Search results for " ai"
showing 10 items of 2441 documents
Energy performance improvements of a DEC system due to wet heat exchangers
2011
This work concerns an innovative desiccant and evaporative cooling (DEC) system for building air conditioning. The original system is an experimental DEC air handling unit installed at the Solar Laboratory of the University of Palermo and recently modified and updated. With the aim to increase the cooling effect due to water evaporation in the return air flow rate, the sensible heat exchanger was replaced with two cross flow flat plate heat exchangers installed in series, with continuous humidification of the secondary air flow. The new thermodynamic cycle is theoretically described and the realization of the real application is shown. Detailed operational data and energy performance indica…
Experimental results on adsorption beds for air dehumidification
2016
Desiccant rotors are commonly used in large scale solar cooling open cycle applications. As is well known, adsorption heat sensibly reduces the dehumidification capacity of the desiccant material and results in lower system performance. The aim of this work is to describe an innovative solution that permits simultaneous mass and heat transfer. In particular, two components working with silica gel fixed beds were studied and compared. The first component is a simple packed bed containing silica gel grains. The second component is a fin and tube heat exchanger commonly used in several air conditioning applications wherein the spaces between the fins are filled with silica gel grains. In this …
Life Cycle Assessment of a compact Desiccant Evaporative Cooling system: The case study of the “Freescoo”
2016
Abstract The paper aims at exploring the performances of a compact Desiccant Evaporative Cooling system called “Freescoo” (Free Solar Cooling) in comparison to standard conventional technologies. The Freescoo – that aims at applications in the residential sector and in small office buildings and includes a photovoltaic–thermal system – is analyzed, its monitored performance discussed and reported: under cooling conditions an Energy Efficiency Ratio of 12.8 is calculated, that reaches 50.7 if also photovoltaic generation is considered. To assess the performance of the proposed system a Life Cycle Assessment study was performed to investigate the system covering all its life, from the product…
ADVANCED SOLAR ASSISTED DESICCANT AND EVAPORATIVE COOLING SYSTEM EQUIPPED WITH WET HEAT EXCHANGERS
2011
Abstract This work concerns an innovative solar assisted desiccant and evaporative cooling (DEC) system for building air conditioning. In this system, air-to-air packaged wet heat exchangers are used to maximize the exploitation of the evaporative cooling potential associated with the exhaust air stream. The thermodynamic cycle is first theoretically described, and then an example of a real application is shown. The system presented is an experimental DEC system originally installed at the beginning of 2008 at the Solar Laboratory of the University of Palermo and recently modified and updated. These modifications have been implemented with the aim to foster some problems related to the conv…
Acetone measurements in the exhaled air by the cavity ring-down spectrometry
2020
Our work is focused to develop sensitive optical diagnostic methods for the detection of Volatile Organic Compounds in the breath. For the breath measurements, we have built a cavity ring-down spectrometer, operated in the UV region. The system was tested and calibrated using a KinTek automated permeation tube system with nitrogen as a carrier gas, as well as self- prepared acetone mixtures in air with known concentrations. In this paper, we present results of the measurements of acetone concentration in the breath for the test group of randomly selected 40 people in the age group over 50. We observed the values of acetone concentration in the breath in the range from 0,1 – 80 ppm, with a m…
RIGA International Airport development in Baltic Sea region aviation industry context
2021
In the paper the authors examined key Latvian economy indicators, specifically focusing on trends in development of aviation industry development. In particular, also attention was paid to passengers and cargo volume transportation dynamics, as well as to RIGA International Airport Development Plan through the year 2036. The authors compared operations of RIGA International Airport with available data from other leading Baltic Sea Region airports, specifically within 300 kilometres zone. Another requirement was, a competing airport had to be in the TOP 100 airports globally to be considered. KEY WORDS: RIGA International Airport, Baltic sea region, development plan. JEL CODES: M160, R110, R…
Mode of Delivery and the Effectiveness of Foreign Aid: The Example of Missionary Work
2010
Conventional development aid, typically a service from government to government, has been a relatively poor determinant of economic growth or human development in developing countries. In this paper we test whether a distinctly grass-roots delivery mode, as is the case with missionary work, leads to a more effective dispersion of foreign aid. In addition to its mode of delivery, missionary work is also of interest as there is a known positive correlation between the growth rate of Christianity and economic development. We estimate the economic growth impacts of development aid versus missionary work variables by using empirical data from 119 countries and discuss several explanations for ou…
A Dual-Process Model Applied to Two Health-Promoting Nutrition Behaviours
2021
We tested a dual process model incorporating constructs that reflect both performing the target behaviour (behaviour directed habit) and habits that run counter to the target behaviour (opposing behaviour habit) in accounting for variance in two health behaviours: eating the recommended serves of fruits and vegetables a day and restricting sugar-sweetened beverage consumption. A prospective correlational design with two waves of data collection separated by one week was adopted. Participants (N = 606) comprising middle school students (n = 266) and university students (n = 340) completed an initial survey comprising self-report measures of past behaviour, intention, and habit to perform the…
Dezinfekcijas līdzekļu un individuālo aizsarglīdzekļu ietekme uz māsas pašsajūtu ķirurģijas nodaļā
2022
Bakalaura darba tēmas nosaukums ir “Dezinfekcijas līdzekļu un individuālo aizsarglīdzekļu ietekme uz māsas pašsajūtu ķirurģijas nodaļā”. Ņemot vērā, ka dezinfekcijas līdzekļi tiek ražoti koncentrētāki, kā arī individuālie aizsarglīdzekļi tiek pielietoti aizvien vairāk, to pielietojums ir paredzēts, lai aizsargātu māsas un citu ārstniecības personāla un pacienta veselību, tomēr šie līdzekļi var ietekmēt māsas pašsajūtu- pasliktinot gan fizisko, gan psihoemocionālo stāvokli, tad par bakalaura darba mērķi tika izvirzīts- noskaidrot dezinfekcijas līdzekļu un individuālo aizsarglīdzekļu lietošanas ietekmi uz māsas pašsajūtu ķirurģijas nodaļā. Uzsākot pētījuma darbu, tika izvirzīts arī pētījuma j…
Linguistica Lettica, Nr. 30
2022
Žurnāla "Linguistica Lettica" 30. numura tēma ir "Valodas bagātība slēpjas tās dažādībā". The theme of the 30th issue of the annual journal "Linguistica Lettica" is "The richness of language lies in its diversity".