Detection Process (detection + process)

Distribution by Scientific Domains


Selected Abstracts


Auditor Detected Misstatements and the Effect of Information Technology

INTERNATIONAL JOURNAL OF AUDITING, Issue 3 2004
William F. Messier Jr.
This paper presents information on the causes and detection of misstatements by auditors and the relationship of those misstatements with information technology (IT). The last major study of misstatements and IT used data that were gathered in 1988. In the intervening period, there have been significant changes in IT, possibly altering the error generation and detection process. Two research questions related to detected misstatements and the effect of IT are examined. The six largest public accounting firms in Norway provided data from 58 engagements. We find that (1) the major causes of misstatements were missing, poorly designed, and improperly applied controls; inadequate methods used to select, train and supervise accounting personnel; and an excessive workload for accounting personnel, (2) missing and poorly designed controls, and excessive workload for accounting personnel were more likely to be causes of misstatements in computerized business processes than those that were not computerized, and (3) the increased use of tests of details over attention directing procedures on audits appears to result from auditors deciding that it is more effective or efficient to conduct such tests than rely upon IT controls. These findings have important implications for both audit practitioners and researchers. [source]


Low-cost solution to on-line color filter array demosaicking

INTERNATIONAL JOURNAL OF IMAGING SYSTEMS AND TECHNOLOGY, Issue 4 2007
Gökhan Kabukcu
Abstract The article introduces a low-cost algorithm for improving the demosaicking process in the texture areas such as one-pixel patterns. The algorithm first detects difficult texture regions. After the detection process is completed, the algorithm demosaicks the texture areas using special demosaicking operations whereas non-texture regions are restored using some of the existing demosaicking approaches. In this way, the quality of the texture areas in demosaicked images can be improved up to 70% while only little increasing the computational complexity of the original demosaicking solution. © 2007 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 17, 232,243, 2007 [source]


Selective Detection of Trace Nitroaromatic, Nitramine, and Nitrate Ester Explosive Residues Using a Three-Step Fluorimetric Sensing Process: A Tandem Turn-off, Turn-on Sensor,

JOURNAL OF FORENSIC SCIENCES, Issue 6 2007
Jason C. Sanchez M.S.
Abstract:, Detection of trace quantities of explosive residues plays a key role in military, civilian, and counter-terrorism applications. To advance explosives sensor technology, current methods will need to become cheaper and portable while maintaining sensitivity and selectivity. The detection of common explosives including trinitrotoluene (TNT), cyclotrimethylenetrinitramine, cyclotetramethylene-tetranitramine, pentaerythritol tetranitrate, 2,4,6-trinitrophenyl-N-methylnitramine, and trinitroglycerin may be carried out using a three-step process combining "turn-off" and "turn-on" fluorimetric sensing. This process first detects nitroaromatic explosives by their quenching of green luminescence of polymetalloles (,em , 400,510 nm). The second step places down a thin film of 2,3-diaminonaphthalene (DAN) while "erasing" the polymetallole luminescence. The final step completes the reaction of the nitramines and/or nitrate esters with DAN resulting in the formation of a blue luminescent traizole complex (,em = 450 nm) providing a "turn-on" response for nitramine and nitrate ester-based explosives. Detection limits as low as 2 ng are observed. Solid-state detection of production line explosives demonstrates the applicability of this method to real world situations. This method offers a sensitive and selective detection process for a diverse group of the most common high explosives used in military and terrorist applications today. [source]


Silicon drift and pixel devices for X-ray imaging and spectroscopy

JOURNAL OF SYNCHROTRON RADIATION, Issue 2 2006
G. Lutz
Starting from the basic photon detection process in semiconductors, the function, principles and properties of sophisticated silicon detectors are discussed. These detectors are based on, or inspired by, the semiconductor drift detector. They have already shown their potential in X-ray astronomy (pn-CCD) and in X-ray spectroscopy (silicon drift diode), and further detector types (DEPFET pixel detector and macro-pixel detector) are under development for several other future experiments. The detectors seem to be very well suited for synchrotron radiation experiments. [source]


