Integrating Smart Ceiling Fans and Communicating Thermostats to Provide Energy-Efficient Comfort

The project goal was to identify and test the integration of smart ceiling fans and communicating thermostats. These highly efficient ceiling fans use as much power as an LED light bulb and have onboard temperature and occupancy sensors for automatic operationbased on space conditions. The Center for the Environment (CBE) at UC Berkeley led the research team including TRC, Association for Energy Affordability (AEA), and Big Ass Fans (BAF). The research team conducted laboratory tests, installed99 ceiling fans and 12 thermostats in four affordable multifamily housing sites in California’s Central Valley, interviewed stakeholders to develop a case study, developed an online design tool and design guide, outlined codes and standards outreach, and published several papers.The project team raised indoor cooling temperature setpoints and used ceiling fans as the first stage of cooling; this sequencing of ceiling fans and air conditioningreducesenergy consumption, especially during peak periods, while providing thermal comfort.The field demonstration resulted in 39% measured compressor energy savings during the April–October cooling seasoncompared to baseline conditions, normalized for floor area. Weather-normalized energy use varied from a 36% increase to 71% savings, withmedian savings of 15%.This variability reflects the diversity in buildings, mechanical systems, prior operation settings, space types, andoccupants’ schedules,preferences, and motivations. All commercial spaces with regular occupancy schedules (and twoof the irregularly-occupied commercial spaces and one of the homes) showed energy savings on an absolute basis before normalizing for warmer intervention temperatures,and 10 of 13 sites showed energy savings on a weather-normalized basis. The ceiling fans provided cooling for one site for months during hot weather when the coolingequipment failed.Occupants reported high satisfaction with the ceiling fans and improved thermal comfort. This technology can apply to new and retrofit residential and commercial buildings

Modelling the robustness properties of HVAC plant under feedback control

Most existing building simulation programs fail to capture sufficient of the underlying dynamics of nonlinear HVAC plant and some have restricted room space modelling capabilities for low-time-horizon analyses. In this work, a simplified model of a room space with hot water heating and a chilled ceiling system is developed for the main purpose of analysing control system response. The room model is based on a new approach to lumped capacitance modelling and the heating and chilled ceiling emitters are modelled using third-order descriptions. Control system components are treated in detail and both controllers are ‘tuned’ at a nominal region of plant operation using a gradient-descent-based optimization procedure. Robustness qualities of the controllers are analysed with reference to extremes in plant operating conditions. A key feature of the work is the transparency of the modelling procedure, designed to have appeal to researchers as well as practitioners involved with HVAC control system design problems

The design of reinforced concrete ceiling

Bakalářská práce je zaměřena na statické řešení monolitické spojité železobetonové stropní konstrukce a průvlaku v jednoduchém rodinném domu. Celá konstrukce stropu je navržena ze železobetonu. Pro stanovení účinků od zatížení je použit výpočetní program Dlubal RFEM, pracující s metodou konečných prvků. Posouzení prvků je provedeno podle 1. a 2. mezního stavu. Práce obsahuje vypracování statického výpočtu, dimenzování výztuže, výkresu tvaru a výkresů výztuže řešených prvků.The bachelor thesis is focused on the static solution of monolithic reinforced concrete continuous ceiling and a beam in a single family house. The entire structure of ceiling is designed of reinforced concrete. Software Dlubal RFEM is used to determine the effects of load. It works with the finite element method. Assessment of elements is according to the first limit state and also the second limit state. The thesis includes statics calculation, dimensioning of reinforcement, drawing of shape and reinforcement drawings of solved elements.

