilted by 26 degrees. Both systems had an azimuth angle of zero degrees. A closedloop three-points controller was used to control the tracker with 120 degrees rotation range. The two systems operated simultaneously in July, and the data were collected for 14 days. The empirical results showed that the tracker increased the generated energy by 48.5% during the testing period. As a comparing method, a modified ASHRAE model was used to estimate the increase in the panel's energy output with and without the single-axis tracker, and RMSE and MBE were calculated. It's been found that the experimental energy generation is 10%, 5% less than the estimation of the modified model for the fixed system and the tracking system, respectively. Finally, based on the analysis, it's been estimated that the singleaxis tracker will increase the generated energy by 22.5% yearly in Medina.

The article examines existing works considering the process of tearing of flax fibre, specifically fibrous matrix and linkages within it. In particular authors point out the necessity of taking into account the destruction of individual fibres during deformation and tearing process. The end result of this analysis is a multipart mechanical model allowing for various effects that may take place during the said process. This model is implemented in software and used to model the behaviour of several strands of fibre of varying quality. The results match the observed behaviour of actual samples with similar properties, which allows using the model presented to estimate the effect various properties of flax fibre have on its tensile strength.

Although some authors realized various measurement techniques and relevant standards in the experimental verification, the existing contributions still did not mention more complex automated workplaces with industrial robotic arm participation. To solve this, we provide a different view of the interconnection between individual devices (positioner, robot, etc.) controlled by third-party methods (Siemens products). Also, to obtain the necessary effectiveness, we tested and verified selected accuracy parameters for the participating device component (positioner). The proposed work tries to fulfill expectations for a precise welding technology (to ensure simultaneous movements of both the industrial robotic arm and positioner) to achieve higher quality and productivity. However, the components are from different manufacturers.

In this paper, a novel evacuated tube solar collector (ETSC) is first designed and built. Then, the impact of adding reflector, reflector plus single-axis sun tracker and reflector plus two-axis su...

Five-axis machining plays an important role in manufacturing by dint of its high efficiency and accuracy. While two rotation axes benefit the flexibility of machining, it also brings limitations and challenges. In order to further balance machining precision and efficiency, an improved feedrate scheduling method is presented considering geometric error and kinematic constraints for the Non Uniform Rational B-Spline (NURBS) interpolation in five-axis machining. A simplification method is proposed to calculate the geometric error which describes the deviation between the ideal tool path and the real tool path induced by the non-linear movement. A linear relation between geometric error and feedrate is built to limit the feedrate. The constraints determined by single axis kinematic performance and tangential kinematic performance are also considered. Under these constraints, a constrained feedrate profile is determined. Aiming to get more constant feedrate in the difficult-to-machine areas, this work proposes a scheduling method which combines morphological filtering and S-shape acceleration/deceleration (acc/dec) mode. Simulations and experiments are performed to compare the proposed feedrate scheduling method with two previous feedrate scheduling method and the results prove that the proposed feedrate scheduling method is reliable and effective.

The algorithm of the turn of the spacecraft from an initial arbitrary angular position at an arbitrary angular rate to a solar-oriented attitude is investigated. Minimum essential equipment of the motion control system required for the purpose of ensuring maintenance of solar orientation is defined: a solar sensor, a single-axis angular-rate sensor, low-thrust liquid rocket engines. A solution of the problem of defining the spacecraft angular rate vector by the measurements of the deviation of the optical axis of the solar sensor from the sun vector and the single-axis angular-rate sensor is presented. The conditions under which control action on the rocket engines for the purpose of changing the value of the angular-rate vector for the Sun to get into the field of viewing of the solar sensor or for the spacecraft stabilization are defined. Mathematical modeling of the spacecraft attitude control system with the unknown initial state vector of motion is carried out. The results of mathematical modeling confirmed the efficiency of the proposed algorithm in terms of reducing propellant fuel consumption and high-speed performance. In comparison with the known methods of solving the problem of reducing angular speed (a lengthy process with the use of a magnetic system or a fast process with the use of a three-axis angular-rate sensor and rocket engines) the duration of the process of reducing angular speeds is the same as in normal operation, however, at the same time the problem of bringing spacecraft into the solar oriented attitude is solved.

