scholarly journals A natural ventilation "calculator": The challenge of defining a representative 'performance sketch' in practice and research

2021 ◽  
Author(s):  
Michael Donn ◽  
Nilesh Bakshi
Keyword(s):  
High Performance ◽  
Natural Ventilation ◽  
Sound Design ◽  
Wind Speeds ◽  
Building Shape ◽  
Net Zero ◽  
Complementary Role ◽  
Window Opening ◽  
Ventilation Rates

Too often in architecture and engineering, the simplicity in early design of the apparent guarantees of HVAC equipment manufacturers wins out over the complexity of estimating the effectiveness of natural ventilation even in Net Zero Buildings. The reality is many people in offices and schools find themselves sitting at a fixed desk, in full direct sun, with the cold draft from the HVAC equipment guaranteeing that on average they are comfortable. The drawing of blinds 'solves' the immediate sun problem, but not the quality of the air. Experience with 200+ students designing low energy, high performance naturally ventilated spaces each year over the past decade has demonstrated that the formulae that exist in the literature for early estimation of window opening size have potential if presented in an appropriate format to facilitate sound design decisions. This paper reports the evolution of that format to a calculation dashboard that facilitates accounting for: outdoor and indoor CO2 levels; wind speeds and frequencies of occurrence; coincidence of periods of calm with high outdoor temperatures; window effectiveness coefficients; single-sided vs cross-ventilation options; building shape and orientation; code minimum ventilation rates; and even infiltration. The paper focuses on the limitations of the approach and its potential complementary role in the future as a Quality Assurance tool for critiquing the output of CFD studies of natural ventilation.

scholarly journals A natural ventilation "calculator": The challenge of defining a representative 'performance sketch' in practice and research

2021 ◽  
Author(s):  
Michael Donn ◽  
Nilesh Bakshi
Keyword(s):  
High Performance ◽  
Natural Ventilation ◽  
Sound Design ◽  
Wind Speeds ◽  
Building Shape ◽  
Net Zero ◽  
Complementary Role ◽  
Window Opening ◽  
Ventilation Rates

Too often in architecture and engineering, the simplicity in early design of the apparent guarantees of HVAC equipment manufacturers wins out over the complexity of estimating the effectiveness of natural ventilation even in Net Zero Buildings. The reality is many people in offices and schools find themselves sitting at a fixed desk, in full direct sun, with the cold draft from the HVAC equipment guaranteeing that on average they are comfortable. The drawing of blinds 'solves' the immediate sun problem, but not the quality of the air. Experience with 200+ students designing low energy, high performance naturally ventilated spaces each year over the past decade has demonstrated that the formulae that exist in the literature for early estimation of window opening size have potential if presented in an appropriate format to facilitate sound design decisions. This paper reports the evolution of that format to a calculation dashboard that facilitates accounting for: outdoor and indoor CO2 levels; wind speeds and frequencies of occurrence; coincidence of periods of calm with high outdoor temperatures; window effectiveness coefficients; single-sided vs cross-ventilation options; building shape and orientation; code minimum ventilation rates; and even infiltration. The paper focuses on the limitations of the approach and its potential complementary role in the future as a Quality Assurance tool for critiquing the output of CFD studies of natural ventilation.

scholarly journals Numerical Study on Natural Ventilation Characteristics of a Partial-Cylinder Opening for One-Sided-Windcatcher of Variable Air-Feeding Orientations in Taif, Saudi Arabia

2021 ◽  
Vol 13 (20) ◽  
pp. 11310
Author(s):  
Ashraf Balabel ◽  
Mamdooh Alwetaishi ◽  
Wageeh A. El-Askary ◽  
Hamza Fawzy
Keyword(s):  
Saudi Arabia ◽  
Natural Ventilation ◽  
Numerical Study ◽  
Pressure Coefficient ◽  
Opening Angle ◽  
Arid Zones ◽  
Wind Speeds ◽  
Flow Features ◽  
Ventilation Rates ◽  
Inlet Opening

