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气象观测场在汽车试验场中的应用研究
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作者 陈海建 《时代汽车》 2024年第14期172-174,178,共4页
汽车试验场作为汽车开展道路测试的重要场所,用于验证汽车产品的品质以及可靠性。除了场地道路外,气象条件作为汽车道路测试的重要一环,在《GB/T12534-1990汽车道路试验方法通则》中也有明确要求,如:试验时应是无雨无雾天气,相对湿度小... 汽车试验场作为汽车开展道路测试的重要场所,用于验证汽车产品的品质以及可靠性。除了场地道路外,气象条件作为汽车道路测试的重要一环,在《GB/T12534-1990汽车道路试验方法通则》中也有明确要求,如:试验时应是无雨无雾天气,相对湿度小于95%,气温0-40℃,风速不大于3m/s。同时气象条件也作为试验场道路管控的重要依据,实时风速、雨量、能见度等信息为场地管理者发布限速、限行、封场等通知提供必要参考依据,直接影响道路测试安全管控的及时性。因此,文章从气象观测场的建设、气象服务、异常天气道路管控等方面开展气象观测场在汽车试验场中的应用研究。 展开更多
关键词 products. In addition to the SITE roads METEOROLOGICAL conditions are an important part of AUTOMOTIVE ROAD testing and there are also clear requirements in the GB/T12534-1990 General Rules for AUTOMOTIVE ROAD Test Methods. For example the test should be conducted in rain and fog free weather with a relative humidity of less than 95% a temperature of 0-40 and a wind SPEED of no more than 3m/s. At the same time METEOROLOGICAL conditions also serve as an important basis for ROAD control in the test site. Real time information such as wind SPEED rainfall and visibility provides necessary reference for SITE managers to issue notices on SPEED limits SITE closures and trac restrictions directly aecting the timeliness of ROAD testing safety control. Therefore this article conducts research on the application of METEOROLOGICAL observation SITES in AUTOMOTIVE testing SITES from the construction of METEOROLOGICAL observation SITES METEOROLOGICAL services and abnormal weather ROAD control.
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Standardization in laboratory medicine: Adoption of common reference intervals to the Croatian population
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作者 Zlata Flegar-Me?tri? Sonja Perkov Andrea Radeljak 《World Journal of Methodology》 2016年第1期93-100,共8页
Considering the fact that the results of laboratory tests provide useful information about the state of health of patients, determination of reference value is considered an intrinsic part in the development of labora... Considering the fact that the results of laboratory tests provide useful information about the state of health of patients, determination of reference value is considered an intrinsic part in the development of laboratory medi-cine. There are still huge differences in the analytical methods used as well as in the associated reference intervals which could consequently significantly affect the proper assessment of patient health. In a constant effort to increase the quality of patients' care, there are numerous international initiatives for standardiza-tion and/or harmonization of laboratory diagnostics in order to achieve maximum comparability of laboratory test results and improve patient safety. Through the standardization and harmonization processes of analytical methods the ability to create unique reference intervals is achieved. Such reference intervals could be applied globally in all laboratories using methods traceable to the same reference measuring system and analysing the biological samples from the populations with similar socio-demographic and ethnic characteristics. In this review we outlined the results of the harmonization processes in Croatia in the field of population based reference intervals for clinically relevant blood and serum constituents which are in accordance with ongoing activity for worldwide standardization and harmonization based on traceability in laboratory medicine. 展开更多
关键词 Calibration traceability Applicability of reference INTERVALS Harmonization and standardisation External quality assessment International Federation of Clinical Chemistry enzyme reference methods Amino- TRANSFERASE "common" reference INTERVALS CREATININE enzymatic method
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An Approach for Using of Poly Glycolic Acid (PGA) in Reference Standard Dosimetry: PGA/ESR Dosimetry System Response Curve and Post Irradiation Stability
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作者 Arbi Mejri Haikel Jelassi +2 位作者 Khaled Farah Ahmad Hichem Hamzaoui Hichem Eleuch 《World Journal of Nuclear Science and Technology》 2012年第3期73-79,共7页