Improving kp Data Originating from PLP Number Distributions

MACROMOLECULAR THEORY AND SIMULATIONS, Issue 3 2006
Andreas Kornherr
Abstract Summary: Based on certain features, especially the width of the so-called extra peaks in the simulated number-chain-length distribution (CLD) of polymers prepared by pulsed laser polymerization (PLP), it is calculated by which factor the positions of the points of inflections and maxima deviate from the theoretical L0 data that are to be used for the evaluation of kp. These corrections are for slightly chain-length-dependent termination by disproportionation or combination and cover a wide range of chain-lengths and primary radical production. They can be applied either to the point of inflection on the low-molecular weight side of the extra peaks or to the peak maximum. On average, the mean error that is about ,2.5% for uncorrected data from first-order points of inflection is reduced to the order of less than 1% even if no assumption concerning the mode of termination is made. The situation is similar for the positions of the first-order peak maxima where the mean error of about +7% likewise can be cut down to less than 1% if the proper correction function is chosen. Second- and third-order peaks data, which are a priori less falsified, yield still better results after correction. Mass sensitivity of the detection process has comparatively little effect: it is only for unrealistically high extents of chain-length dependence in detection that considerable falsifications are to be expected. As an additional result it turned out that correction functions obtained for number distributions are also applicable to mass spectrometry raw distributions and even for mass distributions x(l),·,l provided Poissonian broadening is the only broadening process. Number distribution xC(l) calculated for termination by combination times attenuation function F1(l). [source]


Bias in attending to emotional facial expressions: Anxiety and visual search efficiency

APPLIED COGNITIVE PSYCHOLOGY, Issue 3 2010
Eriko Matsumoto
There has been much controversy around the relationship between anxiety and attentional processing of threat-related information. The purpose of this study was to examine how threatening facial expressions affect attentional processing, according to the level of trait anxiety. Through visual search tasks, two different components of attentional bias to threat were investigated: engagement and disengagement of attention from an angry face. Two main results were found. First, reaction times (RTs) were slower in detecting the absence of a discrepant face in the all angry-display conditions rather than other expression conditions; however, there was no difference between anxiety groups. Second, the difference in search efficiency for the angry versus happy target was significant within the high-anxiety group but not within the low-anxiety group. The results suggest that the detection process for angry faces is more efficient for highly anxious people. On the other hand, the time to disengage attention from angry faces was not associated with anxiety level. Copyright © 2010 John Wiley & Sons, Ltd. [source]


Carbon nanotube/poly(methyl methacrylate) composite electrode for capillary electrophoretic measurement of honokiol and magnolol in Cortex Magnoliae Officinalis

ELECTROPHORESIS, Issue 16 2006
Xiao Yao
Abstract This paper describes the development and the application of a novel carbon nanotube/poly(methyl methacrylate) (CNT/PMMA) composite electrode as a sensitive amperometric detector of CE. The composite electrode was fabricated on the basis of the in,situ polymerization of a mixture of CNT and prepolymerized methylmethacrylate in the microchannel of a piece of fused-silica capillary under heat. The performance of this unique system has been demonstrated by separating and detecting honokiol and magnolol in traditional Chinese medicine, Cortex Magnoliae Officinalis. Factors influencing their separation and detection processes were examined and optimized. Honokiol and magnolol were well separated within 7,min in a 40 cm long capillary at a separation voltage of 15,kV using a 50 mM borate buffer (pH,9.2). The new CNT-based CE detector offered significantly lower operating potentials, yielded substantially enhanced S/N characteristics, and exhibited resistance to surface fouling and hence enhanced stability. It demonstrated long-term stability and reproducibility with RSDs of less than 5% for the peak current (n = 9) and should also find a wide range of applications in microchip CE, flowing injection analysis, and other microfluidic analysis systems. [source]


Poly(methylmethacrylate) and Topas capillary electrophoresis microchip performance with electrochemical detection

ELECTROPHORESIS, Issue 16 2005
Mario Castańo-Álvarez
Abstract A capillary electrophoresis (CE) microchip made of a new and promising polymeric material: Topas (thermoplastic olefin polymer of amorphous structure), a cyclic olefin copolymer with high chemical resistance, has been tested for the first time with analytical purposes, employing an electrochemical detection. A simple end-channel platinum amperometric detector has been designed, checked, and optimized in a poly-(methylmethacrylate) (PMMA) CE microchip. The end-channel design is based on a platinum wire manually aligned at the exit of the separation channel. This is a simple and durable detection in which the working electrode is not pretreated. H2O2 was employed as model analyte to study the performance of the PMMA microchip and the detector. Factors influencing migration and detection processes were examined and optimized. Separation of H2O2 and L -ascorbic acid (AsA) was developed in order to evaluate the efficiency of microchips using different buffer systems. This detection has been checked for the first time with a microchip made of Topas, obtaining a good linear relationship for mixtures of H2O2 and AsA in different buffers. [source]