Analysis of handoff in distributed mobile communications system based on remote antenna unit selection

A remote antenna unit （RAU） selection model is presented, and two kinds of handoffs, intra-cell handoff （HO） and inter-cell HO, are defined in distributed mobile communications systems （DAS）. After that, an inter-cell HO model is proposed, in which the average power of the active set （AS） is used to predict the position of the mobile station （MS）. The total power of the AS and the handoff set （HOS） are utilized to determine whether an inter-cell HO is necessary. Furthermore, the relationship between HO parameters and performance metrics is studied in detail based on RAU selection. Simulation results show that both the intra-cell HO and the inter-cell HO can achieve oerfect performance by aoprooriate settings of HO parameters.

Overview of fluoride distribution in major aquifer units of northern Nigeria

Symptoms of dental fluorosis such as mottled teeth are common among adults, youth and children in several rural communities in northern Nigeria. This has inspired the Authors to investigate the concentration of fluoride in the natural water systems of the major aquifer units (Basement, Sedimentary, Volcanic and Younger Granites) in some parts of northern Nigeria and to delineate areas of high risk of dental fluorosis, crippling skeletal fluorosis and dental caries. Six hundred and twenty seven analytical values for water were obtained from the literature and from analysis of samples from the major aquifer units of northern Nigeria: Basement-232, Sedimentary-328, Younger Granites-38 and Volcanic-28. Fluoride concentrations range from 0.03 to 10.30 mg/L in the Basement Aquifer;0.00 to 5.00 mg/L in the Sedimentary Aquifer;0.00 to 0.89 mg/L in the Younger Granites Aquifer;and 0.00 to 0.78 mg/L in the Volcanic Aquifer. A background value of 1.0 mg/L for fluoride concentration for northern Nigeria has been determined in this study. Areas identified with high fluoride in their waters above the World Health Organisation (WHO) recommended maximum permissible level in drinking water of 1.5 mg/L are: Dzuma, Dilchidima, Ngalbi, Udin, Kaltungo Biliri, Shongwom, Dass in the the northeast basement aquifers;Maiduguri, Mafa, Mobbar, Ngala, Logomani, Gombe in the northeast sedimentary aquifers: Langtang, Dorong, Furzi in the north-central basement aquifers and Pakoro in the northcentral sedimentary aquifers: Shawo and Barkin Lamba in the northwest basement aquifers. No anomalously high values of fluoride were recorded in the northwest sedimentary aquifers. All waters sampled in the Younger Granites and the Volcanic Aquifers have fluoride contents lower than the WHO recommended maximum permissible level in drinking water of 1.5 mg/L;and over ninety percent of the waters have fluoride concentration below the 0.5 mg/L recommended by WHO for the prevention of dental caries. Positive correlation between dental fluorosis and high fluoride water consumption has been established in all the areas with high fluoride in their waters. Positive correlation has also been established between genu valgum (bowing of legs) and consumption of high fluo-ride waters in Langtang Area. These data have been used to delineate areas of the Younger Granites Province and the Volcanic Province where inhabitants are at high risk of having dental caries.

A Remark on Pl Type Interpolation on Non-Uniformly Distributed Nodes on the Unit Circle

In this paper we study the problem of explicit representation and convergence of Pal type （0;1） interpolation and its converse, with some additional conditions, on the non-uniformly distributed nodes on the unit circle obtaIned by projecting the interlaced zeros of Pn （x） and Pn′ （x） on the unit circle. The motivation to this problem can be traced to the recent studies on the regularity of Birkhoff interpolation and Pal type interpolations on non-uniformly distributed zeros on the unit circle.

Designing a Protection Scheme in Micro-Grid Systems with DG Using Central Protection Unite and Multiple Setting Group Protection Relays

Distributed generators now is widely used in electrical power networks, in some cases it works seasonally, and some types works at special weather conditions like photo voltaic systems and wind energy, and due to this continuous changes in generation condition, the fault current level in network will be affected, this changes in fault current level will affect in the coordination between protection relays and to keep the coordination at right way, an adaptive protection system is required that can adaptive its setting according to generation changes, the fault current level in each case is evaluated using ETAP software, and the required relay setting in each case is also evaluated using Grey Wolf Optimizer (GWO) algorithm, and to select suitable setting which required in each condition, to select the active setting group of protection relay according to generation capacity, central protection unite can be used, and to improve protection stability and minimizing relays tripping time, a proposed method for selecting suitable backup relay is used, which leads to decrease relays tripping time and increase system stability, output settings for relays in all cases achieved our constrains.

