检索结果-南通市图书馆

Non-point source analysis of a railway bridge area using statistical method:Case study of a concrete road-bed

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2014年第6期26卷 1321-1324页

作者： Kyungik Gil Jiyeol im Department of Civil Engineering Seoul National University of Science and TechnologyNowon-gu Seoul 139-743 Korea School of Civil Environmental and Architectural Engineering Korea University Anam-Dong 5gaSeongbuk-Gu Seoul 163-701 Korea

in an effort to protect the quality of the water system, interest in non-point source pollution is increasing. Recently, studies of non-point sources pollution are continuing in relation to various land- use areas, but such studies have not been fully conducted in railway facility sites. Using monitoring data of railway bridge area with concrete road-bed, the runoff characteristics, pollutant unit loads, and first flush criteria were assessed. Railway bridge area with concrete road-bed typically show the first flush effect, and the pollutant unit load was determined to be higher than other public facilities areas. Further, the first flush criteria show an effective rainfall amount of 7 mm. in other words, from the runoff of railway facilities, considerable amounts of non-point source pollutants are occurred, indicating the need to create best management practices which are adequate for railway facility sites.

关键词： non-point source pollution railway concrete road-bed first flush criteria first flush effect

Self-phase modulation via similariton solutions of the perturbed NLSE Modulation instability and induced self-steepening

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2022年第8期74卷 41-50页

作者： h i Abdel-Gawad Department of Mathematics Faculty of Science Cairo University Egypt

The perturbed nonlinear Schrodinger equation(PNLSE)describes the pulse propagation in optical fibers,which results from the interaction of the higher-order dispersion effect,self-steepening(SS)and self-phase modulation(SPM).The challenge between these aforementioned phenomena may lead to a dominant one among *** is worth noticing that the study of modulation instability(Mi)leads to the inspection of dominant phenomena(DPh).indeed,the Mi triggers when the coefficient of DPh exceeds a critical value and it may occur that the interaction leads to wave *** PNLSE is currently studied in the literature,mainly on finding traveling wave ***,we are concerned with analyzing the similarity solutions of the *** exact solutions are obtained via introducing similarity transformations and by using the extended unified *** solutions are evaluated numerically and they are shown *** is observed that the intensity of the pulses exhibits self steepening which progresses to shock soliton in ultrashort time(or near t=0).Also,it is found that the real part of the solution exhibits self-phase modulation in *** study of(Mi)determines the critical value for the coefficients of SS,SPM,or high dispersivity to occur.

关键词： Perturbed NLSE steepening self–phase modulation extended unified method

市政排涝自吸泵启动过程气液两相流动及压力脉动分析

在线全文

学校读者我要写书评

暂无评论

江苏大学学报（自然科学版） 2020年第5期41卷 516-522页

作者：杨波潘中永 ibra FALL 江苏大学国家水泵及系统工程技术研究中心江苏镇江212013

为了探明自吸泵的自吸机理.以外混式自吸泵为研究对象,利用CFX仿真软件中的VOF(volume of fluid)两相流模型和k-ε湍流模型,并结合网格滑移技术进行自吸过程非稳态数值模拟,分析了不同时刻下泵内气液两相体积、液相速度、出口气体体积... 详细信息

为了探明自吸泵的自吸机理.以外混式自吸泵为研究对象,利用CFX仿真软件中的VOF(volume of fluid)两相流模型和k-ε湍流模型,并结合网格滑移技术进行自吸过程非稳态数值模拟,分析了不同时刻下泵内气液两相体积、液相速度、出口气体体积分数和压力的分布情况.同时改变非稳态模拟的时间步长及总时长,监测自吸过程叶轮及蜗壳内监测点的压力变化.结果表明:自吸泵的吸气与排气主要集中在启动过程的初期和中期,叶轮入口和泵出口的气体体积分数分别超过60%和75%;叶轮出口的气液混合带导致了叶轮出口到蜗壳内侧大片区域内的流动紊乱现象,降低了叶轮的做功能力,进而影响了泵的正常排气;叶轮监测点压力脉动幅值与距叶片工作面的大小有关,蜗壳内监测点压力脉动幅值与距叶轮外缘的大小有关.