This is an experimental study. As current posterior-substituting (PS) total knee arthroplasties have been reported to incompletely restore intrinsic joint biomechanics of the healthy knee, the recently designed single axis radius PS knee system was introduced to increase posterior femoral translation and promote ligament isometry. As there is a paucity of data available regarding its ability to replicate healthy knee biomechanics, this study aimed to assess joint and articular contact kinematics as well as ligament isometry of the contemporary single axis radius PS knee system. Implant kinematics were measured from 11 cadaveric knees using an in vitro robotic testing system. In addition, medial collateral ligament (MCL) and lateral collateral ligament (LCL) forces were quantified under simulated functional loads during knee flexion for the contemporary PS knee system. Posterior femoral translation between the intact knee and the single axis radius PS knee system differed significantly (p

Process monitoring and in-process control in milling requires reliable sensor data from rotating tooling systems. Vibration sensing by an instrumented tool holder close to the cutting zone has been proven useful in mitigating chatter. A model is presented that enables the interpretation of vibration data of the rotating sensor and tool system to identify edge chipping. Thus, data from a single axis accelerometer can be interpreted to identify the existence of edge chipping on one of multiple cutting edges. The classification of observed effects is derived from methods developed for machine learning, which is demonstrated and evaluated by experimental results.

With over 30 million people worldwide requiring assistive devices, there is a great need for low-cost and high-performance prosthetic technologies that can enable kinematics close to able-bodied gait. Low-income users of prosthetic knees in the developing world repeatedly report the need for n inconspicuous gait to mitigate the severe socioeconomic discrimination associated with disability. However, passive prosthetic knees designed for these users have primarily focused on stability and affordability, often at the cost of the high biomechanical performance that is required to replicate able-bodied kinematics. In this study, we present the design and preliminary testing of two distinct mechanism modules that are novel for passive prosthetic knee applications: the stability module and the damping module. These mechanisms are designed to enable users of single-axis, passive prosthetic knees to walk with close to able-bodied kinematics on level-ground, specifically during the transition from the stance phase to the swing phase of the gait cycle. The stability module was implemented with a latch mounted on a virtual axis of a four-bar linkage, which can be engaged during early stance for stability and disengaged during late stance to initiate knee flexion. The damping module was implemented with a concentric stack of stationary and rotating pairs of plates that shear thin films of high-viscosity silicone oil. The goal of the resulting first-order damping torque was to achieve smooth flexion of the prosthetic knee within the able-bodied gait range (64 ± 6 deg). For preliminary user-centric validation, a prototype prosthetic knee with the stability module and two different dampers (with varying damping coefficients) was tested on a single subject with above-knee amputation in India. The stability module enabled smooth transition from stance to swing with timely initiation of knee flexion. The dampers also performed satisfactorily, as the increase in the damping coefficient was found to decrease the peak knee flexion angle during swing. The applications of the mechanisms presented in this article could significantly improve the kinematic performance of low-cost, passive prosthetic knees.

In the past decade, flexible physical sensors have attracted great attention due to their wide applications in many emerging areas including health-monitoring, human-machine interfaces, smart robots, and entertainment. However, conventional sensors are typically designed to respond to a specific stimulus or a deformation along only one single axis, while directional tracking and accurate monitoring of complex multi-axis stimuli is more critical in practical applications. Multidimensional sensors with distinguishable signals for simultaneous detection of complex postures and movements in multiple directions are highly demanded for the development of wearable electronics. Recently, many efforts have been devoted to the design and fabrication of multidimensional sensors that are capable of distinguishing stimuli from different directions accurately. Benefiting from their unique decoupling mechanisms, anisotropic architectures have been proved to be promising structures for multidimensional sensing. This review summarizes the present state and advances of the design and preparation strategies for fabricating multidimensional sensors based on anisotropic conducting networks. The fabrication strategies of different anisotropic structures, the working mechanism of various types of multidimensional sensing and their corresponding unique applications are presented and discussed. The potential challenges faced by multidimensional sensors are revealed to provide an insightful outlook for the future development.

This contribution reports on a yearlong spectral albedo measurement campaign performed in Roskilde, Denmark. Four albedo scenarios are monitored using three sensor types. The ground surfaces include green grass, dry grass, gravel, and snow – all of which have been monitored with albedometers based on spectroradiometers, silicon-pyranometers, and thermopile pyranometers. Implications of using the various albedo data sources/assumptions in bifacial PV modeling are assessed with the spectrally weighted bifacial energy gain (BEG). We find that BEG differs by as much as 3% using the three albedo sensors and can deviate by 7% from the ground truth when an incorrect static spectral albedo assumption is used. Finally, the spectral mismatch factor (SMM) is calculated to summarize rear plane of array (POA) spectral shifts. Our measurements show midday backside POA spectral shifts as high as 25% for Silicon bifacial PV devices mounted on single axis trackers above grass.