Ceilings of Palacio del Infantado, a virtual reconstruction

The Cazadores Room was a rectangular room, located on the main floor of the south wing, and which is covered with a coffered ceiling, the largest of all, shaped like an inverted coffered ceiling, polychromatic and constructed based on interlocking strips. Communication will examine and explain how, through documented sources and the remains preserved after the fire, it is possible to get a precise picture of this coffered ceiling, explaining its design and construction; analyzing its floor plan, its different components, delving in the assembly plans and construction procedures to do so.Peer Reviewe

Rat Races and Glass Ceilings- Career Paths in Organizations

In an ongoing organization, such as a large law partnership, employees are motivated not only by current rewards but also by the prospect of promotion, and the opportunity to influence policy and make rules in the future. This leads to a dynamic programming problem in contract design. We model career design in such a firm as a recursive mechanism design problem in an overlapping generations environment. Agents entering the firm may differ in their private characteristics which affect their costs of effort. We find that under recursive structure, a profit-maximizing principal offers, and promotion-motivated agents accept, "rat-race" contracts with very low wages and high effort levels. With wages driven down to zero, promotions become the main instrument to discriminate among agents in an adverse selection environment. The optimal adverse selection contract introduces a promotion barrier, or a "glass ceiling", for the high cost agents. We thus find that the issues of inefficiently high work levels (the "rat-race") and of unequal promotion rates (the "glass ceiling") are intimately interconnected. We apply this framework to equal opportunity and gender discrimination in employmentrecursive contracts, mechanism design, overlapping generations, rat-race, glass ceiling

Target Acquisition in Multiscale Electronic Worlds

Since the advent of graphical user interfaces, electronic information has grown exponentially, whereas the size of screen displays has stayed almost the same. Multiscale interfaces were designed to address this mismatch, allowing users to adjust the scale at which they interact with information objects. Although the technology has progressed quickly, the theory has lagged behind. Multiscale interfaces pose a stimulating theoretical challenge, reformulating the classic target-acquisition problem from the physical world into an infinitely rescalable electronic world. We address this challenge by extending Fitts’ original pointing paradigm: we introduce the scale variable, thus defining a multiscale pointing paradigm. This article reports on our theoretical and empirical results. We show that target-acquisition performance in a zooming interface must obey Fitts’ law, and more specifically, that target-acquisition time must be proportional to the index of difficulty. Moreover, we complement Fitts’ law by accounting for the effect of view size on pointing performance, showing that performance bandwidth is proportional to view size, up to a ceiling effect. The first empirical study shows that Fitts’ law does apply to a zoomable interface for indices of difficulty up to and beyond 30 bits, whereas classical Fitts’ law studies have been confined in the 2-10 bit range. The second study demonstrates a strong interaction between view size and task difficulty for multiscale pointing, and shows a surprisingly low ceiling. We conclude with implications of these findings for the design of multiscale user interfaces

Graph colouring for office blocks

The increasing prevalence of WLAN (wireless networks) introduces the potential of electronic information leakage from one company's territory in an office block, to others due to the long-ranged nature of such communications. BAE Systems have developed a system ('stealthy wallpaper') which can block a single frequency range from being transmitted through a treated wall or ceiling to the neighbour. The problem posed to the Study Group was to investigate the maximum number of frequencies ensure the building is secure. The Study group found that this upper bound does not exist, so they were asked to find what are "good design-rules" so that an upper limit exists

Numerical analysis of diffuse ceiling ventilation and its integration with a radiant ceiling system

A novel system combining diffuse ceiling ventilation and radiant ceiling was proposed recently, with the aim of providing energy efficient and comfort environment to office buildings. Designing of such a system is challenging because of complex interactions between the two subsystems and a large number of design parameters encountered in practice. This study aimed to develop a numerical model that can reliably predict the airflow and thermal performance of the integrated system during the design stage. The model was validated by experiments under different operating conditions. The validated model was further applied to evaluate the effects of different design parameters, including the U-value of the diffuse ceiling panel, plenum height, plenum depth, and inlet configuration. In the integrated system, diffuse ceiling separated the radiant ceiling from the rest of the room and consequently changed the energy efficiency of the radiant system. The simulated results demonstrated that using ceiling panel with a higher U-value can minimize this impact and make the system to cool down space efficiently. Low plenum height was beneficial to the energy efficiency, but aggravated the non-uniformity air distribution and further led to the draught problem in the occupied zone. This system was recommended to apply in the small offices instead of large, open spaces.<br/