Ideal flood field images for SPECT uniformity correction
International Nuclear Information System (INIS)
Oppenheim, B.E.; Appledorn, C.R.
1984-01-01
Since as little as 2.5% camera non-uniformity can cause disturbing artifacts in SPECT imaging, the ideal flood field images for uniformity correction would be made with the collimator in place using a perfectly uniform sheet source. While such a source is not realizable the equivalent images can be generated by mapping the activity distribution of a Co-57 sheet source and correcting subsequent images of the source with this mapping. Mapping is accomplished by analyzing equal-time images of the source made in multiple precisely determined positions. The ratio of counts detected in the same region of two images is a measure of the ratio of the activities of the two portions of the source imaged in that region. The activity distribution in the sheet source is determined from a set of such ratios. The more source positions imaged in a given time, the more accurate the source mapping, according to results of a computer simulation. A 1.9 mCi Co-57 sheet source was shifted by 12 mm increments along the horizontal and vertical axis of the camera face to 9 positions on each axis. The source was imaged for 20 min in each position and 214 million total counts were accumulated. The activity distribution of the source, relative to the center pixel, was determined for a 31 x 31 array. The integral uniformity was found to be 2.8%. The RMS error for such a mapping was determined by computer simulation to be 0.46%. The activity distribution was used to correct a high count flood field image for non-uniformities attributable to the Co-57 source. Such a corrected image represents camera plus collimator response to an almost perfectly uniform sheet source
Flood field uniformity testing - effects of crystal hydration
International Nuclear Information System (INIS)
Dimcheva, M.; Sergieva, S.; Doldurova, M.; Jovanovska, A.
2012-01-01
The most basic and sensitive routine quality control (QC) of gamma camera is that of intrinsic flood-field uniformity. The routine QC test must be assessed daily and any nonuniformity must be eliminated before patient testing to eliminate artifacts and false positive or false-negative patient results. The purpose of this study was to compare uniformity analysis results for scintillation crystal hydration with symmetric and asymmetric energy window on the Siemens Symbia T2 SPECTCT camera. Integral and differential uniformity analysis was performed by placing a point source 99m Tc in front of the detector with removed collimator to measure the effect of correction matrix, a count rate and activity volume on intrinsic uniformity. A 15% energy window set symmetrically over the 99m Tc photo peak is equivalent to 140±10% keV or a window spanning 126-154 keV. The results, received from Detector 2 gave the following uniformity parameter values: Both asymmetric energy window images show clearly multiple focal spots due to crystal hydration: discrete hot spots in the asymmetric low window image and discrete cold spots in the asymmetric high window image. The above results are not seen yet on the symmetric window image. We had replaced Detector 2 in order to avoid spots become visible in flood images obtained with the clinical energy window. The uniformity of a gamma camera is maybe the most important parameter that expresses the quality of the camera's performance. Non uniform areas in the field of view can result in misdiagnosed patients and low quality of clinical services. (authors)
Evaluation model development for sprinkler irrigation uniformity ...
African Journals Online (AJOL)
use
Sprinkle and trickle irrigation. The. Blackburn Press, New Jersey, USA. Li JS, Rao MJ (1999). Evaluation method of sprinkler irrigation nonuniformity. Trans. CSAE. 15(4): 78-82. Lin Z, Merkley GP (2011). Relationships between common irrigation application uniformity indicators. Irrig Sci. Online First™, 27 January. 2011.
Evaluation model development for sprinkler irrigation uniformity ...
African Journals Online (AJOL)
A new evaluation method with accompanying software was developed to precisely calculate uniformity from catch-can test data, assuming sprinkler distribution data to be a continuous variable. Two interpolation steps are required to compute unknown water application depths at grid distribution points from radial ...
International Nuclear Information System (INIS)
Mora Ramirez, Erick
2007-01-01
The quality assurance program in a nuclear medicine department aims to minimize errors and artifacts that cover all aspects of clinical practice. The quality control can be seen such as one particular procedure used to meet measurements that can be followed along the time. The intrinsic flood-field uniformity is one of the quality control procedures to evaluate the response of a gamma camera to a spatially uniform flux of an incident gamma radiation over the field of view. The gamma cameras, recording the integral and differential uniformity figures of the intrinsic uniformity during the 2007, were evaluated in order to establish how well the instruments were working. An evaluation of the acquisition protocol which implies the variation of the acquired counts, the energy window width and its placement was performed at the beginning. After that the recorded data were analyzed creating plots which were showing the performance of the systems. Using an energy window placed at 140 keV at 20 %, with matrix size of 512 x 512, acquiring 15 million counts and the source activity close to 700 μC; it was thought that good enough images and uniformities are obtained. Both are within the manufactures requirements; however, increasing the number of acquired counts, images are much better and an improvement in the evaluated parameters can be seen. The performance evaluation of the three gamma cameras was taking into account for approximately 240 days, showing an integral uniformity range of 1.04 - 3.5 % and the range for differential uniformity vary from 0.88 up to 2.7 %. It concludes that the gamma cameras were working quite well, no need to vary the acquisition protocol because it is good enough to perform this test. Also, factors affecting the quality of the images are radioactive waste material not very well shielded and temperature room variations, especially at the beginning of the workday. (author) [es
Chen, Yibin; Chen, Jiaxi; Chen, Xuan; Wang, Min; Wang, Wei
2015-01-01
A new method of uniform sampling is evaluated in this paper. The items and indexes were adopted to evaluate the rationality of the uniform sampling. The evaluation items included convenience of operation, uniformity of sampling site distribution, and accuracy and precision of measured results. The evaluation indexes included operational complexity, occupation rate of sampling site in a row and column, relative accuracy of pill weight, and relative deviation of pill weight. They were obtained from three kinds of drugs with different shape and size by four kinds of sampling methods. Gray correlation analysis was adopted to make the comprehensive evaluation by comparing it with the standard method. The experimental results showed that the convenience of uniform sampling method was 1 (100%), odds ratio of occupation rate in a row and column was infinity, relative accuracy was 99.50-99.89%, reproducibility RSD was 0.45-0.89%, and weighted incidence degree exceeded the standard method. Hence, the uniform sampling method was easy to operate, and the selected samples were distributed uniformly. The experimental results demonstrated that the uniform sampling method has good accuracy and reproducibility, which can be put into use in drugs analysis.
Evaluation of School Uniform Policy in Turkey: A Case Study
Cinoglu, Mustafa
2014-01-01
The purpose of this study is to evaluate the results of current school uniform policies according to views of stakeholders. Descriptive case study method was used for this study to understand the concerns of the stakeholders about school uniforms. Data was collected through interviews with stakeholders and also reviewing the documents in TOKI…
Evaluation of Protocol Uniformity Concerning Laparoscopic Cholecystectomy in The Netherlands
Goossens, Richard H. M.; van Eijk, Daan J.; Lange, Johan F.
2008-01-01
Background Iatrogenic bile duct injury remains a current complication of laparoscopic cholecystectomy. One uniform and standardized protocol, based on the “critical view of safety” concept of Strasberg, should reduce the incidence of this complication. Furthermore, owing to the rapid development of minimally invasive surgery, technicians are becoming more frequently involved. To improve communication between the operating team and technicians, standardized actions should also be defined. The aim of this study was to compare existing protocols for laparoscopic cholecystectomy from various Dutch hospitals. Methods Fifteen Dutch hospitals were contacted for evaluation of their protocols for laparoscopic cholecystectomy. All evaluated protocols were divided into six steps and were compared accordingly. Results In total, 13 hospitals responded—5 academic hospitals, 5 teaching hospitals, 3 community hospitals—of which 10 protocols were usable for comparison. Concerning the trocar positions, only minor differences were found. The concept of “critical view of safety” was represented in just one protocol. Furthermore, the order of clipping and cutting the cystic artery and duct differed. Descriptions of instruments and apparatus were also inconsistent. Conclusions Present protocols differ too much to define a universal procedure among surgeons in The Netherlands. The authors propose one (inter)national standardized protocol, including standardized actions. This uniform standardized protocol has to be officially released and recommended by national scientific associations (e.g., the Dutch Society of Surgery) or international societies (e.g., European Association for Endoscopic Surgery and Society of American Gastrointestinal and Endoscopic Surgeons). The aim is to improve patient safety and professional communication, which are necessary for new developments. PMID:18224485
SU-C-202-07: Protocol and Hardware for Improved Flood Field Calibration of TrueBeam FFF Cine Imaging
Energy Technology Data Exchange (ETDEWEB)
Adamson, J; Faught, A; Yin, F [Duke University Medical Center, Durham, NC (United States)
2016-06-15
Purpose: Flattening filter free photon energies are commonly used for high dose treatments such as SBRT, where localization accuracy is essential. Often, MV cine imaging may be employed to verify correct localization. TrueBeam Electronic Portal Imaging Devices (EPIDs) equipped with the 40×30cm{sup 2} Image Detection Unit (IDU) are prone to image saturation at the image center especially for higher dose rates. While saturation often does not occur for cine imaging during treatment because the beam is attenuated by the patient, the flood field calibration is affected when the standard calibration procedure is followed. Here we describe the hardware and protocol to achieve improved image quality for this model of TrueBeam EPID. Methods: A stainless steel filter of uniform thickness was designed to have sufficient attenuation to avoid panel saturation for both 6XFFF and 10XFFF at the maximum dose rates (1400 MU/min & 2400 MU/min, respectively). The cine imaging flood field calibration was then acquired with the filter in place for the FFF energies under the standard calibration geometry (SDD=150cm). Image quality during MV cine was assessed with & without the modified flood field calibration using a low contrast resolution phantom and an anthropomorphic phantom. Results: When the flood field is acquired using the standard procedure (no filter in place), a pixel gain artifact is clearly present in the image center (r=3cm for 10XFFF at 2400 MU/min) which appears similar to and may be mis-attributed to panel saturation in the subject image. The artifact obscured all low contrast inserts at the image center and was also visible on the anthropomorphic phantom. Using the filter for flood field calibration eliminated the artifact. Conclusion: Use of a modified flood field calibration procedure improves image quality for cine MV imaging with TrueBeams equipped with the 40×30cm{sup 2} IDU.
Evaluation of Uniform Cost Accounting System to Fully Capture Depot Level Repair Costs.
1985-12-01
RD-RI65 522 EVALUATION OF UNIFORM COST ACCOUNTING SYSTEM TO FULLY i/I CAPTURE DEPOT LEVEL REPAIR COSTS (U) NAVAL POSTGRADUATE SCHOOL MONTEREY CA D R...8217.LECTE B ,- THESIS EVALUATION OF UNIFORM COST ACCOUNTING SYSTEM 0TO FULLY CAPTURE DEPOT LEVEL REPAIR COSTS Jby __jDavid Richmond O’Brien lj,,, December...Include Security Classification) EVALUATION OF UNIFORM COST ACCOUNTING SYSTEM TO FULLY CAPTURE DEPOT LEVEL REPAIR COSTS 12 PERSONAL AUTHOR(S) O’Brien- David
Evaluation of protocol uniformity concerning laparoscopic cholecystectomy in The Netherlands
L.S.G.L. Wauben; R.H.M. Goossens (Richard); D.J. van Eijk (Daan); J.F. Lange (Johan)
2008-01-01
textabstractBackground: Iatrogenic bile duct injury remains a current complication of laparoscopic cholecystectomy. One uniform and standardized protocol, based on the "critical view of safety" concept of Strasberg, should reduce the incidence of this complication. Furthermore, owing to the rapid
Alternative methods for evaluation of non-uniformity in nuclear medicine images
International Nuclear Information System (INIS)
Rasaneh, S.; Rajabi, H.; Hajizadeh, E.
2005-01-01
Non-uniformity test is the most essential in daily quality control procedures of nuclear medicine equipment's. However, the calculation of non-uniformity is hindered due to high level of noise in nuclear medicine data. Non-uniformity may be considered as a type of systematic error while noise is certainly a random error. The present methods of uniformity evaluation are not able to distinguish between systematic and random error and therefore produce incorrect results when noise is significant. In the present study, two hypothetical methods have been tested for evaluation of non-uniformity in nuclear medicine images. Materials and Methods: Using the Monte Carlo method, uniform and non-uniform flood images of different matrix sizes and different counts were generated. The uniformity of the images was calculated using the conventional method and proposed methods. The results were compared with the known non-uniformity data of simulated images. Results: It was observed that the value of integral uniformity never went below the recommended values except in small matrix size of high counts (more than 80 millions counts). The differential uniformity was quite insensitive to the degree of non-uniformity in large matrix size. Matrix size of 64*64 was only found to be suitable for the calculation of differential uniformity. It was observed that in uniform images, a small amount of non-uniformity changes the p-value of Kolmogorov-Smirnov test and noise amplitude of fast fourier transformation test significantly while the conventional methods failed to detect the nonuniformity. Conclusion: The conventional methods do not distinguish noise, which is always present in the data and occasional non-uniformity at low count density. In a uniform intact flood image, the difference between maximum and minimum pixel count (the value of integral uniformity) is much more than the recommended values for non-uniformity. After filtration of image, this difference decreases, but remains high
Evaluation of the uniformity of wide circular reference source and application of correction factors
International Nuclear Information System (INIS)
Silva Junior, I.A.; Xavier, M.; Siqueira, P.T.D.; Sordi, G.A.A.; Potiens, M.P.A.
2017-01-01
In this work the uniformity of wide circular reference sources is evaluated. This kind of reference source is still widely used in Brazil. In previous works wide rectangular reference sources were analyzed and it was shown the importance of the application of correction factors in calibration procedures of radiation monitors. Now a transposition of the methods used formerly is performed, evaluating the uniformities of circular reference sources and calculating the associated correction factors. (author)
Uniform System for the Evaluation of Substances (USES), version 4.0
Linders JBHJ; Rikken MGJ; Bakker J; Poel P van der; CSR
2002-01-01
This report describes the fouth version of the Uniform System for the Evaluation of Substances, USES 4.0. USES 4.0 is an integrated risk assessment system for new and existing substances and agricultural and non-agricultural pesticides. The risk assessment system for new and existing substances in
Constantinides, E. D.; Marhefka, R. J.
1994-01-01
A uniform geometrical optics (UGO) and an extended uniform geometrical theory of diffraction (EUTD) are developed for evaluating high frequency electromagnetic (EM) fields within transition regions associated with a two and three dimensional smooth caustic of reflected rays and a composite shadow boundary formed by the caustic termination or the confluence of the caustic with the reflection shadow boundary (RSB). The UGO is a uniform version of the classic geometrical optics (GO). It retains the simple ray optical expressions of classic GO and employs a new set of uniform reflection coefficients. The UGO also includes a uniform version of the complex GO ray field that exists on the dark side of the smooth caustic. The EUTD is an extension of the classic uniform geometrical theory of diffraction (UTD) and accounts for the non-ray optical behavior of the UGO reflected field near caustics by using a two-variable transition function in the expressions for the edge diffraction coefficients. It also uniformly recovers the classic UTD behavior of the edge diffracted field outside the composite shadow boundary transition region. The approach employed for constructing the UGO/EUTD solution is based on a spatial domain physical optics (PO) radiation integral representation for the fields which is then reduced using uniform asymptotic procedures. The UGO/EUTD analysis is also employed to investigate the far-zone RCS problem of plane wave scattering from two and three dimensional polynomial defined surfaces, and uniform reflection, zero-curvature, and edge diffraction coefficients are derived. Numerical results for the scattering and diffraction from cubic and fourth order polynomial strips are also shown and the UGO/EUTD solution is validated by comparison to an independent moment method (MM) solution. The UGO/EUTD solution is also compared with the classic GO/UTD solution. The failure of the classic techniques near caustics and composite shadow boundaries is clearly
International Nuclear Information System (INIS)
MAjor, T.; Polgar, C.; Somogyi, A.; Nemeth, G.
2000-01-01
This study investigated the influence of dwell time optimizations on dose uniformity characterized by dose values in dose points and dose non-uniformity ratio (DNR) and analyzed which implant parameters have influence on the DNR. Double-plane breast implants with catheters arranged in triangular pattern were used for the calculations. At a typical breast implant, dose values in dose reference points inside the target volume and volumes enclosed by given isodose surfaces were calculated and compared for non-optimized and optimized implants. The same 6-cm treatment length was used for the comparisons. Using different optimizations plots of dose non-uniformity ratio as a function of catheter separation, source step size, number of catheters, length of active sections were drawn and the minimum DNR values were determined. Optimization resulted in less variation in dose values over dose points through the whole volume and in the central plane only compared to the non-optimized case. At implant configurations consisting of seven catheters with 15-mm separation, 5-mm source step size and various active lengths adapted according to the type of optimization, the no optimization, geometrical (volume mode) and dose point (on dose points and geometry) optimization resulted in similar treatment volumes, but an increased high dose volume was observed due to the optimization. The dose non-uniformity ratio always had the minimum at average dose over dose normalization points, defined in the midpoints between the catheters through the implant volume. The minimum value of DNR depended on catheter separation, source step size, active length and number of catheters. The optimization had only a small influence on DNR. In addition to the reference points in the central plane only, dose points positioned in the whole implant volume can be used for evaluating the dose uniformity of interstitial implants. The dose optimization increases not only the dose uniformity within the implant but
Uniform System for the Evaluation of Substances (USES), version 4.0
Linders JBHJ; Rikken MGJ; Bakker J; van der Poel P; CSR
2002-01-01
This report describes the fouth version of the Uniform System for the Evaluation of Substances, USES 4.0. USES 4.0 is an integrated risk assessment system for new and existing substances and agricultural and non-agricultural pesticides. The risk assessment system for new and existing substances in USES 4.0 is fully equivalent to EUSES 1.00, the European Union System for the Evaluation of Substances. USES is a decision-support system to be used by central governments, research institutes and t...
Energy Technology Data Exchange (ETDEWEB)
Fu, Lina [Department of Biomedical Engineering, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074 (China); National Engineering Research Center for Nano-Medicine, Huazhong University of Science and Technology, Wuhan 430074 (China); Zhou, Ping [Institute of Organ Transplant of Tongji Hospital, Huazhong University of Science and Technology, Wuhan (China); Zhang, Shengmin [Advanced Biomaterials and Tissue Engineering Center, Huazhong University of Science and Technology, Wuhan (China); Yang, Guang, E-mail: yang_sunny@yahoo.com [Department of Biomedical Engineering, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074 (China); National Engineering Research Center for Nano-Medicine, Huazhong University of Science and Technology, Wuhan 430074 (China)
2013-07-01
Bacterial nanocellulose (BNC) was biosynthesized by Gluconacetobacter xylinus. The surface area, physicochemical structure and morphology of the materials were characterized. Here provides a method for an efficient production of uniform BNC, which is beneficial for the fast characterization and evaluation of BNC. In vitro cytotoxicity of the materials was evaluated by the proliferation, the adhesion, the viability and the morphology of NIH/3T3 cells. Low cytotoxicity of the BNC was observed, and micrographs demonstrate a good proliferation and adhesion of NIH/3T3 cells on BNC. Large area full-thickness skin defects were made on the back of C57BL/6 mice in animal surgery. The wounds were transplanted with BNC films and the results compared to those in a control group. The rehabilitation of the wound surfaces and the pathological sections of mice were investigated and are discussed. Histological examinations demonstrated faster and better healing effect and lower inflammatory response in the BNC group than those in the control group. Preliminary results on wound dressings from BNC show a curative effect promoting the healing of epithelial tissue. BNC is a promising natural polymer with medical applications in wound dressings. - Highlights: • BNC is expected to be a promising material in wound healing and skin transplantation. • We studied surface area, physicochemical structures and morphology of uniform BNC. • Cyto-evaluation results of BNC-based wound dressing show a good biocompatibility. • Large area skin transplantation experiments suggest a good performance of healing.
International Nuclear Information System (INIS)
Fu, Lina; Zhou, Ping; Zhang, Shengmin; Yang, Guang
2013-01-01
Bacterial nanocellulose (BNC) was biosynthesized by Gluconacetobacter xylinus. The surface area, physicochemical structure and morphology of the materials were characterized. Here provides a method for an efficient production of uniform BNC, which is beneficial for the fast characterization and evaluation of BNC. In vitro cytotoxicity of the materials was evaluated by the proliferation, the adhesion, the viability and the morphology of NIH/3T3 cells. Low cytotoxicity of the BNC was observed, and micrographs demonstrate a good proliferation and adhesion of NIH/3T3 cells on BNC. Large area full-thickness skin defects were made on the back of C57BL/6 mice in animal surgery. The wounds were transplanted with BNC films and the results compared to those in a control group. The rehabilitation of the wound surfaces and the pathological sections of mice were investigated and are discussed. Histological examinations demonstrated faster and better healing effect and lower inflammatory response in the BNC group than those in the control group. Preliminary results on wound dressings from BNC show a curative effect promoting the healing of epithelial tissue. BNC is a promising natural polymer with medical applications in wound dressings. - Highlights: • BNC is expected to be a promising material in wound healing and skin transplantation. • We studied surface area, physicochemical structures and morphology of uniform BNC. • Cyto-evaluation results of BNC-based wound dressing show a good biocompatibility. • Large area skin transplantation experiments suggest a good performance of healing
USES 2.0, The Uniform System for the Evaluation of Substances, version 2.0 ; supplement to EUSES
Linders JBHJ; Jager DT; CSR; ECO
1997-01-01
This interim report describes the updated risk assessment system for agricultural and non-agricultural pesticides. It will be integrated with the European Union System for the Evaluation of Substances, EUSES 1.0, into USES 2.0, the second version of the Uniform System for the Evaluation of
Thermal load non-uniformity estimation for superheater tube bundle damage evaluation
Directory of Open Access Journals (Sweden)
Naď Martin
2018-01-01
Full Text Available Industrial boiler damage is a common phenomenon encountered in boiler operation which usually lasts several decades. Since boiler shutdown may be required because of localized failures, it is crucial to predict the most vulnerable parts. If damage occurs, it is necessary to perform root cause analysis and devise corrective measures (repairs, design modifications, etc.. Boiler tube bundles, such as those in superheaters, preheaters and reheaters, are the most exposed and often the most damaged boiler parts. Both short-term and long-term overheating are common causes of tube failures. In these cases, the design temperatures are exceeded, which often results in decrease of remaining creep life. Advanced models for damage evaluation require temperature history, which is available only in rare cases when it has been measured and recorded for the whole service life. However, in most cases it is necessary to estimate the temperature history from available operation history data (inlet and outlet pressures and temperatures etc.. The task may be very challenging because of the combination of complex flow behaviour in the flue gas domain and heat transfer phenomena. This paper focuses on estimating thermal load non-uniformity on superheater tubes via Computational Fluid Dynamics (CFD simulation of flue gas flow including heat transfer within the domain consisting of a furnace and a part of the first stage of the boiler.
EFFICIENCY EVALUATION OF ENTERPRISE INFORMATION SYSTEMS WITH NON-UNIFORM LOAD
Directory of Open Access Journals (Sweden)
I. V. Kalinin
2015-09-01
Full Text Available The paper deals with the problem of characteristics evaluation for enterprise information systems at the design stage. In the design of ERP-systems the most interest characteristic is not the average time, but the probability of timely delivery of different type messages (for example, command, service, multimedia, files, etc. from the sender to the recipient. In addition,the possibility of using the priority information management built on the basis of service disciplines of general form with mixed priorities needs to be considered. An open queuing network with non-uniform data flow is used for solution of this problem. The method for calculation of information systems characteristics is proposed based on the decomposition of the network model. The end results obtained with this approach and by means of priority management are approximate because different classes of message streams at the output and input nodes of the computer system differ from the simple ones. However, result errors of the proposed analytical method are in acceptable limits for engineering calculations as it was shown by simulation in a wide range of parameters corresponding to real systems. Obtained results are usable for optimization problem solution of data transmission networks in modern information systems, involving routing algorithm definition and priorities specification for different classes of messages to provide given delivery time.
A METHOD FOR EVALUATION OF NON-UNIFORM RADIANT-CONVECTIVE LOAD ON HUMAN BODY DURING MENTAL WORK
Directory of Open Access Journals (Sweden)
Lenka Prokšová Zuská
2017-10-01
Full Text Available The objective of this study was to develop a documentation for the amendment of the microclimatic part of the Czech Government Regulation, particularly in a non-uniform radiant-convective load evaluation. Changes in regulation were made based on experimental data obtained on a group of experimental individuals in a climatic chamber. One of the objectives of the climatic chamber experiments was to evaluate whether there was a possibility to use an alternative method, which utilizes a new value – stereotemperature, for the assessment. A group of 24 women was exposed to a non-uniform radiant-convective load in a climatic chamber for 1 hour during their computer work. Measurements were divided according to the globe temperature into 3 stages. The physical parameters of air were continuously measured: the air temperature, globe temperature, air velocity, radiant temperature, relative humidity, stereotemperature and physiological parameters. Thermal sensations of experimental subjects were expressed in the seven-point scale according to EN ISO 7730. The thermal sensation correlated very well with the difference of stereotemperature and the globe temperature. The stereotemperature correlated very well with the radiant temperature. In this work, the composed equations were used to develop the limit values for the thermal stress evaluation in the uniform and non-uniform thermal environment at workplaces. It is possible to determine how the body of an exposed person perceives the non-uniform climatic conditions in the indoor environment, by adding the stereotemperature to government regulations.
Uniform System for the Evaluation of Substances (USES), version 2.0
Linders JBHJ; Jager DT (eds); CSR
1998-01-01
Dit rapport beschrijft de tweede versie van het Uniforme Beoordelingssysteem Stoffen, USES 2.0. Dit bestaat uit een zoveel mogelijk geintegreerd risicobeoordelingssysteem voor nieuwe en bestaande stoffen, landbouwbestrijdingsmiddelen (gewasbeschermingsmiddelen) en
USES 2.0, The Uniform System for the Evaluation of Substances, version 2.0 ; supplement to EUSES
Linders JBHJ; Jager DT (eds.); CSR; ECO
1997-01-01
Dit interimrapport beschrijft het risicobeoordelingssysteem voor landbouw- en niet-landbouwbestrijdingsmiddelen. Het zal worden geintegreerd met het European Union System for the Evaluation of Substances, EUSES 1.0, tot USES 2.0, de tweede versie van het Uniforme Beoordelingssysteem voor
USES 2.0, The Uniform System for the Evaluation of Substances, version 2.0 ; supplement to EUSES
Linders JBHJ; Jager DT (eds.); CSR; ECO
1997-01-01
This interim report describes the updated risk assessment system for agricultural and non-agricultural pesticides. It will be integrated with the European Union System for the Evaluation of Substances, EUSES 1.0, into USES 2.0, the second version of the Uniform System for the Evaluation of Substances. The report is primarily made as preparation to the programming and testing of USES 2.0.
Jager DT; ECO
1995-01-01
UBS, het Uniform Beoordelingssysteem Stoffen (in het engels: USES), is een beslissingsondersteunend gereedschap voor risico-analyse van chemische stoffen. In een eerder rapport is reeds een kader gegeven voor onzekerheidsanalyse van UBS 1.0. In dit rapport worden voorbeeldberekeningen
Design and evaluation of an imaging spectrophotometer incorporating a uniform light source.
Noble, S D; Brown, R B; Crowe, T G
2012-03-01
Accounting for light that is diffusely scattered from a surface is one of the practical challenges in reflectance measurement. Integrating spheres are commonly used for this purpose in point measurements of reflectance and transmittance. This solution is not directly applicable to a spectral imaging application for which diffuse reflectance measurements are desired. In this paper, an imaging spectrophotometer design is presented that employs a uniform light source to provide diffuse illumination. This creates the inverse measurement geometry to the directional illumination/diffuse reflectance mode typically used for point measurements. The final system had a spectral range between 400 and 1000 nm with a 5.2 nm resolution, a field of view of approximately 0.5 m by 0.5 m, and millimeter spatial resolution. Testing results indicate illumination uniformity typically exceeding 95% and reflectance precision better than 1.7%.
Probabilistic uniformities of uniform spaces
Energy Technology Data Exchange (ETDEWEB)
Rodriguez Lopez, J.; Romaguera, S.; Sanchis, M.
2017-07-01
The theory of metric spaces in the fuzzy context has shown to be an interesting area of study not only from a theoretical point of view but also for its applications. Nevertheless, it is usual to consider these spaces as classical topological or uniform spaces and there are not too many results about constructing fuzzy topological structures starting from a fuzzy metric. Maybe, H/{sup o}hle was the first to show how to construct a probabilistic uniformity and a Lowen uniformity from a probabilistic pseudometric /cite{Hohle78,Hohle82a}. His method can be directly translated to the context of fuzzy metrics and allows to characterize the categories of probabilistic uniform spaces or Lowen uniform spaces by means of certain families of fuzzy pseudometrics /cite{RL}. On the other hand, other different fuzzy uniformities can be constructed in a fuzzy metric space: a Hutton $[0,1]$-quasi-uniformity /cite{GGPV06}; a fuzzifiying uniformity /cite{YueShi10}, etc. The paper /cite{GGRLRo} gives a study of several methods of endowing a fuzzy pseudometric space with a probabilistic uniformity and a Hutton $[0,1]$-quasi-uniformity. In 2010, J. Guti/'errez Garc/'{/i}a, S. Romaguera and M. Sanchis /cite{GGRoSanchis10} proved that the category of uniform spaces is isomorphic to a category formed by sets endowed with a fuzzy uniform structure, i. e. a family of fuzzy pseudometrics satisfying certain conditions. We will show here that, by means of this isomorphism, we can obtain several methods to endow a uniform space with a probabilistic uniformity. Furthermore, these constructions allow to obtain a factorization of some functors introduced in /cite{GGRoSanchis10}. (Author)
International Nuclear Information System (INIS)
Reynolds, W.D.; Gillham, R.W.; Cherry, J.A.
1982-01-01
The validity of using a distribution coefficient (Ksub(d)) in the mathematical prediction of strontium and cesium transport through uniform saturated sand was investigated by comparing measured breakthrough curves with curves of simulations using the advection-dispersion and the advection equations. Values for Ksub(d) were determined by batch equilibration tests and, indirectly, by fitting the mathematical model to breakthrough data from column experiments. Although the advection-dispersion equation accurately represented the breakthrough curves for two nonreactive solutes (chloride and tritium), neither it nor the advection equation provided close representations of the strontium and cesium curves. The simulated breakthrough curves for strontium and cesium were nearly symmetrical, whereas the data curves were very asymmetrical, with long tails. Column experiments with different pore-water velocities indicated that the shape of the normalized breakthrough curves was not sensitive to velocity. This suggests that the asymmetry of the measured curves was the result of nonlinear partitioning of the cations between the solid and liquid phases, rather than nonequilibrium effects. The results indicate that the distribution coefficient, when used in advection-dispersion models for prediction of the migration of strontium and cesium in field situations, can result in significant error
International Nuclear Information System (INIS)
Wu, S.C.; Sewell, R.T.
1996-07-01
Conservatism and variability in seismic risk estimates are studied: effects of uniform hazard spectrum (UHS) are examined for deriving probabilistic estimates of risk and in-structure demand levels, as compared to the more-exact use of realistic time history inputs (of given probability) that depend explicitly on magnitude and distance. This approach differs from the conventional in its exhaustive treatment of the ground-motion threat and in its more detailed assessment of component responses to that threat. The approximate UH-ISS (in-structure spectrum) obtained based on UHS appear to be very close to the more-exact results directed computed from scenario earthquakes. This conclusion does not depend on site configurations and structural characteristics. Also, UH-ISS has composite shapes and may not correspond to the characteristics possessed a single earthquake. The shape is largely affected by the structural property in most cases and can be derived approximately from the corresponding UHS. Motions with smooth spectra, however, will not have the same damage potential as those of more realistic motions with jagged spectral shapes. As a result, UHS-based analysis may underestimate the real demands in nonlinear structural analyses
Dumas, J L; Lorchel, F; Perrot, Y; Aletti, P; Noel, A; Wolf, D; Courvoisier, P; Bosset, J F
2007-03-01
The goal of our study was to quantify the limits of the EUD models for use in score functions in inverse planning software, and for clinical application. We focused on oesophagus cancer irradiation. Our evaluation was based on theoretical dose volume histograms (DVH), and we analyzed them using volumetric and linear quadratic EUD models, average and maximum dose concepts, the linear quadratic model and the differential area between each DVH. We evaluated our models using theoretical and more complex DVHs for the above regions of interest. We studied three types of DVH for the target volume: the first followed the ICRU dose homogeneity recommendations; the second was built out of the first requirements and the same average dose was built in for all cases; the third was truncated by a small dose hole. We also built theoretical DVHs for the organs at risk, in order to evaluate the limits of, and the ways to use both EUD(1) and EUD/LQ models, comparing them to the traditional ways of scoring a treatment plan. For each volume of interest we built theoretical treatment plans with differences in the fractionation. We concluded that both volumetric and linear quadratic EUDs should be used. Volumetric EUD(1) takes into account neither hot-cold spot compensation nor the differences in fractionation, but it is more sensitive to the increase of the irradiated volume. With linear quadratic EUD/LQ, a volumetric analysis of fractionation variation effort can be performed.
Zhang, Chunwei; Zhao, Hong; Zhu, Qian; Zhou, Changquan; Qiao, Jiacheng; Zhang, Lu
2018-06-01
Phase-shifting fringe projection profilometry (PSFPP) is a three-dimensional (3D) measurement technique widely adopted in industry measurement. It recovers the 3D profile of measured objects with the aid of the fringe phase. The phase accuracy is among the dominant factors that determine the 3D measurement accuracy. Evaluation of the phase accuracy helps refine adjustable measurement parameters, contributes to evaluating the 3D measurement accuracy, and facilitates improvement of the measurement accuracy. Although PSFPP has been deeply researched, an effective, easy-to-use phase accuracy evaluation method remains to be explored. In this paper, methods based on the uniform-phase coded image (UCI) are presented to accomplish phase accuracy evaluation for PSFPP. These methods work on the principle that the phase value of a UCI can be manually set to be any value, and once the phase value of a UCI pixel is the same as that of a pixel of a corresponding sinusoidal fringe pattern, their phase accuracy values are approximate. The proposed methods provide feasible approaches to evaluating the phase accuracy for PSFPP. Furthermore, they can be used to experimentally research the property of the random and gamma phase errors in PSFPP without the aid of a mathematical model to express random phase error or a large-step phase-shifting algorithm. In this paper, some novel and interesting phenomena are experimentally uncovered with the aid of the proposed methods.
Gunn, Nicholas M; Bachman, Mark; Li, Guann-Pyng; Nelson, Edward L
2010-11-01
The recent identification of rare cell populations within tissues that are associated with specific biological behaviors, for example, progenitor cells, has illuminated a limitation of current technologies to study such adherent cells directly from primary tissues. The micropallet array is a recently developed technology designed to address this limitation by virtue of its capacity to isolate and recover single adherent cells on individual micropallets. The capacity to apply this technology to primary tissues and cells with restricted growth characteristics, particularly adhesion requirements, is critically dependent on the capacity to generate functional extracellular matrix (ECM) coatings. The discontinuous nature of the micropallet array surface provides specific constraints on the processes for generating the desired ECM coatings that are necessary to achieve the full functional capacity of the micropallet array. We have developed strategies, reported herein, to generate functional coatings with various ECM protein components: fibronectin, EHS tumor basement membrane extract, collagen, and laminin-5; confirmed by evaluation for rapid cellular adherence of four dissimilar cell types: fibroblast, breast epithelial, pancreatic epithelial, and myeloma. These findings are important for the dissemination and expanded use of micropallet arrays and similar microtechnologies requiring the integrated use of ECM protein coatings to promote cellular adherence.
Assessment indices for uniform and non-uniform thermal environments
Institute of Scientific and Technical Information of China (English)
2008-01-01
Different assessment indices for thermal environments were compared and selected for proper assessment of indoor thermal environments.30 subjects reported their overall thermal sensation,thermal comfort,and thermal acceptability in uniform and non-uniform conditions.The results show that these three assessment indices provide equivalent evaluations in uniform environments.However,overall thermal sensation differs from the other two indices and cannot be used as a proper index for the evaluation of non-uniform environments.The relationship between the percentage and the mean vote for each index is established.
Energy Technology Data Exchange (ETDEWEB)
Bornatto, P.; Funchal, M.; Bruning, F.; Toledo, H.; Lyra, J.; Fernandes, T.; Toledo, F.; Marciao, C., E-mail: pricila_bornatto@yahoo.com.br [Hospital Erasto Gaertner (LPCC), Curitiba, PR (Brazil). Departamento de Radioterapia
2014-08-15
The purpose of this study is to evaluate the calculation of dose distribution AAA (Varian Medical Systems) for fields with non-uniform fluences considering heterogeneity correction. Five different phantoms were used with different density materials. These phantoms were scanned in the CT BrightSpeed (©GE Healthcare) upon the array of detectors MAPCHECK2 TM (Sun Nuclear Corporation) and irradiated in a linear accelerator 600 CD (Varian Medical Systems) 6MV and rate dose 400MU/min with isocentric setup. The fluences used were exported from IMRT plans, calculated by ECLIPSE™ planning system (Varian Medical Systems), and a 10x10 cm{sup 2} field to assess the heterogeneity correction for uniform fluence. The measured dose distribution was compared to the calculated by Gamma analysis with approval criteria of 3% / 3 mm and 10% threshold. The evaluation was performed using the software SNCPatient (Sun Nuclear Corporation) and considering absolute dose normalized at maximum. The phantoms best performers were those with low density materials, with an average of 99.2% approval. Already phantoms with plates of higher density material presented various fluences below 95% of the points approved. The average value reached 94.3%. It was observed a dependency between fluency and approved percentage points, whereas for the same fluency, 100% of the points have been approved in all phantoms. The approval criteria for IMRT plans recommended in most centers is 3% / 3mm with at least 95% of points approved, it can be concluded that, under these conditions, the IMRT plans with heterogeneity correction can be performed , however the quality control must be careful because the difficulty of the system to accurately predict the dose distribution in certain situations. (author)
Zaid, Abdel Naser; Ghoush, Abeer Abu; Al-Ramahi, Rowa'; Are'r, Mohammed
2012-01-01
The aim of this study was to evaluate whether there exists any discrepancy between the European Pharmacopoeia (Ph. Eur.) and adopted United States Pharmacopeia (USP) tests concerning the weight uniformity measurements of tablet halves after splitting. The USP method does not contain provisions to evaluate split tablets, so here we adopt their whole tablet weight uniformity method. Twenty-nine different commercial scored tablets (local and imported) were divided. The split units were individually weighed and the relative standard deviation (RSD) for each product was calculated and then evaluated according to both the adopted USP and the Ph. Eur. tests of weight uniformity. Twenty out of the 29 products tested failed the USP test, while 14 of them failed the Ph. Eur. test. Nine products passed both the USP and Ph. Eur. tests. Six products passed the Ph. Eur. test but failed the USP test, with all of these products having an RSD greater than 6%. The correlation coefficient between the weight and content of split halves for three randomly selected products-corotenol 100 mg, corotenol 50 mg, and lorazepam 2.5 mg-was found to be 0.986, 0.998, and 0.72, respectively. A clear difference can be seen between outcomes obtained by the two compendial tablet splitting methods with regard to weight uniformity. Results from the USP test showed that tighter measures are needed to pass the test. Our results argue that the Ph. Eur. should revise the existing weight uniformity test on scored tablets to include the RSD parameter in it. The USP should include this adopted test as a specific test for scored tablet halves, not just whole tablets. Manufacturers in some cases will need to improve the quality of the produced scored tablets in order to pass the USP test, especially those with low therapeutic indices. Finally, harmonization between the pharmacopoeias regarding the weight uniformity testing of split tablets is warranted. The aim of this study was to evaluate whether there
Energy Technology Data Exchange (ETDEWEB)
Kurnik, Charles W [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Gowans, Dakers [Left Fork Energy, Harrison, NY (United States); Telarico, Chad [DNV GL, Mahwah, NJ (United States)
2017-11-02
The Commercial and Industrial Lighting Evaluation Protocol (the protocol) describes methods to account for gross energy savings resulting from the programmatic installation of efficient lighting equipment in large populations of commercial, industrial, and other nonresidential facilities. This protocol does not address savings resulting from changes in codes and standards, or from education and training activities. A separate Uniform Methods Project (UMP) protocol, Chapter 3: Commercial and Industrial Lighting Controls Evaluation Protocol, addresses methods for evaluating savings resulting from lighting control measures such as adding time clocks, tuning energy management system commands, and adding occupancy sensors.
BATISTA,Marisa Cristina Aranha; ABREU,Bruno Vinicius de Barros; DUTRA,Richard Pereira; CUNHA,Mayara Soares; AMARAL,Flavia Maria Mendonça do; TORRES,Luce Maria Brandão; RIBEIRO,Maria Nilce de Sousa
2016-01-01
ABSTRACT Geopropolis, a mixture of plant resin, wax, soil and salivary secretion, is produced by the stingless bee Melipona fasciculata. This aim of this study was to investigate the chemical composition and antioxidant activity of geopropolis collected from beehives in two phytogeographical regions, flooded fields and cerrado, in the municipalities of Palmeirândia and Fernando Falcão, Maranhão State, northeastern Brazil. The geopropolis compounds were identified by gas chromatography-mass sp...
Energy Technology Data Exchange (ETDEWEB)
Seoung, Youl Hun [Dept. of of Radiological Science, Cheongju University, Cheongju (Korea, Republic of)
2016-09-15
The purpose of this study was to evaluate the radiolucency for the phantom output to the 3D printing technology. The 3D printing technology was applied for FDM (fused deposition modeling) method and was used the material of ABS (acrylonitrile butadiene styrene) resin. The phantom was designed in cylindrical uniformity. An image uniformity was measured by a cross-sectional images of the 3D printed phantom obtained from the CT equipment. The evaluation of radiolucency was measured exposure dose by the inserted ion-chamber from the 3D printed phantom. As a results, the average of uniformity in the cross-sectional CT image was 2.70 HU and the correlation of radiolucency between PMMA CT phantom and 3D printed ABS phantom is found to have a high correlation to 0.976. In the future, this results will be expected to be used as the basis for the phantom production of the radiation quality control by used 3D printing technology.
International Nuclear Information System (INIS)
Seoung, Youl Hun
2016-01-01
The purpose of this study was to evaluate the radiolucency for the phantom output to the 3D printing technology. The 3D printing technology was applied for FDM (fused deposition modeling) method and was used the material of ABS (acrylonitrile butadiene styrene) resin. The phantom was designed in cylindrical uniformity. An image uniformity was measured by a cross-sectional images of the 3D printed phantom obtained from the CT equipment. The evaluation of radiolucency was measured exposure dose by the inserted ion-chamber from the 3D printed phantom. As a results, the average of uniformity in the cross-sectional CT image was 2.70 HU and the correlation of radiolucency between PMMA CT phantom and 3D printed ABS phantom is found to have a high correlation to 0.976. In the future, this results will be expected to be used as the basis for the phantom production of the radiation quality control by used 3D printing technology
Directory of Open Access Journals (Sweden)
Alfonso Gago-Calderón
2018-04-01
Full Text Available Energy saving in street lighting is garnering more interest and has become a priority in municipal management. Therefore, LED luminaires are gradually becoming prevalent in our cities. Beyond their energy/economic saving potential, quality in public lighting installations concerns aspects such as uniformity and glare which must be maintained if not improved in any installation renewal project using this technology. The high light intensity generated in a discrete point in LED packages and its directional nature result in significant deficiencies in these last two parameters. To soften these effects, translucent covers are being used as one of the most common solutions with the drawback of significant light intensity losses. The objective of this paper is to evaluate the behavior of LED luminaire’s polyamide-based optical covers manufactured with a laser-sintered process. These are designed to improve glare and uniformity output, to minimize light output reductions, and to be industrially manufactured with no increment of cost for their lighting equipment compared to conventional transparent polycarbonate solutions. A laboratory and field lighting test study has been applied to different covers with the same LED lamp and luminaire to compare the performance of three different solutions built with different polymeric materials and with different light transmission surface textures. The photometric results have been observed and discussed to demonstrate the ability to significantly improve the lighting performance of LED luminaires—illuminance and uniformity levels and discomfort and disability glare indexes— using an improved optic cover.
Energy Technology Data Exchange (ETDEWEB)
Kurnik, Charles W [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Dimetrosky, Scott [Apex Analytics, LLC, Boulder, CO (United States); Parkinson, Katie [Apex Analytics, LLC, Boulder, CO (United States); Lieb, Noah [Apex Analytics, LLC, Boulder, CO (United States)
2017-10-19
Given new regulations, increased complexity in the market, and the general shift from CFLs to LEDs, this evaluation protocol was updated in 2017 to shift the focus of the protocols toward LEDs and away from CFLs and to resolve evaluation uncertainties affecting residential lighting incentive programs.
Energy Technology Data Exchange (ETDEWEB)
Nomura, Yasushi; Okuno, Hiroshi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Murazaki, Minoru [Tokyo Nuclear Service Inc., Tokyo (Japan)
2001-11-01
Based on the PWR spent fuel composition data measured at JAERI, two kinds of simplified methods such as ''Equivalent Uniform Burnup'' and ''Equivalent Initial Enrichment'' have been introduced. And relevant evaluation curves have been prepared for criticality safety evaluation of spent fuel storage pool and transport casks, taking burnup of spent fuel into consideration. These simplified methods can be used to obtain an effective neutron multiplication factor for a spent fuel storage/transportation system by using the ORIGEN2.1 burnup code and the KENO-Va criticality code without considering axial burnup profile in spent fuel and other various factors introducing calculated errors. ''Equivalent Uniform Burnup'' is set up for its criticality analysis to be reactivity equivalent with the detailed analysis, in which the experimentally obtained isotopic composition together with a typical axial burnup profile and various factors such as irradiation history are considered on the conservative side. On the other hand, Equivalent Initial Enrichment'' is set up for its criticality analysis to be reactivity equivalent with the detailed analysis such as above when it is used in the so called fresh fuel assumption. (author)
Energy Technology Data Exchange (ETDEWEB)
Kurnik, Charles W. [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Keates, Steven [ADM Associates, Inc., Atlanta, GA (United States)
2017-10-09
This protocol is intended to describe the recommended method when evaluating the whole-building performance of new construction projects in the commercial sector. The protocol focuses on energy conservation measures (ECMs) or packages of measures where evaluators can analyze impacts using building simulation. These ECMs typically require the use of calibrated building simulations under Option D of the International Performance Measurement and Verification Protocol (IPMVP).
Energy Technology Data Exchange (ETDEWEB)
Garrafiel, Fabricio N.; Lykawka, Rochelle; Bacelar, Alexandre; Anes, Mauricio [Hospital de Clinicas de Porto Alegre (HCPA), Porto Alegre, RS (Brazil); Alva-Sanchez, Mirko S.; Pianoschi, Thatiane [Universidade Federal de Ciencias da Saude de Porto Alegre (UFCSPA), Porto Alegre, RS (Brazil)
2016-07-01
The quality control in computed tomography (CT) includes constancy tests concerning CT number measured in a water tank and its response as uniformity, noise and accuracy. Differences to It's performance limits and frequency established by the national legislation and the manufacturers are well known. The objective of this study was to evaluate these tests proceeding the periodicity of national legislation. The tests were conducted over a three equipment of different manufacturers. Each equipment has acquisition parameters and specific phantoms. The equipment presented adequate performance and consistency when compared their results to the limits determined by manufacturers and national legislation. Thus, it is important to evaluate these differences and tailor the testing protocols to meet the established quality requirements. (author)
Energy Technology Data Exchange (ETDEWEB)
Romberger, Jeff [SBW Consulting, Inc., Bellevue, WA (United States)
2017-06-21
An adjustable-speed drive (ASD) includes all devices that vary the speed of a rotating load, including those that vary the motor speed and linkage devices that allow constant motor speed while varying the load speed. The Variable Frequency Drive Evaluation Protocol presented here addresses evaluation issues for variable-frequency drives (VFDs) installed on commercial and industrial motor-driven centrifugal fans and pumps for which torque varies with speed. Constant torque load applications, such as those for positive displacement pumps, are not covered by this protocol.
Uniform peanut performance test 2017
The Uniform Peanut Performance Tests (UPPT) are designed to evaluate the commercial potential of advanced breeding peanut lines not formally released. The tests are performed in ten locations across the peanut production belt. In this study, 2 controls and 14 entries were evaluated at 8 locations....
Directory of Open Access Journals (Sweden)
Coghetto Roland
2016-09-01
Full Text Available In this article, using mostly Pervin [9], Kunzi [6], [8], [7], Williams [11] and Bourbaki [3] works, we formalize in Mizar [2] the notions of quasiuniform space, semi-uniform space and locally uniform space.
Coghetto Roland
2016-01-01
In this article, using mostly Pervin [9], Kunzi [6], [8], [7], Williams [11] and Bourbaki [3] works, we formalize in Mizar [2] the notions of quasiuniform space, semi-uniform space and locally uniform space.
Energy Technology Data Exchange (ETDEWEB)
Kurnik, Charles W. [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Stewart, James [Cadmus, Waltham, MA (United States); Todd, Annika [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
2017-11-01
Residential behavior-based (BB) programs use strategies grounded in the behavioral and social sciences to influence household energy use. These may include providing households with real-time or delayed feedback about their energy use; supplying energy efficiency education and tips; rewarding households for reducing their energy use; comparing households to their peers; and establishing games, tournaments, and competitions. BB programs often target multiple energy end uses and encourage energy savings, demand savings, or both. Savings from BB programs are usually a small percentage of energy use, typically less than 5 percent. Utilities will continue to implement residential BB programs as large-scale, randomized control trials (RCTs); however, some are now experimenting with alternative program designs that are smaller scale; involve new communication channels such as the web, social media, and text messaging; or that employ novel strategies for encouraging behavior change (for example, Facebook competitions). These programs will create new evaluation challenges and may require different evaluation methods than those currently employed to verify any savings they generate. Quasi-experimental methods, however, require stronger assumptions to yield valid savings estimates and may not measure savings with the same degree of validity and accuracy as randomized experiments.
Dowling-Sendor, Benjamin
2002-01-01
Reviews a recent decision in "Littlefield" by the 5th Circuit upholding a school uniform policy. Advises board member who wish to adopt a school uniform policy to solicit input from parents and students, research the experiences of other school districts with uniform policies, and articulate the interests they wish to promote through uniform…
White, Kerry A.
2000-01-01
In 1994, Long Beach (California) Unified School District began requiring uniforms in all elementary and middle schools. Now, half of all urban school systems and many suburban schools have uniform policies. Research on uniforms' effectiveness is mixed. Tightened dress codes may be just as effective and less litigious. (MLH)
Cohn, Carl A.
1996-01-01
Shortly after implementing a mandatory school uniform policy, the Long Beach (California) Public Schools can boast 99% compliance and a substantial reduction in school crime. The uniforms can't be confused with gang colors, save parents money, and help identify outsiders. A sidebar lists ingredients for a mandatory uniform policy. (MLH)
Yu, Xiao-Ying; Barnett, J. Matthew; Amidan, Brett G.; Recknagle, Kurtis P.; Flaherty, Julia E.; Antonio, Ernest J.; Glissmeyer, John A.
