scholarly journals Diabatic Heating and Cooling Rates Derived from In Situ Microphysics Measurements: A Case Study of a Wintertime U.K. Cold Front

2014 ◽  
Vol 142 (9) ◽  
pp. 3100-3125 ◽  
Author(s):  
C. Dearden ◽  
P. J. Connolly ◽  
G. Lloyd ◽  
J. Crosier ◽  
K. N. Bower ◽  
...  
Keyword(s):  
Diabatic Heating ◽  
Cold Front ◽  
Phase Changes ◽  
Ice Crystals ◽  
Model Framework ◽  
Cooling Rates ◽  
Model Calculations ◽  
Heating And Cooling

In situ measurements associated with the passage of a kata cold front over the United Kingdom on 29 November 2011 are used to initialize a Lagrangian parcel model for the purpose of calculating rates of diabatic heating and cooling associated with the phase changes of water within the cloud system. The parcel model calculations are performed with both bin-resolved and bulk treatments of microphysical processes. The in situ data from this case study reveal droplet number concentrations up to 100 cm−3, with planar ice crystals detected at cloud top, as well as columnar crystals produced by rime splinter ejection within the prefrontal warm sector. The results show that in terms of magnitude, the most significant rates of diabatic heating and cooling are produced by condensation growth of liquid water within the convective updrafts at the leading edge of the front. The peak temperature tendencies associated with condensation are typically found to be at least an order of magnitude larger than those associated with the ice phase, although the cooling effect from sublimation and melting occurs over a wide region. The parcel model framework is used in conjunction with the observations to assess the suitability of existing bulk microphysical treatments, of the kind used in operational weather forecast models. It is found that the assumption of spherical ice crystals (with diameters equal to the maximum dimension of those sampled), along with the use of negative exponential functions to describe ice particle size distributions, can lead to an overestimation of local diabatic heating and cooling rates by a factor of 2 or more.

Texture Evolution Under Fast Heating and Cooling Rates of Zirconium Alloys Studied In-Situ by Synchrotron X-Ray Diffraction

2020 ◽  
Author(s):  
Chi-Toan Nguyen ◽  
Alistair Garner ◽  
Javier Romero ◽  
Antoine Ambard ◽  
Michael Preuss ◽  
...  
Keyword(s):  
Texture Evolution ◽  
Zirconium Alloys ◽  
X Ray Diffraction ◽  
Fast Heating ◽  
Cooling Rates ◽  
X Ray ◽  
Heating And Cooling

EBSD Coupled to SEM In Situ Annealing as a Tool to Identify Recrystallization Mechanisms - Application to Zr and Ta Alloys

2012 ◽  
Vol 715-716 ◽  
pp. 486-491
Author(s):  
Nathalie Bozzolo ◽  
S. Jacomet ◽  
M. Houillon ◽  
B. Gaudout ◽  
Roland E. Logé
Keyword(s):  
High Temperature ◽  
Short Duration ◽  
Microstructure Evolution ◽  
Room Temperature ◽  
Heat Treatments ◽  
Cooling Rates ◽  
Heating And Cooling ◽  
Orientation Mapping ◽  
High Heating

A heating stage as been developed to perform in-situ annealing in a SEM equipped with an EBSD system in order to study recrystallization mechanisms. High temperature treatments could then be performed inside the SEM, up to 1180°C and with high heating-and cooling-rates (~100°C.s-1). Samples were cooled down to room temperature to perform EBSD orientation mapping in between successive short-duration heat-treatments. Microstructure evolution snapshots obtained this way are presented in this paper to show recrystallization in Zircaloy4 and in pure tantalum.

scholarly journals Evidence for the role of the diabatic heating in synoptic scale processes: a case study example

1997 ◽  
Vol 15 (4) ◽  
pp. 487-493 ◽  
Author(s):  
M. L. Martin ◽  
M. Y. Luna ◽  
F. Valero
Keyword(s):  
Diabatic Heating ◽  
Potential Temperature ◽  
Principal Component ◽  
Phase Changes ◽  
Synoptic Scale ◽  
Thermodynamic Variable ◽  
Dynamic Forcing ◽  
Diabatic Forcing

