scholarly journals Performance Evaluation of Control Methods for PV-Integrated Shading Devices

Energies ◽  
2020 ◽  
Vol 13 (12) ◽  
pp. 3171
Author(s):  
Sung Kwon Jung ◽  
Youngchul Kim ◽  
Jin Woo Moon
Keyword(s):  
Tilt Angle ◽  
Control Method ◽  
System Modeling ◽  
The Other ◽  
Control Methods ◽  
Visual Comfort ◽  
Ann Model ◽  
Indoor Space ◽  
Shading Devices ◽  
Shading Device

This study aimed to develop a building-integrated photovoltaic (BIPV) device and optimal control methods that increase the photovoltaic (PV) efficiency and visual comfort of the indoor space. A louver-type PV-integrated shading device was suggested and an artificial neural networks (ANN) model was developed to predict PV electricity output, work plane illuminance, and daylight glare index (DGI). The slat tilt angle of the shading device was controlled to maximize PV electricity output based on three different strategies: one without visual comfort constraints, and the other two with visual comfort constraints: work plane illuminance and DGI. Optimal tilt angle was calculated using predictions of the ANN. Experiments were conducted to verify the system modeling and to evaluate the performance of the shading device. Experiment results revealed that the ANN model successfully predicted the PV output, work plane illuminance, and DGI. The PV-integrated shading device was more efficient in producing electricity than the conventional wall-mount PV systems, the control method without visual comfort constraints was most efficient in generating electricity than the other two with such constraints, and excluding the constraints resulted in less comfortable visual environment and reduced energy benefit. From the results analysis, it can be concluded that based on the accurate predictions, the PV-integrated shading device controlled using the proposed methods produced more electricity compared to the wall-mount counterpart.

Effects of Indoor Lighting on Occupants’ Visual Comfort and Eye Health in a Green Building

2010 ◽  
Vol 20 (1) ◽  
pp. 75-90 ◽  
Author(s):  
Taeyon Hwang ◽  
Jeong Tai Kim
Keyword(s):  
Psychological Health ◽  
Green Building ◽  
Personal Characteristics ◽  
Visual Display ◽  
Visual Comfort ◽  
Visual Display Terminal ◽  
Eye Health ◽  
Shading Devices ◽  
Shading Device ◽  
Indoor Lighting

This study investigated the effects of indoor lighting on occupants’ visual comfort and eye health and to contribute to the management and maintenance of buildings. The illuminance of the working plane and windows at Samsung Corporation Headquarters were measured, and 2744 healthy occupants of Samsung Corporation were surveyed regarding the indoor lighting environment via the company’s intranet for 1½ years. This building was certified with the highest ranking by Korea’s Green Building Council. The cumulative data reflected the management and maintenance of the building, such as screen-type shading devices automatically controlled by seasons and time, improvement of visual display terminal glare by the veiling reflection on monitors, efficiency of artificial lighting arrays, and so on. The data were analysed for occupants’ visual comfort and eye health. The result showed that daylighting could improve the occupants’ psychological health and productivity. The screen-type shading device could intercept direct sunlight and reduce annoyance glare. However, the indoor lighting and visual environment of the building were poor. After examining the questionnaire feedback concerning improvements, the occupants’ annoyance ratio was significantly reduced, and approximately 5% of the occupants’ annoyance ratio was deemed to be caused by personal characteristics related to the lighting of the environment.

scholarly journals THERMAL-DAYLIGHTING BALANCE THROUGH BUILDING SHADING DEVICES: A REVIEW ON FACTORS AND METHODS

2021 ◽  
Vol 8 (3) ◽  
pp. 157
Author(s):  
Aimi Zahirah Zulkarnain ◽  
Mohd Najib Mohd Salleh ◽  
Zalena Abdul Aziz
Keyword(s):  
Energy Performance ◽  
Sustainable Building ◽  
High Performing ◽  
Indoor Space ◽  
Performance Factors ◽  
Negative Effect ◽  
Shading Devices ◽  
Shading Device ◽  
Optimum Balance ◽  
Parameter Relation

Daylighting is interpreted as natural sunlight allowed into an indoor space. Passive lighting strategies are considered fundamental in achieving a high performing sustainable building, which affects the visual and thermal comfort, and energy performance of a building. Many strategies in controlling daylighting are known, however, the wrong implementation can lead to a negative effect. The results obtained need to reach a balance between daylighting and thermal performance. This review is conducted to analyse the concept and factors that affect the balance through different research parameters. The performance factors include energy, comfort and perception or view. The different methods of achieving the balance are categorized into three, which are parameter relation, combination, and multi-objective optimization. Building shading devices are considered as one of the major solutions to reach thermal-daylighting balance. Through a comprehensive review, adjustable shading control is recommended as a better option for building shading device for buildings to achieve the optimum balance.

