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Addressed to the $N-k_{1}-k_{2}$ cascading outages, it is computationally burdensome for the reliable calculation of active and reactive power flows. This paper builds a comprehensive framework with three algorithms, including the distribution factor (DF), the Newton-Raphson (NR), and the first iteration of NR algorithm (termed as 1J). Classifiers are designed to determine whether the NR algorithm should be employed for accuracy. Classifier features are extracted upon the analytical error of 1J. As reactive power is partially considered in the 1J but neglected in the DF algorithm, the deviation between the solutions is taken as one crucial feature. The support vector machine (SVM) is then utilized for classifier training. As the deep integration of the causal inference and the statistical paradigm, this framework calculates active and reactive power flows rapidly, reliably, and robustly. The effectiveness and robustness are fully validated in three typical IEEE systems.

The quality of similar sample data determines the accuracy of photovoltaic (PV) power forecasting. However, under different time and space scales, the main meteorological characteristics affecting PV power and their mechanisms are different, which seriously affects the quality of similar samples. An adaptive classification strategy is proposed to filter historical similar samples. Firstly, path analysis (PA) adaptation is utilized to determine the main meteorological characteristics affecting PV power at different spatial and temporal scales, as well as the determining coefficient of each meteorological characteristic on PV power. Secondly, a negative feedback strategy based on the distribution factor and fitness function value of the forecasting model is claimed, which can adaptive adjust the selection time range of the historical similar samples until the forecasting model with higher fitting degree obtained based on the hybrid optimization support vector regression (HO-SVR) algorithm training. Finally, the validity and practicability of the forecasting model are verified by historical measured meteorological data and power data of a PV power plant.

The current study is aimed to estimate the diagnostic reference dose levels (DRLs), the volume computer tomogram dose index (CTDIvol), the CT air kerma-length product (PKL,CT) and the effective dose (E) for head, chest and chest-abdomen-pelvic CT examinations performed on adults in King Abdullah Medical City (KAMC), Saudi Arabia. Demographic parameters (such as age, gender, weight, height) for a sample of 535 computed tomography (CT) patients and physical scan parameters (such as patient tube voltage (kV), reference and effective mill ampere-second (mAs), scan length, number of slices, and pitch factor) were collected from a picture archiving and communication system (PACS). CTDIvol and PKL,CT were studied for different patients weights (40 -60 kg, 60-80 kg, 80-100 kg and 100-120 kg). Mean CTDIvol, PKL,CT and effective dose for a standard weight (70 kg ±10%) was evaluated according to the three CT protocols considered and the results were, as follows: for head examinations – 61.8 mGy, 1212 mGy.cm and 2.55 mSv, respectively; for chest examinations- 13.1 mGy, 657.5 mGy.cm and 9.21 mSv, respectively; for chest-abdomen-pelvic examinations - 13.9 mGy, 782.5 mGy.cm and 11.73 mSv, respectively. The effective dose for the chest examinations was lower than the corresponding value communicated by the European study group under European Commission. The effective dose for head examinations, was slightly higher than the one communicated by the European Commission study due to differences in the scan length. It needs optimizing the radiation dose delivered to patients via periodical review of scan parameters for a protocol under study.

A live-load test was conducted on an in-service bridge containing flat precast concrete slabs. The purpose of the test was to evaluate transverse load distribution and efficiency of the lon...

The existing studies have shown that parapets have great influence on the girder distribution factor (GDF) of bridges. However, there is no method in the design guide to estimate the GDF considering the effect of parapets. This research aims to develop a simplified method for estimating the GDF by considering the effect of parapets. First, a simply supported steel-concrete composite girder bridge was tested to investigate the effect of parapets on the GDF. Then, finite-element (FE) model was established and verified by the field test data of strain and deflection. In addition, error study showed that the bending stiffness of the bridge was increased by about 92% and 19.1%, respectively, due to the effects of parapet and continuous layer. As the effect of the continuous layer on each girder was relatively uniform, the simplified method was optimized only considering the effect of the parapet. Finally, the effect of the parapet on the GDF was compared and discussed. Considering the effect of the parapet, the GDF of the exterior girder calculated by the simplified method and FE analysis decreased by about 26.92% and 23.53%, respectively, and the adjacent interior girder decreased by about 15.22% and 12.77%, respectively. Comparing the GDF calculated by the AASHTO LRFD specifications, the GDF calculated by the simplified method decreased by about 30.77% in the exterior girder and 41.30% in the interior girder, respectively. The results indicate that the method of calculating the GDF without considering the effect of the parapet in AASHTO LRFD specifications is conservative. The GDF calculated by the simplified method was basically close to the field test results, meaning that the proposed simplified method considering the effect of the parapet was relatively accurate.

