开发基于Matlab的Stand-Alone软件

Matlab语言是国际上使用最为广泛的科学与工程计算软件工具,但是由Matlab生成的代码不能脱离Matlab环境运行。如何令Matlab代码能够完全脱离Matlab环境独立运行,对于各专业人员借助Matlab语言快速开发出具备强大计算功能的专业应用软件具有重要的意义。本文在分析了Matlab软件的优缺点的基础上,给出了使包含Matlab代码的应用软件能够脱离Matlab环境运行的具体步骤和方法。

A Case Study to Determine Optimal Capacity of a Stand-Alone Wind/PV/Battery System

In this paper, a stand-alone hybrid microgrid consisting of wind turbines, photovoltaic (PV) arrays and storage battery banks is developed for use in Qinghai Province, China. With the help of Software Homer and Matlab, different variables such as annual average wind speed, annual average load demand, and annual capacity shortage are considered. The net present value is then used during an entire project lifetime for the optimization solution.

Jaya Learning-Based Optimization for Optimal Sizing of Stand-Alone Photovoltaic,Wind Turbine,and Battery Systems

Renewable energy sources(RESs)are considered to be reliable and green electric power generation sources.Photovoltaics(PVs)and wind turbines(WTs)are used to provide electricity in remote areas.Optimal sizing of hybrid RESs is a vital challenge in a stand-alone environment.The meta-heuristic algorithms proposed in the past are dependent on algorithm-specific parameters for achieving an optimal solution.This paper proposes a hybrid algorithm of Jaya and a teaching–learning-based optimization(TLBO)named the JLBO algorithm for the optimal unit sizing of a PV–WT–battery hybrid system to satisfy the consumer’s load at minimal total annual cost(TAC).The reliability of the system is considered by a maximum allowable loss of power supply probability(LPSPmax)concept.The results obtained from the JLBO algorithm are compared with the original Jaya,TLBO,and genetic algorithms.The JLBO results show superior performance in terms of TAC,and the PV–WT–battery hybrid system is found to be the most economical scenario.This system provides a cost-effective solution for all proposed LPSPmax values as compared with PV–battery and WT–battery systems.

Optimal Configuration for Design of Stand-Alone PV System

This paper presents a design for a stand-alone photovoltaic (PV) system to provide the required electricity for a single residential household in rural area in Jordan. The complete design steps for the suggested household loads are carried out. Site radiation data and the electrical load data of a typical household in the considered site are taken into account during the design steps. The reliability of the system is quantified by the loss of load probability. A computer program is developed to simulate the PV system behavior and to numerically find an optimal combination of PV array and battery bank for the design of stand-alone photovoltaic systems in terms of reliability and costs. The program calculates life cycle cost and annualized unit electrical cost. Simulations results showed that a value of loss of load probability LLP can be met by several combinations of PV array and battery storage. The method developed here uniquely determines the optimum configuration that meets the load demand with the minimum cost. The difference between the costs of these combinations is very large. The optimal unit electrical cost of 1 kWh for LLP = 0.049 is $0.293;while for LLP 0.0027 it is $0.402. The results of the study encouraged the use of the PV systems to electrify the remote sites in Jordan.