2018-03-01
The ANSI/HPS N13.1-2011 standard requires gaseous tracer uniformity testing for sampling associated with stacks used in radioactive air emissions. Sulfur hexafluoride (SF6), a greenhouse gas with a high global warming potential, has long been the gas tracer used in such testing. To reduce the impact of gas tracer tests on the environment, nitrous oxide (N2O) was evaluated as a potential replacement to SF6. The physical evaluation included the development of a test plan to record percent coefficient of variance and the percent maximum deviation between the two gases while considering variables such as fan configuration, injection position, and flow rate. Statistical power was calculated to determine how many sample sets were needed, and computational fluid dynamic modeling was utilized to estimate overall mixing in stacks. Results show there are no significant differences between the behaviors of the two gases, and SF6 modeling corroborated N2O test results. Although, in principle, all tracer gases should behave in an identical manner for measuring mixing within a stack, the series of physical tests guided by statistics was performed to demonstrate the equivalence of N2O testing to SF6 testing in the context of stack qualification tests. The results demonstrate that N2O is a viable choice leading to a four times reduction in global warming impacts for future similar compliance driven testing.
School Uniforms. Research Brief
Walker, Karen
2007-01-01
Does clothing make the person or does the person make the clothing? How does what attire a student wears to school affect their academic achievement? In 1996, President Clinton cited examples of school violence and discipline issues that might have been avoided had the students been wearing uniforms ("School uniforms: Prevention or suppression?").…
Institute of Scientific and Technical Information of China (English)
Linda
2008-01-01
The uniforms for Beijing Olympics’ workers, technical staff and volunteers have been unveiled to mark the 200-day countdown to the Games. The uniforms feature the key element of the clouds of promise and will be in three colors:red for Beijing Olympic Games Committee staff, blue
Xu, Min; Heng, Paul Wan Sia; Liew, Celine Valeria
2015-01-01
To explore the feasibility of coating irregular-shaped drug particles in a modified tangential spray fluidized bed processor (FS processor) and evaluate the coated particles for their coat uniformity and taste-masking efficiency. Paracetamol particles were coated to 20%, w/w weight gain using a taste-masking polymer insoluble in neutral and basic pH but soluble in acidic pH. In-process samples (5, 10 and 15%, w/w coat) and the resultant coated particles (20%, w/w coat) were collected to monitor the changes in their physicochemical attributes. After coating to 20%, w/w coat weight gain, the usable yield was 81% with minimal agglomeration (coat compared with the uncoated particles. A 15%, w/w coat was optimal for inhibiting drug release in salivary pH with subsequent fast dissolution in simulated gastric pH. The FS processor shows promise for direct coating of irregular-shaped drug particles with wide size distribution. The coated particles with 15% coat were sufficiently taste masked and could be useful for further application in orally disintegrating tablet platforms.
Schlippenbach, Trixi von; Oefner, Peter J; Gronwald, Wolfram
2018-03-09
Non-uniform sampling (NUS) allows the accelerated acquisition of multidimensional NMR spectra. The aim of this contribution was the systematic evaluation of the impact of various quantitative NUS parameters on the accuracy and precision of 2D NMR measurements of urinary metabolites. Urine aliquots spiked with varying concentrations (15.6-500.0 µM) of tryptophan, tyrosine, glutamine, glutamic acid, lactic acid, and threonine, which can only be resolved fully by 2D NMR, were used to assess the influence of the sampling scheme, reconstruction algorithm, amount of omitted data points, and seed value on the quantitative performance of NUS in 1 H, 1 H-TOCSY and 1 H, 1 H-COSY45 NMR spectroscopy. Sinusoidal Poisson-gap sampling and a compressed sensing approach employing the iterative re-weighted least squares method for spectral reconstruction allowed a 50% reduction in measurement time while maintaining sufficient quantitative accuracy and precision for both types of homonuclear 2D NMR spectroscopy. Together with other advances in instrument design, such as state-of-the-art cryogenic probes, use of 2D NMR spectroscopy in large biomedical cohort studies seems feasible.
Luttik R; Emans HJB; Poel P van der; Linders JBHJ
1993-01-01
After the presentation of the Evaluation System for Pesticides (ESPE) 1. Agricultural pesticides (Emans et al. 1992) this present report is describing the logical successor ESPE 2: non-agricultural pesticides. Starting with an extensive emission analysis of the different types
Tolerancing a lens for LED uniform illumination
Ryu, Jieun; Sasian, Jose
2017-08-01
A method to evaluate tolerance sensitivities for lenses used to produce uniform illumination is presented. Closed form surfaces are used to define optical surfaces and relative illumination is calculated from light etendue considerations.
Pellicle transmission uniformity requirements
Brown, Thomas L.; Ito, Kunihiro
1998-12-01
Controlling critical dimensions of devices is a constant battle for the photolithography engineer. Current DUV lithographic process exposure latitude is typically 12 to 15% of the total dose. A third of this exposure latitude budget may be used up by a variable related to masking that has not previously received much attention. The emphasis on pellicle transmission has been focused on increasing the average transmission. Much less, attention has been paid to transmission uniformity. This paper explores the total demand on the photospeed latitude budget, the causes of pellicle transmission nonuniformity and examines reasonable expectations for pellicle performance. Modeling is used to examine how the two primary errors in pellicle manufacturing contribute to nonuniformity in transmission. World-class pellicle transmission uniformity standards are discussed and a comparison made between specifications of other components in the photolithographic process. Specifications for other materials or parameters are used as benchmarks to develop a proposed industry standard for pellicle transmission uniformity.
International Nuclear Information System (INIS)
Garcia D, O.C.; Cortes P, A.; Becerril V, A.; Garcia R, J.C.
2002-01-01
A manufacture method of solid phantoms prototype of resin with different radioisotopes is described. The phantom manufactured of molybdenum 99 has an uniformity of 96% determined with a Na(Tl) detector mono channel analyzer with a lead collimator of 1 cm diameter. (Author)
Uniform random number generators
Farr, W. R.
1971-01-01
Methods are presented for the generation of random numbers with uniform and normal distributions. Subprogram listings of Fortran generators for the Univac 1108, SDS 930, and CDC 3200 digital computers are also included. The generators are of the mixed multiplicative type, and the mathematical method employed is that of Marsaglia and Bray.
Restricting uniformly open surjections
Czech Academy of Sciences Publication Activity Database
Kania, Tomasz; Rmoutil, M.
2017-01-01
Roč. 355, č. 9 (2017), s. 925-928 ISSN 1631-073X Institutional support: RVO:67985840 Keywords : Banach space * uniform spaces Subject RIV: BA - General Mathematics OBOR OECD: Pure mathematics Impact factor: 0.396, year: 2016 http://www.sciencedirect.com/science/article/pii/S1631073X17302261?via%3Dihub
Uniformly irradiated polymer film
International Nuclear Information System (INIS)
Fowler, S.L.
1979-01-01
Irradiated film having substantial uniformity in the radiation dosage profile is produced by irradiating the film within a trough having lateral deflection blocks disposed adjacent the film edges for deflecting electrons toward the surface of the trough bottom for further deflecting the electrons toward the film edge
Zhao, Libo; Xia, Yong; Hebibul, Rahman; Wang, Jiuhong; Zhou, Xiangyang; Hu, Yingjie; Li, Zhikang; Luo, Guoxi; Zhao, Yulong; Jiang, Zhuangde
2018-03-01
This paper presents an experimental study using image processing to investigate width and width uniformity of sub-micrometer polyethylene oxide (PEO) lines fabricated by near-filed electrospinning (NFES) technique. An adaptive thresholding method was developed to determine the optimal gray values to accurately extract profiles of printed lines from original optical images. And it was proved with good feasibility. The mechanism of the proposed thresholding method was believed to take advantage of statistic property and get rid of halo induced errors. Triangular method and relative standard deviation (RSD) were introduced to calculate line width and width uniformity, respectively. Based on these image processing methods, the effects of process parameters including substrate speed (v), applied voltage (U), nozzle-to-collector distance (H), and syringe pump flow rate (Q) on width and width uniformity of printed lines were discussed. The research results are helpful to promote the NFES technique for fabricating high resolution micro and sub-micro lines and also helpful to optical image processing at sub-micro level.
Hanna Karaszewska; Maciej Muskała
2012-01-01
The article discusses the problems of women who work in the uniformed services with the particular emphasis on the performing of the occupation of the prison service. It presents the legal issues relating to equal treatment of men and women in the workplace, formal factors influencing their employment, the status of women in prison, and the problems of their conducting in the professional role. The article also presents the results of research conducted in Poland and all over the world, on th...
International Nuclear Information System (INIS)
Hall, D.D.; Mudawar, I.
1997-01-01
A simple methodology for assessing the predictive ability of critical heat flux (CHF) correlations applicable to subcooled flow boiling in a uniformly heated vertical tube is developed. Popular correlations published in handbooks and review articles as well as the most recent correlations are analyzed with the PU-BTPFL CHF database, which contains 29,718 CHF data points. This database is the largest collection of CHF data (vertical upflow of water in a uniformly heated round tube) ever cited in the world literature. The parametric ranges of the CHF database are diameters from 0.3 to 45 mm, length-to-diameter ratios from 2 to 2484, mass velocities from 0.01 x 10 3 to 138 x 10 3 kg/m 2 ·s, pressures from 1 to 223 bars, inlet subcoolings from 0 to 347 C, inlet qualities from -2.63 to 0.00, outlet subcoolings from 0 to 305 C, outlet qualities from -2.13 to 1.00, and CHFs from 0.05 x 10 6 to 276 x 10 6 W/m 2 . The database contains 4,357 data points having a subcooled outlet condition at CHF. A correlation published elsewhere is the most accurate in both low- and high-mass velocity regions, having been developed with a larger database than most correlations. In general, CHF correlations developed from data covering a limited range of flow conditions cannot be extended to other flow conditions without much uncertainty
Directory of Open Access Journals (Sweden)
Hanna Karaszewska
2012-12-01
Full Text Available The article discusses the problems of women who work in the uniformed services with the particular emphasis on the performing of the occupation of the prison service. It presents the legal issues relating to equal treatment of men and women in the workplace, formal factors influencing their employment, the status of women in prison, and the problems of their conducting in the professional role. The article also presents the results of research conducted in Poland and all over the world, on the functioning of women in prison and their relations with officers of the Prison Service, as well as with inmates.
Giovannini, Massimo
2015-01-01
Cosmological singularities are often discussed by means of a gradient expansion that can also describe, during a quasi-de Sitter phase, the progressive suppression of curvature inhomogeneities. While the inflationary event horizon is being formed the two mentioned regimes coexist and a uniform expansion can be conceived and applied to the evolution of spatial gradients across the protoinflationary boundary. It is argued that conventional arguments addressing the preinflationary initial conditions are necessary but generally not sufficient to guarantee a homogeneous onset of the conventional inflationary stage.
Should School Nurses Wear Uniforms?
Journal of School Health, 2001
2001-01-01
This 1958 paper questions whether school nurses should wear uniforms (specifically, white uniforms). It concludes that white uniforms are often associated with the treatment of ill people, and since many people have a fear reaction to them, they are not necessary and are even undesirable. Since school nurses are school staff members, they should…
Skin carcinogenesis following uniform and non-uniform β irradiation
International Nuclear Information System (INIS)
Charles, M.W.; Williams, J.P.; Coggle, J.E.
1989-01-01
Where workers or the general public may be exposed to ionising radiation, the irradiation is rarely uniform. The risk figures and dose limits recommended by the International Commission on Radiological Protection (ICRP) are based largely on clinical and epidemiological studies of reasonably uniform irradiated organs. The paucity of clinical or experimental data for highly non-uniform exposures has prevented the ICRP from providing adequate recommendations. This weakness has led on a number of occasions to the postulate that highly non-uniform exposures of organs could be 100,000 times more carcinogenic than ICRP risk figures would predict. This so-called ''hot-particle hypothesis'' found little support among reputable radiobiologists, but could not be clearly and definitively refuted on the basis of experiment. An experiment, based on skin tumour induction in mouse skin, is described which was developed to test the hypothesis. The skin of 1200 SAS/4 male mice has been exposed to a range of uniform and non-uniform sources of the β emitter 170 Tm (E max ∼ 1 MeV). Non-uniform exposures were produced using arrays of 32 or 8 2-mm diameter sources distributed over the same 8-cm 2 area as a uniform control source. Average skin doses varied from 2-100 Gy. The results for the non-uniform sources show a 30% reduction in tumour incidence by the 32-point array at the lower mean doses compared with the response from uniform sources. The eight-point array showed an order-of-magnitude reduction in tumour incidence compared to uniform irradiation at low doses. These results, in direct contradiction to the ''hot particle hypothesis'', indicate that non-uniform exposures produce significantly fewer tumours than uniform exposures. (author)
Energy Technology Data Exchange (ETDEWEB)
Bouziane, A.
1989-09-01
The integral equation, the finite element and an analytical method are used and compared to compute the state of equilibrium of an oil well. This well is of whatever cross section and is subjected to a uniform pressure and an anisotropic stress field at the infinity. In the first part, the equations of the Mechanics of deformable solids are recalled using dual vectorial spaces theory. These equations are briefly introduced by using a four spaces diagram. In the second part, an analytical method using the complex potentials developed by Muskhelishvili is used to solve the problem. In the third part, three methods of integral equations are developed (direct and indirect). The stress boundary conditions at infinity are taken into account by superimposing a particular solution to the fundamental solution. With such a method, both displacements and stresses are correctly represented as well on the boundary as inside the domain. The finite element method is developed in the fourth part. For complicate shapes of well cross section the used automatic mesh generator does not seem well adapted. In conclusion, the integral equation method gives the results which are in the best agreement with the analytical solutions.
International Nuclear Information System (INIS)
Hall, D.D.; Mudawar, I.
1996-01-01
A simple methodology for assessing the predictive ability of critical heat flux (CHF) correlations applicable to subcooled flow boiling in a uniformly heated vertical tube was developed. Popular correlations published in handbooks and review articles as well as the most recent correlations were analyzed with a database compiled by the authors. The PU-BTPFL CHF Database, which contains 29,718 CHF data points, is the largest collection of CHF data ever cited in the world literature. The parametric ranges of the CHF database are diameters from 0.3 to 45 mm, length-to-diameter ratios from 2 to 2484, mass velocities from 0.01 x 10 3 to 138 x 10 3 kg m -2 s -1 , pressures from 1 to 223 bars, inlet subcoolings from 0 to 347 C, inlet qualities from -2.63 to 0.00, outlet subcoolings from 0 to 305 C, outlet qualities from -2.13 to 1.00, and critical heat fluxes from 0.05 x 10 6 to 276 x 10 6 W m -2 . The database contained 4357 data points having a subcooled outlet condition at CHF. The correlation published in Caira et al. (1993) was the most accurate in both low and high mass velocity regions having been developed with a larger database than most correlations. In general, CHF correlations developed from data covering a limited range of flow conditions can not be extended to other flow conditions without much uncertainty. Subcooled flow boiling has great potential for accommodating the high heat fluxes in such diverse applications as fusion and fission reactors, manufacturing and materials processing, advanced space thermal management systems, accelerator targets, avionic cold plates, X-ray anodes, and high-density multi-chip modules in supercomputers and other modular electronics
Energy Technology Data Exchange (ETDEWEB)
Kurnik, Charles W. [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Simons, George [Itron, Davis, CA (United States); Barsun, Stephan [Itron, Davis, CA (United States)
2017-11-06
The main focus of most evaluations is to determine the energy-savings impacts of the installed measure. This protocol defines a combined heat and power (CHP) measure as a system that sequentially generates both electrical energy and useful thermal energy from one fuel source at a host customer's facility or residence. This protocol is aimed primarily at regulators and administrators of ratepayer-funded CHP programs; however, project developers may find the protocol useful to understand how CHP projects are evaluated.
Energy Technology Data Exchange (ETDEWEB)
Kurnik, Charles W [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Violette, Daniel M. [Navigant, Boulder, CO (United States)
2017-09-01
Addressing other evaluation issues that have been raised in the context of energy efficiency programs, this chapter focuses on methods used to address the persistence of energy savings, which is an important input to the benefit/cost analysis of energy efficiency programs and portfolios. In addition to discussing 'persistence' (which refers to the stream of benefits over time from an energy efficiency measure or program), this chapter provides a summary treatment of these issues -Synergies across programs -Rebound -Dual baselines -Errors in variables (the measurement and/or accuracy of input variables to the evaluation).
Energy Technology Data Exchange (ETDEWEB)
Kurnik, Charles W. [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Romberger, Jeff [SBW Consulting, Inc., Bellevue, WA (United States)
2017-10-09
The HVAC Controls Evaluation Protocol is designed to address evaluation issues for direct digital controls/energy management systems/building automation systems (DDC/EMS/BAS) that are installed to control heating, ventilation, and air-conditioning (HVAC) equipment in commercial and institutional buildings. (This chapter refers to the DDC/EMS/BAS measure as HVAC controls.) This protocol may also be applicable to industrial facilities such as clean rooms and labs, which have either significant HVAC equipment or spaces requiring special environmental conditions.
Quijano, Jessica Kim
2009-07-01
The stability and uniformity of the low-frequency flat fields {L-flat} of the UVIS detector will be assessed by using multiple-pointing observations of the globular clusters 47 Tucanae {NGC104} and Omega Centauri {NGC5139}, thus imaging moderately dense stellar fields. By placing the same star over different portions of the detector and measuring relative changes in its brightness, it will be possible to determine local variations in the response of the UVIS detector. Based on previous experience with STIS and ACS, it is deemed that a total of 9 different pointings will suffice to provide adequate characterization of the flat field stability in any given band. For each filter to be tested, the baseline consists of 9 pointings in a 3X3 box pattern with dither steps of about 25% of the FOV, or 40.5", in either the x or y direction {useful also for CTE measurements, if needed in the future}. During SMOV, the complement of filters to be tested is limited to the following 6 filters: F225W, F275W, F336W, for Omega Cen, and F438W, F606W, and F814W for 47 Tuc. Three long exposures for each target are arranged such that the initial dither position is observed with the appropriate filters for that target within one orbit at a single pointing, so that filter-to-filter differences in the observed star positions can be checked. In addition to the 9 baseline exposures, two sets of short exposures will be taken:a} one short exposure will be taken of OmegaCen with each of the visible filters {F438W, F606W and F814W} in order to check the geometric distortion solution to be obtained with the data from proposal 11444;b} for each target, a single short exposure will be taken with each filter to facilitate the study of the PSF as a function of position on the detector by providing unsaturated images of sparsely-spaced bright stars.This proposal corresponds to Activity Description ID WF39. It should execute only after the following proposal has executed:WF21 - 11434
Ultrasonic transducer design for uniform insonation
International Nuclear Information System (INIS)
Harrison, G.H.; Balcer-Kubiczek, E.K.; McCulloch, D.
1984-01-01
Techniques used in transducer development for acoustical imaging have been evaluated for the purpose of producing broad, uniform ultrasonic fields from planar radiators. Such fields should be useful in hyperthermia, physical therapy, and ultrasonic bioeffects studies. Fourier inversion of the circ function yielded a source velocity distribution proportional to (P/r) exp ((-ik/2Z) (2Z/sup 2/+r/sup 2/)) J/sub 1/(krP/Z), where r is the radial source coordinate, k is the wave number, and P is the desired radius of uniform insonation at a depth Z in water. This source distribution can be truncated without significantly degrading the solution. A simpler solution consists of exponentially shading the edge of an otherwise uniformly excited disk transducer. This approach was successfully approximated experimentally
Energy Technology Data Exchange (ETDEWEB)
Silva Junior, I.A.; Xavier, M.; Siqueira, P.T.D.; Sordi, G.A.A.; Potiens, M.P.A., E-mail: iremarjr@gmail.com [Instituto de Pesquisas Energéticas e Nucleares (IPEN/CNEN-SP), São Paulo, SP (Brazil)
2017-07-01
In this work the uniformity of wide circular reference sources is evaluated. This kind of reference source is still widely used in Brazil. In previous works wide rectangular reference sources were analyzed and it was shown the importance of the application of correction factors in calibration procedures of radiation monitors. Now a transposition of the methods used formerly is performed, evaluating the uniformities of circular reference sources and calculating the associated correction factors. (author)
A scanning point source for quality control of FOV uniformity in GC-PET imaging
International Nuclear Information System (INIS)
Bergmann, H.; Minear, G.; Dobrozemsky, G.; Nowotny, R.; Koenig, B.
2002-01-01
Aim: PET imaging with coincidence cameras (GC-PET) requires additional quality control procedures to check the function of coincidence circuitry and detector zoning. In particular, the uniformity response over the field of view needs special attention since it is known that coincidence counting mode may suffer from non-uniformity effects not present in single photon mode. Materials and methods: An inexpensive linear scanner with a stepper motor and a digital interface to a PC with software allowing versatile scanning modes was developed. The scanner is used with a source holder containing a Sodium-22 point source. While moving the source along the axis of rotation of the GC-PET system, a tomographic acquisition takes place. The scan covers the full axial field of view of the 2-D or 3-D scatter frame. Depending on the acquisition software, point source scanning takes place continuously while only one projection is acquired or is done in step-and-shoot mode with the number of positions equal to the number of gantry steps. Special software was developed to analyse the resulting list mode acquisition files and to produce an image of the recorded coincidence events of each head. Results: Uniformity images of coincidence events were obtained after further correction for systematic sensitivity variations caused by acquisition geometry. The resulting images are analysed visually and by calculating NEMA uniformity indices as for a planar flood field. The method has been applied successfully to two different brands of GC-PET capable gamma cameras. Conclusion: Uniformity of GC-PET can be tested quickly and accurately with a routine QC procedure, using a Sodium-22 scanning point source and an inexpensive mechanical scanning device. The method can be used for both 2-D and 3-D acquisition modes and fills an important gap in the quality control system for GC-PET
Improved Nuclear Medicine Uniformity Assessment with Noise Texture Analysis
Nelson, Jeffrey S.; Christianson, Olav I.; Harkness, Beth A.; Madsen, Mark T.; Mah, Eugene; Thomas, Stephen R.; Zaidi, Habib; Samei, Ehsan
2014-01-01
Because g cameras are generally susceptible to environmental conditions and system vulnerabilities, they require routine evaluation of uniformity performance. The metrics for such evaluations are commonly pixel value-based. Although these metrics are typically successful at identifying regional
School Uniforms: Esprit de Corps.
Ryan, Rosemary P.; Ryan, Thomas E.
1998-01-01
The benefits of school uniforms far outweigh their short-term costs. School uniforms not only keep students safe, but they increase their self-esteem, promote a more positive attitude toward school, lead to improved student behavior, and help blur social-class distinctions. Students are allowed to wear their own political or religious messages,…
Uniform Single Valued Neutrosophic Graphs
Directory of Open Access Journals (Sweden)
S. Broumi
2017-09-01
Full Text Available In this paper, we propose a new concept named the uniform single valued neutrosophic graph. An illustrative example and some properties are examined. Next, we develop an algorithmic approach for computing the complement of the single valued neutrosophic graph. A numerical example is demonstrated for computing the complement of single valued neutrosophic graphs and uniform single valued neutrosophic graph.
Comments on Beckmann's Uniform Reducts
Cook, Stephen
2006-01-01
Arnold Beckmann defined the uniform reduct of a propositional proof system f to be the set of those bounded arithmetical formulas whose propositional translations have polynomial size f-proofs. We prove that the uniform reduct of f + Extended Frege consists of all true bounded arithmetical formulas iff f + Extended Frege simulates every proof system.
Al-Ababneh, Nedal
2014-07-01
We propose an accurate analytical model to calculate the optical crosstalk of a first-order free space optical interconnects system that uses microlenses with circular apertures. The proposed model is derived by evaluating the resulted finite integral in terms of an infinite series of Bessel functions. Compared to the model that uses complex Gaussian functions to expand the aperture function, it is shown that the proposed model is superior in estimating the crosstalk and provides more accurate results. Moreover, it is shown that the proposed model gives results close to that of the numerical model with superior computational efficiency.
Energy Technology Data Exchange (ETDEWEB)
Kurnik, Charles W. [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Carlson, Stephen [DNV GL, Madison, WI (United States)
2017-10-04
This Commercial and Industrial Lighting Controls Evaluation Protocol (the protocol) describes methods to account for energy savings resulting from programmatic installation of lighting control equipment in large populations of commercial, industrial, government, institutional, and other nonresidential facilities. This protocol does not address savings resulting from changes in codes and standards, or from education and training activities. When lighting controls are installed in conjunction with a lighting retrofit project, the lighting control savings must be calculated parametrically with the lighting retrofit project so savings are not double counted.
Energy Technology Data Exchange (ETDEWEB)
Kurnik, Charles W. [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Agnew, Ken [DNV GL, Madison, WI (United States); Goldberg, Mimi [DNV GL, Madison, WI (United States)
2017-11-01
Whole-building retrofits involve the installation of multiple measures. Whole-building retrofit programs take many forms. With a focus on overall building performance, these programs usually begin with an energy audit to identify cost-effective energy efficiency measures for the home. Measures are then installed, either at no cost to the homeowner or partially paid for by rebates and/or financing. The methods described here may also be applied to evaluation of single-measure retrofit programs. Related methods exist for replace-on-failure programs and for new construction, but are not the subject of this chapter.
International Nuclear Information System (INIS)
Jang, S.; Jaszczak, R.J.; Duke Univ. Medical Center, Durham, NC; Gilland, D.R.; Turkington, T.G.; Coleman, R.E.; Tsui, B.M.W.; Metz, C.E.
1998-01-01
The purpose of this work was to evaluate lesion detectability with and without nonuniform attenuation compensation (AC) in myocardial perfusion SPECT imaging in women using an anthropomorphic phantom and receiver operating characteristics (ROC) methodology. Breast attenuation causes artifacts in reconstructed images and may increase the difficulty of diagnosis of myocardial perfusion imaging in women. The null hypothesis tested using the ROC study was that nonuniform AC does not change the lesion detectability in myocardial perfusion SPECT imaging in women. The authors used a filtered backprojection (FBP) reconstruction algorithm and Chang's single iteration method for AC. In conclusion, with the proposed myocardial defect model nuclear medicine physicians demonstrated no significant difference for the detection of the anterior wall defect; however, a greater accuracy for the detection of the inferior wall defect was observed without nonuniform AC than with it. Medical physicists did not demonstrate any statistically significant difference in defect detection accuracy with or without nonuniform AC in the female phantom
Synthetic approaches to uniform polymers.
Ali, Monzur; Brocchini, Steve
2006-12-30
Uniform polymers are characterised by a narrow molecular weight distribution (MWD). Uniformity is also defined by chemical structure in respect of (1) monomer orientation, sequence and stereo-regularity, (2) polymer shape and morphology and (3) chemical functionality. The function of natural polymers such as polypeptides and polynucleotides is related to their conformational structure (e.g. folded tertiary structure). This is only possible because of their high degree of uniformity. While completely uniform synthetic polymers are rare, polymers with broad structure and MWD are widely used in medicine and the biomedical sciences. They are integral components in final dosage forms, drug delivery systems (DDS) and in implantable devices. Increasingly uniform polymers are being used to develop more complex medicines (e.g. delivery of biopharmaceuticals, enhanced formulations or DDS's for existing actives). In addition to the function imparted by any new polymer it will be required to meet stringent specifications in terms of cost containment, scalability, biocompatibility and performance. Synthetic polymers with therapeutic activity are also being developed to exploit their polyvalent properties, which is not possible with low molecular weight molecules. There is need to utilise uniform polymers for applications where the polymer may interact with the systemic circulation, tissues or cellular environment. There are also potential applications (e.g. stimuli responsive coatings) where uniform polymers may be used for their more defined property profile. While it is not yet practical to prepare synthetic polymers to the same high degree of uniformity as proteins, nature also effectively utilises many polymers with lower degrees of uniformity (e.g. polysaccharides, poly(amino acids), polyhydroxyalkanoates). In recent years it has become possible to prepare with practical experimental protocols sufficient quantities of polymers that display many aspects of uniformity. This
Dulin, Charles Dewitt
2016-01-01
The purpose of this research is to evaluate the impact of uniform dress codes on a school's climate for student behavior and learning in four middle schools in North Carolina. The research will compare the perceptions of parents, teachers, and administrators in schools with uniform dress codes against schools without uniform dress codes. This…
Non-uniform temperature gradients and thermal stresses produced ...
Indian Academy of Sciences (India)
thermally-induced stress distributions in a hollow steel sphere heated by a moving uniform ... models to evaluate temperatures according to the frictional heat generation, ... of these thermal effects include thermal stress, strain and deformation.
Activity uniformity of Ir-192 seeds
International Nuclear Information System (INIS)
Ling, C.C.; Gromadzki, Z.C.
1981-01-01
A simple device that uses materials and apparatus commonly available in a radiotherapy department has been designed, fabricated and used in routine quality control relative to the activity uniformity of clinical Ir-192 seeds in ribbons. Detailed evaluation indicated that this system is easy to use and can yield relative activity measurements of individual Ir-192 seeds accurate to within 2%. With this device, activity uniformity of commercial Ir-192 seeds from two manufacturers has been assessed. For the seven shipments of Ir-192 seeds studied, the root mean square variations of individual seed strength from the average of each shipment ranged from 3.4 to 7.1%. Variation in seed activity by more than +- 10% from the average is not uncommon
Uniform excitations in magnetic nanoparticles
DEFF Research Database (Denmark)
Mørup, Steen; Frandsen, Cathrine; Hansen, Mikkel Fougt
2010-01-01
We present a short review of the magnetic excitations in nanoparticles below the superparamagnetic blocking temperature. In this temperature regime, the magnetic dynamics in nanoparticles is dominated by uniform excitations, and this leads to a linear temperature dependence of the magnetization...... and the magnetic hyperfine field, in contrast to the Bloch T3/2 law in bulk materials. The temperature dependence of the average magnetization is conveniently studied by Mössbauer spectroscopy. The energy of the uniform excitations of magnetic nanoparticles can be studied by inelastic neutron scattering....
Uniform excitations in magnetic nanoparticles
Directory of Open Access Journals (Sweden)
Steen Mørup
2010-11-01
Full Text Available We present a short review of the magnetic excitations in nanoparticles below the superparamagnetic blocking temperature. In this temperature regime, the magnetic dynamics in nanoparticles is dominated by uniform excitations, and this leads to a linear temperature dependence of the magnetization and the magnetic hyperfine field, in contrast to the Bloch T3/2 law in bulk materials. The temperature dependence of the average magnetization is conveniently studied by Mössbauer spectroscopy. The energy of the uniform excitations of magnetic nanoparticles can be studied by inelastic neutron scattering.
Uniformity calibration for ICT image
International Nuclear Information System (INIS)
Zeng Gang; Liu Li; Que Jiemin; Zhang Yingping; Yin Yin; Wang Yanfang; Yu Zhongqiang; Yan Yonglian
2004-01-01
The uniformity of ICT image is impaired by beam hardening and the inconsistency of detector units responses. The beam hardening and the nonlinearity of the detector's output have been analyzed. The correction factors are determined experimentally by the detector's responses with different absorption length. The artifacts in the CT image of a symmetrical aluminium cylinder have been eliminated after calibration. (author)
School Uniforms: Guidelines for Principals.
Essex, Nathan L.
2001-01-01
Principals desiring to develop a school-uniform policy should involve parents, teachers, community leaders, and student representatives; beware restrictions on religious and political expression; provide flexibility and assistance for low-income families; implement a pilot program; align the policy with school-safety issues; and consider legal…
Beam uniformity of flat top lasers
Chang, Chao; Cramer, Larry; Danielson, Don; Norby, James
2015-03-01
Many beams that output from standard commercial lasers are multi-mode, with each mode having a different shape and width. They show an overall non-homogeneous energy distribution across the spot size. There may be satellite structures, halos and other deviations from beam uniformity. However, many scientific, industrial and medical applications require flat top spatial energy distribution, high uniformity in the plateau region, and complete absence of hot spots. Reliable standard methods for the evaluation of beam quality are of great importance. Standard methods are required for correct characterization of the laser for its intended application and for tight quality control in laser manufacturing. The International Organization for Standardization (ISO) has published standard procedures and definitions for this purpose. These procedures have not been widely adopted by commercial laser manufacturers. This is due to the fact that they are unreliable because an unrepresentative single-pixel value can seriously distort the result. We hereby propose a metric of beam uniformity, a way of beam profile visualization, procedures to automatically detect hot spots and beam structures, and application examples in our high energy laser production.
46 CFR 310.11 - Cadet uniforms.
2010-10-01
... for State, Territorial or Regional Maritime Academies and Colleges § 310.11 Cadet uniforms. Cadet uniforms shall be supplied at the school in accordance with the uniform regulations of the School. Those... 46 Shipping 8 2010-10-01 2010-10-01 false Cadet uniforms. 310.11 Section 310.11 Shipping MARITIME...
Transversals in 4-uniform hypergraphs
DEFF Research Database (Denmark)
Henning, Michael A; Yeo, Anders
2016-01-01
with maximum degree ∆(H) ≤ 3, then τ (H) ≤ n/4 + m/6, which proves a known conjecture. We show that an easy corollary of our main result is that if H is a 4-uniform hypergraph with n vertices and n edges, then τ (H) ≤3/7 n, which was the main result of the Thomassé-Yeo paper [Combinatorica 27 (2007), 473...
ESPRIT And Uniform Linear Arrays
Roy, R. H.; Goldburg, M.; Ottersten, B. E.; Swindlehurst, A. L.; Viberg, M.; Kailath, T.
1989-11-01
Abstract ¬â€?ESPRIT is a recently developed and patented technique for high-resolution estimation of signal parameters. It exploits an invariance structure designed into the sensor array to achieve a reduction in computational requirements of many orders of magnitude over previous techniques such as MUSIC, Burg's MEM, and Capon's ML, and in addition achieves performance improvement as measured by parameter estimate error variance. It is also manifestly more robust with respect to sensor errors (e.g. gain, phase, and location errors) than other methods as well. Whereas ESPRIT only requires that the sensor array possess a single invariance best visualized by considering two identical but other-wise arbitrary arrays of sensors displaced (but not rotated) with respect to each other, many arrays currently in use in various applications are uniform linear arrays of identical sensor elements. Phased array radars are commonplace in high-resolution direction finding systems, and uniform tapped delay lines (i.e., constant rate A/D converters) are the rule rather than the exception in digital signal processing systems. Such arrays possess many invariances, and are amenable to other types of analysis, which is one of the main reasons such structures are so prevalent. Recent developments in high-resolution algorithms of the signal/noise subspace genre including total least squares (TLS) ESPRIT applied to uniform linear arrays are summarized. ESPRIT is also shown to be a generalization of the root-MUSIC algorithm (applicable only to the case of uniform linear arrays of omni-directional sensors and unimodular cisoids). Comparisons with various estimator bounds, including CramerRao bounds, are presented.
Energy Technology Data Exchange (ETDEWEB)
Blue, C.A.; Sikka, V.K. [Oak Ridge National Lab., TN (United States); Chun, Jung-Hoon [Massachusetts Institute of Technology, Cambridge, MA (United States); Ando, T. [Tufts Univ., Medford, MA (United States)
1997-04-01
The uniform-droplet process is a new method of liquid-metal atomization that results in single droplets that can be used to produce mono-size powders or sprayed-on to substrates to produce near-net shapes with tailored microstructure. The mono-sized powder-production capability of the uniform-droplet process also has the potential of permitting engineered powder blends to produce components of controlled porosity. Metal and alloy powders are commercially produced by at least three different methods: gas atomization, water atomization, and rotating disk. All three methods produce powders of a broad range in size with a very small yield of fine powders with single-sized droplets that can be used to produce mono-size powders or sprayed-on substrates to produce near-net shapes with tailored microstructures. The economical analysis has shown the process to have the potential of reducing capital cost by 50% and operating cost by 37.5% when applied to powder making. For the spray-forming process, a 25% savings is expected in both the capital and operating costs. The project is jointly carried out at Massachusetts Institute of Technology (MIT), Tuffs University, and Oak Ridge National Laboratory (ORNL). Preliminary interactions with both finished parts and powder producers have shown a strong interest in the uniform-droplet process. Systematic studies are being conducted to optimize the process parameters, understand the solidification of droplets and spray deposits, and develop a uniform-droplet-system (UDS) apparatus appropriate for processing engineering alloys.
A quantitative experimental phantom study on MRI image uniformity.
Felemban, Doaa; Verdonschot, Rinus G; Iwamoto, Yuri; Uchiyama, Yuka; Kakimoto, Naoya; Kreiborg, Sven; Murakami, Shumei
2018-05-02
Our goal was to assess MR image uniformity by investigating aspects influencing said uniformity via a method laid out by the National Electrical Manufacturers Association (NEMA). Six metallic materials embedded in a glass phantom were scanned (i.e., Au, Ag, Al, Au-Ag-Pd alloy, Ti and Co-Cr alloy) as well as a reference image. Sequences included Spin Echo (SE) and gradient echo (GRE) scanned in three planes (i.e., Axial, Coronal, and Sagittal). Moreover, three surface coil types (i.e., Head and Neck or HN, Brain, and TMJ coils) and two image correction methods (i.e., Surface Coil Intensity Correction or SCIC, Phased array Uniformity Enhancement or PURE) were employed to evaluate their effectiveness on image uniformity. Image uniformity was assessed using the NEMA peak-deviation non-uniformity method. Results showed that TMJ coils elicited the least uniform image and Brain coils outperformed HN coils when metallic materials were present. Additionally, when metallic materials were present, SE outperformed GRE especially for Co-Cr (particularly in the axial plane). Furthermore, both SCIC and PURE improved image uniformity compared to uncorrected images, and SCIC slightly surpassed PURE when metallic metals were present. Lastly, Co-Cr elicited the least uniform image while other metallic materials generally showed similar patterns (i.e., no significant deviation from images without metallic metals). Overall, a quantitative understanding of the factors influencing MR image uniformity (e.g., coil type, imaging method, metal susceptibility, and post-hoc correction method) is advantageous to optimize image quality, assists clinical interpretation, and may result in improved medical and dental care.
Vote par sondage uniforme incorruptible
Blanchard , Nicolas
2016-01-01
International audience; Introduit en 2012 par David Chaum, le vote par sondage uniforme (random-sample voting) est un protocole de vote basé sur un choix d'une sous-population représentative , permettant de limiter les coûts tout en ayant de nombreux avantages, principalement lorsqu'il est couplé a d'autres techniques comme ThreeBallot. Nous analysons un problème de corruptibilité potentielle où les votants peuvent vendre leur vote au plus offrant et proposons une variation du protocole reméd...
Decidability of uniform recurrence of morphic sequences
Durand , Fabien
2012-01-01
We prove that the uniform recurrence of morphic sequences is decidable. For this we show that the number of derived sequences of uniformly recurrent morphic sequences is bounded. As a corollary we obtain that uniformly recurrent morphic sequences are primitive substitutive sequences.
Uniform Statistical Convergence on Time Scales
Directory of Open Access Journals (Sweden)
Yavuz Altin
2014-01-01
Full Text Available We will introduce the concept of m- and (λ,m-uniform density of a set and m- and (λ,m-uniform statistical convergence on an arbitrary time scale. However, we will define m-uniform Cauchy function on a time scale. Furthermore, some relations about these new notions are also obtained.
Uniform magnetic excitations in nanoparticles
DEFF Research Database (Denmark)
Mørup, Steen; Hansen, Britt Rosendahl
2005-01-01
We have used a spin-wave model to calculate the temperature dependence of the (sublattice) magnetization of magnetic nanoparticles. The uniform precession mode, corresponding to a spin wave with wave vector q=0, is predominant in nanoparticles and gives rise to an approximately linear temperature...... dependence of the (sublattice) magnetization well below the superparamagnetic blocking temperature for both ferro-, ferri-, and antiferromagnetic particles. This is in accordance with the results of a classical model for collective magnetic excitations in nanoparticles. In nanoparticles of antiferromagnetic...... materials, quantum effects give rise to a small deviation from the linear temperature dependence of the (sublattice) magnetization at very low temperatures. The complex nature of the excited precession states of nanoparticles of antiferromagnetic materials, with deviations from antiparallel orientation...
Spacetime transformations from a uniformly accelerated frame
International Nuclear Information System (INIS)
Friedman, Yaakov; Scarr, Tzvi
2013-01-01
We use the generalized Fermi–Walker transport to construct a one-parameter family of inertial frames which are instantaneously comoving to a uniformly accelerated observer. We explain the connection between our approach and that of Mashhoon. We show that our solutions of uniformly accelerated motion have constant acceleration in the comoving frame. Assuming the weak hypothesis of locality, we obtain local spacetime transformations from a uniformly accelerated frame K′ to an inertial frame K. The spacetime transformations between two uniformly accelerated frames with the same acceleration are Lorentz. We compute the metric at an arbitrary point of a uniformly accelerated frame. (paper)
Discovery of Uniformly Expanding Universe
Directory of Open Access Journals (Sweden)
Cahill R. T.
2012-01-01
Full Text Available Saul Perlmutter and the Brian Schmidt – Adam Riess teams reported that their Friedmann-model GR-based analysis of their supernovae magnitude-redshift data re- vealed a new phenomenon of “dark energy” which, it is claimed, forms 73% of the energy / matter density of the present-epoch universe, and which is linked to the further claim of an accelerating expansion of the universe. In 2011 Perlmutter, Schmidt and Riess received the Nobel Prize in Physics “for the discovery of the accelerating ex- pansion of the Universe through observations of distant supernovae”. Here it is shown that (i a generic model-independent analysis of this data reveals a uniformly expanding universe, (ii their analysis actually used Newtonian gravity, and finally (iii the data, as well as the CMB fluctuation data, does not require “dark energy” nor “dark matter”, but instead reveals the phenomenon of a dynamical space, which is absent from the Friedmann model.
School uniforms: tradition, benefit or predicament?
Van Aardt, Annette Marie; Wilken, Ilani
2012-01-01
This article focuses on the controversies surrounding school uniforms. Roleplayers in this debate in South Africa are parents, learners and educators, and arguments centre on aspects such as identity, economy and the equalising effect of school uniforms, which are considered in the literature to be benefits. Opposing viewpoints highlight the fact that compulsory uniforms infringe on learners’ constitutional rights to self-expression. The aim of this research was to determine the perspectives ...
Moes, Johannes J; Ruijken, Marco M; Gout, Erik; Frijlink, Henderik W; Ugwoke, Michael I
2008-01-01
Near-infrared (NIR)spectroscopy was employed as a process analytical technique in three steps of tabletting process: to monitor the blend homogeneity, evaluate the content uniformity of tablets and determine the tablets coating thickness. A diode-array spectrometer mounted on a lab blender (SP15 NIR
School Uniform Policies in Public Schools
Brunsma, David L.
2006-01-01
The movement for school uniforms in public schools continues to grow despite the author's research indicating little if any impact on student behavior, achievement, and self-esteem. The author examines the distribution of uniform policies by region and demographics, the impact of these policies on perceptions of school climate and safety, and…
School Uniform Policies: Students' Views of Effectiveness.
McCarthy, Teresa M.; Moreno, Josephine
2001-01-01
Focus-group interviews of New York City middle-school students about their perceptions of the effectiveness of the school-uniform policy. Finds that students' perceptions of the effects of school-uniform policy on school culture varied considerably with those intended by the principal. (Contains 40 references.) (PKP)
School Uniforms and Discourses on Childhood.
Bodine, Ann
2003-01-01
This ethnographic study examined the introduction of school uniforms in the public schools of one California city. Findings indicated that the uniform issue intersected with issues such as student safety and violence, family stress, egalitarianism, competitive dressing, and a power struggle over shaping the childhood environment. It was concluded…
Student Dress Codes and Uniforms. Research Brief
Johnston, Howard
2009-01-01
According to an Education Commission of the States "Policy Report", research on the effects of dress code and school uniform policies is inconclusive and mixed. Some researchers find positive effects; others claim no effects or only perceived effects. While no state has legislatively mandated the wearing of school uniforms, 28 states and…
School Dress Codes and Uniform Policies.
Anderson, Wendell
2002-01-01
Opinions abound on what students should wear to class. Some see student dress as a safety issue; others see it as a student-rights issue. The issue of dress codes and uniform policies has been tackled in the classroom, the boardroom, and the courtroom. This Policy Report examines the whole fabric of the debate on dress codes and uniform policies…
A School Uniform Program That Works.
Loesch, Paul C.
1995-01-01
According to advocates, school uniforms reduce gang influence, decrease families' clothing expenditures, and help mitigate potentially divisive cultural and economic differences. Aiming to improve school climate, a California elementary school adopted uniforms as a source of pride and affiliation. This article describes the development of the…
Devaney's chaos on uniform limit maps
International Nuclear Information System (INIS)
Yan Kesong; Zeng Fanping; Zhang Gengrong
2011-01-01
Highlights: → The transitivity may not been inherited even if the sequence functions mixing. → The sensitivity may not been inherited even if the iterates of sequence have some uniform convergence. → Some equivalence conditions for the transitivity and sensitivity for uniform limit function are given. → A non-transitive sequence may converge uniformly to a transitive map. - Abstract: Let (X, d) be a compact metric space and f n : X → X a sequence of continuous maps such that (f n ) converges uniformly to a map f. The purpose of this paper is to study the Devaney's chaos on the uniform limit f. On the one hand, we show that f is not necessarily transitive even if all f n mixing, and the sensitive dependence on initial conditions may not been inherited to f even if the iterates of the sequence have some uniform convergence, which correct two wrong claims in . On the other hand, we give some equivalence conditions for the uniform limit f to be transitive and to have sensitive dependence on initial conditions. Moreover, we present an example to show that a non-transitive sequence may converge uniformly to a transitive map.
Growth functions for some uniformly amenable groups
Directory of Open Access Journals (Sweden)
Dronka Janusz
2017-04-01
Full Text Available We present a simple constructive proof of the fact that every abelian discrete group is uniformly amenable. We improve the growth function obtained earlier and find the optimal growth function in a particular case. We also compute a growth function for some non-abelian uniformly amenable group.
On Uniform Exponential Trichotomy in Banach Spaces
Directory of Open Access Journals (Sweden)
Kovacs Monteola Ilona
2014-06-01
Full Text Available In this paper we consider three concepts of uniform exponential trichotomy on the half-line in the general framework of evolution operators in Banach spaces. We obtain a systematic classification of uniform exponential trichotomy concepts and the connections between them.
Controlling of density uniformity of polyacrylate foams
International Nuclear Information System (INIS)
Shan Wenwen; Yuan Baohe; Wang Yanhong; Xu Jiayun; Zhang Lin
2010-01-01
The density non-uniformity existing in most low-density foams will affect performance of the foams. The trimethylolpropane trimethacrylate (TMPTA) foam targets were prepared and controlling methods of the foams, density uniformity were explored together with its forming mechanism. It has been found that the UV-light with high intensity can improve the distribution uniformity of the free radicals induced by UV photons in the solvents, thus improve the density uniformity of the foams. In addition, container wall would influence the concentration distribution of the solution, which affects the density uniformity of the foams. Thus, the UV-light with high intensity was chosen together with polytetrafluoroethylene molds instead of glass molds to prepare the foams with the density non-uniformity less than 10%. β-ray detection technology was used to measure the density uniformity of the TMPTA foams with the density in the range of 10 to 100 mg · cm -3 , and the results show that the lower the foam density is, the worse the density uniformity is. (authors)
A Uniform Syntax and Discourse Structure
DEFF Research Database (Denmark)
Hardt, Daniel
2013-01-01
I present arguments in favor of the Uniformity Hypothesis: the hypothesis that discourse can extend syntax dependencies without conflicting with them. I consider arguments that Uniformity is violated in certain cases involving quotation, and I argue that the cases presented in the literature...
Directory of Open Access Journals (Sweden)
Marcus V. A. M. de Oliveira
2008-03-01
Full Text Available O uso da fertirrigação possibilita a obtenção de bons resultados, todavia é notada a necessidade de trabalhos que venham possibilitar a adoção correta da técnica. Dessa forma ,o presente trabalho buscou comparar a uniformidade de distribuição do potássio e do nitrogênio em sistema de irrigação por gotejamento. A solução de fertilizantes foi injetada durante 25 minutos, sendo recolhidas amostras de solução em diferentes momentos, durante e após ter sido finalizada a operação de injeção, tendo sido especificado o tempo de 35 minutos após o início da operação de injeção da solução de fertilizantes, como tempo-limite para a coleta da última amostra. As amostras coletadas tiveram os teores de potássio (K+ e nitrogênio (NO3- + NH4+ determinados. Com os resultados obtidos, concluiu-se que não houve variação significativa da uniformidade de distribuição de nitrogênio e de potássio no sistema de irrigação por gotejamento; maiores tempos de funcionamento de sistemas de irrigação, quando em operação de fertirrigação, possibilitam melhores uniformidades de distribuição do fertilizante, e deve-se calcular o tempo de lavagem do sistema de irrigação, pois é uma forma de melhorar a uniformidade de distribuição do fertilizante no campo.The use of the fertigation makes possible obtaining good results; however it was noticed the necessity of studies that make possible the correct adoption of this technique. Thus the present study aimed to compare the distribution uniformity of potassium and nitrogen when applied through a trickle irrigation system. The fertilizers solution was applied during 25 minutes; samples of solution were collected at different moments during and after the product injection through irrigation water, and the time limit to collect the last sample was specified as 35 minutes after injection operations begun. In the collected samples were determined the contents of potassium (K+ and
DEFF Research Database (Denmark)
Kohlenbach, Ulrich
2002-01-01
The so-called weak Konig's lemma WKL asserts the existence of an infinite path b in any infinite binary tree (given by a representing function f). Based on this principle one can formulate subsystems of higher-order arithmetic which allow to carry out very substantial parts of classical mathematics...... which-relative to PRA -implies the schema of 10-induction). In this setting one can consider also a uniform version UWKL of WKL which asserts the existence of a functional which selects uniformly in a given infinite binary tree f an infinite path f of that tree. This uniform version of WKL...
X-ray radiographic technique for measuring density uniformity of silica aerogel
International Nuclear Information System (INIS)
Tabata, Makoto; Hatakeyama, Yoshikiyo; Adachi, Ichiro; Morita, Takeshi; Nishikawa, Keiko
2013-01-01
This paper proposes a new X-ray radiographic technique for measuring density uniformity of silica aerogels used as radiator in proximity-focusing ring-imaging Cherenkov detectors. To obtain high performance in a large-area detector, a key characteristic of radiator is the density (i.e. refractive index) uniformity of an individual aerogel monolith. At a refractive index of n=1.05, our requirement for the refractive index uniformity in the transverse plane direction of an aerogel tile is |δ(n−1)/(n−1)|<4% in a focusing dual layer radiator (with different refractive indices) scheme. We applied the radiographic technique to evaluate the density uniformity of our original aerogels from a trial production and that of Panasonic products (SP-50) as a reference, and to confirm they have sufficient density uniformity within ±1% along the transverse plane direction. The measurement results show that the proposed technique can quantitatively estimate the density uniformity of aerogels.
Uniform Facility Data Set US (UFDS-1997)
U.S. Department of Health & Human Services — The Uniform Facility Data Set (UFDS), formerly the National Drug and Alcohol Treatment Unit Survey or NDATUS, was designed to measure the scope and use of drug abuse...