A series of 3D finite element (FE) analyses were performed to estimate the peak penetration resistance of spudcan foundations in sand over clay soil profiles. Elasto-perfectly plastic models following Mohr&ndash, Coulomb and Tresca failure criteria were used for sand and clay layers, respectively. The coupled Eulerian&ndash, Lagrangian (CEL) approach was used to simulate the large deformation in soil that occurs during the spudcan penetration. The performance of the numerical model was validated against centrifuge test results. A parametric study with a broad range of strength parameters for sand and clay was performed. The numerical results were used to assess the influence of sand thickness (Hs), the diameter of spudcan (D), friction angle of sand, and undrained shear strength of clay (su). A wide range of su was utilized to predict the resistance both of the soft and stiff clays. The calculated peak resistances are compared with a published analytical model. It is demonstrated that the model highly overestimates the peak resistance for stiff clays, most likely because it was developed specifically for soft clays and, therefore, does not account for the influence of su. One of the parameters of the model is revised to account both for su. Comparisons highlight that the modified model is able to capture the simulated peak penetration resistance for both soft and stiff clays.

Live load tests were conducted on an in-service bridge containing decked Northeast Extreme Tee (NEXT-D) girders. The purpose of the tests was to evaluate transverse load distribution and to...

The use of mineral fillers in the paper industry has attracted much attention due to its low cost and ability to improve optical properties and printability. Besides the filler characteristics, paper properties, such as bulk, tensile, and opacity, are greatly affected by filler distribution in the z-direction. Therefore, optimization of filler distribution is an effective way to maximize the value of fillers. In this work, a filler distribution factor (Fc) was proposed to quantitatively describe the concentrated degree of filler distribution in the z-direction. The reduction in Fc resulted in an increase in paper bulk, porosity, and opacity, due to the generation of more interfaces between fibers and fillers. When filler particles were concentrated in one layer (Fc = 1), the tensile strength of the filled paper increased between 26 to 40% in comparison to the paper with various Fc values. For a given Fc, better tensile and opacity properties were achieved by increasing filler concentration on the surface layer of paper.

Maintenance of bridges in use is essential and measuring the live load distribution factor (LLDF) of a bridge to examine bridge integrity and safety is important. A vehicle loading test has been used to measure the LLDF of a bridge. To carry this out on a bridge in use, traffic control is required because loading must be performed at designated positions using vehicles whose details are known. This makes it difficult to measure LLDF. This study proposed a method of estimating the LLDF of a bridge using the vertical displacement response caused by traveling vehicles under ambient vibration conditions in the absence of vehicle control. Since the displacement response measured from a bridge included both static and dynamic components, the static component required for the estimation of LLDF was extracted using empirical mode decomposition (EMD). The vehicle loading and ambient vibration tests were conducted to verify the validity of the proposed method. It was confirmed that the proposed method can effectively estimate the LLDF of a bridge if the vehicle type and driving lane on the bridge are identified in the ambient vibration test.

Contents of As, Cd, Co, Cr, Cu, Ni, Pb and Zn were determined in the material collected in sandboxes of seven spa resorts located in S Poland (CCE) and their results used to establish a health risk of children. After sieving out grains > 2 mm, the bulk samples were quantitatively separated into four grain fractions: 2000–1000, 1000–200, 200–63 and

The characteristics of hot particles in the ambient environment are presented: activity, propagation, size, and density as well as contribution to the total activity of contaminants, distribution factor, leach rate, and deposition rate. The differences of suspensions, bottom deposits, and hot particles are shown. The equations governing the transport of radionuclides are formulated for systems, consisting of hot particles and suspensions, in water and bottom deposits. The coefficients in the equations are determined and the possibility of radionuclides being removed from bays by tides is taken into account. Solutions are obtained for the transport equations and the average sizes of the activity spots owing to hot particles and ordinary suspensions are determined. The possibility of transport of hot particles over large distances in a river floodplain is examined. The water circulation rate at which hot particles are carried out of flooded objects is determined.