Reference Standard Dosimeters are used to calibrate radiation environments and routine dosimeters. It can also be used in routine dosimetry applications for radiation processing where higher quality dosimetry measurem... Reference Standard Dosimeters are used to calibrate radiation environments and routine dosimeters. It can also be used in routine dosimetry applications for radiation processing where higher quality dosimetry measurements are required. Electron Spin Resonance (ESR) is a well-established Reference Standard Dosimetry system in industrial applications of ionising radiation, and its use is also proposed in radiation therapy and accident dosimetry. In the present experimental work, PGA solid state dosimeter (SSD) has been investigated using ESR spectroscopy to study the gamma radiation response of this material and to evaluate its dosimetric characteristics: dose response, room temperature fading, heat treatment effect during post-irradiation storage. Results obtained up to now confirm that PGA seems to be suitable material for ESR dosimetry applications. 展开更多
关键词 DOSIMETRY Solid State Dosimeter (SSD) POLY Glycolic Acid (PGA) Electron Spin Resonance (ESR) reference Standard Dosimetery Post-Irradiation Thermal Treatments Fading Behaviour
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Absolute Internal Energy of the Real Gas 被引量:1
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作者 Albrecht Elsner 《Engineering(科研)》 2017年第4期361-375,共15页
The internal energy U of the real, neutral-gas particles of total mass M in the volume V can have positive and negative values, whose regions are identified in the state chart of the gas. Depending on the relations am... The internal energy U of the real, neutral-gas particles of total mass M in the volume V can have positive and negative values, whose regions are identified in the state chart of the gas. Depending on the relations among gas temperature T, pressure p and mass-specific volume v=V/M, the mass exists as a uniform gas of freely-moving particles having positive values U or as more or less structured matter with negative values U. In the regions U>0?above the critical point [Tc , pc , vc] it holds that p(T,v)>pc and v>vc, and below the critical point it holds that p(T,v)c and v>vv , where vv is the mass-specific volume of saturated vapor. In the adjacent regions with negative internal energy values Uc is the line of equal positive and negative energy contributions and thus represents a line of vanishing internal energy ?U=0. At this level along the critical isochor the ever present microscopic fluctuations in energy and density become macroscopic fluctuations as the pressure decreases on approaching the critical point;these are to be observed in experiments on the critical opalescence. Crossing the isochor vc from U>0 to UΔU>0 happens without any discontinuity. The saturation line vv also separates the regions between U>0 and U , but does not represent a line U=0. The internal-energy values of saturated vapor Uv and condensate Ui can be determined absolutely as functions of vapor pressure p and densities (M/V)v and (M/V)i , repectively, yielding the results Uiv, U=Ui+Uvc and U=Ui=Uv=0 at the critical point. Crossing the line Vv from U=Uv>0 to U=Uv+UiΔU=-Ui>0 to be removed from the particle system. The thermodynamic and quantum-mechanical formulations of the internal energy of a particle system only agree if both the macroscopic and microscopic energy scales have the same absolute energy reference value 0. Arguments for the energy reference value in the state of transition from bound to freely- moving particles in macroscopic classical and microscopic quantum particle systems are discussed. 展开更多
关键词 ENERGY reference Value Zero in Microscopic and Macroscopic Particle Systems STATE of Transition from Bound to Freely-Moving Particles INTERNAL ENERGY Regions in the STATE Chart of Gas CRITICAL Point and CRITICAL Isochor Loci of VANISHING INTERNAL ENERGY CRITICAL OPALESCENCE BEC Calculation of INTERNAL Energies of Saturated Liquid and Vapor
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一个传奇的品牌,一个经典的系列 KEF与TheReference系列的故事
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作者 家祺 《视听前线》 2024年第1期2-7,共6页
回顾2023年,KEF的产品又再斩获众多不同定位、不同类型的各种Hi-Fi音响奖项。在更新MAT技术后,KEF全线新Meta系列在音质方面的提升是备受肯定的。其中最受瞩目的自然是KEF当家的Reference系列了。Reference (参考)系列作为KEF产品线中... 回顾2023年,KEF的产品又再斩获众多不同定位、不同类型的各种Hi-Fi音响奖项。在更新MAT技术后,KEF全线新Meta系列在音质方面的提升是备受肯定的。其中最受瞩目的自然是KEF当家的Reference系列了。Reference (参考)系列作为KEF产品线中一个非常重要的高端系列,历经多次变革,至今依然是KEF产品线当中最受发烧友欢迎的系列。它不仅是嫡传KEF每个时期应用于旗舰级先进技术的产品,更是KEF最新技术的普及应用和向下移植的承载者。这个刚刚迈过第50个年头的经典系列在这么多年来能够持续获得发烧友和媒体的喜爱实属不易,这个系列是如何一步一步成为经典的?我们来回顾一下KEF这个品牌与参考系列的发展。 展开更多