Abstract. The quasigeostrophic theory is used to address the role of diabatic forcing in synoptic scale processes over Iberia. A parametrization of diabatic heating is obtained in terms of a thermodynamic variable called the ice-liquid water potential temperature which is conservative under all phase changes of water. A case study objectively selected by means of a rotated principal component analysis over the diabatic field is analyzed to test the proposed parametrization. This study highlights the fact that the magnitudes of diabatic forcing and dynamic forcing are very nearly the same throughout the troposphere. The results also show that the composite diabatic heating is a better representation for both cloudiness and precipitation fields than the dynamic forcing.

SenCity – Evaluating Users’ Experiences of Intelligent Lighting for Well-Being in Smart Cities

2018 ◽  
pp. 60-67
Author(s):  
Henrika Pihlajaniemi ◽  
Anna Luusua ◽  
Eveliina Juntunen
Keyword(s):  
Case Studies ◽  
Smart City ◽  
Smart Cities ◽  
Well Being ◽  
Evaluation Methods ◽  
Data Analyses ◽  
Sense Of Security ◽  
System Data

This paper presents the evaluation of usersХ experiences in three intelligent lighting pilots in Finland. Two of the case studies are related to the use of intelligent lighting in different kinds of traffic areas, having emphasis on aspects of visibility, traffic and movement safety, and sense of security. The last case study presents a more complex view to the experience of intelligent lighting in smart city contexts. The evaluation methods, tailored to each pilot context, include questionnaires, an urban dashboard, in-situ interviews and observations, evaluation probes, and system data analyses. The applicability of the selected and tested methods is discussed reflecting the process and achieved results.

Site specific agricultural soil management with the use of new technologies

2013 ◽  
Vol 16 (1) ◽  
pp. 59-67
Keyword(s):  
New Technologies ◽  
Digital Interface ◽  
Appropriate Treatment ◽  
Wide Range ◽  
Soil Variation ◽  
Soil Information ◽  
Remote Sensing Techniques ◽  
Agricultural Areas

<p>The Soil Science Institute of Thessaloniki produces new digitized Soil Maps that provide a useful electronic database for the spatial representation of the soil variation within a region, based on in situ soil sampling, laboratory analyses, GIS techniques and plant nutrition mathematical models, coupled with the local land cadastre. The novelty of these studies is that local agronomists have immediate access to a wide range of soil information by clicking on a field parcel shown in this digital interface and, therefore, can suggest an appropriate treatment (e.g. liming, manure incorporation, desalination, application of proper type and quantity of fertilizer) depending on the field conditions and cultivated crops. A specific case study is presented in the current work with regards to the construction of the digitized Soil Map of the regional unit of Kastoria. The potential of this map can easily be realized by the fact that the mapping of the physicochemical properties of the soils in this region provided delineation zones for differential fertilization management. An experiment was also conducted using remote sensing techniques for the enhancement of the fertilization advisory software database, which is a component of the digitized map, and the optimization of nitrogen management in agricultural areas.</p>

scholarly journals System Dynamics-Multiple Objective Optimization Model for Water Resource Management: A Case Study in Jiaxing City, China

Water ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 671
Author(s):  
Xiaoying Zhou ◽  
Feier Wang ◽  
Kuan Huang ◽  
Huichun Zhang ◽  
Jie Yu ◽  
...  
Keyword(s):  
Resource Management ◽  
System Dynamics ◽  
Water Resource ◽  
Water Allocation ◽  
Water Resource Management ◽  
Water Shortage ◽  
Multiple Objective ◽  
Multiple Objective Optimization ◽  
Model Framework