This article describes a method of identifying combustion chamber temperature field ripple by the preparation of the set of nozzles in the engine. It shows combustion chamber temperature field ripple with a divergent nozzle and a convergent one used in the burner. The design of the combustion chamber and that of the burners are described. Diagrams are plotted that show variation in circular and radial temperature field ripple depending on the engine behavior. The combustor exit temperature field non-uniformity is assessed using such parameters as the overall temperature distribution factor, the radial temperature distribution factor and the circumferential temperature distribution factor. Comparative analysis of the results of testing two combustion chambers with different modifications of burners is carried out. Conclusions about the effect of the burner design on the temperature field ripple are made.

This paper presents a static network equivalent model for Korean power systems. The proposed equivalent model preserves the overall transmission network characteristics focusing on power flows among areas in Korean power systems. For developing the model, a power transfer distribution factor (PTDF)-based k-means++ algorithm was used to cluster the bus groups in which similar PTDF characteristics were identified. For the reduction process, the bus groups were replaced by a single bus with a generator or load, and an equivalent transmission line was determined to maintain power flows in the original system model. Appropriate voltage levels were selected, and compensation for real power line losses was made for the correct representation. A Korean power system with more than 1600 buses was reduced to a 38-bus system with 13 generators, 25 loads, and 74 transmission lines. The effectiveness of the developed equivalent model was evaluated by performing power flow simulations and comparisons of various characteristics of the original and reduced systems. The simulation comparisons show that the developed equivalent model maintains inter-area power flows as close as possible to the original Korean power systems.

To study solute distribution at the solid–liquid (S–L) interface during melt crystallization, we examined the applicability of the interfacial solute distribution factor proposed based on a kinetic model involving both mass and heat balances at the interface. The factor derived from the model was compared with the experimental results obtained by employing a binary melt with the different species and concentrations of fatty acids as biodiesel related mixtures. As a result, we were able to reveal the empirical relation between the purity of the crystal and the solidification conditions of the melt. Based on the model, we also numerically calculated the transient changes in the interfacial solute distribution factor as well as the temperature of the S–L interface in the solidification process of the melt. The minimization of the factor was confirmed when the melt was supercooled at the S–L interface after starting solidification.

Purpose: To analyse the temporal resolution (TR) of modern computed tomography (CT) scanners using the impulse method, and assess the actual maximum TR at respective helical acquisition modes. Methods: To assess the actual TR of helical acquisition modes of a 128-slice dual source CT (DSCT) scanner and a 320-row area detector CT (ADCT) scanner, we assessed the TRs of various acquisition combinations of a pitch factor (P) and gantry rotation time (R). Results: The TR of the helical acquisition modes for the 128-slice DSCT scanner continuously improved with a shorter gantry rotation time and greater pitch factor. However, for the 320-row ADCT scanner, the TR with a pitch factor of 1.0, it was approximately one half of the gantry rotation time. The maximum TR values of single- and dual-source helical acquisition modes for the 128-slice DSCT scanner were 0.138 (R/. P = 0.285/1.5) and 0.074. s (R/. P = 0.285/3.2), and the maximum TR values of the 64. ×. 0.5- and 160. ×. 0.5-mm detector configurations of the helical acquisition modes for the 320-row ADCT scanner were 0.120 (R/. P = 0.275/1.375) and 0.195. s (R/. P = 0.3/0.6), respectively. Conclusion: Because the TR of a CT scanner is not accurately depicted in the specifications of the individual scanner, appropriate acquisition conditions should be determined based on the actual TR measurement. © 2016 Associazione Italiana di Fisica Medica.

