Search results for: single shot multibox detector
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 5028

Search results for: single shot multibox detector

3978 Benefits of Hybrid Mix in Renewable Energy and Integration with E-Efficient Compositions

Authors: Ahmed Khalil

Abstract:

Increased energy demands around the world have led to the raise in power production which has resulted with more greenhouse gas emissions through fossil sources. These fossil sources and emissions cause deterioration in echo-system. Therefore, renewable energy sources come to the scene as echo-friendly and clean energy sourcing, whereas the electrical devices and energy needs decrease in the timeline. Each of these renewable energy sources contribute to the reduction of greenhouse gases and mitigate environmental deterioration. However, there are also some general and source-specific challenges, which influence the choice of the investors. The most prominent general challenge that effects end-users’ comfort and reliability is usually determined as the intermittence which derives from the diversions of source conditions, due to nature dynamics and uncontrolled periodic changes. Research and development professionals strive to mitigate intermittence challenge through material improvement for each renewable source whereas hybrid source mix stand as a solution. This solution prevails well, when single renewable technologies are upgraded further. On the other hand, integration of energy efficient devices and systems, raise the affirmative effect of such solution in means of less energy requirement in sustainability composition or scenario. This paper provides a glimpse on the advantages of composing renewable source mix versus single usage, with contribution of sampled e-efficient systems and devices. Accordingly it demonstrates the extended benefits, through planning and predictive estimation stages of Ahmadi Town Projects in Kuwait.

Keywords: e-efficient systems, hybrid source, intermittence challenge, renewable energy

Procedia PDF Downloads 136
3977 Application of Lattice Boltzmann Method to Different Boundary Conditions in a Two Dimensional Enclosure

Authors: Jean Yves Trepanier, Sami Ammar, Sagnik Banik

Abstract:

Lattice Boltzmann Method has been advantageous in simulating complex boundary conditions and solving for fluid flow parameters by streaming and collision processes. This paper includes the study of three different test cases in a confined domain using the method of the Lattice Boltzmann model. 1. An SRT (Single Relaxation Time) approach in the Lattice Boltzmann model is used to simulate Lid Driven Cavity flow for different Reynolds Number (100, 400 and 1000) with a domain aspect ratio of 1, i.e., square cavity. A moment-based boundary condition is used for more accurate results. 2. A Thermal Lattice BGK (Bhatnagar-Gross-Krook) Model is developed for the Rayleigh Benard convection for both test cases - Horizontal and Vertical Temperature difference, considered separately for a Boussinesq incompressible fluid. The Rayleigh number is varied for both the test cases (10^3 ≤ Ra ≤ 10^6) keeping the Prandtl number at 0.71. A stability criteria with a precise forcing scheme is used for a greater level of accuracy. 3. The phase change problem governed by the heat-conduction equation is studied using the enthalpy based Lattice Boltzmann Model with a single iteration for each time step, thus reducing the computational time. A double distribution function approach with D2Q9 (density) model and D2Q5 (temperature) model are used for two different test cases-the conduction dominated melting and the convection dominated melting. The solidification process is also simulated using the enthalpy based method with a single distribution function using the D2Q5 model to provide a better understanding of the heat transport phenomenon. The domain for the test cases has an aspect ratio of 2 with some exceptions for a square cavity. An approximate velocity scale is chosen to ensure that the simulations are within the incompressible regime. Different parameters like velocities, temperature, Nusselt number, etc. are calculated for a comparative study with the existing works of literature. The simulated results demonstrate excellent agreement with the existing benchmark solution within an error limit of ± 0.05 implicates the viability of this method for complex fluid flow problems.

Keywords: BGK, Nusselt, Prandtl, Rayleigh, SRT

Procedia PDF Downloads 128
3976 Death Anxiety, Quality of Life, and Self-Esteem of the Elderly in Surat Thani Province, Thailand

Authors: W. Phokhwang-Just, A. Saraketrin, P. Thongpet, J. Udomkitpipat, J. Kaewsakulthong

Abstract:

The more people get older and live longer, the more health problems they may have. This cross-sectional study aims to study a correlation between death anxiety, quality of life, and self-esteem as well as factors affecting these variables in the elderly living in Surat Thani Province, Thailand. Of 382 elderly people, who were proportionally sampled from 19 districts in Surat Thani Province, 256 (67%) already returned the questionnaires. The Thai version of Templer’s Death Anxiety, Quality of Life (WHO-BREF), and of Rosenberg’s Self-Esteem Questionnaires were employed. The result showed that the samples had a mean age of 72 years old, 53% were female, 62% were married, 61% graduated with primary-school, and 61% had at least one chronic disease Approximately, 19% of them had 3 diseases. The quality of life (QOL), self-esteem (SE), and death anxiety (DA) of samples were in moderate (n= 91, mean = 86.89, SD = 15.47), high (n = 138, mean = 29.33, SD=4.77), and low level (n= 85, mean = 6.23, SD= 3.65), respectively. The QOL was not significantly different between male and female as well as among different marital status. The female elderly had more DA and less SE than male (t= 2.095, df = 83; t =-3.258, df =135, respectively, p < 0.05). The female elderly, who were separated or widow, had a higher level of DA than did the married elderly (LSD: p < 0.05). The married elderly had a higher level of SE than did the separated, widowed (Tukey HSD, LSD: p < 0.05), or single elderly (LSD: p < 0.05). The more diseases the elderly got, the lower level of QOL they had (r = -0.335, p < 0.05). The QOL was significantly correlated with SE (r =0.434, p < 0.05), but not significantly related to DA (r = -0.200, p = 0.069). The lower level of SE the elderly had, the higher level of DA they become (r = -2.71, p < 0.05). In order to promote the QOL, the SE of the elderly should be enhanced. Consequently, the DA can be minimized. Healthcare providers should provide care that promotes QOL, SE, and reduces DA of the elderly, especially those, who are female, single, and separated or widowed as well as those, who have more diseases than the others

Keywords: death anxiety, quality of life, self-esteem, elderly

Procedia PDF Downloads 308
3975 A Differential Detection Method for Chip-Scale Spin-Exchange Relaxation Free Atomic Magnetometer

Authors: Yi Zhang, Yuan Tian, Jiehua Chen, Sihong Gu

Abstract:

Chip-scale spin-exchange relaxation free (SERF) atomic magnetometer makes use of millimeter-scale vapor cells micro-fabricated by Micro-electromechanical Systems (MEMS) technique and SERF mechanism, resulting in the characteristics of high spatial resolution and high sensitivity. It is useful for biomagnetic imaging including magnetoencephalography and magnetocardiography. In a prevailing scheme, circularly polarized on-resonance laser beam is adapted for both pumping and probing the atomic polarization. And the magnetic-field-sensitive signal is extracted by transmission laser intensity enhancement as a result of atomic polarization increase on zero field level crossing resonance. The scheme is very suitable for integration, however, the laser amplitude modulation (AM) noise and laser frequency modulation to amplitude modulation (FM-AM) noise is superimposed on the photon shot noise reducing the signal to noise ratio (SNR). To suppress AM and FM-AM noise the paper puts forward a novel scheme which adopts circularly polarized on-resonance light pumping and linearly polarized frequency-detuning laser probing. The transmission beam is divided into transmission and reflection beams by a polarization analyzer, the angle between the analyzer's transmission polarization axis and frequency-detuning laser polarization direction is set to 45°. The magnetic-field-sensitive signal is extracted by polarization rotation enhancement of frequency-detuning laser which induces two beams intensity difference increase as the atomic polarization increases. Therefore, AM and FM-AM noise in two beams are common-mode and can be almost entirely canceled by differential detection. We have carried out an experiment to study our scheme. The experiment reveals that the noise in the differential signal is obviously smaller than that in each beam. The scheme is promising to be applied for developing more sensitive chip-scale magnetometer.

Keywords: atomic magnetometer, chip scale, differential detection, spin-exchange relaxation free

Procedia PDF Downloads 170
3974 Challenges in Early Diagnosis of Enlarged Vestibular Aqueduct (EVA) in Pediatric Population: A Single Case Report

Authors: Asha Manoharan, Sooraj A. O, Anju K. G

Abstract:

Enlarged vestibular aqueduct (EVA) refers to the presence of congenital sensorineural hearing loss with an enlarged vestibular aqueduct. The Audiological symptoms of EVA are fluctuating and progressive in nature and the diagnosis of EVAS can be confirmed only with radiological evaluation. Hence it is difficult to differentiate EVA from conditions like Meniere’s disease, semi-circular dehiscence, etc based on audiological findings alone. EVA in adults is easy to identify due to distinct vestibular symptoms. In children, EVA can remain either unidentified or misdiagnosed until the vestibular symptoms are evident. Motor developmental delay, especially the ones involving a change of body alignment, has been reported in the pediatric population with EVA. So, it should be made mandatory to recommend radiological evaluation in young children with fluctuating hearing loss reporting with motor developmental delay. This single case study of a baby with Enlarged Vestibular Aqueduct (EVA) primarily aimed to address the following: a) Challenges while diagnosing young patients with EVA and fluctuating hearing loss, b) Importance of radiological evaluation in audiological diagnosis in the pediatric population, c) Need for regular monitoring of hearing, hearing aid performance, and cochlear implant mapping closely for potential fluctuations in such populations, d) Importance of reviewing developmental, language milestones in very young children with fluctuating hearing loss.

Keywords: enlarged vestibular aqueduct (EVA), motor delay, radiological evaluation, fluctuating hearing loss, cochlear implant

Procedia PDF Downloads 167
3973 The Effect of Manure Loaded Biochar on Soil Microbial Communities

Authors: T. Weber, D. MacKenzie

Abstract:

The script in this paper describes the use of advanced simulation environment using electronic systems (microcontroller, operational amplifiers, and FPGA). The simulation was used for non-linear dynamic systems behaviour with required observer structure working with parallel real-time simulation based on state-space representation. The proposed deposited model was used for electrodynamic effects including ionising effects and eddy current distribution also. With the script and proposed method, it is possible to calculate the spatial distribution of the electromagnetic fields in real-time and such systems. For further purpose, the spatial temperature distribution may also be used. With upon system, the uncertainties and disturbances may be determined. This provides the estimation of the more precise system states for the required system and additionally the estimation of the ionising disturbances that arise due to radiation effects in space systems. The results have also shown that a system can be developed specifically with the real-time calculation (estimation) of the radiation effects only. Electronic systems can take damage caused by impacts with charged particle flux in space or radiation environment. TID (Total Ionising Dose) of 1 Gy and Single Effect Transient (SET) free operation up to 50 MeVcm²/mg may assure certain functions. Single-Event Latch-up (SEL) results on the placement of several transistors in the shared substrate of an integrated circuit; ionising radiation can activate an additional parasitic thyristor. This short circuit between semiconductor-elements can destroy the device without protection and measurements. Single-Event Burnout (SEB) on the other hand, increases current between drain and source of a MOSFET and destroys the component in a short time. A Single-Event Gate Rupture (SEGR) can destroy a dielectric of semiconductor also. In order to be able to react to these processes, it must be calculated within a shorter time that ionizing radiation and dose is present. For this purpose, sensors may be used for the realistic evaluation of the diffusion and ionizing effects of the test system. For this purpose, the Peltier element is used for the evaluation of the dynamic temperature increases (dT/dt), from which a measure of the ionization processes and thus radiation will be detected. In addition, the piezo element may be used to record highly dynamic vibrations and oscillations to absorb impacts of charged particle flux. All available sensors shall be used to calibrate the spatial distributions also. By measured value of size and known location of the sensors, the entire distribution in space can be calculated retroactively or more accurately. With the formation, the type of ionisation and the direct effect to the systems and thus possible prevent processes can be activated up to the shutdown. The results show possibilities to perform more qualitative and faster simulations independent of space-systems and radiation environment also. The paper gives additionally an overview of the diffusion effects and their mechanisms.

Keywords: cattle, biochar, manure, microbial activity

Procedia PDF Downloads 103
3972 External Noise Distillation in Quantum Holography with Undetected Light

Authors: Sebastian Töpfer, Jorge Fuenzalida, Marta Gilaberte Basset, Juan P. Torres, Markus Gräfe

Abstract:

This work presents an experimental and theoretical study about the noise resilience of quantum holography with undetected photons. Quantum imaging has become an important research topic in the recent years after its first publication in 2014. Following this research, advances towards different spectral ranges in detection and different optical geometries have been made. Especially an interest in the field of near infrared to mid infrared measurements has developed, because of the unique characteristic, that allows to sample a probe with photons in a different wavelength than the photons arriving at the detector. This promising effect can be used for medical applications, to measure in the so-called molecule fingerprint region, while using broadly available detectors for the visible spectral range. Further advance the development of quantum imaging methods have been made by new measurement and detection schemes. One of which is quantum holography with undetected light. It combines digital phase shifting holography with quantum imaging to extent the obtainable sample information, by measuring not only the object transmission, but also its influence on the phase shift experienced by the transmitted light. This work will present extended research for the quantum holography with undetected light scheme regarding the influence of external noise. It is shown experimentally and theoretically that the samples information can still be at noise levels of 250 times higher than the signal level, because of its information being transmitted by the interferometric pattern. A detailed theoretic explanation is also provided.