Uniform Facility Data Set US (UFDS-1998)
U.S. Department of Health & Human Services — The Uniform Facility Data Set (UFDS) was designed to measure the scope and use of drug abuse treatment services in the United States. The survey collects information...
Nonimaging solar concentrator with uniform irradiance
Winston, Roland; O'Gallagher, Joseph J.; Gee, Randy C.
2004-09-01
We report results of a study our group has undertaken under NREL/DOE auspices to design a solar concentrator with uniform irradiance on a planar target. This attribute is especially important for photovoltaic concentrators.
Uniforms, status and professional boundaries in hospital.
Timmons, Stephen; East, Linda
2011-11-01
Despite their comparative neglect analytically, uniforms play a key role in the delineation of occupational boundaries and the formation of professional identity in healthcare. This paper analyses a change to the system of uniforms in one UK hospital, where management have required all professions (with the exception of doctors) to wear the same 'corporate' uniform. Focus groups were conducted with the professionals and patients. We analyse this initiative as a kind of McDonaldisation, seeking to create a new 'corporate' worker whose allegiance is principally to the organisation, rather than a profession. Our findings show how important uniforms are to their wearers, both in terms of the defence of professional boundaries and status, as well as the construction of professional identity. © 2011 The Authors. Sociology of Health & Illness © 2011 Foundation for the Sociology of Health & Illness/Blackwell Publishing Ltd.
Uniform Reserve Training and Retirement Category Administration
National Research Council Canada - National Science Library
Kohner, D
1997-01-01
This Instruction implement policy as provided in DoD Directive 1215.6, assigns responsibilities and prescribes procedures that pertain to the designation and use of uniform Reserve component (RC) categories (RCCs...
Uniform emergency codes: will they improve safety?
2005-01-01
There are pros and cons to uniform code systems, according to emergency medicine experts. Uniformity can be a benefit when ED nurses and other staff work at several facilities. It's critical that your staff understand not only what the codes stand for, but what they must do when codes are called. If your state institutes a new system, be sure to hold regular drills to familiarize your ED staff.
Quasiparticles in non-uniformly magnetized plasma
International Nuclear Information System (INIS)
Sosenko, P.P.
1994-01-01
A quasiparticle concept is generalized for the case of non-uniformly magnetized plasma. Exact and reduced continuity equations for the microscopic density in the quasiparticle phase space are derived, and the nature of quasiparticles is analyzed. The theory is developed for the general case of relativistic particles in electromagnetic fields, besides non-uniform but stationary magnetic fields. Effects of non-stationary magnetic fields are briefly investigated also. 26 refs
The mathematical description of uniformity and related theorems
International Nuclear Information System (INIS)
Luo Chuanwen; Yi Chundi; Wang Gang; Li Longsuo; Wang Chuncheng
2009-01-01
Uniform index is a conception that can describe the uniformity of a finite point set in a polyhedron, and is closely related to chaos. In order to study uniform index, the concept of contained uniform index is defined, which is similar to uniform index and has good mathematical properties. In this paper, we prove the convergence of the contained uniform index, and develop the base of proving the convergence of uniform index.
Environmental radionuclide concentrations: statistical model to determine uniformity of distribution
International Nuclear Information System (INIS)
Cawley, C.N.; Fenyves, E.J.; Spitzberg, D.B.; Wiorkowski, J.; Chehroudi, M.T.
1980-01-01
In the evaluation of data from environmental sampling and measurement, a basic question is whether the radionuclide (or pollutant) is distributed uniformly. Since physical measurements have associated errors, it is inappropriate to consider the measurements alone in this determination. Hence, a statistical model has been developed. It consists of a weighted analysis of variance with subsequent t-tests between weighted and independent means. A computer program to perform the calculations is included
Bachegowda, Lohith S; Cheng, Yan H; Long, Thomas; Shaz, Beth H
2017-01-01
-Substantial variability between different antibody titration methods prompted development and introduction of uniform methods in 2008. -To determine whether uniform methods consistently decrease interlaboratory variation in proficiency testing. -Proficiency testing data for antibody titration between 2009 and 2013 were obtained from the College of American Pathologists. Each laboratory was supplied plasma and red cells to determine anti-A and anti-D antibody titers by their standard method: gel or tube by uniform or other methods at different testing phases (immediate spin and/or room temperature [anti-A], and/or anti-human globulin [AHG: anti-A and anti-D]) with different additives. Interlaboratory variations were compared by analyzing the distribution of titer results by method and phase. -A median of 574 and 1100 responses were reported for anti-A and anti-D antibody titers, respectively, during a 5-year period. The 3 most frequent (median) methods performed for anti-A antibody were uniform tube room temperature (147.5; range, 119-159), uniform tube AHG (143.5; range, 134-150), and other tube AHG (97; range, 82-116); for anti-D antibody, the methods were other tube (451; range, 431-465), uniform tube (404; range, 382-462), and uniform gel (137; range, 121-153). Of the larger reported methods, uniform gel AHG phase for anti-A and anti-D antibodies had the most participants with the same result (mode). For anti-A antibody, 0 of 8 (uniform versus other tube room temperature) and 1 of 8 (uniform versus other tube AHG), and for anti-D antibody, 0 of 8 (uniform versus other tube) and 0 of 8 (uniform versus other gel) proficiency tests showed significant titer variability reduction. -Uniform methods harmonize laboratory techniques but rarely reduce interlaboratory titer variance in comparison with other methods.
Identifying uniformly mutated segments within repeats.
Sahinalp, S Cenk; Eichler, Evan; Goldberg, Paul; Berenbrink, Petra; Friedetzky, Tom; Ergun, Funda
2004-12-01
Given a long string of characters from a constant size alphabet we present an algorithm to determine whether its characters have been generated by a single i.i.d. random source. More specifically, consider all possible n-coin models for generating a binary string S, where each bit of S is generated via an independent toss of one of the n coins in the model. The choice of which coin to toss is decided by a random walk on the set of coins where the probability of a coin change is much lower than the probability of using the same coin repeatedly. We present a procedure to evaluate the likelihood of a n-coin model for given S, subject a uniform prior distribution over the parameters of the model (that represent mutation rates and probabilities of copying events). In the absence of detailed prior knowledge of these parameters, the algorithm can be used to determine whether the a posteriori probability for n=1 is higher than for any other n>1. Our algorithm runs in time O(l4logl), where l is the length of S, through a dynamic programming approach which exploits the assumed convexity of the a posteriori probability for n. Our test can be used in the analysis of long alignments between pairs of genomic sequences in a number of ways. For example, functional regions in genome sequences exhibit much lower mutation rates than non-functional regions. Because our test provides means for determining variations in the mutation rate, it may be used to distinguish functional regions from non-functional ones. Another application is in determining whether two highly similar, thus evolutionarily related, genome segments are the result of a single copy event or of a complex series of copy events. This is particularly an issue in evolutionary studies of genome regions rich with repeat segments (especially tandemly repeated segments).
7 CFR 1005.61 - Computation of uniform prices.
2010-01-01
... month, the market administrator shall compute a uniform butterfat price, a uniform skim milk price, and...) and (a)(2) of this section. (b) Uniform skim milk price. The uniform skim milk price per hundredweight... paragraph (a) of this section times 3.5 pounds of butterfat; and (2) Multiply the uniform skim milk price...
7 CFR 1006.61 - Computation of uniform prices.
2010-01-01
..., the market administrator shall compute a uniform butterfat price, a uniform skim milk price, and a... section. (b) Uniform skim milk price. The uniform skim milk price per hundredweight, rounded to the... paragraph (a) of this section times 3.5 pounds of butterfat; and (2) Multiply the uniform skim milk price...
7 CFR 1131.61 - Computation of uniform prices.
2010-01-01
..., the market administrator shall compute a uniform butterfat price, a uniform skim milk price, and a... section. (b) Uniform skim milk price. The uniform skim milk price per hundredweight, rounded to the... paragraph (a) of this section times 3.5 pounds of butterfat; and (2) Multiply the uniform skim milk price...
7 CFR 1007.61 - Computation of uniform prices.
2010-01-01
..., the market administrator shall compute a uniform butterfat price, a uniform skim milk price, and a... section. (b) Uniform skim milk price. The uniform skim milk price per hundredweight, rounded to the... paragraph (a) of this section times 3.5 pounds of butterfat; and (2) Multiply the uniform skim milk price...
Uniform color space is not homogeneous
Kuehni, Rolf G.
2002-06-01
Historical data of chroma scaling and hue scaling are compared and evidence is shown that we do not have a reliable basis in either case. Several data sets indicate explicitly or implicitly that the number of constant sized hue differences between unique hues as well as in the quadrants of the a*, b* diagram differs making what is commonly regarded as uniform color space inhomogeneous. This problem is also shown to affect the OSA-UCS space. A Euclidean uniform psychological or psychophysical color space appears to be impossible.
On Uniformly finitely extensible Banach spaces
Castillo, Jesús M. F.; Ferenczi, Valentin; Moreno, Yolanda
2013-01-01
We continue the study of Uniformly Finitely Extensible Banach spaces (in short, UFO) initiated in Moreno-Plichko, \\emph{On automorphic Banach spaces}, Israel J. Math. 169 (2009) 29--45 and Castillo-Plichko, \\emph{Banach spaces in various positions.} J. Funct. Anal. 259 (2010) 2098-2138. We show that they have the Uniform Approximation Property of Pe\\l czy\\'nski and Rosenthal and are compactly extensible. We will also consider their connection with the automorphic space problem of Lindenstraus...
Uniform topology on EQ-algebras
Directory of Open Access Journals (Sweden)
Yang Jiang
2017-04-01
Full Text Available In this paper, we use filters of an EQ-algebra E to induce a uniform structure (E, , and then the part induce a uniform topology in E. We prove that the pair (E, is a topological EQ-algebra, and some properties of (E, are investigated. In particular, we show that (E, is a first-countable, zero-dimensional, disconnected and completely regular space. Finally, by using convergence of nets, the convergence of topological EQ-algebras is obtained.
Uniformity factor of temperature difference in heat exchanger networks
International Nuclear Information System (INIS)
Chen, Shang; Cui, Guo-min
2016-01-01
Highlights: • A uniformity factor of temperature (UFTD) is proposed to heat exchanger network (HEN). • A novel stage-wise superstructure with inner utilities is presented based on UFTD. • New model and DE method is combined as an optimization method. • Optimal HEN structures with inner utilities can be obtained with new method. - Abstract: A uniformity factor of temperature difference (UFTD) is proposed and set up to guide the optimization of Heat exchanger network (HEN). At first, the factor is presented to evaluate the whole enhancement of HEN by handling the logical mean temperature difference as two-dimensional discrete temperature field in system. Then, the factor is applied to different HENs, of which the comparison indicates that a more uniform discrete temperature field leads to a lower UFTD which correlated with a better whole enhancement to improve the optimization level of HEN. A novel stage-wise superstructure model where inner utility can be generated is presented for further analysis of correlation between UFTD and the efficiency of HEN, and more optimal HEN structures can be obtained as inner utility added. Inner utility appears to violate the thermodynamic law, but it makes the discrete temperature field more uniform and improves the heat transfer efficiency of the whole HEN, which brings much more profit than the side effect of inner utility. In sum, the UFTD can not only evaluate the optimization level of the HEN, but also be an optimization object to design new HEN with higher efficiency of energy utilization and lower total annual cost.
MODERATOR ELEMENTS FOR UNIFORM POWER NUCLEAR REACTOR
Balent, R.
1963-03-12
This patent describes a method of obtaining a flatter flux and more uniform power generation across the core of a nuclear reactor. The method comprises using moderator elements having differing moderating strength. The elements have an increasing amount of the better moderating material as a function of radial and/or axial distance from the reactor core center. (AEC)
Coded aperture imaging with uniformly redundant arrays
International Nuclear Information System (INIS)
Fenimore, E.E.; Cannon, T.M.
1980-01-01
A system is described which uses uniformly redundant arrays to image non-focusable radiation. The array is used in conjunction with a balanced correlation technique to provide a system with no artifacts so that virtually limitless signal-to-noise ratio is obtained with high transmission characteristics. The array is mosaicked to reduce required detector size over conventional array detectors. 15 claims
School Uniform Revisited: Procedure, Pressure and Equality
Carney, Damian; Sinclair, Adele
2006-01-01
The House of Lords' decision in "R. (on the application of Begum) v. The Headteacher and Governors of Denbigh High School" considered whether a particular school uniform policy infringed a student's right to manifest her religion under Article 9. This paper analyses the content of this decision, and explores how schools should approach…
School Uniforms in Urban Public High Schools
Draa, Virginia Ann Bendel
2005-01-01
The purpose of this study was to determine whether or not the implementation of a mandatory uniform policy in urban public high schools improved school performance measures at the building level for rates of attendance, graduation, academic proficiency, and student conduct as measured by rates of suspensions and expulsions. Sixty-four secondary…
Mandatory School Uniforms and Freedom of Expression
Vopat, Mark C.
2010-01-01
On 10 December 2007 the Akron City School Board--following the precedent set by many school systems across the United States and the world--instituted a policy of mandatory school uniforms for all students in grades K-8. The measure was met with mixed reviews. While many parents supported the measure, a small group of parents from a selective,…
Dynamic Uniform Scaling for Multiobjective Genetic Algorithms
DEFF Research Database (Denmark)
Pedersen, Gerulf; Goldberg, David E.
2004-01-01
Before Multiobjective Evolutionary Algorithms (MOEAs) can be used as a widespread tool for solving arbitrary real world problems there are some salient issues which require further investigation. One of these issues is how a uniform distribution of solutions along the Pareto non-dominated front c...
UMAPRM: Uniformly sampling the medial axis
Yeh, Hsin-Yi Cindy
2014-05-01
© 2014 IEEE. Maintaining clearance, or distance from obstacles, is a vital component of successful motion planning algorithms. Maintaining high clearance often creates safer paths for robots. Contemporary sampling-based planning algorithms That utilize The medial axis, or The set of all points equidistant To Two or more obstacles, produce higher clearance paths. However, They are biased heavily Toward certain portions of The medial axis, sometimes ignoring parts critical To planning, e.g., specific Types of narrow passages. We introduce Uniform Medial Axis Probabilistic RoadMap (UMAPRM), a novel planning variant That generates samples uniformly on The medial axis of The free portion of Cspace. We Theoretically analyze The distribution generated by UMAPRM and show its uniformity. Our results show That UMAPRM\\'s distribution of samples along The medial axis is not only uniform but also preferable To other medial axis samplers in certain planning problems. We demonstrate That UMAPRM has negligible computational overhead over other sampling Techniques and can solve problems The others could not, e.g., a bug Trap. Finally, we demonstrate UMAPRM successfully generates higher clearance paths in The examples.
An analysis of the uniform core experiment
Energy Technology Data Exchange (ETDEWEB)
Waterson, R H
1973-10-15
This report describes an analysis of the Uniform Core of HITREX using the WIMS E codes, and presents the results of theory/experiment comparisons. The overall picture is one of good agreement for core reaction rate distributions, but theory umderestimating k{sub eff} by about 1.5% {delta}k/k.
Uniform semiclassical approximation for absorptive scattering systems
International Nuclear Information System (INIS)
Hussein, M.S.; Pato, M.P.
1987-07-01
The uniform semiclassical approximation of the elastic scattering amplitude is generalized to absorptive systems. An integral equation is derived which connects the absorption modified amplitude to the absorption free one. Division of the amplitude into a diffractive and refractive components is then made possible. (Author) [pt
Magnetostatics of the uniformly polarized torus
DEFF Research Database (Denmark)
Beleggia, Marco; De Graef, Marc; Millev, Yonko
2009-01-01
We provide an exhaustive description of the magnetostatics of the uniformly polarized torus and its derivative self-intersecting (spindle) shapes. In the process, two complementary approaches have been implemented, position-space analysis of the Laplace equation with inhomogeneous boundary condit...
Dynamic Uniform Scaling for Multiobjective Genetic Algorithms
DEFF Research Database (Denmark)
Pedersen, Gerulf; Goldberg, D.E.
2004-01-01
Before Multiobjective Evolutionary Algorithms (MOEAs) can be used as a widespread tool for solving arbitrary real world problems there are some salient issues which require further investigation. One of these issues is how a uniform distribution of solutions along the Pareto non-dominated front can...
Improving rooting uniformity in rose cuttings
Telgen, van H.J.; Eveleens-Clark, B.A.; Garcia Victoria, N.
2007-01-01
Studies to improve rooting uniformity of single node stem cuttings for rose are reported. We found that the variation in shoot growth in a young rose crop depended on the variation in root number of the cuttings, which, in turn, was related to the auxin concentration applied to the cutting before
Downsampling Non-Uniformly Sampled Data
Directory of Open Access Journals (Sweden)
Fredrik Gustafsson
2007-10-01
Full Text Available Decimating a uniformly sampled signal a factor D involves low-pass antialias filtering with normalized cutoff frequency 1/D followed by picking out every Dth sample. Alternatively, decimation can be done in the frequency domain using the fast Fourier transform (FFT algorithm, after zero-padding the signal and truncating the FFT. We outline three approaches to decimate non-uniformly sampled signals, which are all based on interpolation. The interpolation is done in different domains, and the inter-sample behavior does not need to be known. The first one interpolates the signal to a uniformly sampling, after which standard decimation can be applied. The second one interpolates a continuous-time convolution integral, that implements the antialias filter, after which every Dth sample can be picked out. The third frequency domain approach computes an approximate Fourier transform, after which truncation and IFFT give the desired result. Simulations indicate that the second approach is particularly useful. A thorough analysis is therefore performed for this case, using the assumption that the non-uniformly distributed sampling instants are generated by a stochastic process.
uniform van die staatspresidentswag - herkoms en tradisie
African Journals Online (AJOL)
A blue uniform was inter alia proposed in 1980 but finally rejected by the Prime Minister in 1984. Instructions were issued to put forth new ideas. All the arguments in ..... In 1896 Is die rang van kommandant van die Staatsartlllerie verhoog tot die van lultenant-kolonel. Henning Pretorlus, father and first commandant of the.
International Nuclear Information System (INIS)
Guhr, H.; Buettner, O.; Dreyer, U.; Krebs, D.; Spott, D.; Suhr, U.; Weber, E.
1993-01-01
The data (concentrations, pollution loads) measured for the 566 km flowing stretch of the river Elbe on the territory of the former GDR were compiled and evaluated according to primary statistical aspects. The longitudinal section was prepared for major variables with regard to the flow for Q50% and Q5%. The distribution of concentration in various measuring points was shown by means of box plots. Interdependencies between concentration and flow as well as water temperature were investigated and used for assessing diffuse matter input. In addition to determining the saprobic index, the biological control of water pollution comprised the assessment of the macrozoobenthos in the area of sewage discharge, chlorophyll measurements, and inventory of the fish population, analysis of pollutant accumulation in fish and in zoobenthos as well as virus detection. The water quality of the river Elbe was evaluated in compliance with the binding E.C. guidelines and national regulations/recommendations revealing an extreme pollution level which impairs or excludes various utilizations of the Elbe water. (orig.) [de
Dose sculpting with generalized equivalent uniform dose
International Nuclear Information System (INIS)
Wu Qiuwen; Djajaputra, David; Liu, Helen H.; Dong Lei; Mohan, Radhe; Wu, Yan
2005-01-01
With intensity-modulated radiotherapy (IMRT), a variety of user-defined dose distribution can be produced using inverse planning. The generalized equivalent uniform dose (gEUD) has been used in IMRT optimization as an alternative objective function to the conventional dose-volume-based criteria. The purpose of this study was to investigate the effectiveness of gEUD optimization to fine tune the dose distributions of IMRT plans. We analyzed the effect of gEUD-based optimization parameters on plan quality. The objective was to determine whether dose distribution to selected structures could be improved using gEUD optimization without adversely altering the doses delivered to other structures, as in sculpting. We hypothesized that by carefully defining gEUD parameters (EUD 0 and n) based on the current dose distributions, the optimization system could be instructed to search for alternative solutions in the neighborhood, and we could maintain the dose distributions for structures already satisfactory and improve dose for structures that need enhancement. We started with an already acceptable IMRT plan optimized with any objective function. The dose distribution was analyzed first. For structures that dose should not be changed, a higher value of n was used and EUD 0 was set slightly higher/lower than the EUD value at the current dose distribution for critical structures/targets. For structures that needed improvement in dose, a higher to medium value of n was used, and EUD 0 was set to the EUD value or slightly lower/higher for the critical structure/target at the current dose distribution. We evaluated this method in one clinical case each of head and neck, lung and prostate cancer. Dose volume histograms, isodose distributions, and relevant tolerance doses for critical structures were used for the assessment. We found that by adjusting gEUD optimization parameters, the dose distribution could be improved with only a few iterations. A larger value of n could lead to
Coulomb energy of uniformly charged spheroidal shell systems.
Jadhao, Vikram; Yao, Zhenwei; Thomas, Creighton K; de la Cruz, Monica Olvera
2015-03-01
We provide exact expressions for the electrostatic energy of uniformly charged prolate and oblate spheroidal shells. We find that uniformly charged prolate spheroids of eccentricity greater than 0.9 have lower Coulomb energy than a sphere of the same area. For the volume-constrained case, we find that a sphere has the highest Coulomb energy among all spheroidal shells. Further, we derive the change in the Coulomb energy of a uniformly charged shell due to small, area-conserving perturbations on the spherical shape. Our perturbation calculations show that buckling-type deformations on a sphere can lower the Coulomb energy. Finally, we consider the possibility of counterion condensation on the spheroidal shell surface. We employ a Manning-Oosawa two-state model approximation to evaluate the renormalized charge and analyze the behavior of the equilibrium free energy as a function of the shell's aspect ratio for both area-constrained and volume-constrained cases. Counterion condensation is seen to favor the formation of spheroidal structures over a sphere of equal area for high values of shell volume fractions.
Uniform Gauss-Weight Quadratures for Discrete Ordinate Transport Calculations
International Nuclear Information System (INIS)
Carew, John F.; Hu, Kai; Zamonsky, Gabriel
2000-01-01
Recently, a uniform equal-weight quadrature set, UE n , and a uniform Gauss-weight quadrature set, UG n , have been derived. These quadratures have the advantage over the standard level-symmetric LQ n quadrature sets in that the weights are positive for all orders,and the transport solution may be systematically converged by increasing the order of the quadrature set. As the order of the quadrature is increased,the points approach a uniform continuous distribution on the unit sphere,and the quadrature is invariant with respect to spatial rotations. The numerical integrals converge for continuous functions as the order of the quadrature is increased.The numerical characteristics of the UE n quadrature set have been investigated previously. In this paper, numerical calculations are performed to evaluate the application of the UG n quadrature set in typical transport analyses. A series of DORT transport calculations of the >1-MeV neutron flux have been performed for a set of pressure-vessel fluence benchmark problems. These calculations employed the UG n (n = 8, 12, 16, 24, and 32) quadratures and indicate that the UG n solutions have converged to within ∼0.25%. The converged UG n solutions are found to be comparable to the UE n results and are more accurate than the level-symmetric S 16 predictions
Uniformity testing: assessment of a centralized web-based uniformity analysis system.
Klempa, Meaghan C
2011-06-01
Uniformity testing is performed daily to ensure adequate camera performance before clinical use. The aim of this study is to assess the reliability of Beth Israel Deaconess Medical Center's locally built, centralized, Web-based uniformity analysis system by examining the differences between manufacturer and Web-based National Electrical Manufacturers Association integral uniformity calculations measured in the useful field of view (FOV) and the central FOV. Manufacturer and Web-based integral uniformity calculations measured in the useful FOV and the central FOV were recorded over a 30-d period for 4 cameras from 3 different manufacturers. These data were then statistically analyzed. The differences between the uniformity calculations were computed, in addition to the means and the SDs of these differences for each head of each camera. There was a correlation between the manufacturer and Web-based integral uniformity calculations in the useful FOV and the central FOV over the 30-d period. The average differences between the manufacturer and Web-based useful FOV calculations ranged from -0.30 to 0.099, with SD ranging from 0.092 to 0.32. For the central FOV calculations, the average differences ranged from -0.163 to 0.055, with SD ranging from 0.074 to 0.24. Most of the uniformity calculations computed by this centralized Web-based uniformity analysis system are comparable to the manufacturers' calculations, suggesting that this system is reasonably reliable and effective. This finding is important because centralized Web-based uniformity analysis systems are advantageous in that they test camera performance in the same manner regardless of the manufacturer.
24 CFR 5.801 - Uniform financial reporting standards.
2010-04-01
... 24 Housing and Urban Development 1 2010-04-01 2010-04-01 false Uniform financial reporting... and Urban Development GENERAL HUD PROGRAM REQUIREMENTS; WAIVERS Uniform Financial Reporting Standards § 5.801 Uniform financial reporting standards. (a) Applicability. This subpart H implements uniform...
Non-uniform tube representation of proteins
DEFF Research Database (Denmark)
Hansen, Mikael Sonne
Treating the full protein structure is often neither computationally nor physically possible. Instead one is forced to consider various reduced models capturing the properties of interest. Previous work have used tubular neighborhoods of the C-alpha backbone. However, assigning a unique radius...... might not correctly capture volume exclusion - of crucial importance when trying to understand a proteins $3$d-structure. We propose a new reduced model treating the protein as a non-uniform tube with a radius reflecting the positions of atoms. The tube representation is well suited considering X......-ray crystallographic resolution ~ 3Å while a varying radius accounts for the different sizes of side chains. Such a non-uniform tube better capture the protein geometry and has numerous applications in structural/computational biology from the classification of protein structures to sequence-structure prediction....
Casimir energy for a piecewise uniform string
International Nuclear Information System (INIS)
Brevik, I.; Nielsen, H.B.
1989-07-01
The Casimir energy for the transverse oscillations of a piecewise uniform closed string is calculated. The string consists of two parts I and II, endowed in general with different tensions and mass densities, although adjusted in such a way that the velocity of sound always equals the velocity of light. The dispersion equation is worked out under general conditions, and the frequency spectrum is determined in special cases. When the ratio L II /L I between the string lengths is an integer, it is in principle possible to determine the frequency spectrum through solving algebraic equations of increasingly high degree. The Casimir energy relative to the uniform string is in general found to be negative, although in the special case L I =L II the energy is equal to zero. Delicate points in the regularization procedure are discussed; they point toward an anomaly in the theory. (orig.)
Uniform analytic approximation of Wigner rotation matrices
Hoffmann, Scott E.
2018-02-01
We derive the leading asymptotic approximation, for low angle θ, of the Wigner rotation matrix elements, dm1m2 j(θ ) , uniform in j, m1, and m2. The result is in terms of a Bessel function of integer order. We numerically investigate the error for a variety of cases and find that the approximation can be useful over a significant range of angles. This approximation has application in the partial wave analysis of wavepacket scattering.
Physical optics in a uniform gravitational field
Hacyan, Shahen
2012-01-01
The motion of a (quasi-)plane wave in a uniform gravitational field is studied. It is shown that the energy of an elliptically polarized wave does not propagate along a geodesic, but in a direction that is rotated with respect to the gravitational force. The similarity with the walk-off effect in anisotropic crystals or the optical Magnus effect in inhomogeneous media is pointed out.
Sudden cardiac arrest in sports - need for uniform registration
DEFF Research Database (Denmark)
Solberg, E E; Borjesson, M; Sharma, S
2016-01-01
, the importance of gender, ethnicity and age of the athlete, as well as the type and level of sporting activity. A precise instruction for autopsy practice in the case of a SCD of athletes is given, including the role of molecular samples and evaluation of possible doping. Rational decisions about cardiac...... preparticipation screening and cardiac safety at sport facilities requires increased data quality concerning incidence, aetiology and management of SCA/SCD in sports. Uniform standard registration of SCA/SCD in athletes and leisure sportsmen would be a first step towards this goal....
2013-08-19
... Organization (HMO) Benefit--Prime Enrollment Fee Exemption for Survivors of Active Duty Deceased Sponsors and... Enrollment Fee Exemption for Survivors of Active Duty Deceased Sponsors and Medically Retired Uniformed Services [[Page 50360
Uniformity: The key to better inventory management
International Nuclear Information System (INIS)
Boshears, G.
1993-01-01
The objective of this paper is to show how uniformity in describing parts and materials can be the key ingredient to more effective inventory management. Although most nuclear utilities have some type of computer system for maintenance management as well as materials tracking, few have a system to provide the various users with complete information about parts and material in stock. One of the industry's most perplexing problems is How do you know, and find, the item you need to repair a particular piece of equipment or component? In many instances it is easier to order a new one from the manufacturer rather than try to find it on-site, which can result in inaccurate usage records, over-stocking, frustration, and strain on cash flow. What is needed is a higher degree of uniformity within a station, and a utility, of catalog descriptions for parts and material that will satisfy all users-planners, craftsmen, warehouse personnel, and buyers. The results of attaining this uniformity are improved performance through searchability, duplicate stock avoidance, interchangeability, substitutability, and more accurate bills of material; economic benefits will also be noted
The analysis of colour uniformity for a volumetric display based on a rotating LED array
International Nuclear Information System (INIS)
Wu, Jiang; Liu, Xu; Yan, Caijie; Xia, XinXing; Li, Haifeng
2011-01-01
There is a colour nonuniformity zone existing in three-dimensional (3D) volumetric displays which is based on the rotating colour light-emitting diode (LED) array. We analyse the reason for the colour nonuniformity zone by measuring the light intensity distribution and chromaticity coordinates of the LED in the volumetric display. Two boundaries of the colour nonuniformity zone are calculated. We measure the colour uniformities for a single cuboid of 3*3*4 voxels to display red, green, blue and white colour in different horizontal viewing angles, and for 64 cuboids distributed in the whole cylindrical image space with a fixed viewpoint. To evaluate the colour uniformity of a 3D image, we propose three evaluation indices of colour uniformity: the average of colour difference, the maximum colour difference and the variance of colour difference. The measurement results show that the character of colour uniformity is different for the 3D volumetric display and the two-dimensional display
Temperature uniformity in the CERN CLOUD chamber
Directory of Open Access Journals (Sweden)
A. Dias
2017-12-01
Full Text Available The CLOUD (Cosmics Leaving OUtdoor Droplets experiment at CERN (European Council for Nuclear Research investigates the nucleation and growth of aerosol particles under atmospheric conditions and their activation into cloud droplets. A key feature of the CLOUD experiment is precise control of the experimental parameters. Temperature uniformity and stability in the chamber are important since many of the processes under study are sensitive to temperature and also to contaminants that can be released from the stainless steel walls by upward temperature fluctuations. The air enclosed within the 26 m3 CLOUD chamber is equipped with several arrays (strings of high precision, fast-response thermometers to measure its temperature. Here we present a study of the air temperature uniformity inside the CLOUD chamber under various experimental conditions. Measurements were performed under calibration conditions and run conditions, which are distinguished by the flow rate of fresh air and trace gases entering the chamber at 20 and up to 210 L min−1, respectively. During steady-state calibration runs between −70 and +20 °C, the air temperature uniformity is better than ±0.06 °C in the radial direction and ±0.1 °C in the vertical direction. Larger non-uniformities are present during experimental runs, depending on the temperature control of the make-up air and trace gases (since some trace gases require elevated temperatures until injection into the chamber. The temperature stability is ±0.04 °C over periods of several hours during either calibration or steady-state run conditions. During rapid adiabatic expansions to activate cloud droplets and ice particles, the chamber walls are up to 10 °C warmer than the enclosed air. This results in temperature differences of ±1.5 °C in the vertical direction and ±1 °C in the horizontal direction, while the air returns to its equilibrium temperature with a time constant of about 200 s.
Tomographical properties of uniformly redundant arrays
International Nuclear Information System (INIS)
Cannon, T.M.; Fenimore, E.E.
1978-01-01
Recent work in coded aperture imaging has shown that the uniformly redundant array (URA) can image distant planar radioactive sources with no artifacts. The performance of two URA apertures when used in a close-up tomographic imaging system is investigated. It is shown that a URA based on m sequences is superior to one based on quadratic residues. The m sequence array not only produces less obnoxious artifacts in tomographic imaging, but is also more resilient to some described detrimental effects of close-up imaging. It is shown that in spite of these close-up effects, tomographic depth resolution increases as the source is moved closer to the detector
SAM revisited: uniform semiclassical approximation with absorption
International Nuclear Information System (INIS)
Hussein, M.S.; Pato, M.P.
1986-01-01
The uniform semiclassical approximation is modified to take into account strong absorption. The resulting theory, very similar to the one developed by Frahn and Gross is used to discuss heavy-ion elastic scattering at intermediate energies. The theory permits a reasonably unambiguos separation of refractive and diffractive effects. The systems 12 C+ 12 C and 12 C+ 16 O, which seem to exhibit a remnant of a nuclear rainbow at E=20 Mev/N, are analysed with theory which is built directly on a model for the S-matrix. Simple relations between the fit S-matrix and the underlying complex potential are derived. (Author) [pt
Angular momentum conservation for uniformly expanding flows
International Nuclear Information System (INIS)
Hayward, Sean A
2007-01-01
Angular momentum has recently been defined as a surface integral involving an axial vector and a twist 1-form, which measures the twisting around the spacetime due to a rotating mass. The axial vector is chosen to be a transverse, divergence-free, coordinate vector, which is compatible with any initial choice of axis and integral curves. Then a conservation equation expresses the rate of the change of angular momentum along a uniformly expanding flow as a surface integral of angular momentum densities, with the same form as the standard equation for an axial Killing vector, apart from the inclusion of an effective energy tensor for gravitational radiation
Nonimaging reflectors for efficient uniform illumination.
Gordon, J M; Kashin, P; Rabl, A
1992-10-01
Nonimaging reflectors that are an extension of the design principle that was developed for compound parabolic concentrator type devices are proposed for illumination applications. The optical designs presented offer maximal lighting efficiency while they retain sharp angular control of the radiation and highly uniform flux densities on distant target planes. Our results are presented for symmetrical configurations in two dimensions (troughlike reflectors) for flat and for tubular sources. For fields of view of practical interest (half-angle in the 30-60 degrees range), these devices can achieve minimum-tomaximum intensity ratios of 0.7, while they remain compact and incur low reflective losses.
Formation of Uniform Hollow Silica microcapsules
Yan, Huan; Kim, Chanjoong
2013-03-01
Microcapsules are small containers with diameters in the range of 0.1 - 100 μm. Mesoporous microcapsules with hollow morphologies possess unique properties such as low-density and high encapsulation capacity, while allowing controlled release by permeating substances with a specific size and chemistry. Our process is a one-step fabrication of monodisperse hollow silica capsules with a hierarchical pore structure and high size uniformity using double emulsion templates obtained by the glass-capillary microfluidic technique to encapsulate various active ingredients. These hollow silica microcapsules can be used as biomedical applications such as drug delivery and controlled release.
A uniform Tauberian theorem in dynamic games
Khlopin, D. V.
2018-01-01
Antagonistic dynamic games including games represented in normal form are considered. The asymptotic behaviour of value in these games is investigated as the game horizon tends to infinity (Cesàro mean) and as the discounting parameter tends to zero (Abel mean). The corresponding Abelian-Tauberian theorem is established: it is demonstrated that in both families the game value uniformly converges to the same limit, provided that at least one of the limits exists. Analogues of one-sided Tauberian theorems are obtained. An example shows that the requirements are essential even for control problems. Bibliography: 31 titles.
Uniformly bounded representations of the Lorentz groups
International Nuclear Information System (INIS)
Brega, A.O.
1982-01-01
For the Lorentz group G = SO/sub e/(n + 1, 1)(ngreater than or equal to 2) the author constructs a family of uniformly bounded representations by means of analytically continuing a certain normalization of the unitary principal series. The method the author uses relies on an analysis of various operators under a Mellin transform and extends earlier work of E.N. Wilson. In a series of papers Kunze and Stein initiated the theory of uniformly bounded representations of semisimple Lie groups; the starting point is the unitary principal series T(sigma,s) obtained in a certain subgroup M of G and a purely imaginary number s. From there Kunze and Stein constructed families of representations R(sigma,s) depending analytically on a parameter s in a domain D of C containing the imaginary axis which are unitarily equilvalent to T(sigma,s) for s contained in the set of imaginary numbers and whose operator norms are uniformly bounded for each s in D. In the case of the Lorentz groups SO/sub e/(n + 1, 1)(ngreater than or equal to2) and the trivial representation 1 of M, E.N. Wilson obtained such a family R(1,s) for the domain D = [s contained in the set of C: absolute value Re(s) Vertical Bar2]. For this domain D and for any representation sigma of M the author provides a family R(sigma,s) of uniformly bounded representations analytically continuing T(sigma,s), thereby generalizing Wilson's work. The author has also investigated certain symmetry properties of the representations R(sigma,s) under the action of the Weyl group. The trivial representation is Weyl group invariant and the family R(1,s) obtained by Wilson satisfies R(1,s) = R(1,-s) reflecting this. Obtained was the analogous result R(sigma,s) = R(sigma,-s) for some well known representations sigma that are Weyl group invariant. This involves the explicit computation of certain constants arising in the Fourier transforms of intertwining operators
Apparatus for uniform pumping of lasing media
International Nuclear Information System (INIS)
Condit, W.C.; Eccles, S.F.
1975-01-01
Electron beam pumping of gaseous or liquid lasing media is carried out by means of electron pulses generated by an electron accelerator. Between the accelerator and the laser cavity, the electron pulse is subjected to a magnetic field to turn the electron pulse approximately through a quarter orbit, so that in essence the direction of pulse travel is changed from axial to lateral. This procedure then enables pumping of the laser cavity uniformly and simultaneously, or in any desired traveling wave mode, over the entire length of the laser cavity with relatively short, and highly intense, electron pulses. (U.S.)
A stability criterion for HNFDE with non-uniform delays
International Nuclear Information System (INIS)
Liu Xingwen; Zhong Shouming; Zhang Fengli
2005-01-01
Stability of functional differential equations (FDE) is an increasingly important problem in both science and engineering. Delays, whether uniform or non-uniform, play an important role in the dynamics of a system. Since non-uniform delay is more general and less focused than uniform delay, this paper concentrates on the stability of high-order neutral functional differential equations (HNFDE) with non-uniform delay, and proposes a sufficient condition for it. This result may be widely helpful, thanks to the frequent emergence of a HNFDE with non-uniform delay in various fields. Its effectiveness is illustrated by some examples
Long GRBs sources population non-uniformity
Arkhangelskaja, Irene
Long GRBs observed in the very wide energy band. It is possible to separate two subsets of GRBs with high energy component (E > 500 MeV) presence. First type events energy spectra in low and high energy intervals are similar (as for GRB 021008) and described by Band, power law or broken power law models look like to usual bursts without emission in tens MeV region. For example, Band spectrum of GRB080916C covering 6 orders of magnitude. Second ones contain new additional high energy spectral component (for example, GRB 050525B and GRB 090902B). Both types of GRBs observed since CGRO mission beginning. The low energy precursors existence are typical for all types bursts. Both types of bursts temporal profiles can be similar in the various energy regions during some events or different in other cases. The absence of hard to soft evolution in low energy band and (or) presence of high energy precursors for some events are the special features of second class of GRBs by the results of preliminary data analysis and this facts gives opportunities to suppose differences between these two GRBs subsets sources. Also the results of long GRB redshifts distribution analysis have shown its shape contradiction to uniform population objects one for our Metagalaxy to both total and various redshifts definition methods GRBs sources samples. These evidences allow making preliminary conclusion about non-uniformity of long GRBs sources population.
Mass Production Tools and Process Readiness for Uniform Parts—Injection Molding Application
DEFF Research Database (Denmark)
Boorla, Srinivasa Murthy; Eifler, Tobias; Howard, Thomas J.
2017-01-01
A mass production always aims to produce uniform performing products. Production tools such as pressing dies, casting dies and injection moulds, play a significant role by producing uniform parts for achieving final products. Tool complexity increases when multiple cavities are present. These tools...... pass through several stages of quality maturation, before starting production, where the tool capability for part uniformity can be assessed, corrected and aligned to mass production variables. This research article describes the process of systematic understanding of the impact of variables...... and of finding opportunities to counter them. Application is assessed over a hypothetical plastic injection mould and found feasible. Proposed process could evaluate the tool capability for producing uniform parts, at its digital design verification and its physical validation....
Experimental study on the CHF in uniformly and non-uniformly heated vertical annuli
Energy Technology Data Exchange (ETDEWEB)
Chun, Se Young; Moon, Sang Ki; Chung, Heung June; Park, Jong Kuk; Kim, Bok Deuk; Youn, Young Jung; Chung, Moon Ki
2001-09-01
Up to now, KAERI has performed critical heat flux experiments in water under zero-flow and low-flow conditions using a RCS CHF loop facility with uniformly and non-uniformly heated vertical annulus. Since the existing CHF experiments were mainly performed under low-pressure conditions, we performed the CHF experiment to investigate the pressure effect on the CHF under zero-flow and low-flow conditions for a wide range of system pressures. Also, two vertical annuli with the same geometry have been used to investigate the axial heat flux distributions on the CHF. This report summarizes the experimental results and provides the CHF data that can be used for the development for CHF correlation and a thermal hydraulic analysis code. The CHF data have been collected for system pressures ranging from 0.57 to 15.15 MPa, mass flux 0 and from 200 to 650 kg/m2s, inlet subcooling from 75 to 360 kJ/kg and exit quality from 0.07 to 0.57. At low-flow conditions, the total number of data are 242 and 290 with uniformly heated- and non-uniformly heated test sections, respectively. 41 and 94 CHF data are generated with uniformly heated- and non-uniformly heated test sections, respectively, in zero-flow CHF experiments that are performed by blocking test section bottoms. The CHF experiment result shows that the effects of system pressure, mass flux and inlet subcooling are consistent with conventional understandings and similar to those for round tubes. The behavior of the CHF is relatively complex at low pressures. Also, the effects of axial heat flux profile are large at low-pressure conditions.
Experimental study on the CHF in uniformly and non-uniformly heated vertical annuli
International Nuclear Information System (INIS)
Chun, Se Young; Moon, Sang Ki; Chung, Heung June; Park, Jong Kuk; Kim, Bok Deuk; Youn, Young Jung; Chung, Moon Ki
2001-09-01
Up to now, KAERI has performed critical heat flux experiments in water under zero-flow and low-flow conditions using a RCS CHF loop facility with uniformly and non-uniformly heated vertical annulus. Since the existing CHF experiments were mainly performed under low-pressure conditions, we performed the CHF experiment to investigate the pressure effect on the CHF under zero-flow and low-flow conditions for a wide range of system pressures. Also, two vertical annuli with the same geometry have been used to investigate the axial heat flux distributions on the CHF. This report summarizes the experimental results and provides the CHF data that can be used for the development for CHF correlation and a thermal hydraulic analysis code. The CHF data have been collected for system pressures ranging from 0.57 to 15.15 MPa, mass flux 0 and from 200 to 650 kg/m2s, inlet subcooling from 75 to 360 kJ/kg and exit quality from 0.07 to 0.57. At low-flow conditions, the total number of data are 242 and 290 with uniformly heated- and non-uniformly heated test sections, respectively. 41 and 94 CHF data are generated with uniformly heated- and non-uniformly heated test sections, respectively, in zero-flow CHF experiments that are performed by blocking test section bottoms. The CHF experiment result shows that the effects of system pressure, mass flux and inlet subcooling are consistent with conventional understandings and similar to those for round tubes. The behavior of the CHF is relatively complex at low pressures. Also, the effects of axial heat flux profile are large at low-pressure conditions
Design techniques and measured performance for a uniformly-pumped 4-cm diameter rod amplifier
International Nuclear Information System (INIS)
Linford, G.J.; Yarema, S.M.
1976-01-01
A solid-state laser rod amplifier of moderate aperture achieving a high degree of spatial gain uniformity has been constructed and its performance evaluated. Digital and analogue techniques were used to optimize the amplifier design for performance in a laser fusion application. Results of simple 2-D computer simulations and experimental evaluations of amplifier performance are presented
Liouville theory and uniformization of four-punctured sphere
Hadasz, Leszek; Jaskolski, Zbigniew
2006-01-01
Few years ago Zamolodchikov and Zamolodchikov proposed an expression for the 4-point classical Liouville action in terms of the 3-point actions and the classical conformal block. In this paper we develop a method of calculating the uniformizing map and the uniformizing group from the classical Liouville action on n-punctured sphere and discuss the consequences of Zamolodchikovs conjecture for an explicit construction of the uniformizing map and the uniformizing group for the sphere with four ...
Determining irrigation distribution uniformity and efficiency for nurseries
R. Thomas Fernandez
2010-01-01
A simple method for testing the distribution uniformity of overhead irrigation systems is described. The procedure is described step-by-step along with an example. Other uses of distribution uniformity testing are presented, as well as common situations that affect distribution uniformity and how to alleviate them.
75 FR 78155 - Uniform Compliance Date for Food Labeling Regulations
2010-12-15
.... FDA-2000-N-0011] Uniform Compliance Date for Food Labeling Regulations AGENCY: Food and Drug... 1, 2014, as the uniform compliance date for food labeling regulations that are issued between... established January 2, 2012, as the uniform compliance date for food labeling regulations issued between...
77 FR 70885 - Uniform Compliance Date for Food Labeling Regulations
2012-11-28
.... FDA-2000-N-0011] Uniform Compliance Date for Food Labeling Regulations AGENCY: Food and Drug... January 1, 2016, as the uniform compliance date for food labeling regulations that are issued between... established January 1, 2014, as the uniform compliance date for food labeling regulations issued between...
Barriers to Implementing a Single Joint Combat Camouflage Uniform
2017-12-01
opportunities, threats (SWOT), and political, economic, social, and technological (PEST) analyses; examines the requirements and role of each of the...SUBJECT TERMS ground combat uniform, combat camouflage uniform history , combat camouflage uniform pattern, camouflage pattern testing 15. NUMBER...methodology applies strengths, weaknesses, opportunities, threats (SWOT), and political, economic, social, and technological (PEST) analyses
On the Invariant Uniform Roe Algebra as Crossed Product
Kankeyanathan Kannan
2013-01-01
The uniform Roe C*-algebra (also called uniform translation)C^*- algebra provides a link between coarse geometry and C^*- algebra theory. The uniform Roe algebra has a great importance in geometry, topology and analysis. We consider some of the elementary concepts associated with coarse spaces.
46 CFR 310.63 - Uniforms and textbooks.
2010-10-01
... 46 Shipping 8 2010-10-01 2010-10-01 false Uniforms and textbooks. 310.63 Section 310.63 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION TRAINING MERCHANT MARINE TRAINING Admission and Training of Midshipmen at the United States Merchant Marine Academy § 310.63 Uniforms and textbooks. The Academy shall supply midshipmen uniforms an...
Instruction sequence based non-uniform complexity classes
Bergstra, J.A.; Middelburg, C.A.
2013-01-01
We present an approach to non-uniform complexity in which single-pass instruction sequences play a key part, and answer various questions that arise from this approach. We introduce several kinds of non-uniform complexity classes. One kind includes a counterpart of the well-known non-uniform
Uniform Suspension of the Clustered Triamcinolone Acetonide Particle
Directory of Open Access Journals (Sweden)
Masahiko Sugimoto
2013-01-01
Full Text Available Purpose. MaQaid (MaQ is a new triamcinolone acetonide commercialised in Japan to visualize the vitreous. Because MaQ is preservative-free, it has a lower risk of ocular toxicities. However, since MaQ is only available as a powder, it needs suspenssion. Suspension does not always result uniformally, which causes poor visibility. This study reports a new MaQ suspension for better visibility. Methods. After medium addition to a MaQ vial, various methods were used. These included the use of (1 vortex mixer, (2 two syringes and a three-way stopcock, and (3 ultrasonic washer. We calculated suspended MaQ concentration (. To evaluate the reproducibility, we estimated the coefficient of variance (CV, . We used this MaQ for pig eyes, and vitreous visualization was simulated. Subsequently, we used this MaQ suspension for humans. Results. MaQ suspensions were sucessfull, and the concentrations of single particles increased significantly (. The CV was 36.1% for the routine method and 9.03% ffor the new method. Administration of a suspended MaQ made it possible to clearly visualize the vitreous in both pig and human eyes. Conclusions. We devised new techniques for uniformal MaQ suspension. These new methods can compensate for the MaQ disadvantages and ensure a safety surgery.
Synthesis of uniform-sized zeolite from windshield waste
International Nuclear Information System (INIS)
Kim, Jae-Chan; Choi, Mingu; Song, Hee Jo; Park, Jung Eun; Yoon, Jin-Ho; Park, Kyung-Soo; Lee, Chan Gi; Kim, Dong-Wan
2015-01-01
We demonstrate the synthesis of A-type zeolite from mechanically milled windshield waste via acid treatment and a low-temperature hydrothermal method. As-received windshield cullet was crushed to a fine powder and impurities were removed by HNO 3 treatment. The resulting glass powder was used as the source material for the hydrothermal synthesis of A-type zeolite. Crystal structure, morphology, and elemental composition changes of the windshield waste were evaluated at each step of the process through scanning electron microscopy, X-ray diffraction, X-ray fluorescence spectrometry, etc. After a high-energy milling process, the glass had an average particle size of 520 nm; after acid treatment, its composition was over 94% silica. Zeolite was successfully synthesized in the A-type phase with a uniform cubic shape. - Highlights: • Environmental-friendly recycling of windshield waste for high valuable product of zeolite. • Synthesis of zeolite form windshield waste via a low-temperature hydrothermal process. • High-energy milling effect on the uniform cubic shape and high-purity A-type zeolite.
Gloss uniformity measurement update for ISO/IEC 19751
Ng, Yee S.; Cui, Chengwu; Kuo, Chunghui; Maggard, Eric; Mashtare, Dale; Morris, Peter
2005-01-01
To address the standardization issues of perceptually based image quality for printing systems, ISO/IEC JTC1/SC28, the standardization committee for office equipment chartered the W1.1 project with the responsibility of drafting a proposal for an international standard for the evaluation of printed image quality1. An ISO draft Standard2, ISO/WD 19751-1, Office Equipment - Appearance-based image quality standards for printers - Part 1: Overview, Procedure and Common Methods, 2004 describes the overview of this multi-part appearance-based image quality standard. One of the ISO 19751 multi-part Standard"s tasks is to address the appearance-based gloss and gloss uniformity issues (in ISO 19751-2). This paper summarizes the current status and technical progress since the last two updates3, 4. In particular, we will be discussion our attempt to include 75 degree gloss (G75) objective measurement5 in differential gloss and within-page gloss uniformity. The result for a round-robin experiment involving objective measurement of differential gloss using G60 and G75 gloss measurement geometry is described. The results for two perceptual-based round-robin experiments relating to haze effect on the perception of gloss, and gloss artifacts (gloss streaks/bands, gloss graininess/mottle) are discussed.