Stand-alone XLIF治疗退变性脊柱侧凸

目的评估Stand-alone XLIF(即不使用螺钉内固定的单纯极外侧入路椎间融合术)治疗退变性脊柱侧凸(DS)的临床疗效。方法回顾性分析南部战区总医院采用Stand-alone XLIF治疗的15例DS患者的临床资料,其中单节段8例、双节段4例、三节段1例、四节段2例,共27个节段。采用腰椎Oswestry功能障碍指数(ODI)、日本骨科学会(JOA)评分和腰腿痛视觉模拟量表(VAS)评分评估患者的临床疗效;测量术前和末次随访时腰椎冠状面Cobb角和椎间孔高度,观察随访期间植骨融合及并发症发生情况。结果随访时间1~9年,平均随访时间4.2年。末次随访时腰椎ODI、JOA评分和VAS评分均较术前改善(P<0.05),术前、末次随访腰椎冠状面Cobb角和椎间孔高度分别为(28.1±5.8)°、(11.7±3.6)°和(16.3±2.5)、(19.2±2.7)mm,手术前后比较,差异有统计学意义(P<0.05)。术后1年24个节段(89%)获植骨融合,3个节段植骨延迟愈合。术后4例出现腹胀,5例出现腹股沟区一过性麻木或疼痛。随访期间未有内固定松动、感染并发症发生。结论在合理选择适应证的前提下,Stand-alone XLIF具有微创、术后恢复快的优势,可有效治疗DS。

A Summary of Optimal Methods for the Planning of Stand-alone Microgrid System

This paper describes the characteristics and optimal methods for the planning of stand-alone microgrid system, in order to improve the power supply reliability, increase the coefficient of utilization of renewable energy and reduce the cost of investment and operation. Next, the problems in the optimal planning for a stand-alone microgrid system are summarized, including the unique operational control targets, the flexible combination approaches and the operation strategies of distributed generation energy supply system, and the special requirements of the reliability of power supply quality factor from the different users. And then, centering on the operational control and the advanced energy management strategy, the optimal mathematical models and the solving methods, the reliability assessment approaches and the improvement measures of a stand-alone microgrid system, an overview of the general situation of the recent research at home and abroad and the limitations of the study are summarized. Finally, several problems, existing in the optimal planning of stand-alone microgrid system, to be urgently solved, are put forward.

Modeling and Simulation of a Hybrid Energy Storage System for Residential Grid-Tied Solar Microgrid Systems

Present-day power conversion and conditioning systems focus on transferring energy from a single type of power source into a single type of load or energy storage system (ESS). While these systems can be optimized within their specific topology (e.g. MPPT for solar applications and BMS for batteries), the topologies are not easily adapted to accept a wide range of power flow operating conditions. With a hybrid approach to energy storage and power flow, a system can be designed to operate at its most advantageous point, given the operating conditions. Based on the load demand, the system can select the optimal power source and ESS. This paper will investigate the feasibility of combining two types of power sources (main utility grid and photovoltaics (PV)) along with two types of ESS (ultra-capacitors and batteries). The simulation results will show the impact of a hybrid ESS on a grid-tied residential microgrid system performance under various operating scenarios.

Step-Loading Characteristics of Gas Engine Cogeneration System Using Doubly-Fed Induction Generator in Stand-Alone Operation

Application of a DFIG （doubly-fed induction generator）, which is one of adjustable speed generators, to a gas engine cogeneration system has been investigated. To operate during a blackout as an emergency power supply is one of important roles for the gas engine eogeneration system. In the case of conventional constant speed of synchronous generator, the amount of the allowed step load is limited to around 30% of the rated power. On the other hand, DFIG is expected to increase the amount of step load during the stand-alone operation. In this paper, it has been demonstrated that an increase in the gas engine speed resulted in an increase in the maximum amount of step load using experimental equipment with a real gas engine. It has been concluded that the proposed system can improve the performance of an emergency power supply at step-loading.

Stand-Alone Wind Power System Operating with Different Storage Structures

This paper deals with control method related to a wind system operating in stand-alone applications. The stand-alone wind system is composed of three energy transfer subsystems： wind generator subsystem （wind turbine and electrical generator）, energy storage subsystem, respectively, specific local network subsystem （controlled loads）. This wind power system performs in the same time the maximization of wind energy conversion and the power balance between produced and required power. Three structures of the energy storage subsystem, based on buffer battery operation and/or capacitor voltage control, are discussed. The simulation results show that the proposed stand-alone wind power system ensures a good management of the local energy request. The design of the structures is analyzed in Matlab/Simulink environment, using PowerSim toolbox.