Keywords: distillation, quantum holography, quantum imaging, quantum metrology

Procedia PDF Downloads 75
3971 Design and Assessment of Base Isolated Structures under Spectrum-Compatible Bidirectional Earthquakes

Authors: Marco Furinghetti, Alberto Pavese, Michele Rinaldi

Abstract:

Concave Surface Slider devices have been more and more used in real applications for seismic protection of both bridge and building structures. Several research activities have been carried out, in order to investigate the lateral response of such a typology of devices, and a reasonably high level of knowledge has been reached. If radial analysis is performed, the frictional force is always aligned with respect to the restoring force, whereas under bidirectional seismic events, a bi-axial interaction of the directions of motion occurs, due to the step-wise projection of the main frictional force, which is assumed to be aligned to the trajectory of the isolator. Nonetheless, if non-linear time history analyses have to be performed, standard codes provide precise rules for the definition of an averagely spectrum-compatible set of accelerograms in radial conditions, whereas for bidirectional motions different combinations of the single components spectra can be found. Moreover, nowadays software for the adjustment of natural accelerograms are available, which lead to a higher quality of spectrum-compatibility and to a smaller dispersion of results for radial motions. In this endeavor a simplified design procedure is defined, for building structures, base-isolated by means of Concave Surface Slider devices. Different case study structures have been analyzed. In a first stage, the capacity curve has been computed, by means of non-linear static analyses on the fixed-base structures: inelastic fiber elements have been adopted and different direction angles of lateral forces have been studied. Thanks to these results, a linear elastic Finite Element Model has been defined, characterized by the same global stiffness of the linear elastic branch of the non-linear capacity curve. Then, non-linear time history analyses have been performed on the base-isolated structures, by applying seven bidirectional seismic events. The spectrum-compatibility of bidirectional earthquakes has been studied, by considering different combinations of single components and adjusting single records: thanks to the proposed procedure, results have shown a small dispersion and a good agreement in comparison to the assumed design values.

Keywords: concave surface slider, spectrum-compatibility, bidirectional earthquake, base isolation

Procedia PDF Downloads 292
3970 Microstructural Origin of Morphotropic Phase Boundary and Magnetic Ordering in the Multiferroic BiFeO3-PbTiO3

Authors: Bastola Narayan, Rajeev Ranjan

Abstract:

The morphotropic phase boundary (MPB) in the magnetoelectric (1-x)BiFeO3-(x)PbTiO3 has remained a matter of controversy ever since its discovery in 1964. The nature of the phase stabilized (single phase tetragonal or coexistence of tetragonal and rhombohedral phases) is very sensitive to the slight changes in the synthesis conditions. It thus remained an enigma as to what is the essential physical factor which is controlled by the slight difference in the synthesis conditions that finally determines, whether the phase formed will be single phase or coexistence of phases. In this paper, we demonstrate that the nature of the phase stabilized in this system is uniquely dependent on the crystallite size. The system is shown to exhibit features of abnormal grain growth (AGG) during sintering with abrupt increase in the grain size from ~ 1 micron to ~ 10 microns. The 10 micron grains exhibit pure tetragonal phase while the 1 micron grains exhibit coexistence of rhombohedral and tetragonal ferroelectric phases. The Rietveld analysis of powder neutron diffraction shows a paramagnetic to antiferromagnetic order transition inducing with crystalline size reduction from 10 micron to 1 micron. Since tetragonal phase is known to have paramagnetic order and rhombohedral phase has antiferromagnetic order in room temperature, this further strengthens our argument of size induced structure transition.

Keywords: size driven MPB, size driven magnetic ordering, abnormal grain growth, phase formation in BF-PT system

Procedia PDF Downloads 335
3969 Evaluation of Chemical Compositions and Biological Activities of Five Essential Oils

Authors: G. Ozturk, B. Demirci

Abstract:

It is well known that essential oils used for therapeutic purposes for many years. In this study, five different Pharmacopoeia grade essential oils (Achillea millefolium L., Pimpinella anisum L., Matricaria recutita L., Eucalyptus globulus L., Salvia officinalis L.) which obtained from commercial sources were evaluated for chemical compositions, synergistic antimicrobial activities, and lipoxygenase enzyme inhibitions. Volatile components were determined by gas chromatography/flame ionization detector and gas chromatography/mass spectrometer, simultaneously. The potential antimicrobial activity of essential oils was tested against oral pathogenic standard strains such as Streptococcus mutans, Streptococcus sanguinis, Staphylococcus aureus, Corynebacterium striatum, Candida albicans and Candida krusei by broth microdilution methods. Ciprofloxacin and ketoconazole were used positive controls. It has been observed that the essential oils tested have average inhibitory antimicrobial activity against oral pathogens with a Minimum Inhibition Concentration of 20-0.625 mg/mL. The active essential oils have been combined with antibiotics and synergistic effects have been evaluated by Checkerboard method. ƩFIC values were determined. In combination with antibiotics M. recutita essential oil has been shown to have a synergistic effect against S. aureus in combination with tetracycline (ƩFIC 0.46). In addition, 5-LOX inhibitory activity was measured by modifying the spectrophotometric method developed by Baylac and Racine. As a result, 5-LOX % inhibition of S. officinalis, E. globulus and M. recutita were calculated as 34.0 ± 6.66, 72.7 ± 2.78 and 27.7 ± 0.60, respectively.

Keywords: antimicrobial activity, essential oils, synergistic activity, 5-lipoxygenase inhibition

Procedia PDF Downloads 105
3968 Uncertainty Evaluation of Erosion Volume Measurement Using Coordinate Measuring Machine

Authors: Mohamed Dhouibi, Bogdan Stirbu, Chabotier André, Marc Pirlot

Abstract:

Internal barrel wear is a major factor affecting the performance of small caliber guns in their different life phases. Wear analysis is, therefore, a very important process for understanding how wear occurs, where it takes place, and how it spreads with the aim on improving the accuracy and effectiveness of small caliber weapons. This paper discusses the measurement and analysis of combustion chamber wear for a small-caliber gun using a Coordinate Measuring Machine (CMM). Initially, two different NATO small caliber guns: 5.56x45mm and 7.62x51mm, are considered. A Micura Zeiss Coordinate Measuring Machine (CMM) equipped with the VAST XTR gold high-end sensor is used to measure the inner profile of the two guns every 300-shot cycle. The CMM parameters, such us (i) the measuring force, (ii) the measured points, (iii) the time of masking, and (iv) the scanning velocity, are investigated. In order to ensure minimum measurement error, a statistical analysis is adopted to select the reliable CMM parameters combination. Next, two measurement strategies are developed to capture the shape and the volume of each gun chamber. Thus, a task-specific measurement uncertainty (TSMU) analysis is carried out for each measurement plan. Different approaches of TSMU evaluation have been proposed in the literature. This paper discusses two different techniques. The first is the substitution method described in ISO 15530 part 3. This approach is based on the use of calibrated workpieces with similar shape and size as the measured part. The second is the Monte Carlo simulation method presented in ISO 15530 part 4. Uncertainty evaluation software (UES), also known as the Virtual Coordinate Measuring Machine (VCMM), is utilized in this technique to perform a point-by-point simulation of the measurements. To conclude, a comparison between both approaches is performed. Finally, the results of the measurements are verified through calibrated gauges of several dimensions specially designed for the two barrels. On this basis, an experimental database is developed for further analysis aiming to quantify the relationship between the volume of wear and the muzzle velocity of small caliber guns.

Keywords: coordinate measuring machine, measurement uncertainty, erosion and wear volume, small caliber guns

Procedia PDF Downloads 150
3967 Transperineal Repair Is Ideal for the Management of Rectocele with Faecal Incontinence

Authors: Tia Morosin, Marie Shella De Robles

Abstract:

Rectocele may be associated with symptoms of both obstructed defecation and faecal incontinence. Currently, numerous operative techniques exist to treat patients with rectocele; however, no single technique has emerged as the optimal approach in patients with post-partum faecal incontinence. The purpose of this study was to evaluate the clinical outcome in a consecutive series of patients who underwent transperineal repair of rectocele for patients presenting with faecal incontinence as the predominant symptom. Twenty-three consecutive patients from April 2000 to July 2015 with symptomatic rectocele underwent transperineal repair by a single surgeon. All patients had a history of vaginal delivery, with or without evidence of associated anal sphincter injury at the time. The median age of the cohort was 53 years (range 21 to 90 years). The median operating time and length of hospital stay were 2 hours and 7 days, respectively. Two patients developed urinary retention post-operatively, which required temporary bladder catheterization. One patient had wound dehiscence, which was managed by absorbent dressing applied by the patient and her carer. There was no operative mortality. In all patients with rectocele, there was a concomitant anal sphincter disruption. All patients had satisfactory improvement with regard to faecal incontinence on follow-up. This study suggests this method provides excellent anatomic and physiologic results with minimal morbidity. However, because none of the patients gained full continence postoperatively, pelvic floor rehabilitation might be also needed to achieve better sphincter function in patients with incontinence.

Keywords: anal sphincter defect, faecal incontinence, rectocele, transperineal repair

Procedia PDF Downloads 127
3966 Soft Pneumatic Actuators Fabricated Using Soluble Polymer Inserts and a Single-Pour System for Improved Durability

Authors: Alexander Harrison Greer, Edward King, Elijah Lee, Safa Obuz, Ruhao Sun, Aditya Sardesai, Toby Ma, Daniel Chow, Bryce Broadus, Calvin Costner, Troy Barnes, Biagio DeSimone, Yeshwin Sankuratri, Yiheng Chen, Holly Golecki

Abstract:

Although a relatively new field, soft robotics is experiencing a rise in applicability in the secondary school setting through The Soft Robotics Toolkit, shared fabrication resources and a design competition. Exposing students outside of university research groups to this rapidly growing field allows for development of the soft robotics industry in new and imaginative ways. Soft robotic actuators have remained difficult to implement in classrooms because of their relative cost or difficulty of fabrication. Traditionally, a two-part molding system is used; however, this configuration often results in delamination. In an effort to make soft robotics more accessible to young students, we aim to develop a simple, single-mold method of fabricating soft robotic actuators from common household materials. These actuators are made by embedding a soluble polymer insert into silicone. These inserts can be made from hand-cut polystyrene, 3D-printed polyvinyl alcohol (PVA) or acrylonitrile butadiene styrene (ABS), or molded sugar. The insert is then dissolved using an appropriate solvent such as water or acetone, leaving behind a negative form which can be pneumatically actuated. The resulting actuators are seamless, eliminating the instability of adhering multiple layers together. The benefit of this approach is twofold: it simplifies the process of creating a soft robotic actuator, and in turn, increases its effectiveness and durability. To quantify the increased durability of the single-mold actuator, it was tested against the traditional two-part mold. The single-mold actuator could withstand actuation at 20psi for 20 times the duration when compared to the traditional method. The ease of fabrication of these actuators makes them more accessible to hobbyists and students in classrooms. After developing these actuators, they were applied, in collaboration with a ceramics teacher at our school, to a glove used to transfer nuanced hand motions used to throw pottery from an expert artist to a novice. We quantified the improvement in the users’ pottery-making skill when wearing the glove using image analysis software. The seamless actuators proved to be robust in this dynamic environment. Seamless soft robotic actuators created by high school students show the applicability of the Soft Robotics Toolkit for secondary STEM education and outreach. Making students aware of what is possible through projects like this will inspire the next generation of innovators in materials science and robotics.

Keywords: pneumatic actuator fabrication, soft robotic glove, soluble polymers, STEM outreach

Procedia PDF Downloads 134
3965 Spatial and Seasonal Distribution of Persistent Organic Pollutant (Polychlorinated Biphenyl) Along the Course of Buffalo River, Eastern Cape Province, South Africa

Authors: Abdulrazaq Yahaya, Omobola Okoh, Anthony Okoh

Abstract:

Polychlorinated biphenyls (PCBs) are generated from short emission or leakage from capacitors and electrical transformers, industrial chemicals wastewater discharge and careless disposal of wastes. They are toxic, semi-volatile compounds which can persist in the environment, hence classified as persistent organic pollutants. Their presence in the environmental matrices has become a global concern. In this study, we assessed the concentrations and distribution patterns of 19 polychlorinated biphenyls congeners (PCB 1, 5, 18, 31, 44, 52, 66, 87, 101, 110, 138, 141, 151, 153, 170, 180, 183, 187, and 206) at six sampling points in water along the course of Buffalo River, Eastern Cape, South Africa. Solvent extraction followed by sulphuric acid, potassium permanganate and silica gel cleanup were used in this study. The analysis was done with gas chromatography electron capture detector (GC-ECD). The results of the analysis of all the 19 PCBs congeners ranged from not detectable to 0.52 ppb and 2.5 ppb during summer and autumn periods respectively. These values are generally higher than the World Health Organization (WHO) maximum permissible limit. Their presence in the waterbody suggests an increase in anthropogenic activities over the seasons. In view of their volatility, the compounds are transportable over long distances by air currents away from their point of origin putting the health of the communities at risk, thus suggesting the need for strict regulations on the use as well as save disposal of this group of compounds in the communities.