关键词 KEF reference 线
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HEXAGON GLOBAL REFERENCE活动桥式测量机
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《现代制造》 2005年第15期126-126,共1页
GLOBAL REFERENCE具备非常高的扫描效率,可以为具有最复杂几何形状的工件提供测量解决方案。采用LEITZ的TRAX测头技术,具备极高的测量精度,重复性好。配置当今功能最为完善的软件之一:QUINDOS,使得用户在完成箱体类工件测量的同时... GLOBAL REFERENCE具备非常高的扫描效率,可以为具有最复杂几何形状的工件提供测量解决方案。采用LEITZ的TRAX测头技术,具备极高的测量精度,重复性好。配置当今功能最为完善的软件之一:QUINDOS,使得用户在完成箱体类工件测量的同时,还可完成包括多种曲面元素,诸如叶片、齿轮和压缩机螺杆以及轮廓、自由曲面等多种复杂几何形状的测量。独特的TRICISION(精密三角梁)横梁设计,提供了良好的刚性质量比。轻合金桥架,与传统设计相比较刚性提高了25%, 展开更多
关键词 reference GLOBAL 齿
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Comparison of Five Endogenous Reference Genes for Specific PCR Detection and Quantification of Rice
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作者 ZHANG Xiujie JIN Wujun +4 位作者 XU Wentao LI Xiaying SHANG Ying LI Sha OUYANG Hongsheng 《Rice science》 SCIE CSCD 2019年第4期248-256,I0006,I0007,共11页
Endogenous reference genes (ERGs) provide vital information regarding genetically modified organisms (GMOs). The successful detection of ERGs can identity GMOs and the source of genes, verify stability and reliability... Endogenous reference genes (ERGs) provide vital information regarding genetically modified organisms (GMOs). The successful detection of ERGs can identity GMOs and the source of genes, verify stability and reliability of the detection system, and calculate the level of genetically modified (GM) ingredients in mixtures. The reported ERGs in rice include sucrose-phosphate synthase (SPS), phospholipase D (PLD), RBE4 and rice root-specific GOS9 genes. Based on the characteristics of ERGs, a new ERG gene, phosphoenolpyruvate carboxylase (PEPC), was selected, and further compared with the four existing genes. A total of 18 rice varieties and 29 non-rice crops were used to verify the interspecies specificity, intraspecies consistency, sensitivity, stability and reliability of these five ERGs using qualitative and quantitative PCR. Qualitative detection indicated that SPS and PEPC displayed sufficient specificity, and the detection sensitivity was 0.05% and 0.005%, respectively. Although the specificity of both RBE4 and GOS9 were adequate, the amplicons were small and easily confused with primer dimers. Non-specific amplification of the PLD gene was present in maize and potato. Real-time quantitative PCR detection indicated that PLD, SPS and PEPC displayed good specificity, with R2 of the standard curve greater than 0.98, while the amplification efficiency ranged between 90% and 110%. Both the detection sensitivities of PLD and PEPC were five copies and that of SPS was ten copies. RBE4 showed typical amplification in maize, beet and Arabidopsis, while GOS9 was found in maize, tobacco and oats. PEPC exhibited excellent detection sensitivity and species specificity, which made it a potentially useful application in GM-rice supervision and administration. Additionally, SPS and PLD are also suitable for GM-rice detection. This study effectively established a foundation for GMO detection, which not only provides vital technical support for GMO identification, but also is of great significance for enhancing the comparability of detection results, and the standardization of ERG testing in GM-rice. 展开更多
关键词 ENDOGENOUS reference GENE RICE genetically modified crop PHOSPHOENOLPYRUVATE CARBOXYLASE GENE sucrose-phosphate synthase GENE phospholipase D GENE starch branching enzyme 4 GENE RICE root-specific GOS9 GENE
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Refining the Reference Values of Diers 4D Formetric System and Introducing a Qualitative Spine Profile Based on Percentile Ranking 被引量:1
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作者 Luc Peeters Grégoire Lason +1 位作者 Geert Byttebier Frank Comhaire 《Open Journal of Medical Imaging》 2015年第3期150-158,共9页