The Prognostic Value of Red Cell Distribution Width in Critically Ill Cerebral Infarction Patients:A Retrospective Cohort Study

Objective:Red blood cell distribution width(RDW)has been utilized as a prognostic indicator for mortality risk assessment in cardiovascular and cerebrovascular patients.Nevertheless,the prognostic significance of RDW in critically ill patients with cerebral infarction is yet to be investigated.The objective of this study is to examine the association between RDW and the risk of all-cause mortality in cerebral infarction patients admitted to the intensive care unit(ICU).Method:A retrospective cohort study was conducted using the Medical Information Mart for Intensive Care IV 2.2(MIMIC-IV)intensive care dataset for data analysis.The main results were the all-cause mortality rates at 3 and 12 months of follow-up.Cumulative curves were plotted using the Kaplan-Meier method,and Cox proportional hazards analysis was used to examine the relationship between RDW and mortality rates in critically ill cerebral infarction patients.Results:The findings indicate that RDW serves as a significant prognostic factor for mortality risk in critically ill stroke patients,specifically at the 3 and 12-month follow-up periods.The observed correlation between increasing RDW levels and higher mortality rates among cerebral infarction patients further supports the potential utility of RDW as a predictive indicator.Conclusion:RDW emerges as an independent predictor of mortality risk during the 3 and 12-month follow-up periods for critically ill patients with cerebral infarction.

Stability analysis unit and spatial distribution pattern of the terrain texture in the northern Shaanxi Loess Plateau

Terrain texture analysis is an important method of digital terrain analysis in quantitative geomorphological research and in the exploration of the spatial heterogeneity and autocorrelation of terrain features. However, a major issue often neglected in previous studies is the calculation unit of the terrain texture, that is, the stability analysis unit. As the test size increases, the derived terrain textures become increasingly similar so that their differences can be ignored. The test size of terrain texture is defined as the stability analysis unit. This study randomly selected 48 areas within the Loess Plateau in northern Shaanxi in China as the study sites and used the gray level co-occurrence matrix to calculate the terrain texture. The stability analysis unit of the terrain texture was then extracted, and its spatial distribution pattern in the Loess Plateau was studiedusing spatial interpolation method. Four terrain texture metrics, i.e., homogeneity, energy, correlation, and contrast, were extracted on the basis of the stability analysis unit, and the spatial variation patterns of these parameters were studied. Results showed that the spatial distribution pattern and the terrain texture metrics reflected a trend of high–low–high from north to south, which correlated with the spatial distribution of the landforms at the Loess Plateau. In addition, the terrain texture measures was significantly correlated with the terrain factors of gully density and slope, and this relationship showed that terrain texture measures based on the stability analysis unit could reflect the basic characteristics of terrain morphology. The stability analysis unit provided a reasonable analytical scale for terrain texture analysis and could be used as a measure of the regional topography to accurately describe basic terrain characteristics.

Optimization of Minimum Power Output for Combined Heat and Power Units Considering Peak Load Regulation Ability

Northern China has rich wind power and photovoltaic renewable resources. Combined Heat and Power (CHP) Units to meet the load demand and limit its peaking capacity in winter, to a certain extent, it results in structural problems of wind-solar power and thermoelectric. To solve these problems, this paper proposes a plurality of units together to ensure supply of heat load on the premise, by building a thermoelectric power peaking considering thermal load unit group dynamic scheduling model, to achieve the potential of different thermoelectric properties peaking units of the excavation. Simulation examples show, if the unit group exists obvious relationship thermoelectric individual differences, the thermal load dynamic scheduling can be more significantly improved overall performance peaking unit group, effectively increase clean energy consumptive.

Establishing acceptance limits for uniformity of dosage units

Uniformity of dosage units[1]is one of the most commonly employed compendial tests to evaluate the dosage units.In the test,the acceptance value(AV)is the key statistics-based acceptance parameter with the limit of not more than 15 to measure the uniformity degree of the dosage units in terms of content uniformity or weight variation as applicable.With quality assurance(QA)principle,there should be some kinds of predetermined acceptance limits,like Bergum method introduced by James S.Bergum in 1990[2]and 2007[3]and recently recognized by ASTM 2709[4]and ASTM 2810[5]to ensure that the AV results for any future quality control(QC)samples will not exceed the compendial limit(NMT 15).