Keywords: organic pollutants, polychlorinated biphenyls, pollution, solvent extraction

Procedia PDF Downloads 316
3964 An Application of Fuzzy Analytical Network Process to Select a New Production Base: An AEC Perspective

Authors: Walailak Atthirawong

Abstract:

By the end of 2015, the Association of Southeast Asian Nations (ASEAN) countries proclaim to transform into the next stage of an economic era by having a single market and production base called ASEAN Economic Community (AEC). One objective of the AEC is to establish ASEAN as a single market and one production base making ASEAN highly competitive economic region and competitive with new mechanisms. As a result, it will open more opportunities to enterprises in both trade and investment, which offering a competitive market of US$ 2.6 trillion and over 622 million people. Location decision plays a key role in achieving corporate competitiveness. Hence, it may be necessary for enterprises to redesign their supply chains via enlarging a new production base which has low labor cost, high labor skill and numerous of labor available. This strategy will help companies especially for apparel industry in order to maintain a competitive position in the global market. Therefore, in this paper a generic model for location selection decision for Thai apparel industry using Fuzzy Analytical Network Process (FANP) is proposed. Myanmar, Vietnam and Cambodia are referred for alternative location decision from interviewing expert persons in this industry who have planned to enlarge their businesses in AEC countries. The contribution of this paper lies in proposing an approach model that is more practical and trustworthy to top management in making a decision on location selection.

Keywords: apparel industry, ASEAN Economic Community (AEC), Fuzzy Analytical Network Process (FANP), location decision

Procedia PDF Downloads 235
3963 Comparative Analysis of Single vs. Multiple gRNA on NGN3 Expression Using a Controllable dCas9-VP192 Activator (CRISPRa)

Authors: Nicholas Abdilmasih, Habib Rezanejad

Abstract:

This study investigates the gene expression induction efficiency of single versus multiple guide RNAs (gRNAs) targeting the NGN3 gene using the CRISPR activation system in HEK293 cells. Our study aimed to contribute to optimizing the use of gRNAs in gene therapy applications, particularly in treating diseases like diabetes, where precise gene regulation is essential. The experimental design involves culturing HEK293 cells, and once they reach approximately 70-80% confluence, cells were transfected with specific gRNAs targeting the NGN3 gene promoter. Specific gRNAs targeting the NGN3 promoter that was previously designed, incorporated into plasmid clone cassettes and introduced into HEK293 cells through co-transfection using pCAG-DDdCas9-VP192-EGFP transactivator. Post-transfection, cell viability, and fluorescence were monitored to assess transfection efficiency. RNA was extracted, converted to cDNA, and analyzed via qPCR to measure NGN3 expression levels. Results indicated that specific combinations of fewer gRNAs led to higher NGN3 activation compared to multiple gRNAs, challenging the assumption that more gRNAs result in synergistic gene activation. These findings suggest that optimized gRNA combinations can enhance gene therapy efficiency, potentially leading to more effective treatments for conditions like diabetes.

Keywords: CRISPR activation, Diabetes mellitus, gene therapy, guide RNA, Neurogenin3

Procedia PDF Downloads 23
3962 Computationally Efficient Electrochemical-Thermal Li-Ion Cell Model for Battery Management System

Authors: Sangwoo Han, Saeed Khaleghi Rahimian, Ying Liu

Abstract:

Vehicle electrification is gaining momentum, and many car manufacturers promise to deliver more electric vehicle (EV) models to consumers in the coming years. In controlling the battery pack, the battery management system (BMS) must maintain optimal battery performance while ensuring the safety of a battery pack. Tasks related to battery performance include determining state-of-charge (SOC), state-of-power (SOP), state-of-health (SOH), cell balancing, and battery charging. Safety related functions include making sure cells operate within specified, static and dynamic voltage window and temperature range, derating power, detecting faulty cells, and warning the user if necessary. The BMS often utilizes an RC circuit model to model a Li-ion cell because of its robustness and low computation cost among other benefits. Because an equivalent circuit model such as the RC model is not a physics-based model, it can never be a prognostic model to predict battery state-of-health and avoid any safety risk even before it occurs. A physics-based Li-ion cell model, on the other hand, is more capable at the expense of computation cost. To avoid the high computation cost associated with a full-order model, many researchers have demonstrated the use of a single particle model (SPM) for BMS applications. One drawback associated with the single particle modeling approach is that it forces to use the average current density in the calculation. The SPM would be appropriate for simulating drive cycles where there is insufficient time to develop a significant current distribution within an electrode. However, under a continuous or high-pulse electrical load, the model may fail to predict cell voltage or Li⁺ plating potential. To overcome this issue, a multi-particle reduced-order model is proposed here. The use of multiple particles combined with either linear or nonlinear charge-transfer reaction kinetics enables to capture current density distribution within an electrode under any type of electrical load. To maintain computational complexity like that of an SPM, governing equations are solved sequentially to minimize iterative solving processes. Furthermore, the model is validated against a full-order model implemented in COMSOL Multiphysics.

Keywords: battery management system, physics-based li-ion cell model, reduced-order model, single-particle and multi-particle model

Procedia PDF Downloads 111
3961 Fuzzy Optimization Multi-Objective Clustering Ensemble Model for Multi-Source Data Analysis

Authors: C. B. Le, V. N. Pham

Abstract:

In modern data analysis, multi-source data appears more and more in real applications. Multi-source data clustering has emerged as a important issue in the data mining and machine learning community. Different data sources provide information about different data. Therefore, multi-source data linking is essential to improve clustering performance. However, in practice multi-source data is often heterogeneous, uncertain, and large. This issue is considered a major challenge from multi-source data. Ensemble is a versatile machine learning model in which learning techniques can work in parallel, with big data. Clustering ensemble has been shown to outperform any standard clustering algorithm in terms of accuracy and robustness. However, most of the traditional clustering ensemble approaches are based on single-objective function and single-source data. This paper proposes a new clustering ensemble method for multi-source data analysis. The fuzzy optimized multi-objective clustering ensemble method is called FOMOCE. Firstly, a clustering ensemble mathematical model based on the structure of multi-objective clustering function, multi-source data, and dark knowledge is introduced. Then, rules for extracting dark knowledge from the input data, clustering algorithms, and base clusterings are designed and applied. Finally, a clustering ensemble algorithm is proposed for multi-source data analysis. The experiments were performed on the standard sample data set. The experimental results demonstrate the superior performance of the FOMOCE method compared to the existing clustering ensemble methods and multi-source clustering methods.