Background: In order to detect possible abnormalities of the spine posture of an individual patient, it is mandatory to dispose of adequate reference values based on measurements in a normal, symptom-free population. ... Background: In order to detect possible abnormalities of the spine posture of an individual patient, it is mandatory to dispose of adequate reference values based on measurements in a normal, symptom-free population. The Diers formetric?system allows for non-invasive and accurate assessment of the vertebral column based on the registration of external aspect of the back surface using the Moiré principle. Objective: To create a qualitative spine profile based on the percentile ranking of measurements obtained by the Diers formetric system taking into account possible confounding factors. Materials and Methods: Statistical analysis of formetric recordings in 216 symptom-free volunteers. Results: Maximal kyphotic angle, maximal scoliotic angle, sagittal imbalance, flèche cervicale, and pelvic inclination are significantly influenced by gender and by body mass index (BMI). A synoptic chart was created presenting the percentile ranking taking into account gender and BMI. The percentile ranking was summarized in both a table with colour code and depicted in a histogram of the individual’s Qualitative Spine Profile (QSP). Clinical Significance: Percentile ranking and the Quantitative Spine Profile taking into account gender and BMI should permit a more precise and reliable assessment of possible posture deviations related to the patient’s complaints, and may assist the therapist in selecting the best mode of treatment. 展开更多
关键词 Diers Formetric System SPINE reference Values KYPHOSIS LORDOSIS SAGITTAL IMBALANCE Body Mass Index Back Pain OSTEOPATHY Quantitative SPINE Profile
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北京市延庆县耕地景观特征 被引量:12
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作者 杨晓艳 闫东浩 程锋 《资源科学》 CSSCI CSCD 北大核心 2005年第3期98-104,共7页
本文通过对不同耕地类型区的典型样区调查从较小尺度研究延庆县耕地景观特征。选用斑块面积、斑块周长、斑块密度、边界密度等指标来描述耕地景观的斑块特征;采用全部廊道占耕地景观面积的比例、廊道类型、各类型廊道的密度、各类型廊... 本文通过对不同耕地类型区的典型样区调查从较小尺度研究延庆县耕地景观特征。选用斑块面积、斑块周长、斑块密度、边界密度等指标来描述耕地景观的斑块特征;采用全部廊道占耕地景观面积的比例、廊道类型、各类型廊道的密度、各类型廊道网络的连通度、环状网络的环通度来表达耕地景观中的廊道特征。研究结果表明,延庆县耕地斑块规模较小、零碎,斑块不规整;景观破碎化程度比较严重;耕地景观被边界分割的程度比较高;景观粒度较小;上述情况在坡耕地区域尤为严重。廊道占耕地景观面积的比例大,廊道类型主要包括道路、沟渠,坡耕地区还包括田坎。道路的密度较大,但道路网络连通性和环通性差,为耕地生态系统中的物流和能流提供的连通的、可选择的线路比较少。沟渠密度较小,有的样区根本没有沟渠分布,其网络连通性更差,沟渠廊道体系不健全,耕地的灌溉保证程度和排洪能力比较低。坡耕地中田坎占地面积比较大,加剧了坡耕地景观中廊道占耕地面积比例大的程度。 展开更多
关键词
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The Explanation of the Michelson-Morley Experiment Results by Means Universal Frame of Reference
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作者 Karol Szostek Roman Szostek 《Journal of Modern Physics》 2017年第11期1868-1883,共16页
It is commonly thought that the Michelson-Morley experiment from 1887 and Kennedy-Thorndike experiment from 1932 demonstrated that the universal frame of reference (ether) does not exist and that the velocity of light... It is commonly thought that the Michelson-Morley experiment from 1887 and Kennedy-Thorndike experiment from 1932 demonstrated that the universal frame of reference (ether) does not exist and that the velocity of light in vacuum is absolutely constant. The analysis of this experiment led to the creation of the Special Theory of Relativity (STR). The article explains why Michelson-Morley and Kennedy-Thorndike experiments could not detect the universal frame of reference. In this article, a different transformation of time and position than the Lorentz transformation is derived on the basis of the geometric analysis of the Michelson-Morley and Kennedy-Thorndike experiments. The transformation is derived based on the assumption that the universal frame of reference (UFR) exists. UFR is a frame of reference in which the velocity of light is constant in every direction. In inertial frames of reference moving in the UFR, the velocity of light may be different. The article has derived the formula for relative speed and patterns for the maximum and minimum speed of light that can be measured in the inertial system. Finally, the anisotropy of the microwave background radiation has been explained by using the presented theory. According to the body kinematics model presented in this article, anisotropy of cosmic microwave background is the Doppler effect for observer moving in the UFR. 展开更多
关键词 Kinematics of Bodies UNIVERSAL Frame of reference COORDINATE and Time Transformation One-Way Speed of Light Anisotropy of COSMIC Microwave Background
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The Prospect of Application of Extractive Reference Substance of Chinese Herbal Medicines 被引量:14
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作者 Peishan Xie Shuangcheng Ma +3 位作者 Pengfei Tu Zhengtao Wang Erich Stoeger Daniel Bensky 《Chinese Medicine》 2013年第4期125-136,共12页