This paper describes a single axis MEMS accelerometer with the wide detection range of acceleration from micro-G level to 20 G $(\mathrm{G}=9.8\ \mathrm{m}/\mathrm{s}^{2})$ . We propose the MEMS accelerometer with two proof masses on a single chip of $4 \times 4\ \text{mm}^{2}$ in area. One proof mass is for over micro-G level sensing and the other is for below 20 G sensing. The experimental results of the fabricated device show that the Brownian noise $B_{\mathrm{N}}$ and the sensitivity $S$ of the proof mass for over micro-G level are $0.18 \mu \mathrm{G}/\sqrt{\text{Hz}}$ and 5.0 pF/G, respectively and these of it for below 20 G are $0.81 \mu \mathrm{G}/\sqrt{\text{Hz}}$ and $3.7 \times 10^{-2}\ \text{pF}/\mathrm{G}$ , respectively. It is confirmed that the proposed device could realize the wide detection range of acceleration from micro-G level to 20 G. (130)

Las sondas magneticas (tambien conocidas como bobinas de punto B) son dispositivos electromagneticos utilizados para medir la variacion del campo magnetico en muchos rangos de frecuencia. La frecuencia del campo magnetico a medir se relaciona directamente con el metodo elegido para realizar la calibracion de la bobina de punto B. Este trabajo presenta una calibracion de bobina de punto B en un rango de frecuencia de 6.16 kHz a 36.63 kHz. Un inductor L (bobina de Helmholtz) se conecta en paralelo con un banco de condensadores variable C var para formar un circuito resonante LC var acoplado. El circuito LC var se alimenta con un oscilador de medio puente. La capacidad C var varia hasta que el circuito se encuentra en estado resonante a diferentes frecuencias. El circuito resonante produce oscilaciones sinusoidales en la frecuencia de banda mencionada. La sensibilidad se calcula utilizando el voltaje V out de la bobina de punto B y el voltaje V H medido desde las terminales de Helmholtz

This work presents a study in the theoretical and experimental performance of PV cells and tracking surfaces using the isotropic and anisotropic (HDKR) models’ simulations for single and dual axis ...

Background/Objectives: The objectives of this study are as follows: • To throw light on the concepts of economic empowerment of women. • To know the reality of the economic empowerment of women in Al-Kamil Governorate and the obstacles it faces. • Providing practical recommendations based on the results of the study supports the vision and direction of the Kingdom of 2030 in terms of achieving the highest rates of economic sustainability. Methods/Statistical Analysis: Depends on the use of statistical analysis methods to identify and analyze the levels of economic empowerment of women in Al-Kamil Governorate. To achieve the above objectives, the present study is based on the following main hypothesis test: There are still obstacles to the economic empowerment of women in the province of Kamel. In this study, we relied on the use of descriptive and analytical descriptive methods to achieve research objectives. The required data were obtained by designing a questionnaire that represents the main source of data as it was distributed to the study population. This questionnaire consists of a single axis consisting of 15 paragraphs. Findings: Two of main findings of this study can be illustrated in the following points: • The results showed that there are obstacles to the economic empowerment of women in Al-Kamil Governorate. In contrast, there is a difference of views regarding the identification of obstacles and challenges facing women’s economic empowerment. • Based on the results of the analysis, women are still facing difficulties in accessing resources and do not have control over them, which impedes their economic empowerment. Women’s ownership of resources is necessary to achieve their economic empowerment. Improvements/Applications: Reflect the reality of the economic empowerment of women in the study community and the measures that must be taken to enhance the empowerment of women in the governorate. Keywords: Al Kamil Governorate, Empowering, Labor and SPSS

The main importance for this paper is that sixth year students can be used laptop and projector in presentation for their mini thesis though the light is off. As four 90W solar panel is connected in parallel, total power is 360W that is reliable for our loads. In this paper, the comparison between single axis and dual axis tracker radiation for Pyay District is expressed. Moreover, Ardunio program is applied for dual axis solar tracker. Myanmar is more suitable solar power to store energy in battery during sunny days as renewable. Dr. Zarchi San | Daw Pan Wint Hmone Htwe | Daw Kkhaing Wint "Solar Tracker in P.T.U E.P Department" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-3 , April 2019, URL: https://www.ijtsrd.com/papers/ijtsrd23468.pdf

