High Speed In Order Research Articles

In-Depth Analysis of Unmodulated Visible Light Positioning Using the Iterated Extended Kalman Filter.

Indoor positioning with visible light has become increasingly important in recent years. Usually, light sources are modulated at high speeds in order to wirelessly transmit data from the fixtures to a receiver. The accuracy of such systems can range from a few decimeters to a few centimeters. However, additional modulation hardware is required for every light source, thereby increasing cost and system complexity. This paper investigates the use of unmodulated light for indoor positioning. Contrary to previous work, a Kalman filter is used instead of a particle filter to decrease the computational load. As a result, the update rate of position estimation can be higher. Additionally, more resources could be made available for other tasks (e.g., path planning for autonomous robots). We evaluated the performance of our proposed approach through simulations and experiments. The accuracy depends on a number of parameters, but is generally lower than 0.5 m. Moreover, temporary occlusion of the receiver can be compensated in most cases.

Research on tribological characteristics of bevel gear after shot blasting based on 85-pellets model

High-speed overloading puts forward very strict requirements on the bending strength of spiral bevel gears, and shot blasting is a technological process method to increase gear bending fatigue strength significantly. During the process of shot blasting, a large number of tiny pellets bombard metal target material surface at very high speed in order to let the target material form plastic deformation and form strengthened layer at the same time. As the bombarded target, the microstructure of gear surface spiral bevel gear is inevitably changed. This paper aims at revealing how the shot peened surface microstructure of the spiral bevel gear affects lubrication of gear and establishes a reasonable microstructure description model of the shot blasting surface of the spiral bevel gear, revealing the tribological characteristics of spiral bevel gears after shot blasting treatment based on the elastohydrodynamic lubrication theory. Also, comparative research is carried out on a variety of lubrication characteristics of the microstructure surface.

Prevalence of Hepatitis B and C Viral Infection Among Pregnant Women in Peshawar, Pakistan.

BackgroundViral hepatitis during pregnancy is associated with a high risk of maternal complications. The virus has a high risk of vertical transmission and it has been reported as the leading cause of maternal death.ObjectivesTo study the prevalence of hepatitis B (HBV) and hepatitis C (HCV) viral infections among pregnant women in the Peshawar district of Pakistan.Materials and MethodsThe cross-sectional study took place between July 2013 and April 2014. A total of 10,288 samples were collected from pregnant women living in different areas of the Peshawar district. The samples were centrifuged at a high speed in order to obtain a clear supernatant serum. All samples were screened for HBV and HCV using the immunochromatographic technique.ResultsThe overall prevalence of HBV was found to be 1.16%, although it varied throughout the study period. The highest prevalence of HBV (1.69%) was observed during January 2014. The overall prevalence of HCV infection among the pregnant women was observed to be 1.42%. The highest prevalence of HCV infection (2.22%) was found during March 2014.ConclusionsThe overall prevalence of HBV and HCV was 1.16% and 1.42%, respectively. The incidence of HCV infection among the pregnant women was higher than that of HBV infection.

Expression pattern of potential biomarker genes related to growth, ion regulation and stress in response to ammonia exposure, food deprivation and exercise in common carp (Cyprinus carpio)

Waterborne ammonia has become a persistent pollutant of aquatic habitats. During certain periods (e.g. winter), food deprivation may occur simultaneously in natural water. Additionally, under such stressful circumstances, fish may be enforced to swim at a high speed in order to catch prey, avoid predators and so on. Consequently, fish need to cope with all these stressors by altering physiological processes which in turn are controlled by their genes. In this present study, toxicogenomic analyses using real time PCR was used to characterize expression patterns of potential biomarker genes controlling growth, ion regulation and stress responses in common carp subjected to elevated ammonia (1mg/L; Flemish water quality guideline for surface water) following periods of feeding (2% body weight) and fasting (unfed for 7 days prior to sampling). Both feeding groups of fish were exposed to high environment ammonia (HEA) for 0h (control), 3h, 12h, 1day, 4days, 10days, 21days and 28days, and were sampled after performing swimming at different speeds (routine versus exhaustive). Results show that the activity and expression of Na+/K+-ATPase, an important branchial ion regulatory enzyme, was increased after 4–10 days of exposure. Effect of HEA was also evident on expression patterns of other ion-regulatory hormone and receptor genes; prolactin and cortisol receptor mRNA level(s) were down-regulated and up-regulated respectively after 4, 10 and 21 days. Starvation and exhaustive swimming, the additional challenges in present study significantly further enhanced the HEA effect on the expression of these two genes. mRNA transcript of growth regulating hormone and receptor genes such as Insulin-like growth factor I, growth hormone receptor, and the thyroid hormone receptor were reduced in response to HEA and the effect of ammonia was exacerbated in starved fish, with levels that were remarkably reduced compared to fed exposed fish. However, the expression of the growth hormone gene itself was up-regulated under the same conditions. Expression of somatolactin remained unaltered. Stress representative genes, cytochrome oxidase subunit 1 showed an up-regulation in response to HEA and starvation while the mRNA level of heat shock protein 70 was increased in response to all the three stressors. The expression kinetics of the studied genes could permit to develop a “molecular biomarker system” to identify the underlying physiological processes and impact of these stressors before effects at population level occur.

