The economic impact of energy saving retrofits of residential and public buildings in Croatia

The purpose of this paper is to estimunate the impact of energy saving investment in residential and public buildings in Croatia for the period 2015–2020. The aim is to assess the overall socio-economic impact of energy saving renovation measures defined in Croatian strategic documents in terms of the direct, indirect and induced growth of gross value added, employment and government revenues. An estimate of the avoided costs of air pollution is also included. The overall economic impact assessment is based on an input-output methodology. From the point of view of individual investors, the benefits in terms of reduced future expenses related to energy products are usually below energy efficient renovation investment costs, making an investment financially viable only if government support is provided. If the benefits for society as a whole are included, energy efficient renovation could be assessed as viable even in the short-run. Energy saving retrofits of residential and public buildings positively contribute to economic growth, employment and protection of the environment. Because of economic growth, the tax revenues induced by these investments could compensate for government expenditures, and the overall impact on the public deficit is expected to be neutral even in the short-run.     

Nonoverlapped view management for augmented reality by tabletop projection

Augmented reality (AR) by a projector allows for the easy association of information by labeling the objects. When a projector is installed above a workspace and pointed downward, supportive information can be presented; however, the label will be deformed if the object is nonplanar. Also, a label might be projected in a region where it is hidden by the object, i.e., a blind area. In this paper, we propose a view management technique to allow interpretation by improving the legibility of the information. We propose the nonoverlapped gradient descent (NGD) method, which determines the position of a newly added label by avoiding overlap with the surrounding labels and linkage lines. The issues of presenting in a shadow or blind area are also addressed by estimating these areas based on the approximation of objects as a simple solid. The results of an experiment show that the visibility of the labels was improved by using this method.     

Tracking analysis of augmented complex least mean square algorithm

The augmented complex least mean‐square (ACLMS) algorithm is a suitable algorithm for the processing of both second‐order circular (proper) and noncircular (improper) signals. In this paper, we provide tracking analysis of the ACLMS algorithm in the non‐stationary environments. Using the established energy conservation argument, we derive a variance relation that contains moments that represent the effects of non‐stationary environment. We evaluate these moments and derive closed‐form expressions for the excess mean‐square error (EMSE) and mean‐square error (MSE). The derived expressions, supported by simulations, reveal that unlike the stationary case, the steady‐state EMSE, and MSE curves are not monotonically increasing functions of the step‐size parameter. We also use this observation to optimize the step‐size learning parameter. Simulation results illustrate the theoretical findings and match well with theory. Copyright © 2015 John Wiley & Sons, Ltd.     

An X‐FEM‐based numerical–asymptotic expansion for simulating a Stokes flow near a sharp corner

A numerical technique that is based on the integration of the asymptotic solution in the numerical framework for computing the local singular behavior of Stokes flow near a sharp corner is presented. Moffat's asymptotic solution is used, and special enriched shape functions are developed and integrated in the extended finite element method (X‐FEM) framework to solve the Navier–Stokes equations. The no‐slip boundary condition on the walls of the corner is enforced via the use of Lagrange multipliers. Flows around corners with different angles are simulated, and the results are compared with both those of the known analytic solution and the X‐FEM with no special enrichment near the corner. The results of the present technique are shown to greatly reduce the error made in computing the pressure and velocity fields near a corner tip without the need for mesh refinement near the corner. The method is then applied to the estimation of the permeability of a network of fibers, where it is shown that the local small‐scale pressure singularities have a large impact on the large‐scale network permeability. Copyright © 2014 John Wiley & Sons, Ltd.     

利用输入输出测量值设计控制系统的新方法

针对自适应控制的实际应用情况,在已有自适应模型的基础上,通过严密的数学推导,从工程应用的角度提出一种设计MRAC系统的简单而又实用的新算法,从而不必引入增广误差信号而得到自适应控制律,便于工程实现。仿真在一定程度上证明了方法的有效性。     

网络控制系统的随机最优控制综述

网络控制系统由于网络的引入而出现了数据延迟。在处理随机发生的延迟上,用最优控制的方法是比较有效的。目前为止出现了不少有关网络控制系统的最优控制的结果,论文旨在对网络控制系统的最优控制方面的研究现状进行介绍,并指出进一步研究的方向。     

基于非凸低秩约束的图像修复方法

受传输干扰或存储不当等因素的影响,现实应用中获取的某些图像通常会存在像素缺失现象,这给图像的后续分析与处理带来了一定影响.解决该问题的常用方法是对图像进行低秩修复.利用低秩特性进行修复的方法大多以秩函数建模,由于矩阵秩函数是非凸离散的,该模型的求解是一个NP难问题,所以通常利用核范数对矩阵的秩进行凸松弛.但是,基于核范...     

A new method on hydrothermal scheduling optimization in electric power market

The hydrothermal scheduling in the electric power market becomes difficult because of introducing competition and considering sorts of constraints. An augmented Lagrangian approach is adopted to solve the problem,which adds to the standard Lagrangian function a quadratic penalty term without changing its dual property,and reduces the oscillation in iterations. According to the theory of large system coordination and decomposition,the problem is divided into hydro sub-problem and thermal sub-problem,which are coordinated by updating the Lagrangian multipliers,then the optimal solution is obtained. Our results for a test system show that the augmented Lagrangian approach can make the problem converge into the optimal solution quickly.     

基于三维立体标志物的增强现实实时渲染

提出了一种基于三维立体标志物的增强现实实时渲染系统.该系统利用物体的反光特性估算现实场景中的光源位置,通过阴影算法为增强现实系统生成可信度高的实时阴影.为了得到准确的实时光照信息,此系统在原有ARToolkit标志物的基础上将2D标志物改为3D标志物,免去了以往算法前期的大量计算,根据物体上获得的光照信息生成实时的阴影.结果表明,此系统可快速地检测到室内光源的位置和数量,生成的实时阴影真实度高,使增强现实环境中的虚拟物体和真实物体能产生近乎一致的光照阴影效果.     

Optimal operation of integrated energy system including power thermal and gas subsystems

As a form of hybrid multi-energy systems, the integrated energy system contains different forms of energy such as power, thermal, and gas which meet the load of various energy forms. Focusing mainly on model building and optimal operation of the integrated energy system, in this paper, the dist-flow method is applied to quickly calculate the power flow and the gas system model is built by the analogy of the power system model. In addition, the piecewise linearization method is applied to solve the quadratic Weymouth gas flow equation, and the alternating direction method of multipliers (ADMM) method is applied to narrow the optimal results of each subsystem at the coupling point. The entire system reaches its optimal operation through multiple iterations. The power-thermal-gas integrated energy system used in the case study includes an IEEE-33 bus power system, a Belgian 20 node natural gas system, and a six node thermal system. Simulation-based calculations and comparison of the results under different scenarios prove that the power-thermal-gas integrated energy system enhances the flexibility and stability of the system as well as reducing system operating costs to some extent.