Predicting and allocating water resources have become important tasks in water resource management. System dynamics and optimal planning models are widely applied to solve individual problems, but are seldom combined in studies. In this work, we developed a framework involving a system dynamics-multiple objective optimization (SD-MOO) model, which integrated the functions of simulation, policy control, and water allocation, and applied it to a case study of water management in Jiaxing, China to demonstrate the modeling. The predicted results of the case study showed that water shortage would not occur at a high-inflow level during 2018–2035 but would appear at mid- and low-inflow levels in 2025 and 2022, respectively. After we made dynamic adjustments to water use efficiency, economic growth, population growth, and water resource utilization, the predicted water shortage rates decreased by approximately 69–70% at the mid- and low-inflow levels in 2025 and 2035 compared to the scenarios without any adjustment strategies. Water allocation schemes obtained from the “prediction + dynamic regulation + optimization” framework were competitive in terms of social, economic and environmental benefits and flexibly satisfied the water demands. The case study demonstrated that the SD-MOO model framework could be an effective tool in achieving sustainable water resource management.

scholarly journals An Improved Algorithm for Measuring Nitrate Concentrations in Seawater Based on Deep-Ultraviolet Spectrophotometry: A Case Study of the Aoshan Bay Seawater and Western Pacific Seawater

Sensors ◽  
2021 ◽  
Vol 21 (3) ◽  
pp. 965
Author(s):  
Xingyue Zhu ◽  
Kaixiong Yu ◽  
Xiaofan Zhu ◽  
Juan Su ◽  
Chi Wu
Keyword(s):  
Weighted Average ◽  
Measuring Method ◽  
Western Pacific ◽  
Nitrate Concentrations ◽  
Deep Ultraviolet ◽  
Ultraviolet Spectrometer ◽  
Seawater Samples ◽  
Reflection Probe

Nowadays, it is still a challenge for commercial nitrate sensors to meet the requirement of high accuracy in a complex water. Based on deep-ultraviolet spectral analysis and a regression algorithm, a different measuring method for obtaining the concentration of nitrate in seawater is proposed in this paper. The system consists of a deuterium lamp, an optical fiber splitter module, a reflection probe, temperature and salinity sensors, and a deep-ultraviolet spectrometer. The regression model based on weighted average kernel partial least squares (WA-KPLS) algorithm together with corrections for temperature and salinity (TSC) is established. After that, the seawater samples from Western Pacific and Aoshan Bay in Qingdao, China with the addition of various nitrate concentrations are studied to verify the reliability and accuracy of the method. The results show that the TSC-WA-KPLS algorithm shows the best results when compared against the multiple linear regression (MLR) and ISUS (in situ ultraviolet spectrophotometer) algorithms in the temperatures range of 4–25 °C, with RMSEP of 0.67 µmol/L for Aoshan Bay seawater and 1.08 µmol/L for Western Pacific seawater. The method proposed in this paper is suitable for measuring the nitrate concentration in seawater with higher accuracy, which could find application in the development of in-situ and real-time nitrate sensors.

scholarly journals Laboratory-Scale Processing and Performance Assessment of Ti–Ta High-Temperature Shape Memory Spring Actuators

2021 ◽  
Author(s):  
A. Paulsen ◽  
H. Dumlu ◽  
D. Piorunek ◽  
D. Langenkämper ◽  
J. Frenzel ◽  
...  
Keyword(s):  
High Temperature ◽  
Shape Memory ◽  
Detrimental Effect ◽  
Wire Drawing ◽  
Fast Heating ◽  
Heating And Cooling ◽  
Arc Melting ◽  
Ω Phase ◽  
And Performance

AbstractTi75Ta25 high-temperature shape memory alloys exhibit a number of features which make it difficult to use them as spring actuators. These include the high melting point of Ta (close to 3000 °C), the affinity of Ti to oxygen which leads to the formation of brittle α-case layers and the tendency to precipitate the ω-phase, which suppresses the martensitic transformation. The present work represents a case study which shows how one can overcome these issues and manufacture high quality Ti75Ta25 tensile spring actuators. The work focusses on processing (arc melting, arc welding, wire drawing, surface treatments and actuator spring geometry setting) and on cyclic actuator testing. It is shown how one can minimize the detrimental effect of ω-phase formation and ensure stable high-temperature actuation by fast heating and cooling and by intermediate rejuvenation anneals. The results are discussed on the basis of fundamental Ti–Ta metallurgy and in the light of Ni–Ti spring actuator performance.

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