The performance of solar photovoltaic systems can be improved if solar modules are kept perpendicular to the direction of solar radiation. Therefore, an accurate solar tracker system is important to continuously orientate solar modules to be always perpendicular to the solar radiation throughout the day. This paper presents the development and testing of a selfadjusting single-axis solar tracking system using two photovoltaic cells as photosensors. A prototype of the single-axis solar tracking system is built and tested based on continuous tracking method to the sun’s position throughout the day. An Arduino UNO microcontroller, a servo motor, and photovoltaic cells are selected as the components of the prototype. As this is an active tracking system, the orientation of the tracker receiver surface depends on the feedback received from the photosensors. Outdoor tests were carried out under clear skies at Kota Damansara, Malaysia (3.1467512 N, 101.5740615 E). The tracking inaccuracy is less than 5% with the maximum being 4.12%.

This work examined the effects of burst or pulsed flows on the cleaning of tank surfaces soiled by egg yolk, under alkaline conditions, using a single axis rotary spray head. Firstly, four cleaning approaches (continuous flow without pre-wetting, continuous flow with pre-wetting, pulsed flow with a shorter period, pulsed flow with a longer period) were tested on a pilot-scale tank to clean both uncooked and cooked fouling materials. The effects of temperature, flow rate and alkali concentration were investigated. The results show that pulsed flows improve cleaning behavior, where pulsing with a shorter period and higher frequency results in the most deposit removal at the same detergent consumption. The impact of pre-wetting is less significant under the investigated conditions. Some findings are consistent with earlier reports, stating that higher temperature and flow rate improve cleaning by reducing cleaning time. An optimal alkali concentration exists, which is in line with results reported by other researchers when investigating other protein soil types. The economic benefits by using pulsed flow cleaning were discussed. Then, scale-up tests confirmed that the enhancement of cleaning by using pulsed flow with short period and high frequency could also apply in an industry-scale tank.

This paper presents the mechanical design of a single axis solar tracking system, as well as the electronic design of a system that to record in real time the electric power delivered by the solar tracker and to evaluate its performance. The interface was developed in Labview and it compares the power supplied by the tracker with the power supplied by static solar panel of the same characteristics. The performance is initially simulated using Pv-Syst software, and later validated with the data obtained by the interface. As a result, the use of the solar tracker increases the power delivered by a minimum of 19%, and it can go as high as 47.84%, with an average in increase in power of 19.5% in the monthly energy production. This experimental result was compared with the simulation by Pv-Syst software and shows a difference of only 2.5%, thus validating the reliability of the simulation. This behavior pattern coincides with previous studies carried out for equatorial latitudes. Este artículo presenta el diseño mecánico de un seguimiento solar de un solo eje. sistema, así como el diseño electrónico de un sistema que grabar en tiempo real la potencia eléctrica entregada por el seguidor solar y evaluar su actuación. La interfaz fue desarrollada en Labview y compara el energía suministrada por el seguidor con la energía suministrada por el panel solar estático de las mismas características. El rendimiento se simula inicialmente con Pv-Syst software, y posteriormente validado con los datos obtenidos por la interfaz. Como un Como resultado, el uso del seguidor solar aumenta la potencia entregada por un mínimo del 19%, y puede llegar hasta el 47,84%, con un promedio en aumento de potencia del 19,5% en la producción de energía mensual. Esto El resultado experimental se comparó con la simulación del software Pv-Syst. y muestra una diferencia de solo 2.5%, validando así la confiabilidad del simulación. Este patrón de comportamiento coincide con estudios previos realizados para latitudes ecuatoriales.

This work examined predictions of the interpolation of familiar views (IFV) account of object recognition performance in 5-month-olds. Infants were familiarized to an object either from a single viewpoint or from multiple viewpoints varying in rotation around a single axis. Object recognition was then tested in both conditions with the same object rotated around a novel axis. Infants in the multiple-views condition recognized the object, whereas infants in the single-view condition provided no evidence for recognition. Under the same 2 familiarization conditions, infants in a 2nd experiment treated as novel an object that differed in only 1 component from the familiar object. Infants' object recognition is enhanced by experience with multiple views, even when that experience is around an orthogonal axis of rotation, and infants are sensitive to even subtle shape differences between components of similar objects. In general, infants' performance does not accord with the predictions of the IFV model of object recognition. These findings motivate the extension of future research and theory beyond the limits of strictly interpolative mechanisms.

