scholarly journals Microwave Attenuation and Prediction of Rain Outage for Wireless Networks in Pakistan's Tropical Region

2011 ◽  
Vol 2011 ◽  
pp. 1-6 ◽  
Author(s):  
Uzma Siddique ◽  
Laeeq Ahmad ◽  
Gulistan Raja
Keyword(s):  
Wireless Networks ◽  
Research Work ◽  
Rainfall Rate ◽  
Tropical Region ◽  
Radio Link ◽  
Tropical Regions ◽  
Microwave Attenuation ◽  
Link Performance ◽  
Communication Links ◽  
Set Up

The microwave attenuation due to rainfall in tropical regions has not been very widely studied yet. In Pakistan's tropical environment, line-of-sight microwave communication links were set up and have been operated for several years to study the microwave attenuation characteristics due to tropical rainfall. In this paper the experimental results are presented, including the cumulative distributions of microwave attenuation and the relationship between specific attenuation and rainfall rate. In addition, a rain outage prediction model is proposed which not only predicts microwave radio link performance but will also be useful in calculating the link degradations due to interference issues. The main focus of this research work has been done keeping in mind the wireless networks of Pakistan. The results show that the rainfall rate, the microwave propagation characteristics, and outage predictions in Pakistan differ from the International Radio Consultative Committee predictions and ITU recommendation P530.7/8, respectively.

scholarly journals Cumulative distributions of rainfall rate and microwave attenuation in Singapore's tropical region

Radio Science ◽  
2000 ◽  
Vol 35 (3) ◽  
pp. 751-756 ◽  
Author(s):  
Z. X. Zhou ◽  
L. W. Li ◽  
T. S. Yeo ◽  
M. S. Leong
Keyword(s):  
Rainfall Rate ◽  
Tropical Region ◽  
Microwave Attenuation

ESTIMATION OF RAIN FADE DURATIONS ON COMMUNICATION LINKS AT Ka BAND IN EQUATORIAL AND TROPICAL REGIONS

2020 ◽  
Vol 79 (2) ◽  
pp. 129-141
Author(s):  
M. E. Sanyaolu ◽  
Oluropo F. Dairo ◽  
A. A. Willoughby ◽  
L. B. Kolawole
Keyword(s):  
Ka Band ◽  
Tropical Regions ◽  
Communication Links

scholarly journals Breeding Temperate Japonica Rice Varieties Adaptable to Tropical Regions: Progress and Prospects

Agronomy ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 2253
Author(s):  
Myrish Pacleb ◽  
O-Young Jeong ◽  
Jeom-Sig Lee ◽  
Thelma Padolina ◽  
Rustum Braceros ◽  
...  
Keyword(s):  
The Philippines ◽  
Tropical Region ◽  
Japonica Rice ◽  
Rice Varieties ◽  
Temperate Japonica ◽  
Tropical Regions ◽  
Tropical Environments ◽  
Increasing Demand ◽  
Northeast Asian ◽  
The Tropics

Temperate japonica rice is mainly cultivated in temperate regions. Many temperate japonica varieties have a superior grain quality that is preferred in Northeast Asian countries such as Japan, Korea, and China. The changes in consumers’ preferences in Southeast Asia and Western countries has contributed to increasing the demand for temperate japonica. Most temperate japonica varieties developed in temperate regions typically exhibit extra-early flowering under the short-day conditions in the tropics, which usually results in severely reduced yields. Since 1992, we have been developing temperate japonica varieties that can adapt to tropical environments to meet the increasing demand for temperate japonica rice, having released six varieties in the Philippines. Especially, the yield of one of the temperate japonica varieties, Japonica 7, was comparable to the yields of leading indica varieties in the Philippines. Here, we discuss the current breeding initiatives and future plans for the development of tropical-region-bred temperate japonica rice.

scholarly journals Radio Link Quality Estimation in Low-Power Wireless Networks

2013 ◽  
Author(s):  
Nouha Baccour ◽  
Anis Koubâa ◽  
Claro Noda ◽  
Hossein Fotouhi ◽  
Mário Alves ◽  
...  
Keyword(s):  
Wireless Networks ◽  
Low Power ◽  
Link Quality ◽  
Radio Link ◽  
Quality Estimation ◽  
Low Power Wireless Networks ◽  
Link Quality Estimation