scholarly journals Thermal and Lighting Consumption Savings in Classrooms Retrofitted with Shading Devices in a Hot Climate

Energies ◽  
2018 ◽  
Vol 11 (10) ◽  
pp. 2790 ◽  
Author(s):  
Carmen Calama-González ◽  
Rafael Suárez ◽  
Ángel León-Rodríguez
Keyword(s):  
Air Conditioning ◽  
Visual Comfort ◽  
Cooling Systems ◽  
Use Patterns ◽  
Hot Climate ◽  
Shading Devices ◽  
Ambient Systems ◽  
Shading Device ◽  
Current Energy ◽  
Operative Temperatures

Most educational buildings in southern Spain do not meet current energy requirements as weak thermal envelopes and the lack of cooling systems lead to severe discomfort in classrooms, especially when temperatures are above 30 °C. Given that global warming is expected to worsen this situation in coming decades, one of the first steps to be taken is to protect window openings from high levels of solar radiation by adding shading devices to reduce indoor temperatures and improve visual comfort. The aim of this research is to evaluate the reduction in thermal and lighting consumption in a classroom where a solar protection system in the form of an egg-crate shading device was installed. Two classrooms—one with an egg-crate device and another with no shading system—were monitored and compared for a whole year. The use of an egg-crate device in these classrooms reduced indoor operative temperatures during warmer periods while also improving indoor natural illuminance levels. Moreover, annual electric air conditioning consumption decreased by approximately 20%, with a 50% reduction in electric lighting consumption. These savings in electricity were largely conditioned by the use patterns observed in these ambient systems.

scholarly journals The Effect of Depth Shading Device on Inner Space Illumination in Jakarta

2019 ◽  
Vol 1 (1) ◽  
pp. 23-29
Author(s):  
Murwantoro Panghargiyo
Keyword(s):  
Reference Point ◽  
Strong Influence ◽  
The Other ◽  
The South ◽  
Natural Lighting ◽  
The North ◽  
Illumination Effect ◽  
North Direction ◽  
Shading Devices ◽  
Shading Device

This research tries to reveal the performance of shading devices towards quantity of natural lighting entering the room. Investigation concerning shading devices (ratio between the depth of shading devices and the height of fenestration) that suitable with illumination standard needs to be done. This research also tries to find out the influence of shading devices orientation on illuminance received by the room. This research examines the performance of three types external shading devices (eggcrate, overhang, sidefins) towards natural lighting entering the room. The analysis performed by Radiance IES software for illuminance performance entering the room. Maximum illuminance reduction for three types of shading device achieved to north direction in R1 reference point. While minimum reduction for overhang and sidefins achieved to south orientation in R2 reference point. Except for eggcrate minimum illuminance reduction achieved to west direction in R2 reference point. It can be concluded that in general the three basic models of shading device have a strong influence on the direction towards the north and have a small effect on the direction of the south. In addition to the three basic elements of the shading element, the type of eggcrate shading device has the greatest effect of reducing illumination compared to the other two types. While the sidefins type has the smallest illumination effect.

scholarly journals Comparative field tests of an electrochromic shading device - thermal and visual comfort

2021 ◽  
Vol 2069 (1) ◽  
pp. 012222
Author(s):  
A Nocente ◽  
O Oksavik ◽  
L Gullbrekken ◽  
S Grynning
Keyword(s):  
Control Strategies ◽  
Field Tests ◽  
Comparative Test ◽  
The Other ◽  
Visual Comfort ◽  
Electrochromic Devices ◽  
Smart Windows ◽  
Comparative Tests ◽  
Solar Shading ◽  
Shading Device

Abstract Electrochromic devices (EC), or Smart Windows, are amongst the most promising technologies to increase users’ wellbeing in buildings. A comparative test of EC windows performance was realised in the ZEB Test Cell Laboratory in Trondheim, Norway. Two identical rooms were used for the comparative tests. One of the rooms was equipped with EC devices. The other room was equipped with a traditional insulated glazing unit (IGU) with external solar shading device. Three automatic control strategies were tested in this experiment. The EC device demonstrated a good impact on the thermal and visual comfort when compared to a traditional IGU without moveable shading and a traditional IGU with an external screen.

