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International audience; Abstract : Background: The thumb plays a critical role for manual tasks during the activities of daily life and the incidence of neurological or musculoskeletal disorders affecting the voluntary movements of the thumb is high in the elderly. There is currently no tool to assess repetitive motor sequencing of the thumb during ageing.Objectives: To report a novel procedure (the Click Test) assessing the effects of ageing on fast motor sequencing of the thumb.Methods : Healthy subjects (n = 252; mean age +/- SD: 49.76 +/- 19.97 years; range: 19-89 years; F/M: 151/101) were asked to perform fast repeated flexion/extension movements of the thumb using a mechanical counter.Results: Motor performances (assessed by the number of clicks during 3 time periods: 15, 30 and 45 sec), significantly decreased as a function of age for both the dominant (age effect; p< 0.0001 for 15, 30 and 45 sec) and the non-dominant hand (p

This study deals with calculation and comparison of performance parameters of three types of horizontal, vertical and mixed corrugated film fill packing, to their actual values in cooling tower of the Bisotoun power plant. Through this, performances of cooling packing are compared with each other. Also utilization of the most appropriate cooling tower in Bisotoun power plant has been investigated. In order to rich the above mentioned goals, added to describing performance of physical mechanisms in wet mechanical counter current cooling towers and Merkel's thermal theory, thermal properties of the pre-mentioned cooling packings are presented also, moreover performance parameters of the three packing are calculated and compared, then the appropriate conclusion is made. The results show that among the three packings, because of having appropriate characteristics like higher surface to volume ratio and mass transport coefficient and so on, the mixed corrugated packing has had the best performance in comparison with the other two packings and can perform acceptable in Bisotoun power plant. As, the Values of the cold water temperatures, the temperature difference between cold water and wet point temperature of the ambient and the coolness range the mixed corrugated packing is fully consistent with those gathered from the power plant's data. However, values of these parameters show considerable difference in two other packing with their counterparts in Bisotoun power plant, the water flow rate to air flow rate ratio in the mentioned packing shows a tiny difference with the actual value in the power plant which is 2.15 (1.4% increase). If this packing was used the amount of air used to cool down the water in the cooling tower which is prepared by each fan would be 521 m 3 /secs, which defers 5.4 % with that of Bisotoun, that is 551 m 3 /sec.

High-resolution human skin strain field data is presented for the shoulder joint measured using three-dimensional digital image correlation (3D-DIC). Developing mechanical counter pressure (MCP) space suits requires detailed understanding of human skin deformation at joints in order to fit and create MCP without restricting human mobility or increasing human energy expenditure. Previously, skin strain for this application has been measured for one degree of freedom joints such as the elbow and knee. Now using four stereoscopic camera pairs for 3D-DIC (8 cameras), a strain field comparison is made between various motions of the shoulder joint. This paper specifically compares shoulder abduction and flexion in the context of realizing a MCP space suit designed for planetary exploration. Methods are explained to perform 3D-DIC using multiple stereoscopic camera pairs for complex joint motions. These results are important to develop MCP space suits that allow upper-body mobility. The discussion of the results provides insight and data for designing optimal textile patterning for skin-tight space suits at multiple-degree of freedom joints.

This paper reports a technique for measuring the calibrating resistive input torque of a micro counter and gearbox assembly. The technique presented uses a hairspring (with a quantifiable output torque) to drive the input shaft to a mechanical counter and gearbox assembly in order to determine its resistive torque. The angular displacement of this spring, a parameter needed to compute the torque, is measured using a combination of a laser diode and a monolithic one-dimensional position sensitive device (PSD). This study includes the steps undertaken to develop it from a concept to functional prototype and interpretation of the results it yields. Tests show that in principle the use of a hairspring and PSD is a viable method of measuring micro-torque.

A comparison of high-resolution human skin strain field data at the elbow joint measured using three-dimensional digital image correlation (3D-DIC) is presented. Developing skin-tight space suits requires detailed understanding of human skin deformation at joints in order to fit and create mechanical counter pressure without restricting human mobility. Previously, skin strain has been measured at 1 cm2 resolution for one or two subjects to demonstrate the measurement technology. Now using 3D-DIC, skin strain is measured at 1 mm2. Methodology to take these measurements and the data analysis is explained in detail. This paper goes beyond the measurement technology and presents data from four subjects and compares skin strain fields of the elbow joint, which gives insight into patterns and differences between varying anthropometrics and other factors that affect skin strain. These results are important to develop mechanical counter pressure space suits that are sized correctly for each astronaut and do not inhibit locomotion. These results are discussed in the context of realizing a mechanical counter pressure space suit designed for planetary exploration.