Combined effects of high environmental ammonia, starvation and exercise on hormonal and ion-regulatory response in goldfish (Carassius auratus L.)

Due to eutrophication, high environmental ammonia (HEA) has become a frequent problem in aquatic environments, especially in agricultural or densely populated areas. During certain periods, e.g. winter, feed deprivation may occur simultaneously in natural waters. Additionally, under such stressful circumstances, fish may be enforced to swim at a high speed in order to catch prey, avoid predators and so on. Consequently, fish need to cope with all these stressors by altering physiological processes which in turn are controlled by genes expression. Therefore, in the present study, ammonia toxicity was tested in function of nutrient status (fed versus starved) and swimming performance activity (routine versus exhaustive). Goldfish, a relatively tolerant cyprinid, were exposed to HEA (1mg/L; Flemish water quality guideline for surface water) for a period of 3h, 12h, 1 day, 4 days, 10 days, 21 days and 28 days and were either fed (2% body weight) or starved (kept unfed for 7 days prior to sampling). Results showed that the activity of Na+/K+-ATPase in the gills was stimulated by HEA and disturbance in ion balance was obvious with increases in plasma [Na+], [Cl−] and [Ca2+] after prolonged exposure. Additionally, osmoregulation and metabolism controlling hormones like cortisol and thyroid hormones (T3 and T4) were investigated to understand adaptive responses. The expression kinetics of growth, stress and osmo-regulatory representative genes such as Insulin-like growth factor 1 (IGF-I), growth hormone receptor (GHR), thyroid hormone receptor β (THRβ), prolactin receptor (PRLR), cortisol receptor (CR) and Na+/K+-ATPase α3 were examined. Overall effect of HEA was evident since Na+/K+-ATPase activity, plasma cortisol, Na+ and Ca2+ concentration, expression level of CR and Na+/K+-ATPase α3 mRNA in fed and starved fish were increased. On the contrary, transcript level of PRLR was reduced after 4 days of HEA; additionally T3 level and expression of GHR, IGF-I and THRβ genes were decreased following 10–21 days of HEA. Starvation, the additional challenge in the present study, significantly increased plasma cortisol level and CR transcript level under HEA compared to the fed exposed and control fish. Furthermore, a remarkable reduction in T3 and mRNA levels of THRβ, IGF-I and GHR genes was observed under starvation. The toxic effects in both feeding treatments were exacerbated when imposed to exhaustive swimming with more pronounced effects in starved fish. This confirms that starvation makes fish more vulnerable to external ammonia, especially during exercise.

Mountain bike wheel endurance testing and modeling

Mountain bike wheels may be evaluated for durability and mode of failure using bump drum test machines that subject wheels to simulated rider loads and uneven terrain. These machines may operate at high speeds in order to accelerate failures, particularly during the design and prototype phase of wheel development. This paper describes a mathematical model of the dynamics of a wheel test drum assembly, and the validation of the model using data recorded during a wheel test. This model will subsequently be applied to better understand the key test operating parameters that must be controlled in order to produce repeatable durability data during accelerated testing.

Micromachining of bipolar plates used in proton exchange membrane fuel cells

Bipolar Proton Exchange Membrane (PEM) fuel cell plates are composed of flat pieces of graphite with channels or trenches machined into the face of the plate so that gases can flow in the channels of the plate. The operation of the fuel cell is dependent on the flow of oxygen and hydrogen gases around a fuel cell stack, which is composed of many thin plates connected to each other in very close proximity. Owing to the brittle nature of graphite, bipolar plates are now made from nickel-chromium alloys that are coated with a thin solid layer of CrN or TiN to improve corrosion resistance. However, nickel-chromium alloys are notoriously difficult to machine. This paper describes the micromachining of fuel cell plates that are machined at very high speeds in order to produce high cutting tool life and low surface roughness using novel nanocrystalline diamond and titanium coatings that have been specifically designed to cut strain-hardening alloys at extremely high speeds.