关键词：自吸泵气液两相流非定常数值模拟压力脉动瞬时体积分数

improved rate-distortion optimized video coding using non-integer bit estimation and multiple Lambda search

在线全文

学校读者我要写书评

暂无评论

Frontiers of Computer Science 2016年第1期10卷 157-166页

作者： Sio Kei im Mohammad Mahdi GhANDi MPi-QMUL information Systems Research Centre Macao Polytechnic Institute Macao China Department of Electronic Systems Engineering University of Essex Colchestey CO4 3SQ UK

Many modern video encoders use the Lagrangian rate-distortion optimization （RDO） algorithm for mode deci- sions during the compression procedure. For each encoding stage, this approach involves minimizing a cost, which is a function of rate, distortion and a multiplier called Lambda. This paper proposes to improve the RDO process by applying two modifications. The first modification is to increase the ac- curacy of rate estimation, which is achieved by computing a non-integer number of bits for arithmetic coding of the syntax elements. This leads to a more accurate cost computation and therefore a better mode decision. The second modification is to search and adjust the value of Lambda based on the char- acteristics of each coding stage. For the encoder used, this paper proposes to search multiple values of Lambda for the intra-4x4 mode decision. Moreover, a simple shift in Lambda value is proposed for motion estimation. Each of these modi- fications offers a certain gain in RDO performance, and, when all are combined, an average bit-rate saving of up to 7.0% can be achieved for the h.264/AVC codec while the same concept is applicable to the h.265/hEVC codec as well. The extra added complexity is contained to a certain level, and is also adjustable according to the processing resources available.

关键词： rate distortion optimization Lambda adjust-ment non-integer bit estimation h.264/AVC h265/hEVCvideo coding

Biodegradation of p-cresol by aerobic granules in sequencing batch reactor

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2012年第11期24卷 2012-2027页

作者： Farrukh Basheer i.h.Farooqi Environmental Engineering Section Department of Civil EngineeringAligarh Muslim UniversityAligarh202002India

The cultivation of aerobic granules in sequencing batch reactor for the biodegradation of p-cresol was studied. The reactor was started with 100 mg/L of p-cresol. Aerobic granules first appeared within one month of start up. The granules were large and strong and had a compact structure. The diameter of stable granules was in the range of 1-5 mm. The integrity coefficient and granules density was found to be 96% and 1046 kg/m3, raspectively, The settling velocity of granules was found to be in the range of 2×10^-2-6×10^-7 m/sec. The aerobic granules were able to degrade p-cresol upto 800 mg/L at a removal efficiency of 88%. Specific p-cresol degradation rate in aerobic granules followed haldane model for substrate inhibition, high specific p-cresol degradation rate up to 0,96 g pcresol/（g ***） were sustained upto p-cresol concentration of 400 mg/L, higher removal efficiency, good settling characteristics of aerobic granules, makes sequencing batch reactor suitable for erLhaneing the microorganism potential for biodegradation of inhibitory compounds.

关键词： aerobic granules p-cresol sequencing batch reactor (SBR) haldane kinetics equation

Buoyant Marangoni convection of nanofluids in square cavity

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2015年第9期36卷 1169-1184页

作者： h.SALEh i.hAShim School of Mathematical Sciences Universiti Kebangsaan Malaysia Solar Energy Research institute Universiti Kebangsaan Malaysia Research institute Center for Modeling & Computer Simulation(RI/CM&CS)King Fahd University of Petroleum & Minerals

The buoyant Marangoni convection heat transfer in a differentially heated cavity is numerically studied. The cavity is filled with water-Ag, water-Cu, water-Al2O3, and water-TiO2 nanofiuids. The governing equations are based on the equations involving the stream function, vorticity, and temperature. The dimensionless forms of the governing equations are solved by the finite difference （FD） scheme consisting of the alternating direction implicit （ADi） method and the tri-diagonal matrix algorithm （TDMA）. it is found that the increase in the nanoparticle concentration leads to the decrease in the flow rates in the secondary cells when the convective thermocapillary and the buoyancy force have similar strength. A critical Marangoni number exists, below which increasing the Marangoni number decreases the average Nusselt number, and above which increasing the Marangoni number increases the average Nusselt number. The nanoparticles play a crucial role in the critical Marangoni number.