Keywords: clustering ensemble, multi-source, multi-objective, fuzzy clustering

Procedia PDF Downloads 189
3960 Radionuclide Contents and Exhalation Studies in Soil Samples from Sub-Mountainous Region of Jammu and Kashmir

Authors: Manpreet Kaur

Abstract:

The effect of external and internal exposure in outdoor and indoor environment can be significantly gauged by natural radionuclides. Therefore, it is a consequential to approximate the level of radionuclide contents in soil samples of any area and the risks associated with it. Rate of radon emerging from soil is also one of the prominent parameters for the assessment of radon levels in environmental. In present study, natural radionuclide contents viz. ²³²Th, ²³⁸U and ⁴⁰K and radon/thoron exhalation rates were evaluated operating thallium doped sodium iodide gamma radiation detector and advanced Smart Rn Duo technique in the soil samples from 30 villages of Jammu district, Jammu and Kashmir, India. Radon flux rate was also measured by using surface chamber technique. Results obtained with two different methods were compared to investigate the cause of emanation factor in the soil profile. The radon mass exhalation rate in the soil samples has been found varying from 15 ± 0.4 to 38 ± 0.8 mBq kg⁻¹ h⁻¹ while thoron surface exhalation rate has been found varying from 90 ± 22 to 4880 ± 280 Bq m⁻² h⁻¹. The mean value of radium equivalent activity (99 ± 27 Bq kg⁻¹) was appeared to be well within the admissible limit of 370 Bq kg⁻¹ suggested by Organization for Economic Cooperation and Development (2009) report. The values of various parameters related to radiological hazards were also calculated and all parameters have been found to be well below the safe limits given by various organizations. The outcomes pointed out that region was protected from danger as per health risks effects associated with these radionuclide contents is concerned.

Keywords: absorbed dose rate, exhalation rate, human health, radionuclide

Procedia PDF Downloads 136
3959 Prognostic and Predictive Value of Tumor: Infiltrating Lymphocytes in Triple Negative Breast Cancer

Authors: Wooseok Byon, Eunyoung Kim, Junseong Kwon, Byung Joo Song, Chan Heun Park

Abstract:

Background/Purpose: Previous preclinical and clinical data suggest that increased lymphocytic infiltration would be associated with good prognosis and benefit from immunogenic chemotherapy especially in triple-negative breast cancer (TNBC). We investigated a single-center experience of TNBC and relationship with lymphocytic infiltration. Methods: From January 2004 to December 2012, at the Department of Surgery, Kangbuk Samsung Hospital, Sungkyunkwan University, School of Medicine, we retrospectively reviewed 897 breast cancer patients-clinical outcomes, clinicopathological characteristics, breast cancer subtypes. And we reviewed lymphocytic infiltration of TNBC specimens by two pathologists. Statistical analysis of risk factors associated with recurrence was performed. Results: A total of 897 patients, 76 were TNBC (8.47%). Mean age of TNBC patients were 50.95 (SD10.42) years, mean follow-up periods was 40.06 months. We reviewed 49 slides, and there were 8 recurrent breast cancer patients (16.32%), and 4 patients were expired (8.16%). There were 9 lymphocytic predominant breast cancers (LPBC)-carcinomas with either intratumoral lymphocytes in >60% of tumor cell nests. 1 patient of LPBC was recurred and 8 were not. In multivariate logistic regression, the odds ratio of lymphocytic infiltration was 0.59 (p=0.643). Conclusion: In a single-center experience of TNBC, the lymphocytic infiltration in tumor cell nest might be a good trend on the prognosis but there was not statistically significant.

Keywords: tumor-infiltrating lymphocytes, triple negative breast cancer, medical and health sciences

Procedia PDF Downloads 407
3958 FTIR Spectroscopy for in vitro Screening in Microbial Biotechnology

Authors: V. Shapaval, N. K. Afseth, D. Tzimorotas, A. Kohler

Abstract:

Globally there is a dramatic increase in the demand for food, energy, materials and clean water since natural resources are limited. As a result, industries are looking for ways to reduce rest materials and to improve resource efficiency. Microorganisms have a high potential to be used as bio factories for the production of primary and secondary metabolites that represent high-value bio-products (enzymes, polyunsaturated fatty acids, bio-plastics, glucans, etc.). In order to find good microbial producers, to design suitable substrates from food rest materials and to optimize fermentation conditions, rapid analytical techniques for quantifying target bio products in microbial cells are needed. In the EU project FUST (R4SME, Fp7), we have developed a fully automated high-throughput FUST system based on micro-cultivation and FTIR spectroscopy that facilitates the screening of microorganisms, substrates and fermentation conditions for the optimization of the production of different high-value metabolites (single cell oils, bio plastics). The automated system allows the preparation of 100 samples per hour. Currently, The FUST system is in use for screening of filamentous fungi in order to find oleaginous strains with the ability to produce polyunsaturated fatty acids, and the optimization of cheap substrates, derived from food rest materials, and the optimization of fermentation conditions for the high yield of single cell oil.

Keywords: FTIR spectroscopy, FUST system, screening, biotechnology

Procedia PDF Downloads 443
3957 Numerical Modelling and Experiment of a Composite Single-Lap Joint Reinforced by Multifunctional Thermoplastic Composite Fastener

Authors: Wenhao Li, Shijun Guo

Abstract:

Carbon fibre reinforced composites are progressively replacing metal structures in modern civil aircraft. This is because composite materials have large potential of weight saving compared with metal. However, the achievement to date of weight saving in composite structure is far less than the theoretical potential due to many uncertainties in structural integrity and safety concern. Unlike the conventional metallic structure, composite components are bonded together along the joints where structural integrity is a major concern. To ensure the safety, metal fasteners are used to reinforce the composite bonded joints. One of the solutions for a significant weight saving of composite structure is to develop an effective technology of on-board Structural Health Monitoring (SHM) System. By monitoring the real-life stress status of composite structures during service, the safety margin set in the structure design can be reduced with confidence. It provides a means of safeguard to minimize the need for programmed inspections and allow for maintenance to be need-driven, rather than usage-driven. The aim of this paper is to develop smart composite joint. The key technology is a multifunctional thermoplastic composite fastener (MTCF). The MTCF will replace some of the existing metallic fasteners in the most concerned locations distributed over the aircraft composite structures to reinforce the joints and form an on-board SHM network system. Each of the MTCFs will work as a unit of the AU and AE technology. The proposed MTCF technology has been patented and developed by Prof. Guo in Cranfield University, UK in the past a few years. The manufactured MTCF has been successfully employed in the composite SLJ (Single-Lap Joint). In terms of the structure integrity, the hybrid SLJ reinforced by MTCF achieves 19.1% improvement in the ultimate failure strength in comparison to the bonded SLJ. By increasing the diameter or rearranging the lay-up sequence of MTCF, the hybrid SLJ reinforced by MTCF is able to achieve the equivalent ultimate strength as that reinforced by titanium fastener. The predicted ultimate strength in simulation is in good agreement with the test results. In terms of the structural health monitoring, a signal from the MTCF was measured well before the load of mechanical failure. This signal provides a warning of initial crack in the joint which could not be detected by the strain gauge until the final failure.