The kinematics of human knee joint mainly includes the all degree of freedom motion of human knee joint. The human knee joint is the most complex structure of human anatomy and thus it also has high risk of failure. This joint may fail due to failure in ligaments, bone or any other component of the knee joint. Thus, the motion can be restored through the application of prosthetic knee joint. By comparing various single axis and polycentric prosthetic knee designs on the basis of maximum stress induced, manoeuvrability, weight and an optimal model could be developed that will not only have lightweight but will also include easy and low-cost manufacturing. Simulation-based finite element analysis was done on a single axis and two polycentric knee prosthetic knee designs using ANSYS WORKBENCH 18.1.

In one experiment we examined the organizational structure of spatial memories for familiar environments, comparing it directly with that for unfamiliar environments. Participants in the familiar condition pointed from imagined perspectives towards objects in their own rooms and their performance was compared to that of matched controls in an unfamiliar condition who carried out the same task after studying the same rooms in immersive Virtual Reality. In both conditions, participants were faster and more accurate in pointing from imagined perspectives that were aligned with the geometry of the room (vs. not aligned), suggesting the presence of orientation-dependent representations. Whereas in the unfamiliar condition pointing performance was best along a single axis, performance in the familiar condition was about equal across all 4 orientations that were aligned with the geometric structure of the room. Moreover, performance in the familiar condition was influenced by the orientation from which participants started to preview the room prior to testing; in contrast, in the unfamiliar condition performance was not influenced by the orientation from which encoding started. This finding suggests that post-encoding situational factors (e.g., the starting orientation from which an environment is previewed) can prime the accessibility of information in well-established long-term spatial memories.

Research shows that Black and Latinx legislators make a difference in the welfare policies states enact. Do women also make a distinctive contribution? Focusing on state welfare reform in the mid-1990s, Chapter 6 weighs the efficacy of two alternative approaches to answering that question. An additive approach, which treats gender and race/ethnicity as mutually exclusive, suggests that female legislators—regardless of race/ethnicity—will mitigate the more restrictive and punitive aspects of welfare reform, much like their Black and Latinx counterparts do. In contrast, an intersectional approach, which emphasizes the interdependence of gender and race/ethnicity, suggests that legislative women of color will have the strongest countervailing effect on state welfare reform—stronger than that of other women or men of color. The analysis demonstrates that an intersectional approach yields a better understanding of race, gender, and representation: legislative women of color have a distinctive impact on welfare policy in the states.

The purpose of designing a spacecraft Altitude and dynamic control models play an important role in an interplanetary space mission. Particular emphasis is controlling spacecraft Altitude by sail tilting and shifting. In addition, investigate an uncertain balance amongst the centre of pressure and centre of mass on a single axis gimbaled control. Implies a method of Monte Carlo is with standing a significant of solar pressure disturbance torque in deep space mission. A flight test experiment drives in a Low Earth Orbit (LEO), hence, authenticate the source of solar sailing is also suggested. Parameters are incorporating to study and demonstrate the various principals and methods involved in altitude control design and dynamic modeling at LEO. Mitigation of disturbance torques was also examined.

This paper studies the optimization of control parameters for single-axis attitude control of a rigid satellite using thrusters. It is desired to tune the control parameters to minimize the number of thruster firings. The motion task is defined as an attitude pointing maneuver from arbitrary initial condition to the rest. To this end, a control loop with pulse-width pulse-frequency modulator is suggested. The control actuators are pairs of identical non-ideal thrusters which each one produces torque in one direction around the control axis. A novel approach is proposed to model the dynamics of thruster with a design parameter which shapes the response of the actuator. Nine parameters of the control loop, e.g. feedback gains, modulator parameters, and thruster dynamics, are selected as decision variables. Genetic algorithm is used to find the optimal values of the variables such that the firing is minimized. It is shown that firing minimization requires a sluggish thruster. Moreover, to study the effect of deviation from optimal value on number of thruster firings and fuel consumption, a sensitivity analysis is performed. Based on sensitivity analysis, an optimal range is suggested for each parameter where both number of firing and fuel consumption are minimized.

A low cost DC power data logger was designed. It could log data about generated solar energy from two solar systems. The power was measured indirectly. Calculation of power and energy was made every 255 ms. They were averaged and logged with interval one minute. The data logger was made in order to analyze the operation of different solar systems types: fixed mount vs. single axis, single axis vs. double axis, solar system with PWM vs. system with MPPT controller.