To provide a clean and cheap source of natural ventilation in windy and arid zones, a windcatcher facility is the best option. This paper aims to study the effect of the inlet opening angle of a new windcatcher model with different values ranging from 60° to 90° for three different feeding orientations at leading-down, central-up, and trailing-down locations. The ventilation performance of the new one-sided windcatcher is numerically examined using CFD simulations, where the 3D RANS and k-epsilon equations are applied at different wind speeds. The flow features of the new models are analyzed and compared with a basic traditional model based on the induced air distribution, aerodynamic losses, and ventilation rates. Results revealed that the sharp edge of the inlet opening leads to an increase in the flow separation and recirculation zone, especially when the opening angle is increased. The highest pressure coefficient is achieved by the trailing-down model compared with the other windcatcher models at an opening angle of 90°. The total pressure drop and ventilation rates increase in all the new windcatcher models due to the increase in the opening angle from 60° to 90°. At identical conditions, with an opening angle of 90° and wind speed of 5 m/s, the trailing-down model achieved a higher pressure coefficient than the leading-down and central-up models by 20.55% and 37.37%, respectively. Furthermore, the trailing-down model could provide higher ventilation rates than the central-up and leading-down models by 31% and 42%, respectively. Finally, the trailing-down windcatcher model can be recommended as the best choice to provide natural ventilation at Taif City in Saudi Arabia.

The Rotterdam Initiative in Reducing Waste Discharges at Source

1991 ◽  
Vol 24 (10) ◽  
pp. 171-177
Author(s):  
T. Vellinga ◽  
J. P. J. Nijssen
Keyword(s):  
Public Relations ◽  
Action Plan ◽  
Detailed Balance ◽  
River Rhine ◽  
The North ◽  
Complementary Role ◽  
Action Programme ◽  
The North Sea ◽  
Set Up

Much of the material dredged from the port of Rotterdam is contaminated to such a degree that it must be placed in specially constructed sites. The aim of Rotterdam is to ensure that the dredged material will once again be clean. This will entail the thorough cleansing of the sources of the contamination of the sediment in the harbours and in the River Rhine. The Rotterdam Rhine Research Project (RRP) is one of the means to achieve this based on: technical research, legal research, public relations and dialogues with dischargers. The programme for five selected heavy metals is almost complete. For many heavy metal discharge points between Rotterdam and Rheinfelden, a specially devised independent load assessment has been carried out four times. Balance studies were used to determine the relative contributions of the point discharges to the total. Currently the results are being used in an attempt to negotiate agreements with a selected number of the major dischargers. At present, more detailed balance studies are being set up and exploratory measurements carried out for organic micropollutants. It may be concluded that the research is progressing successfully and methods and techniques developed seem satisfactory and broadly applicable. The Rhine Action Programme encompasses an international effort to improve the quality of the Rhine water. Although the RRP plays a modest complementary role to the Rhine Action Plan, there is no doubt of the value of this Rotterdam initiative. The mode of work followed in the RRP contains elements that can be of use in combatting the contamination of the North Sea by rivers other than the Rhine.

THE EFFECT OF PROCESSING METHODS ON THE NUTRITIONAL QUALITY OF AFRICAN BREADFRUITS (TRECULIA AFRICANA) SEEDS

2020 ◽  
Vol 16 (2) ◽  
pp. 60
Author(s):  
Nwozo Sarah Onyenibe ◽  
Julius Oluwaseun Oluwafunmilola ◽  
Stanley Udogadi Nwawuba
Keyword(s):  
Amino Acid ◽  
Amino Acid Composition ◽  
Acid Composition ◽  
Nutritional Quality ◽  
High Performance ◽  
Phytochemical Analysis ◽  
Mineral Contents ◽  
Processing Methods ◽  
African Breadfruit

The extracted seeds of African breadfruit are identified to be extremely healthy whenever it is correctly processed. Therefore, the aim of the present study was to evaluate the effects of processing methods on the nutritional quality of African breadfruit seed. A qualitative phytochemical analysis including: Alkaloid, Flavonoid, Saponin, Tannin, Anthraquinone, Terpenoids, Steroid, and Cardiac Glycosides for the different fraction of African breadfruit seed was performed using a standard method. The result revealed the presence and greater amount of phytochemical for the raw fraction; seven in eight, six in eight for steamed fraction, and four in eight for boiled and roasted respectively. Anti-nutrient, Proximate, and Mineral Content were also conducted using standard methods. The amino acid composition was determined using High-Performance Liquid Chromatography (HPLC). The results of the present study revealed that anti-nutrients including Phytate, Tannins, and Oxalate were significantly p<0.05 reduced in the boiled fraction 5.47±0.15, 3.42±0.02 and 6.89±0.05, and highest in the raw fraction 7.77±0.01, 5.09±0.03 and 9.34±0.14. The proximate composition including; percentage crude fat, Ash, Carbohydrate, Fatty acid, and Energy value were significantly lower p<0.05 in the boiled fraction relative to the other fractions. Mineral contents; calcium, magnesium, sodium, potassium, and phosphorus were also significantly p<0.05 elevated in the boiled fraction relative to the raw, steamed, and roasted fraction. The amino acid composition was highest in the roasted and boiled fraction 57.350 and 56.978, and lowest in the steamed and raw fraction 35.754 and 28.748 respectively. Therefore, boiling (cooking) is encouraged for the preparation of African breadfruit seed.