Temperature distribution in a uniformly moving medium
International Nuclear Information System (INIS)
Mitchell, Joseph D; Petrov, Nikola P
2009-01-01
We apply several physical ideas to determine the steady temperature distribution in a medium moving with uniform velocity between two infinite parallel plates. We compute it in the coordinate frame moving with the medium by integration over the 'past' to account for the influence of an infinite set of instantaneous point sources of heat in past moments as seen by an observer moving with the medium. The boundary heat flux is simulated by appropriately distributed point heat sources on the inner side of an adiabatically insulating boundary. We make an extensive use of the Green functions with an emphasis on their physical meaning. The methodology used in this paper is of great pedagogical value as it offers an opportunity for students to see the connection between powerful mathematical techniques and their physical interpretation in an intuitively clear physical problem. We suggest several problems and a challenging project that can be easily incorporated in undergraduate or graduate courses
Uniform LED illuminator for miniature displays
Medvedev, Vladimir; Pelka, David G.; Parkyn, William A.
1998-10-01
The Total Internally Reflecting (TIR) lens is a faceted structure composed of prismatic elements that collect a source's light over a much larger angular range than a conventional Fresnel lens. It has been successfully applied to the efficient collimation of light from incandescent and fluorescent lamps, and from light-emitting diodes (LEDs). A novel LED-powered collimating backlight is presented here, for uniformly illuminating 0.25'-diagonal miniature liquid- crystal displays, which are a burgeoning market for pagers, cellular phones, digital cameras, camcorders, and virtual- reality displays. The backlight lens consists of a central dual-asphere refracting section and an outer TIR section, properly curved with a curved exit face.
Density Fluctuations in Uniform Quantum Gases
International Nuclear Information System (INIS)
Bosse, J.; Pathak, K. N.; Singh, G. S.
2011-01-01
Analytical expressions are given for the static structure factor S(k) and the pair correlation function g(r) for uniform ideal Bose-Einstein and Fermi-Dirac gases for all temperatures. In the vicinity of Bose Einstein condensation (BEC) temperature, g(r) becomes long ranged and remains so in the condensed phase. In the dilute gas limit, g(r) of bosons and fermions do not coincide with Maxwell-Boltzmann gas but exhibit bunching and anti-bunching effect respectively. The width of these functions depends on the temperature and is scaled as √(inverse atomic mass). Our numerical results provide the precise quantitative values of suppression/increase (antibunching and bunching) of the density fluctuations at small distances in ideal quantum gases in qualitative agreement with the experimental observation for almost non-trapped dilute gases.
Memory effect in uniformly heated granular gases
Trizac, E.; Prados, A.
2014-07-01
We evidence a Kovacs-like memory effect in a uniformly driven granular gas. A system of inelastic hard particles, in the low density limit, can reach a nonequilibrium steady state when properly forced. By following a certain protocol for the drive time dependence, we prepare the gas in a state where the granular temperature coincides with its long time value. The temperature subsequently does not remain constant but exhibits a nonmonotonic evolution with either a maximum or a minimum, depending on the dissipation and on the protocol. We present a theoretical analysis of this memory effect at Boltzmann-Fokker-Planck equation level and show that when dissipation exceeds a threshold, the response can be called anomalous. We find excellent agreement between the analytical predictions and direct Monte Carlo simulations.
Optimization of overlap uniformness for ptychography.
Huang, Xiaojing; Yan, Hanfei; Harder, Ross; Hwu, Yeukuang; Robinson, Ian K; Chu, Yong S
2014-05-19
We demonstrate the advantages of imaging with ptychography scans that follow a Fermat spiral trajectory. This scan pattern provides a more uniform coverage and a higher overlap ratio with the same number of scan points over the same area than the presently used mesh and concentric [13] patterns. Under realistically imperfect measurement conditions, numerical simulations show that the quality of the reconstructed image is improved significantly with a Fermat spiral compared with a concentric scan pattern. The result is confirmed by the performance enhancement with experimental data, especially under low-overlap conditions. These results suggest that the Fermat spiral pattern increases the quality of the reconstructed image and tolerance to data with imperfections.
2008-11-13
ABSTRACT (Maximum 200 Words) The DLA and DSCP sponsored Customer Driven Uniform Manufacturing (CDUM) program’s primary goals are to reduce total...functions that make decisions or consume apparel items. PDIT’s CDUM assignments were to create the web accessible database, create decision support tools...Manufacturing Monitoring Processes ....................................................40 Figure 32 – Assign Contract to Buyer
Viadero, Debra
2005-01-01
This article reports on the effectiveness of school uniform policies. At Stephen Decatur Middle School, it is the school's policy that all students wear the standard school attire consisting of khaki pants with polo shirts in white, burgundy, or navy blue. Some of the shirts also sport an embroidered Decatur eagle, an optional embellishment.…
On The Dynamic Analysis of Non-Uniform Beams Under Uniformly ...
African Journals Online (AJOL)
... the non-uniform continuous beam was replaced by a non-continuous (discrete) system made up of beam elements. The modified elemental and overall stiffness, and mass matrices, the elemental and overall centripetal acceleration matrices as well as the load vector were derived. Next, the Newmark's direct integration ...
Politicas de uniformes y codigos de vestuario (Uniforms and Dress-Code Policies). ERIC Digest.
Lumsden, Linda
This digest in Spanish examines schools' dress-code policies and discusses the legal considerations and research findings about the effects of such changes. Most revisions to dress codes involve the use of uniforms, typically as a way to curb school violence and create a positive learning environment. A recent survey of secondary school principals…
Dynamic thermoelectricity in uniform bipolar semiconductor
Energy Technology Data Exchange (ETDEWEB)
Volovichev, I.N., E-mail: vin@ire.kharkov.ua
2016-07-01
The theory of the dynamic thermoelectric effect has been developed. The effect lies in an electric current flowing in a closed circuit that consists of a uniform bipolar semiconductor, in which a non-uniform temperature distribution in the form of the traveling wave is created. The calculations are performed for the one-dimensional model in the quasi-neutrality approximation. It was shown that the direct thermoelectric current prevails, despite the periodicity of the thermal excitation, the circuit homogeneity and the lack of rectifier properties of the semiconductor system. Several physical reasons underlining the dynamic thermoelectric effect are found. One of them is similar to the Dember photoelectric effect, its contribution to the current flowing is determined by the difference in the electron and hole mobilities, and is completely independent of the carrier Seebeck coefficients. The dependence of the thermoelectric short circuit current magnitude on the semiconductor parameters, as well as on the temperature wave amplitude, length and velocity is studied. It is shown that the magnitude of the thermoelectric current is proportional to the square of the temperature wave amplitude. The dependence of the thermoelectric short circuit current on the temperature wave length and velocity is the nonmonotonic function. The optimum values for the temperature wave length and velocity, at which the dynamic thermoelectric effect is the greatest, have been deduced. It is found that the thermoelectric short circuit current changes its direction with decreasing the temperature wave length under certain conditions. The prospects for the possible applications of the dynamic thermoelectric effect are also discussed.
Directory of Open Access Journals (Sweden)
Julián Loboa
2011-12-01
,5% (qualificação boa, e o desem- penho menos eficiente o apresentou a fita de irrigação.Unconventional filtration technologies based on the upward flow of water through filters with layers of materials with different grain sizes are used to evaluate the coefficients of uniformity in four irrigation modules of high frequency in water treatment plant at the Research Institute Cinara in Cali. Each module uses different irrigation emitters: Microjet, built-loaded (Aqua-Traxx, Lyn, and irrigation tape (Queen Gil. Under this system of filtration is obtained that the irrigation emitters that achieve the best data of the coefficients of uniformity were Microjet (94.3% and Lyn (93.73%, taking account a period between over 120 to 165 hours respectively. In a time of 72 hours of continuous irrigation, the system that showed a more homogenous uniformity coefficient was the module with the Lyn emitters which reached the values of 91.5 (rated good and the lowest performance was the module with the irrigation tape.
Tablet splitting and weight uniformity of half-tablets of 4 medications in pharmacy practice.
Tahaineh, Linda M; Gharaibeh, Shadi F
2012-08-01
Tablet splitting is a common practice for multiple reasons including cost savings; however, it does not necessarily result in weight-uniform half-tablets. To determine weight uniformity of half-tablets resulting from splitting 4 products available in the Jordanian market and investigate the effect of tablet characteristics on weight uniformity of half-tablets. Ten random tablets each of warfarin 5 mg, digoxin 0.25 mg, phenobarbital 30 mg, and prednisolone 5 mg were weighed and split by 6 PharmD students using a knife. The resulting half-tablets were weighed and evaluated for weight uniformity. Other relevant physical characteristics of the 4 products were measured. The average tablet hardness of the sampled tablets ranged from 40.3 N to 68.9 N. Digoxin, phenobarbital, and prednisolone half-tablets failed the weight uniformity test; however, warfarin half-tablets passed. Digoxin, warfarin, and phenobarbital tablets had a score line and warfarin tablets had the deepest score line of 0.81 mm. Splitting warfarin tablets produces weight-uniform half-tablets that may possibly be attributed to the hardness and the presence of a deep score line. Digoxin, phenobarbital, and prednisolone tablet splitting produces highly weight variable half-tablets. This can be of clinical significance in the case of the narrow therapeutic index medication digoxin.
Stakeholder Perceptions of Cyberbullying Cases: Application of the Uniform Definition of Bullying.
Moreno, Megan A; Suthamjariya, Nina; Selkie, Ellen
2018-04-01
The Uniform Definition of Bullying was developed to address bullying and cyberbullying, and to promote consistency in measurement and policy. The purpose of this study was to understand community stakeholder perceptions of typical cyberbullying cases, and to evaluate how these case descriptions align with the Uniform Definition. In this qualitative case analysis we recruited stakeholders commonly involved in cyberbullying. We used purposeful sampling to identify and recruit adolescents and young adults, parents, and professionals representing education and health care. Participants were asked to write a typical case of cyberbullying and descriptors in the context of a group discussion. We applied content analysis to case excerpts using inductive and deductive approaches, and chi-squared tests for mixed methods analyses. A total of 68 participants contributed; participants included 73% adults and 27% adolescents and young adults. A total of 650 excerpts were coded from participants' example cases and 362 (55.6%) were consistent with components of the Uniform Definition. The most frequently mentioned component of the Uniform Definition was Aggressive Behavior (n = 218 excerpts), whereas Repeated was mentioned infrequently (n = 19). Most participants included two to three components of the Uniform Definition within an example case; none of the example cases included all components of the Uniform Definition. We found that most participants described cyberbullying cases using few components of the Uniform Definition. Findings can be applied toward considering refinement of the Uniform Definition to ensure stakeholders find it applicable to cyberbullying. Copyright © 2017 The Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.
Influencing factors of GaN growth uniformity through orthogonal test analysis
International Nuclear Information System (INIS)
Zhang, Zhi; Fang, Haisheng; Yan, Han; Jiang, Zhimin; Zheng, Jiang; Gan, Zhiyin
2015-01-01
Gallium nitride (GaN) is widely used in light-emitting diode (LED) devices due to its wide bandgap and excellently optoelectronic performance. The efficiency and lifetime of LEDs are critically determined by quality of GaN, for example, growth uniformity. Metal-organic chemical vapor deposition (MOCVD) is the most popular technique to grow high-quality GaN epitaxial layers. Growth uniformity is influenced by fluid flow, heat transfer and chemical reactions in the reactor. In this paper, the growth process in a close-coupled showerhead (CCS) MOCVD reactor is investigated based on 3D numerical simulation. Influences of the operating parameters on the growth uniformity are presented. To evaluate the role of the parameters systematically and efficiently on the growth uniformity, orthogonal test method is introduced. The results reveal that the growth rate and uniformity are strongly related to the total gas flow rate, the showerhead height and the inlet gas temperature, but are weakly affected by the isothermal wall temperature, the rotating speed and the susceptor temperature under the ranges of the current study. The optimized combination of the parameters is further proposed as a useful reference for obtaining the LED layers with a balance between the growth rate and the growth uniformity in industry. - Highlights: • Fluid flow, heat transfer, chemical reactions are calculated for a 3D CCS reactor. • The effects of process parameters on growth rate and uniformity are investigated. • Orthogonal test method is introduced to analyze the effect of multi-factors. • Optimal combinations can be obtained for the best growth rate and uniformity.
Decomposed Photo Response Non-Uniformity for Digital Forensic Analysis
Li, Yue; Li, Chang-Tsun
The last few years have seen the applications of Photo Response Non-Uniformity noise (PRNU) - a unique stochastic fingerprint of image sensors, to various types of digital forensic investigations such as source device identification and integrity verification. In this work we proposed a new way of extracting PRNU noise pattern, called Decomposed PRNU (DPRNU), by exploiting the difference between the physical andartificial color components of the photos taken by digital cameras that use a Color Filter Array for interpolating artificial components from physical ones. Experimental results presented in this work have shown the superiority of the proposed DPRNU to the commonly used version. We also proposed a new performance metrics, Corrected Positive Rate (CPR) to evaluate the performance of the common PRNU and the proposed DPRNU.
Analysis of pellet coating uniformity using a computer scanner.
Šibanc, Rok; Luštrik, Matevž; Dreu, Rok
2017-11-30
A fast method for pellet coating uniformity analysis, using a commercial computer scanner was developed. The analysis of the individual particle coating thicknesses was based on using a transparent orange colored coating layer deposited on white pellet cores. Besides the analysis of the coating thickness the information of pellet size and shape was obtained as well. Particle size dependent coating thickness and particle size independent coating variability was calculated by combining the information of coating thickness and pellet size. Decoupling coating thickness variation sources is unique to presented method. For each coating experiment around 10000 pellets were analyzed, giving results with a high statistical confidence. Proposed method was employed for the performance evaluation of classical Wurster and swirl enhanced Wurster coater operated at different gap settings and air flow rates. Copyright © 2017 Elsevier B.V. All rights reserved.
Strain distributions in nano-onions with uniform and non-uniform compositions
International Nuclear Information System (INIS)
Duan, H L; Karihaloo, B L; Wang, J; Yi, X
2006-01-01
Nano-onions are ellipsoidal or spherical particles consisting of a core surrounded by concentric shells of nanometre size. Nano-onions produced by self-assembly and colloidal techniques have different structures and compositions, and thus differ in the state of strains. The mismatch of the thermal expansion coefficients and lattice constants between neighbouring shells induces stress/strain fields in the core and shells, which in turn affect their physical/mechanical properties and/or the properties of the composites containing them. In this paper, the strains in embedded and free-standing nano-onions with uniform and non-uniform compositions are studied in detail. It is found that the strains in the nano-onions can be modified by adjusting their compositions and structures. The results are useful for the band structure engineering of semiconductor nano-onions
Uniform Page Migration Problem in Euclidean Space
Directory of Open Access Journals (Sweden)
Amanj Khorramian
2016-08-01
Full Text Available The page migration problem in Euclidean space is revisited. In this problem, online requests occur at any location to access a single page located at a server. Every request must be served, and the server has the choice to migrate from its current location to a new location in space. Each service costs the Euclidean distance between the server and request. A migration costs the distance between the former and the new server location, multiplied by the page size. We study the problem in the uniform model, in which the page has size D = 1 . All request locations are not known in advance; however, they are sequentially presented in an online fashion. We design a 2.75 -competitive online algorithm that improves the current best upper bound for the problem with the unit page size. We also provide a lower bound of 2.732 for our algorithm. It was already known that 2.5 is a lower bound for this problem.
Seismic signal of near steady uniform flows
Mangeney, A.; Bachelet, V.; Toussaint, R.; de Rosny, J.
2017-12-01
The seismic signal generated by rockfalls, landslides or avalanches is a unique tool to detect, characterize and monitor gravitational flow activity. A major challenge in this domain is to retrieve the dynamic properties of the flow from the emitted seismic signal. In this study, we propose laboratory experiments where the dynamic properties of the flow (velocity, granular temperature, density, etc.) are measured together with the generated seismic signal. We investigate near steady uniform flows made of glass beads of 2mm diameter, flowing throughout a thin rectangular channel of 10 cm width, with tunable tilt angle and height flow, thanks to an adjustable opening gate. The flow is monitored from the spine with a fast camera (5000 fps), and the emitted waves are recorded by accelerometers (10Hz - 54 kHz), stuck on the back side of the bottom of the channel. Among others, three seismic parameters are analyzed: the power radiated by the flow, the mean frequency of the signal, and the modulation of its amplitude. We show that they are linked to three dynamical properties: the mean kinetic energy of the flow, the speed of collisions between beads and the vertical oscillation of the beads, respectively.
Structurally uniform and atomically precise carbon nanostructures
Segawa, Yasutomo; Ito, Hideto; Itami, Kenichiro
2016-01-01
Nanometre-sized carbon materials consisting of benzene units oriented in unique geometric patterns, hereafter named nanocarbons, conduct electricity, absorb and emit light, and exhibit interesting magnetic properties. Spherical fullerene C60, cylindrical carbon nanotubes and sheet-like graphene are representative forms of nanocarbons, and theoretical simulations have predicted several exotic 3D nanocarbon structures. At present, synthetic routes to nanocarbons mainly lead to mixtures of molecules with a range of different structures and properties, which cannot be easily separated or refined into pure forms. Some researchers believe that it is impossible to synthesize these materials in a precise manner. Obtaining ‘pure’ nanocarbons is a great challenge in the field of nanocarbon science, and the construction of structurally uniform nanocarbons, ideally as single molecules, is crucial for the development of functional materials in nanotechnology, electronics, optics and biomedical applications. This Review highlights the organic chemistry approach — more specifically, bottom-up construction with atomic precision — that is currently the most promising strategy towards this end.
Non-uniform versus uniform attenuation correction in brain perfusion SPET of healthy volunteers
International Nuclear Information System (INIS)
Van Laere, K.; Versijpt, J.; Dierckx, R.; Koole, M.
2001-01-01
Although non-uniform attenuation correction (NUAC) can supply more accurate absolute quantification, it is not entirely clear whether NUAC provides clear-cut benefits in the routine clinical practice of brain SPET imaging. The aim of this study was to compare the effect of NUAC versus uniform attenuation correction (UAC) on volume of interest (VOI)-based semi-quantification of a large age- and gender-stratified brain perfusion normal database. Eighty-nine healthy volunteers (46 females and 43 males, aged 20-81 years) underwent standardised high-resolution single-photon emission tomography (SPET) with 925 MBq 99m Tc-ethyl cysteinate dimer (ECD) on a Toshiba GCA-9300A camera with 153 Gd or 99m Tc transmission CT scanning. Emission images were reconstructed by filtered back-projection and scatter corrected using the triple-energy window correction method. Both non-uniform Chang attenuation correction (one iteration) and uniform Sorenson correction (attenuation coefficient 0.09 cm -1 ) were applied. Images were automatically re-oriented to a stereotactic template on which 35 predefined VOIs were defined for semi-quantification (normalisation on total VOI counts). Small but significant differences between relative VOI uptake values for NUAC versus UAC in the infratentorial region were found. VOI standard deviations were significantly smaller for UAC, 4.5% (range 2.6-7.5), than for NUAC, 5.0% (2.3-9.0) (P 99m Tc-ECD uptake values in healthy volunteers to those obtained with NUAC, although values for the infratentorial region are slightly lower. NUAC produces a slight increase in inter-subject variability. Further study is necessary in various patient populations to establish the full clinical impact of NUAC in brain perfusion SPET. (orig.)
Das materialidades da escola: o uniforme escolar On the materialities of school: the school uniform
Directory of Open Access Journals (Sweden)
Ivanir Ribeiro
2012-09-01
Full Text Available Este texto dedica-se a situar o uniforme escolar como objeto histórico e como importante fonte do e no universo escolar. Para tanto, empreende-se uma revisão da literatura que aborda a temática e investe-se em uma reflexão que concebe esse artefato como uma das expressões da materialidade que dá contornos à forma escolar, tomando-o na perspectiva da cultura material. Alguns autores servem aqui de referência: Richard Bucaille, Jean-Marie Pesez e Ulpiano Bezerra de Meneses, nos estudos em que se dedicam à cultura material; Agustín Benito Escolano e Rosa Fátima de Souza, nos trabalhos em que voltam o olhar para cultura material escolar; Inês Dussel e Katiene Nogueira da Silva, autoras que abordam diretamente a questão dos uniformes escolares. Não menos importantes para efeitos deste artigo são os trabalhos que tratam do movimento higienista, particularmente aqueles levados a cabo por José Gondra. Os dados levantados e as reflexões efetuadas indiciam dois movimentos (ou tensões nada desprezíveis. Por um lado, são evidentes as dificuldades encontradas para adoção dos uniformes escolares por todos os alunos, tanto por parte do Estado quanto por parte das famílias, devido ao fato de eles representarem um custo elevado, principalmente os calçados, artigos pouco utilizados pela maioria da população até, no mínimo, meados do século XX. Por outro lado, há indícios de que esse traje desempenhava uma função niveladora importante. Por meio dele, criava-se uma ideia de padronização e democratização do ensino, mesmo que em aparência, além de se dar visibilidade pública a uma instituição social cada vez mais importante: a escola.This text is devoted to situate the school uniform as a historical object, and as an important source on and in the school universe. For that, a literature survey is carried out on this theme, and a reflection is conducted envisaging this artifact as one of the expressions of materiality that
Optimal shortening of uniform covering arrays.
Directory of Open Access Journals (Sweden)
Jose Torres-Jimenez
Full Text Available Software test suites based on the concept of interaction testing are very useful for testing software components in an economical way. Test suites of this kind may be created using mathematical objects called covering arrays. A covering array, denoted by CA(N; t, k, v, is an N × k array over [Formula: see text] with the property that every N × t sub-array covers all t-tuples of [Formula: see text] at least once. Covering arrays can be used to test systems in which failures occur as a result of interactions among components or subsystems. They are often used in areas such as hardware Trojan detection, software testing, and network design. Because system testing is expensive, it is critical to reduce the amount of testing required. This paper addresses the Optimal Shortening of Covering ARrays (OSCAR problem, an optimization problem whose objective is to construct, from an existing covering array matrix of uniform level, an array with dimensions of (N - δ × (k - Δ such that the number of missing t-tuples is minimized. Two applications of the OSCAR problem are (a to produce smaller covering arrays from larger ones and (b to obtain quasi-covering arrays (covering arrays in which the number of missing t-tuples is small to be used as input to a meta-heuristic algorithm that produces covering arrays. In addition, it is proven that the OSCAR problem is NP-complete, and twelve different algorithms are proposed to solve it. An experiment was performed on 62 problem instances, and the results demonstrate the effectiveness of solving the OSCAR problem to facilitate the construction of new covering arrays.
Liquid toroidal drop under uniform electric field
Zabarankin, Michael
2017-06-01
The problem of a stationary liquid toroidal drop freely suspended in another fluid and subjected to an electric field uniform at infinity is addressed analytically. Taylor's discriminating function implies that, when the phases have equal viscosities and are assumed to be slightly conducting (leaky dielectrics), a spherical drop is stationary when Q=(2R2+3R+2)/(7R2), where R and Q are ratios of the phases' electric conductivities and dielectric constants, respectively. This condition holds for any electric capillary number, CaE, that defines the ratio of electric stress to surface tension. Pairam and Fernández-Nieves showed experimentally that, in the absence of external forces (CaE=0), a toroidal drop shrinks towards its centre, and, consequently, the drop can be stationary only for some CaE>0. This work finds Q and CaE such that, under the presence of an electric field and with equal viscosities of the phases, a toroidal drop having major radius ρ and volume 4π/3 is qualitatively stationary-the normal velocity of the drop's interface is minute and the interface coincides visually with a streamline. The found Q and CaE depend on R and ρ, and for large ρ, e.g. ρ≥3, they have simple approximations: Q˜(R2+R+1)/(3R2) and CaE∼3 √{3 π ρ / 2 } (6 ln ρ +2 ln [96 π ]-9 )/ (12 ln ρ +4 ln [96 π ]-17 ) (R+1 ) 2/ (R-1 ) 2.
Impact of uniform electrode current distribution on ETF
Bents, D. J.
1982-01-01
The design impacts on the ETF electrode consolidation network associated with uniform channel electrode current distribution are examined and the alternate consolidation design which occur are presented compared to the baseline (non-uniform current) design with respect to performance, and hardware requirements. A rational basis is given for comparing the requirements for the different designs and the savings that result from uniform current distribution. Performance and cost impacts upon the combined cycle plant are discussed.
Assessment of MODIS RSB Detector Uniformity Using Deep Convective Clouds
Chang, Tiejun; Xiong, Xiaoxiong (Jack); Angal, Amit; Mu, Qiaozhen
2016-01-01
For satellite sensor, the striping observed in images is typically associated with the relative multiple detector gain difference derived from the calibration. A method using deep convective cloud (DCC) measurements to assess the difference among detectors after calibration is proposed and demonstrated for select reflective solar bands (RSBs) of the Moderate Resolution Imaging Spectroradiometer (MODIS). Each detector of MODIS RSB is calibrated independently using a solar diffuser (SD). Although the SD is expected to accurately characterize detector response, the uncertainties associated with the SD degradation and characterization result in inadequacies in the estimation of each detector's gain. This work takes advantage of the DCC technique to assess detector uniformity and scan mirror side difference for RSB. The detector differences for Terra MODIS Collection 6 are less than 1% for bands 1, 3-5, and 18 and up to 2% for bands 6, 19, and 26. The largest difference is up to 4% for band 7. Most Aqua bands have detector differences less than 0.5% except bands 19 and 26 with up to 1.5%. Normally, large differences occur for edge detectors. The long-term trending shows seasonal oscillations in detector differences for some bands, which are correlated with the instrument temperature. The detector uniformities were evaluated for both unaggregated and aggregated detectors for MODIS band 1 and bands 3-7, and their consistencies are verified. The assessment results were validated by applying a direct correction to reflectance images. These assessments can lead to improvements to the calibration algorithm and therefore a reduction in striping observed in the calibrated imagery.
Liouville theory and uniformization of four-punctured sphere
Hadasz, Leszek; Jaskólski, Zbigniew
2006-08-01
A few years ago Zamolodchikov and Zamolodchikov proposed an expression for the four-point classical Liouville action in terms of the three-point actions and the classical conformal block [Nucl. Phys. B 477, 577 (1996)]. In this paper we develop a method of calculating the uniformizing map and the uniformizing group from the classical Liouville action on n-punctured sphere and discuss the consequences of Zamolodchikovs conjecture for an explicit construction of the uniformizing map and the uniformizing group for the sphere with four punctures.
Uniform irradiation of irregularly shaped cavities for photodynamic therapy.
Rem, A I; van Gemert, M J; van der Meulen, F W; Gijsbers, G H; Beek, J F
1997-03-01
It is difficult to achieve a uniform light distribution in irregularly shaped cavities. We have conducted a study on the use of hollow 'integrating' moulds for more uniform light delivery of photodynamic therapy in irregularly shaped cavities such as the oral cavity. Simple geometries such as a cubical box, a sphere, a cylinder and a 'bottle-neck' geometry have been investigated experimentally and the results have been compared with computed light distributions obtained using the 'radiosity method'. A high reflection coefficient of the mould and the best uniform direct irradiance possible on the inside of the mould were found to be important determinants for achieving a uniform light distribution.
14 CFR Section 19 - Uniform Classification of Operating Statistics
2010-01-01
... Statistics Section 19 Section 19 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION... AIR CARRIERS Operating Statistics Classifications Section 19 Uniform Classification of Operating Statistics ...
Problem of uniqueness in the renewal process generated by the uniform distribution
Directory of Open Access Journals (Sweden)
D. Ugrin-parac
1992-01-01
Full Text Available The renewal process generated by the uniform distribution, when interpreted as a transformation of the uniform distribution into a discrete distribution, gives rise to the question of uniqueness of the inverse image. The paper deals with a particular problem from the described domain, that arose in the construction of a complex stochastic test intended to evaluate pseudo-random number generators. The connection of the treated problem with the question of a unique integral representation of Gamma-function is also mentioned.
Preparing Magnetocaloric LaFeSi Uniform Microstructures by Spark Plasma Sintering
DEFF Research Database (Denmark)
Vicente, N.; Ocanã, J.; Neves Bez, Henrique
2014-01-01
Spark Plasma Sintering (SPS) of LaFeSi alloy powders was conducted to prepare magnetocaloric La-Fe-Si-based uniform microstructures. Two electrically insulating discs made of alumina were interposed between the punches and powder sample inhibiting the flow of electric current across the powder...... from hydrogenated and decrypted casting ingot. The characterizations of sintered samples were performed by Scanning Electron Microscopy (SEM), Archimedes principle, Vicker’s hardness and microhardness. The uniformity of the microstructure was evaluated by checking the evidence of position on the Vicker...
An alternative time marker for the study of the uniform and uniformly accelerated movements
Directory of Open Access Journals (Sweden)
Osmar Henrique Moura da Silva
2003-01-01
Full Text Available This work presents a type of time marker set up with materials of low cost for the study of uniform movements as well as those accelerated by gravitacional force. A mechanism used to measure its frequency is coupled to it in order to find the approximate value of the acceleration of the local gravity. The experiment, that is adapted to be used during a kinematics class, can also be presented by the students at a science fair, for being a stimulating factor as it involves the students’ participation in its construction.
Uniform current density and divergence control in high power extraction ion diodes
International Nuclear Information System (INIS)
Desjarlais, M.P.; Coats, R.S.; Lockner, T.R.; Pointon, T.D.; Johnson, D.J.; Slutz, S.A.; Lemke, R.W.; Cuneo, M.E.; Mehlhorn, T.A.
1996-01-01
A theory of radial beam uniformity in extraction ion diodes is presented. The theory is based on a locally one-dimensional analysis of the diamagnetic compression of magnetic streamlines and the self-consistent determination of the virtual cathode location. The radial dependence of the applied magnetic field is used to determine the critical parameters of this locally one-dimensional treatment. The theory has been incorporated into the ATHETA magnetic field code to allow the rapid evaluation of realistic magnetic field configurations. Comparisons between the theoretical results, simulations with the QUICKSILVER code, and experiments on the PBFA-X accelerator establish the usefulness of this tool for tuning magnetic fields to improve ion beam uniformity. The consequences of poor beam uniformity on the evolution of ion diode instabilities are discussed with supporting evidence from simulations, theory, and experiments. (author). 8 figs., 15 refs
Uniform current density and divergence control in high power extraction ion diodes
International Nuclear Information System (INIS)
Desjarlais, M.P.; Coats, R.S.; Lockner, T.R.; Pointon, T.D.; Johnson, D.J.; Slutz, S.A.; Lemke, R.W.; Cuneo, M.E.; Melhorn, T.A.
1996-01-01
A theory of radial beam uniformity in extraction ion diodes is presented. The theory is based on a locally one dimensional analysis of the diamagnetic compression of magnetic streamlines and the self consistent determination of the virtual cathode location. The radial dependence of the applied magnetic field is used to determine the critical parameters of this locally one dimensional treatment. The theory has been incorporated into the ATHETA magnetic field code to allow the rapid evaluation of realistic magnetic field configurations. Comparisons between the theoretical results, simulations with the QUICKSILVER code, and experiments on the PBFA-X accelerator establish the usefulness of this tool for tuning magnetic fields to improve ion beam uniformity. The consequences of poor beam uniformity on the evolution of ion diode instabilities are discussed with supporting evidence from simulations, theory, and experiments
Effects of non-uniform embedments on earthquake responses of nuclear reactor building
International Nuclear Information System (INIS)
Koyanagi, Y.; Okamoto, S.; Yoshida, K.; Inove, H.
1989-01-01
The nuclear reactor buildings have the portion embedded in soil. In the seismic design of such structures, it is essential to consider the effects of the embedment on the earthquake response. Most studies on these effects, however, assume the uniform embedment, i.e. the depth of the embedment is constant, which is convenient for the design and analysis. The behavior of the earthquake response considering the three-dimensional aspects of non-uniform embedment has not been made clear yet. In this paper, the authors evaluate the effects of the non-uniform embedment in an inclined ground surface on the earthquake response of a nuclear reactor building as illustrated. A typical PWR type reactor building is chosen as an analysis structure model. Four different types of embedment are set up for the comparison study. The three-dimensional analysis is carried out considering the geometry of embedment
Uniform current density and divergence control in high power extraction ion diodes
Energy Technology Data Exchange (ETDEWEB)
Desjarlais, M P; Coats, R S; Lockner, T R; Pointon, T D; Johnson, D J; Slutz, S A; Lemke, R W; Cuneo, M E; Mehlhorn, T A [Sandia Labs., Albuquerque, NM (United States)
1997-12-31
A theory of radial beam uniformity in extraction ion diodes is presented. The theory is based on a locally one-dimensional analysis of the diamagnetic compression of magnetic streamlines and the self-consistent determination of the virtual cathode location. The radial dependence of the applied magnetic field is used to determine the critical parameters of this locally one-dimensional treatment. The theory has been incorporated into the ATHETA magnetic field code to allow the rapid evaluation of realistic magnetic field configurations. Comparisons between the theoretical results, simulations with the QUICKSILVER code, and experiments on the PBFA-X accelerator establish the usefulness of this tool for tuning magnetic fields to improve ion beam uniformity. The consequences of poor beam uniformity on the evolution of ion diode instabilities are discussed with supporting evidence from simulations, theory, and experiments. (author). 8 figs., 15 refs.
Visual properties and memorising scenes: Effects of image-space sparseness and uniformity.
Lukavský, Jiří; Děchtěrenko, Filip
2017-10-01
Previous studies have demonstrated that humans have a remarkable capacity to memorise a large number of scenes. The research on memorability has shown that memory performance can be predicted by the content of an image. We explored how remembering an image is affected by the image properties within the context of the reference set, including the extent to which it is different from its neighbours (image-space sparseness) and if it belongs to the same category as its neighbours (uniformity). We used a reference set of 2,048 scenes (64 categories), evaluated pairwise scene similarity using deep features from a pretrained convolutional neural network (CNN), and calculated the image-space sparseness and uniformity for each image. We ran three memory experiments, varying the memory workload with experiment length and colour/greyscale presentation. We measured the sensitivity and criterion value changes as a function of image-space sparseness and uniformity. Across all three experiments, we found separate effects of 1) sparseness on memory sensitivity, and 2) uniformity on the recognition criterion. People better remembered (and correctly rejected) images that were more separated from others. People tended to make more false alarms and fewer miss errors in images from categorically uniform portions of the image-space. We propose that both image-space properties affect human decisions when recognising images. Additionally, we found that colour presentation did not yield better memory performance over grayscale images.
Uniform-related infection control practices of dental students
Directory of Open Access Journals (Sweden)
Aljohani Y
2017-04-01
Full Text Available Yazan Aljohani,1 Mohammed Almutadares,1 Khalid Alfaifi,1 Mona El Madhoun,1 Maysoon H Albahiti,2 Nadia Al-Hazmi3 1Internship Program, Faculty of dentistry, King Abdulaziz University, 2Department of Endodontics, King Abdulaziz University, 3Department of Oral Biology, King Abdulaziz University, Faculty of Dentistry, Jeddah, Saudi Arabia Background: Uniform-related infection control practices are sometimes overlooked and underemphasized. In Saudi Arabia, personal protective equipment must meet global standards for infection control, but the country’s Islamic legislature also needs to be taken into account. Aim: To assess uniform-related infection control practices of a group of dental students in a dental school in Saudi Arabia and compare the results with existing literature related to cross-contamination through uniforms in the dental field. Method: A questionnaire was formulated and distributed to dental students at King Abdulaziz University Faculty of Dentistry in Jeddah, Saudi Arabia, which queried the students about their uniform-related infection control practices and their methods and frequency of laundering and sanitizing their uniforms, footwear, and name tags. Results: There is a significant difference between genders with regard to daily uniform habits. The frequency of uniform washing was below the standard and almost 30% of students were not aware of how their uniforms are washed. Added to this, there is no consensus on a unified uniform for male and female students. Conclusion: Information on preventing cross-contamination through wearing uniforms must be supplied, reinforced, and emphasized while taking into consideration the cultural needs of the Saudi society. Keywords: cross-contamination, infection control, dental students, uniforms
Uniform and Non-Uniform Optimum Scalar Quantizers Performances: A Comparative Study
Directory of Open Access Journals (Sweden)
Fendy Santoso
2008-05-01
Full Text Available The aim of this research is to investigate source coding, the representation of information source output by finite R bits/symbol. The performance of optimum quantisers subject to an entropy constraint has been studied. The definitive work in this area is best summarised by Shannon’s source coding theorem, that is, a source with entropy H can be encoded with arbitrarily small error probability at any rate R (bits/source output as long as R>H. Conversely, If R the error probability will be driven away from zero, independent of the complexity of the encoder and the decoder employed. In this context, the main objective of engineers is however to design the optimum code. Unfortunately, the rate-distortion theorem does not provide the recipe for such a design. The theorem does, however, provide the theoretical limit so that we know how close we are to the optimum. The full understanding of the theorem also helps in setting the direction to achieve such an optimum. In this research, we have investigated the performances of two practical scalar quantisers, i.e., a Lloyd-Max quantiser and the uniformly defined one and also a well-known entropy coding scheme, i.e., Huffman coding against their theoretically attainable optimum performance due to Shannon’s limit R. It has been shown that our uniformly defined quantiser could demonstrate superior performance. The performance improvements, in fact, are more noticeable at higher bit rates.
7 CFR 51.1447 - Fairly uniform in color.
2010-01-01
... 7 Agriculture 2 2010-01-01 2010-01-01 false Fairly uniform in color. 51.1447 Section 51.1447... color. Fairly uniform in color means that 90 percent or more of the kernels in the lot have skin color within the range of one or two color classifications. ...
7 CFR 51.1407 - Fairly uniform in color.
2010-01-01
... 7 Agriculture 2 2010-01-01 2010-01-01 false Fairly uniform in color. 51.1407 Section 51.1407 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards... in color. Fairly uniform in color means that the shells do not show sufficient variation in color to...
7 CFR 51.2085 - Fairly uniform color.
2010-01-01
... 7 Agriculture 2 2010-01-01 2010-01-01 false Fairly uniform color. 51.2085 Section 51.2085 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards... color. Fairly uniform color means that the shells do not show excessive variation in color, whether...
78 FR 66655 - Consumer Information; Uniform Tire Quality Grading Standards
2013-11-06
... information indicating the relative performance of passenger car tires in the areas of treadwear, traction... [Docket No. NHTSA-2013-0120] RIN 2127-AL49 Consumer Information; Uniform Tire Quality Grading Standards...). ACTION: Interim final rule; request for comments. SUMMARY: The Uniform Tire Quality Grading Standards...
22 CFR 214.42 - Uniform pay guidelines.
2010-04-01
... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Uniform pay guidelines. 214.42 Section 214.42... Advisory Committees § 214.42 Uniform pay guidelines. (a) A.I.D. follows OMB/CSC guidelines in section 11 of... experts, their compensation shall be fixed in accordance with CSC guidelines and regulations, and the...
50 CFR 510.9 - Uniform pay guidelines.
2010-10-01
... 50 Wildlife and Fisheries 7 2010-10-01 2010-10-01 false Uniform pay guidelines. 510.9 Section 510... ACT § 510.9 Uniform pay guidelines. (a) Compensation of members and staff of, and consultants to the... accordance with guidelines established by the Director of the Office of Management and Budget pursuant to...
44 CFR 12.18 - Uniform pay guidelines.
2010-10-01
... 44 Emergency Management and Assistance 1 2010-10-01 2010-10-01 false Uniform pay guidelines. 12.18 Section 12.18 Emergency Management and Assistance FEDERAL EMERGENCY MANAGEMENT AGENCY, DEPARTMENT OF HOMELAND SECURITY GENERAL ADVISORY COMMITTEES § 12.18 Uniform pay guidelines. (a) Members. Subject to the...
Uniform irradiation of irregularly shaped cavities for photodynamic therapy
Rem, A. I.; van Gemert, M. J.; van der Meulen, F. W.; Gijsbers, G. H.; Beek, J. F.
1997-01-01
It is difficult to achieve a uniform light distribution in irregularly shaped cavities. We have conducted a study on the use of hollow 'integrating' moulds for more uniform light delivery of photodynamic therapy in irregularly shaped cavities such as the oral cavity. Simple geometries such as a
The FEL-TNO uniform open systems model
Luiijf, H.A.M.; Overbeek, P.L.
1989-01-01
The FEL-TNO Uniform Open Systems Model is based upon the IS0/0SI Basic Reference Model and integrates operating systems, (OSI) networks, equipment and media into one single uniform nodel. Usage of the model stimulates the development of operating systen and network independent applications and puts
Conditionally-uniform Feasible Grid Search Algorithm
DEFF Research Database (Denmark)
Dziubinski, Matt P.
We present and evaluate a numerical optimization method (together with an algorithm for choosing the starting values) pertinent to the constrained optimization problem arising in the estimation of the GARCH models with inequality constraints, in particular the Simplied Component GARCH Model...... (SCGARCH), together with algorithms for the objective function and analytical gradient computation for SCGARCH....
Design and validation of a uniform flow microreactor
Energy Technology Data Exchange (ETDEWEB)
Yi, Seung Jae; Kim, Kyung Chun; Chang, Seung Cheol [Pusan National University, Busan (Korea, Republic of); Park, Ji Min [Global HQ, Hankook Tire Co., Daejeon (Korea, Republic of)
2014-01-15
We present a design method to characterize uniform flows in a microreactor for high performance surface plasmon resonance (SPR) a general-purpose biosensor chips. The shape of the microreactor is designed based on an approximate pressure drop model. The number of micro-pillars and the slopes of the inlet and outlet linear chambers are two dominant parameters used to minimize the velocity difference in the microreactor. The flow uniformity was examined quantitatively by numerical and experimental visualization methods. A computational fluid dynamics (CFD) analysis demonstrates that the designed microreactor has a fairly uniform velocity profile in the reaction zone for a wide range of flow rates. The velocity field in the fabricated microreactor was measured using the micro-particle image velocimetry (μ-PIV) method, and the flow uniformity was confirmed experimentally. The performance of the uniform flow microreactor was verified using the fluorescence antibody technique.
Weak completeness of the Bourbaki quasi-uniformity
Directory of Open Access Journals (Sweden)
M.A. Sánchez Granero
2001-04-01
Full Text Available The concept of semicompleteness (weaker than half-completeness is defined for the Bourbaki quasi-uniformity of the hyperspace of a quasi-uniform space. It is proved that the Bourbaki quasi-uniformity is semicomplete in the space of nonempty sets of a quasi-uniform space (X,U if and only if each stable filter on (X,U* has a cluster point in (X,U. As a consequence the space of nonempty sets of a quasi-pseudometric space is semicomplete if and only if the space itself is half-complete. It is also given a characterization of semicompleteness of the space of nonempty U*-compact sets of a quasi-uniform space (X,U which extends the well known Zenor-Morita theorem.
Aspects of microwave-heating uniformity
International Nuclear Information System (INIS)
Ginsberg, T.; Makowitz, H.
1983-01-01
Interest has been shown in the field of nuclear reactor safety in the use of microwave heating to simulate the nuclear heat source. The objective of the investigation reported here was to evaluate the usefulness of microwave dielectric heating as a simulator of the nuclear heat source in experiments which simulate the process of boiling of molten mixtures of nuclear fuel and steel. This paper summarizes the results of studies of several aspects of energy deposition in dielectric liquid samples which are exposed to microwave radiation
ELECTRONIC CIRCUIT BOARDS NON-UNIFORM COOLING SYSTEM MODEL
Directory of Open Access Journals (Sweden)
D. V. Yevdulov
2016-01-01
Full Text Available Abstract. The paper considers a mathematical model of non-uniform cooling of electronic circuit boards. The block diagram of the system implementing this approach, the method of calculation of the electronic board temperature field, as well as the principle of its thermal performance optimizing are presented. In the considered scheme the main heat elimination from electronic board is produced by the radiator system, and additional cooling of the most temperature-sensitive components is produced by thermoelectric batteries. Are given the two-dimensional temperature fields of the electronic board during its uniform and non-uniform cooling, is carried out their comparison. As follows from the calculations results, when using a uniform overall cooling of electronic unit there is a waste of energy for the cooling 0f electronic board parts which temperature is within acceptable temperature range without the cooling system. This approach leads to the increase in the cooling capacity of used thermoelectric batteries in comparison with the desired values. This largely reduces the efficiency of heat elimination system. The use for electronic boards cooling of non-uniform local heat elimination removes this disadvantage. The obtained dependences show that in this case, the energy required to create a given temperature is smaller than when using a common uniform cooling. In this approach the temperature field of the electronic board is more uniform and the cooling is more efficient.
Green Design and Sustainable Development of School Uniforms
Cui, Yumei; Fang, Xuemeng; Zhou, Honglei
2018-01-01
Since the 1990s, the school uniform has gradually become an integral part of campus culture construction. A school uniform is not only an iconic symbol of students and a school, but also the carrier of campus culture, with special education function and cultural connotation. However in the same time, many problems exist in the design, making and material selection of school uniforms, in which, substandard fabric quality is the most serious problem. To ensure the quality, health and safety of school uniforms, in my opinion, priority should be given to green design and sustainable development in the design process of school uniforms, which will be more conducive to promoting the sound development of school uniforms. In today’s economic development, the globalization of mass production is no longer just a symbol of challenging the limits of human beings, but to explore the unlimited potential of human spiritual collaboration. If we want to have a better future on this planet, we need to completely redefine the key issue we need to address, that is, green design. The rise of green products is a great progress of human understanding and solving environmental problems. It is the inevitable development trend of commodity production, and will have a profound impact on human survival and development in the future. School uniform is an important part of campus culture construction. In order to not damage the health of primary and secondary school students, in the school uniform design and production process should follow the concept of “green design” to achieve the school uniform style, color, material design, a comprehensive “green” positioning.
Non-uniformity Correction of Infrared Images by Midway Equalization
Directory of Open Access Journals (Sweden)
Yohann Tendero
2012-07-01
Full Text Available The non-uniformity is a time-dependent noise caused by the lack of sensor equalization. We present here the detailed algorithm and on line demo of the non-uniformity correction method by midway infrared equalization. This method was designed to suit infrared images. Nevertheless, it can be applied to images produced for example by scanners, or by push-broom satellites. The obtained single image method works on static images, is fully automatic, having no user parameter, and requires no registration. It needs no camera motion compensation, no closed aperture sensor equalization and is able to correct for a fully non-linear non-uniformity.
Wientjes, J.G.M.; Soede, N.M.; Laurenssen, B.F.A.; Koopmanschap, R.E.; Brand, van den H.; Kemp, B.
2013-01-01
Piglet birth weight and litter uniformity are important for piglet survival. Insulin-stimulating sow diets before mating may improve subsequent piglet birth weights and litter uniformity, but the physiological mechanisms involved are not clear. This study evaluated effects of different levels of
Toward uniform probabilistic seismic hazard assessments for Southeast Asia
Chan, C. H.; Wang, Y.; Shi, X.; Ornthammarath, T.; Warnitchai, P.; Kosuwan, S.; Thant, M.; Nguyen, P. H.; Nguyen, L. M.; Solidum, R., Jr.; Irsyam, M.; Hidayati, S.; Sieh, K.
2017-12-01
Although most Southeast Asian countries have seismic hazard maps, various methodologies and quality result in appreciable mismatches at national boundaries. We aim to conduct a uniform assessment across the region by through standardized earthquake and fault databases, ground-shaking scenarios, and regional hazard maps. Our earthquake database contains earthquake parameters obtained from global and national seismic networks, harmonized by removal of duplicate events and the use of moment magnitude. Our active-fault database includes fault parameters from previous studies and from the databases implemented for national seismic hazard maps. Another crucial input for seismic hazard assessment is proper evaluation of ground-shaking attenuation. Since few ground-motion prediction equations (GMPEs) have used local observations from this region, we evaluated attenuation by comparison of instrumental observations and felt intensities for recent earthquakes with predicted ground shaking from published GMPEs. We then utilize the best-fitting GMPEs and site conditions into our seismic hazard assessments. Based on the database and proper GMPEs, we have constructed regional probabilistic seismic hazard maps. The assessment shows highest seismic hazard levels near those faults with high slip rates, including the Sagaing Fault in central Myanmar, the Sumatran Fault in Sumatra, the Palu-Koro, Matano and Lawanopo Faults in Sulawesi, and the Philippine Fault across several islands of the Philippines. In addition, our assessment demonstrates the important fact that regions with low earthquake probability may well have a higher aggregate probability of future earthquakes, since they encompass much larger areas than the areas of high probability. The significant irony then is that in areas of low to moderate probability, where building codes are usually to provide less seismic resilience, seismic risk is likely to be greater. Infrastructural damage in East Malaysia during the 2015
A survey on locally uniformly A-convex algebras
International Nuclear Information System (INIS)
Oudadess, M.
1984-12-01
Using a bornological technic of M. Akkar, we reduce the study of classical questions (spectrum, boundedness of characters, functional calculus, etc.) in locally uniformly A-convex algebras to the Banach case. (author)
UOBPRM: A uniformly distributed obstacle-based PRM
Yeh, Hsin-Yi; Thomas, Shawna; Eppstein, David; Amato, Nancy M.
2012-01-01
This paper presents a new sampling method for motion planning that can generate configurations more uniformly distributed on C-obstacle surfaces than prior approaches. Here, roadmap nodes are generated from the intersections between C
Uniform irradiation system using beam scanning method for cyclotron
International Nuclear Information System (INIS)
Agematsu, Takashi; Okumura, Susumu; Arakawa, Kazuo
1994-03-01
JAERI AVF-cyclotron is equipped with an ion beam scanner for large area irradiation. The two-dimensional fluence distribution of ion beam obtained using cellulose triacetate film dosimeter was not uniform. This is resulted from the distortion of excitation current for electromagnet of the scanner. So, the beam scanning condition, i.e., the relation between the ion species, the beam profile and the scanning width, was extremely limited to make a good uniformity. We have developed a beam scanning simulator to get fluence distributions by calculation and then compared the simulated distributions with the measured ones. It was revealed that the both of them are in good agreement and the beam scanning condition to get good uniformity was led by using this simulator. On the basis of these results, the power supply of scanner was improved. A good uniformity of beam distribution was available. (author)
Highly uniform parallel microfabrication using a large numerical aperture system
Energy Technology Data Exchange (ETDEWEB)
Zhang, Zi-Yu; Su, Ya-Hui, E-mail: ustcsyh@ahu.edu.cn, E-mail: dongwu@ustc.edu.cn [School of Electrical Engineering and Automation, Anhui University, Hefei 230601 (China); Zhang, Chen-Chu; Hu, Yan-Lei; Wang, Chao-Wei; Li, Jia-Wen; Chu, Jia-Ru; Wu, Dong, E-mail: ustcsyh@ahu.edu.cn, E-mail: dongwu@ustc.edu.cn [CAS Key Laboratory of Mechanical Behavior and Design of Materials, Department of Precision Machinery and Precision Instrumentation, University of Science and Technology of China, Hefei 230026 (China)
2016-07-11
In this letter, we report an improved algorithm to produce accurate phase patterns for generating highly uniform diffraction-limited multifocal arrays in a large numerical aperture objective system. It is shown that based on the original diffraction integral, the uniformity of the diffraction-limited focal arrays can be improved from ∼75% to >97%, owing to the critical consideration of the aperture function and apodization effect associated with a large numerical aperture objective. The experimental results, e.g., 3 × 3 arrays of square and triangle, seven microlens arrays with high uniformity, further verify the advantage of the improved algorithm. This algorithm enables the laser parallel processing technology to realize uniform microstructures and functional devices in the microfabrication system with a large numerical aperture objective.