Cilj: Cilj ovog istraživanja je utvrditi utječe li se promjenom veličine pitch faktora kod CT uređaja na kvalitetu CT snimanja. Hipoteza istraživanja: Povećanjem pitch faktora ne utječemo na kvalitetu CT snimanja. Uzorak ispitanika i metode: Uporabom sintakse ključnih riječi te pretraživanjem literature pronašli smo 170 potencijalno relevantnih članaka. Nakon primjene isključnih i uključnih kriterija pregledali smo cjelovite tekstove 39 članaka, od kojih je 20 na koncu uključeno u analizu našeg istraživanja, jer su odgovarale postavljenim kriterijima kvalitete slike i doze zračenja u odnosu na pitch faktor. Rezultati: Od 11 studija koje su uspoređivale low pitch MSCT i high pitch DSCT, u 8 studija (72,7%) dobiveno je da je subjektivna kvaliteta slike ista. U 3 studije (27,3%) dobiveno je da je subjektivno kvaliteta slike manja s low pitch MSCT-om nego s high pitch DSCT-om. U svih jedanaest studija koje su uspoređivale low pitch MSCT i high pitch DSCT kod high pitch DSCT-a upotrebljavana je manja doza zračenja, a kod low pitch MSCT-a veća doza zračenja Tri rada uspoređivala su samo low i high pitch kod MSCT uređaja. U sva tri rada pronađeno je da je subjektivna kvaliteta slike jednaka, bez obzira na to koristi li se low ili high pitch. Pri korištenju low pitch MSCT-a za postizanje jednake kvalitete slike kao na high pitch MSCT-u korištene su više doze zračenja u sva tri slučaja. U ukupno 6 radova koji su uspoređivali subjektivnu kvalitetu snimke low pitch DSCT-a i high pitch DSCT-a, u tri studije pronađeno je da je kvaliteta snimke ista, a u tri slučaja da je kvaliteta slike manja s low pitch DSCT-om. Međutim, u svih 6 slučajeva low pitch DSCT-a korištene su veće doze zračenja u odnosu na high pitch DSCT kako bi se postigla bolja subjektivna kvaliteta slike u tih 50% studija. Zaključak: Ovim istraživanjem nije dokazano kako postoji statistički značajan utjecaj pitch faktora na kvalitetu slike kod višeslojnih CT uređaja, ali je potvrđeno kako high pitch faktor značajno utječe na smanjenje doze zračenja bolesnika. Objective: The objective of this study is to determine how with changing the size of pitch factor at CT device we can affect the CT recording quality. Hypothesis of research: By increasing the pitch factor we do not affect the CT recording quality. Sample of examinees and methods: By using keywords syntax and searching the literature we found 170 potentially relevant articles. Following the application of the exclusion and inclusion criteria, we reviewed the complete texts of 39 articles, of which 20 were finally included in the analysis of our research, because they corresponded to the established image quality criteria and radiation dose in relation to the pitch factor. Results: Of 11 studies which compared low pitch MSCT and high pitch DSCT, in 8 studies (72.7%) it was found that the subjective image quality is the same. In 3 studies (27.3%), subjective image quality was lower with low pitch MSCT than with high pitch DSCT. In all eleven studies which compared low pitch MSCT and high pitch DSCT, at high pitch DSCT a lower radiation dose was used and at low pitch MSCT a higher dose of radiation was used. Three papers compared only low and high pitch at MSCT devices. In all three papers, subjective image quality was found to be equal regardless of whether low or high pitch was used. When using low pitch MSCT to achieve the same image quality as at high pitch MSCT, higher radiation doses were used in all three cases. In a total of 6 papers which compared the subjective quality of low pitch DSCT and high pitch DSCT, in three studies it was found that the image quality is the same, and in three cases the image quality was lower with low pitch DSCT. However, in all 6 cases of low pitch DSCT, higher radiation doses were used compared to high pitch DSCT in order to achieve better subjective image quality in 50% of these studies. Conclusion: This research did not find that there was a statistically significant influence of pitch factor on the image quality at multilayer CT devices, but we have confirmed that high pitch factor significantly affects the reduction of radiation dose of patients.

This paper proposes a modification of distribution factor methods for identifying the load contribute in a transmission open access, with regard to the load power factor. This method may be considered as the first pricing strategy to be proposed in bilateral transaction for transmission usage, based on the actual use of the transmission network. The merit of this method relies on the existence of a load power factor with GLDF methods, which allocate the transmission cost, not only based on the amount of power flow but also on the load characteristic. A case study utilizing the IEEE 30-bus system was conducted to illustrate the contribution of the proposed method in allocating the transmission usage to the user in a fair manner.

The purpose of this study was to evaluate the performance of active collimator by changing acquisition parameters and obtaining dose profiles in z-axis direction. Dose profiles along z-axis were obtained using XRQA2 Gafchromic film. As a result, the active collimator reduced overranging about 55% compared to that without the active collimator. In addition, by changing the combination of X-ray beam width (32 mm, 40 mm), pitch factor (1.4, 0.6), and the X-ray tube rotation time (0.5 s/rot, 1.0 s/rot), the overranging changed from 19.4 to 34.9 mm. Although the active collimator is effective for reducing overranging, it is necessary to adjust acquisition parameters by taking the properties of the active collimator for acquisition parameters, especially setting beam width, into consideration.