DISOPE distributed model predictive control of cascade systems with network communication

A novel distributed model predictive control scheme based on dynamic integrated system optimization and parameter estimation （DISOPE） was proposed for nonlinear cascade systems under network environment. Under the distributed control structure, online optimization of the cascade system was composed of several cascaded agents that can cooperate and exchange information via network communication. By iterating on modified distributed linear optimal control problems on the basis of estimating parameters at every iteration the correct optimal control action of the nonlinear model predictive control problem of the cascade system could be obtained, assuming that the algorithm was convergent. This approach avoids solving the complex nonlinear optimization problem and significantly reduces the computational burden. The simulation results of the fossil fuel power unit are illustrated to verify the effectiveness and practicability of the proposed algorithm.

Research on Test Data Distribution of Strapdown Inertial Measurement Unit Based on Bayesian Method

Aiming at that the successive test data set of the strapdown inertial measurement unit is always small,a Bayesian method is used to study its statistical characteristics.Its prior and posterior distributions are set up by the method and the pretest,sample and population information.Some statistical inferences can be made based on the posterior distribution.It can reduce the statistical analysis error in the case of small sample set.

Type selection and maintenance of the control system of large-scale air separation units

Based on the practice of Baosteel＇ s 60000 m3/h air separation unit （ASU） ,which is the first domestically- integrated unit of such a scale, this paper studies the principles of type selection of the distribution control system （DCS）. It discusses the design of the unit＇s control system,which involves a compressor system,a purification system （molecular sieving）, a turbo expansion system and an air separation system. The final part of the paper discusses the maintenance and future development of the ASU control system at Baosteel.

Impact of PV Distributed Generation on Loop Distribution Network

The rapid spreading of the Photovoltaic (PV) Systems as Distributed Generation (DG) in medium and low voltage networks created many effects and changes on the existing power system networks. In this work, two methods have been used and applied to determine the optimal allocation and sizing of the PV to be installed as DGs (ranging from 250 kW up to 3 MW). The first one is to determine the location according to the maximal power losses reduction over the feeder. The second one is by using the Harmony Search Algorithm which is claimed to be a powerful technique for optimal allocation of PV systems. The results of the two techniques were compared and found to be nearly closed. Furthermore, investigation on the effects on the feeder in terms of voltage levels, power factor readings, and short circuit current levels has been done. All calculations and simulations are conducted by using the MATLAB Simulation Program. Some field calculations and observations have been expended in order to substantiate the research findings and validation.

Realization of Distribution Network Feeder Terminal Unit based on Dual-DSP

This paper presents the design proposal of distribution network monitoring unit based on dual-DSP.A detailed description of the hardware structure about the device is introduced which including signal scheduling,SPI communication,the serial human-computer communication and network communication.Additionally,the paper describes the software process about the master and slave DSPs.Then the analog precision test and the protection response test are carried out.The result shows that the design proposal is correct.

某三级医院鲍曼不动杆菌临床分布及耐药性变迁

目的:分析川北医学院附属医院分离的鲍曼不动杆菌(AB)的临床分布及耐药情况,了解其变化趋势。方法:分析川北医学院附属医院分离的764株AB的临床分布及药敏试验结果,并与课题组前期研究结果进行对比分析。结果:本次检出的AB在各标本中及在临床科室的占比与川北医学院附属医院2004~2008年和2011~2014年报告数据存在统计学差异(P<0.05),三个时期均以痰标本检出率最高(73.1%~84.2%),ICU和神经外科占比位列前两位;近年急诊科的AB分离率高达17.3%。三个时期12种抗菌药的合计耐药率分别为69.2%、79.6%和58.1%(P<0.05)。2020~2021年,AB对所试13/16种抗菌药的耐药率均>50%。2020~2021年神经外科和ICU分离菌株对所试12种抗菌药的合计耐药率分别为66.5%和75.4%,较2011~2014年的耐药率(分别为79.7%和84.1%)降低(P<0.05)。结论:川北医学院附属医院AB主要见于呼吸道感染,以ICU、神经外科和急诊科较为常见。AB(尤其在ICU和神经外科病房)多重耐药现象较为严重。规范抗菌药物使用和加强细菌耐药性实时监测具有重要意义。