22 CFR 1203.735-212 - Wearing of uniforms.
2010-04-01
... RESPONSIBILITIES AND CONDUCT Ethical and Other Conduct and Responsibilities of Employees § 1203.735-212 Wearing of....2b prohibits the purchase from Agency funds of uniforms or any item of personal wearing apparel other...
An explicit local uniform large deviation bound for Brownian bridges
Wittich, O.
2005-01-01
By comparing curve length in a manifold and a standard sphere, we prove a local uniform bound for the exponent in the Large Deviation formula that describes the concentration of Brownian bridges to geodesics.
Linking of uniform random polygons in confined spaces
Arsuaga, J.; Blackstone, T.; Diao, Y.; Karadayi, E.; Saito, M.
2007-03-01
In this paper, we study the topological entanglement of uniform random polygons in a confined space. We derive the formula for the mean squared linking number of such polygons. For a fixed simple closed curve in the confined space, we rigorously show that the linking probability between this curve and a uniform random polygon of n vertices is at least 1-O\\big(\\frac{1}{\\sqrt{n}}\\big) . Our numerical study also indicates that the linking probability between two uniform random polygons (in a confined space), of m and n vertices respectively, is bounded below by 1-O\\big(\\frac{1}{\\sqrt{mn}}\\big) . In particular, the linking probability between two uniform random polygons, both of n vertices, is bounded below by 1-O\\big(\\frac{1}{n}\\big) .
Linking of uniform random polygons in confined spaces
International Nuclear Information System (INIS)
Arsuaga, J; Blackstone, T; Diao, Y; Karadayi, E; Saito, M
2007-01-01
In this paper, we study the topological entanglement of uniform random polygons in a confined space. We derive the formula for the mean squared linking number of such polygons. For a fixed simple closed curve in the confined space, we rigorously show that the linking probability between this curve and a uniform random polygon of n vertices is at least 1-O(1/√n). Our numerical study also indicates that the linking probability between two uniform random polygons (in a confined space), of m and n vertices respectively, is bounded below by 1-O(1/√(mn)). In particular, the linking probability between two uniform random polygons, both of n vertices, is bounded below by 1-O(1/n)
Non-uniform sampling of NMR relaxation data
DEFF Research Database (Denmark)
Schwarz-Linnet, Troels; Teilum, Kaare
2016-01-01
The use of non-uniform sampling of NMR spectra may give significant reductions in the data acquisition time. For quantitative experiments such as the measurement of spin relaxation rates, non-uniform sampling is however not widely used as inaccuracies in peak intensities may lead to errors...... in the extracted dynamic parameters. By systematic reducing the coverage of the Nyquist grid of (15)N Carr-Purcell-Meiboom-Gill (CPMG) relaxation dispersion datasets for four different proteins and performing a full data analysis of the resulting non-uniform sampled datasets, we have compared the performance...... of the multi-dimensional decomposition and iterative re-weighted least-squares algorithms in reconstructing spectra with accurate peak intensities. As long as a single fully sampled spectrum is included in a series of otherwise non-uniform sampled two-dimensional spectra, multi-dimensional decomposition...
UOBPRM: A uniformly distributed obstacle-based PRM
Yeh, Hsin-Yi
2012-10-01
This paper presents a new sampling method for motion planning that can generate configurations more uniformly distributed on C-obstacle surfaces than prior approaches. Here, roadmap nodes are generated from the intersections between C-obstacles and a set of uniformly distributed fixed-length segments in C-space. The results show that this new sampling method yields samples that are more uniformly distributed than previous obstacle-based methods such as OBPRM, Gaussian sampling, and Bridge test sampling. UOBPRM is shown to have nodes more uniformly distributed near C-obstacle surfaces and also requires the fewest nodes and edges to solve challenging motion planning problems with varying narrow passages. © 2012 IEEE.
Uniformity across 200 mm silicon wafers printed by nanoimprint lithography
International Nuclear Information System (INIS)
Gourgon, C; Perret, C; Tallal, J; Lazzarino, F; Landis, S; Joubert, O; Pelzer, R
2005-01-01
Uniformity of the printing process is one of the key parameters of nanoimprint lithography. This technique has to be extended to large size wafers to be useful for several industrial applications, and the uniformity of micro and nanostructures has to be guaranteed on large surfaces. This paper presents results of printing on 200 mm diameter wafers. The residual thickness uniformity after printing is demonstrated at the wafer scale in large patterns (100 μm), in smaller lines of 250 nm and in sub-100 nm features. We show that a mould deformation occurs during the printing process, and that this deformation is needed to guarantee printing uniformity. However, the mould deformation is also responsible for the potential degradation of the patterns
Synthesis of bulk quantity BN nanotubes with uniform morphology
International Nuclear Information System (INIS)
Wen, G.; Zhang, T.; Huang, X.X.; Zhong, B.; Zhang, X.D.; Yu, H.M.
2010-01-01
Bulk quantity hexagonal BN nanotubes (h-BNNTs) with uniform morphology were synthesized via an improved ball-milling and annealing method. The sample was characterized by X-ray photoelectron spectrometry, electron energy loss spectroscopy, X-ray diffraction, scanning electron microscopy, conventional transmission electron microscopy (TEM) and high-resolution TEM. The results show that the fabricated BNNTs have a uniform diameter ranging from 80 to 100 nm and a length of about 50-60 μm.
Effects of Potential Lane-Changing Probability on Uniform Flow
International Nuclear Information System (INIS)
Tang Tieqiao; Huang Haijun; Shang Huayan
2010-01-01
In this paper, we use the car-following model with the anticipation effect of the potential lane-changing probability (Acta Mech. Sin. 24 (2008) 399) to investigate the effects of the potential lane-changing probability on uniform flow. The analytical and numerical results show that the potential lane-changing probability can enhance the speed and flow of uniform flow and that their increments are related to the density.
Fiber optic based optical tomography sensor for monitoring plasma uniformity
International Nuclear Information System (INIS)
Benck, Eric C.; Etemadi, Kasra
2001-01-01
A new type of fiber optic based optical tomography sensor has been developed for in situ monitoring of plasma uniformity. Optical tomography inverts optical emission measurements into the actual plasma distribution without assuming radial symmetry. The new sensor is designed to operate with only two small windows and acquire the necessary data in less than a second. Optical tomography is being tested on an ICP-GEC RF plasma source. Variations in plasma uniformity are measured as a function of different plasma conditions
Uniform risk functionals for characterization of strong earthquake ground motions
International Nuclear Information System (INIS)
Anderson, J.G.; Trifunac, M.D.
1978-01-01
A uniform risk functional (e.g., Fourier spectrum, response spectrum, duration, etc.) is defined so that the probability that it is exceeded by some earthquake during a selected period of time is independent of the frequency of seismic waves. Such a functional is derived by an independent calculation, at each frequency, for the probability that the quantity being considered will be exceeded. Different aspects of the seismicity can control the amplitude of a uniform risk functional in different frequency ranges, and a uniform risk functional does not necessarily describe the strong shaking from any single earthquake. To be useful for calculating uniform risk functionals, a scaling relationship must provide an independent estimate of amplitudes of the functional in several frequency bands. The scaling relationship of Trifunac (1976) for Fourier spectra satisfies this requirement and further describes the distribution of spectral amplitudes about the mean trend; here, it is applied to find uniform risk Fourier amplitude spectra. In an application to finding the uniform risk spectra at a realistic site, this method is quite sensitive to the description of seismicity. Distinct models of seismicity, all consistent with our current level of knowledge of an area, can give significantly different risk estimates
Vertical uniformity of cells and nuclei in epithelial monolayers.
Neelam, Srujana; Hayes, Peter Robert; Zhang, Qiao; Dickinson, Richard B; Lele, Tanmay P
2016-01-22
Morphological variability in cytoskeletal organization, organelle position and cell boundaries is a common feature of cultured cells. Remarkable uniformity and reproducibility in structure can be accomplished by providing cells with defined geometric cues. Cells in tissues can also self-organize in the absence of directing extracellular cues; however the mechanical principles for such self-organization are not understood. We report that unlike horizontal shapes, the vertical shapes of the cell and nucleus in the z-dimension are uniform in cells in cultured monolayers compared to isolated cells. Apical surfaces of cells and their nuclei in monolayers were flat and heights were uniform. In contrast, isolated cells, or cells with disrupted cell-cell adhesions had nuclei with curved apical surfaces and variable heights. Isolated cells cultured within micron-sized square wells displayed flat cell and nuclear shapes similar to cells in monolayers. Local disruption of nuclear-cytoskeletal linkages resulted in spatial variation in vertical uniformity. These results suggest that competition between cell-cell pulling forces that expand and shorten the vertical cell cross-section, thereby widening and flattening the nucleus, and the resistance of the nucleus to further flattening results in uniform cell and nuclear cross-sections. Our results reveal the mechanical principles of self-organized vertical uniformity in cell monolayers.
An Assessment of the Uniform Funding Policy of DoD Directive 3200.11.
1980-09-01
34 Unpublished master’s thesis. GSM/SM/73-10, AFIT/EN, Wright-Patterson AFB OH 45433, 7 January 1974. Horngren , Charles T. Cost Accounting : A Management...reverse side if noceeeary aid identify by block number) Uniform Funding Policy Test Facilities Test and Evaluation Cost Accounting Accounting 20...segregated from overhead as a cost accounting device in both Government and industry. Historically, this distinc- tion has merely aided distribution of total
Energy Technology Data Exchange (ETDEWEB)
Zupančič, Matevž, E-mail: matevz.zupancic@fs.uni-lj.si; Može, Matic; Gregorčič, Peter; Golobič, Iztok
2017-03-31
Highlights: • Surfaces with periodically changed wettability were produced by a ns marking laser. • Heat transfer was investigated on uniformly and non-uniformly wettable surfaces. • Microporous surfaces with non-uniform wettability enhance boiling heat transfer. • The most bubble nucleations were observed in the vicinity of the microcavities. • Results agree with the predictions of the nucleation criteria. - Abstract: Microstructured uniformly and non-uniformly wettable surfaces were created on 25-μm-thin stainless steel foils by laser texturing using a marking nanosecond Nd:YAG laser (λ = 1064 nm) and utilizing various laser fluences and scan line separations. High-speed photography and high-speed IR thermography were used to investigate nucleate boiling heat transfer on the microstructured surfaces. The most pronounced results were obtained on a surface with non-uniform microstructure and non-uniform wettability. The obtained results show up to a 110% higher heat transfer coefficients and 20–40 times higher nucleation site densities compared to the untextured surface. We show that the number of active nucleation sites is significantly increased in the vicinity of microcavities that appeared in areas with the smallest (10 μm) scan line separation. Furthermore, this confirms the predictions of nucleation criteria and proves that straightforward, cost-effective nanosecond laser texturing allows the production of cavities with diameters of up to a few micrometers and surfaces with non-uniform wettability. Additionally, this opens up important possibilities for a more deterministic control over the complex boiling process.
International Nuclear Information System (INIS)
Barnett, P.G.
1964-11-01
The practice of using burnout data for uniformly heated round tubes to predict burnout in non-uniformly heated reactor channels having complex cross sections is examined. At least two hypotheses are involved: (i) a relationship exists between uniform and non-uniform heat flux distributions and (ii) a relationship exists between simple and complex channel cross sections. Use of two such hypotheses each accurate to ± 15% and a correlation of uniformly heated round tube data having an R.M.S. error of 5%, could yield errors of ± 40% in any predicted value; this figure of ± 40% is regarded as a realistic upper limit for design purposes. It is shown that no method can exist for relating different channel cross sections to within ± 15% and existing methods for relating different heat flux distributions incur some errors exceeding 20%. Furthermore, any suggested method for relating different heat flux distributions can be adequately checked only when a sufficiently large number of results are available and then the preferable alternative of correlating the data is possible. It is concluded that no reliable method can exist for predicting burnout in rod bundles from uniformly heated round tube data with sufficient accuracy for design purposes. (author)
Institute of Scientific and Technical Information of China (English)
石东亮; 陈运能; 邝湘宁
2017-01-01
使用不同比例单色棉纤维和本色棉纤维经混纺、织造后得到色纺针织面料样品,用测色软件对样品上选定的区域进行成像,然后微分成大量单元进行测色.经分析发现,色纺针织物的色彩均匀度,可以用各测色单元相对于标准色色差ΔEi的CV值来表征,该CV值和人工目测得到的色彩均匀度等级存在高度的相关性.当CV值大于2.0%时,样品的色彩均匀度较差,存在显著的色彩分布不均匀;当CV值小于1.0%时,样品的色彩均匀度较好,外观上仅有轻微差异或无法觉察.%In this paper, of single-colour cotton fibre with different ratio is blended with grey cotton fibre, then spun and knitted to gain fibre-dyed knitted fabric samples.The colour testing software was used to image the chosen zone on the sample.Then, the zone is differentiated into a large number of units for colour testing.The analysis shows that the colour uniformity of these fabrics can be characterized by CV value of colour difference ΔEi of each colour testing unit relative to standard colour.The CV value is highly related to colour uniformity grade gained by manual visual inspection.Furthermore, when CV value is higher than 2.0%, colour uniformity of samples is bad, and significant colour distribution unevenness exists.When CV value is less than 1.0%, colour uniformity of samples is good, and there is only slight difference or invisible difference on the appearance.
A novel scene-based non-uniformity correction method for SWIR push-broom hyperspectral sensors
Hu, Bin-Lin; Hao, Shi-Jing; Sun, De-Xin; Liu, Yin-Nian
2017-09-01
A novel scene-based non-uniformity correction (NUC) method for short-wavelength infrared (SWIR) push-broom hyperspectral sensors is proposed and evaluated. This method relies on the assumption that for each band there will be ground objects with similar reflectance to form uniform regions when a sufficient number of scanning lines are acquired. The uniform regions are extracted automatically through a sorting algorithm, and are used to compute the corresponding NUC coefficients. SWIR hyperspectral data from airborne experiment are used to verify and evaluate the proposed method, and results show that stripes in the scenes have been well corrected without any significant information loss, and the non-uniformity is less than 0.5%. In addition, the proposed method is compared to two other regular methods, and they are evaluated based on their adaptability to the various scenes, non-uniformity, roughness and spectral fidelity. It turns out that the proposed method shows strong adaptability, high accuracy and efficiency.
Directory of Open Access Journals (Sweden)
Youwei He
2018-02-01
Full Text Available Although technical advances in hydraulically fracturing and drilling enable commercial production from tight reservoirs, oil/gas recovery remains at a low level. Due to the technical and economic limitations of well-testing operations in tight reservoirs, rate-transient analysis (RTA has become a more attractive option. However, current RTA models hardly consider the effect of the non-uniform production on rate decline behaviors. In fact, PLT results demonstrate that production profile is non-uniform. To fill this gap, this paper presents an improved RTA model of multi-fractured horizontal wells (MFHWs to investigate the effects of non-uniform properties of hydraulic fractures (production of fractures, fracture half-length, number of fractures, fracture conductivity, and vertical permeability on rate transient behaviors through the diagnostic type curves. Results indicate obvious differences on the rate decline curves among the type curves of uniform properties of fractures (UPF and non-uniform properties of fractures (NPF. The use of dimensionless production integral derivative curve magnifies the differences so that we can diagnose the phenomenon of non-uniform production. Therefore, it’s significant to incorporate the effects of NPF into the RDA models of MFHWs, and the model proposed in this paper enables us to better evaluate well performance based on long-term production data.
Washing and changing uniforms: is guidance being adhered to?
Potter, Yvonne Camilla; Justham, David
To allay public apprehension regarding the risk of nurses' uniforms transmitting healthcare-associated infections (HCAI), national and local guidelines have been issued to control use, laundry and storage. This paper aims to measure the knowledge of registered nurses (RNs) and healthcare assistants (HCAs) working within a rural NHS foundation Trust and their adherence to the local infection prevention and control (IPC) standard regarding uniforms through a Trust-wide audit. Stratified random sampling selected 597 nursing staff and 399 responded (67%) by completing a short questionnaire based on the local standard. Responses were coded and transferred to SPSS (v. 17) for analysis. The audit found that nursing staff generally adhere to the guidelines, changing their uniforms daily and immediately upon accidental soiling, and wearing plastic aprons where indicated. At home, staff normally machine-wash and then iron their uniforms at the hottest setting. Nevertheless, few observe the local direction to place their newly-laundered uniforms in protective covers. This paper recommends a re-audit to compare compliance rates with baseline figures and further research into the reasons why compliance is lacking to sanction interventions for improvement, such as providing relevant staff education and re-introducing appropriate changing facilities.
Leader propagation in uniform background fields in SF6
International Nuclear Information System (INIS)
Seeger, M; Niemeyer, L; Bujotzek, M
2009-01-01
The breakdown mechanism of compressed SF 6 in gas insulation is known to be controlled by stepped leader propagation. This process is still not well understood in uniform and weakly non-uniform background fields with small electrode protrusions, such as particles or surface roughness. In a previous publication an investigation of partial discharges and breakdown in uniform background fields that focused on streamer and leader inception mechanisms was presented (Seeger et al 2008 J. Phys. D: Appl. Phys. 41 185204). In this paper we present for the first time a physical leader propagation model that consistently describes the observed phenomena in uniform background fields in SF 6 . The model explains two different types of leader breakdown; these can be associated with the precursor and the stem mechanisms. It also yields the parameters of stepped leader propagation, which include step lengths, associated step charges, step times and fields and temperatures in the leader channel. Further, it explains the features of arrested leaders in uniform background fields. The model predicts the range of parameters under which arrested and breakdown leaders occur in good agreement with the experimental data.
Uniform design based SVM model selection for face recognition
Li, Weihong; Liu, Lijuan; Gong, Weiguo
2010-02-01
Support vector machine (SVM) has been proved to be a powerful tool for face recognition. The generalization capacity of SVM depends on the model with optimal hyperparameters. The computational cost of SVM model selection results in application difficulty in face recognition. In order to overcome the shortcoming, we utilize the advantage of uniform design--space filling designs and uniformly scattering theory to seek for optimal SVM hyperparameters. Then we propose a face recognition scheme based on SVM with optimal model which obtained by replacing the grid and gradient-based method with uniform design. The experimental results on Yale and PIE face databases show that the proposed method significantly improves the efficiency of SVM model selection.
Analytical inversion formula for uniformly attenuated fan-beam projections
International Nuclear Information System (INIS)
Weng, Y.; Zeng, G.L.; Gullberg, G.T.
1997-01-01
In deriving algorithms to reconstruct single photon emission computed tomography (SPECT) projection data, it is important that the algorithm compensates for photon attenuation in order to obtain quantitative reconstruction results. A convolution backprojection algorithm was derived by Tretiak and Metz to reconstruct two-dimensional (2-D) transaxial slices from uniformly attenuated parallel-beam projections. Using transformation of coordinates, this algorithm can be modified to obtain a formulation useful to reconstruct uniformly attenuated fan-beam projections. Unlike that for parallel-beam projections, this formulation does not produce a filtered backprojection reconstruction algorithm but instead has a formulation that is an inverse integral operator with a spatially varying kernel. This algorithm thus requires more computation time than does the filtered backprojection reconstruction algorithm for the uniformly attenuated parallel-beam case. However, the fan-beam reconstructions demonstrate the same image quality as that of parallel-beam reconstructions
Function spaces with uniform, fine and graph topologies
McCoy, Robert A; Jindal, Varun
2018-01-01
This book presents a comprehensive account of the theory of spaces of continuous functions under uniform, fine and graph topologies. Besides giving full details of known results, an attempt is made to give generalizations wherever possible, enriching the existing literature. The goal of this monograph is to provide an extensive study of the uniform, fine and graph topologies on the space C(X,Y) of all continuous functions from a Tychonoff space X to a metric space (Y,d); and the uniform and fine topologies on the space H(X) of all self-homeomorphisms on a metric space (X,d). The subject matter of this monograph is significant from the theoretical viewpoint, but also has applications in areas such as analysis, approximation theory and differential topology. Written in an accessible style, this book will be of interest to researchers as well as graduate students in this vibrant research area.
Dynamics beyond uniform hyperbolicity a global geometric and probabilistic perspective
Bonatti, Christian; Viana, Marcelo
2005-01-01
The notion of uniform hyperbolicity, introduced by Steve Smale in the early sixties, unified important developments and led to a remarkably successful theory for a large class of systems: uniformly hyperbolic systems often exhibit complicated evolution which, nevertheless, is now rather well understood, both geometrically and statistically.Another revolution has been taking place in the last couple of decades, as one tries to build a global theory for "most" dynamical systems, recovering as much as possible of the conclusions of the uniformly hyperbolic case, in great generality. This book aims to put such recent developments in a unified perspective, and to point out open problems and likely directions for further progress. It is aimed at researchers, both young and senior, willing to get a quick, yet broad, view of this part of dynamics. Main ideas, methods, and results are discussed, at variable degrees of depth, with references to the original works for details and complementary information.
Preparation of uniform porous hydroxyapatite biomaterials by a new method
International Nuclear Information System (INIS)
Tang Yuejun; Tang Yuefeng; Lv Chuntang; Zhou Zhonghua
2008-01-01
In this paper, a new method of preparation of uniform porous hydroxyapatite biomaterials was reported. In order to obtain uniform porous biomaterials, disk samples were formed by the mixture of hydroxyapatite (HAP) powders and monodispersed polystyrene microspheres, and then HAP uniform porous materials with different diameter and different porosity (diameter: 436 ± 25 nm, 892 ± 20 nm and 1890 ± 20 nm, porosity: 46.5%, 41.3% and 34.7%, respectively) were prepared by sintering these disk samples at 1250 deg. C for 5 h. The pure phase of HAP powders fabricated by the hydrothermal technology was confirmed by X-ray diffraction (XRD). The surface and size distribution of pores in HAP biomaterials were observed by scanning electron microscopy (SEM), and the pore size distribution in porous HAP biomaterials was tested by mercury intrusion method
Directory of Open Access Journals (Sweden)
Jie Zhang
2013-01-01
Full Text Available In association rule mining, evaluating an association rule needs to repeatedly scan database to compare the whole database with the antecedent, consequent of a rule and the whole rule. In order to decrease the number of comparisons and time consuming, we present an attribute index strategy. It only needs to scan database once to create the attribute index of each attribute. Then all metrics values to evaluate an association rule do not need to scan database any further, but acquire data only by means of the attribute indices. The paper visualizes association rule mining as a multiobjective problem rather than a single objective one. In order to make the acquired solutions scatter uniformly toward the Pareto frontier in the objective space, elitism policy and uniform design are introduced. The paper presents the algorithm of attribute index and uniform design based multiobjective association rule mining with evolutionary algorithm, abbreviated as IUARMMEA. It does not require the user-specified minimum support and minimum confidence anymore, but uses a simple attribute index. It uses a well-designed real encoding so as to extend its application scope. Experiments performed on several databases demonstrate that the proposed algorithm has excellent performance, and it can significantly reduce the number of comparisons and time consumption.
Zhang, Jie; Wang, Yuping; Feng, Junhong
2013-01-01
In association rule mining, evaluating an association rule needs to repeatedly scan database to compare the whole database with the antecedent, consequent of a rule and the whole rule. In order to decrease the number of comparisons and time consuming, we present an attribute index strategy. It only needs to scan database once to create the attribute index of each attribute. Then all metrics values to evaluate an association rule do not need to scan database any further, but acquire data only by means of the attribute indices. The paper visualizes association rule mining as a multiobjective problem rather than a single objective one. In order to make the acquired solutions scatter uniformly toward the Pareto frontier in the objective space, elitism policy and uniform design are introduced. The paper presents the algorithm of attribute index and uniform design based multiobjective association rule mining with evolutionary algorithm, abbreviated as IUARMMEA. It does not require the user-specified minimum support and minimum confidence anymore, but uses a simple attribute index. It uses a well-designed real encoding so as to extend its application scope. Experiments performed on several databases demonstrate that the proposed algorithm has excellent performance, and it can significantly reduce the number of comparisons and time consumption.
Creation of the uniform Chernobyl register of Russia and Belarus
International Nuclear Information System (INIS)
Sosnouskaya, Alena; Kotava, Aksana; Ivanov, Victor; Maksutov, Marat
2008-01-01
Creation of operation of uniform medical and dosimetric data banks for carrying out of collateral wide-scale radiation epidemiological researches and prediction of medical consequences of Chernobyl accident (ChA) in territory of Russia and Belarus. On the basis of medical and dosimetric data banks of the national registers of Russia and Belarus the uniform technology of collection personal of a state information of health of the population, injured from ChA . Three levels of observation are created. The first level - Bryansk area of Russia and Gomel area of Belarus, interests of research - radiation hazards of oncologic diseases of various localizations for the population living in these territories. The second level - Bryansk, Kaluga, Tula and Oryol area of Russia and Brest, Vitebsk, Gomel, Grodno, Minsk and Mogilyov area of Belarus, preferred direction of researches - thyroid cancer. The third level all territory of Russia and Belarus, area of research - medical consequences for health of the liquidators, their children and persons migrating from polluted territories. Personal uniform sub-registers are created and function on a stationary value to a basis. Is sub-registers containing information about diseases by a thyroid cancer, leukemia and breast cancer, uniform register of the liquidators and their children, uniform cancer-register of the liquidators and uniform cancer-register of the population living in territories with density of contamination on Cs 137 more than 185 kBq/m 2 . The personal information on 20440 cases of thyroid cancer, 5234 cases of a leukemia, 16679 cases of breast cancer, 252884 liquidators, 6882 cases of a cancer of various localizations among the liquidators, 35423 children of the liquidators, 11407 cases of oncologic diseases among the population living in territories with density of contamination on Cs 137 more than 185 kBq/m 2 is accumulated. (author)
A control system for uniform bead in fillet arc welding on tack welds
International Nuclear Information System (INIS)
Kim, Jae Woong; Lee, Jun Young
2008-01-01
Positioning a workpiece accurately and preventing weld distortion, tack welding is often adopted before main welding in the construction of welded structures. However, this tack weld deteriorates the final weld bead profile, so that the grinding process is usually performed for a uniform weld bead profile. In this study, a control system for uniform weld bead is proposed for the fillet arc welding on tack welds. The system consists of GMA welding machine, torch manipulator, laser vision sensor for measuring the tack weld size and the database for optimal welding conditions. Experiments have been performed for constructing the database and for evaluating the control capability of the system. It has been shown that the system has the capability to smooth the bead at the high level of quality
Antibiosis resistance in national uniform wheat yield trials against rhopalosiphum padi (L.)
International Nuclear Information System (INIS)
Akhtar, N.; Ashfaque, M.; Gillani, W.A.; Ata-ul-Mohsin; Tahfeen, A.; Begum, I.
2010-01-01
The germplasm of National Uniform Wheat Yield Trials (Normal) (2003-04) were screened against Rhopalosiphum padi L., bird cherry oat aphid at National Agricultural Research Centre, Islamabad. Twenty National Uniform Wheat Yield Trials (NUWYT) , Normal and 12 (NUWYT) rain fed varieties/ lines were evaluated for seedling bulk test to know the resistant, moderately resistant and susceptible wheat varieties/ lines. These results revealed that varieties Diamond and Margalla-99 and lines V-99022, 99B2278 and 7-03 were partially resistant, two lines V-00125 and SD-66 were susceptible and three varieties and ten lines were moderately resistant in seedling bulk test. For antibiosis studies, 10 varieties/ lines out of 20 were selected to know the effect of host plants on the fecundity of R. padi. Two varieties Wafaq-2007 and Diamond were the least preferred for fecundity and one line VOO125 was highly preferred for fecundity. (author)
Uniformity studies in large area triple-GEM based detectors
Energy Technology Data Exchange (ETDEWEB)
Akl, M. Abi [Science Program, Texas A& M University at Qatar, PO Box 23874, Doha (Qatar); Bouhali, O., E-mail: othmane.bouhali@qatar.tamu.edu [Science Program, Texas A& M University at Qatar, PO Box 23874, Doha (Qatar); Qatar Computing Research Institute, Hamad Bin Khalifa University, PO Box 5825, Doha (Qatar); Castaneda, A.; Maghrbi, Y.; Mohamed, T. [Science Program, Texas A& M University at Qatar, PO Box 23874, Doha (Qatar)
2016-10-01
Gas Electron Multiplier (GEM) based detectors have been used in many applications since their introduction in 1997. Large areas, e.g. exceeding 30×30 cm{sup 2}, of GEM detectors are foreseen in future experiments which puts stringent requirements on the uniformity of response across the detection area. We investigate the effect of small variations of several parameters that could affect the uniformity. Parameters such as the anode pitch, the gas gap, the size and the shape of the holes are investigated. Simulation results are presented and compared to previous experimental data.
A range modulator to produce uniform 38K yield
International Nuclear Information System (INIS)
Eilbert, R.F.; Koehler, A.M.; Sisterson, J.M.
1976-01-01
A range modulator has been designed for use with a monoenergetic proton beam to achieve uniform yield of a nuclear reaction with depth in a tissue equivalent medium. Uniform yield to +- 1.5% over a 10 cm depth for the reaction 40 Ca(p, 2pn) 38 K has been demonstrated using protons of 160 MeV initial energy. The modulator is a rotating stepped absorber made of stacked acrylic plastic sheets. The angular extent of each sheet is determined by a computer program which also calculates the resultant depth of dose curve. Peaks in the dose curve may be reduced with slight effect on the yield curve. (author)
On a Generalisation of Uniform Distribution and its Properties
Directory of Open Access Journals (Sweden)
K. Jayakumar
2016-03-01
Full Text Available Nadarajah et al.(2013 introduced a family life time models using truncated negative binomial distribution and derived some properties of the family of distributions. It is a generalization of Marshall-Olkin family of distributions. In this paper, we introduce Generalized Uniform Distribution (GUD using the approach of Nadarajah et al.(2013. The shape properties of density function and hazard function are discussed. The expression for moments, order statistics, entropies are obtained. Estimation procedure is also discussed.The GDU introduced here is a generalization of the Marshall-Olkin extended uniform distribution studied in Jose and Krishna(2011.
Coating strategy for enhancing illumination uniformity in a lithographic condenser
International Nuclear Information System (INIS)
Gaines, D.P.; Vernon, S.P.; Sommargren, G.E.; Kania, D.R.
1995-01-01
A three-element Koehler condenser system has been fabricated, characterized, and integrated into an EUV lithographic system. The multilayer coatings deposited on the optics were designed to provide optimal radiation transport efficiency and illumination uniformity. Extensive EUV characterization measurements performed on the individual optics and follow-on system measurements indicated that the condenser was operating close to design goals. Multilayer d-spacings were within 0.05 nm of specifications, and reflectances were approximately 60%. Illumination uniformity was better than ±10%. The broadband transport efficiency was 11%
Synthesis and magnetic characterizations of uniform iron oxide nanoparticles
International Nuclear Information System (INIS)
Jiang, FuYi; Li, XiaoYi; Zhu, Yuan; Tang, ZiKang
2014-01-01
Uniform iron oxide nanoparticles with a cubic shape were prepared by the decomposition of homemade iron oleate in 1-octadecene with the presence of oleic acid. The particle shape and size uniformity are sensitive to the quantity of oleic acid. XRD, HRTEM and SAED results indicated that the main phase content of as-prepared iron oxide nanoparticles is Fe 3 O 4 with an inverse spinel structure. Magnetic measurements revealed that the as-prepared iron oxide nanoparticles display a ferromagnetic behavior with a blocking temperature of 295 K. At low temperatures the magnetic anisotropy of the aligned nanoparticles caused the appearance of a hysteresis loop.
Entropy generation in MHD flow of a uniformly stretched vertical ...
African Journals Online (AJOL)
This paper reports the analytical calculation of the entropy generation due to heat and mass transfer and fluid friction in steady state of a uniformly stretched vertical permeable surface with heat and mass diffusive walls, by solving analytically the mass, momentum, species concentration and energy balance equation, using ...
Highly Uniform Epitaxial ZnO Nanorod Arrays for Nanopiezotronics
Directory of Open Access Journals (Sweden)
Nagata T
2009-01-01
Full Text Available Abstract Highly uniform and c-axis-aligned ZnO nanorod arrays were fabricated in predefined patterns by a low temperature homoepitaxial aqueous chemical method. The nucleation seed patterns were realized in polymer and in metal thin films, resulting in, all-ZnO and bottom-contacted structures, respectively. Both of them show excellent geometrical uniformity: the cross-sectional uniformity according to the scanning electron micrographs across the array is lower than 2%. The diameter of the hexagonal prism-shaped nanorods can be set in the range of 90–170 nm while their typical length achievable is 0.5–2.3 μm. The effect of the surface polarity was also examined, however, no significant difference was found between the arrays grown on Zn-terminated and on O-terminated face of the ZnO single crystal. The transmission electron microscopy observation revealed the single crystalline nature of the nanorods. The current–voltage characteristics taken on an individual nanorod contacted by a Au-coated atomic force microscope tip reflected Schottky-type behavior. The geometrical uniformity, the designable pattern, and the electrical properties make the presented nanorod arrays ideal candidates to be used in ZnO-based DC nanogenerator and in next-generation integrated piezoelectric nano-electromechanical systems (NEMS.
Electromagnetic Radiation in a Uniformly Moving, Homogeneous Medium
DEFF Research Database (Denmark)
Johannsen, Günther
1972-01-01
A new method of treating radiation problems in a uniformly moving, homogeneous medium is presented. A certain transformation technique in connection with the four-dimensional Green's function method makes it possible to elaborate the Green's functions of the governing differential equations...
A charged black hole in a uniform magnetic field
International Nuclear Information System (INIS)
Krori, K.D.; Chaudhury, S.; Dowerah, S.
1983-01-01
We present here an investigation of the event horizon of a charged black hole embedded in a uniform magnetic field studying the Gaussian curvature. It is shown that the Gauss-Bonnet theorem holds for this magnetized black hole and for a magnetized Kerr black hole
Perceived Articulation Uniformity between Trumpet and Violin Performances
Cooper, Shelly C.; Hamann, Donald L.
2010-01-01
Directors strive for a unified sound throughout their wind and orchestra ensembles. Articulation affects sound uniformity among winds and strings. This baseline study examined whether a trumpet player could better match a violin player's articulation, as perceived by participants listening to a recording of two performances, when: (a) performing…
Uniform and Complementary Social Interaction: Distinct Pathways to Solidarity.
Koudenburg, Namkje; Postmes, Tom; Gordijn, Ernestine H; van Mourik Broekman, Aafke
2015-01-01
We examine how different forms of co-action give rise to feelings of solidarity. We propose that (a) coordinated action elicits a sense of solidarity, and (b) the process through which such solidarity emerges differs for different forms of co-action. We suggest that whether solidarity within groups emerges from uniform action (e.g. synchronizing, as when people speak in unison) or from more complementary forms of action (e.g. alternating, when speaking in turns) has important consequences for the emergent position of individuals within the group. Uniform action relies on commonality, leaving little scope for individuality. In complementary action each individual makes a distinctive contribution to the group, thereby increasing a sense of personal value to the group, which should contribute to the emergence of solidarity. The predictions receive support from five studies, in which we study groups in laboratory and field settings. Results show that both complementary and uniform co-action increase a sense of solidarity compared to control conditions. However, in the complementary action condition, but not in the uniform action (or synchrony) condition, the effect on feelings of solidarity is mediated by a sense of personal value to the group.
Consensus in the network with uniform constant communication delay
Wang, Xu; Saberi, Ali; Stoorvogel, Antonie Arij; Grip, H°avard Fjær; Yang, Tao
2013-01-01
This paper studies consensus among identical agents that are at most critically unstable and coupled through networks with uniform constant communication delay. An upper bound for delay tolerance is obtained which explicitly depends on agent dynamics and network topology. The dependence on network
Uniforms in Public Schools: A Decade of Research and Debate
Brunsma, David L.
2005-01-01
Contrary to what one reads in the headlines and texts of the nation's most prominent newspapers, what one hears from the mouths of politicians and educational administrators, and what one sees on the evening news, there is absolutely nothing simplistic and straightforward about the current movement to uniform public school students in the United…
Gamma-ray monitor for plutonium uniformity in fuel tubes
International Nuclear Information System (INIS)
Winn, W.G.
1981-01-01
Plutonium fuel tubes must be examined for abnormal PuO 2 densities. A fuel-gamma densitometer (FGD) was developed to measure the PuO 2 content within 3.2-mm-diameter areas. The FGD measurement of hot spot densities is an extension of the usual gamma-scanner application of verifying fuel uniformity within a few percent
On locally uniformly linearizable high breakdown location and scale functionals
Davies, P.L.
1998-01-01
This article gives two constructions of a weighted mean which has a large domain, is affinely equivariant, has a locally high breakdown point and is locally uniformly linearizable. One construction is based on $M$-functionals with smooth defining $\\psi$- and $\\chi$ -functions which are used to
Stability of common fixed points in uniform spaces
Directory of Open Access Journals (Sweden)
Singh Shyam
2011-01-01
Full Text Available Abstract Stability results for a pair of sequences of mappings and their common fixed points in a Hausdorff uniform space using certain new notions of convergence are proved. The results obtained herein extend and unify several known results. AMS(MOS Subject classification 2010: 47H10; 54H25.
Uniform convergence of the empirical spectral distribution function
Mikosch, T; Norvaisa, R
1997-01-01
Let X be a linear process having a finite fourth moment. Assume F is a class of square-integrable functions. We consider the empirical spectral distribution function J(n,X) based on X and indexed by F. If F is totally bounded then J(n,X) satisfies a uniform strong law of large numbers. If, in
Casimir energy for twisted piecewise uniform bosonic strings
International Nuclear Information System (INIS)
Lu, J.; Huang, B.; Shanghai, Teachers Univ.
1998-01-01
The Casimir energy for the transverse oscillations of piecewise uniform bosonic strings with either untwisted or twisted continuous conditions is discussed. After calculating the analytic values of zeros of the dispersion function under certain conditions, is obtained the Casimir energy for both open and closed bosonic strings composed of two or three segments
48 CFR 14.201-1 - Uniform contract format.
2010-10-01
... regulation that are inconsistent with the uniform contract format. (5) Firm-fixed-price or fixed-price with economic price adjustment acquisitions that use the simplified contract format (see 14.201-9). (b... shall retain it in the contract file. (See 4.1201(c).) Award by acceptance of a bid on the award portion...
Power dependence of supercontinuum noise in uniform and tapered PCFs
DEFF Research Database (Denmark)
Møller, Uffe; Sørensen, Simon Toft; Jakobsen, C.
2012-01-01
We experimentally investigate the noise properties of picosecond supercontinuum spectra generated at different power levels in uniform and tapered photonic crystal fibers. We show that the noise at the spectral edges of the generated supercontinuum is at a constant level independent on the pump...
75 FR 71344 - Uniform Compliance Date for Food Labeling Regulations
2010-11-23
.... FSIS-2010-0031] RIN 0583-AD Uniform Compliance Date for Food Labeling Regulations AGENCY: Food Safety... regulations that require changes in the labeling of meat and poultry food products. Many meat and poultry... for new food labeling regulations is consistent with FDA's approach in this regard. FDA is also...
Uniform and Complementary Social Interaction: Distinct Pathways to Social Unity.
Koudenburg, Namkje; Postmes, Tom; Gordijn, Ernestine; van Mourik Broekman, Aafke
We examine how different forms of co-action (uniform vs. complementary co-action) give rise to feelings of solidarity. Five studies reveal that both forms of co-action increase solidarity, but have different consequences for the role of the individual within the group.
Spiking mode operation for a uniform-period wiggler
International Nuclear Information System (INIS)
Warren, R.W.; Goldstein, J.C.; Newnam, B.E.
1985-01-01
The onset of saturation in a uniform-period wiggler has been examined experimentally and through numerical simulations. Models have been constructed that explain the observations in simple and consistent ways. The models are based upon the development of strong frequency and amplitude modulation of the optical wave as a way to increase extraction efficiency and optical power
Exact Finite Differences. The Derivative on Non Uniformly Spaced Partitions
Directory of Open Access Journals (Sweden)
Armando Martínez-Pérez
2017-10-01
Full Text Available We define a finite-differences derivative operation, on a non uniformly spaced partition, which has the exponential function as an exact eigenvector. We discuss some properties of this operator and we propose a definition for the components of a finite-differences momentum operator. This allows us to perform exact discrete calculations.
Multiplier convergent series and uniform convergence of mapping ...
Indian Academy of Sciences (India)
MS received 14 April 2011; revised 17 November 2012. Abstract. In this paper, we introduce the frame property of complex sequence sets and study the uniform convergence of nonlinear mapping series in β-dual of spaces consisting of multiplier convergent series. Keywords. Multiplier convergent series; mapping series. 1.
Uniform deposition of size-selected clusters using Lissajous scanning
International Nuclear Information System (INIS)
Beniya, Atsushi; Watanabe, Yoshihide; Hirata, Hirohito
2016-01-01
Size-selected clusters can be deposited on the surface using size-selected cluster ion beams. However, because of the cross-sectional intensity distribution of the ion beam, it is difficult to define the coverage of the deposited clusters. The aggregation probability of the cluster depends on coverage, whereas cluster size on the surface depends on the position, despite the size-selected clusters are deposited. It is crucial, therefore, to deposit clusters uniformly on the surface. In this study, size-selected clusters were deposited uniformly on surfaces by scanning the cluster ions in the form of Lissajous pattern. Two sets of deflector electrodes set in orthogonal directions were placed in front of the sample surface. Triangular waves were applied to the electrodes with an irrational frequency ratio to ensure that the ion trajectory filled the sample surface. The advantages of this method are simplicity and low cost of setup compared with raster scanning method. The authors further investigated CO adsorption on size-selected Pt n (n = 7, 15, 20) clusters uniformly deposited on the Al 2 O 3 /NiAl(110) surface and demonstrated the importance of uniform deposition.
Uniform deposition of size-selected clusters using Lissajous scanning
Energy Technology Data Exchange (ETDEWEB)
Beniya, Atsushi; Watanabe, Yoshihide, E-mail: e0827@mosk.tytlabs.co.jp [Toyota Central R& D Labs., Inc., 41-1 Yokomichi, Nagakute, Aichi 480-1192 (Japan); Hirata, Hirohito [Toyota Motor Corporation, 1200 Mishuku, Susono, Shizuoka 410-1193 (Japan)
2016-05-15
Size-selected clusters can be deposited on the surface using size-selected cluster ion beams. However, because of the cross-sectional intensity distribution of the ion beam, it is difficult to define the coverage of the deposited clusters. The aggregation probability of the cluster depends on coverage, whereas cluster size on the surface depends on the position, despite the size-selected clusters are deposited. It is crucial, therefore, to deposit clusters uniformly on the surface. In this study, size-selected clusters were deposited uniformly on surfaces by scanning the cluster ions in the form of Lissajous pattern. Two sets of deflector electrodes set in orthogonal directions were placed in front of the sample surface. Triangular waves were applied to the electrodes with an irrational frequency ratio to ensure that the ion trajectory filled the sample surface. The advantages of this method are simplicity and low cost of setup compared with raster scanning method. The authors further investigated CO adsorption on size-selected Pt{sub n} (n = 7, 15, 20) clusters uniformly deposited on the Al{sub 2}O{sub 3}/NiAl(110) surface and demonstrated the importance of uniform deposition.
Communication Network Integration and Group Uniformity in a Complex Organization.
Danowski, James A.; Farace, Richard V.
This paper contains a discussion of the limitations of research on group processes in complex organizations and the manner in which a procedure for network analysis in on-going systems can reduce problems. The research literature on group uniformity processes and on theoretical models of these processes from an information processing perspective…
Post-Buckling Strength of Uniformly Compressed Plates
Bakker, M.C.M.; Rosmanit, M.; Hofmeyer, H.; Camotim, D; Silvestre, N; Dinis, P.B.
2006-01-01
In this paper it is discussed how existing analytical and semi-analytical formulas for describing the elastic-post-buckling behavior of uniformly compressed square plates with initial imperfections, for loads up to three times the buckling load can be simplified and improved. For loads larger than
Does Blue Uniform Color Enhance Winning Probability in Judo Contests?
Dijkstra, P.D.; Preenen, P.T.Y.; Essen, H. van
2018-01-01
The color of an athlete's uniform may have an effect on psychological functioning and consequently bias the chances of winning contests in sport competition. Several studies reported a winning bias for judo athletes wearing a blue outfit relative to those wearing a white outfit. However, we argue
Remarks on Hawking radiation as tunneling from a uniformly ...
Indian Academy of Sciences (India)
Abstract. Motivated by the Hamilton–Jacobi method of Angheben et al, we investigate the Hawking tunneling radiation from a uniformly accelerating rectilinear black hole for which the horizons and entropy are functions of θ. After several coordinate transforma- tions, we conclude that when the self-gravitational interaction ...
Optimizing the LSST Dither Pattern for Survey Uniformity
Awan, Humna; Gawiser, Eric J.; Kurczynski, Peter; Carroll, Christopher M.; LSST Dark Energy Science Collaboration
2015-01-01
The Large Synoptic Survey Telescope (LSST) will gather detailed data of the southern sky, enabling unprecedented study of Baryonic Acoustic Oscillations, which are an important probe of dark energy. These studies require a survey with highly uniform depth, and we aim to find an observation strategy that optimizes this uniformity. We have shown that in the absence of dithering (large telescope-pointing offsets), the LSST survey will vary significantly in depth. Hence, we implemented various dithering strategies, including random and repulsive random pointing offsets and spiral patterns with the spiral reaching completion in either a few months or the entire ten-year run. We employed three different implementations of dithering strategies: a single offset assigned to all fields observed on each night, offsets assigned to each field independently whenever the field is observed, and offsets assigned to each field only when the field is observed on a new night. Our analysis reveals that large dithers are crucial to guarantee survey uniformity and that assigning dithers to each field independently whenever the field is observed significantly increases this uniformity. These results suggest paths towards an optimal observation strategy that will enable LSST to achieve its science goals.We gratefully acknowledge support from the National Science Foundation REU program at Rutgers, PHY-1263280, and the Department of Energy, DE-SC0011636.
Fabrication and Performance Study of Uniform Thin Film Integrated ...
African Journals Online (AJOL)
The transmission line model of a uniform rectangular thin film R-C-KR structure consisting of a dielectric layer of constant per unit shunt capacitance C sandwiched between two resistive thin films of constant per unit length resistances R and KR has been analysed using the concept of matrix parameter functions. The above ...
Crystallographically uniform arrays of ordered (In)GaN nanocolumns
Energy Technology Data Exchange (ETDEWEB)
Gačević, Ž., E-mail: gacevic@isom.upm.es; Bengoechea-Encabo, A.; Albert, S.; Calleja, E. [ETSIT-ISOM, Universidad Politécnica de Madrid, Avda. Complutense s/n, 28040 Madrid (Spain); Torres-Pardo, A.; González-Calbet, J. M. [Dept. Química Inorgánica, Universidad Complutense, 28040 Madrid (Spain); CEI Campus Moncloa, UCM-UPM, Madrid (Spain)
2015-01-21
In this work, through a comparative study of self-assembled (SA) and selective area grown (SAG) (In)GaN nanocolumn (NC) ensembles, we first give a detailed insight into improved crystallographic uniformity (homogeneity of crystallographic tilts and twists) of the latter ones. The study, performed making use of: reflective high energy electron diffraction, X-ray diffraction and scanning electron microscopy, reveals that unlike their SA counterparts, the ensembles of SAG NCs show single epitaxial relationship to both sapphire(0001) and Si(111) underlying substrates. In the second part of the article, making use of X-ray diffraction, we directly show that the selective area growth leads to improved compositional uniformity of InGaN NC ensembles. This further leads to improved spectral purity of their luminescence, as confirmed by comparative macro-photoluminescence measurements performed on SA and SAG InGaN NC ensembles. An improved crystallographic uniformity of NC ensembles facilitates their integration into optoelectronic devices, whereas their improved compositional uniformity allows for their employment in single-color optoelectronic applications.
Uniformity of plants regenerated from orange (Citrus sinensis Osb.) protoplasts.
Kobayashi, S
1987-05-01
Using 25 plants (protoclones) regenerated from orange (Citrus sinensis Osb.) protoplasts, several characters, including leaf and flower morphology, leaf oil, isozyme patterns and chromosome number, were examined. No significant variations in each character were recorded among the protoclones. Uniformity observed among protoclones was identical to that of nucellar seedlings.
Two forms for 3-uniform states of eight-qubits
Zha, Xinwei; Da, Zhang; Ahmed, Irfan; Zhang, Yanpeng
2018-05-01
In this paper, we study the relations between average bipartite entanglement and the n-tangle of eight-qubits. We have derived two forms for 3-uniform states of eight-qubits. One form has the n-tangle equal to zero; the other form has the n-tangle equal to unity.
Instruction sequences and non-uniform complexity theory
Bergstra, J.A.; Middelburg, C.A.
2008-01-01
We develop theory concerning non-uniform complexity in a setting in which the notion of single-pass instruction sequence considered in program algebra is the central notion. We define counterparts of the complexity classes P/poly and NP/poly and formulate a counterpart of the complexity theoretic
Experimental study on generation of large area uniform electron beam
International Nuclear Information System (INIS)
Tang Ying; Yi Aiping; Liu Jingru; Qian Hang; Huang Xin; Yu Li; Su Jiancang; Ding Zhenjie; Ding Yongzhong; Yu Jianguo
2007-01-01
In the experiment of gas laser pumped by electron beam, large area uniform electron beam is important to generate high efficiency laser output. The experimental study on generation of large area uniform electron beam with SPG-200 pulsed power generator is introduced. SPG-200 is an all-solid-state components pulsed power generator based on SOS, and its open voltage is more than 350 kV. The cathode have the area of 24 mm x 294 mm, and the anode-cathode(A-C)gap spacing is adjustable from 0 to 49 mm. The electron beam of cathode emission is transported to the laser chamber through the diode pressure foil, which sepa-rates the vacuum chamber from the laser chamber. Velvet and graphite cathodes are studied, each generates large area electron beam. The diode parameters are presented, and the uniformity of e-beam is diagnosed. The experimental results show that the diode voltage of the graphite cathode is 240-280 kV, and the diode current is 0.7-1.8 kA. The diode voltage of the velvet cathode is 200-250 kV, and the diode current is 1.5-1.7 kA. The uniformity of the velvet cathode emission is better than that of the graphite cathode. (authors)
Dressing symmetry of the uniformization solution of Liouville equation
International Nuclear Information System (INIS)
Shen Jianmin.
1994-10-01
In this paper, the relations between monodromy group and dressing group for Liouville equation in uniformization theorem are discussed. The representation of monodromy transformation, acting on the chiral components of the solution of Liouville equation, is obtained. The non-trivial exchange algebra for monodromy transformation is calculated. (author). 14 refs
Capacitated Vehicle Routing with Non-Uniform Speeds
DEFF Research Database (Denmark)
Gørtz, Inge Li; Molinaro, Marco; Nagarajan, Viswanath
2011-01-01
-uniform speeds (that we call Heterogenous CVRP), and present a constant-factor approximation algorithm. The technical heart of our result lies in achieving a constant approximation to the following TSP variant (called Heterogenous TSP). Given a metric denoting distances between vertices, a depot r containing k...