The emerging development of Extractive Reference Substance (ERS) is a methodology that meets the needs for quality control for Chinese Herbal Medicines (CHM) and respects the holistic viewpoint of Traditional Chinese ... The emerging development of Extractive Reference Substance (ERS) is a methodology that meets the needs for quality control for Chinese Herbal Medicines (CHM) and respects the holistic viewpoint of Traditional Chinese Medicine (TCM) and its clinical use of multiple ingredients with synergistic effects. The convention of using just a selected few Chemical Reference Substances (CRS) cannot adequately assess the quality of intact CHM. A validated chemical spectrum of an ERS provides the global characteristics in order to more specifically identify and assess targeted CHM. This paper describes the fundamental concepts, potential significance, and basic criteria of ERS, along with methods of preparation and calibration. Given the diversity of CHM, the various problems that will occur in establishing the proper process of ERS will need to be solved in a step by step manner. The ERSs of Ziziphi spinosae semen and ERS of Fritillaria thunbergii bulbus are given as examples of the development of ERS and demonstrate why we are optimistic about the utility of this approach. 展开更多
关键词 Extractive reference Substance (ERS) Chinese HERBAL MEDICINE (CHM) ERS R & D Strategy HOLISTIC Quality Control
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Noise cancellation of a multi-reference full-wave magnetic resonance sounding signal based on a modified sigmoid variable step size least mean square algorithm 被引量:1
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作者 田宝凤 周媛媛 +2 位作者 朱慧 蒋川东 易晓峰 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第4期900-911,共12页
Nano-volt magnetic resonance sounding(MRS) signals are sufficiently weak so that during the actual measurement, they are affected by environmental electromagnetic noise, leading to inaccuracy of the extracted characte... Nano-volt magnetic resonance sounding(MRS) signals are sufficiently weak so that during the actual measurement, they are affected by environmental electromagnetic noise, leading to inaccuracy of the extracted characteristic parameters and hindering effective inverse interpretation. Considering the complexity and non-homogeneous spatial distribution of environmental noise and based on the theory of adaptive noise cancellation, a model system for noise cancellation using multi-reference coils was constructed to receive MRS signals. The feasibility of this system with theoretical calculation and experiments was analyzed and a modified sigmoid variable step size least mean square(SVSLMS) algorithm for noise cancellation was presented. The simulation results show that, the multi-reference coil method performs better than the single one on both signal-to-noise ratio(SNR) improvement and signal waveform optimization after filtering, under the condition of different noise correlations in the reference coils and primary detecting coils and different SNRs. In particular, when the noise correlation is poor and the SNR<0, the SNR can be improved by more than 8 dB after filtering with multi-reference coils. And the average fitting errors for initial amplitude and relaxation time are within 5%. Compared with the normalized least mean square(NLMS) algorithm and multichannel Wiener filter and processing field test data, the effectiveness of the proposed method is verified. 展开更多
关键词 magnetic resonance SOUNDING SIGNAL MULTI-reference coils adaptive noise CANCELLATION SIGMOID variable step size least mean SQUARE (SVSLMS)
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Absorbed Dose to Water Rate in a Cyberknife VSI System Reference Field Using Ionization Chambers and Gafchromic Films
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作者 Guerda Massillon-JL Nestor Aragó +4 位作者 n-Martí nez Arnulfo Gó mez-Muñ oz 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2017年第1期80-92,共13页