scholarly journals Development and application of a spectrophotometric method in quality evaluation of benzimidazole anthelminthics in Nairobi city county

2020 ◽  
Vol 6 (1) ◽  
Author(s):  
Johnson K. Murage ◽  
Beatrice K. Amugune ◽  
Peter Njogu ◽  
Stanley Ndwigah
Keyword(s):  
Spectrophotometric Method ◽  
High Performance ◽  
Neglected Tropical Diseases ◽  
Developing Economies ◽  
Raw Materials ◽  
Poor Quality ◽  
Prolonged Treatment ◽  
Good Precision ◽  
Market Surveillance

Abstract Background Neglected tropical diseases (NTDs) are a group of communicable diseases which are prevalent in the tropics affecting more than one billion people. Treatment and prevention of these infections is very costly to developing economies. Helminthiases are classified among NTDs. The communities afflicted are poor and have limited access to essential resources for their livelihood. Poor-quality drugs for NTDs may lead to death or prolonged treatment without achieving the desired results. The limited resources used in purchasing poor-quality drugs will therefore be wasted instead of being put to good use. Most of the methods available for the analysis of benzimidazole anthelminthics utilize high-performance liquid chromatography. They are therefore time consuming, require sophisticated and expensive equipment, utilize rare and expensive reagents and solvents, and call for skilled personnel. A simple, rapid, and inexpensive ultraviolet spectrophotometric method of analysis would therefore come in handy especially in the analysis of many samples as occurs during post-authorization market surveillance for quality. Results The suitable solvent for the spectroscopic analysis was established as 0.1 M methanolic HCl. The wavelength of analysis was set at 294 nm. Upon validation, the method was found to have good linearity. The range over which linearity was established was way beyond the 80 to 120% of the working concentration specified by the ICH. The method exhibited good precision. Out of 32 commercial samples analyzed, five (15.6%) did not comply with compendial specifications. Intra-brand batch variation was also observed. Out of three batches of product A002T analyzed, one did not comply with compendial specifications. Conclusion A major limitation in the analysis of benzimidazole anthelminthics is the lack of reliable, simple, rapid, and low-cost methods of analysis with high throughput. The developed method serves to fill this gap. It can be used in the analysis of raw materials and finished products. It can also be used in the establishment of the quality of products prior to registration. The method will prove very useful in post-market surveillance of quality of benzimidazole anthelminthics.

Robust Environmental Sensing Using UAVs

2021 ◽  
Vol 2 (4) ◽  
pp. 1-20
Author(s):  
Ahmed Boubrima ◽  
Edward W. Knightly
Keyword(s):  
Air Pollution ◽  
Gas Sensors ◽  
High Performance ◽  
Weather Conditions ◽  
Ambient Air ◽  
Mission Planning ◽  
Pollution Monitoring ◽  
Compound Pollution ◽  
Planning Algorithm

In this article, we first investigate the quality of aerial air pollution measurements and characterize the main error sources of drone-mounted gas sensors. To that end, we build ASTRO+, an aerial-ground pollution monitoring platform, and use it to collect a comprehensive dataset of both aerial and reference air pollution measurements. We show that the dynamic airflow caused by drones affects temperature and humidity levels of the ambient air, which then affect the measurement quality of gas sensors. Then, in the second part of this article, we leverage the effects of weather conditions on pollution measurements’ quality in order to design an unmanned aerial vehicle mission planning algorithm that adapts the trajectory of the drones while taking into account the quality of aerial measurements. We evaluate our mission planning approach based on a Volatile Organic Compound pollution dataset and show a high-performance improvement that is maintained even when pollution dynamics are high.

scholarly journals Proposing Alternative Solutions to Enhance Natural Ventilation Rates in Residential Buildings in the Cfa Climate Zone of Rasht