A new burr-free hydro-mechanical punching is developed, which consists of mechanical half piercing and hydro counter punching. In this hydro-mechanical punching, hydrostatic pressure delays fracture initiation. Smooth holes without any burr and small fracture face in the sheared surface are archived. During development of hydro-mechanical punching, finite element simulations for mechanical half piercing and mechanical counter punching is performed, which lead the method of hydro counter punching. To verify the significance of hydro-mechanical punching, conventional punching is performed under similar conditions and relatively larger portion of fracture surface is detected in the punching hole. Despite the quality of sidewall is not good enough yet, it is possible to make the hole shaped upright, reduce the roll-over radius and minimize the fracture surface by the optimization of process parameters.

Today, in water and wastewater industry a lot of mechanical-volumetric flow meters are used for the navigation of the produced water and the data of these flow meters, due to use in a wide geographical range, is done physically and by in person presence. All this makes reading the data costly and, in some cases, due to the rugged topography, there is no possibility to get the data at a specific period. Since water and wastewater companies produce water and knowing the amount of water produced is one of the important components in short and long-term planning, the purpose of this project is obtaining the data from mechanical counter meters and sending data online over the Internet. The project challenges include the lack of electricity in the installation place of water meters, the existence of mechanical counters, and the quality of sending data to the web-based central server. The reasons to work on these flow meters are the high number of meters in the country, about 3.5 million meters, which makes the project economically justifiable, low price of mechanical-volumetric meters compared to ultrasonic and magnetic ones, domestic production of these meters, and convenience after-sales service in supplying components, and acceptable accuracy. Replacing these meters with similar ultrasonic and magnetic ones imposes a lot of costs to water and wastewater companies, which is inaccessible according to their current budgets. Conducting this project empowers water and wastewater companies in efficient use of resources, so that in this project once a sudden increase in consumption is spotted an alarm goes off in web based software, announcing the possible fractures in transmission lines and prevents water loss and other damage and also provides the ability to control and manage consumption. In this project, it is planned so that by using renewable energy sources, electricity needed for the device is supplied, and the existing infrastructure of the telecommunications is used in data transmission. Keywords: mechanical meter; readrealay sensor; ARM; RTU;and GSM microcontroller

Traffic survey was carried out to obtain data that are necessary for traffic study and evaluation. One of the most important characteristics of a traffic stream is its volume which can be defined as the number of vehicles passing through a section of a road per unit time. The road project which is approximately 75 km in length consists of a number of traversed roads, but the traffic study is focused only on the 6 major intersections. The surveys of traffic were conducted using volume count from 7am to 7pm each day because working at night is very unsafe in this area, by using an automatic traffic recorder (Trax 1 Plus) and road tube installation for collecting accurate data with manual counting for comparison. This study aims to analyze the current road traffic data collection methods - comparing both mechanical and manual mode of Traffic Survey simulation - in terms of capabilities and limitations on Nigeria roads using Ogoja (Mbok) Junction and Mfum road in Cross River State as a case study. The tendency of the mechanical counting machine to withstand nonstop24hrs-continuous counting was noted during the exercise compared to manual counting, since security at night cannot be predicted on manual. The design equivalent standard axle load (ESAL) generated from the result shows that Ikom-Cameroon Junction has the highest value with a difference of (0.999x10^ 6 ) between the mechanical and manual, this value shows a downward effect using manual data for the pavement structural thickness evaluation, this can further degenerate to the structural failure at the earlier stage, tensional fatigue, cracks etc. However, traffic study for the period 2015 to 2035 was considered in the analysis, the equivalent standard axle load (ESAL) generated along the section of the corridor and the pavement thickness shows that automatic counter machine is more accurate than the manual. Nonetheless the mechanical counter is more advantageous compared to the manual counter to this reasons the mechanical counter should therefore be employed during the raw data traffic survey. Manual on the other hand less useful for traffic survey in predicting the feature traffic analysis. http://dx.doi.org/10.4314/njt.v35i2.1

One method of determining particle energies in nuclear research depends upon the measurement of pulses produced by the particles in an ionization chamber. The Pulse Analyser is an instrument which analyses the electrical pulses from the chamber into a number of classes according to their amplitude and hence produces an energy spectrum of the particles. It has the following features: (1) every pulse is counted ensuring the highest accuracy for a given time; (2) some indication of the final result appears while the experiment is in progress; (3) the number of pulses within a certain amplitude range is recorded by a mechanical counter, eliminating most of the labor required for obtaining results. Problems of design are discussed, and a brief survey of the ways in which they are treated in five different Pulse Analysers is given. One of these instruments, built by the authors, is described in detail. This Analyser is designed for slowly rising pulses (up to 1 millisecond in duration) and for low counting rates (up to a few hundred per minute). It has 20 identical channels, each channel recording the pulses within an amplitude range that can be varied from 0.1 to 10 volts. The performance of the Analyser is discussed and some typical results obtained with it are given.