This work investigated the absorbed dose to water rate under reference conditions in a Cyberknife VSI system using radiochromic films EBT3 and MD-V3 and three ionization chambers: an Exradin A12 and two FC65P Welh&... This work investigated the absorbed dose to water rate under reference conditions in a Cyberknife VSI system using radiochromic films EBT3 and MD-V3 and three ionization chambers: an Exradin A12 and two FC65P Welh&ouml;fer Scanditronix with different serial numbers. The correction factor,, was studied using a Varian iX linac and the Cyberknife system. The measurements in the Varian iX were performed in a 10 × 10 cm2 field, 10 cm depth in liquid water at 90 cm and 70 cm SSD and in a 5.4 × 5.4 cm2 field, 10 cm depth at 70 cm SSD to simulate the Cyberknife conditions. In the Cyberknife system, measurements were performed using ionization chambers and both film types at 70 cm SSD and 10 cm depth in its 6 cm diameter reference field. The results indicate that ?is independent of the dosimeters and the evaluation methods. Maximum differences of 0.22% - 0.55% (combined uncertainties of 1.22% - 1.98%, k = 1) are obtained on ?using Varian iX, whereas discrepancies of 2.08% - 2.09% (combined uncertainties of 1.87% - 2.13%, k = 1) are observed using the Cyberknife system. Given the agreement between detectors and the combined standard uncertainties, the data from Varian iX could be considered the most accurate and consequently a weighted average factor of 0.902 ± 0.006 could be used for the Cyberknife VSI system reference field. Within measurement uncertainties, the absorbed dose rate measured in the Cyberknife VSI system reference field was found to be independent of the dosimeters used. These results suggest that the absorbed dose measured at a point within a given field size should be the same, regardless the dosimeter used, if their dosimetric characteristics are well known. This highlighted the importance of performing dosimetry by controlling all parameters that could affect the dosimeter response. One can conclude that radiochromic film dosimetry can be considered as an appropriate alternative for measuring absorbed dose to water rate. 展开更多
关键词 Small FIELD DOSIMETRY reference FIELD CYBERKNIFE Gafchromic Films Ionization CHAMBERS Dose RATE EBT3 MD-V3 6 MV X-Rays
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四种参考作物蒸散量综合法的比较 被引量:16
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作者 曹金峰 李玉中 +2 位作者 刘晓英 钟秀丽 赵叶萌 《中国农业气象》 CSCD 北大核心 2015年第4期428-436,共9页
参考作物蒸散量(ET0)的估算是作物需水量计算的关键,诸多估算方法在不同地区具有不同的适应性。本文利用中国农业主产区6个代表站点的气象数据,以FAO 56 Penman-Monteith(PM)为标准,对常用的1963 Penman(Pen63)、FAO 1979 Penman(FAO 79... 参考作物蒸散量(ET0)的估算是作物需水量计算的关键,诸多估算方法在不同地区具有不同的适应性。本文利用中国农业主产区6个代表站点的气象数据,以FAO 56 Penman-Monteith(PM)为标准,对常用的1963 Penman(Pen63)、FAO 1979 Penman(FAO 79)、FAO 24 Penman(FAO 24)及1996Kimberly Penman(Kpen)共4种参考作物蒸散量综合方法进行比较评价。结果表明:(1)Pen63、FAO 79及Kpen的日估算值均比PM估算值偏高,FAO 24偏低,其平均偏差分别为0.28、0.52、0和-0.17mm?d-1,相对偏差为16.0%、25.2%、2.4%、-5.3%,相对均方根误差为12.1%、22.4%、14.2%和13.5%。(2)Pen63、FAO79的月估算值显著高于PM值,在高估最大的5月份平均偏高12.5mm(10.8%)和28.2mm(22.6%)。FAO24表现为低估,低估最大的月份平均偏低11.4mm(8.1%),但在南方站点多数月份的估算值与PM估算值无显著差异。Kpen月估算值与PM估算值相比,既有高估(5-10月),也有低估,高估最大的月份平均偏高19.7mm(14.5%),且在南方站点的秋冬季有近6个月与PM无显著差异。(3)Pen63和FAO79的年值均显著大于PM年值,平均偏高103.8mm(11.8%)和191.5mm(21.3%)。FAO24年平均低估PM值60.9mm(6.3%),Kpen则平均高估50.5mm(5.8%)。(4)时间尺度对评价结果具有一定影响,4种综合法依据日、年值的评价效果排序分别为Pen63>FAO24>Kpen>FAO79和Kpen>FAO24>Pen63>FAO79。在日尺度下4种方法更适于湿润气候,但年尺度下仅FAO79和FAO24较适于湿润气候。可见,4种综合法以Pen63普适性最好,FAO79最低,因此使用FAO79前对其进行适应性评价尤为重要。 展开更多
关键词 (E T0) F A O 7 9 P e N M a N P e N M a n-M O N t e i t h F A O 2 4 K i M b e r l y P e N M a N
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Comparison study on measurement of rail weld joint between inertial reference method and multi-point chord reference method
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作者 Yifan Shi Yuan Wang +1 位作者 Xiaozhou Liu Ping Wang 《Railway Sciences》 2024年第1期69-83,共15页
Purpose – Straightness measurement of rail weld joint is of essential importance to railway maintenance. Dueto the lack of efficient measurement equipment, there has been limited in-depth research on rail weld joint ... Purpose – Straightness measurement of rail weld joint is of essential importance to railway maintenance. Dueto the lack of efficient measurement equipment, there has been limited in-depth research on rail weld joint with a5-m wavelength range, leaving a significant knowledge gap in this field.Design/methodology/approach – In this study, the authors used the well-established inertial referencemethod (IR-method), and the state-of-the-art multi-point chord reference method (MCR-method). Two methodshave been applied in different types of rail straightness measurement trollies, respectively. These instrumentswere tested in a high-speed rail section within a certain region of China. The test results were ultimatelyvalidated through using traditional straightedge and feeler gauge methods as reference data to evaluate the railweld joint straightness within the 5-m wavelength range.Findings – The research reveals that IR-method and MCR-method produce reasonably similar measurementresults for wavelengths below 1 m. However, MCR-method outperforms IR-method in terms of accuracy forwavelengths exceeding 3 m. Furthermore, it was observed that IR-method, while operating at a slower speed,carries the risk of derailing and is incapable of detecting rail weld joints and low joints within the track.Originality/value – The research compare two methods’ measurement effects in a longer wavelength rangeand demonstrate the superiority of MCR-method. 展开更多