关键词： finite difference method Marangoni convection nanofluid

Key-Value Store Coupled with an Operating System for Storing Large-Scale Values

在线全文

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2022年第11期73卷 3333-3350页

作者： Jeonghwan im hyuk-Yoon Kwon Graduate School of Data Science Seoul National University of Science and TechnologySeoulKorea Department of industrial Engineering Graduate School of Data ScienceResearch Center for Electrical and Information ScienceSeoul National University of Science and TechnologySeoulKorea

The key-value store can provide flexibility of data types because it does not need to specify the data types to be stored in advance and can store any types of data as the value of the key-value *** types of studies have been conducted to improve the performance of the key-value store while maintaining its ***,the research efforts storing the large-scale values such as multimedia data files(e.g.,images or videos)in the key-value store were *** this study,we propose a new key-value store,WR-Store++aiming to store the large-scale values ***,it provides a new design of separating data and index by working with the built-in data structure of the Windows operating system and the file *** utilization of the built-in data structure of the Windows operating system achieves the efficiency of the key-value store and that of the file system extends the limited space of the storage *** also present chunk-based memory management and parallel processing of WR-Store++to further improve its performance in the GET *** the experiments,we show that WR-Store++can store at least 32.74 times larger datasets than the existing baseline key-value store,WR-Store,which has the limitation in storing large-scale data ***,in terms of processing efficiency,we show that WR-Store++outperforms not only WR-Store but also the other state-ofthe-art key-value stores,LevelDB,RocksDB,and BerkeleyDB,for individual key-value operations and mixed workloads.

关键词： Key-value stores large-scale values chunk-based memory management parallel processing

New method for calibration of sun photometers

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Optics Letters 2009年第9期7卷 760-763页

作者： h.h.Asadov i.G.Chobanzadeh Azerbaijan National Aerospace Agency

A new method for calibration of sun photometers based on Bouguer-Beer law is proposed. The developed basic equation of calibration makes it possible to formulate the derivative methods of calibration on the basis of p... 详细信息

关键词： New method for calibration of sun photometers 双入

Prognostic impact of inflammatory and nutritional biomarkers in pancreatic cancer

在线全文

学校读者我要写书评

暂无评论

World Journal of Clinical Oncology 2025年第1期16卷 5-9页

作者： Macarena Teja María i Garrido Abrahams Ocanto Felipe Counago Department of Radiation Oncology GenesisCare-San Francisco de Asís University HospitalMadrid 28002Spain Department of Radiation Oncology GenesisCare-Vithas La Milagrosa University HospitalMadrid 28010Spain National Director GenesisCare SpainMadrid 28043Spain Department of Medicine School of MedicineHealth and SportEuropean University of MadridMadrid 28670Spain

Pancreatic cancer is usually associated with a poor *** is the main curative treatment but pancreatic operations are aggressive and new tools that help clinicians to predict surgical and prognostic outcomes are *** et al recently published a retrospective,single centre cohort study evaluating the impact of seven nutritional and inflammatory markers in pancreatic cancer surgical patients:The albumin-to-globulin ratio,prognostic nutritional index(PNi),systemic immune-inflammation index(Sii),neutrophil-to-lymphocyte ratio(NLR),platelet-to-lymphocyte ratio(PLR),nutritional risk index,and the geriatric nutritional risk index.A significant correlation was found between the PNi,Sii,NLR,and PLR and a hospital discharge of less than 15 *** a univariable analysis,PNi,Sii,NLR and PLR were significantly related to recurrence-free survival and,in a multivariable analysis PNi was associated with overall *** meta-analyses corroborate the results in terms of prognosis but individual studies are discordant on their ***,the cut-off values for these markers vary significantly between studies and there are no clinical trials comparing them to identify the most relevant *** are limitations when implementing nutritional and inflammatory biomarkers into clinical practice and further studies are needed in order to answer these questions.

关键词： inflammatory biomarkers Nutritional biomarkers Pancreatic cancer Prognosis Surgical complications