Addressing Closed-Chain Dynamics for High-Precision Control of Hydraulic Cylinder Actuated Manipulators

2018 ◽  
Author(s):  
Janne Koivumäki ◽  
Wen-Hong Zhu ◽  
Jouni Mattila
Keyword(s):  
High Precision ◽  
Inverse Dynamics ◽  
Control Method ◽  
System Modeling ◽  
Hydraulic Cylinder ◽  
Control Methods ◽  
Open Chain ◽  
Precision Control ◽  
Closed Chain ◽  
Highly Nonlinear

Nonlinear model-based (NMB) control methods have been shown (both in theory and in practice) to provide the most advanced control performance for highly nonlinear hydraulic manipulators. In these methods, the inverse dynamics of a system are used to proactively generate the system actuation forces from the desired motion dynamics. To model the inverse dynamics in articulated systems, the Lagrange dynamics and the Newton-Euler dynamics are the most common methods. In hydraulic cylinder actuated manipulators, a linear motion of the cylinder can be converted to a rotational joint motion between two links, creating closed-chain structures in the system. In Lagrange-dynamics-based control methods, the closed-chain structures are typically treated as an open-chain structure, which may raise the question of inaccurate system modeling. Contrary, the virtual decomposition control (VDC) approach is the first rigorous NMB control method to take full advantage of Newton-Euler dynamics, allowing to address the system nonlinear dynamics without imposing additional approximations. In VDC, the actuated closed-chain structures can be virtually decomposed to open chain structures. To address the dynamics between the decomposed open chains, three specific terms (namely two load distribution factors and an internal force vector) need to be addressed. However, analytical solutions for these terms cannot be found in the literature. This paper provides the detailed solutions for these terms, which are further needed in a high-precision control of hydraulic robotic manipulators.

Comparison of Two Control Methods for Minimally Invasive Surgical Instruments

2012 ◽  
Vol 6 (2) ◽  
Author(s):  
Chunman Fan ◽  
Hélène Clogenson ◽  
Paul Breedveld ◽  
John J. van den Dobbelsteen ◽  
Jenny Dankelman
Keyword(s):  
Control Method ◽  
Random Order ◽  
Work Load ◽  
Surgical Instruments ◽  
The Other ◽  
Control Methods ◽  
Performance Time ◽  
Minimally Invasive Surgical ◽  
Significant Difference ◽  
Measurement Session

Laparoscopic surgery is performed with long and slender instruments through one or several incisions in the abdominal wall. Steerable instruments with flexible distal tips have been developed for improving the ease of access to anatomic structures. However, the development of an intuitive and efficient control method for such steerable instruments remains a challenge. To determine which interface are most intuitive and effective to control steerable instruments, the current study evaluates the performance of novices in orienting the tip of a steerable laparoscopic forceps using thumb control or wrist control. Using two steerable instruments, one controlled by the thumb and the other by the wrist, 24 novices were divided into two groups that had to carry out an experimental task in an EndoTrainer with one of the two instruments. The participants had to orient the tip of the instrument relative to five targets that were presented in a random order. After a break, the participants switched to a second measurement session with the other instrument, followed by a third measurement session with the first instrument. Each participant performed the task 240 times over the three measurement sessions. The performance was assessed by measuring the performance time, using a questionnaire and grading the work load. The performance time showed a significant learning curve for each control method. The shortest performance time was recorded during the third session with both control methods (42.7 s for thumb control and 44.6 s for wrist control). A significant difference in the performance time was observed in the second session (p <0.02) but not in the first and third session. The questionnaire showed that most participants had a preference for thumb control. After a brief training period, thumb control and wrist control did not reveal significant differences in task performance. However, thumb control was strongly preferred by the participants due to the perceptive feeling in performance.

scholarly journals Efficient Shading Device as an Important Part of Daylightophil Architecture; a Designerly Framework of High-Performance Architecture for an Office Building in Tehran

Energies ◽  
2021 ◽  
Vol 14 (24) ◽  
pp. 8272
Author(s):  
Hassan Bazazzadeh ◽  
Barbara Świt-Jankowska ◽  
Nasim Fazeli ◽  
Adam Nadolny ◽  
Behnaz Safar ali najar ◽  
...  
Keyword(s):  
High Performance ◽  
Energy Performance ◽  
Climatic Conditions ◽  
Office Buildings ◽  
Building Performance ◽  
Visual Comfort ◽  
Different Seasons ◽  
Good Potential ◽  
Shading Devices ◽  
Shading Device