关键词 Rail weld joint Inertial reference method Short-wavelength irregularities Multi-point chord reference method 5-m wavelength range
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Review of Two Years of Surgical Activities of the General Surgery Department of the Reference Health Center of Commune I of Bamako Mali
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作者 Tounkara Cheickna Cisse Amadou Beydi +5 位作者 Samake Hamidou Diarra Issaka Sanogo Modibo Diarra Bogoba Doumbia Seydou Yena Sadio 《Surgical Science》 2024年第4期195-206,共12页
The objectives of this work were to evaluate the surgical activities carried out in the general surgery department of the Reference Health Center of Commune I of Bamako, to describe the sociodemographic characteristic... The objectives of this work were to evaluate the surgical activities carried out in the general surgery department of the Reference Health Center of Commune I of Bamako, to describe the sociodemographic characteristics of the operated patients, to determine the main pathologies encountered and to evaluate qualitatively the result of the treatment. In order to improve performance, and the quality of care, and to identify common pathologies in the surgical department, we undertook a retrospective study on surgical activities from January 2009 to December 2010. At the end of this study, out of 474 men and 187 women (equal sex ratio 2.53);we were able to determine the frequency of surgical pathologies. Farmers, housewives and pupils/students were the most represented with 25.9% respectively;20% and 13.3%. The most frequently observed pathologies were wall hernia (44.8%), prostate adenoma (12%) and acute appendicitis (10.5%). The average length of hospitalization was 3.43 days. Infectious complications affected 25 patients (3.8% of cases) and a death rate of 0.45% (i.e. 3 patients). The average cost of care was 53,500 FCFA. Indeed, the reality of surgical practice in health centers was not the same because of the level of skills of practicing surgeons. 展开更多
关键词 Assessment Surgical Activities 2 Years reference Health Center of Commune I BAMAKO
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筛选啤酒酵母的标准培养基研究 被引量:3
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作者 王德良 孙君社 +2 位作者 宋绪磊 张五九 冯景章 《食品与发酵工业》 CAS CSCD 北大核心 2005年第3期78-82,共5页
通过以大生产麦汁成分的含量作为参考,如氨基酸的种类、含量,各种可发酵性糖的种类、含量,以及通过查阅大量文献资料了解酵母培养所需的一些必需组分,以此为基础,研制标准培养基的配料单,并结合与大生产麦汁做发酵性能测试,测试指标包... 通过以大生产麦汁成分的含量作为参考,如氨基酸的种类、含量,各种可发酵性糖的种类、含量,以及通过查阅大量文献资料了解酵母培养所需的一些必需组分,以此为基础,研制标准培养基的配料单,并结合与大生产麦汁做发酵性能测试,测试指标包括降糖速度、风味组分、还原双乙酰等指标,最终确定合理的配方;并验证其发酵性能的稳定与重复性;试验结果表明,配制培养基与大生产麦汁的各项发酵性能与指标接近,而且具有较好的重复与稳定性。可以用于酵母筛选,从而确定筛选优良酵母菌种的客观性。 展开更多
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A Reference Vector-Assisted Many-Objective Optimization Algorithm with Adaptive Niche Dominance Relation
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作者 Fangzhen Ge Yating Wu +1 位作者 Debao Chen Longfeng Shen 《Intelligent Automation & Soft Computing》 2024年第2期189-211,共23页
It is still a huge challenge for traditional Pareto-dominatedmany-objective optimization algorithms to solve manyobjective optimization problems because these algorithms hardly maintain the balance between convergence... It is still a huge challenge for traditional Pareto-dominatedmany-objective optimization algorithms to solve manyobjective optimization problems because these algorithms hardly maintain the balance between convergence and diversity and can only find a group of solutions focused on a small area on the Pareto front,resulting in poor performance of those algorithms.For this reason,we propose a reference vector-assisted algorithmwith an adaptive niche dominance relation,for short MaOEA-AR.The new dominance relation forms a niche based on the angle between candidate solutions.By comparing these solutions,the solutionwith the best convergence is found to be the non-dominated solution to improve the selection pressure.In reproduction,a mutation strategy of k-bit crossover and hybrid mutation is used to generate high-quality offspring.On 23 test problems with up to 15-objective,we compared the proposed algorithm with five state-of-the-art algorithms.The experimental results verified that the proposed algorithm is competitive. 展开更多