考虑负荷停电差异化的配电自动化终端混合优化配置方法

成本低且安装灵活的故障指示器(FI)常与具备远程遥控能力的馈线远程终端单元(FRTU)协同完成配电网的故障定位和隔离,以缩减负荷停电时间。在配电网各开关位置或分支线路上,有选择性地部署配电自动化终端的FRTU和FI,可减少故障停电损失费用。为此,提出了考虑各供电负荷停电差异化的FRTU和FI的混合优化配置新方法。首先,根据待分析负荷、故障点、上级110 kV/35 kV变电站以及联络开关的相对位置,考虑FRTU和FI协同作用下的故障定位、故障隔离和供电恢复全过程,建立基于FRTU和FI混合配置方案的各供电负荷差异化停电时间关系式。然后,构建了以FRTU和FI的全生命周期成本费用和故障停电损失费用之和最小为目标的混合优化配置数学模型,并完成优化求解。最后,在CSG 53节点测试系统上验证了所提方法的有效性。

超高层建筑综合体消防负荷供配电系统设计

结合现行国家、行业及地方规范、标准,对超高层建筑综合体的消防负荷供配电系统、柴油发电机选择等设计方法及设计要点进行详细探讨。

面向雷达分队指挥训练的分布式仿真系统架构研究

针对多雷达分队灵活的指挥训练需求,基于TCP/IP通信协议和两层配置文件,设计了面向多层服务的局域网模拟训练仿真系统架构,可实现模拟对象的在线随遇接入和数量上灵活扩展。详细介绍了多层服务设计思路和配置方法。

ICU感染病原菌分布情况及耐药性分析

目的:分析重症监护室(ICU)感染病原菌分布情况及耐药性。方法:回顾性分析2019年12月—2022年12月阜宁县人民医院收治的120例ICU患者的病例资料。统计ICU患者院内感染发生情况及病原菌分布特征,分析ICU院内感染患者耐药情况。结果:120例ICU患者共有30例发生院内感染,院内感染的发生率为25.00%。120例ICU院内感染患者共检出菌株35株,其中20株为革兰阴性菌,占病原菌总株数的57.14%,12株为革兰阳性菌,占病原菌总株数的34.29%,3株为真菌,占病原菌总株数的8.57%。对肺炎克雷伯菌、大肠埃希菌两种主要革兰阴性菌进行耐药性分析:肺炎克雷伯菌对头孢唑啉、左旋氧氟沙星、头孢吡肟的耐药率均>50.00%;肺炎克雷伯菌对亚胺培南、红霉素的耐药率最低,均为20.00%,对头孢唑啉的耐药率最高,为100.00%。大肠埃希菌对氨苄西林、莫西沙星的耐药率均≥50.00%;大肠埃希菌对亚胺培南的耐药率最低,为0,对氨苄西林的耐药率最高,为75.00%。对金黄色葡萄球菌、表皮葡萄球菌两种主要革兰阳性菌进行耐药性分析;金黄色葡萄球菌对氨苄西林、左旋氧氟沙星、红霉素的耐药率均>50.00%;表皮葡萄球菌对氨苄西林、红霉素的耐药率均为100.00%;金黄色葡萄球菌对莫西沙星的耐药率为0;表皮葡萄球菌对利福平的耐药率为0。结论:ICU患者检出病原菌以革兰阴性菌为主,多数病原菌存在不同程度的耐药,在临床治疗中需根据药敏结果有针对性地进行合理用药。

基于联络馈线负载率松弛约束的中压配电网供电单元划分

当前中压配电网供电单元划分时未能充分考虑相互联络馈线间所供负荷的互补特性,易造成供电单元数量偏多、整体线路利用效率偏低等问题,为此提出了一种基于负载率松弛约束的供电单元划分方法。构建了以供电单元数量最少、各供电单元内N-1校验后转供馈线负载率均衡为目标的中压配电网供电单元划分数学模型;解析了网格中站内供电单元与站间供电单元之间的划分次序问题,并提出了基于馈线负载率松弛约束的站间供电单元划分方法及以此为基础的站内供电单元划分方法。通过实例分析验证所提模型和方法可以对供电单元进行合理划分,节约变电站出线条数与供电单元数量,有效提高配电线路的资产利用效率。