Stand-along OLIF植入3D打印解剖型融合器治疗退行性腰椎管狭窄症32例临床分析

目的分析无内固定单纯斜外侧入路椎间融合术(Stand-along OLIF)植入自制3D打印解剖型融合器(3D anatomical type Cage)治疗退变性腰椎管狭窄症(Degenerative lumber spinal stenosis,DLSS)的临床疗效.方法32例退变性腰椎管狭窄症患者均行Stand-along OLIF手术,并采用视觉评分表(VAS)、Oswestry功能障碍指数(oswestry disability index,ODI)、SF-36生活质量量化表评价临床疗效;术前、术后1周、术后3个月、术后6个月、术后12个月及末次随访对手术节段的前缘椎间隙高度(DH)、后缘椎间隙高度(VH)、椎间孔高度(FH)及宽度(FW)、椎管前后矢状径(APD)、椎管横截面积(CSA)等参数进行影像学对比.结果32例患者术后1周至末次随访VAS评分和ODI指数均显著降低,SF-36显著增高(P<0.05);术后1周至末次随访DH、VH、FH、FW、APD及CSA均显著提高(P<0.05).结论Stand-alone OLIF植入3D打印解剖型融合器治疗DLSS具有创伤小、术后康复快、有效改善患者临床症状的优势.

某医院大型医用设备单机数据的CT和MRI使用绩效分析

目的打通现有医院业务系统,获取单机大型医用设备的绩效数据,对比分析医院7台电子计算机断层扫描(computed tomography,CT)设备、7台磁共振成像(magnetic resonance imaging,MRI)设备的2020年指标数据。方法开发数据接口,打通业务系统,利用关键字段,获取单机大型医用设备的结构化数据;基于指标数据,运用SPSS 26.0进行正态性检验、独立样本t检验分析,对7台CT、7台MRI的指标数据进行统计学分析。结果2020年CT品牌成本收益率排名前3位分别为UCT510、SOMATOM、Edge258,MRI品牌成本收益率排名前3位分别为3.0T HDX TWINSP、1.5T HDX UPG、Creator1.5T,CT、MRI的成本收益率差异具有统计学意义(P<0.05)。结论研究运用信息技术手段,打通业务系统,实现了大型医用设备单机数据的精确快捷获取,并尝试从成本收益角度出发进行分析,追踪其使用情况和投资回收情况,一定程度上反映单机大型医用设备的绩效产出,如CT设备成本收益率更高,国产CT设备表现亮眼,为大型医用设备的更新配置提供了数据支撑。

Optimal planning of stand-alone microgrids incorporating reliability

This paper proposes a new method for the planning of stand-alone microgrids.By means of clustering techniques,possible operating scenarios are obtained considering the daily patterns of wind and load profiles.Then,an approximate analytical model for reliability evaluation of battery energy storage system is developed in terms of the diverse scenarios,along with multistate models for wind energy system and diesel generating system.An optimal planning model is further illustrated based on the scenarios and the reliability models,with the objective of minimizing the present values of the costs occurring within the project lifetime,and with the constraints of system operation and reliability.Finally,a typical stand-alone microgrid is studied to verify the efficiency of the proposed method.

Micro-perforated structures as stand-alone sound absorbers

1 Introduction Early attempts to create a sound absorber which would function without the involvement of any fibrous or porous damping material go far back to K. A. Veliszhanina, S. N. Rschevkin and others as was outlined in Ref. [1]. 30 years ago, D. Y. MAA[2] was first in proposing a practicable design concept and calculation model for Micro-Perforated Absorber （MPA） prototypes which still forms the basis for various applications. During the past 12 years the Fraunhofer IBP developed a whole family of MPA products in close cooperation with 8 or more industrial partners operating in a variety of widely differing market segments. Meanwhile a large number of MPA modules and surface elements have evolved from MAA＇s creative pioneer work. More and more ambitious acousticians have, more recently, caught on this attractive idea of employing absorbers made of non-fibrous, non-abrasive materials with non-polluting, almost closed and optically attractive surfaces. MPA structures have played an important part in a long-standing and on-going effort at IBP to establish novel Alternative Fibreless Absorber （ALFA） tools for a better noise control and acoustic comfort.

