检索结果-南通市图书馆

Hepatobiliary Surgery and Nutrition 2020年第4期9卷 543-545页

作者： Josephine Frohme frank Tacke Department of Hepatology&Gastroenterology CharitéUniversity Medicine BerlinBerlinGermany

Over the last decade,the global prevalence of nonalcoholic fatty liver disease(NAFLD)in both adults and children was rapidly increasing and has become the most common cause of chronic liver disease in many parts of the *** is predicted to become also the most frequent indication for liver transplantation by 2030 and fueling the rising incidence and prevalence of primary liver cancer in western countries(1,2).

关键词： liver prevalence NAFLD

Monitoring and evaluation of the water quality of the Lower Neches River, Texas, USA

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

water Science and Engineering 2024年第1期17卷 21-32页

作者： Qin Qian Mengjie He frank Sun Xinyu Liu Department of Civil and Environmental Engineering Lamar UniversityBeaumontTX 77710USA Department of Industry Engineering Lamar UniversityBeaumontTX 77710USA Department of Computer Science Lamar UniversityBeaumontTX 77710USA

Increasing bacteria levels in the Lower Neches River caused by Hurricane Harvey has been of a serious *** study is to analyze the historical water sampling measurements and real-time water quality data collected with wireless sensors to monitor and evaluate water quality under different hydrological and hydraulic *** statistical and Pearson correlation analysis on historical water samples determines that alkalinity,chloride,hardness,conductivity,and pH are highly correlated,and they decrease with increasing flow rate due to *** flow rate has positive correlations with Escherichia coli,total suspended solids,and turbidity,which demonstrates that runoff is one of the causes of the elevated bacteria and sediment loadings in the *** correlation between *** and turbidity indicates that turbidity greater than 45 nephelometric turbidity units in the Neches River can serve as a proxy for *** to indicate the bacterial outbreak.A series of statistical tools and an innovative two-layer data smoothing filter are developed to detect outliers,fill missing values,and filter spikes of the sensor *** correlation analysis on the sensor data illustrates that the elevated sediment/bacteria/algae in the river is either caused by the first flush rain and heavy rain events in December to March or practices of land use and land ***,utilizing sensor measurements along with rainfall and discharge data is recommended to monitor and evaluate water quality,then in turn to provide early alerts on water resources management decisions.

关键词： water quality Pearson correlation analysis Lower Neches River YSI wireless sensors Non-point pollution

OPTIMAL POLICY wITH A TOTAL ORDER QUANTITY COMMITMENT CONTRACT IN THE PRESENCE OF A SPOT MARKET

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Systems Science and Systems Engineering 2011年第1期20卷 25-42页

作者： wei ZHANG Youhua (frank) CHEN Zhongsheng HUA weili XUE School of Management University of Science and Technology of China Hefei China Department of Systems Engineering and Engineering Management The Chinese University of Hong Kong Shatin N. T. Hong Kong China Yurun Corp. Nanjing China

In this paper, the optimal policy is considered when the buyer faces two supply sources： one is the contract supplier from which the buyer orders over a specific contract period （say, a year） at a pre-agreed price, and the other is the spot market. However, when ordering from the contract supplier, the buyer must fulfill a pre-determined total order quantity, or the so-called definite total order quantity commitment, over the whole contract period. In other words, the commitment secures the buyer a fixed price but obliges him/her a total order quantity over the contract period. Although the spot market gives the buyer more flexibility in terms of order quantities, its prices are volatile. Such a combination of contract and spot procurements is often observed in practice. within the contract period, there are multiple sub-periods, during each of which the buyer reviews the inventory, issues an individual order, and uses the on-hand inventory to meet the random demand. Thus, in each （ordering） period, the buyer will weigh between the current known spot price （by procuring from the spot market） and a lower future price （by waiting while consuming the remaining commitment）. An optimal dual ordering policy is characterized for each period, depending on the on-hand inventory level, the spot price, and the remaining commitment quantity. The optimal policy in each period is also shown to be independent of the contract price. Through a numerical study, the inventory cost is demonstrated to be （1） insensitive to the contract price when the total commitment quantity is lower than the total expected demand over the contract period and （2） non-increasing in the variability of spot prices.