Objectives Microelectrode arrays offer a means to probe the functional circuitry of the brain and the promise of cortical neuroprosthesis for individuals suffering from paralysis or limb loss. These devices are typically comprised of one or more shanks incorporating microelectrode sites, where the shanks are positioned by inserting the devices along a straight path that is normal to the brain surface. The lack of consistent long-term chronic recording technology has driven interest in novel probe design and approaches that go beyond the standard insertion approach that is limited to a single velocity or axis. This review offers a description of typical approaches and associated limitations and surveys emergent methods for implantation of microelectrode arrays, in particular those new approaches that leverage embedded microactuators and extend the insertion direction beyond a single axis. Materials and methods This review paper surveys the current technologies that enable probe implantation, repositioning, and the capability to record/stimulate from a tissue volume. A comprehensive literature search was performed using PubMed, Web of Science, and Google Scholar. Results There has been substantial innovation in the development of microscale and embedded technology that enables probe repositioning to maintain quality recordings in the brain. Innovations in material science have resulted in novel strategies for deployable structures that can record from or stimulate a tissue volume. Moreover, new developments involving magnetically steerable catheters and needles offer an alternative approach to "pull" rather than "push" a probe into the tissue. Conclusion We envision the emergence of a new generation of probes and insertion methodologies for neuromodulation applications that enable reliable chronic performance from devices that can be positioned virtually anywhere in the brain.

Many researchers and authors recommend against dual axis charts, yet the feature is common in financial timeseries analysis. We provide a case study where dual axis timeseries charts are are necessary for fine grain correlation analysis otherwise not observable using single axis charts, normalization charts, scatterplots nor statistical correlation analysis. Further, we show dual axis charts occur in 19% of financial timeseries charts indicating common use.

Previous studies demonstrated distinct neural correlates underpinning impaired self-regulation (dysregulation) between individuals with autism spectrum disorder (ASD) and typically developing controls (TDC). However, the impacts of dysregulation on white matter (WM) microstructural property in ASD and TDC remain unclear. Diffusion spectrum imaging was acquired in 59 ASD and 62 TDC boys. We investigated the relationship between participants’ dysregulation levels and microstructural property of 76 WM tracts in a multivariate analysis (canonical correlation analysis), across diagnostic groups. A single mode of brain-behavior co-variation was identified: participants were spread along a single axis linking diagnosis, dysregulation, diagnosis-by-dysregulation interaction, and intelligence to a specific WM property pattern. This mode corresponds to diagnosis-distinct correlates underpinning dysregulation, which showed higher generalized fractional anisotropy (GFA) associated with less dysregulation in ASD but greater dysregulation in TDC, in the tracts connecting limbic and emotion regulation systems. Moreover, higher GFA of the tracts implicated in memory, attention, sensorimotor processing, and perception associated with less dysregulation in TDC but worse dysregulation in ASD. No shared WM correlates of dysregulation between ASD and TDC were identified. Corresponding to previous studies, we demonstrated that ASD and TDC have broad distinct white matter microstructural property underpinning self-regulation.

This paper proposes a mathematical method to calculate unbalanced condition for single axis air bearing table (SAABT). When SAABT is unbalanced, it will move like a pendulum. According to the motion of the pendulum, the mathematic model of SAABT system is built and the unbalanced torque size can be derived. Due to the unbalanced torque size is confirmed, the balance can be adjusted by putting corresponding size mass block on the load plate. At last, the specific steps about adjusting balance are list and the way above is verified by experiments. This method of adjusting balance has lots advantages, such as simple operation and high efficiency.

The quest to increase the energy yield of solar PV farms has led to extensive research on bifacial modules and tracking systems. Previous studies have shown ~12% increase in power for single-axis tracking of standalone bifacial PV modules, but the corresponding gain for bifacial solar farms remains unknown. In this paper, we demonstrate the modeling and physics of single-axis tracking bifacial PV farms that include the essential aspect of mutual shading between the rows of PV panels. Our results show that single-axis tracking bifacial farms outperform fixed mono/bifacial for locations and times with higher direct light fraction. The worldwide maps show a range of yearly power gain from 10-20% for latitudes > 40°. Overall, a judicious deployment of single-axis tracking bifacial solar PV farms would offer immense potential in energy yield maximization and eventual LCOE minimization.