A Preliminary Assessment of Load Consumption and Solar Power Potential at Kota Belud,Sabah

This paper presents a detailed preliminary assessment of load consumption and solar power potential at the Eco-Tourism Centre of Liogu Ku Silou-Silou(EPLISSI),Kota Belud,Sabah.This initial investigation assessed the feasibility of an off-grid solar PV system at EPLISSI with a suitable solar panel system for project installation and commissioning purposes.Due to the absence of an electrical grid and power supply,no pre-existing electrical appliances could be found in EPLISSI.Hence,an excel-based software,the ESCoBox,was used to produce the load profiles.The input data for this software came from a list of required electrical appliances(LED lights,fans,and phone chargers)and the historical frequency of visitors to EPLISSI.Meanwhile,to assess the solar power potential at EPLISSI,an online simulator known as Global Solar Atlas version 2.3 or GSA 2.3 was used.As an input for the GSA 2.3,the initial solar panel system capacity was set for 0.5 kWp,and then an increment of 0.1 kWp was entered until specific criteria were met.The selection of the suitable size is made when the system can satisfy the daily total average load demand and a specific load fulfillment demand.As a result,it was found that the site requires a total average demand and a total peak demand of 4.60 and 11.87 kWh/day,respectively.From the GSA 2.3 generated report,an off-grid solar PV system with the capacity of 2.50 kWp solar PV can satisfy the daily total average load demand of this area,where the average PV energy output is within the range of between 7.74–9.80 kWh/day or an average of 8.72 kWh/day.In conclusion,this preliminary assessment indicates that installing an off-grid solar PV system in this area is possible.

A Sliding Mode Controller Based on Robust Model Reference Adaptive Proportional-integral Control for Stand-alone Three-phase Inverter

This paper proposes a sliding mode controller based on robust model reference adaptive proportional-integral(RMRA-PI)control for a stand-alone voltage source inverter(SA-VSI).The proposed controller has two control loops where the coefficients of PI controller are regulated by the adaptive sliding law.This method is used to regulate the output voltage of the inverter under different load conditions and uncertainty,and adapts the output to the reference model to reduce the total harmonic distortion(THD).In this paper,the stability of the proposed controller is proven by using Lyapunov's theory and Barbalet’s lemma.The proposed controller performs well in voltage regulation such as low THD under sudden load change and uncertainty.Also,the results of the proposed controller are compared with PI controller to show the effectiveness of the presented control system.

Control Strategy of Wind Turbine Based on Permanent Magnet Synchronous Generator and Energy Storage for Stand-Alone Systems

This paper investigates a variable speed wind turbine based on permanent magnet synchronous generator and a full-scale power converter in a stand-alone system.An energy storage system(ESS)including battery and fuel cell-electrolyzer combination is connected to the DC link of the full-scale power converter through the power electronics interface.Wind is the primary power source of the system,the battery and FC-electrolyzer combination is used as a backup and a long-term storage system to provide or absorb power in the stand-alone system,respectively.In this paper,a control strategy is proposed for the operation of this variable speed wind turbine in a stand-alone system,where the generator-side converter and the ESS operate together to meet the demand of the loads.This control strategy is competent for supporting the variation of the loads or wind speed and limiting the DC-link voltage of the full-scale power converter in a small range.A simulation model of a variable speed wind turbine in a stand-alone system is developed using the simulation tool of PSCAD/EMTDC.The dynamic performance of the stand-alone wind turbine system and the proposed control strategy is assessed and emphasized with the simulation results.