Multilayered structures are widely used in housing construction, shipbuilding, aviation and space-rocket engineering. In designing such structures it is necessary to estimate their sound insulation capacity for the forecasting of levels of noise taking place in this or that premise or compartment. The paper presents a methodology of calculating sound insulation of a multilayered structure developed on the basis of solving wave equations in each of the layers taking into account the incident angle of sound waves and losses in layers; introduction of boundary conditions establishing equality on the borders of media of normal oscillatory speeds and acoustic pressure; drawing up a system of algebraic complex equations and a matrix equation corresponding to them; drawing up an inverse matrix of factors at functions of acoustic pressure. Examples of calculating factors of sound insulation for multilayered structures with various parameters are presented (superficial weights, thickness of layers, various incident angles). A graphic comparison of the results of calculations using the methods of inverse matrix and the impedance method as well as a graphic comparison of results of flight-design measurements (FDM) of the sound insulation of a regular head part, consisting of layers of coal tape, fiber glass fabrics, aluminum honeycombs and a layer of polyurethane foam are given. The results of calculation using the inverse matrix method are given and the advantage of the method is emphasized.

In this paper, the modified live-load and designed formula are studied according to the fact the highway bridge design specifications are recently revised. The two examples for composite steel plates and PSC girder bridges are studied. The envelope is analyzed with the finite element models and lateral load distribution method applying the existing highway bridge specification(2010), the newly revised highway bridge specification(2015) and AASHTO LRFD. In case of composite steel plates, length changes between spans are studied, and in case of PSC girder. changes of the number of cross-beams and spans, and span-lengths, are analyzed. Keywords :Live load, plane grillage model, lateral distribution factor method, finite element method † Corresponding author: Tel: +82-31-290-7514; E-mail: kmye@skku.ac.kr Received October 17 2014; Revised January 21 2015Accepted February 23 2015Ⓒ2015 by Computational Structural Engineering Institute of KoreaThis is an Open-Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License(http://creativecommons. org/licenses/by-nc/3.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

In this paper, we explore the links between polygyny and female labour supply in Senegal using a nationally representative survey. In a reduced-form approach, we first measure the impact of polygyny on participation using a joint model of spouse participation. The identification of the impact of polygyny relies on the use of district-level variables as instruments. We find a positive impact of polygyny on female labour force participation. Turning to a structural approach based on the collective household model, we examine the possibility that men within couples use polygyny as a threat to influence the distribution of resources in their favour. The results are less conclusive regarding the role played by the risk of polygyny as an effective distribution factor.

Aims and objectives Methods and materials Results Conclusion Personal information References, Aims and objectives: Different parameters on CT can be used to reduce the patient radiation dose. One of these parameters is pitch, which is defined as the table movement per 360 degrees rotation time divided by the beam width (1). The use of a high pitch can reduce the...

The purpose of this study was aimed to evaluate the symmetrical effect of pitch factor to SNR (Signal to Noise Ratio) in thorax phantom CT images. Thorax CT phantom was designed to contain cork and cylindrical objects with several sizes located symmetrically respect to Y-axis. Phantom size is 20 cm diameter, 22 cm length, and the objects simulated vessels filled with contrast medium (diameter A: 2mm, B: 1.7 mm, C: 1 mm, respectively). The distance between two objects: A: 6 cm, B: 8 cm, and C: 12 cm. Image acquisitions were performed:130 kVp, tube rotation 0.6s, 70 mAs, and pitch values were 0.5, 0.8, 1.0, 1.5, 1.8 and 2.0. CT images represented by 9 axial images with a slice thickness of 5 mm. The difference of SNRs (Δ): a value of ΔA, in general high at initial slice and fall significantly up to the third slice and then followed by a nearly constant value. ΔB at initial slice trend decreased with increasing slice images. ΔC at all pitch initially shown zero value and increase to maximum up to second slice (not more than 20 units) and tend to constant after at sixth slice. Effect of all pitch values on symmetrical object images was influenced by the distance between two corresponding objects and slice order. Generally at the initial slice, the SNR difference between two corresponding objects (Δ) relatively high compared with the following order slice. Therefore, in clinical practice, it is recommended to give additional FOV at least 1.5 cm at the initial slice interest.