关键词： Total ordering quantity commitment (TOQC) spot market procurement policy

Spatially resolved investigation of flame particle interaction in a two dimensional model packed bed

在线全文

学校读者我要写书评

暂无评论

Particuology 2024年第2期85卷 167-185页

作者： Mohammadhassan Khodsiani Reza Namdar Fathollah Varnik frank Beyrau Benoit Fond Institute of Fluid Dynamics and Thermodynamics Universitaetsplatz 2Magdeburg39106Saxony-AnhaltGermany Interdisciplinary Centre for Advanced Materials Simulation(ICAMS) Ruhr-University BochumBochum44801Germany ONERA The French Aerospace Lab Department of AerodynamicsAeroelasticity and Acoustics(DAAA)Paris-Saclay UniversityMeudon92190France

This study investigates the interaction between a premixed methane-air flame and particles inside a model packed *** opacity of the spherical packed beds to visible light poses a major barrier to the implementation of highly resolved optical diagnostics,so that no detailed experimental data were so far available for the validation of numerical ***,a two-dimensional cylindrical packed bed design is set up,which enables direct line-of-sight optical measurements without loss of spatial reso-lution over the fluid region between the *** this study,the case of cold metallic cylindrical particles(T=377 K)relevant to start-up of a reactor is investigated using internal particle cooling,which also allows cylinder specific heat transfer rate measurements by differential temperature measurements on the coolant *** two dimensional assumption is first verified by measuring the inflow ve-locity and cylinder temperature profile along the *** imaging is then per-formed using a telecentric lens to observe the position and geometry of the two-dimensional flame front with respect to the surrounding cylinders without loss of ***,the cylinder-specific flame to cylinder heat transfer rates and cylinder surface temperature are *** the flame is closely surrounded by the three cooled cylinders,intense heat transfer is observed in this region corresponding to 25±2.5%of the flame thermal *** were stabilised at different positions depending on inflow velocity and equivalence ratio,and a direct correlation between flame to cylinder stand-off distance and the heat transfer rate normalised to the flame thermal power was found for both top and side ***,sidewall quenching distances to the curved cylinder surfaces were evaluated,and seem to be influenced by the presence of a warm recirculation zone behind the *** investigation provides fully resolved flame front position and heat tra

关键词： Packed beds Flame-particle interaction Optical diagnostics Sidewall quenching

Adaptive Uniform Performance Control of Strict-Feedback Nonlinear Systems with Time-Varying Control Gain

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

IEEE/CAA Journal of Automatica Sinica 2023年第2期10卷 451-461页

作者： Kai Zhao Changyun wen Yongduan Song frank L.Lewis IEEE the Department of Electrical and Computer Engineering National University of SingaporeSingapore 119077Singapore the School of Electrical and Electronic Engineering Nanyang Technological UniversitySingapore 639798Singapore the State Key Laboratory of Power Transmission Equipment&System Security and New Technology Chongqing Key Laboratory of Intelligent Unmanned SystemsSchool of AutomationChongqing UniversityChongqing 400044China the UTA Research Institute University of Texas at ArlingtonFort WorthTX 76118 USA

In this paper,we present a novel adaptive performance control approach for strict-feedback nonparametric systems with unknown time-varying control coefficients,which mainly includes the following ***,by introducing several key transformation functions and selecting the initial value of the time-varying scaling function,the symmetric prescribed performance with global and semi-global properties can be handled uniformly,without the need for control ***,to handle the problem of unknown time-varying control coefficient with an unknown sign,we propose an enhanced Nussbaum function(ENF)bearing some unique properties and characteristics,with which the complex stability analysis based on specific Nussbaum functions as commonly used is no longer ***,by utilizing the core-function information technique,the nonparametric uncertainties in the system are gracefully handled so that no approximator is ***,simulation results verify the effectiveness and benefits of the approach.