Performance Analysis of PV Energy System in Western Region of Saudi Arabia

The potential implementation of photovoltaic (PV) energy system in western region of Saudi Arabia was analyzed in this paper. HOMER (hybrid optimization model for electric renewable) software was used to perform the technical feasibility of the system. The feasibility of PV energy system was analyzed based on solar irradiances. Stand-alone PV systems with battery storage element will be evaluated and discussed. The analysis will be addressed to the impact of PV and battery storage on electric energy production.

COMPARISON OFEMA-SYNCHRONIZED AND STAND-ALONE SPEECH BASED ON SPEECH RECOGNITION

Synchronized acoustic-articulatory data is the basis of various applications,such as exploring the fundamental mechanisms of speech production,acoustic to articulatory inversion(AAI),and articulatory to acoustic mapping(AAM).Numerous studies have been conducted based on the synchronized ElectroMagnetic Articulograhy(EMA)data and acoustic data.Hence,it is necessary to make clear whether the EMA-synchronized speech and stand-alone speech are different,and if so,how it affects the performance of the applications that are based on synchronized acoustic-articulatory data.In this study,we compare the differences between EMA-synchronized speech and stand-alone speech from the aspect of speech recognition based on the data of a male speaker.It is found that:i)the general error rate of EMA-synchronized speech is much higher than that of stand-alone speech;ii)apical vowels and apical/blade consonants are more significantly affected by the presence of EMA coils;iii)parts of vowel and consonant tokens are confused with the sounds who use the same articulator or the articulators nearby,such as confusion among apical vowels and confusion among apical and blade consonants;iv)the confusion of labial tokens demonstrates a diverse pattern.

Relevance of the P ＆ O MPPT Technique in an Original PV-Powered Water Pumping Application

Many papers exploiting the various MPPT （maximum power point tracking） techniques in PV （photovoltaic） applications, from the simple to the most complicated, can be found in literature. However, these techniques may not always be easy to implement in industrial applications. The main challenge of this paper is to model and implement the P ＆ O （perturb and observe） algorithm in a low-cost PV-powered pumping system. To that end, a comparative investigation of the performance characteristics of the most popular MPPT methods, such as FOCV （fractional open circuit voltage）, FSCC （fractional short circuit current）, FLC （fuzzy logic control）, ANN （artificial neural network） and INC （incremental conductance） is presented. This analysis is helpful to highlight the relevance of the P ＆ O technique taking better account of complexity, difficulty of implementation and cost considerations in water pumping applications. The targeted PV-powered pumping system is based on a single-phase induction motor supplied by a three-phase inverter controlled by the DTC （direct torque control） technique. This stand-alone PV system is dedicated to water pumping, especially in rural areas that have no access to national grids but have sufficient amount of solar radiation. Simulation modeling （Matlab/Simulink） and experimental results are presented to demonstrate the relevance of the system.

Enhancing power generation via an adaptive neuro-fuzzy and backstepping maximum-power-point tracking approach for photovoltaic single-ended primary inductor converter system

The distinct characteristics of photovoltaic generators related to power and current present a complex problem in terms of opti-mizing their power output.To tackle this,maximum-power-point tracking techniques such as the adaptive neuro-fuzzy inference system are frequently utilized for their swift adaptability and reduced fluctuations.In addition,the backstepping controller is often selected to handle both linear and non-linear systems due to its exceptional reliability.The purpose of this research is to propose an innovative method that merges the adaptive neuro-fuzzy inference system and backstepping controller to refine the tracking of the optimal power point and to bolster the stability of the photovoltaic system in the face of unpredictable scenarios,such as those pre-sented by the Ropp irradiance examination,which utilizes a single-ended primary inductor converter as a stage for power electronics adaptation.Simulations conducted using MATLAB®/Simulink®demonstrate that the combination of adaptive neuro-fuzzy inference system and backstepping controller achieves an impressive efficiency of 99.6%and exhibits fast,robust,and accurate responses com-pared with other algorithms such as artificial neural networks combined with the backstepping controller and conventional perturb and observe algorithm.