MHD flow of a uniformly stretched vertical permeable membrane in ...
African Journals Online (AJOL)
We present a magneto - hydrodynamic flow of a uniformly stretched vertical permeable surface undergoing Arrhenius heat reaction. The analytical solutions are obtained for concentration, temperature and velocity fields using an asymptotic approximation, similar to that of Ayeni et al 2004. It is shown that the temperature ...
Leveraging Non-Uniform Resources for Parallel Query Processing
DEFF Research Database (Denmark)
Mayr, Tobias; Bonnet, Philippe; Gehrke, Johannes
2003-01-01
Modular clusters are now composed of non- uniform nodes with different CPUs, disks or network cards so that customers can adapt the cluster configuration to the changing technologies and to their changing needs. This challenges dataflow parallelism as the primary load balancing technique of exist...
van Woerkom, M.; de Bruijn, M.J.
Dissatisfaction with performance appraisal is at an all-time high (Adler et al., 2016). In this commentary we argue that one of the reasons why performance appraisal is unable to get the most out of employees is the way in which employees are evaluated against a uniform set of criteria, leading to a
A. Gil (Amparo); J. Segura (Javier); N.M. Temme (Nico)
2002-01-01
textabstractThe use of a uniform Airy-type asymptotic expansion for the computation of the modified Bessel functions of the third kind of imaginary orders ($K_{ia}(x)$) near the transition point $x=a$, is discussed. In [2], an algorithm for the evaluation of $K_{ia}(x)$ was presented, which made use
Design of a collector shape for uniform flow distribution in microchannels
International Nuclear Information System (INIS)
Siddique, Ayyaz; Agrawal, Amit; Saha, Sandip K; Medhi, Bhaskar J; Singh, Anugrah
2017-01-01
The focus of this study is the design of a collector with the objective of achieving uniform flow in multiple parallel microchannels. This objective is achieved by understanding the limitations of current designs and a novel design is proposed, which is further carefully optimized. The existing collector shape considered is U-type, which is investigated numerically. The creation of a stagnation zone, growth of a boundary layer along the collector wall and low/high velocity zones in the collector are identified as the prime causes of flow maldistribution. A novel design, a dumbbell shape collector, is proposed to overcome the limitations of the earlier designs. The dumbbell shape is evaluated quantitatively and is found to perform better than all existing shapes. This dumbbell shape collector provides a uniform flow distribution with less than 0.4% relative difference from the average flow rate in different channels, which is substantially better than existing collectors with 2.3% relative difference from the average flow rate for Re ch = 32. The uniformity is further confirmed using micro-particle image velocimetry measurements. The dumbbell shape collector is generalized and optimized to cater to heat sinks of different dimensions and to broaden its applicability in both micro and macro dimensions. (paper)
Uniform, stable supply of medium for in vitro cell culture using a robust chamber
Wei, Juan; Liu, Chong; Jiang, Yang; Liu, Tao; Chen, Li; Liu, Bo; Li, Jingmin
2018-06-01
A uniform, stable supply of medium is important for in vitro cell culture. In this paper, a microfluidic device is presented for culturing cells inside a robust chamber with continuous perfusion of medium. The device consists of a main channel, two bifurcated channels and a culture chamber. The culture chamber connects to the bifurcated channels via multiple paths, and distributes symmetrically on the main channel, to improve the efficiency of medium exchange. Furthermore, regular polygonal chambers with various numbers of edges have been designed, to study the effects of chamber shape on flow fields. The finite element method has been employed to predict the effects of multiple paths on the uniformity and stability of flow fields in the culture chamber. Particle tracking technology has been used to evaluate the flow fields in the chambers, and PC-12 cells have been cultured using the microfluidic device, to test its validity. The results of simulation and experiment indicate that the microfluidic design could provide a continuous interstitial-like flow microenvironment, with a relatively stable and uniform supply of medium.
Development of uniform eddy current multi-probe for flaw detection on complex shape part
International Nuclear Information System (INIS)
Fukuoka, Katsuhiro; Hashimoto, Mitsuo
2007-01-01
The establishment of the technology that inspects plant structures nondestructive is requested, because the occurrence of cracks is reported in the structures of nuclear power plants. In this research, a uniform eddy current multi-probe that is able to be applied to the complex structure and inspected the cracks at the high speed was developed. Exciting coils of the uniform eddy current multi-probe were designed the shape that agreed with the complex shape part, and so that the eddy current flows uniformly in the part of pick-up coils. The pick-up coils were arranged on a flexible printed circuit board as it was possible to correspond to the complex shape. The detection characteristics of EDM (electro-discharge machining) slits provided on the complex shape part were evaluated. The clear signals for the EDM slits provided on the curvature surface of 25 mm in radius were obtained by this probe. We confirmed that the crack shape was able to be estimated by the detection signals. (author)
Djakou, Audrey Kamta; Darmon, Michel; Fradkin, Larissa; Potel, Catherine
2015-11-01
Diffraction phenomena studied in electromagnetism, acoustics, and elastodynamics are often modeled using integrals, such as the well-known Sommerfeld integral. The far field asymptotic evaluation of such integrals obtained using the method of steepest descent leads to the classical Geometrical Theory of Diffraction (GTD). It is well known that the method of steepest descent is inapplicable when the integrand's stationary phase point coalesces with its pole, explaining why GTD fails in zones where edge diffracted waves interfere with incident or reflected waves. To overcome this drawback, the Uniform geometrical Theory of Diffraction (UTD) has been developed previously in electromagnetism, based on a ray theory, which is particularly easy to implement. In this paper, UTD is developed for the canonical elastodynamic problem of the scattering of a plane wave by a half-plane. UTD is then compared to another uniform extension of GTD, the Uniform Asymptotic Theory (UAT) of diffraction, based on a more cumbersome ray theory. A good agreement between the two methods is obtained in the far field.
International Nuclear Information System (INIS)
Toelli, H.; Bielajew, A. F.; Mattsson, O.; Sernbo, G.
1995-01-01
When ionization chambers are used in brachytherapy dosimetry, the measurements must be corrected for the non-uniformity of the incident photon fluence. The theory for determination of non-uniformity correction factors, developed by Kondo and Randolph (Rad. Res. 1960) assumes that the electron fluence within the air cavity is isotropic and does not take into account material differences in the chamber wall. The theory was extended by Bielajew (PMB 1990) using an anisotropic electron angular fluence in the cavity. In contrast to the theory by Kondo and Randolph, the anisotropic theory predicts a wall material dependence in the non-uniformity correction factors. This work presents experimental determination of non-uniformity correction factors at distances between 10 and 140 mm from an Ir-192 source. The experimental work makes use of a PTW23331-chamber and Farmer-type chambers (NE2571 and NE2581) with different materials in the walls. The results of the experiments agree well with the anisotropic theory. Due to the geometrical shape of the NE-type chambers, it is shown that the full length of the these chambers, 24.1mm, is not an appropriate input parameter when theoretical non-uniformity correction factors are evaluated
Buttoned down: Are School Uniform Policies a Perfect Fit for All Students?
Messitt, Maggie
2013-01-01
In the 1999-2000 school year, only about 12 percent of U.S. public schools required their students to wear uniforms. Since then, the number of schools requiring uniforms has risen. Uniform policies are now in place at about a fifth of all public schools in the United States--but do school uniforms really level the playing field? New research has…
Nurses' uniform color and feelings/emotions in school-aged children receiving health care.
Albert, Nancy M; Burke, Jane; Bena, James F; Morrison, Shannon M; Forney, Jennifer; Krajewski, Susan
2013-04-01
Children may fear nurses wearing white uniforms. When emotions and uniform color were studied in 233 children, many positive emotions were most often associated with blue, bold pink-patterned, or yellow-patterned tops (all p ≤ .002). Negative emotions were not associated with uniform top colors (all p uniform color does not matter," 8 negative emotions were most often associated with white uniform color (p uniform tops were preferred. In conclusion, children's emotions were associated with nurse uniform color. Copyright © 2013 Elsevier Inc. All rights reserved.
The existence of panchromatic colourings for uniform hypergraphs
International Nuclear Information System (INIS)
Shabanov, Dmitrii A
2010-01-01
The well-known extremal problem concerning panchromatic colouring of hypergraphs is investigated. An r-colouring of the set of vertices of a hypergraph is said to be panchromatic if each link of the hypergraph is incident to vertices of all colours. The quantity p(n,r) defined as the minimum number of links in an n-uniform hypergraph which admits no panchromatic r-colourings is studied. New lower and upper bounds for p(n,r) are obtained, which improve earlier results for many of the relations between the parameters n and r. In addition, a sufficient condition for the existence of a panchromatic r-colouring of an n-uniform hypergraph is obtained. Bibliography: 18 items.
Uniformity of material in the SME and MFT
International Nuclear Information System (INIS)
Plodinec, M.J.
1992-01-01
The DWPF will satisfy the product consistency specification in the Waste Acceptance Preliminary Specifications through control of the chemical composition of the glass product. This control will be achieved by ensuring that each batch of feed in the Slurry Mix Evaporator (SME) will produce glass which satisfies the specification. The purpose of this report is to determine what degree of uniformity can be expected of material in the SME and Metter Feed Tank (MFT). These vessels were designed based on a design development process which had proven successful for similar hard-to-mix feeds in the past. This process resulted in a design of the SME and MFT agitation systems which was intended to provide highly uniform melter feed material. Based on the results of extensive tests in protoypic equipment, the SME and MFT designs have met this design goal
Dynamical chaos and uniformly hyperbolic attractors: from mathematics to physics
Energy Technology Data Exchange (ETDEWEB)
Kuznetsov, Sergei P [Saratov Branch, Kotel' nikov Institute of Radio Engineering and Electronics, Russian Academy of Sciences, Saratov (Russian Federation)
2011-02-28
Research is reviewed on the identification and construction of physical systems with chaotic dynamics due to uniformly hyperbolic attractors (such as the Plykin attraction or the Smale-Williams solenoid). Basic concepts of the mathematics involved and approaches proposed in the literature for constructing systems with hyperbolic attractors are discussed. Topics covered include periodic pulse-driven models; dynamics models consisting of periodically repeated stages, each described by its own differential equations; the construction of systems of alternately excited coupled oscillators; the use of parametrically excited oscillations; and the introduction of delayed feedback. Some maps, differential equations, and simple mechanical and electronic systems exhibiting chaotic dynamics due to the presence of uniformly hyperbolic attractors are presented as examples. (reviews of topical problems)
Achieving uniform efficient illumination with multiple asymmetric compound parabolic luminaires
Gordon, Jeffrey M.; Kashin, Peter
1994-01-01
Luminaire designs based on multiple asymmetric nonimaging compound parabolic reflectors are proposed for 2-D illumination applications that require highly uniform far-field illuminance, while ensuring maximal lighting efficiency and sharp angular cutoffs. The new designs derive from recent advances in nonimaging secondary concentrators for line-focus solar collectors. The light source is not treated as a single entity, but rather is divided into two or more separate adjoining sources. An asymmetric compound parabolic luminaire is then designed around each half-source. Attaining sharp cutoffs requires relatively large reflectors. However, severe truncation of the reflectors renders these devices as compact as many conventional luminaires, at the penalty of a small fraction of the radiation being emitted outside the nominal cutoff. The configurations that maximize the uniformity of far-field illuminance offer significant improvements in flux homogeneity relative to alternative designs to date.
Magnetic fluid bridge in a non-uniform magnetic field
International Nuclear Information System (INIS)
Pelevina, D.A.; Naletova, V.A.; Turkov, V.A.
2017-01-01
The shape of a magnetic fluid bridge between a horizontal ferrite rod of circular cross-section and a horizontal plate above the rod in a vertical applied uniform magnetic field is studied. Various static shapes of the bridges are obtained theoretically and experimentally for the same magnetic field value. Abrupt changes and the hysteresis of the bridge shape in alternating magnetic fields are observed experimentally. - Highlights: • Magnetic fluid bridge between rod and horizontal plate in magnetic field is studied. • Magnetic field is created by a ferrite rod in a uniform vertical magnetic field. • Various static bridge shapes for fixed field are obtained in theory and experiment. • A good agreement of experimental and theoretical results is obtained. • Hysteresis of the bridge shape in alternating field is observed experimentally.
Dynamics of leaching a uniformly fissured ore body
International Nuclear Information System (INIS)
Ignatov, A.A.; Proskurin, S.A.
1987-01-01
Mathematical simulation was used to study the dynamics of mass transfer during the percolation of a reagent solution through a packing of coarse ore particles. The uniformly fissured ore body was represented by a cubic packing of spherical particles of constant radius, formed from a chemically inert silicate cement with a uniformly distributed soluble mineral component. The rate of percolation of the reagent through the packing was constant. The proposed model can be used to find the conditions for underground hydrodynamic leaching. The rate of non-catalytic solid-liquid reaction was deduced on the basis of both the kinetics of dissolution of the mineral component of the ore and the rate of diffusion of the dissolved substance
Deviations from uniform power law scaling in nonstationary time series
Viswanathan, G. M.; Peng, C. K.; Stanley, H. E.; Goldberger, A. L.
1997-01-01
A classic problem in physics is the analysis of highly nonstationary time series that typically exhibit long-range correlations. Here we test the hypothesis that the scaling properties of the dynamics of healthy physiological systems are more stable than those of pathological systems by studying beat-to-beat fluctuations in the human heart rate. We develop techniques based on the Fano factor and Allan factor functions, as well as on detrended fluctuation analysis, for quantifying deviations from uniform power-law scaling in nonstationary time series. By analyzing extremely long data sets of up to N = 10(5) beats for 11 healthy subjects, we find that the fluctuations in the heart rate scale approximately uniformly over several temporal orders of magnitude. By contrast, we find that in data sets of comparable length for 14 subjects with heart disease, the fluctuations grow erratically, indicating a loss of scaling stability.
Ethics, law, and commercial surrogacy: a call for uniformity.
Drabiak, Katherine; Wegner, Carole; Fredland, Valita; Helft, Paul R
2007-01-01
In the United States at this time, no uniform federal law exists regarding commercial surrogacy, and state statutory schemes vary vastly, ranging from criminalization to legal recognition with contract enforcement. The authors examine how commercial surrogacy agencies utilize the Internet as a means for attracting parents and surrogates by employing emotional cultural rhetoric. By inducing both parents and surrogates to their jurisdiction, agencies circumvent vast discrepancies in state statutory regulative schemes and create a distinct interstate business, absent an efficient regulatory framework or legal recourse in some circumstances. The authors propose a uniform federal regulatory scheme premised upon regulating interstate business transactions to create accountability and legal remedies for both the parents and the surrogate.
Uniform electromagnetic field as viscous medium for moving particles
International Nuclear Information System (INIS)
Amusia, M.Ya.; Baltenkov, A.S.; Felfli, Z.; Msezane, A.Z.; Voitkiv, A.B.
2002-01-01
The mechanism of transverse radiation viscosity acting on free charges, atomic, and small macroscopic particles in uniform electromagnetic fields is analyzed. It is shown that in the process of light scattering by these particles, besides the force accelerating them in the direction of propagation of the radiation, there is a force in the transverse direction slowing them down. The general expression for this force is obtained. It is considered how this force can influence: (i) the motion of ultrarelativistic electrons in transverse photon fluxes; (ii) the behavior of a beam of nonrelativistic electrons moving in a copropagating uniform electromagnetic field; (iii) the transverse motion of atoms under the action of resonant radiation and (iv) the motion of small macroscopic particles
Uniformity in radon exhalation from construction materials using can technique
Energy Technology Data Exchange (ETDEWEB)
El-Amri, E.A.; Al-Jarallah, M.I. E-mail: mibrahim@kfupm.edu.sa; Abu-Jarad, F.; Fazal-ur-Rehman
2003-06-01
The uniformity in radon exhalation rates for 46 tiles of granite, marble and ceramic used as construction materials were determined using 'Can Technique' employing CR-39 nuclear track detectors (NTDs). On each tile, two sealed cans, each enclosing one NTD fixed at the center of the tile surface area covered by the can, were mounted at two different locations of each individual tiles. The track production rates on the NTDs representing radon exhalation rates were measured. The radon exhalation rates from the surface of individual tiles showed uniform exhalations within the calculated uncertainties of the measured values. This makes Can Technique an alternative simple method to measure radon exhalation rates. Calibration required to convert track production rates into radon exhalation rates for the used can and NTD was done using an active technique. The correlation between the measurements by the two techniques shows a good linear correlation coefficient (0.83)
Magnetic fluid bridge in a non-uniform magnetic field
Energy Technology Data Exchange (ETDEWEB)
Pelevina, D.A., E-mail: pelevina.daria@gmail.com; Naletova, V.A.; Turkov, V.A.
2017-06-01
The shape of a magnetic fluid bridge between a horizontal ferrite rod of circular cross-section and a horizontal plate above the rod in a vertical applied uniform magnetic field is studied. Various static shapes of the bridges are obtained theoretically and experimentally for the same magnetic field value. Abrupt changes and the hysteresis of the bridge shape in alternating magnetic fields are observed experimentally. - Highlights: • Magnetic fluid bridge between rod and horizontal plate in magnetic field is studied. • Magnetic field is created by a ferrite rod in a uniform vertical magnetic field. • Various static bridge shapes for fixed field are obtained in theory and experiment. • A good agreement of experimental and theoretical results is obtained. • Hysteresis of the bridge shape in alternating field is observed experimentally.
Effect of sprinkler structure on water distribution uniformity
International Nuclear Information System (INIS)
Xu, M; Li, H; Chen, C; Tu, Q; Liu, J P
2012-01-01
Structures of sprinklers play important roles in the uniformity of water distribution. The advances and achievements to improve the distribution uniformity through the innovation in the sprinkler structures at home and abroad were presented in details. Analyses showed that three types of structure can ameliorate the water distribution efficiently. First, novel nozzle structures were applied, including the application of non-circle nozzle and special spread nozzles. Second, new structures of flow channel were used. Third, assistant device was added so as to improve the uneven water distribution, such as an assistant stream interrupter, pressure or flow rate regulator and so on. Compared to domestic sprinklers, sprinklers produced abroad have novel and special structures with better hydraulic performance. Basic theoretical researches should be strengthened and new materials, new manufacturing processes and new technique should be applied. Then new kinds of sprinkler will be produced and the hydraulic performance of sprinklers will be promoted to a higher level.
Non-uniformity measurements of PbWO4 crystals
International Nuclear Information System (INIS)
Depasse, P.; Ernenwein, J.P.; Ille, B.; Martin, F.; Rosset, C.; Zach, F.
1998-11-01
Two independent methods have been used to measure the longitudinal non-uniformity scintillation response of 3 different (23-cm long) PbWO 4 crystals. The first one is the classical 60 Co source method. The source is collimated along the crystal, each 1,5-cm, and the scintillation signal is measured with a photomultiplier (a hybrid photomultiplier in our case). The second one is the use of cosmic particles (Minimum Ionizing Particles). A cosmic bench allows reconstructing the track of the MIP's and thus the energy deposit with the help of a full GEANT simulation of the setup. Variations of E along the crystal artificially cut in 1,5-cm divisions, leads to determine the non-uniformity. The conclusion is that both methods agree quite well. Furthermore, a good estimation of crystal light yield can be obtained. (author)
Electrostatic lens to focus an ion beam to uniform density
International Nuclear Information System (INIS)
Johnson, C.H.
1977-01-01
A focusing lens for an ion beam having a gaussian or similar density profile is described. The lens is constructed to provide an inner zero electrostatic field, and an outer electrostatic field such that ions entering this outer field are deflected by an amount that is a function of their distance from the edge of the inner field. The result is a beam that focuses to uniform density in a manner analogous to that of an optical ring lens. In one embodiment, a conically-shaped network of fine wires is enclosed within a cylindrical anode. The wire net together with the anode produces a voltage field that re-directs the outer particles of the beam while the axial particles pass undeflected through a zero field inside the wire net. The result is a focused beam having a uniform intensity over a given target area and at a given distance from the lens
Fabrication of Slanted Cu Nanopillars with Uniform Arrays
Directory of Open Access Journals (Sweden)
Sung-Woon Cho
2016-02-01
Full Text Available Slanted Cu nanopillars with uniform arrays were fabricat‐ ed using slanted Si channel structures as templates. A slanted plasma etching technique was employed, utilizing a Faraday cage system for the formation of these slanted channel structures. The angle of the slanted channel structures was accurately controlled because ions entering the Faraday cage maintained their direction. After the slanted channel structures were formed, they were filled with Cu by electroless deposition. Chemical mechanical polishing was then used to remove the excess Cu film and the SiO2 masks. Finally, the remaining poly Si of the channel structures was removed by wet chemical etching. This work offers a novel method for the fabrication of slanted metal nanostructures with uniform arrays covering a large area.
Non-uniformity of phase structure in immiscible polymer blends
Czech Academy of Sciences Publication Activity Database
Fortelný, Ivan; Lapčíková, Monika; Lednický, František; Starý, Zdeněk; Kruliš, Zdeněk
2008-01-01
Roč. 48, č. 3 (2008), s. 564-571 ISSN 0032-3888 R&D Projects: GA ČR GA106/06/0729; GA ČR GA106/06/0761 Institutional research plan: CEZ:AV0Z40500505 Keywords : polymer blends * melt mixing * non-uniform morphology Subject RIV: CD - Macromolecular Chemistry Impact factor: 1.245, year: 2008
Uniform separation of plastic wastes; Sortenreine Trennung von Kunststoffabfaellen
Energy Technology Data Exchange (ETDEWEB)
Eisenmann, R [Hochschule fuer Technik und Wirtschaft des Saarlandes, Saarbruecken (Germany)
1995-04-01
The position of raw material recycling is defined by comparison of different recycling levels. Means and limits of the main applicable methods for separating uniform plastic fractions from mixed wastes are summarized. (orig.) [Deutsch] Durch Vergleich der verschiedenen Recyclingebenen wird der Stellenwert des werkstofflichen Recycling bestimmt. Eine Zusammenfassung der wichtigsten derzeit verfuegbaren Verfahren zur Abtrennung sortenreiner Kunststoff-Fraktionen aus Abfallgemischen zeigt Moeglichkeiten und Grenzen der einzelnen Methoden. (orig.)
Optimal and online preemptive scheduling on uniformly related machines
Czech Academy of Sciences Publication Activity Database
Ebenlendr, Tomáš; Sgall, J.
2009-01-01
Roč. 12, č. 5 (2009), s. 517-527 ISSN 1094-6136 R&D Projects: GA MŠk(CZ) 1M0545; GA AV ČR IAA100190902; GA AV ČR IAA1019401 Institutional research plan: CEZ:AV0Z10190503 Keywords : online scheduling * preemption * uniformly related machines Subject RIV: IN - Informatics, Computer Science Impact factor: 1.265, year: 2009
Cantilever arrays with self-aligned nanotips of uniform height
International Nuclear Information System (INIS)
Koelmans, W W; Peters, T; Berenschot, E; De Boer, M J; Siekman, M H; Abelmann, L
2012-01-01
Cantilever arrays are employed to increase the throughput of imaging and manipulation at the nanoscale. We present a fabrication process to construct cantilever arrays with nanotips that show a uniform tip–sample distance. Such uniformity is crucial, because in many applications the cantilevers do not feature individual tip–sample spacing control. Uniform cantilever arrays lead to very similar tip–sample interaction within an array, enable non-contact modes for arrays and give better control over the load force in contact modes. The developed process flow uses a single mask to define both tips and cantilevers. An additional mask is required for the back side etch. The tips are self-aligned in the convex corner at the free end of each cantilever. Although we use standard optical contact lithography, we show that the convex corner can be sharpened to a nanometre scale radius by an isotropic underetch step. The process is robust and wafer-scale. The resonance frequencies of the cantilevers within an array are shown to be highly uniform with a relative standard error of 0.26% or lower. The tip–sample distance within an array of up to ten cantilevers is measured to have a standard error around 10 nm. An imaging demonstration using the AFM shows that all cantilevers in the array have a sharp tip with a radius below 10 nm. The process flow for the cantilever arrays finds application in probe-based nanolithography, probe-based data storage, nanomanufacturing and parallel scanning probe microscopy. (paper)
High-quality uniform dry transfer of graphene to polymers.
Lock, Evgeniya H; Baraket, Mira; Laskoski, Matthew; Mulvaney, Shawn P; Lee, Woo K; Sheehan, Paul E; Hines, Daniel R; Robinson, Jeremy T; Tosado, Jacob; Fuhrer, Michael S; Hernández, Sandra C; Walton, Scott G
2012-01-11
In this paper we demonstrate high-quality, uniform dry transfer of graphene grown by chemical vapor deposition on copper foil to polystyrene. The dry transfer exploits an azide linker molecule to establish a covalent bond to graphene and to generate greater graphene-polymer adhesion compared to that of the graphene-metal foil. Thus, this transfer approach provides a novel alternative route for graphene transfer, which allows for the metal foils to be reused. © 2011 American Chemical Society
A RICH with aerogel: a study of refractive index uniformity
Alemi, M; Calvi, M; Matteuzzi, C; Musy, M; Perego, D L; Easo, S
2004-01-01
The use of aerogel as a radiator in the RICH detectors of LHCb is a challenge due to the hot environment of the hadron collider LHC. Large size tiles of silica aerogel were recently produced with unprecedented optical quality for such dimensions. Results of laboratory measurements and beam tests are briefly reported. A description of a method to measure the uniformity of the index of refraction within the tile is given.
Uniform relativistic universe models with pressure. Part 2. Observational tests
International Nuclear Information System (INIS)
Krempec, J.; Krygier, B.
1977-01-01
The magnitude-redshift and angular diameter-redshift relations are discussed for the uniform (homogeneous and isotropic) relativistic Universe models with pressure. The inclusion of pressure into the energy-momentum tensor has given larger values of the deceleration parameter q. An increase of the deceleration parameter has led to the brightening of objects as well as to a little larger angular diameters. (author)
Pseudodifference operators and uniform convergence of divided differences
International Nuclear Information System (INIS)
Lifanov, I K; Poltavskii, L N
2002-01-01
The concept of pseudodifference operator is introduced. The properties of a class of pseudodifference operators in spaces of fractional quotients are studied. A local theorem on the uniform convergence of divided differences of arbitrary order for an approximate solution is established. In particular, the local infinite differentiability of a precise solution of operator equations of elliptic type with locally infinitely differentiable right-hand side is proved on the basis of a numerical method. Examples related to applications are presented
One-way Ponderomotive Barrier in a Uniform Magnetic Field
International Nuclear Information System (INIS)
Dodin, I.Y.; Fisch, N.J.
2005-01-01
The possibility of an asymmetric ponderomotive barrier in a nonuniform dc magnetic field by high-frequency radiation near the cyclotron resonance for selected plasma species was contemplated in Physics of Plasmas 11 (November 2004) 5046-5064. Here we show that a similar one-way barrier, which reflects particles incident from one side while transmitting those incident from the opposite side, can be produced also in a uniform magnetic field, entirely due to inhomogeneity of high-frequency drive
Applying a uniform marked morphism to a word
Directory of Open Access Journals (Sweden)
Anna Frid
1999-12-01
Full Text Available We describe the relationship between different parameters of the initial word and its image obtained by application of a uniform marked morphism. The functions described include the subword complexity, frequency of factors, and the recurrence function. The relations obtained for the image of a word can be used also for the image of a factorial language. Using induction, we give a full description of the involved functions of the fixed point of the morphism considered.
Uniform Bounds for Black--Scholes Implied Volatility
Tehranchi, Michael Rummine
2016-01-01
In this note, Black--Scholes implied volatility is expressed in terms of various optimization problems. From these representations, upper and lower bounds are derived which hold uniformly across moneyness and call price. Various symmetries of the Black--Scholes formula are exploited to derive new bounds from old. These bounds are used to reprove asymptotic formulas for implied volatility at extreme strikes and/or maturities. the Society for Industrial and Applied Mathematics 10.1137/14095248X
Uniform bounds for Black--Scholes implied volatility
Tehranchi, Michael R.
2015-01-01
In this note, Black--Scholes implied volatility is expressed in terms of various optimisation problems. From these representations, upper and lower bounds are derived which hold uniformly across moneyness and call price. Various symmetries of the Black--Scholes formula are exploited to derive new bounds from old. These bounds are used to reprove asymptotic formulae for implied volatility at extreme strikes and/or maturities.
Studying uniform thickness II: Transversely nonsimple iterated torus knots
DEFF Research Database (Denmark)
LaFountain, Douglas
2011-01-01
We prove that an iterated torus knot type in the standard contact 3-sphere fails the uniform thickness property (UTP) if and only if it is formed from repeated positive cablings, which is precisely when an iterated torus knot supports the standard contact structure. This is the first complete UTP...... classification for a large class of knots. We also show that all iterated torus knots that fail the UTP support cabling knot types that are transversely non-simple....
Modeling of chromosome intermingling by partially overlapping uniform random polygons.
Blackstone, T; Scharein, R; Borgo, B; Varela, R; Diao, Y; Arsuaga, J
2011-03-01
During the early phase of the cell cycle the eukaryotic genome is organized into chromosome territories. The geometry of the interface between any two chromosomes remains a matter of debate and may have important functional consequences. The Interchromosomal Network model (introduced by Branco and Pombo) proposes that territories intermingle along their periphery. In order to partially quantify this concept we here investigate the probability that two chromosomes form an unsplittable link. We use the uniform random polygon as a crude model for chromosome territories and we model the interchromosomal network as the common spatial region of two overlapping uniform random polygons. This simple model allows us to derive some rigorous mathematical results as well as to perform computer simulations easily. We find that the probability that one uniform random polygon of length n that partially overlaps a fixed polygon is bounded below by 1 − O(1/√n). We use numerical simulations to estimate the dependence of the linking probability of two uniform random polygons (of lengths n and m, respectively) on the amount of overlapping. The degree of overlapping is parametrized by a parameter [Formula: see text] such that [Formula: see text] indicates no overlapping and [Formula: see text] indicates total overlapping. We propose that this dependence relation may be modeled as f (ε, m, n) = [Formula: see text]. Numerical evidence shows that this model works well when [Formula: see text] is relatively large (ε ≥ 0.5). We then use these results to model the data published by Branco and Pombo and observe that for the amount of overlapping observed experimentally the URPs have a non-zero probability of forming an unsplittable link.
Depreciation Accounting in the Uniform Chart of Accounts.
1982-12-01
footage of building occupied. Reason( s ) for Compute full cost of Rate setting, cash accounting for patient care flow generation and fund- depreciation ing... Horngren , Charles T., Cost Accounting ; A Managerial Emphasis, Prentice-Hall Inc., 1972. 32. Sawyer, Lawrence B., The Practice of Modern Internal Auditing...Awd ubtlft) S . TYPE or RE PORT a PE*IoO CovIERWO Master’s Thesis; Depreciation Accounting in the Uniform Dembr18 Chart of Accounts .PSOiwON.EORlumm
Gaussian quadrature rules for C 1 quintic splines with uniform knot vectors
Barton, Michael; Ait-Haddou, Rachid; Calo, Victor Manuel
2017-01-01
We provide explicit quadrature rules for spaces of C1C1 quintic splines with uniform knot sequences over finite domains. The quadrature nodes and weights are derived via an explicit recursion that avoids numerical solvers. Each rule is optimal, that is, requires the minimal number of nodes, for a given function space. For each of nn subintervals, generically, only two nodes are required which reduces the evaluation cost by 2/32/3 when compared to the classical Gaussian quadrature for polynomials over each knot span. Numerical experiments show fast convergence, as nn grows, to the “two-third” quadrature rule of Hughes et al. (2010) for infinite domains.
Gaussian quadrature rules for C 1 quintic splines with uniform knot vectors
Bartoň, Michael
2017-03-21
We provide explicit quadrature rules for spaces of C1C1 quintic splines with uniform knot sequences over finite domains. The quadrature nodes and weights are derived via an explicit recursion that avoids numerical solvers. Each rule is optimal, that is, requires the minimal number of nodes, for a given function space. For each of nn subintervals, generically, only two nodes are required which reduces the evaluation cost by 2/32/3 when compared to the classical Gaussian quadrature for polynomials over each knot span. Numerical experiments show fast convergence, as nn grows, to the “two-third” quadrature rule of Hughes et al. (2010) for infinite domains.
International Nuclear Information System (INIS)
Boux, R.
1976-01-01
A monitoring device transparent to ionizing radiation, designed to measure the orientation, intensity and uniformity of an incident beam, comprises a cylindrical housing forming at least one ionization chamber with one or more ion-collecting electrodes transverse to the housing axis, each electrode being subdivided into a plurality of mutually insulated conductive elements connected to respective amplifiers. The elements of at least one electrode include one or more outer elements surrounding or bracketing one or more inner elements to measure the radiation in a central zone and a peripheral zone. The outputs of the respective amplifiers are additively and subtractively combined in an evaluation circuit
The reliability of multistory buildings with the effect of non-uniform settlements of foundation
Al'Malul, Rafik; Gadzhuntsev, Michail
2018-03-01
The issue is the evaluation of reliability of construction considering the influence of the variation of the support settlement, which is changing during the lifetime of constructions due to the consolidation process of the ground. Recently, the specialists give special emphasis to the necessity to develop the methods for the estimation of reliability and durability of structures. The problem, the article considers, is the determination of the reliability of multistory buildings with non-uniform changing-in-time sediments caused by the consolidation process in soils. Failure of structures may occur before the draft reaches it`s stabilizing value, because of the violations of the conditions of normal use.
Development of uniform hazard response spectra for Kalpakkam, Kaiga and Kudankulam
International Nuclear Information System (INIS)
Ghosh, A.K.; Rao, K.S.
2009-11-01
Variation of Peak Ground Acceleration (PGA) with mean recurrence interval (MRI) has also been presented using various well-known correlations. The present work develops uniform hazard response spectra i.e. spectra having the same MRI at all frequencies for Kalpakkam, Kaiga and Kudankulam sites. These results determine the seismic hazard at the given site and the associated uncertainties. Typical examples are given to show the sensitivity of the results to changes in various parameters. The results will be useful in evaluation of seismic risk. (author)
Printing system perceptual-based gloss and gloss uniformity standard (INCITS W1.1)
Ng, Yee S.; Cui, Luke C.; Kuo, Chung-Hui; Maggard, Eric; Mashtare, Dale; Morris, Peter; Viola, Michael
2003-12-01
To address the standarization issues of perceptually based image quality for printing systems, ISO/IEC JTC1/SC28, the standarization committee for office equipment charactered the W1.1 project with the responsibiltiy of drafting a proposal for an international standard for the evaluation of printed image quality. One of the W1.1 task teams is charactered to address the issue of 'Gloss and Gloss Uniformity". This paper summarizes the current status and technical progress of this ad hoc team in 2003.
Uniformity of cylindrical imploding underwater shockwaves at very small radii
Yanuka, D.; Rososhek, A.; Bland, S. N.; Krasik, Ya. E.
2017-11-01
We compare the convergent shockwaves generated from underwater, cylindrical arrays of copper wire exploded by multiple kilo-ampere current pulses on nanosecond and microsecond scales. In both cases, the pulsed power devices used for the experiments had the same stored energy (˜500 J) and the wire mass was adjusted to optimize energy transfer to the shockwave. Laser backlit framing images of the shock front were achieved down to the radius of 30 μm. It was found that even in the case of initial azimuthal non-symmetry, the shock wave self-repairs in the final stages of its motion, leading to a highly uniform implosion. In both these and previous experiments, interference fringes have been observed in streak and framing images as the shockwave approached the axis. We have been able to accurately model the origin of the fringes, which is due to the propagation of the laser beam diffracting off the uniform converging shock front. The dynamics of the shockwave and its uniformity at small radii indicate that even with only 500 J stored energies, this technique should produce pressures above 1010 Pa on the axis, with temperatures and densities ideal for warm dense matter research.
Evidence for large-scale uniformity of physical laws
International Nuclear Information System (INIS)
Tubbs, A.D.; Wolfe, A.M.
1980-01-01
The coincidence of redshifts deduced from 21 cm and resonance transitions in absorbing gas detected in front of four quasi-stellar objects results in stringent limits on the variation of the product of three physical constants both in space and in time. We find that α 2 g/sub p/(m/M) is spatially uniform, to a few parts in 10 4 , throughout the observable universe. This uniformity holds subsequent to an epoch corresponding to less than 5% of the current age of the universe t 0 . Moreover, time variations in α 2 g/sub p/m/M are excluded to the same accuracy subsequent to an epoch corresponding to > or approx. =0.20 t 0 . These limits are largely model independent, relying only upon the cosmoligical interpretation of redshifts, and the isotropy of the 3 K background radiation. That a quantity as complex as g/sub p/, which depends on all the details of strong interaction physics, is uniform throughout most of spacetime, even in causally disjoint regions, suggests that all physical laws are globally invariant
Automatic control system for uniformly paving iron ore pellets
Wang, Bowen; Qian, Xiaolong
2014-05-01
In iron and steelmaking industry, iron ore pellet qualities are crucial to end-product properties, manufacturing costs and waste emissions. Uniform pellet pavements on the grate machine are a fundamental prerequisite to ensure even heat-transfer and pellet induration successively influences performance of the following metallurgical processes. This article presents an automatic control system for uniformly paving green pellets on the grate, via a mechanism mainly constituted of a mechanical linkage, a swinging belt, a conveyance belt and a grate. Mechanism analysis illustrates that uniform pellet pavements demand the frontend of the swinging belt oscillate at a constant angular velocity. Subsequently, kinetic models are formulated to relate oscillatory movements of the swinging belt's frontend to rotations of a crank link driven by a motor. On basis of kinetic analysis of the pellet feeding mechanism, a cubic B-spline model is built for numerically computing discrete frequencies to be modulated during a motor rotation. Subsequently, the pellet feeding control system is presented in terms of compositional hardware and software components, and their functional relationships. Finally, pellet feeding experiments are carried out to demonstrate that the control system is effective, reliable and superior to conventional methods.
Divergence from, and Convergence to, Uniformity of Probability Density Quantiles
Directory of Open Access Journals (Sweden)
Robert G. Staudte
2018-04-01
Full Text Available We demonstrate that questions of convergence and divergence regarding shapes of distributions can be carried out in a location- and scale-free environment. This environment is the class of probability density quantiles (pdQs, obtained by normalizing the composition of the density with the associated quantile function. It has earlier been shown that the pdQ is representative of a location-scale family and carries essential information regarding shape and tail behavior of the family. The class of pdQs are densities of continuous distributions with common domain, the unit interval, facilitating metric and semi-metric comparisons. The Kullback–Leibler divergences from uniformity of these pdQs are mapped to illustrate their relative positions with respect to uniformity. To gain more insight into the information that is conserved under the pdQ mapping, we repeatedly apply the pdQ mapping and find that further applications of it are quite generally entropy increasing so convergence to the uniform distribution is investigated. New fixed point theorems are established with elementary probabilistic arguments and illustrated by examples.
The need for a uniform European environmental health database
International Nuclear Information System (INIS)
Stern, Richard M.; Tarkowski, Stanislaw
1989-01-01
Data on which to base the setting of priorities for implementing strategies to reduce public health risks must be of sufficient quality to justify semiquantitative risk assessment. Clusters of negative health outcomes have traditionally alerted authorities at local or national levels to the potential need for regulating suspected environmental hazards, although most initial observations neither reach statistical significance nor uniquely identify putative insults. Four classes of risk factors (environmental and occupational exposures, lifestyle, individual susceptibility, and access to and quality of primary health care) may each account for approximately one quarter of the observed variations in death from the most common causes (e.g. heart and cerebrovascular disease, cancer, and accidents). Preliminary evidence within Europe shows that local mortality from these and other causes can vary by a factor of 2 to 6 regardless of the scale of the region examined, strongly implying a fractile-like structure to the non-uniformity of possibly random health data. This suggests that efforts to identify causes of variations in health outcome cannot be successful without a region-wide, reasonably uniform data set of health outcomes and potential risk factors. Several alternative strategies for establishing a Uniform European Environmental Health Database are considered, together with possible mechanisms for providing basic information for the management of suspected environmental health hazards and quantified health risks. (author)
A simple uniformity test for ultrasound phased arrays.
Dudley, Nicholas J; Woolley, Darren J
2016-09-01
It is difficult to test phased array ultrasound transducers for non functioning elements. We aimed to modify a widely performed test to improve its ease and effectiveness for these arrays. A paperclip was slowly moved along the transducer array, with the scanner operating in M-mode, imaging at a fundamental frequency with automatic gain and grey scale adjustment disabled. Non-functioning elements are identified by a dark vertical line in the image. The test was repeated several times for each transducer, looking for consistency of results. 2 transducers, with faults already shown by electronic transducer testing, were used to validate the method. 23 transducers in clinical use were tested. The results of the modified test on the 2 faulty transducers agreed closely with electronic transducer testing results. The test indicated faults in 5 of the 23 transducers in clinical use: 3 with a single failed element and 2 with non-uniform sensitivity. 1 transducer with non-uniform sensitivity had undergone lens repair; the new lens was visibly non-uniform in thickness and further testing showed a reduction in depth of penetration and a loss of elevational focus in comparison with a new transducer. The modified test is capable of detecting non-functioning elements. Further work is required to provide a better understanding of more subtle faults. Copyright © 2016 Associazione Italiana di Fisica Medica. All rights reserved.
Methods for obtaining a uniform volume concentration of implanted ions
International Nuclear Information System (INIS)
Reutov, V.F.
1995-01-01
Three simple practical methods of irradiations with high energy particles providing the conditions for obtaining a uniform volume concentration of the implanted ions in the massive samples are described in the present paper. Realization of the condition of two-sided irradiation of a plane sample during its rotation in the flux of the projectiles is the basis of the first method. The use of free air as a filter with varying absorbent ability due to movement of the irradiated sample along ion beam brought to the atmosphere is at the basis of the second method of uniform ion alloying. The third method for obtaining a uniform volume concentration of the implanted ions in a massive sample consists of irradiation of a sample through the absorbent filter in the shape of a foil curved according to the parabolic law moving along its surface. The first method is the most effective for obtaining a great number of the samples, for example, for mechanical tests, the second one - for irradiation in different gaseous media, and the third one - for obtaining high concentrations of the implanted ions under controlled (regulated) thermal and deformation conditions. 2 refs., 7 figs
Development of the systems for uniform target irradiation
International Nuclear Information System (INIS)
Voronin, A.Yu.; Garanin, S.G.; Derkach, V.N.; Zhidkov, N.V.; Kravchenko, A.G.; Petrazhitskaya, N.A.; Starodubtsev, K.V.; Sukharev, S.A.; Shnyagin, R.A.
2010-01-01
Complete text of publication follows. The new devices have been developed for laser beams homogenizing in the focal spot - multi-component lens raster and raster with the edges smoothing phase mask. The envelope non-uniformity of -4 radians. Investigation into the temporary-spatial smoothing with the use of low-density foams with the density less than the critical one is still in progress. Experiments on the foams with the density of 1-2.3 mg/cm 3 , thickness of 100-200 μm, and the cells' sizes up to the tens of micrometers were carried out with the radiation wavelength of 0.657 μm. The RMS non-uniformity < 5% has been found for the beam passed through the foam. The non-uniformity is evenly distributed over the spatial frequency spectrum. The induced divergence of radiation is measured to be 0.35 radian. The frequency of the rearranged speckled field of about 2 THz was obtained. The beam smoothing was recorded from the start of pulse of radiation, had the duration up to 1 ns, and the width of the radiation spectrum was about 30 A. The work was performed in part under the sponsorship of the RFFI (grants No. 09-02-12157-ofi-m and No. 09-02-97095-r-povolzh'ye-a) and grant of the President of the RF to leading scientific schools No. 65192.2010.2.
Lukášová, Ivana; Muselík, Jan; Franc, Aleš; Goněc, Roman; Mika, Filip; Vetchý, David
2017-11-15
Warfarin is intensively discussed drug with narrow therapeutic range. There have been cases of bleeding attributed to varying content or altered quality of the active substance. Factor analysis is useful for finding suitable technological parameters leading to high content uniformity of tablets containing low amount of active substance. The composition of tabletting blend and technological procedure were set with respect to factor analysis of previously published results. The correctness of set parameters was checked by manufacturing and evaluation of tablets containing 1-10mg of warfarin sodium. The robustness of suggested technology was checked by using "worst case scenario" and statistical evaluation of European Pharmacopoeia (EP) content uniformity limits with respect to Bergum division and process capability index (Cpk). To evaluate the quality of active substance and tablets, dissolution method was developed (water; EP apparatus II; 25rpm), allowing for statistical comparison of dissolution profiles. Obtained results prove the suitability of factor analysis to optimize the composition with respect to batches manufactured previously and thus the use of metaanalysis under industrial conditions is feasible. Copyright © 2017 Elsevier B.V. All rights reserved.
Long-term dimensional stability and longitudinal uniformity of line scales made of glass ceramics
International Nuclear Information System (INIS)
Takahashi, Akira
2010-01-01
Line scales are commonly used as a working standard of length for the calibration of optical measuring instruments such as profile projectors, measuring microscopes and video measuring systems. For high-precision calibration, line scales with low thermal expansion are commonly used. Glass ceramics have a very low coefficient of thermal expansion (CTE) and are widely used for precision line scales. From a previous study, it is known that glass ceramics decrease in length from the time of production or heat treatment. The line scale measurement method can evaluate more than one section of the line scale and is capable of the evaluation of the longitudinal uniformity of the secular change of glass ceramics. In this paper, an arithmetic model of the secular change of a line scale and its longitudinal uniformity is proposed. Six line scales made of Zerodur®, Clearceram® and synthetic quartz were manufactured at the same time. The dimensional changes of the six line scales were experimentally evaluated over 2 years using a line scale calibration system
Study of the distribution of maxima and minima in multiple sequential images of uniformity
International Nuclear Information System (INIS)
Llacer Martos, S.; Puchal Ane, R.
2011-01-01
To characterize the uniformity of a gamma camera extrinsic used integral uniformity coefficient is calculated with the value of two pixels, the maximum and minimum, single source acquisition of a flat and uniform. This method does not take into account the fact that if a gamma camera having a uniform response, the distribution of these items should be random. In this paper we study how these points are distributed in a succession of large numbers of uniform images.
International Nuclear Information System (INIS)
Xia, Huanxiong; Xiang, Dong; Yang, Wang; Mou, Peng
2014-01-01
Low-temperature plasma technique is one of the critical techniques in IC manufacturing process, such as etching and thin-film deposition, and the uniformity greatly impacts the process quality, so the design for the plasma uniformity control is very important but difficult. It is hard to finely and flexibly regulate the spatial distribution of the plasma in the chamber via controlling the discharge parameters or modifying the structure in zero-dimensional space, and it just can adjust the overall level of the process factors. In the view of this problem, a segmented non-uniform dielectric module design solution is proposed for the regulation of the plasma profile in a CCP chamber. The solution achieves refined and flexible regulation of the plasma profile in the radial direction via configuring the relative permittivity and the width of each segment. In order to solve this design problem, a novel simulation-based auto-design approach is proposed, which can automatically design the positional sequence with multi independent variables to make the output target profile in the parameterized simulation model approximate the one that users preset. This approach employs an idea of quasi-closed-loop control system, and works in an iterative mode. It starts from initial values of the design variable sequences, and predicts better sequences via the feedback of the profile error between the output target profile and the expected one. It never stops until the profile error is narrowed in the preset tolerance
Uniform versus asymmetric shading mediates crown recession in conifers.
Directory of Open Access Journals (Sweden)
Amanda L Schoonmaker
Full Text Available In this study we explore the impact of asymmetrical vs. uniform crown shading on the mortality and growth of upper and lower branches within tree crowns, for two conifer species: shade intolerant lodgepole pine (Pinus contorta and shade tolerant white spruce (Picea glauca. We also explore xylem hydraulics, foliar nutrition, and carbohydrate status as drivers for growth and expansion of the lower and upper branches in various types of shading. This study was conducted over a two-year period across 10 regenerating forest sites dominated by lodgepole pine and white spruce, in the lower foothills of Alberta, Canada. Trees were assigned to one of four shading treatments: (1, complete uniform shading of the entire tree, (2 light asymmetric shading where the lower 1/4-1/3 of the tree crown was shaded, (3 heavy asymmetric shading as in (2 except with greater light reduction and (4 control in which no artificial shading occurred and most of the entire crown was exposed to full light. Asymmetrical shading of only the lower crown had a larger negative impact on the bud expansion and growth than did uniform shading, and the effect was stronger in pine relative to spruce. In addition, lower branches in pine also had lower carbon reserves, and reduced xylem-area specific conductivity compared to spruce. For both species, but particularly the pine, the needles of lower branches tended to store less C than upper branches in the asymmetric shade, which could suggest a movement of reserves away from the lower branches. The implications of these findings correspond with the inherent shade tolerance and self-pruning behavior of these conifers and supports a carbon based mechanism for branch mortality--mediated by an asymmetry in light exposure of the crown.
A practical technique for the generation of highly uniform LIPSS
Energy Technology Data Exchange (ETDEWEB)
Ardron, Marcus, E-mail: ma745@hw.ac.uk [School of Engineering and Physical Sciences, Heriot Watt University, Edinburgh EH14 4AS (United Kingdom); Renishaw PLC, Research Avenue North, Riccarton, Edinburgh EH14 4AP (United Kingdom); Weston, Nick [Renishaw PLC, Research Avenue North, Riccarton, Edinburgh EH14 4AP (United Kingdom); Hand, Duncan [School of Engineering and Physical Sciences, Heriot Watt University, Edinburgh EH14 4AS (United Kingdom)
2014-09-15
Highlights: • Formation of uniform LIPSS on stainless steel is greatly aided by polishing in an orthogonal direction to the expected periodic features. Roughness of a sample surface must avoid vector spatial frequency content near to that of the expected LIPSS. • A very simple polishing technique was found to be suitable. • Surface finish requirement was predicted based on the efficacy factor theory; one of the few theories to give qualitatively strong agreement with experimental evidence in a field that is not fully explained by current theories. • Modelled and experimental results presented. • Using a line focused beam from an ultrafast laser facilitated the rapid production of relatively large areas of LIPSS with a modest laser repetition rate. - Abstract: Laser-induced periodic surface structures (LIPSS) can be reliably produced with ultrashort (<10 ps) laser pulses given fluence near the ablation threshold. Neat, parallel, uniform structures are harder to reproduce. Electrodynamic models show a field at normal incidence interacts with the surface resulting in periodicity in intensity along the surface in the direction of the incident E-field producing ridges and toughs on the surface orthogonal to the E-field. A completely smooth surface offers nothing to perturb the eventual periodic feature formation but is very difficult to achieve: we have demonstrated that simply avoiding surface roughness components near the frequency and direction of the emergent features significantly improves uniform feature production. An appropriate unidirectional polishing process can be realised using an inexpensive spinning cloth wheel. By using a cylindrical lens we were also able to process stainless steel surfaces at 5 mm{sup 2} s{sup −1} so indicating useful industrial potential.