2021 ◽  
Vol 13 (2) ◽  
pp. 679
Author(s):  
Roya Aeinehvand ◽  
Amiraslan Darvish ◽  
Abdollah Baghaei Daemei ◽  
Shima Barati ◽  
Asma Jamali ◽  
...  
Keyword(s):  
Natural Ventilation ◽  
Residential Buildings ◽  
Residential Building ◽  
Ventilation Rate ◽  
Humid Climate ◽  
The Sustainable Development ◽  
Passive Strategies ◽  
Development Goals ◽  
Ventilation Rates ◽  
Ventilation Systems

Today, renewable resources and the crucial role of passive strategies in energy efficiency in the building sector toward the sustainable development goals are more indispensable than ever. Natural ventilation has traditionally been considered as one of the most fundamental techniques to decrease energy usage by building dwellers and designers. The main purpose of the present study is to enhance the natural ventilation rates in an existing six-story residential building situated in the humid climate of Rasht during the summertime. On this basis, two types of ventilation systems, the Double-Skin Facade Twin Face System (DSF-TFS) and Single-Sided Wind Tower (SSWT), were simulated through DesignBuilder version 4.5. Then, two types of additional ventilation systems were proposed in order to accelerate the airflow, including four-sided as well as multi-opening wind towers. The wind foldable directions were at about 45 degrees (northwest to southeast). The simulation results show that SSWT could have a better performance than the aforementioned systems by about 38%. Therefore, the multi-opening system was able to enhance the ventilation rate by approximately 10% during the summertime.

Pursuit of Operational Excellence

2016 ◽  
Vol 3 (2) ◽  
pp. 21-34
Author(s):  
Christine Welch ◽  
Tammi Sinha ◽  
Nigel Ward
Keyword(s):  
Change Management ◽  
Continuous Improvement ◽  
High Performance ◽  
Effective Leadership ◽  
Value Systems ◽  
Goods And Services ◽  
Team Working ◽  
Performance Teams ◽  
Operational Excellence

Operational Excellence (OE) is achieved when high performance teams are seeking for continuous improvement in well-designed processes, using appropriate tools and technologies. Excellence is underpinned by a philosophy in which problem-solving, team-working and effective leadership combine to focus upon customer needs, and all employees are empowered to act to maintain optimal flows of value. OE is clearly a desirable quality of organizations seeking both effectiveness and efficiency in their production of goods and services for customers. OE is underpinned by concepts such as team-working, effective leadership and change management, and depends upon effective flows of value. Systems Thinking (ST) is consequently at the heart of genuine excellence. This paper was conceived in the context of a Community of Practice of business improvement professionals, who took Operational Excellence as their agenda for inquiry during sessions in 2015. Reflection upon practice discussed at these meetings, together with the literature of change management and continuous improvement, have led to development of a systemic ‘landscape' model for pursuit of Operational Excellence. The elements of this model are set out, showing how they can contribute to OE.

A simple method for evaluating image quality of screen-film system using a high-performance digital camera

2009 ◽  
Author(s):  
Naotoshi Fujita ◽  
Asumi Yamazaki ◽  
Katsuhiro Ichikawa ◽  
Yoshie Kodera
Keyword(s):  
Image Quality ◽  
High Performance ◽  
Digital Camera ◽  
Film System ◽  
Simple Method

scholarly journals Review: Sensors for Biosignal/Health Monitoring in Electronic Skin

Polymers ◽  
2021 ◽  
Vol 13 (15) ◽  
pp. 2478
Author(s):  
Hyeon Seok Oh ◽  
Chung Hyeon Lee ◽  
Na Kyoung Kim ◽  
Taechang An ◽  
Geon Hwee Kim
Keyword(s):  
High Performance ◽  
Active Component ◽  
Tactile Sensor ◽  
Wearable Devices ◽  
Advanced Technology ◽  
Electronic Skin ◽  
Points Of View ◽  
External Stimuli ◽  
Flexible Component

Skin is the largest sensory organ and receives information from external stimuli. Human body signals have been monitored using wearable devices, which are gradually being replaced by electronic skin (E-skin). We assessed the basic technologies from two points of view: sensing mechanism and material. Firstly, E-skins were fabricated using a tactile sensor. Secondly, E-skin sensors were composed of an active component performing actual functions and a flexible component that served as a substrate. Based on the above fabrication processes, the technologies that need more development were introduced. All of these techniques, which achieve high performance in different ways, are covered briefly in this paper. We expect that patients’ quality of life can be improved by the application of E-skin devices, which represent an applied advanced technology for real-time bio- and health signal monitoring. The advanced E-skins are convenient and suitable to be applied in the fields of medicine, military and environmental monitoring.

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