Background and aimThis study proposed a method to estimate the beam-on time for prostate cancer patients treated on Tomotherapy when FW (field width), PF (pitch factor), modulation factor (MF) and treatment length (TL) were given.Material and methodsThe study was divided into two parts: building and verifying the model. To build a model, 160 treatment plans were created for 10 patients. The plans differed in combination of FW, PF and MF. For all plans a graph of beam-on time as a function of TL was created and a linear trend function was fitted. Equation for each trend line was determined and used in a correlation model. Finally, 62 plans verified the treatment time computation model – the real execution time was compared with our estimation and irradiation time calculated based on the equation provided by the manufacturer.ResultsA linear trend function was drawn and the coefficient of determination R2 and the Pearson correlation coefficient r were calculated for each of the 8 trend lines corresponding to the adequate treatment plan. An equation to correct the model was determined to estimate more accurately the beam-on time for different MFs. From 62 verification treatment plans, only 5 disagreed by more than 60s with the real time from the HT software. Whereas, for the equation provided by the manufacturer the discrepancy was observed in 16 cases.ConclusionsOur study showed that the model can well predict the treatment time for a given TL, MF, FW and it can be used in clinical practice.

We investigate numerically that a finite Airy-Gaussian (AiG) beam varies its trajectory and shape in the defected photonic lattices. The propagation properties and beam self-bending are controlled with modulation depth and period of the photonic lattices, positive and negative defects, beam distribution factor and nonlinearity change. For positive defects, the pseudo-period oscillation and localization of the AiG beam may be formed under a certain condition, while the beam is diffused for negative defects. Moreover, the solitons may appear during the propagation process when the self-focusing nonlinearity is introduced., 15 pages, 8 figures

This paper contributes to the understanding of gender aspects in the intra-household sharing of income. I estimate models of differences in financial satisfaction between household partners using panel data from the German Socio-Economic Panel Study, which allows one to account for household-level fixed effects. The paper adds to the literature a further convincing rejection of the equal sharing hypothesis. What is more and novel, the results imply that unequal income sharing is asymmetric and triggered by the relative employment statuses of the partners: in male breadwinner households, the women’s well-being is affected by the distribution factor; in double full-time couples, it is the man’s well-being.

The Government had devised legislation of Special Act and drew up guidelines for improving air quality in Seoul Metropolitan area. In 2007 local government of Seoul, Incheon and Gyeonggi conducted the results of application policy by reduced air pollutants emission for the first time. Although there was reduction of air pollutant emission in each local government, it was ineffective as expected using air pollution monitoring database. Therefore we worked out a way to prepare modeling input data using the results of enforcement plan. And we simulated surface and PM10 before and after decrease in air pollutants emission and examine reduction effects of air pollution according to enforcement regulation except other influence, by using MM5-SMOKE-CMAQ system. Each local government calculated the amount of emission reduction under application policy, and we developed to prepare input data so as to apply to SMOKE system using emission reduction of enforcement plan. Distribution factor of emission reduction were classified into detailed source and fuel codes using code mapping method in order to allocate the decreased emission. The code mapping method also included a way to allocate spatial distribution by CAPSS distribution. According to predicted result using the reduction of NOx emission, concentration was decreased from 19.1 ppb to 18.0 ppb in Seoul. In Gyeonggi and Incheon concentrations were down to 0.65 ppb and 0.68 ppb after application of enforcement plan. PM10 concentration was reduced from 18.2 to 17.5 in Seoul. In Gyeonggi PM10 concentration was down to 0.51 and in Incheon PM10 concentration was decreased about 0.47 which was the lower concentration than any other cities.

SUMMARY Wavelets have been used extensively in the recent past. The work presented uses multiwavelet because of its inherent property to resolve the signal better than all single wavelets. Multiwavelets are based on more than one scaling function. The resolution is better compared to Daubechies (D4) and hence the event can be detected from lesser number of samples as compared to Daubechies (D4). The proposed methodology utilizes an enhanced resolving capability of multiwavelet to recognize power system disturbances. Dempster–Shafer (DS), an intelligent classifier, has been implemented and tested for various PQ events. Two sub-classifiers, heuristic classifier and statistical classifier (χ2 distribution), have been used to support and strengthen the structural identification and temporal distribution factor of DS classifier. Results on various PQ events, such as voltage sag, voltage swell, outage, interruption, impulsive-transient (IT), oscillatory-transient (OT), noise, and notching, show that multiwavelets can detect and classify different PQ events efficiently and consistently. Copyright © 2011 John Wiley & Sons, Ltd.

A commercially available electromagnetic simulator — MAGIC, a particle-in-cell (PIC) code — has been used to carry out a comparative study of the beam-wave interaction under uniform and tapered magnetic field profiles of a 42 GHz, 200 kW gyrotron. The magnetic field profile across the resonant cavity varies by ±6.5% with a peak value of 1.615 T. The MAGIC simulation shows the desire performance of the gyrotron under both magnetic field conditions with an operating mode TE03 and a pitch factor of 1.26. The analysis of the simulated results show that stability in the power growth was reached more quickly and achieved higher output power in the case of a tapered magnetic field.