Restoration of non-uniform exposure motion blurred image
Luo, Yuanhong; Xu, Tingfa; Wang, Ningming; Liu, Feng
2014-11-01
Restoring motion-blurred image is the key technologies in the opto-electronic detection system. The imaging sensors such as CCD and infrared imaging sensor, which are mounted on the motion platforms, quickly move together with the platforms of high speed. As a result, the images become blur. The image degradation will cause great trouble for the succeeding jobs such as objects detection, target recognition and tracking. So the motion-blurred images must be restoration before detecting motion targets in the subsequent images. On the demand of the real weapon task, in order to deal with targets in the complex background, this dissertation uses the new theories in the field of image processing and computer vision to research the new technology of motion deblurring and motion detection. The principle content is as follows: 1) When the prior knowledge about degradation function is unknown, the uniform motion blurred images are restored. At first, the blur parameters, including the motion blur extent and direction of PSF(point spread function), are estimated individually in domain of logarithmic frequency. The direction of PSF is calculated by extracting the central light line of the spectrum, and the extent is computed by minimizing the correction between the fourier spectrum of the blurred image and a detecting function. Moreover, in order to remove the strip in the deblurred image, windows technique is employed in the algorithm, which makes the deblurred image clear. 2) According to the principle of infrared image non-uniform exposure, a new restoration model for infrared blurred images is developed. The fitting of infrared image non-uniform exposure curve is performed by experiment data. The blurred images are restored by the fitting curve.
IOOS Data Portals and Uniform On-line Browse Capabilities
Howard, M.; Currier, R. D.; Kobara, S.; Gayanilo, F.
2015-12-01
The Gulf of Mexico Coastal Ocean Observing System Regional Association (GCOOS-RA) is one of eleven Regional Associations organized under the NOAA-led U.S. Integrated Ocean Observing System (IOOS) Program Office. Each of the RAs operate standards-based regional data portals designed to aggregate near real-time and historical observed data and modeled outputs from distributed providers and to offer these and derived products in standardized ways to a diverse set of users. The RA's portals are based on the IOOS Data and Communications Plan which describes the functional elements needed for an interoperable system. One of these elements is called "Uniform On-line Browse" which is an informational service designed primarily to visualize the inventory of a portal. An on-line browse service supports the end user's need to discover what parameters are available, to learn the spatial and temporal extend of the holdings, and to examine the character of the data (e.g, variability, gappiness, etc). These pieces of information help the end user decide if the data are fit for his/her purpose and to construct valid data requests. Note that on-line browse is a distinctly different activity than data analysis because it seeks to yield knowledge about the inventory and not about what the data mean. "Uniform" on-line browse is a service that takes advantage of the standardization of the data portal's data access points. Most portals represent station locations on a map. This is a view of the data inventory but these plots are rarely generated by pulling data through the standards-based services offered to the end users but through methods only available to the portal programmers. This work will present results of Uniform On-line browse tools developed within GCOOS-RA and their applicability to other RA portals.
A practical technique for the generation of highly uniform LIPSS
International Nuclear Information System (INIS)
Ardron, Marcus; Weston, Nick; Hand, Duncan
2014-01-01
Highlights: • Formation of uniform LIPSS on stainless steel is greatly aided by polishing in an orthogonal direction to the expected periodic features. Roughness of a sample surface must avoid vector spatial frequency content near to that of the expected LIPSS. • A very simple polishing technique was found to be suitable. • Surface finish requirement was predicted based on the efficacy factor theory; one of the few theories to give qualitatively strong agreement with experimental evidence in a field that is not fully explained by current theories. • Modelled and experimental results presented. • Using a line focused beam from an ultrafast laser facilitated the rapid production of relatively large areas of LIPSS with a modest laser repetition rate. - Abstract: Laser-induced periodic surface structures (LIPSS) can be reliably produced with ultrashort (<10 ps) laser pulses given fluence near the ablation threshold. Neat, parallel, uniform structures are harder to reproduce. Electrodynamic models show a field at normal incidence interacts with the surface resulting in periodicity in intensity along the surface in the direction of the incident E-field producing ridges and toughs on the surface orthogonal to the E-field. A completely smooth surface offers nothing to perturb the eventual periodic feature formation but is very difficult to achieve: we have demonstrated that simply avoiding surface roughness components near the frequency and direction of the emergent features significantly improves uniform feature production. An appropriate unidirectional polishing process can be realised using an inexpensive spinning cloth wheel. By using a cylindrical lens we were also able to process stainless steel surfaces at 5 mm 2 s −1 so indicating useful industrial potential
The demagnetizing field of a non-uniform rectangular prism
DEFF Research Database (Denmark)
Smith, Anders; Nielsen, Kaspar Kirstein; Christensen, Dennis
2010-01-01
The effect of demagnetization on the magnetic properties of a rectangular ferromagnetic prism under non-uniform conditions is investigated. A numerical model for solving the spatially varying internal magnetic field is developed, validated and applied to relevant cases. The demagnetizing field...... is solved by an analytical calculation and the coupling between applied field, the demagnetization tensor field and spatially varying temperature is solved through iteration. We show that the demagnetizing field is of great importance in many cases and that it is necessary to take into account the non...
Uniform sparse bounds for discrete quadratic phase Hilbert transforms
Kesler, Robert; Arias, Darío Mena
2017-09-01
For each α \\in T consider the discrete quadratic phase Hilbert transform acting on finitely supported functions f : Z → C according to H^{α }f(n):= \\sum _{m ≠ 0} e^{iα m^2} f(n - m)/m. We prove that, uniformly in α \\in T , there is a sparse bound for the bilinear form for every pair of finitely supported functions f,g : Z→ C . The sparse bound implies several mapping properties such as weighted inequalities in an intersection of Muckenhoupt and reverse Hölder classes.
On uniform resampling and gaze analysis of bidirectional texture functions
Czech Academy of Sciences Publication Activity Database
Filip, Jiří; Chantler, M.J.; Haindl, Michal
2009-01-01
Roč. 6, č. 3 (2009), s. 1-15 ISSN 1544-3558 R&D Projects: GA MŠk 1M0572; GA ČR GA102/08/0593 Grant - others:EC Marie Curie(BE) 41358 Institutional research plan: CEZ:AV0Z10750506 Keywords : BTF * texture * eye tracking Subject RIV: BD - Theory of Information Impact factor: 1.447, year: 2009 http://library.utia.cas.cz/separaty/2009/RO/haindl-on uniform resampling and gaze analysis of bidirectional texture functions.pdf
Flexural torsional buckling of uniformly compressed beam-like structures
Ferretti, M.
2018-02-01
A Timoshenko beam model embedded in a 3D space is introduced for buckling analysis of multi-store buildings, made by rigid floors connected by elastic columns. The beam model is developed via a direct approach, and the constitutive law, accounting for prestress forces, is deduced via a suitable homogenization procedure. The bifurcation analysis for the case of uniformly compressed buildings is then addressed, and numerical results concerning the Timoshenko model are compared with 3D finite element analyses. Finally, some conclusions and perspectives are drawn.
Uniform risk spectra of strong earthquake ground motion: NEQRISK
International Nuclear Information System (INIS)
Lee, V.W.; Trifunac, M.D.
1987-01-01
The concept of uniform risk spectra of Anderson and Trifunac (1977) has been generalized to include (1) more refined description of earthquake source zones, (2) the uncertainties in estimating seismicity parameters a and b in log 10 N = a - bM, (3) to consider uncertainties in estimation of maximum earthquake size in each source zone, and to (4) include the most recent results on empirical scaling of strong motion amplitudes at a site. Examples of using to new NEQRISK program are presented and compared with the corresponding case studies of Anderson and Trifunac (1977). The organization of the computer program NEQRISK is also briefly described
Sagagd method for the beam shaping of uniform illumination
International Nuclear Information System (INIS)
Li Yongping; Chen Dewei; Wang Wei
2002-01-01
The simulated annealing algorithm, the genetic and the gradient descent algorithm are retrospectively and successfully amalgamated to optimal design of pure phase element for uniform beams. The process of this method is divided into three steps, first the energy enhancement of the main lobe, then the process to make the top of the main lobe to be smooth and the fringe to be steep, at last the full optimization beam. After these three steps of optimization, the beam is good enough to be applied to ICF
Bid Regulations in a Multi-unit Uniform Price Auction
DEFF Research Database (Denmark)
Boom, Anette
for larger rms does not guarantee market prices below that cap. A suffciently high bid floor only for smaller firms destroys some or all pure strategy equilibria despite their prices being above the bid floor. With a general bid floor this happens only with considerably higher bid floors.......This paper examines the effect of bid regulations on the range of potential equilibrium prices in a multi-unit uniform price auction with heterogenous bidders. General bid caps destroy equilibria with prices above the bid cap and create new equilibria with prices way below the cap. A cap only...
Price Regulations in a Multi-unit Uniform Price Auction
DEFF Research Database (Denmark)
Boom, Anette
not exceed the price cap whereas a selective bid cap for only the larger firms, does not guarantee this outcome. A sufficiently high bid floor always destroys pure strategy equilibria with equilibrium prices above the marginal costs, no matter whether the floor applies to all or only to relatively small......Inspired by recent regulations in the New York ICAP market we examine the effect of different price regulations on a multi-unit uniform price auction. We investigate a bid cap and a bid foor. Given suffciently high total capacities general bid caps always ensure that the market price does...
A uniform quantitative stiff stability estimate for BDF schemes
Directory of Open Access Journals (Sweden)
Winfried Auzinger
2006-01-01
Full Text Available The concepts of stability regions, \\(A\\- and \\(A(\\alpha\\-stability - albeit based on scalar models - turned out to be essential for the identification of implicit methods suitable for the integration of stiff ODEs. However, for multistep methods, knowledge of the stability region provides no information on the quantitative stability behavior of the scheme. In this paper we fill this gap for the important class of Backward Differentiation Formulas (BDF. Quantitative stability bounds are derived which are uniformly valid in the stability region of the method. Our analysis is based on a study of the separation of the characteristic roots and a special similarity decomposition of the associated companion matrix.
Variational optimization algorithms for uniform matrix product states
Zauner-Stauber, V.; Vanderstraeten, L.; Fishman, M. T.; Verstraete, F.; Haegeman, J.
2018-01-01
We combine the density matrix renormalization group (DMRG) with matrix product state tangent space concepts to construct a variational algorithm for finding ground states of one-dimensional quantum lattices in the thermodynamic limit. A careful comparison of this variational uniform matrix product state algorithm (VUMPS) with infinite density matrix renormalization group (IDMRG) and with infinite time evolving block decimation (ITEBD) reveals substantial gains in convergence speed and precision. We also demonstrate that VUMPS works very efficiently for Hamiltonians with long-range interactions and also for the simulation of two-dimensional models on infinite cylinders. The new algorithm can be conveniently implemented as an extension of an already existing DMRG implementation.
Price Regulations in a Multi-unit Uniform Price Auction
DEFF Research Database (Denmark)
Boom, Anette
Inspired by recent regulations in the New York ICAP market we examine the effect of different price regulations on a multi-unit uniform price auction. We investigate a bid cap and a bid foor. Given suffciently high total capacities general bid caps always ensure that the market price does...... not exceed the price cap whereas a selective bid cap for only the larger firms, does not guarantee this outcome. A sufficiently high bid floor always destroys pure strategy equilibria with equilibrium prices above the marginal costs, no matter whether the floor applies to all or only to relatively small...
Does Blue Uniform Color Enhance Winning Probability in Judo Contests?
Dijkstra, Peter D.; Preenen, Paul T. Y.; van Essen, Hans
2018-01-01
The color of an athlete's uniform may have an effect on psychological functioning and consequently bias the chances of winning contests in sport competition. Several studies reported a winning bias for judo athletes wearing a blue outfit relative to those wearing a white outfit. However, we argue there is no winning bias and that previous studies were confounded and based on small and specific data sets. We tested whether blue biases winning in judo using a very extensive judo data set (45,87...
Energy efficient LED layout optimization for near-uniform illumination
Ali, Ramy E.; Elgala, Hany
2016-09-01
In this paper, we consider the problem of designing energy efficient light emitting diodes (LEDs) layout while satisfying the illumination constraints. Towards this objective, we present a simple approach to the illumination design problem based on the concept of the virtual LED. We formulate a constrained optimization problem for minimizing the power consumption while maintaining a near-uniform illumination throughout the room. By solving the resulting constrained linear program, we obtain the number of required LEDs and the optimal output luminous intensities that achieve the desired illumination constraints.
IDEAL STRUCTURE OF UNIFORM ROE ALGEBRAS OVER SIMPLE CORES
Institute of Scientific and Technical Information of China (English)
CHEN XIAOMAN; WANG QIN
2004-01-01
This paper characterizes ideal structure of the uniform Roe algebra B* (X) over sinple cores X. A necessary and sufficient condition for a principal ideal of B*(X) to be spatial is given and an example of non-spatial ideal of B* (X) is constructed. By establishing an one-one correspondence between the ideals of B* (X) and the ω-filters on X, the maximal ideals of B* (X) are completely described by the corona of the Stone-Cech compactification of X.
On uniform world models with matter and radiation
International Nuclear Information System (INIS)
Wojciulewitsch, E.
1977-01-01
Some properties of a universe containing matter with density and radiation with density have been investigated. The use of a density parameter for matter strongly suggests the use of an analogous parameter for radiation. Both parameters are associated with deceleration and their evolution in time can be calculated. The definition of a radiation density paramater allows for a generalization of the Stabell-Refsdal classification of uniform matter universes to universes containing both matter and radiation. In this paper no interaction between matter and radiation has been assumed. The effect of an interaction will be investigated in a future paper. (Author)
Lackland Air Force Base Phase II Uniform Issue: Baseline Report
2011-05-01
Lectures on uniform wearing and care are given 1-2 ORGANIZATION The remainder of this report includes two...sp ec ts al te ra tio ns A pp ro ve d to U S A F sp ec ? Tr ai ne es p ac k ite m s in d uf fle Y es A ll ite m s in sp ec te d? In ve nt...First alteration Second alteration Third alteration Pe rc en ta ge o f t ro us er s al te re d 0% 10% 20% 30% 40% 50% 60% 70% 80%
Magnet polepiece design for uniform magnetic force on superparamagnetic beads
Fallesen, Todd; Hill, David B.; Steen, Matthew; Macosko, Jed C.; Bonin, Keith; Holzwarth, George
2010-01-01
Here we report construction of a simple electromagnet with novel polepieces which apply a spatially uniform force to superparamagnetic beads in an optical microscope. The wedge-shaped gap was designed to keep ∂Bx∕∂y constant and B large enough to saturate the bead. We achieved fields of 300–600 mT and constant gradients of 67 T∕m over a sample space of 0.5×4 mm2 in the focal plane of the microscope and 0.05 mm along the microscope optic axis. Within this space the maximum force on a 2.8 μm di...
parameters affecting the calibration uniformity and traceability of gamma measuring devices
International Nuclear Information System (INIS)
Youssef, S.K.; Henaish, B.A.
1985-01-01
One of the problems which usually defeats the dosimetric evaluations performed by the health and safety experts is the absence of the reproducibility and accuracy of the used measuring devices systems. Furthermore, the traceability of the dose evaluation done by the users themselves are not achieved. Also the uniformity and homogeneity between the various users dosimeters and that available at specified central organization are not maintained. The present manuscript is scoping to deal with such various problems such as: a) dosimeter accuracy, b) traceability of the various users dosimeters and measuring devices. This paper also suggests a programme for the minimum facilities which are required for operating a central calibration laboratory. the responsibility of that central calibration lab., beside the linking chain between the different users and that calibration lab. are stated and discussed in detail. Furthermore, the authors experiences gained in operating the secondary standards calibration laboratory are also reviewed. 2 fig
Radioactive classification of mixed waste -- The need for uniformity
International Nuclear Information System (INIS)
Koch, J.D.
1995-01-01
In July of 1994, many generators of radioactive and mixed wastes found themselves without a means of disposing of their wastes. This has led these generators to thoroughly search the regulations for guidelines to determine at what level something becomes radioactive. Unfortunately, each regulatory agency, EPA, OSHA, NRC, DOT and DOE have their own requirements such that there are no uniform guidelines to assist in making this determination. Subcontractors to the DOE find themselves further frustrated with each remediation site determining radiation levels and commercial treatment, storage and disposal facilities doing the same. This paper examines the need for the uniform classification of radioactive material. It will review past attempts of regulatory agencies to set minimum levels and the current regulatory climate. The paper will also discuss the experience of Quanterra Environmental Services in dealing with the changes in disposal options due to the closure of low-level radioactive disposal facilities to outside compact states, and the impact of the different regulatory requirements
Uniform access to clinical data in a distributed environment. Radiology
International Nuclear Information System (INIS)
Adelhard, K.; Swoboda, N.; Nissen-Meyer, S.; Reiser, M.
1999-01-01
Purpose: Providing medical reports on wards and ambulatory settings in electronic form can improve the quality of health care delivery. Radiology was chosen as an example to demonstrate how to implement uniform access to clinical data in a hospital. Method: Medical professionals at the university hospital in Munich, Grosshadern, have access to all radiological reports of their patients. Web browsers are used as a front end. A centralized administration of users and patients is in place. Results: Centralized access control and patient selection guarantee uniform access to all applicable data via intranet and controls access rights. The high acceptance of this service is reflected by the high number of 150 requests per day. Discussion: Access to radiological reports within the Grosshadern University Clinics was enabled via web browsers in a short time. The high acceptance of the system also proves its easy use. Integration of the system in a centralized user and patient identification system supports the unified access to clinical data. (orig.) [de
Design of a high field uniformity electromagnet for Penning trap
International Nuclear Information System (INIS)
Itteera, Janvin; Singh, Kumud; Teotia, Vikas; Ukarde, Priti; Malhotra, Sanjay; Taly, Y.K.; Joshi, Manoj; Rao, Pushpa
2013-01-01
An ion trap (Penning trap) facility is being developed at BARC for spectroscopy studies. This requires the design of an iron core electromagnet capable of generating high magnetic fields (∼1.7T) at the centre of an 88 mm long air gap. This electromagnet provides the requisite dipole magnetic field which when superimposed on the electrostatic quadrupoles ensures a stable trapping of ions. To conduct high precision spectroscopy studies, we need to ensure a high degree of magnetic field uniformity ( 3 volume (Trap zone). Various pole shoe profiles were studied and modelled, FEM simulation of the same were conducted to compute the magnetic field intensity and field uniformity. Owing to the large air gap and requirement of high field intensity in the GFR, the exciting coils need to handle high current densities, which require water cooled systems. Double Pan-Cake coil design is selected for powering the magnet. Electrical, thermal and hydraulic designs of the coils are completed and a prototype double pancake coil was fabricated and tested for verifying the electrical and thermal parameter. The spatial field homogeneity is achieved by shimming the pole tip. Temporal stability of magnet requires a highly stable power supply for exciting the coils and its stability class is derived from FEM simulations. This paper discusses the electromagnetic design and development of the penning trap magnet being developed at BARC. (author)
Development of electrochemical supercapacitors with uniform nanoporous silver network
International Nuclear Information System (INIS)
Li, Rui; Liu, Xiongjun; Wang, Hui; Wu, Yuan; Lu, Z.P.
2015-01-01
Metal oxides such as manganese dioxide (MnO 2 ) are often used as electrode materials for supercapacitors due to their high specific capacitance. In practice, however, their specific capacitance is much smaller than the theoretical limit due to the low electrical conductivity and serious agglomeration. In the present work, we demonstrate that highly conductive nanoporous silver (NPS) network with uniform continuous nanoporosity and high surface area which was fabricated by dealloying Ag-Mg-Ca metallic glasses can be employed as supports and collectors for MnO 2 capacitors. By plating the MnO 2 nanocrystals into the nanopore structure, the NPS/MnO 2 composite electrode provides fast ionic conduction and excellent electron-proton transport, resulting in an ultrahigh specific capacitance of the plated active MnO 2 (∼1088 F g −1 ), which is close to the theoretical limit. The unique combination of high specific capacitance and long cycle life enhanced by the current composite structure makes the NPS/MnO 2 composite promising for electrochemical supercapacitor as electrode material. In addition, our findings suggest that the uniform NPS network is capable for improving capacitance performance of metal oxides in electrochemical supercapacitors.
Applying a uniform layer of disinfectant by wiping.
Cooper, D W
2000-01-01
Disinfection or sterilization often requires applying a film of liquid to a surface, frequently done by using a wiper as the applicator. The wiper must not only hold a convenient amount of liquid, it must deposit it readily and uniformly. Contact time is critical to disinfection efficacy. Evaporation can limit the contact time. To lengthen the contact time, thickly applied layers are generally preferred. The thickness of such layers can be determined by using dyes or other tracers, as long as the tracers do not significantly affect the liquid's surface tension and viscosity and thus do not affect the thickness of the applied layer. Alternatively, as done here, the thickness of the layer can be inferred from the weight loss of the wiper. Results are reported of experiments on thickness of the layers applied under various conditions. Near saturation, hydrophilic polyurethane foam wipers gave layers roughly 10 microns thick, somewhat less than expected from hydrodynamic theory, but more than knitted polyester or woven cotton. Wipers with large liquid holding capacity, refilled often, should produce more nearly uniform layers. Higher pressures increase saturation in the wiper, tending to thicken the layer, but higher pressures also force liquid from the interface, tending to thin the layer, so the net result could be thicker or thinner layers, and there is likely to be an optimal pressure.
Radiometric determination of uniformity of putting paraffin on textile threads
International Nuclear Information System (INIS)
Ridel', Z.; Kherrmann, Eh.; Shefer, I.; Tseiner, A.
1979-01-01
To improve processing of the natural and synthetic fiber threads on stocking-frames, they are treated by paraffin. Paraffin is applied in the amounts nearly equal to 0.1 -1.0 g for 10 4 m of the thread's length. To determine amount of paraffin on thread and to determine uniformity if its application, a radiometric method has been developed. As a radioactive label, didocilephosphate of rare earths was used. This compound has good solubility in hydrocarbons and does not change physical properties of paraffin in the investigated field of its application as well as its concentration. It is possible to add to paraffin this radioactive label or a non-active label with subsequent its activation. Amount of paraffin, applied on a thread is determined by means of measurement of activity of thread samples of different length. Information about uniformity of paraffin application on thread have been obtained by means of autoradiography. It has been found that paraffin in mainly applied on the thread's bulges [ru
International Nuclear Information System (INIS)
Cho, Seong-Hoon; Kim, Taeyoung; Kim, Hyun Jae; Park, Kihyun; Roberts, Roland K.
2015-01-01
The objective of our research is to predict how electricity demand varies spatially between status quo regionally-uniform electricity pricing and hypothetical regionally-varying electricity pricing across usage categories. We summarize the empirical results of a case study of electricity demand in South Korea with three key findings and their related implications. First, the price elasticities of electricity demand differ across usage categories. Specifically, electricity demands for manufacturing and retail uses are price inelastic and close to unit elastic, respectively, while those for agricultural and residential uses are not statistically significant. This information is important in designing energy policy, because higher electricity prices could reduce electricity demands for manufacturing and retail uses, resulting in slower growth in those sectors. Second, spatial spillovers in electricity demand vary across uses. Understanding the spatial structure of electricity demand provides useful information to energy policy makers for anticipating changes in demand across regions via regionally-varying electricity pricing for different uses. Third, simulation results suggest that spatial variations among electricity demands by usage category under a regionally-varying electricity-pricing policy differ from those under a regionally-uniform electricity-pricing policy. Differences in spatial changes between the policies provide information for developing a realistic regionally-varying electricity-pricing policy according to usage category. - Highlights: • We compare regionally-varying and regionally-uniform electricity pricing policies. • We summarize empirical results of a case study of electricity demand in South Korea. • We confirm that spatial spillovers in electricity demands vary across different uses. • We find positive spatial spillovers in the manufacturing and residential sectors. • Our methods help policy makers evaluate regionally-varying pricing
Kannojiya, Vikas; Sharma, Riya; Gaur, Rahul; Jangra, Anil; Yadav, Pushpender; Prajapati, Pooja
2018-03-01
The overheating of an industrial component sometimes may leads to system failure. The convection heat transfer from a heated surface can be effectively enhanced by employing fins on that surface. This Paper emphasizes on the experimental investigation of temperature distribution along the length of pin shaped fin. The analysis is performed on a 100 mm long fin made up of brass with 19.6 mm diameter having thermal conductivity as 111 W/m.K. Temperature at different section of the fin along its length is evaluated experimentally and theoretically. The influence of convection mode viz natural & forced convection and variable heat input on the temperature distribution is evaluated. The result outcomes are then compared with the widely accepted analytical relations. A comparison of convective heat transfer coefficient for uniform and non-uniform area fin is also presented. The results by experimental and analytical method are found to be in good agreement for free convection phenomenon.
Synthesis of uniformly labelled organic compounds by polymerization of 14C ethylene
International Nuclear Information System (INIS)
Dauphin, J.-F.
1972-01-01
The synthesis of 14 C uniformly labelled compounds is described. By polymerization of 14 C ethylene, linear olefins with a double bond at α position were obtained. From these olefins, uniformly labelled alkanes, alcohols and acids were prepared [fr
Zhu, Yuying; Wang, Jianmin; Wang, Cunfang
2018-05-01
Taking fresh goat milk as raw material after filtering, centrifuging, hollow fiber ultrafiltration, allocating formula, value detection and preparation processing, a set of 10 goat milk mixed standard substances was prepared on the basis of one-factor-at-a-time using a uniform design method, and its accuracy, uniformity and stability were evaluated by paired t-test and F-test of one-way analysis of variance. The results showed that three milk composition contents of these standard products were independent of each other, and the preparation using the quasi-level design method, and without emulsifier was the best program. Compared with detection value by cow milk standards for calibration fast analyzer, the calibration by goat milk mixed standard was more applicable to rapid detection of goat milk composition, detection value was more accurate and the deviation showed less error. Single factor analysis of variance showed that the uniformity and stability of the mixed standard substance were better; it could be stored for 15 days at 4°C. The uniformity and stability of the in-units and inter-units could meet the requirements of the preparation of national standard products. © 2018 Japanese Society of Animal Science.
El-Amin, Mohamed; Sun, Shuyu
2010-01-01
In most of real-world applications, such as the case of heat stores, inlet is not kept at a constant temperature but it may vary with time during charging process. In this paper, a vertical water jet injected into a rectangular storage tank is measured experimentally and simulated numerically. Two cases of study are considered; one is a hot water jet with uniform inlet temperature (UIT) injected into a cold water tank, and the other is a cold water jet with non-uniform inlet temperature (NUIT) injected into a hot water tank. Three different temperature differences and three different flow rates are studied for the hot water jet with UIT which is injected into a cold water tank. Also, three different initial temperatures with constant flow rate as well as three different flow rates with constant initial temperature are considered for the cold jet with NUIT which is injected into a hot water tank. Turbulence intensity at the inlet as well as Reynolds number for the NUIT cases are therefore functions of inlet temperature and time. Both experimental measurements and numerical calculations are carried out for the same measured flow and thermal conditions. The realizable k-ε model is used for modeling the turbulent flow. Numerical solutions are obtained for unsteady flow while pressure, velocity, temperature and turbulence distributions inside the water tank are analyzed. The simulated results are compared to the measured results, and they show a good agreement at low temperatures. © 2010 IEEE.
Energy Technology Data Exchange (ETDEWEB)
Suphanit, B. [Department of Chemical Engineering, Faculty of Engineering, King Mongkut' s University of Technology Thonburi, Pracha Utit Rd., Tungkru, Bangkok 10140 (Thailand)
2010-03-15
The internally heat-integrated distillation column (HIDiC) is a complex column configuration which is more energy efficient than the equivalent conventional column or the distillation column with direct vapor recompression scheme (VRC). Exploiting the heat integration between two diabatic sections operating at different pressures of the HIDiC can greatly enhance the energy performance of the system. On the other hand, the design and optimization of HIDiC is more difficult than those of the conventional distillation column or the column with VRC. The former involves many design parameters, and the most critical one is the pressure ratio between both diabatic sections. However, the heat distribution along the diabatic sections is also another significant factor not yet thoroughly investigated. In this work, two typical distribution schemes, i.e. uniform heat transfer area and uniform heat distribution, are studied by applying a novel approach to solve the simulation problem in Aspen Plus 2004.1. The comparison of both distributing schemes is discussed via two widely-used case studies, namely benzene-toluene separation and propylene-propane splitter. (author)
El-Amin, Mohamed
2010-12-01
In most of real-world applications, such as the case of heat stores, inlet is not kept at a constant temperature but it may vary with time during charging process. In this paper, a vertical water jet injected into a rectangular storage tank is measured experimentally and simulated numerically. Two cases of study are considered; one is a hot water jet with uniform inlet temperature (UIT) injected into a cold water tank, and the other is a cold water jet with non-uniform inlet temperature (NUIT) injected into a hot water tank. Three different temperature differences and three different flow rates are studied for the hot water jet with UIT which is injected into a cold water tank. Also, three different initial temperatures with constant flow rate as well as three different flow rates with constant initial temperature are considered for the cold jet with NUIT which is injected into a hot water tank. Turbulence intensity at the inlet as well as Reynolds number for the NUIT cases are therefore functions of inlet temperature and time. Both experimental measurements and numerical calculations are carried out for the same measured flow and thermal conditions. The realizable k-ε model is used for modeling the turbulent flow. Numerical solutions are obtained for unsteady flow while pressure, velocity, temperature and turbulence distributions inside the water tank are analyzed. The simulated results are compared to the measured results, and they show a good agreement at low temperatures. © 2010 IEEE.
School Violence and Its Effect on the Constitutionality of Public School Uniform Policies.
Starr, Jennifer
2000-01-01
The Arizona Court of Appeals, in the first court decision regarding public school uniform policies, held that mandatory school uniforms do not violate students' First Amendment rights. Discusses the Arizona decision and its effect on the structuring of school uniform policies and their potential successful institution at the high school level. (31…
What the United Kingdom Can Teach the United States about School Uniforms
Walmsley, Angela
2011-01-01
School uniforms are commonplace in the United Kingdom and seem to help promote students' respect for the teachers, the school, and themselves. Parents like the uniforms because they see it as a less expensive alternative. Teachers say they appreciate school uniforms because they help students focus on school and not each other's clothes. However,…
Wade, Kathleen Kiley; Stafford, Mary E.
2003-01-01
Examined the relationship between public school uniforms and student self-worth and student and staff perceptions of gang presence and school climate. Surveys of middle school students and teachers indicated that although students' perceptions did not vary across uniform policy, teachers from schools with uniform policies perceived lower levels of…
The Relationship of School Uniforms to Student Attendance, Achievement, and Discipline
Sowell, Russell Edward
2012-01-01
This causal-comparative study examined the relationship of school uniforms to attendance, academic achievement, and discipline referral rates, using data collected from two high schools in rural southwest Georgia county school systems, one with a uniforms program and one without a uniforms program. After accounting for race and students with…
Making the School Uniform Decision: Is It Right for "Your" School?
McDaniel, Thomas R.
2013-01-01
Do school uniforms make a difference in student academic performance, school spirit, discipline, and safety? What are the legal restrictions that bear on the school uniform decision in public schools? Do uniform policies lead to less school violence? Do they impose an economic hardship, outweighing the advantages, on low-income families? The…
Uniform sources of ionizing radiation of extended area from radiotoned photographic film
International Nuclear Information System (INIS)
Thackray, M.
1978-01-01
The technique of toning photographic films, that have been uniformly exposed and developed, with radionuclides to provide uniform sources of ionizing radiation of extended area and their uses in radiography are discussed. The suitability of various radionuclides for uniform-plane sources is considered. (U.K.)
49 CFR Appendix A to Part 1035 - Uniform Straight Bill of Lading
2010-10-01
... 49 Transportation 8 2010-10-01 2010-10-01 false Uniform Straight Bill of Lading A Appendix A to Part 1035 Transportation Other Regulations Relating to Transportation (Continued) SURFACE... Appendix A to Part 1035—Uniform Straight Bill of Lading Uniform Straight Bill of Lading Original—Not...
Are School Uniforms a Good Fit? Results from the ECLS-K and the NELS
Yeung, Ryan
2009-01-01
One of the most common proposals put forth for reform of the American system of education is to require school uniforms. Proponents argue that uniforms can make schools safer and also improve school attendance and increase student achievement. Opponents contend that uniforms have not been proven to work and may be an infringement on the freedom of…
Protocol for uniformly measuring and expressing the performance of energy storage systems.
Energy Technology Data Exchange (ETDEWEB)
Ferreira, Summer Kamal Rhodes; Rose, David Martin; Schoenwald, David A; Bray, Kathy; Conover, David; Kintner-Meyer, Michael; Viswanathan, Vilayanur
2013-08-01
The U.S. Department of Energys Energy Storage Systems (ESS) Program, through the support of Pacific Northwest National Laboratory (PNNL) and Sandia National Laboratories (SNL), facilitated the development of the protocol provided in this report. The focus of the protocol is to provide a uniform way of measuring, quantifying, and reporting the performance of ESSs in various applications; something that does not exist today and, as such, is hampering the consideration and use of this technology in the market. The availability of an application-specific protocol for use in measuring and expressing performance-related metrics of ESSs will allow technology developers, power-grid operators and other end-users to evaluate the performance of energy storage technologies on a uniform and comparable basis. This will help differentiate technologies and products for specific application(s) and provide transparency in how performance is measured. It also will assist utilities and other consumers of ESSs to make more informed decisions as they consider the potential application and use of ESSs, as well as form the basis for documentation that might be required to justify utility investment in such technologies.
Protocol for Uniformly Measuring and Expressing the Performance of Energy Storage Systems
Energy Technology Data Exchange (ETDEWEB)
Bray, Kathryn L.; Conover, David R.; Kintner-Meyer, Michael CW; Viswanathan, Vijayganesh; Ferreira, Summer; Rose, David; Schoenwald, David
2012-10-01
The U.S. Department of Energy’s Energy Storage Systems (ESS) Program, through the support of Pacific Northwest National Laboratory (PNNL) and Sandia National Laboratories (SNL), facilitated the development of the protocol provided in this report. The focus of the protocol is to provide a uniform way of measuring, quantifying, and reporting the performance of EESs in various applications; something that does not exist today and, as such, is hampering the consideration and use of this technology in the market. The availability of an application-specific protocol for use in measuring and expressing performance-related metrics of ESSs will allow technology developers, power-grid operators and other end-users to evaluate the performance of energy storage technologies on a uniform and comparable basis. This will help differentiate technologies and products for specific application(s) and provide transparency in how performance is measured. It also will assist utilities and other consumers of ESSs make more informed decisions as they consider the potential application and use of ESSs, as well as form the basis for documentation that might be required to justify utility investment in such technologies.
Ultraporous films with uniform nanochannels by block copolymer micelles assembly
Nunes, Suzana Pereira
2010-10-12
Films with high pore density and regularity that are easy to manufacture by conventional large-scale technology are key components aimed for fabrication of new generations of magnetic arrays for storage media, medical scaffolds, and artificial membranes. However, potential manufacture strategies like the self-assembly of block copolymers, which lead to amazing regular patterns, could be hardly reproduced up to now using commercially feasible methods. Here we report a unique production method of nanoporous films based on the self-assembly of copper(II) ion-polystyrene-b-poly(4-vinylpyridine) complexes and nonsolvent induced phase separation. Extremely high pore densities and uniformity were achieved. Water fluxes of 890 L m-2 h-1 bar-1 were obtained, which are at least 1 order of magnitude higher than those of commercially available membranes with comparable pore size. The pores are also stimuli (pH)-responsive. © 2010 American Chemical Society.
Uniformly accelerating charged particles. A threat to the equivalence principle
International Nuclear Information System (INIS)
Lyle, Stephen N.
2008-01-01
There has been a long debate about whether uniformly accelerated charges should radiate electromagnetic energy and how one should describe their worldline through a flat spacetime, i.e., whether the Lorentz-Dirac equation is right. There are related questions in curved spacetimes, e.g., do different varieties of equivalence principle apply to charged particles, and can a static charge in a static spacetime radiate electromagnetic energy? The problems with the LD equation in flat spacetime are spelt out in some detail here, and its extension to curved spacetime is discussed. Different equivalence principles are compared and some vindicated. The key papers are discussed in detail and many of their conclusions are significantly revised by the present solution. (orig.)
Boundary-induced pattern formation from uniform temporal oscillation
Kohsokabe, Takahiro; Kaneko, Kunihiko
2018-04-01
Pattern dynamics triggered by fixing a boundary is investigated. By considering a reaction-diffusion equation that has a unique spatially uniform and limit cycle attractor under a periodic or Neumann boundary condition, and then by choosing a fixed boundary condition, we found three novel phases depending on the ratio of diffusion constants of activator to inhibitor: transformation of temporally periodic oscillation into a spatially periodic fixed pattern, travelling wave emitted from the boundary, and aperiodic spatiotemporal dynamics. The transformation into a fixed, periodic pattern is analyzed by crossing of local nullclines at each spatial point, shifted by diffusion terms, as is analyzed by using recursive equations, to obtain the spatial pattern as an attractor. The generality of the boundary-induced pattern formation as well as its relevance to biological morphogenesis is discussed.
Effective electrodiffusion equation for non-uniform nanochannels.
Marini Bettolo Marconi, Umberto; Melchionna, Simone; Pagonabarraga, Ignacio
2013-06-28
We derive a one-dimensional formulation of the Planck-Nernst-Poisson equation to describe the dynamics of a symmetric binary electrolyte in channels whose section is nanometric and varies along the axial direction. The approach is in the spirit of the Fick-Jacobs diffusion equation and leads to a system of coupled equations for the partial densities which depends on the charge sitting at the walls in a non-trivial fashion. We consider two kinds of non-uniformities, those due to the spatial variation of charge distribution and those due to the shape variation of the pore and report one- and three-dimensional solutions of the electrokinetic equations.
Illumination uniformity requirements for direct drive inertial confinement fusion
International Nuclear Information System (INIS)
Rothenberg, J.E.; Eimerl, D.; Key, M.H.; Weber, S.V.
1995-01-01
The requirements for laser uniformity are discussed in terms of the ell-mode spectrum. It is shown that the choice of smoothing methods can significantly alter this spectrum and that this choice should be made in the context of the target physics. Although two dimensional smoothing by spectral dispersion yields a high quality near field beam profile, it results in poor smoothing for low spatial frequency. The partially coherent light method (fiber smoothing) leads to superior smoothing at low spatial frequencies, but has very poor near field beam quality. As a result, it may be desirable to use partially coherent light during the driver pulse foot (at low intensity and when minimizing the laser imprint is critical) and smoothing by spectral dispersion during the main pulse
Generalized Landau-Lifshitz-Gilbert equation for uniformly magnetized bodies
Energy Technology Data Exchange (ETDEWEB)
Serpico, C. [Dipartimento di Ingegneria Elettrica, Universita di Napoli ' FedericoII' , Via Claudio 21, I-80125 Naples (Italy)], E-mail: serpico@unina.it; Mayergoyz, I.D. [ECE Department and UMIACS, University of Maryland, College Park, MD 20742 (United States); Bertotti, G. [Istituto Nazionale di Ricerca Metrologica (INRiM), I-10135 Turin (Italy); D' Aquino, M. [Dipartimento per le Tecnologie, University of Napoli ' Parthenope' , I-80133 Naples (Italy); Bonin, R. [Istituto Nazionale di Ricerca Metrologica (INRiM), I-10135 Turin (Italy)
2008-02-01
We consider generalized Landau-Lifshitz-Gilbert (LLG) deterministic dynamics in uniformly magnetized bodies. The dynamics take place on the unit sphere {sigma}, and are characterized by a vector field v tangential to {sigma}. By using Helmholtz decomposition on {sigma}, it is proven that v is uniquely defined by two potentials {chi} and {psi}. Potential {chi} can be identified with the free energy of the system, while {psi} describes non-conservative interactions of the system with the environment. The presence of {psi} modifies the usual energy balance of LLG dynamics. Instead of purely relaxation dynamics we may have steady injection of energy through non-conservative interactions. The implications of the new form of the energy balance are discussed in detail.
The electric field of a uniformly charged cubic shell
McCreery, Kaitlin; Greenside, Henry
2018-01-01
As an integrative and insightful example for undergraduates learning about electrostatics, we discuss how to use symmetry, Coulomb's law, superposition, Gauss's law, and visualization to understand the electric field E (x ,y ,z ) produced by a uniformly charged cubic shell. We first discuss how to deduce qualitatively, using freshman-level physics, the perhaps surprising fact that the interior electric field is nonzero and has a complex structure, pointing inwards from the middle of each face of the shell and pointing outwards towards each edge and corner. We then discuss how to understand the quantitative features of the electric field by plotting an analytical expression for E along symmetry lines and on symmetry surfaces of the shell.
Non-uniform plastic deformation of micron scale objects
DEFF Research Database (Denmark)
Niordson, Christian Frithiof; Hutchinson, J. W.
2003-01-01
Significant increases in apparent flow strength are observed when non-uniform plastic deformation of metals occurs at the scale ranging from roughly one to ten microns. Several basic plane strain problems are analyzed numerically in this paper based on a new formulation of strain gradient...... plasticity. The problems are the tangential and normal loading of a finite rectangular block of material bonded to rigid platens and having traction-free ends, and the normal loading of a half-space by a flat, rigid punch. The solutions illustrate fundamental features of plasticity at the micron scale...... that are not captured by conventional plasticity theory. These include the role of material length parameters in establishing the size dependence of strength and the elevation of resistance to plastic flow resulting from constraint on plastic flow at boundaries. Details of the finite element method employed...
Uniform magnetic excitations in NiO nanoparticles
DEFF Research Database (Denmark)
Bahl, C.R.H.; Kuhn, L.T.; Lefmann, K.
2006-01-01
A sample of isolated disc shaped NiO nanoparticles was studied at the RITA-II triple axis spectrometer at SINQ (PSI) using the newly implemented multi-analyser blade imaging mode. The particles were 13 nm in diameter and had a thickness of about 2.5 nm. A non-dispersive spin excitation was observed...... at the antiferromagnetic ((1)/(2) (1)/(2) (1)/(2)) reflection at a scattering vector of kappa = 1.30 angstrom(-1), at an energy of 2 0.51 +/- 0.02 meV. This is shown to be due to uniform magnetic excitations in the nanoparticles. (c) 2006 Elsevier B.V. All rights reserved....
A Uniform Framework of Global Nuclear Materials Management
International Nuclear Information System (INIS)
Dupree, S.A.; Mangan, D.L.; Sanders, T.L; Sellers, T.A.
1999-01-01
Global Nuclear Materials Management (GNMM) anticipates and supports a growing international recognition of the importance of uniform, effective management of civilian, excess defense, and nuclear weapons materials. We expect thereto be a continuing increase in both the number of international agreements and conventions on safety, security, and transparency of nuclear materials, and the number of U.S.-Russian agreements for the safety, protection, and transparency of weapons and excess defense materials. This inventory of agreements and conventions may soon expand into broad, mandatory, international programs that will include provisions for inspection, verification, and transparency, To meet such demand the community must build on the resources we have, including State agencies, the IAEA and regional organizations. By these measures we will meet the future expectations for monitoring and inspection of materials, maintenance of safety and security, and implementation of transparency measures
Non-Uniform Heat Transfer in Thermal Regenerators
DEFF Research Database (Denmark)
Jensen, Jesper Buch
, a numerical model, which simulates a single-blow operation in a parallel-plate regenerator, was developed and used to model the heat transfer under various conditions. In addition to the modeling of the heat transfer, a series of experiments on passive regenerators with non-uniform, but precisely controlled....... Additionally, the experiments gave real comparative results, whereas the model to a certain degree more served to provide insight to the heat transfer processes taking place inside the regenera- tors, something that would be - if not impossible - then highly impractical to do experimentally. It has been found......This thesis presents investigations on the heat transfer in complex heat ex- changers in general and in regenerative heat exchangers (regenerators) in par- ticular. The motivation for this work is a result of inconsistencies obeserved in the results from a series of experiments on active magnetic...
Refractive index of silica aerogel: Uniformity and dispersion law
International Nuclear Information System (INIS)
Bellunato, T.; Calvi, M.; Matteuzzi, C.; Musy, M.; Perego, D.L.; Storaci, B.
2008-01-01
Two methods for the measurement of the uniformity of the refractive index n within a single block of silica aerogel are described. One is based on the deflection of a laser beam induced by transverse index gradients. The second exploits the Cherenkov effect, measuring the emission angle of photons radiated by 500 MeV electrons traversing the aerogel. The beam can scan the full aerogel surface providing information on point to point variations of n. The measurement of the dispersion law n(λ) is also reported. An Xe lamp coupled to a diffraction grating provides the monochromatic source. The index for each λ is measured by the prism method at a corner of an aerogel sample. A Sellmeier functional form for n(λ) is assumed, and the parameters best fitting the experimental data are given
The Honeycomb illusion: Uniform textures not perceived as such
Directory of Open Access Journals (Sweden)
Marco Bertamini
2016-07-01
Full Text Available We present a series of patterns, in which texture is perceived differently at fixation in comparison to the periphery, such that a physically uniform stimulus yields a nonuniform percept. We call this the Honeycomb illusion, and we discuss it in relation to the similar Extinction illusion (Ninio & Stevens, 2000. The effect remains strong despite multiple fixations, dynamic changes, and manipulations of the size of texture elements. We discuss the phenomenon in relation to how vision achieves a detailed and stable representation of the environment despite changes in retinal spatial resolution and dramatic changes across saccades. The Honeycomb illusion complements previous related observations in suggesting that this representation is not necessarily based on multiple fixations (i.e., memory or on extrapolation from information available to central vision.
Decomposition of macrophytes with uniformly C-14-labelled plant material
International Nuclear Information System (INIS)
Blake, G.
1979-01-01
Uniform labelling of plant such as macrophytes is relatively difficult to obtain. In my experiments I used samples of ripe stems and leaves of labelled maize which had grown for 110 days in a 14 Co 2 atmosphere. These samples were laid in a glass bowl for in situ and in vitro experiments under similar conditions of light and temperature. The aim of this study was to determine the shift of carbon through chosen compartments of a core (water, sediments, bacteria, invertebrates, atmosphere) and to understand the mineralization process with type of particulate organic matter. At low temperature (7 0 C), leaching of organic matter in the first 5 days increases bacteria activity, then radioactivity-incorporation level declines to the 60th day; CO 2 production was measured during experiments and was varying between 60% and 75% of used carbon of the tissue. (orig.) [de
Kleinian groups and uniformization in examples and problems
Krushkal′, S L
1986-01-01
Aimed at researchers, graduate students and undergraduates alike, this book presents a unified exposition of all the main areas and methods of the theory of Kleinian groups and the theory of uniformization of manifolds. The past 20 years have seen a rejuvenation of the field, due to the development of powerful new methods in topology, the theory of functions of several complex variables, and the theory of quasiconformal mappings. Thus this new book should provide a valuable resource, listing the basic facts regarding Kleinian groups and serving as a general guide to the primary literature, particularly the Russian literature in the field. In addition, the book includes a large number of examples, problems, and unsolved problems, many of them presented for the first time.
Uniformity in radiation protection legislation in Australia: a case study
International Nuclear Information System (INIS)
Robotham, F.P.J.
2003-01-01
This paper describes a recent licensing/approval process conducted by a company that has three plants utilizing large sealed sources of Cobalt-60, in one case approximately 70PBq. The company has operated successfully in one Australian State since 1971 and in a second since 1985. By 1999 it became apparent that there was sufficient business to warrant the opening of a third plant in a third Australian State. The plant chosen has a design capacity of 185PBq and an initial loading of 1 IPBq. This paper describes some of the licensing process and demonstrates, I believe, the urgent need for both uniformity in Australian Radiation Safety Legislation and consistency in interpretation and implementation. Copyright (2003) Australasian Radiation Protection Society Inc
Examination of uniform momentum zones in hypersonic turbulent boundary layers
Williams, Owen; Helm, Clara; Martin, Pino
2017-11-01
The presence of uniform momentum zones (UMZs) separated by regions of high shear is now well-established in incompressible flows, with the mean number of such zones increasing in a log-linear fashion with Reynolds number. While known to be present in supersonic and hypersonic boundary layers, the properties of these UMZs and the appropriate Reynolds number for comparison with incompressible results have not previously been investigated. A large, previously published DNS database of hypersonic boundary layers is used in this investigation, with Mach numbers up to 12 and wall temperatures from cold to adiabatic, resulting in a wide range of outer layer Reynolds numbers. UMZs are examined using a range of parameters in both conventional inner and semi-local scalings, and Reynolds number trends examined.
Uniform magnetic fields in density-functional theory
Tellgren, Erik I.; Laestadius, Andre; Helgaker, Trygve; Kvaal, Simen; Teale, Andrew M.
2018-01-01
We construct a density-functional formalism adapted to uniform external magnetic fields that is intermediate between conventional density functional theory and Current-Density Functional Theory (CDFT). In the intermediate theory, which we term linear vector potential-DFT (LDFT), the basic variables are the density, the canonical momentum, and the paramagnetic contribution to the magnetic moment. Both a constrained-search formulation and a convex formulation in terms of Legendre-Fenchel transformations are constructed. Many theoretical issues in CDFT find simplified analogs in LDFT. We prove results concerning N-representability, Hohenberg-Kohn-like mappings, existence of minimizers in the constrained-search expression, and a restricted analog to gauge invariance. The issue of additivity of the energy over non-interacting subsystems, which is qualitatively different in LDFT and CDFT, is also discussed.
Prediction of incipient flow boiling from a uniformly heated surface
International Nuclear Information System (INIS)
Yin, S.T.; Abdelmessih, A.H.
1977-01-01
This study was undertaken to investigate the phenomenon of liquid superheat during incipient boiling in a uniformly heated forced convection channel. Experimental data were obtained using Freon 11 as the test medium. Based on existing theories, an analytical method was developed for predicting the point of termination of nucleate boiling, observed during a decreasing heat flux process with a nucleation activated surface. The method may also be used to predict the point of boiling incipience, observed during an increasing heat flux process with a non-activated surface; this point does not appear to have been treated analytically in previous work. It can be shown that some of the existing models are special cases of the present formulation
A Uniform Framework of Global Nuclear Materials Management
Energy Technology Data Exchange (ETDEWEB)
Dupree, S.A.; Mangan, D.L.; Sanders, T.L; Sellers, T.A.
1999-04-20
Global Nuclear Materials Management (GNMM) anticipates and supports a growing international recognition of the importance of uniform, effective management of civilian, excess defense, and nuclear weapons materials. We expect thereto be a continuing increase in both the number of international agreements and conventions on safety, security, and transparency of nuclear materials, and the number of U.S.-Russian agreements for the safety, protection, and transparency of weapons and excess defense materials. This inventory of agreements and conventions may soon expand into broad, mandatory, international programs that will include provisions for inspection, verification, and transparency, To meet such demand the community must build on the resources we have, including State agencies, the IAEA and regional organizations. By these measures we will meet the future expectations for monitoring and inspection of materials, maintenance of safety and security, and implementation of transparency measures.
Expedited, uniform processing of multi-vendor gamma test data
International Nuclear Information System (INIS)
Zimmerman, R.E.