关键词： Adaptive control enhanced Nussbaum function(ENF) strict-feedback systems unified prescribed performance

Reinforcement learning for optimal tracking of large-scale systems with multitime scales

在线全文

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2023年第7期66卷 5-29页

作者： Jinna LI Hao NIE Tianyou CHAI frank L.LEwIS School of Information and Control Engineering Liaoning Petrochemical University State Key Laboratory of Synthetical Automation for Process Industries Northeastern University UTA Research Institute University of Texas at Arlington

This paper aims to solve an optimal tracking control(OTC) problem of large-scale systems with multitime scales and coupled subsystems using singular perturbation(SP) theory and reinforcement learning(RL) techniques. A considerable contribution of this paper is the development of a data-driven SP-based RL method for the OTC of unknown large-scale systems with multitime scales. To achieve this, a multitime scale tracking problem was decomposed into a linear quadratic tracker problem for slow subsystems and a dynamical game problem for fast subsystems using the SP theory. Then, the distributed composite feedback controllers were found using a distributed off-policy integral RL algorithm that uses only measured data from the system in real time. Thus, the operational index can follow its prescribed target value via an approximately optimal approach. Theoretical analysis and proof are presented to demonstrate that the sum of the performances of reduced-order subsystems is approximately equal to the performance of the original large-scale system. Finally, numerical and practical examples are provided to validate the effectiveness of the proposed method.

关键词： reinforcement learning singular perturbation multitime scales data-driven control

Evolution and application of in-seam drilling for gas drainage

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

International Journal of Mining Science and Technology 2013年第4期23卷 534-544页

作者： frank Hungerford Ting Ren Naj Aziz Drilling Division Valley Longwall International Pty Ltd. School of Civil Mining & Environmental Engineering University of Wollongong

The presence of seam gas in the form of methane or carbon dioxide presents a hazard to underground coal mining ***-seam drilling has been undertaken for the past three decades for gas drainage to reduce the risk of gas outburst and lower the concentrations of seam gas in the underground *** drilling practices have reflected the standards of the times and have evolved with the development of technology and equipment and the needs to provide a safe mining environment *** practice was to adapt equipment from other felds,with rotary drilling being the only form of drilling *** form of drainage allowed various levels of gas drainage coverage but with changing emphasis,research and development within the coal industry has created specifc equipment,technology and practices to accurately place in-seam boreholes to provide effcient and effective gas *** into gas content determination established a standard for the process and safe levels for mining operations to *** technology improved from the wire-line,single-shot Eastman survey instruments which was time-dependent on borehole depth to electronic instruments located in the drill string which transmitted accurate survey data to the drilling crew without time *** allowed improved directional control and increased drilling *** drilling technology has now been established as the industry standard to provide effective gas drainage *** was identifed as an additional beneft with directional drilling as it has the ability to provide exploration data from long *** ability of the technology to provide safe and reliable means to investigate the need for inrush protection and water drainage ahead of mining has been *** drilling technology has now been introduced to the Chinese coal industry for gas drainage through a practice of auditing,design,supply,training and ongoing ***

关键词： Gas outbursts In-seam drilling Gas drainage Directional drilling technology Gas content determination Geological exploration

Ion-pairing HPLC methods to determine EDTA and DTPA in small molecule and biological pharmaceutical formulations

在线全文

学校读者我要写书评

暂无评论

Journal of Pharmaceutical Analysis 2016年第3期6卷 150-156页

作者： George wang frank P. Tomasella Analytical and Bioanalytical Development Pharmaceutical Development Bristol-Myers Squibb Company New Brunswick NJ 08903 USA