Keywords: composite single-lap joint, crack propagation, multifunctional composite fastener, structural health monitoring

Procedia PDF Downloads 163
3956 Fracture Toughness Characterizations of Single Edge Notch (SENB) Testing Using DIC System

Authors: Amr Mohamadien, Ali Imanpour, Sylvester Agbo, Nader Yoosef-Ghodsi, Samer Adeeb

Abstract:

The fracture toughness resistance curve (e.g., J-R curve and crack tip opening displacement (CTOD) or δ-R curve) is important in facilitating strain-based design and integrity assessment of oil and gas pipelines. This paper aims to present laboratory experimental data to characterize the fracture behavior of pipeline steel. The influential parameters associated with the fracture of API 5L X52 pipeline steel, including different initial crack sizes, were experimentally investigated for a single notch edge bend (SENB). A total of 9 small-scale specimens with different crack length to specimen depth ratios were conducted and tested using single edge notch bending (SENB). ASTM E1820 and BS7448 provide testing procedures to construct the fracture resistance curve (Load-CTOD, CTOD-R, or J-R) from test results. However, these procedures are limited by standard specimens’ dimensions, displacement gauges, and calibration curves. To overcome these limitations, this paper presents the use of small-scale specimens and a 3D-digital image correlation (DIC) system to extract the parameters required for fracture toughness estimation. Fracture resistance curve parameters in terms of crack mouth open displacement (CMOD), crack tip opening displacement (CTOD), and crack growth length (∆a) were carried out from test results by utilizing the DIC system, and an improved regression fitting resistance function (CTOD Vs. crack growth), or (J-integral Vs. crack growth) that is dependent on a variety of initial crack sizes was constructed and presented. The obtained results were compared to the available results of the classical physical measurement techniques, and acceptable matchings were observed. Moreover, a case study was implemented to estimate the maximum strain value that initiates the stable crack growth. This might be of interest to developing more accurate strain-based damage models. The results of laboratory testing in this study offer a valuable database to develop and validate damage models that are able to predict crack propagation of pipeline steel, accounting for the influential parameters associated with fracture toughness.

Keywords: fracture toughness, crack propagation in pipeline steels, CTOD-R, strain-based damage model

Procedia PDF Downloads 63
3955 Simulation and Assessment of Carbon Dioxide Separation by Piperazine Blended Solutions Using E-NRTL and Peng-Robinson Models: Study of Regeneration Heat Duty

Authors: Arash Esmaeili, Zhibang Liu, Yang Xiang, Jimmy Yun, Lei Shao

Abstract:

A high-pressure carbon dioxide (CO₂) absorption from a specific off-gas in a conventional column has been evaluated for the environmental concerns by the Aspen HYSYS simulator using a wide range of single absorbents and piperazine (PZ) blended solutions to estimate the outlet CO₂ concentration, CO₂ loading, reboiler power supply, and regeneration heat duty to choose the most efficient solution in terms of CO₂ removal and required heat duty. The property package, which is compatible with all applied solutions for the simulation in this study, estimates the properties based on the electrolyte non-random two-liquid (E-NRTL) model for electrolyte thermodynamics and Peng-Robinson equation of state for vapor phase and liquid hydrocarbon phase properties. The results of the simulation indicate that piperazine, in addition to the mixture of piperazine and monoethanolamine (MEA), demands the highest regeneration heat duty compared with other studied single and blended amine solutions, respectively. The blended amine solutions with the lowest PZ concentrations (5wt% and 10wt%) were considered and compared to reduce the cost of the process, among which the blended solution of 10wt%PZ+35wt%MDEA (methyldiethanolamine) was found as the most appropriate solution in terms of CO₂ content in the outlet gas, rich-CO₂ loading, and regeneration heat duty.

Keywords: absorption, amine solutions, aspen HYSYS, CO₂ loading, piperazine, regeneration heat duty

Procedia PDF Downloads 188
3954 Factors of Major Depressive Disorder (MDD): Prevalence of Social Support on Stress within Parental Depression

Authors: Calvin Chiu, Samar Saade Needham

Abstract:

The factors associated with the development of major depressive disorder (MDD) have been an ongoing area of concern within the field of psychopathology. Among parents, the rise in stress factors for individuals receiving less social support contributes to an increase in MDD cases. Understanding the causal aspects of MDD through the interworking of stress development within social support disparities provides critical insights into preventive measures for depressive symptoms. The present study seeks to assess the impact of social support on stress formation within MDD. Such that single parents lacking social support prompt an increase in stress formation, which proliferates the progression of MDD. Participants in this study were 450 ethnic minority mothers and fathers experiencing health inequities during pregnancy and early childhood. Perceived stress, social support, and depression are assessed by multi-item questionnaires that produce score ranges for general findings. Results indicated that lower social support scores resulted in higher depression scores, and higher perceived stress scores produced higher depression scores. Furthermore, single parents reported higher depression scores. These findings overlap with studies on paternal depression and suggest that MDD is a product of stress accumulation due to declining social support systems. Future studies may specify effective social support systems for decreasing stress accumulation in MDD formation in preventive strategies.

Keywords: major depressive disorder, stress formation, cognitive-behavioral outcomes, deficit-based behaviors

Procedia PDF Downloads 43
3953 Effects of Using Alternative Energy Sources and Technologies to Reduce Energy Consumption and Expenditure of a Single Detached House

Authors: Gul Nihal Gugul, Merih Aydinalp-Koksal

Abstract:

In this study, hourly energy consumption model of a single detached house in Ankara, Turkey is developed using ESP-r building energy simulation software. Natural gas is used for space heating, cooking, and domestic water heating in this two story 4500 square feet four-bedroom home. Hourly electricity consumption of the home is monitored by an automated meter reading system, and daily natural gas consumption is recorded by the owners during 2013. Climate data of the region and building envelope data are used to develop the model. The heating energy consumption of the house that is estimated by the ESP-r model is then compared with the actual heating demand to determine the performance of the model. Scenarios are applied to the model to determine the amount of reduction in the total energy consumption of the house. The scenarios are using photovoltaic panels to generate electricity, ground source heat pumps for space heating and solar panels for domestic hot water generation. Alternative scenarios such as improving wall and roof insulations and window glazing are also applied. These scenarios are evaluated based on annual energy, associated CO2 emissions, and fuel expenditure savings. The pay-back periods for each scenario are also calculated to determine best alternative energy source or technology option for this home to reduce annual energy use and CO2 emission.