2002-01-01
Aim: Acceptance testing of gamma camera performance is time consuming. When data is collected from different vendors image format and methodology differences can result in disjointed and difficult to compare results. Even when performing NEMA specified tests consistent processing of data from multi-vendor cameras results in methodological inconsistencies. A more uniform and consistent method to process data collected from gamma cameras would be a boon to those involved in acquiring and processing such test data. Methods and Materials: Image J is an image processing program freely available on the Web at http://rsb.info.nih.gov/ij/. It can be run using a normal Web browser or installed on any computer. Since it is written in Java it is platform and operating system independent. Image J is very extensible, object based and has a large international user community in many imaging disciplines. Extensions to Image J are written using the Java programming language and the internal macro recording facility. Image J handles multiple image formats useful in nuclear medicine including DICOM, RAW, BMP, JPG, Interfile, AVI and QT. Extensions have been written to process and determine gamma camera intrinsic and extrinsic uniformity, COR errors, planar extrinsic resolution and reconstructed spatial resolution. The testing and processing adhere closely to NEMA specified procedures and result in quantitative measures of performance traceable to NEMA and manufacturers specifications. Results and Conclusions: Extensions to Image J written specifically to process gamma camera acceptance test data have resulted in considerable decrease in time to complete the analysis and allows a consistent, vendor independent, method to measure performance of cameras from multiple vendors. Quality control images from multiple camera vendors are also easily processed in a consistent fashion. The availability of this or similar platform and vendor independent software should lead to more complete
Helicon modes in uniform plasmas. III. Angular momentum
International Nuclear Information System (INIS)
Stenzel, R. L.; Urrutia, J. M.
2015-01-01
Helicons are electromagnetic waves with helical phase fronts propagating in the whistler mode in magnetized plasmas and solids. They have similar properties to electromagnetic waves with angular momentum in free space. Helicons are circularly polarized waves carrying spin angular momentum and orbital angular momentum due to their propagation around the ambient magnetic field B 0 . These properties have not been considered in the community of researchers working on helicon plasma sources, but are the topic of the present work. The present work focuses on the field topology of helicons in unbounded plasmas, not on helicon source physics. Helicons are excited in a large uniform laboratory plasma with a magnetic loop antenna whose dipole axis is aligned along or across B 0 . The wave fields are measured in orthogonal planes and extended to three dimensions (3D) by interpolation. Since density and B 0 are uniform, small amplitude waves from loops at different locations can be superimposed to generate complex antenna patterns. With a circular array of phase shifted loops, whistler modes with angular and axial wave propagation, i.e., helicons, are generated. Without boundaries radial propagation also arises. The azimuthal mode number m can be positive or negative while the field polarization remains right-hand circular. The conservation of energy and momentum implies that these field quantities are transferred to matter which causes damping or reflection. Wave-particle interactions with fast electrons are possible by Doppler shifted resonances. The transverse Doppler shift is demonstrated. Wave-wave interactions are also shown by showing collisions between different helicons. Whistler turbulence does not always have to be created by nonlinear wave-interactions but can also be a linear superposition of waves from random sources. In helicon collisions, the linear and/or orbital angular momenta can be canceled, which results in a great variety of field topologies. The work
Clean focus, dose and CD metrology for CD uniformity improvement
Lee, Honggoo; Han, Sangjun; Hong, Minhyung; Kim, Seungyoung; Lee, Jieun; Lee, DongYoung; Oh, Eungryong; Choi, Ahlin; Kim, Nakyoon; Robinson, John C.; Mengel, Markus; Pablo, Rovira; Yoo, Sungchul; Getin, Raphael; Choi, Dongsub; Jeon, Sanghuck
2018-03-01
Lithography process control solutions require more exacting capabilities as the semiconductor industry goes forward to the 1x nm node DRAM device manufacturing. In order to continue scaling down the device feature sizes, critical dimension (CD) uniformity requires continuous improvement to meet the required CD error budget. In this study we investigate using optical measurement technology to improve over CD-SEM methods in focus, dose, and CD. One of the key challenges is measuring scanner focus of device patterns. There are focus measurement methods based on specially designed marks on scribe-line, however, one issue of this approach is that it will report focus of scribe line which is potentially different from that of the real device pattern. In addition, scribe-line marks require additional design and troubleshooting steps that add complexity. In this study, we investigated focus measurement directly on the device pattern. Dose control is typically based on using the linear correlation behavior between dose and CD. The noise of CD measurement, based on CD-SEM for example, will not only impact the accuracy, but also will make it difficult to monitor dose signature on product wafers. In this study we will report the direct dose metrology result using an optical metrology system which especially enhances the DUV spectral coverage to improve the signal to noise ratio. CD-SEM is often used to measure CD after the lithography step. This measurement approach has the advantage of easy recipe setup as well as the flexibility to measure critical feature dimensions, however, we observe that CD-SEM metrology has limitations. In this study, we demonstrate within-field CD uniformity improvement through the extraction of clean scanner slit and scan CD behavior by using optical metrology.
Response and Uniformity Studies of Directly Coupled Tiles
International Nuclear Information System (INIS)
Zutshi, Vishnu
2010-01-01
A finely-segmented scintillator-based calorimeter which capitalizes on the marriage of proven detection techniques with novel solid-state photo-detector devices such as Multi-pixel Photon Counters (MPPCs) is an interesting calorimetric system from the point of view of future detector design. A calorimeter system consisting of millions of channels will require a high degree of integration. The first steps towards this integration have already been facilitated by the small size and magnetic field immunity of the MPPCs. The photo-conversion occurs right at the tile, thus obviating the need for routing of long clear fibers. Similar considerations apply to the presence of wave-length shifting (WLS) fibers inside the tiles which couple it to the photo-detectors. Significant simplification in construction and assembly ensue if the MPPCs can be coupled directly to the scintillator tiles. Equally importantly, the total absence of fibers would offer greater flexibility in the choice of the transverse segmentation while enhancing the electro-mechanical integrability of the design. The NIU high-energy physics group has been studying the fiberless or direct-coupling option for some time now. Encouraging results on response and response uniformity have been obtained using radioactive sources. This MOU seeks to set up a framework to extend these tests using beams at the MTBF. The results will be relevant to high granularity scintillator/crystal electromagnetic and hadronic calorimetry. The tests involve a set of small directly-coupled tile counters fabricated at NIU which will be placed in the beam to study their response and response uniformity as a function of the incident position of the particles passing through them.
Response and Uniformity Studies of Directly Coupled Tiles
Energy Technology Data Exchange (ETDEWEB)
Zutshi, Vishnu
2010-04-02
A finely-segmented scintillator-based calorimeter which capitalizes on the marriage of proven detection techniques with novel solid-state photo-detector devices such as Multi-pixel Photon Counters (MPPCs) is an interesting calorimetric system from the point of view of future detector design. A calorimeter system consisting of millions of channels will require a high degree of integration. The first steps towards this integration have already been facilitated by the small size and magnetic field immunity of the MPPCs. The photo-conversion occurs right at the tile, thus obviating the need for routing of long clear fibers. Similar considerations apply to the presence of wave-length shifting (WLS) fibers inside the tiles which couple it to the photo-detectors. Significant simplification in construction and assembly ensue if the MPPCs can be coupled directly to the scintillator tiles. Equally importantly, the total absence of fibers would offer greater flexibility in the choice of the transverse segmentation while enhancing the electro-mechanical integrability of the design. The NIU high-energy physics group has been studying the fiberless or direct-coupling option for some time now. Encouraging results on response and response uniformity have been obtained using radioactive sources. This MOU seeks to set up a framework to extend these tests using beams at the MTBF. The results will be relevant to high granularity scintillator/crystal electromagnetic and hadronic calorimetry. The tests involve a set of small directly-coupled tile counters fabricated at NIU which will be placed in the beam to study their response and response uniformity as a function of the incident position of the particles passing through them.
Liu, Chengwei; Sui, Xiubao; Gu, Guohua; Chen, Qian
2018-02-01
For the uncooled long-wave infrared (LWIR) camera, the infrared (IR) irradiation the focal plane array (FPA) receives is a crucial factor that affects the image quality. Ambient temperature fluctuation as well as system power consumption can result in changes of FPA temperature and radiation characteristics inside the IR camera; these will further degrade the imaging performance. In this paper, we present a novel shutterless non-uniformity correction method to compensate for non-uniformity derived from the variation of ambient temperature. Our method combines a calibration-based method and the properties of a scene-based method to obtain correction parameters at different ambient temperature conditions, so that the IR camera performance can be less influenced by ambient temperature fluctuation or system power consumption. The calibration process is carried out in a temperature chamber with slowly changing ambient temperature and a black body as uniform radiation source. Enough uniform images are captured and the gain coefficients are calculated during this period. Then in practical application, the offset parameters are calculated via the least squares method based on the gain coefficients, the captured uniform images and the actual scene. Thus we can get a corrected output through the gain coefficients and offset parameters. The performance of our proposed method is evaluated on realistic IR images and compared with two existing methods. The images we used in experiments are obtained by a 384× 288 pixels uncooled LWIR camera. Results show that our proposed method can adaptively update correction parameters as the actual target scene changes and is more stable to temperature fluctuation than the other two methods.
DEFF Research Database (Denmark)
Kouchaki, Alireza; Iman-Eini, H.; Asaei, B.
2012-01-01
This paper presents a new algorithm based on characteristic equation of solar cells to determine the Maximum Power Point (MPP) of PV modules under partially shaded conditions (PSC). To achieve this goal, an analytic condition is introduced to determine uniform or non-uniform atmospheric condition...
Irradiation uniformity of spherical targets by multiple uv beams from OMEGA
International Nuclear Information System (INIS)
Beich, W.; Dunn, M.; Hutchison, R.
1984-01-01
Direct-drive laser fusion demands extremely high levels of irradiation uniformity to ensure uniform compression of spherical targets. The assessment of illumination uniformity of targets irradiated by multiple beams from the OMEGA facility is made with the aid of multiple beams spherical superposition codes, which take into account ray tracing and absorption and a detailed knowledge of the intensity distribution of each beam in the target plane. In this report, recent estimates of the irradiation uniformity achieved with 6 and 12 uv beams of OMEGA will be compared with previous measurements in the IR, and predictions will be made for the uv illumination uniformity achievable with 24 beams of OMEGA
Directory of Open Access Journals (Sweden)
Nguyen Xuan Tien
2016-09-01
Full Text Available This paper proposes a novel concentrator photovoltaic (CPV system with improved irradiation uniformity and system efficiency. CPV technology is very promising its for highly efficient solar energy conversion. A conventional CPV system usually uses only one optical component, such as a refractive Fresnel lens or a reflective parabolic dish, to collect and concentrate solar radiation on the solar cell surface. Such a system creates strongly non-uniform irradiation distribution on the solar cell, which tends to cause hot spots, current mismatch, and degrades the overall efficiency of the system. Additionally, a high-concentration CPV system is unable to collect diffuse solar radiation. In this paper, we propose a novel CPV system with improved irradiation uniformity and collection of diffuse solar radiation. The proposed system uses a Fresnel lens as a primary optical element (POE to concentrate and focus the sunlight and a plano-concave lens as a secondary optical element (SOE to uniformly distribute the sunlight over the surface of multi-junction (MJ solar cells. By using the SOE, the irradiance uniformity is significantly improved in the system. Additionally, the proposed system also captures diffuse solar radiation by using an additional low-cost solar cell surrounding MJ cells. In our system, incident direct solar radiation is captured by MJ solar cells, whereas incident diffuse solar radiation is captured by the low-cost solar cell. Simulation models were developed using a commercial optical simulation tool (LightTools™. The irradiance uniformity and efficiency of the proposed CPV system were analyzed, evaluated, and compared with those of conventional CPV systems. The analyzed and simulated results show that the CPV system significantly improves the irradiance uniformity as well as the system efficiency compared to the conventional CPV systems. Numerically, for our simulation models, the designed CPV with the SOE and low-cost cell provided
International Nuclear Information System (INIS)
Stevens, G.F.; Elliott, D.F.; Wood, R.W.
1965-05-01
Some correlations of forced convection burn-out data are based on the approximate linearity of the relationship between burn-out heat flux and the channel-averaged quality at the burn-out point. These correlations perform satisfactorily on data obtained from uniformly heated configurations. Therefore the further inference is sometimes made that the burn-out heat flux is uniquely related to the quality, and that the burn-out in non-uniformly heated configurations can be calculated from measurements made with uniform heating. This report presents burn-out data for Freon 12 flowing vertically upwards through both uniformly and non-uniformly heated round tubes. This data shows that the quality at burn-out does depend on the heat flux profile, and that the inference mentioned above is not justified. (author)
DEFF Research Database (Denmark)
Warnecke, Solveig
of the pharmaceutical drug, both during development and throughout the production. The usage of PAT tools is encouraged by the regulatory authorities, and therefore the interest in new and improved PAT tools is increasing. The main purpose of introducing Quality by Design (QbD) and PAT in pharmaceutical production...... practice in traditional pharmaceutical industry. In this thesis, three spectroscopic PAT tools are investigated, near-infrared-, terahertz-, and fluorescence-spectroscopy. These techniques have been evaluated with chemometrics and theory of sampling. The first study focused on the critical but rather...... overlooked sampling uncertainty that exist in all analytical measurements. The sampling error was studied using an example involving near infrared transmission (NIT) spectroscopy to study content of uniformity of five batches of escitalopram tablets, produced at different active pharmaceutical ingredients...
Uniform irradiation of adjustable target spots in high-power laser driver
International Nuclear Information System (INIS)
Jiang Xiujuan; Li Jinghui; Li Huagang; Li Yang; Lin Zunqi
2011-01-01
For smoothing and shaping the on-target laser patterns flexibly in high-power laser drivers, a scheme has been developed that includes a zoom lens array and two-dimensional smoothing by spectral dispersion (SSD). The size of the target pattern can be controlled handily by adjusting the focal length of the zoom lens array, while the profile of the pattern can be shaped by fine tuning the distance between the target and the focal plane of the principal focusing lens. High-frequency stripes inside the pattern caused by beamlet interference are wiped off by spectral dispersion. Detailed simulations indicate that SSD works somewhat differently for spots of different sizes. For small spots, SSD mainly smooths the intensity modulation of low-to-middle spatial frequency, while for large spots, SSD sweeps the fine speckle structure to reduce nonuniformity of middle-to-high frequency. Spatial spectra of the target patterns are given and their uniformity is evaluated.
Faes, Luca; Nollo, Giandomenico; Porta, Alberto
2012-03-01
The complexity of the short-term cardiovascular control prompts for the introduction of multivariate (MV) nonlinear time series analysis methods to assess directional interactions reflecting the underlying regulatory mechanisms. This study introduces a new approach for the detection of nonlinear Granger causality in MV time series, based on embedding the series by a sequential, non-uniform procedure, and on estimating the information flow from one series to another by means of the corrected conditional entropy. The approach is validated on short realizations of linear stochastic and nonlinear deterministic processes, and then evaluated on heart period, systolic arterial pressure and respiration variability series measured from healthy humans in the resting supine position and in the upright position after head-up tilt. Copyright Â© 2011 Elsevier Ltd. All rights reserved.
A method for generating skewed random numbers using two overlapping uniform distributions
International Nuclear Information System (INIS)
Ermak, D.L.; Nasstrom, J.S.
1995-02-01
The objective of this work was to implement and evaluate a method for generating skewed random numbers using a combination of uniform random numbers. The method provides a simple and accurate way of generating skewed random numbers from the specified first three moments without an a priori specification of the probability density function. We describe the procedure for generating skewed random numbers from unifon-n random numbers, and show that it accurately produces random numbers with the desired first three moments over a range of skewness values. We also show that in the limit of zero skewness, the distribution of random numbers is an accurate approximation to the Gaussian probability density function. Future work win use this method to provide skewed random numbers for a Langevin equation model for diffusion in skewed turbulence
A proposal for the use of uniform diagnostic criteria for gestational diabetes in Europe
DEFF Research Database (Denmark)
Benhalima, Katrien; Mathieu, Chantal; Damm, Peter
2015-01-01
Screening and diagnostic criteria for gestational diabetes (GDM) are inconsistent across Europe, and the development of a uniform GDM screening strategy is necessary. Such a strategy would create opportunities for more women to receive timely treatment for GDM. Developing a consensus on screening......-off values for diabetes outside pregnancy, with particular efforts made to screen high-risk groups. When screening for GDM is performed at 24 weeks' gestation or later, the proposal is now to use the 75 g OGTT with the new WHO diagnostic criteria for GDM. However, more research is necessary to evaluate...... for GDM in Europe is challenging, as populations are diverse and healthcare delivery systems also differ. The European Board & College of Obstetrics and Gynaecology (EBCOG) has responded to this challenge by appointing a steering committee, including members of the EBCOG and the Diabetic Pregnancy Study...
Reactivity effect of non-uniformly distributed fuel in fuel solution systems
International Nuclear Information System (INIS)
Hirano, Yasushi; Yamane, Yoshihiro; Nishina, Kojiro; Mitsuhashi, Ishi.
1991-01-01
A numerical method to determine the optimal fuel distribution for minimum critical mass, or maximum k-effective, is developed using the Maximum Principle in order to evaluate the maximum effect of non-uniformly distributed fuel on reactivity. This algorithm maximizes the Hamiltonian directly by an iterative method under a certain constraint-the maintenance of criticality or total fuel mass. It ultimately reaches the same optimal state of a flattened fuel importance distribution as another algorithm by Dam based on perturbation theory. This method was applied to two kinds of spherical cores with water reflector in the simulating reprocessing facility. In the slightly-enriched uranyl nitrate solution core, the minimum critical mass decreased by less than 1% at the optimal moderation state. In the plutonium nitrate solution core, the k-effective increment amounted up to 4.3% Δk within the range of present study. (author)
International Nuclear Information System (INIS)
Soussaline, F.; LeCoq, C.; Raynaud, C.; Kellershohn, C.
1982-09-01
The aim of this study is to evaluate the potential of the RIM technique when used in brain studies. The analytical Regulatorizing Iterative Method (RIM) is designed to provide fast and accurate reconstruction of tomographic images when non-uniform attenuation is to be accounted for. As indicated by phantom studies, this method improves the contrast and the signal-to-noise ratio as compared to those obtained with FBP (Filtered Back Projection) technique. Preliminary results obtained in brain studies using AMPI-123 (isopropil-amphetamine I-123) are very encouraging in terms of quantitative regional cellular activity. However, the clinical usefulness of this mathematically accurate reconstruction procedure is going to be demonstrated in our Institution, in comparing quantitative data in heart or liver studies where control values can be obtained
International Nuclear Information System (INIS)
Soussaline, F.; LeCoq, C.; Raynaud, C.; Kellershohn
1982-01-01
The potential of the Regularizing Iterative Method (RIM), when used in brain studies, is evaluated. RIM is designed to provide fast and accurate reconstruction of tomographic images when non-uniform attenuation is to be accounted for. As indicated by phantom studies, this method improves the contrast and the signal-to-noise ratio as compared to those obtained with Filtered Back Projection (FBP) technique. Preliminary results obtained in brain studies using isopropil-amphetamine I-123 (AMPI-123) are very encouraging in terms of quantitative regional cellular activity. However, the clinical usefulness of this mathematically accurate reconstruction procedure is going to be demonstrated, in comparing quantitative data in heart or liver studies where control values can be obtained
Symmetry and illumination uniformity requirements for high density laser-driven implosions
International Nuclear Information System (INIS)
Mead, W.C.; Lindl, J.D.
1976-01-01
As laser capabilities increase, implosions will be performed to achieve high densities. Criteria are discussed for formation of a low-density corona, preheated supersonically, which increases the tolerance of high convergence implosions to non-uniform illumination by utilizing thermal smoothing. We compare optimized double shell target designs without and with atmosphere production. Two significant penalties are incurred with atmosphere production using 1 μm laser light. First, a large initial shock at the ablation surface limits the pulse shaping flexibility, and degrades implosion performance. Second, the mass and heat capacity of the atmosphere reduce the energy delivered to the ablation surface and the driving pressures obtained for a given input energy. Improvement is possible using 2 μm light for the initial phase of the implosion. We present results of 2-D simulations which evaluate combined symmetry and stability requirements. At l = 8, the improvement produced in the example is a factor of 10, giving tolerance of 10 percent
Remer, D. S.
1977-01-01
A mathematical model is developed for calculating the life cycle costs for a project where the operating costs increase or decrease in a linear manner with time. The life cycle cost is shown to be a function of the investment costs, initial operating costs, operating cost gradient, project life time, interest rate for capital and salvage value. The results show that the life cycle cost for a project can be grossly underestimated (or overestimated) if the operating costs increase (or decrease) uniformly over time rather than being constant as is often assumed in project economic evaluations. The following range of variables is examined: (1) project life from 2 to 30 years; (2) interest rate from 0 to 15 percent per year; and (3) operating cost gradient from 5 to 90 percent of the initial operating costs. A numerical example plus tables and graphs is given to help calculate project life cycle costs over a wide range of variables.
Liquid jets injected into non-uniform crossflow
Tambe, Samir
An experimental study has been conducted with liquid jets injected transversely into a crossflow to study the effect of non-uniformities in the crossflow velocity distribution to the jet behavior. Two different non-uniform crossflows were created during this work, a shear-laden crossflow and a swirling crossflow. The shear-laden crossflow was generated by merging two independent, co-directional, parallel airstreams creating a shear mixing layer at the interface between them. The crossflow exhibited a quasi-linear velocity gradient across the height of the test chamber. By varying the velocities of the two airstreams, the sense and the slope of the crossflow velocity gradient could be changed. Particle Image Velocimetry (PIV) studies were conducted to characterize the crossflow. The parameter, UR, is defined as the ratio of the velocities of the two streams and governs the velocity gradient. A positive velocity gradient was observed for UR > 1 and a negative velocity gradient for UR Phase Doppler Particle Anemometry (PDPA) studies were conducted to study the penetration and atomization of 0.5 mm diameter water jets injected into this crossflow. The crossflow velocity gradient was observed to have a significant effect on jet penetration as well as the post breakup spray. For high UR (> 1), jet penetration increased and the Sauter Mean Diameter (SMD) distribution became more uniform. For low UR (Doppler Velocimetry (LDV) was used to study the crossflow velocities. The axial (Ux) and the tangential (Utheta) components of the crossflow velocity were observed to decrease with increasing radial distance away from the centerbody. The flow angle of the crossflow was smaller than the vane exit angle, with the difference increasing with the vane exit angle. Water jets were injected from a 0.5 mm diameter orifice located on a cylindrical centerbody. Multi-plane PIV measurements were conducted to study the penetration and droplet velocity distribution of the jets. The jets were
Hydra phantom applicability for carrying out tests of field uniformity in gamma cameras
International Nuclear Information System (INIS)
Aragao Filho, Geraldo L.; Oliveira, Alex C.H.
2014-01-01
Nuclear Medicine is a medical modality that makes use of radioactive material 'in vivo' in humans, making them a temporary radioactive source. The radiation emitted by the patient's body is detected by a specific equipment, called a gamma camera, creates an image showing the spatial and temporal biodistribution of radioactive material administered to the patient. Therefore, it's of fundamental importance a number of specific measures to make sure that procedure be satisfactory, called quality control. To Nuclear Medicine, quality control of gamma camera has the purpose of ensuring accurate scintillographic imaging, truthful and reliable for the diagnosis, guaranteeing visibility and clarity of details of structures, and also to determine the frequency and the need for preventive maintenance of equipment. To ensure the quality control of the gamma camera it's necessary to use some simulators, called phantom, used in Nuclear Medicine to evaluate system performance, system calibration and simulation of injuries. The goal of this study was to validate a new simulator for nuclear medicine, the Hydra phantom. The phantom was initially built for construction of calibration curves used in radiotherapy planning and quality control in CT. It has similar characteristics to specific phantoms in nuclear medicine, containing inserts and water area. Those inserts are regionally sourced materials, many of them are already used in the literature and based on information about density and interaction of radiation with matter. To verify its efficiency in quality control in Nuclear Medicine, was performed a test for uniformity field, one of the main tests performed daily, so we can verify the ability of the gamma camera to reproduce a uniform distribution of the administered activity in the phantom, been analysed qualitatively, through the image, and quantitatively, through values established for Central Field Of View (CFOV) and Useful Field Of View (UFOV). Also, was evaluated their
International Nuclear Information System (INIS)
Chen, Deshen; Qian, Hongliang; Wang, Huajie; Zhang, Gang; Fan, Feng; Shen, Shizhao
2017-01-01
Highlights: • Solar non-uniform temperature field test of a telescope’s reflector is conducted initially. • Time-varying distribution regularities are analyzed contrastively. • Simulation methods are proposed involving environmental factors and self-shadowing. • Refined discrimination method for the shadow distribution is put forward. • Validity of simulation methods is evaluated with the experimental data. - Abstract: To improve the ability of deep-space exploration, many astronomers around the world are actively engaged in the construction of large-aperture and high-precision radio telescopes. The temperature effect is one of three main factors affecting the reflector accuracy of radio telescopes. To study the daily non-uniform temperature field of the main reflector, experimental studies are first carried out with a 3-m-aperture radio telescope model. According to the test results for 16 working conditions, the distribution rule and time-varying regularity of the daily temperature field are summarized initially. Next, theoretical methods for the temperature field of the main reflector are studied considering multiple environmental parameters and self-shadows. Finally, the validity of the theoretical methods is evaluated with test results. The experimental study demonstrates that the non-uniform temperature distribution of the main reflector truly exists and should not be overlooked, and that the theoretical methods for the reflector temperature field proposed in this paper are effective. The research methods and conclusions can provide valuable references for thermal design, monitoring and control of similar high-precision radio telescopes.
WHEELSET AXLE WITH THE CAVITY OF UNIFORM CROSS SECTION
Directory of Open Access Journals (Sweden)
S. R. Kolesnykov
2014-10-01
Full Text Available Purpose. Due to operation in complex loading conditions, the rolling stock wheelsets should provide high reliability, since the train traffic safety largely depends on them. Design and technical condition of wheelsets affect the smoothness, intensity of forces generated by the interaction between the car and track, and the motion resistance. Specificity of the axle operation consists in the fact that it undergoes the bending stresses under loading. These stresses are unevenly distributed along the cross-sectional area, reaching the highest values in the outer fibers and the minimal values in the internal ones. This aspect sets the problem of replacement of the uniform cross section with the hollow cross section. The disadvantages of hollow axle design, which are used at the present time, should include a significant manufacturing complexity of the variable section cavity. The purpose is to develop a modernized design of the wheelset axle. Methodology. A construction of the hollow axle having an inner longitudinal cylindrical through hole of the constant diameter throughout its length was proposed. The item is made of steel seamless tube. The inner surface of the tube is treated by mechanical means to remove the voltage concentrations in the internal longitudinal cylindrical through hole, which has a constant diameter along the entire length of the axle. Findings. Application of this design will facilitate manufacturing of the hollow axle and the machining of the inner longitudinal through hole, while retaining all the use advantages of the hollow axle in the rolling stock wheel pairs. Another use advantage of the hollow axle of this design is the absence of partial heterogeneity of the metal, which is inevitably, occurs during the solid axles blanking. Originality. A new design of the wheelset hollow axle of railway rolling stock was proposed. Practical value. Introduction of the new design simplifying the manufacture and mechanical treatment of
Numerical prediction of dryout heat flux in vertical uniformly heated round tubes
International Nuclear Information System (INIS)
Okawa, Tomio; Kotani, Akio; Kataoka, Isao; Naito, Masanori
2003-01-01
Dryout heat fluxes in vertical uniformly heated round tubes were predicted using a film flow model. The correlations adopted in the present analysis were summarized as follows: (1) Entrainment rate and deposition rate were evaluated by the correlations whose validity was confirmed in wide range of thermal-hydraulic conditions. (2) In addition to the droplet entrainment due to interfacial shear force, the entrainment resulting from the boiling in liquid film was considered. (3) The vapor quality at the onset of annular flow was evaluated by the correlation based on the measurement of minimum droplet flowrate. (4) It was postulated that the droplet flowrate at the starting point of annular flow was to be approximated by that in equilibrium state. (5) The onset of critical heat flux condition was determined by the complete disappearance of liquid film. Though several assumptions were used in the present model, all the correlations adopted here were based on experimental data or considerations of the physical processes in annular flow. The resulting model required no parameters that should be adjusted from the measured data of critical heat flux. A number of experimental data of critical heat flux in forced flow of water in vertical uniformly heated round tubes were used to test the basic performance of the model. The comparisons between the calculated and measured critical heat fluxes showed that the predicted results by the present model agree with the experimental data fairly well if the flow pattern at burnout is considered annular flow. The predictive capability was not deteriorated even in the cases of small diameter tube, short length tube as well as low vapor quality at the onset of critical heat flux condition. (author)
International Nuclear Information System (INIS)
Narayan, P.; Suri, S.; Choudhary, S.R.
2001-01-01
In most general definition, noise in an image, is any variation that represents a deviation from truth. Noise sources in MRI can be systematic or random and statistical in nature. Data processing algorithms that smooth and enhance the edges by non-linear intensity assignments among other factors can affect the distribution of statistical noise. The SNR and image uniformity depends on the various parameters of NMR imaging system (viz. General system calibration, Gain coil tuning, AF shielding, coil loading, image processing and scan parameters like TE, TR, interslice distance, slice thickness, pixel size and matrix size). A study on SNR and image uniformity have been performed using standard head AF coil with different TR and the estimates of their variation are presented. A comparison between different techniques has also been evaluated using standard protocol of the Siemens Magnetom Vision Plus MRI system
Energy Technology Data Exchange (ETDEWEB)
Usmani, A. [Amec Foster Wheeler, Toronto, ON (Canada); Baughman, P.D. [Paul D. Baughman Consulting, Exeter, NH (United States)
2015-07-01
The Uniform Hazard Spectrum (UHS) is developed from a probabilistic seismic hazard assessment and represents a response spectrum for which the amplitude at each frequency has a specified and uniform (equal) probability of exceedance. The high spectral acceleration at high frequencies in the UHS can result mainly from small non-damaging low energy earthquakes. Historically Canadian and U.S. nuclear power plants have been designed using the standard shape spectrum given in CSA N289.3 or USNRC Regulatory Guide 1.60, which have maximum spectral accelerations in the lower (2-10 Hz.) frequency range. The impact of the high frequency content of UHS on the nuclear power plant SSCs is required to be assessed. This paper briefly describes the methodologies used for screening and evaluation of the effects of UHS high frequency content on the nuclear power SSCs that have been designed using the CSA N289.3 standard shape spectrum. (author)
Non-uniform sampling and wide range angular spectrum method
International Nuclear Information System (INIS)
Kim, Yong-Hae; Byun, Chun-Won; Oh, Himchan; Lee, JaeWon; Pi, Jae-Eun; Heon Kim, Gi; Lee, Myung-Lae; Ryu, Hojun; Chu, Hye-Yong; Hwang, Chi-Sun
2014-01-01
A novel method is proposed for simulating free space field propagation from a source plane to a destination plane that is applicable for both small and large propagation distances. The angular spectrum method (ASM) was widely used for simulating near field propagation, but it caused a numerical error when the propagation distance was large because of aliasing due to under sampling. Band limited ASM satisfied the Nyquist condition on sampling by limiting a bandwidth of a propagation field to avoid an aliasing error so that it could extend the applicable propagation distance of the ASM. However, the band limited ASM also made an error due to the decrease of an effective sampling number in a Fourier space when the propagation distance was large. In the proposed wide range ASM, we use a non-uniform sampling in a Fourier space to keep a constant effective sampling number even though the propagation distance is large. As a result, the wide range ASM can produce simulation results with high accuracy for both far and near field propagation. For non-paraxial wave propagation, we applied the wide range ASM to a shifted destination plane as well. (paper)
Uniformity analysis for a direct-drive laser fusion reactor
International Nuclear Information System (INIS)
Lund, L.D.; Skupsky, S.; Goldman, L.M.
1983-01-01
We show the results of an analysis of the uniformity for a direct-drive reactor using 20, 32, 60, or 96 beams. Several of these options achieve less than the 1% nonuniformity that is required. These options are considered for the cases where the solid angle fraction of the beam ports is 2% and 8%. The analysis is facilitated by separating the contributions due to the geometrical effects related to the number and orientation of the beams from those due to the spatial profile of the individual beams. Emphasis is placed on the wavelength of the nonuniformities, as the shorter wavelength nonuniformities are more easily smoothed by thermal conduction within the target. The analysis demonstrates that the longer wavelengths can be minimized by suitable choices of geometry and by maintaining beam balance, whereas the shorter wavelength nonuniformities can be reduced by optimizing parameters such as the focal position and the spatial intensity profile of each beam. The tolerances required for beam-to-beam energy balance will be discussed
Terrestrial carbon cycle affected by non-uniform climate warming
International Nuclear Information System (INIS)
Jianyang Xia; Yiqi Luo; Jiquan Chen; Shilong Piao; Ciais, Philippe; Shiqiang Wan
2014-01-01
Feedbacks between the terrestrial carbon cycle and climate change could affect many ecosystem functions and services, such as food production, carbon sequestration and climate regulation. The rate of climate warming varies on diurnal and seasonal timescales. A synthesis of global air temperature data reveals a greater rate of warming in winter than in summer in northern mid and high latitudes, and the inverse pattern in some tropical regions. The data also reveal a decline in the diurnal temperature range over 51% of the global land area and an increase over only 13%, because night-time temperatures in most locations have risen faster than daytime temperatures. Analyses of satellite data, model simulations and in situ observations suggest that the impact of seasonal warming varies between regions. For example, spring warming has largely stimulated ecosystem productivity at latitudes between 30 degrees and 90 degrees N, but suppressed productivity in other regions. Contrasting impacts of day- and night-time warming on plant carbon gain and loss are apparent in many regions. We argue that ascertaining the effects of non-uniform climate warming on terrestrial ecosystems is a key challenge in carbon cycle research. (authors)
Spiral wobbling beam illumination uniformity in HIF fuel target implosion
Directory of Open Access Journals (Sweden)
Kawata S.
2013-11-01
Full Text Available A few % wobbling-beam illumination nonuniformity is realized in heavy ion inertial confinement fusion (HIF throughout the heavy ion beam (HIB driver pulse by a newly introduced spiraling beam axis motion in the first two rotations. The wobbling HIB illumination was proposed to realize a uniform implosion in HIF. However, the initial imprint of the wobbling HIBs was a serious problem and introduces a large unacceptable energy deposition nonuniformity. In the wobbling HIBs illumination, the illumination nonuniformity oscillates in time and space. The oscillating-HIB energy deposition may produce a time-dependent implosion acceleration, which reduces the Rayleigh-Taylor (R-T growth [Laser Part. Beams 11, 757 (1993, Nuclear Inst. Methods in Phys. Res. A 606, 152 (2009, Phys. Plasmas 19, 024503 (2012] and the implosion nonuniformity. The wobbling HIBs can be generated in HIB accelerators and the oscillating frequency may be several 100 MHz ∼ 1 GHz [Phys. Rev. Lett. 104, 254801 (2010]. Three-dimensional HIBs illumination computations present that the few % wobbling HIBs illumination nonuniformity oscillates with the same wobbling HIBs frequency.
Shape memory polymers based on uniform aliphatic urethane networks
Energy Technology Data Exchange (ETDEWEB)
Wilson, T S; Bearinger, J P; Herberg, J L; Marion III, J E; Wright, W J; Evans, C L; Maitland, D J
2007-01-19
Aliphatic urethane polymers have been synthesized and characterized, using monomers with high molecular symmetry, in order to form amorphous networks with very uniform supermolecular structures which can be used as photo-thermally actuable shape memory polymers (SMPs). The monomers used include hexamethylene diisocyanate (HDI), trimethylhexamethylenediamine (TMHDI), N,N,N{prime},N{prime}-tetrakis(hydroxypropyl)ethylenediamine (HPED), triethanolamine (TEA), and 1,3-butanediol (BD). The new polymers were characterized by solvent extraction, NMR, XPS, UV/VIS, DSC, DMTA, and tensile testing. The resulting polymers were found to be single phase amorphous networks with very high gel fraction, excellent optical clarity, and extremely sharp single glass transitions in the range of 34 to 153 C. Thermomechanical testing of these materials confirms their excellent shape memory behavior, high recovery force, and low mechanical hysteresis (especially on multiple cycles), effectively behaving as ideal elastomers above T{sub g}. We believe these materials represent a new and potentially important class of SMPs, and should be especially useful in applications such as biomedical microdevices.
Resource reflecting functor and its application to non-uniformity
Srinivasan, Priyaa Varshinee; Sanders, Barry C.; Cockett, Robin
In this work, we formulate an abstract approach to translate one resource theory to another. We adopt the notion of resource theories as partitioned symmetric monoidal categories and extend this notion by considering resource-reflecting functors between resource theories. A functor F is a structure preserving map and F is said to be resource-reflecting if F (g) being a free transformation implies that the transformation g is also free. Thus, a resource-reflecting functor demonstrates that the existence of a free transformation between two resources in the domain resource theory can be inferred from the existence of a free transformation in the codomain theory. As an example, we construct one such functor from the resource theory of non-uniformity to a resource theory of majorization. Thus, our work lays a foundation for expressing similarities between resource theories and for applying results achieved in one resource theory to another. An abstract approach to the translation between theories enables common patterns to be identified between resource theories thereby reducing the effort of solving the same problem for different theories. BCS appreciates financial support from Alberta Innovates, NSERC, China's 1000 Talent Plan and the IQIM, which is an NSF Physics Frontiers Centre (NSF Grant PHY-1125565) with support of the Gordon and Betty Moore Foundation (GBMF-2644).
Uniformity on the grid via a configuration framework
International Nuclear Information System (INIS)
Igor V Terekhov et al.
2003-01-01
As Grid permeates modern computing, Grid solutions continue to emerge and take shape. The actual Grid development projects continue to provide higher-level services that evolve in functionality and operate with application-level concepts which are often specific to the virtual organizations that use them. Physically, however, grids are comprised of sites whose resources are diverse and seldom project readily onto a grid's set of concepts. In practice, this also creates problems for site administrators who actually instantiate grid services. In this paper, we present a flexible, uniform framework to configure a grid site and its facilities, and otherwise describe the resources and services it offers. We start from a site configuration and instantiate services for resource advertisement, monitoring and data handling; we also apply our framework to hosting environment creation. We use our ideas in the Information Management part of the SAM-Grid project, a grid system which will deliver petabyte-scale data to the hundreds of users. Our users are High Energy Physics experimenters who are scattered worldwide across dozens of institutions and always use facilities that are shared with other experiments as well as other grids. Our implementation represents information in the XML format and includes tools written in XQuery and XSLT
Temperature uniformity control in RTP using multivariable adaptive control
Energy Technology Data Exchange (ETDEWEB)
Morales, S.; Dahhou, B.; Dilhac, J.M. [Centre National de la Recherche Scientifique (CNRS), 31 - Toulouse (France); Morales, S.
1995-12-31
In Rapid Thermal Processing (RTP) control of the wafer temperature during all processing to get good trajectory following, together with spatial temperature uniformity, is essential. It is well know as RTP process is nonlinear, classical control laws are not very efficient. In this work, the authors aim at studying the applicability of MIMO (Multiple Inputs Multiple Outputs) adaptive techniques to solve the temperature control problems in RTP. A multivariable linear discrete time CARIMA (Controlled Auto Regressive Integrating Moving Average) model of the highly non-linear process is identified on-line using a robust identification technique. The identified model is used to compute an infinite time LQ (Linear Quadratic) based control law, with a partial state reference model. This reference model smooths the original setpoint sequence, and at the same time gives a tracking capability to the LQ control law. After an experimental open-loop investigation, the results of the application of the adaptive control law are presented. Finally, some comments on the future difficulties and developments of the application of adaptive control in RTP are given. (author) 13 refs.
Standardization of the intrinsic uniformity control of the gamma cameras
International Nuclear Information System (INIS)
Solsona Harster, Lluis; Llopis Gonzalez, David; Pavia Segura, Javier
2001-01-01
Objective: To verify the Intrinsic Uniformity (Iu) results using different acquisition parameters in the weekly gamma camera Quality Control (Qc). Material And Methods: We made 4 experiments using Tc99 sources and modifying the orientation, distance, activity an volume parameters of a source in ten detectors with I Na photomultipliers applying the following acquisition conditions: 4000 Kc, the source 2 m far from the geometrical centre of the detectors, 0.1 ml into 1 ml syringe, and 150 Tc99m ?Ci. Results: We found better results when the distance between detector/source is getting longer, but the better point we found between 1,5 and 2 m. We also found necessary the collimator position was parallel respect to the geometrical centre field of view, because a little deviation of only two degrees can offer a bad result between +0.5%. We study the dose that we should use, and the results show us that better results are not in the highest or smallest values of activity into the source. In volume parameters, we can see that if we use a source highest than 1 ml we obtained better results. Conclusion: Following our results in the variation of IU values as for as the distance, rotation detector/source, dose and source activity, we recommend to perform this QC applying NEMA rules in same conditions every week and using the different parameters of our study to obtain better IU (Au)
Frontal Conversion and Uniformity in 3D Printing by Photopolymerisation.
Vitale, Alessandra; Cabral, João T
2016-09-07
We investigate the impact of the non-uniform spatio-temporal conversion, intrinsic to photopolymerisation, in the context of light-driven 3D printing of polymers. The polymerisation kinetics of a series of model acrylate and thiol-ene systems, both neat and doped with a light-absorbing dye, is investigated experimentally and analysed according to a descriptive coarse-grained model for photopolymerisation. In particular, we focus on the relative kinetics of polymerisation with those of 3D printing, by comparing the evolution of the position of the conversion profile ( z f ) to the sequential displacement of the object stage ( ∆z ). After quantifying the characteristic sigmoidal monomer-to-polymer conversion of the various systems, with a combination of patterning experiments, FT-IR mapping, and modelling, we compute representative regimes for which z f is smaller, commensurate with, or larger than ∆z . While non-monotonic conversion can be detrimental to 3D printing, for instance in causing differential shrinkage of inhomogeneity in material properties, we identify opportunities for facile fabrication of modulated materials in the z -direction (i.e., along the illuminated axis). Our simple framework and model, based on directly measured parameters, can thus be employed in photopolymerisation-based 3D printing, both in process optimisation and in the precise design of complex, internally stratified materials by coupling the z -stage displacement and frontal polymerisation kinetics.
Uniform electron gases. I. Electrons on a ring.
Loos, Pierre-François; Gill, Peter M W
2013-04-28
We introduce a new paradigm for one-dimensional uniform electron gases (UEGs). In this model, n electrons are confined to a ring and interact via a bare Coulomb operator. We use Rayleigh-Schrödinger perturbation theory to show that, in the high-density regime, the ground-state reduced (i.e., per electron) energy can be expanded as ε(r(s),n)=ε0(n)r(s)(-2)+ε1(n)r(s)(-1)+ε2(n)+ε3(n)r(s+)⋯ , where r(s) is the Seitz radius. We use strong-coupling perturbation theory and show that, in the low-density regime, the reduced energy can be expanded as ε(r(s),n)=η0(n)r(s)(-1)+η1(n)r(s)(-3/2)+η2(n)r(s)(-2)+⋯ . We report explicit expressions for ε0(n), ε1(n), ε2(n), ε3(n), η0(n), and η1(n) and derive the thermodynamic (large-n) limits of each of these. Finally, we perform numerical studies of UEGs with n = 2, 3, [ellipsis (horizontal)], 10, using Hylleraas-type and quantum Monte Carlo methods, and combine these with the perturbative results to obtain a picture of the behavior of the new model over the full range of n and r(s) values.
Frontal Conversion and Uniformity in 3D Printing by Photopolymerisation
Directory of Open Access Journals (Sweden)
Alessandra Vitale
2016-09-01
Full Text Available We investigate the impact of the non-uniform spatio-temporal conversion, intrinsic to photopolymerisation, in the context of light-driven 3D printing of polymers. The polymerisation kinetics of a series of model acrylate and thiol-ene systems, both neat and doped with a light-absorbing dye, is investigated experimentally and analysed according to a descriptive coarse-grained model for photopolymerisation. In particular, we focus on the relative kinetics of polymerisation with those of 3D printing, by comparing the evolution of the position of the conversion profile (zf to the sequential displacement of the object stage (∆z. After quantifying the characteristic sigmoidal monomer-to-polymer conversion of the various systems, with a combination of patterning experiments, FT-IR mapping, and modelling, we compute representative regimes for which zf is smaller, commensurate with, or larger than ∆z. While non-monotonic conversion can be detrimental to 3D printing, for instance in causing differential shrinkage of inhomogeneity in material properties, we identify opportunities for facile fabrication of modulated materials in the z-direction (i.e., along the illuminated axis. Our simple framework and model, based on directly measured parameters, can thus be employed in photopolymerisation-based 3D printing, both in process optimisation and in the precise design of complex, internally stratified materials by coupling the z-stage displacement and frontal polymerisation kinetics.
Spatial Signature Estimation with an Uncalibrated Uniform Linear Array
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Xiang Cao
2015-06-01
Full Text Available In this paper, the problem of spatial signature estimation using a uniform linear array (ULA with unknown sensor gain and phase errors is considered. As is well known, the directions-of-arrival (DOAs can only be determined within an unknown rotational angle in this array model. However, the phase ambiguity has no impact on the identification of the spatial signature. Two auto-calibration methods are presented for spatial signature estimation. In our methods, the rotational DOAs and model error parameters are firstly obtained, and the spatial signature is subsequently calculated. The first method extracts two subarrays from the ULA to construct an estimator, and the elements of the array can be used several times in one subarray. The other fully exploits multiple invariances in the interior of the sensor array, and a multidimensional nonlinear problem is formulated. A Gauss–Newton iterative algorithm is applied for solving it. The first method can provide excellent initial inputs for the second one. The effectiveness of the proposed algorithms is demonstrated by several simulation results.
Direction Finding for Bistatic MIMO Radar with Uniform Circular Array
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Cao Yunhe
2013-01-01
Full Text Available A method of direction of arrival (DOA and direction of departure (DOD angle estimation based on polynomial rooting for bistatic multiple-input multiple-output (MIMO radar with uniform circular array (UCA configuration is proposed in this paper. The steering vector of the UCA is firstly transformed into a steering vector with a Vandermonde structure by using the Jacobi-Anger expansion. Then the null-spectrum function of the MIMO radar can be written as an expression in which the transmit and receive steering vectors are decoupled. Finally, a two-step polynomial rooting is used to estimate DOA and DOD of targets instead of two-dimensional multiple signal classification (MUSIC search method for bistatic UCA MIMO radar. The angle estimation performance of the proposed method is similar to that of the MUSIC spectral search method, but the computation burden of the proposed polynomial rooting algorithm is much lower than that of the conventional MUSIC method. The simulation results of the proposed algorithm are presented and the performances are investigated and analyzed.
Bayesian inference from count data using discrete uniform priors.
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Federico Comoglio
Full Text Available We consider a set of sample counts obtained by sampling arbitrary fractions of a finite volume containing an homogeneously dispersed population of identical objects. We report a Bayesian derivation of the posterior probability distribution of the population size using a binomial likelihood and non-conjugate, discrete uniform priors under sampling with or without replacement. Our derivation yields a computationally feasible formula that can prove useful in a variety of statistical problems involving absolute quantification under uncertainty. We implemented our algorithm in the R package dupiR and compared it with a previously proposed Bayesian method based on a Gamma prior. As a showcase, we demonstrate that our inference framework can be used to estimate bacterial survival curves from measurements characterized by extremely low or zero counts and rather high sampling fractions. All in all, we provide a versatile, general purpose algorithm to infer population sizes from count data, which can find application in a broad spectrum of biological and physical problems.
Luminescence from cavitation bubbles deformed in uniform pressure gradients
Supponen, Outi; Obreschkow, Danail; Kobel, Philippe; Farhat, Mohamed
2017-09-01
Presented here are observations that demonstrate how the deformation of millimetric cavitation bubbles by a uniform pressure gradient quenches single-collapse luminescence. Our innovative measurement system captures a broad luminescence spectrum (wavelength range, 300-900 nm) from the individual collapses of laser-induced bubbles in water. By varying the bubble size, driving pressure, and perceived gravity level aboard parabolic flights, we probed the limit from aspherical to highly spherical bubble collapses. Luminescence was detected for bubbles of maximum radii within the previously uncovered range, R0=1.5 -6 mm, for laser-induced bubbles. The relative luminescence energy was found to rapidly decrease as a function of the bubble asymmetry quantified by the anisotropy parameter ζ , which is the dimensionless equivalent of the Kelvin impulse. As established previously, ζ also dictates the characteristic parameters of bubble-driven microjets. The threshold of ζ beyond which no luminescence is observed in our experiment closely coincides with the threshold where the microjets visibly pierce the bubble and drive a vapor jet during the rebound. The individual fitted blackbody temperatures range between Tlum=7000 and Tlum=11 500 K but do not show any clear trend as a function of ζ . Time-resolved measurements using a high-speed photodetector disclose multiple luminescence events at each bubble collapse. The averaged full width at half-maximum of the pulse is found to scale with R0 and to range between 10 and 20 ns.
Numerical MHD study for plasmoid instability in uniform resistivity
Shimizu, Tohru; Kondoh, Koji; Zenitani, Seiji
2017-11-01
The plasmoid instability (PI) caused in uniform resistivity is numerically studied with a MHD numerical code of HLLD scheme. It is shown that the PI observed in numerical studies may often include numerical (non-physical) tearing instability caused by the numerical dissipations. By increasing the numerical resolutions, the numerical tearing instability gradually disappears and the physical tearing instability remains. Hence, the convergence of the numerical results is observed. Note that the reconnection rate observed in the numerical tearing instability can be higher than that of the physical tearing instability. On the other hand, regardless of the numerical and physical tearing instabilities, the tearing instability can be classified into symmetric and asymmetric tearing instability. The symmetric tearing instability tends to occur when the thinning of current sheet is stopped by the physical or numerical dissipations, often resulting in the drastic changes in plasmoid chain's structure and its activity. In this paper, by eliminating the numerical tearing instability, we could not specify the critical Lundquist number Sc beyond which PI is fully developed. It suggests that Sc does not exist, at least around S = 105.
Non-Uniform Cathode Emission Studies of a MIG Gun
Marchewka, C. D.; Shapiro, M. A.; Sirigiri, J. R.; Temkin, R. J.
2004-11-01
We present the initial results of the modeling of the effect of emission non-uniformity in 96 kV, 40 A Magnetron Injection Gun (MIG) of a 1.5 MW 110 GHz gyrotron using a 3D gun simulation code. The azimuthal emission nonuniformity can lead to increased mode competition and an overall decreased efficiency of the device [1]. The electron beam is modeled from the cathode to a downstream position where the velocity spread saturates using the AMAZE 3D suite of codes. After bench marking the results of the 3D code with 2D codes such as TRAK2D and EGUN, the emitter was modified to simulate asymmetric emission from the cathode to gain an understanding into the effects of inhomogeneous beam current density on the velocity spread and pitch factor of the electron beam. [1] G. S. Nusinovich, A.N. Vlasov, M. Botton, T. M. Antonsen, Jr., S. Cauffman, K. Felch, ``Effect of the azimuthal inhomogeneity of electron emission on gyrotron operation,'' Phys. Plasmas, vol. 8, no. 7, pp. 3473-3479, 2001