Human explorers of planetary surfaces would benefit greatly from a spacesuit design that facilitates locomotion. To aid in the development of such an extravehicular activity suit, a design effort incorporating the concept of mechanical counter pressure (MCP) was undertaken. Three-dimensional laser scanning of the human body was used to identify the main effects of knee flexion angle on the size and shape of the leg. This laser scanning quantified the changes in shape that must be supported by an MCP garment and the tension that must be developed to produce even MCP. Evaluation of a hybrid-MCP concept using inextensible materials demonstrated strong agreement between experimental data and a mathematical model with rigid cylinder geometry. Testing of a form-fitting garment on the right lower leg of a subject demonstrated successful pressure production. Further research is required to evaluate how evenly pressure can be distributed using the hybrid-MCP concept.

A scaler unit is described which has been designed for counting pulses from Geiger-M?ller counters or ionization chambers in a decimal system. The unit consists of two electronic scales-of-ten with either neon lamp or meter indication, followed by a mechanical counter. The resolving time of the scaler can be made as low as 3 ?sec. and the unit is capable of recording counting rates up to 1000 per sec. It is built on a standard G.P.O. panel, suitable for rack or bench mounting.

X‐ray diffraction spots on films vary in area and are uneven in density. An instrument is described, which, after calibration against a standard intensity scale imprinted on the film, scans the spot by a light ray, and transforms transmitted light pulses into linear functions of intensity by electronic means. A figure, proportional to the intensity of the spot, is obtained on a mechanical counter. The integrating process is fully automatic, and measurement of one spot takes about a minute. Reproducibility depends on the relative intensity of the measured spot, and can be raised up to 1 percent.

A variety of standard hardware has been developed to link the Sigma 2 control computer to the Indiana University cyclotron. Monitoring of analog signals is accomplished by using dual ramp, integrating analog to digital converters of the 11 bit or 14 bit variety. Up to 16 channels may be multiplexed to each converter. The control of power supplies is accomplished by using 12 bit or 16 bit digital to analog converters, which may be optically isolated if required, or by motor-driven potentiometers. Movement of probes or slit assemblies is accomplished via stepping motors with feedback obtained from a mechanical counter with electrical readouts or from potentiometers. A standard on/off circuit has been developed which is applicable to power supplies as well as to solenoid operated devices such as beam stops and valves.

A PHOTO-ELECTRIC apparatus for counting individual microscopic cells in fluid suspension has been constructed in this laboratory. A sufficiently large signal-to-noise ratio from a single cell or a part of it has been obtained by the use of a specially designed dark-field system and an RCA 931-A multiplier phototube. The phototube is followed by an amplifier which operates a mechanical counter. As it was not possible to arrange the cells in one line in a capillary space, a scanning method using an ordinary counting chamber was evolved.

United States. National Aeronautics and Space Administration (OCT Space Technology Research Fellowship Grant NNX11AM62H)

A simple large range digital readout micromanometer has been designed and fabricated. The innovative feature is a suitable gear train which transmits the rotational motion of the lead screw to a 5‐digit reversible mechanical counter. The digital readout makes the data collection easier, convenient, and less liable to reading errors.

The counter uses a loud-speaker movement in conjunction with a stop-watch mechanism. It has a greater resolving power than a telephone call counter, and its lower inductance makes it very suitable for operation from a thyratron.

A new spectrometric mount particularly applicable to the region 20–500 A has been developed. Working at grazing incidence, the actual angle may be varied from around 80 to 88° to permit optimizing the compromise between the lowest wavelength detectable (which decreases with increasing angle of incidence) and optical abberations (which increase with increasing angle). Whatever angle is set, readout is linear in angstroms and readings appear directly on a mechanical counter. The mount is convertible for spectrographic use and, with some modifications, may be used as a monochromator in which both entrance and exit slits are accessible from outside of the vacuum.