Ion-pairing high-performance liquid chromatography-ultraviolet （HPLC-UV） methods were developed to determine two commonly used chelating agents, ethylenediaminetetraacetic acid （EDTA） in Abilify （a small molecule drug with aripiprazole as the active pharmaceutical ingredient） oral solution and die- thylenetriaminepentaacetic acid （DTPA） in Yervoy （a monoclonal antibody drug with ipilimumab as the active pharmaceutical ingredient） intravenous formulation. Since the analytes, EDTA and DTPA, do not contain chromophores, transition metal ions （Cu2＋, Fe3＋） which generate highly stable metallocom- plexes with the chelating agents were added into the sample preparation to enhance UV detection. The use of metallocomplexes with ion-pairing chromatography provides the ability to achieve the desired sensitivity and selectivity in the development of the method. Specifically, the sample preparation in- volving metallocomplex formation allowed sensitive UV detection. Copper was utilized for the de- termination of EDTA and iron was utilized for the determination of DTPA. In the case of EDTA, a gradient mobile phase separated the components of the formulation from the analyte. In the method for DTPA, the active drug substance, ipilimumab, was eluted in the void. In addition, the optimization of the concentration of the ion-pairing reagent was discussed as a means of enhancing the retention of the aminopolycarboxylic acids （APCAs） including EDTA and DTPA and the specificity of the method. The analytical method development was designed based on the chromatographic properties of the analytes, the nature of the sample matrix and the intended purpose of the method. Validation data were presented for the two methods. Finally, both methods were successfully utilized in determining the fate of the chelates.

关键词： EDTA DTPA Ion-pairing HPLC Aripiprazole Ipilimumab

No Home without Hormones: How Plant Hormones Control Legume Nodule Organogenesis

在线全文

学校读者我要写书评

暂无评论

Plant Communications 2020年第5期1卷 21-40页

作者： Jieshun Lin Manuel frank Dugald Reid Department of Molecular Biology and Genetics Aarhus UniversityAarhusDenmark

The establishment of symbiotic nitrogen fixation requires the coordination of both nodule development and infection *** the evolution of a variety of anatomical structures,nodule organs serve a common purpose in establishing a localized area that facilitates efficient nitrogen *** in all plant developmental processes,the establishment of a new nodule organ is regulated by plant *** nodule initiation,regulation of plant hormone signaling is one of the major targets of symbiotic *** review the role of major developmental hormones in the initiation of the nodule organ and argue that the manipulation of plant hormones is a key requirement for engineering nitrogen fixation in non-legumes as the basis for improved food security and sustainability.

关键词： nitrogen fixation symbiosis hormones nodule legume

RF/wireless-interconnect: The next wave of connectivity

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2011年第5期54卷 1026-1038页

作者： TAM Saiwang CHANG Mau-Chung frank Electrical Engineering Department University of California Los Angeles Los Angeles CA 90095 USA

In the era of the nanometer CMOS technology, due to stringent system requirements in power, performance and other fundamental physical limitations (such as mechanical reliability, thermal constraints, overall system form factor, etc.), future VLSI systems are relying more on ultra-high data rates (up to 100 Gbps/pin or 20 Tbps aggregate), scalable, re-configurable, highly compact and reliable interconnect fabric. To overcome such challenges, we first explore the use of multiband RF/wireless-interconnects which can communicate simultaneously through multiple frequency bands with low power signal transmission, reconfigurable bandwidth and excellent mechanical flexibility and reliability. we then review recent advances in RF/wireless-interconnect in four different potential application domains, which include network-on-chips (NoCs), 3-dimensional integrated circuit (3DIC), advanced memory interface and ultra-high speed contactless connectors. Based on those developments, we further propose the future research direction on future inter- and intra-VLSI interconnect system through the comparison of performance and the proper communication range for all three types of interconnects, including communication data throughput, range and power consumption (pJ/bit) among the RF/wireless-interconnects, the optical interconnects and traditional parallel repeated bus.

关键词： RF-interconnect wireless RF-interconnect network-on-chips multi-band 3-dimensional integrated circuit advanced memory interface wireless contactless connector