The equatorial wind structure in Jupiter’s stratosphere from direct wind and temperature measurements with ALMA and IRTF/TEXES

2021 ◽  
Author(s):  
Bilal Benmahi ◽  
Thibault Cavalié ◽  
Thomas K. Greathouse ◽  
Vincent Hue ◽  
Rohini Giles ◽  
...  
Keyword(s):  
Tropical Region ◽  
Temperature Structure ◽  
Horizontal Structure ◽  
Tropical Regions ◽  
Upper Troposphere ◽  
Thermal Wind ◽  
Wind Speeds ◽  
Wind Structure ◽  
First Time ◽  
Middle Stratosphere

<p>Since 30 years, an equatorial oscillation of the temperature structure with a quasi-period of 4 years has been discovered in the atmosphere of Jupiter (Orton et al. 1991, Leovy et al. 1991). This phenomenon results in a complex vertical and horizontal structure of prograde and retrograde jets. However, the wind structure of the stratosphere in the equatorial zone of Jupiter has not been measured directly. It has only been inferred in the tropical region from the thermal wind balance using temperatures measured in the jovian stratosphere and the cloud-top wind speeds measured as a initial condition (e.g. Flasar et al. 2004). But temperatures are not constrained between the upper troposphere and the middle stratosphere from observations, limiting thus the accuracy of the thermal wind balance.</p> <p>In this study, we derive self-consistently for the first time the structure of the tropical winds by utilizing wind and temperature observations all performed in the stratosphere. The wind speeds were obtained by Cavalié et al. (2021) at 1 mbar in Jupiter's stratosphere in both the equatorial and tropical regions in March 2017 with ALMA. The stratospheric thermal field was measured a few days before from the equator to the mid-latitudes with Gemini/TEXES (Giles et al. 2020). For the derivation of the wind, we use both the thermal wind equation (Pedlosky 1979) and the equatorial thermal wind equation (Marcus et al. 2019). In this paper, we will present and discuss our results.</p>

Utilizing SMS/3G Networks for Better and Reliable Communications between Yard Cranes and Server

2011 ◽  
Vol 2 (3) ◽  
pp. 16-29
Author(s):  
C. D. Cheng ◽  
C. C. Ko ◽  
W. J. Huang
Keyword(s):  
Wireless Networks ◽  
Communication Channel ◽  
Current Practice ◽  
Service Providers ◽  
Telecommunication Service ◽  
Infrastructure Development ◽  
3G Networks ◽  
Port Operation ◽  
Reliable Communications ◽  
Set Up

In a normal port operation, yard cranes are used to move containers from one location to another for import, export or relocation purposes. In order to locate the positions of containers, a database is set up in the office server to store the current locations of existing containers within the yard. Whenever the Rubber Tyred Gantry (RTG) crane operator moves a container around, the database has to be updated via a program installed in the Vehicle Mounted Terminal (VMT) fitted to the crane. This requires the establishment of a communication channel between the server and the crane VMT. The current practice is to make use of wireless networks, even though these are susceptible to attenuation and interferences in rugged surroundings as in a port. This paper describes and explores another alternative, that of using 2G/SMS for short messages and 3G networks for real-time scenarios. These methods are more reliable as major telecommunication service providers normally expend substantial resources in infrastructure development. They also provide a cheaper alternative in terms of reducing maintenance expenses.

A dynamic model for human thermal comfort for smart building applications

2019 ◽  
Vol 234 (4) ◽  
pp. 472-483
Author(s):  
Ghezlane Halhoul Merabet ◽  
Mohamed Essaaidi ◽  
Driss Benhaddou
Keyword(s):  
Thermal Comfort ◽  
Air Conditioning ◽  
Research Work ◽  
Comfort Level ◽  
Indoor Environments ◽  
Air Conditioning System ◽  
Human Thermal Comfort ◽  
Local Quality ◽  
Set Up ◽  
Air Conditioning Systems