TELMA—A Polish Wireless Communications Security Machine of World War II

The article discusses the history of development and use of a Polish wireless communications security machine of World War II, which was designed to send telegraphic messages at high speeds in order to avoid interception by Nazi German signals intelligence (SIGINT). It emphasizes the technological issues related to the design of the unit and the development of high speed keyers in agent radio operations. The article also briefly describes the measures related to signals intelligence, which improved the operational security in the Polish Home Army wireless service during the war.

Micromilling of bipolar fuel cell plates using titanium- and diamond-coated cutting tools

Bipolar Proton Exchange Membrane Fuel Cell (PEMFC) plates are composed of flat pieces of graphite with channels or trenches machined into the face of the plate so that gases can flow in the channels of the plate. The operation of the fuel cell is dependent on the flow of oxygen and hydrogen gases around the fuel cell stack, which is composed of many thin plates connected to each other in very close proximity. Owing to the brittle nature of graphite, bipolar plates are now made from experimental Nickel–Chromium (Ni–Cr) alloys that are coated with a thin solid layer of CrN or TiN to improve corrosion resistance. However, Ni–Cr alloys are notoriously difficult to machine. This paper describes the micromachining of fuel cell plates that are machined at very high speeds in order to produce high cutting tool life and low surface roughness using novel nanocrystalline diamond and titanium coatings that have been specifically designed to cut strain-hardening alloys at extremely high speeds.

Development of a high speed imaging microscope and new software for nuclear track detector analysis

Automated digital imaging optical microscopy is widely used for diagnostic applications in the health care and biology fields and for routine inspection in industrial applications such as semiconductor fabrication. These applications require the imaging of large areas at high speed in order to obtain sufficient data for image processing with good statistics. Track detector analysis also benefits from the rapid acquisition of large areas on the detector surface. We have developed a new microscope system, the HSP-1000, for high speed image acquisition that uses a line sensor camera in place of a traditional CCD camera. Continuous, automatic focusing of the microscope is achieved by means of an optical pick-up system that provides fast feedback for control of distance between the objective and the image surface. Using transmitted light illumination, the microscope is able to digitize a 1 cm 2 area at 0.35 μ m / pixel resolution in ∼ 20 s . As a result of continuous stage motion and continuous focusing, we have attained image acquisition speeds that are 50–100 times faster than conventional CCD-based microscope systems. In this paper, we describe a number of aspects of the microscope system including the use of the line sensor and the automatic focus system.

56.3: High Speed Flatbed Scanner for Large Format Display Manufacturing

AbstractSubstrate sizes in the Flat Panel Display (FPD) industry are constantly rising as manufacturers try to lower manufacturing costs and meet the ever growing demand for larger screens. The current forecast for Generation 7 (Gen 7) Liquid Crystal Display (LCD) mother‐glass format size is that it would exceed 2000 × 2000 mm. This situation poses a serious challenge to equipment manufacturers, and specifically to digital imaging equipment manufacturers, who need to find new methods to move these substrates at high speeds in order to achieve desired throughput levels.The conventional approach of supporting a substrate by a rigid chuck is not desirable since, for these large substrates, the moving mass becomes prohibitively large.A team in Creo Inc. has developed a novel approach where the moving substrate is supported by a lightweight flexible carrier which travels on an air‐bed (as in an “Air‐Hockey” table). Initial test results show that with such approach one could achieve excellent dynamic stability in a compact and lightweight system. Additional benefits include simpler motor design and thermal load management The concept together with test results will be presented.

Calibrating a special pulsating-flow velocity sensor for an electrical discharge CO2 laser

A detailed study has been made on the operation of a thermoanemometer at low pressures and fairly high speeds in order to calibrate the sensor for local fluctuations in the velocity of a turbulent gas flow under glow-discharge conditions. Aspects are considered of the measurement error for spectral and integral characteristics of a turbulent gas flow.