A relation of diffusion and seepage is discussed on the basis of mass conservation law for porous media saturated with a multi-component solution. Note that both phenomena have independently treated in the classical theory of porous materials. In the seepage problem we shed light on a physical implication of seepage velocity. In the diffusion problem we show sorption can be introduced on concepts of a source term, a distribution factor or an equation of adsorption isotherm.

Rationale and Objectives The latest multislice computed tomography (MSCT) scanners permit the chest and abdomen to be scanned continuously. However, conventionally, it has been necessary to perform scanning twice using different pitch factors for the cardiac and abdominal regions. We have developed a new scanning technique known as variable pitch factor scanning, in which the table speed is changed during scanning to obtain continuous images from the heart to the abdomen in a single scan, and have evaluated its physical characteristics. Materials and Methods A bead phantom, a comb phantom, and a gold wire placed at an angle were scanned using a 64-row MSCT scanner. The variation in the spatial resolution and continuity of images in the body axis direction because of changes in the pitch factor were evaluated. Results Because reconstruction taking the cone angle into consideration was employed, the spatial resolution in the body axis direction was unchanged and the continuity of images in the body axis direction was maintained at a certain level even when the pitch factor was changed. Conclusion Variable pitch factor scanning is a useful technique for obtaining continuous images from the heart to the abdomen in a single scan.

Based on mass conservation law a coupled scheme of diffusion and seepage is given for porous media saturated with a multi-component solution. Note that both phenomena have independently treated in the classical theory of porous materials. In the seepage problem we shed light on a physical implication of seepage velocity. In the diffusion problem we show sorption can be introduced on concepts of a source term, a distribution factor or an equation of adsorption isotherm. A practical procedure to evaluate diffusion coefficient is also shown.

Following a request from the European Food Safety Authority, the Panel on Plant Protection Products and their Residues developed an opinion on the science to support the development of a risk assessment scheme of plant protection products for non-target arthropods. The current risk assessment scheme is reviewed, taking into consideration recent workshops and progress in science. Proposals are made for specific protection goals which aim to protect important ecosystem services such as food web support, pest control and biodiversity. In order to address recovery and source–sink population dynamics, conducting a landscape-level risk assessment is suggested. A new risk assessment scheme is suggested which integrates modelling approaches. The main exposure routes for non-target arthropods are identified and proposals are made on how to integrate them in the risk assessment. The appropriateness of the currently used vegetation distribution factor was investigated. It is proposed that new tests be included in order to address exposure via oral uptake of residues and uncertainties related to differences in species sensitivity.

Pierre Gy's equation is widely used in ore sampling. This equation is based in four parameters: shape factor, size distribution factor, mineralogical factor and liberation factor. The usual practice is to consider fixed values for the shape and size distribution factors. This practice does not represent well several important ores. The mineralogical factor considers only one specie of interest and the gangue, leaving out other cases such as polymetalic ores where there are more than one specie of interest. A sensibility analysis to the Gy's equation factors was done and a procedure to determine specific values for them was developed and presented in this work. Mean ore characteristics, associated with an insecure use of the actual procedure, were determined. Finally, for a case study, the effects of using each alternative were evaluated.La ecuación de Pierre Gy es la más utilizada en el muestreo de minerales. Esta ecuación está basada en cuatro parámetros: factor de forma, factor de granulometría, factor de mineralogía y factor de liberación. La práctica usual es considerar valores fijos para los factores de forma y granulometría, dejando fuera a una gama importante de minerales que no son bien representados por dichos valores. Con respecto al factor de mineralogía, se consideran, solamente, una especie mineralógica de interés y la ganga, no considerando otros casos, como los minerales polimetálicos donde hay más de una especie de interés. En este trabajo se sensibilizó la ecuación de Gy con respecto a sus factores y se han desarrollado algunos procedimientos para determinar valores específicos para éstos. Se han determinado las características principales de los minerales asociadas con un uso inseguro del procedimiento utilizado actualmente. Finalmente, para un caso en estudio, se evaluó el efecto de utilizar una u otra alternativa.