Thermal comfort is closely related to the evaluation of heating, ventilation, and air conditioning systems. It can be seen as the result of the perception of the occupants of a given environment, and it is the product of the interaction of a number of personal and environmental factors. Otherwise, comfort issues still do not play an important role in the daily operation of commercial buildings. However, in the workplace, local quality effects, in addition to the health, the productivity that has a significant impact on the performance of the activities. In this regard, researchers have conducted, for decades, investigations related to thermal comfort and indoor environments, which includes developing models and indices through experimentations to establish standards to evaluate comfort and factors and set-up parameters for heating, ventilation, and air conditioning systems. However, to our best knowledge, most of the research work reported in the literature deals only with parameters that are not dynamically tracked. This work aims to propose a prototype for comfort measuring through a wireless sensor network and then presenting a model for thermal comfort prediction. The developed model can be used to set up a heating, ventilation, and air conditioning system to meet the expected comfort level. In particular, the obtained results show that there is a strong correlation between users’ comfort and variables such as age, gender, and body mass index as a function of height and weight.

scholarly journals The role of cover and rebar characteristics on load-slip behavior of reinforced concrete members in compression

2018 ◽  
Vol 162 ◽  
pp. 04017
Author(s):  
Tareq al-Attar ◽  
Qais Hassan ◽  
Sura Mejbel ◽  
Hussein Dawood
Keyword(s):  
Bond Strength ◽  
Research Work ◽  
Compressive Load ◽  
Concrete Block ◽  
Concrete Cover ◽  
Cross Sectional ◽  
Testing Procedures ◽  
Concrete Members ◽  
Significant Difference ◽  
Set Up

This paper describes a part of an extensive research work devoted to evaluate the bond strength between rebars and concrete through different testing procedures. Main parameters in this part are the concrete cover and rebar diameter. The tested specimen consisted of a single bar embedded in a concrete block with square cross-sectional area and is being tested under compressive load. Three concrete block sizes were cast to offer three different cover for the embedded rebars. The dimensions of these blocks were; 150×150×135, 100×100×135 and 200×200×185 mm. Three bar diameters, 12, 16 and 20 mm, were investigated. The specimens were water-cured and tested at the ages of 7 and 28 days. A new proposed test set-up was used to monitor the load-slip behavior of the specimens. The test results showed that there is no significant difference in bond energy between the two curing ages, 7 and 28 days. The concrete cover has a significant effect on the bond strength between rebar and concrete. By increasing the cover, the confinement offered by concrete increases, bond strength increases, and slip increases. Based on the present results, a concept of effective cover was developed. This concept showed a high correlation with the mode of failure for the tested specimens.

scholarly journals Semi-Transparent Building Integrated Photovoltaic Solar Glazing: Investigations of Electrical and Optical Performances for Window Applications in Tropical Region

2019 ◽  
Vol 2019 ◽  
pp. 1-10
Author(s):  
Benedicto Joseph ◽  
Baraka Kichonge ◽  
Tatiana Pogrebnaya
Keyword(s):  
Air Temperature ◽  
Light Transmission ◽  
High Heat ◽  
Tropical Region ◽  
Optical Parameters ◽  
Solar Pv ◽  
Efficacy Evaluation ◽  
Energy Efficiency Improvement ◽  
Window Applications ◽  
Set Up

Integrating solar PV technology with semi-transparent windows permits multifunctional operation as electricity generation and allowing natural light to enter the building, hence overall energy efficiency improvement. The performance of the semi-transparent building integrated PV glazing on office building facade has been investigated in Tanzania’s tropical climate. Experimental measurements of the electrical and optical parameters for the system efficacy evaluation were done at various conditions which included cloudy, normal, and clear sky days. The weather parameters under consideration were solar irradiance, air temperature, relative humidity, and wind speed. The experimental set-up consisted of building integrated silicon mono crystalline semi-transparent PV module rated at 50 W and accessories. The I-V and P-V curves were measured at different irradiances. Throughout the experiment, the observed module temperature was between 20°C and 51°C and the air temperature was 17–33°C while the humidity was recorded at the range of 23–63%. Module electrical efficiency was observed to vary from 4% to 9% while the visible light transmission was obtained between 11% and 19%. It was proved that at high temperature regardless of irradiance increase, there were observed output power and efficiency drops caused by high heat losses.

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