The upward transport of inclusions in Newtonian and power-law salt diapirs

This paper studies the ability of salt diapirs to lift large inclusions of dense rocks (rafts). Dense inclusions will be lifted if salt in the diapir rises faster than the inclusions sink. The power-law rheologies of six different salts, and viscosities estimated for Newtonian salt are used to calculate the settling velocity of these inclusions as a function of their radii and densiy as well as the temperature of the salt. This is done using the known equation describing the velocity of solid spheres settling in unbounded power-law fluid. Two-dimensional numerical models are used to study he effect of the ellipticity of inclusions on their sinking velocity, as a function of the power-law exponent n. The calculations of the settling velocities of inclusions neglect several other factors discussed in the paper: (a) the ambient fluid (salt) is finite (bounded); (b) more than one inclusion translates in the salt; (c) further strain-rate softening of salt is caused by its diapiric ascent. The results suggest that, whereas Newtonian salt of 10 17–10 18 Pa s and the power-law salt of the Vacherie Dome would have to rise at unreasonably high speeds in order to lift large inclusions, most power-law salt diapirs would be capable of lifting inclusions of the sizes observed in the Iranian domes (up to 3–6 km 2) if these rise at geologically reasonable velocities and temperatures.

Visual Inspection of Surface‐mounted Solder Joints

Electronics manufacturing throughout the world now uses an increasing percentage of Surface Mount Technology (SMT). The compact and light‐weight surface‐mounted components offer a number of advantages to manufacturers. Unfortunately, however, these same beneficial characteristics make the quality of the product difficult to guarantee. As miniaturisation continues, the inspection problem becomes worse, and so advanced methods of inspection are required. Automatic inspection systems already exist, although an effective, inexpensive and reliable system has yet to be found. Recent work carried out within the Coherent and Electro‐Optics Research Group at Liverpool Polytechnic has looked at the feasibility of applying some of its established inspection methods to the problem of solder joint inspection. Extensive development must still take place; however, the methods employed have shown promise. The system uses structured light techniques to add height information to an image of the solder joint under inspection. In this way a 3‐D image of the joint may be built up, digitised and processed in a computer at high speed in order to determine its quality.

Trichinella spiralis: Partial Characterization of Antigens Isolated by Immuno-Affinity Chromatography from the Large-Particle Fraction of the Muscle Larvae

A large-particle fraction, derived from muscle larvae of Trichinella spiralis by a combination of homogenization and differential centrifugation, was treated with 0.1% Triton X-100 and then centrifuged at high speed in order to obtain the soluble portion of this fraction (i.e., S3 fraction). The S3 fraction was then subjected to immuno-affinity chromatography. The antigens were eluted from the column using glycine-HCl buffer (pH 2.5). All 20 antigens were recovered from the S3 fraction in quantities that permitted physical, chemical, and biological determinations to be made on them. Antigens analyzed on SDS-PAGE ranged in molecular weight from 105,000 to 11,000 daltons Their isoelectric points were estimated with slab gel isoelectric focusing and ranged in pI from 4.0 to 9.0. The column-purified antigens were injected into mice together with an equal volume of Freund's complete adjuvant, and 2 wk later all mice were each challenged with 200 muscle larvae given orally. Immunized mice harbored 84% fewer muscle larvae at day 30 postinfection than controls, and were as immune as those mice receiving whole S3 (86% reduction). These results showed that protection-inducing antigens can be separated from the nonprotective portion of the muscle larva by immuno-affinity chromatography without loss of protection-inducing activity.

Control of Traffic by Light Signals

THE earliest light signals for controlling traffic were operated manually by the police. The next type were operated on a ‘fixed-time’ basis by purely mechanical devices. A later development is to link up a number of local fixed-time controllers with a master controller so that the indications all along a main traffic route bear a definite relationship to one another, with the object of maintaining a steady flow of traffic. An important example of this type is installed in Oxford Street, London. The latest and most popular types of signals are those which are operated by the passing vehicles themselves. There are two systems of this type in general use, and both use a detector mat placed in the roadway. In one system, the compression of the mat actuates an electro-pneumatic contact box placed in the pave ment and only responds when the vehicle is approach ing the crossing. A vehicle ‘parking’ on the mat has no effect on the signal. Suspended signals, which are fairly common abroad, divert the attention of the driver from the road level, and the drivers of modern saloon cars have difficulty in seeing them. The British signals are sometimes criticised because,unlike the ‘clock-face’ or ‘Chinese-lantern’ type of signal used frequently in Switzerland and Germany, they give no indication of the length of time that the red or green indication has to remain. They are objectionable as they induce many drivers to ac celerate to high speeds in order to pass the signals before they change. The uncertainty of the time of change in the usual type forces the driver to go slowly and this leads to safety. It is probable that vehicle-actuated signals will come into general use in England, and this would make ‘clock-face’ signals with their fixed time sequence of events practically impossible. An illustrated article on “Traffic Light Control Systems” appears in Electrical Industries of November 15.