关键词 Many-objective optimization evolutionary algorithm Pareto dominance reference vector adaptive niche
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Evaluation of the Dietary Reference Intakes for Japanese (2010 Edition): Recommended Protein, Pantothenic acid, Vitamin D, and Iron Intakes for Breast-Fed Infants Aged 6 - 11 Months 被引量:1
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作者 Setsuko Tsutie Nobutaka Kurihara +3 位作者 Aki Sasaki Arisa Takagi Harumiti Seguti Tetsuya Inatome 《Food and Nutrition Sciences》 2011年第4期272-280,共9页
Objective: With regard to the 2010 edition of Dietary Reference Intakes for Japanese (DRIs-2010), we investigated whether the DRIs for two age groups, breast-fed infants aged 6-8 and 9-11 months, can be fulfilled for ... Objective: With regard to the 2010 edition of Dietary Reference Intakes for Japanese (DRIs-2010), we investigated whether the DRIs for two age groups, breast-fed infants aged 6-8 and 9-11 months, can be fulfilled for every nutrient in actual dietary practice. Design: We evaluated (1) whether the DRIs for all nutrients can be fulfilled in a formula with energy and protein exceeding their DRIs, (2) whether the DRIs for all nutrients can be fulfilled in a formula prepared in accordance with Japanese government-recommended weaning guidelines, and (3) what kinds of formulas can be prepared if the DRIs for all nutrients are fulfilled without referring to the weaning guidelines. Setting: Simulation of diet menu on the basis of published data in our university and survey of diet menu in a university hospital attached to a national medical school. Subjects: The three types of formulas were planned for ten days. Results: It was impossible to simultaneously fulfil the DRIs for 6 - 8-month-old infants concerning pantothenic acid, vitamin D, and iron and those for 9 - 11-month-old infants concerning these nutrients plus protein. Conclusion: According to the DRIs-2010, the DRI for all nutrients could not be fulfilled in an ingestible formula. 展开更多
关键词 Dietary reference INTAKES Breast-Fed INFANTS (6 - 11-Month-Old) Pantothenic Acid PROTEIN Vitamin D Iron
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Certification and uncertainty evaluation of flavonoids certified reference materials 被引量:1
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作者 Can Quan Huanfang Yao Caixia Hou 《Agricultural Sciences》 2013年第9期89-96,共8页
Flavonoids are the most widely used in the field of the food, medicine, and cosmetic due to their pharmacological functions and biological activities, such as anti-tumor, anti-inflammatory and antioxidation. This work... Flavonoids are the most widely used in the field of the food, medicine, and cosmetic due to their pharmacological functions and biological activities, such as anti-tumor, anti-inflammatory and antioxidation. This work described the assignment of purity values to 3 flavonoids certified reference materials (CRMs) including baicalein, 5,7-dihydoxy flavones and naringenine which?were developed in this study according to the ISO Guides 34 and 35. The qualitative analysis was performed by liquid chromatography-mass spectrometry (LC-MS) and infrared spectroscopy (IR). The CRMs’ purity values were assigned based on the weighted average of quantitative nuclear magnetic resonance method and mass balance approach with high resolution liquid chromatography-VWD. All the three CRMs with following value mass fractions: baicalein at a certified purity P ± U (k = 2) of 98.8% ± 0.8%;5,7-dihydoxy flavones of 99.1% ± 0.7% and naringenine of 99.5% ± 1.0% respectively. The homogeneity of the CRMs was determined by an in-house validated liquid chromatographic method. Potential degradation during storage was also investigated and a shelf-life based on this value was established. 展开更多
关键词 FLAVONOIDS Certified reference Material (CRM) QUANTITATIVE NUCLEAR Magnetic RESONANCE (QNMR) Mass BALANCE approach Uncertainty
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