(1) Background: considering multiple, and somehow conflicting, design objectives can potentially make achieving a high-performance design a complex task to perform. For instance, shading devices can dramatically affect the building performance in various ways, such as energy consumption and daylight. This paper introduces a novel procedure for designing shading devices as an integral part of daylightophil architecture for office buildings by considering daylight and energy performance as objectives to be optimal. (2) Methods: to address the topic, a three-step research method was used. Firstly, three different window shades (fixed and dynamic) were modeled, one of which was inspired by traditional Iranian structures, as the main options for evaluation. Secondly, each option was evaluated for energy performance and daylight-related variables in critical days throughout the year in terms of climatic conditions and daylight situations (equinoxes and solstices including 20 March, 21 June, 22 September, and 21 December). Finally, to achieve a reliable result, apart from the results of the comparison of three options, all possible options for fixed and dynamic shades were analyzed through a multi-objective optimization to compare fixed and dynamic options and to find the optimal condition for dynamic options at different times of the day. (3) Results: through different stages of analysis, the findings suggest that, firstly, dynamic shading devices are more efficient than fixed shading devices in terms of energy efficiency, occupants’ visual comfort, and efficient use of daylight (roughly 10%). Moreover, through analyzing dynamic shading devices in different seasons and different times of the year, the optimal form of this shading device was determined. The results indicate that considering proper shading devices can have a significant improvement on achieving high-performance architecture in office buildings. This implies good potential for daylightophil architecture, but would require further studies to be confirmed as a principle for designing office buildings.

A COMPARISON OF FOUR DAYLIGHTING METRICS IN ASSESSING THE DAYLIGHTING PERFORMANCE OF THREE SHADING SYSTEMS

2017 ◽  
Vol 12 (3) ◽  
pp. 39-53 ◽  
Author(s):  
Mohamed Boubekri ◽  
Jaewook Lee
Keyword(s):  
The Other ◽  
Design Solution ◽  
Complex Task ◽  
Quantitative Metrics ◽  
Daylighting Simulation ◽  
The Mean ◽  
Shading Devices ◽  
Shading Device ◽  
Goals And Objectives ◽  
Performance Behavior

The assessment of the daylighting performance of a design solution is a complex task due to the changing nature of daylight. A few quantitative metrics are available to designers to assess such a performance, among them are the mean hourly illuminance (MHI), the daylight factor (DF), the daylight autonomy (DA) and the useful daylight illuminance (UDI). Each of these metrics has a purpose, a set of criteria and limitations that affect the outcome of the evaluation. When to use one metric instead of another depends largely on the design goals to be achieved. Using Design Iterate Validate Adapt (DIVA) daylighting simulation program, we set out to examine the performance behavior of these four metrics with the changing dimensions of three shading devices: a horizontal overhang, a horizontal louver system, and a vertical fin system, and compare their performance behavior as the orientation changes of the window to which these devices are attached. The context is a typical classroom of a prototypical elementary school. Our results indicate that not all four metrics behave similarly as we vary the size of each shading device and as orientation changes. The lesson learned is that not all daylighting metrics lead to the same conclusions and that it is important to use the metric that corresponds to the specific goals and objectives of the design and of the daylighting solution. The UDI is the metric that leads to outcomes most different than the other three metrics investigated in this paper.

scholarly journals The Boundary Proportion Differential Control Method of Micro-Deformable Manipulator with Compensator Based on Partial Differential Equation Dynamic Model

Micromachines ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 799
Author(s):  
Xiangli Pei ◽  
Ying Tian ◽  
Minglu Zhang ◽  
Ruizhuo Shi
Keyword(s):  
Differential Equation ◽  
Partial Differential Equation ◽  
Dynamic Model ◽  
Control Method ◽  
System Modeling ◽  
Working Environment ◽  
Partial Differential ◽  
External Interference ◽  
Differential Control ◽  
Differential Control Method

It is challenging to accurately judge the actual end position of the manipulator—regarded as a rigid body—due to the influence of micro-deformation. Its precise and efficient control is a crucial problem. To solve the problem, the Hamilton principle was used to establish the partial differential equation (PDE) dynamic model of the manipulator system based on the infinite dimension of the working environment interference and the manipulator space. Hence, it resolves the common overflow instability problem in the micro-deformable manipulator system modeling. Furthermore, an infinite-dimensional radial basis function neural network compensator suitable for the dynamic model was proposed to compensate for boundary and uncertain external interference. Based on this compensation method, a distributed boundary proportional differential control method was designed to improve control accuracy and speed. The effectiveness of the proposed model and method was verified by theoretical analysis, numerical simulation, and experimental verification. The results show that the proposed method can effectively improve the response speed while ensuring accuracy.

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