The Route 601 Bridge in Sugar Grove, Virginia, spans 11.89 m (39 ft) over Dickey Creek. The bridge is the first to use the Strongwell 91.4 cm (36 in.) deep fiber-reinforced polymer double web beam in a vehicular bridge superstructure. Construction of the new bridge was completed in October 2001 and field testing was undertaken shortly thereafter, as well as in June of 2002, to assess any potential changes in structural performance. This paper details the field evaluation of the Route 601 Bridge. Using midspan deflection and strain data from the October 2001 and June 2002 field tests, AASHTO bridge design parameters were determined—namely, wheel load distribution factor g , dynamic load allowance IM , and maximum deflection. The wheel load distribution factor was determined to be S∕4 , a dynamic load allowance was determined to be 0.36, and the maximum deflection of the bridge was L∕1,110 . Deflection results were lower than the AASHTO L∕800 limit. This discrepancy is attributed to partial composite action...

Expressions were developed to estimate the cross-flow error that occurs in the one-dimensional velocity spectra determined by applying Taylor’s frozen field hypothesis to measurements with single- and cross-wire probes. The cross-flow error and the error caused by the unsteady convection of the small-scale motions were evaluated for typical measurements. It was found that the cross-flow error could be significant in inertial range of the measured one-dimensional spectra, and was much larger than the error caused by the unsteady convection of the small-scale motions in the one-dimensional spectra of the cross-stream velocity components, % MathType!Translator!2!1!AMS LaTeX.tdl!TeX -- AMS-LaTeX!

A Taiwan test standard was established in 1989 using outdoor daily efficiency test methods. This test standard has been implemented for 12 years with satisfactory results. However, it was also found from field applications that the pattern of solar irradiation would affect the result of the performance test. In the present study, we used a distribution factor Ri defined as the ratio of the total irradiation in the morning to that in the afternoon to characterize this effect. Ri reflects the asymmetry of solar irradiation distribution in the morning and afternoon. A field study was carried out. The data collected from the daily efficiency tests were screened using the criterion of 0.5≤Ri≤1.6, in addition to the conditions defined in the Taiwan test standard. Two commercial products separately located in latitude 23° N and 25° N were tested. Data scattering occurs without using the Ri criterion. If we adopt test data using Ri, the results turn out to have a much better data correlation coefficient, from 0.915 to 0.969. The system characteristic efficiency ηs* changes significantly, from 0.479 to 0.514. There is a regulation that the commercial product should have a value of ηs* exceeding 0.5 in order to obtain a subsidy from the government in Taiwan. The performance test using the old standard is shown to result in a significant error, suggesting modification of the former test standard.

An investigation into the application of the distribution factor concept, for correlating thermal conductivity data for fruits and vegetables, has been conducted. It has been found that, despite the distribution factor has a sound physical insight, its application is hindered by the empirical correlations like the porosity as a function of water content over wide range which need to be very accurate for the material of concern. It shows the necessity of generating accurate data on these relationships through careful experimentation to enable the establishment of a more sensible fundamental model. However, these would be very tedious and expensive tasks. In the mean time, the previous empirical models may be used to estimate the conductivity values.

A study using field test results was conducted to determine the effect of live load for the slab-and-beam bridge structures. From the field testing of four existing bridge structures under the real truck loading, the live load distribution factors (DFs) are deducted from the measured strain gauge values and then determined by using several methods developed by the study team. The final results for each bridge are compared against some of the previously developed methods and design codes. The distribution factor concluded from testing results should be showing lower bound values. Results are given in tabulated forms and conclusions about the distribution factors for each bridge are reached from these tables.

Helical TomoTherapy(HT) planning depends on optimize parameters including field width (FW), pitch factor (PF) and modulation factor (MF). These optimize parameters are effect to quality of plans and treatment time. The aim of this study was to find the optimized parameters which compromise between plan quality and treatment times. Six nasopharyngeal cancer patients were used. For each patient data set, 18 treatment plans consisted of different optimize parameters combination (FW=5.0, 2.5, 1.0 cm; PF=0.43, 0.287, 0.215; MF2.0, 3.0) were created. The identical optimization procedure followed ICRU83 recommendations. The average D50 of both parotid glands and treatment times per fraction were compared for all plans. The study show treatment plan with FW1.0 cm showed the lowest average D50 of both parotid glands. The treatment time increased inversely to FW. The FW1.0 cm the average treatment time was 4 times longer than FW5.0 cm. PF was very little influence on the average D50 of both parotid glands. Finally, MF increased from 2.0 to 3.0 the average D50 of both parotid glands was slightly decreased. However, the average treatment time was increased 22.28%. For routine nasopharyngeal cancer patients with HT, we suggest the planning optimization parameters consist of FW=5.0 cm, PF=0.43 and MF=2.0.