Keywords: ESP-r, building energy simulation, residential energy saving, CO2 reduction

Procedia PDF Downloads 199
3952 Numerical and Simulation Analysis of Composite Friction Materials Using Single Plate Clutch Pad in Agricultural Tractors

Authors: Ravindra Raju, Vidhu Kampurath

Abstract:

For smooth transition of the power from the engine to the transmission system, a clutch is used. In agricultural tractors, friction clutches are widely used in power transmission applications. To transmit the maximum torque in friction clutches, selection of materials is one of the important tasks. The present used material for friction disc is Asbestos, Ceramic etc. In this study, analysis is performed using composites materials. The composite materials are considered due to their high strength to weight ratio. Composite materials like kevlar49, kevlar 29U were used in the study. The paper presents a systematic approach to optimize the structural and thermal characteristics of the clutch friction pad. A single plate clutch is modeled using Creo 2.0 software and analyzed using ANSYS. Thermal analysis considers the reduction of heat generated between the friction surfaces and reducing the temperature rise during the steady state period. Structural analysis is done to minimize the stresses developed as a result of the loading contact between friction surfaces. Also, modal analysis is done to optimize the natural frequency of the friction plate to avoid being in resonance with the engine frequency range. The analysis carried out on ANSYS workbench to get the foremost appropriate friction material for clutch. From the analyzed results stress, strain / total deformation values and natural frequency of the materials were compared for all the composite materials and the best one was taken out. For the study purpose, specifications of the clutch are obtained from the MF1035 (47KW) Tractor model.

Keywords: ANSYS, clutch, composite materials, creo

Procedia PDF Downloads 299
3951 Noise and Thermal Analyses of Memristor-Based Phase Locked Loop Integrated Circuit

Authors: Naheem Olakunle Adesina

Abstract:

The memristor is considered as one of the promising candidates for mamoelectronic engineering and applications. Owing to its high compatibility with CMOS, nanoscale size, and low power consumption, memristor has been employed in the design of commonly used circuits such as phase-locked loop (PLL). In this paper, we designed a memristor-based loop filter (LF) together with other components of PLL. Following this, we evaluated the noise-rejection feature of loop filter by comparing the noise levels of input and output signals of the filter. Our SPICE simulation results showed that memristor behaves like a linear resistor at high frequencies. The result also showed that loop filter blocks the high-frequency components from phase frequency detector so as to provide a stable control voltage to the voltage controlled oscillator (VCO). In addition, we examined the effects of temperature on the performance of the designed phase locked loop circuit. A critical temperature, where there is frequency drift of VCO as a result of variations in control voltage, is identified. In conclusion, the memristor is a suitable choice for nanoelectronic systems owing to a small area, low power consumption, dense nature, high switching speed, and endurance. The proposed memristor-based loop filter, together with other components of the phase locked loop, can be designed using memristive emulator and EDA tools in current CMOS technology and simulated.

Keywords: Fast Fourier Transform, hysteresis curve, loop filter, memristor, noise, phase locked loop, voltage controlled oscillator

Procedia PDF Downloads 186
3950 Investigation on Scattered Dose Rate and Exposure Parameters during Diagnostic Examination Done with an Overcouch X-Ray Tube in Nigerian Teaching Hospital

Authors: Gbenga Martins, Christopher J. Olowookere, Lateef Bamidele, Kehinde O. Olatunji

Abstract:

The aims of this research are to measure the scattered dose rate during an X-ray examination in an X-ray room, compare the scattered dose rate with exposure parameters based on the body region examined, and examine the X-ray examination done with an over couch tube. The research was carried out using Gamma Scout software installation on the computer system (Laptop) to record the radiation counts, pulse rate, and dose rate. The measurement was employed by placing the detector at 900 to the incident X-ray. Proforma was used for the collection of patients’ data such as age, sex, examination type, and initial diagnosis. Data such as focus skin distance (FSD), body mass index (BMI), body thickness of the patients, the beam output (kVp) were collected at Obafemi Awolowo University, Ile-Ife, Western Nigeria. Total number of 136 patients was considered during this research. Dose rate range between 14.21 and 86.78 µSv/h for the plain abdominal region, 85.70 and 2.86 µSv/h for the lumbosacral region,1.3 µSv/yr and 3.6 µSv/yr in the pelvis region, 2.71 µSv/yr and 28.88 µSv/yr for leg region, 3.06 µSv/yr and 29.98 µSv/yr in hand region. The results of this study were compared with those of other studies carried out in other countries. The findings of this study indicated that the number of exposure parameters selected for each diagnostic examination contributed to the dose rate recorded. Therefore, these results call for a quality assurance program (QAP) in diagnostic X-ray units in Nigerian hospitals.

Keywords: X-radiation, exposure parameters, dose rate, pulse rate, number of counts, tube current, tube potential, diagnostic examination, scattered radiation

Procedia PDF Downloads 116
3949 Reduction of False Positives in Head-Shoulder Detection Based on Multi-Part Color Segmentation

Authors: Lae-Jeong Park

Abstract:

The paper presents a method that utilizes figure-ground color segmentation to extract effective global feature in terms of false positive reduction in the head-shoulder detection. Conventional detectors that rely on local features such as HOG due to real-time operation suffer from false positives. Color cue in an input image provides salient information on a global characteristic which is necessary to alleviate the false positives of the local feature based detectors. An effective approach that uses figure-ground color segmentation has been presented in an effort to reduce the false positives in object detection. In this paper, an extended version of the approach is presented that adopts separate multipart foregrounds instead of a single prior foreground and performs the figure-ground color segmentation with each of the foregrounds. The multipart foregrounds include the parts of the head-shoulder shape and additional auxiliary foregrounds being optimized by a search algorithm. A classifier is constructed with the feature that consists of a set of the multiple resulting segmentations. Experimental results show that the presented method can discriminate more false positive than the single prior shape-based classifier as well as detectors with the local features. The improvement is possible because the presented approach can reduce the false positives that have the same colors in the head and shoulder foregrounds.

Keywords: pedestrian detection, color segmentation, false positive, feature extraction

Procedia PDF Downloads 281