Heat Distribution Pattern Research Articles

Heat Distribution Simulation in a Square Aluminum 7075 Plate Using Laplace Equation and MATLAB

The efficient management of heat transfer from aircraft engines to the wings is vital for maintaining thermal efficiency and structural integrity in modern aircraft design. Excessive heating of the wings, caused by engine-generated heat, can negatively impact aerodynamic performance and safety. This study focuses on analyzing heat distribution in a square aluminum 7075 plate to better understand heat transfer mechanisms. Using the Laplace equation, implemented through MATLAB (2023 Online Version), we aim to simulate and analyze heat distribution on the plate. The numerical method employed in this research involves solving the Laplace equation with Neumann boundary conditions, which represent insulated edges. The Liebmann method is used to iteratively reduce error to less than 1%. Simulations are conducted on an aluminum 7075 plate of dimensions 4x10⁻² m x 4x10⁻² m under various temperature conditions at the edges. Numerical results show that at the 9th iteration, the error reaches 0.71%, while MATLAB simulations yield an error of 0.4681% at the same iteration. The heat distribution across the plate is clearly visualized, and the analysis indicates that increasing the number of grids improves both the clarity and accuracy of the simulation results. In conclusion, this study demonstrates that applying the Laplace equation via MATLAB is an effective approach for analyzing heat distribution in aluminum 7075 plates. The results show that a finer grid resolution enhances accuracy, with a 101-grid system providing particularly clear and precise heat distribution patterns. These findings contribute to the optimization of thermal system designs, especially in aviation-related applications.

China coasts facing more tropical cyclone risks during the second decaying summer of double-year La Niña events

Long-lasting La Niña events (including double-year and triple-year La Niña events) have become more frequent in recent years. How the multi-year La Niña events affect tropical cyclone (TC) activities in the western North Pacific (WNP) and whether they differ from single-year La Niña events are unknown. Here we show that TCs are more active over the far-WNP (FWNP, 110°–150°E), leading to marked high risks at China coasts during the second decaying summer of double-year La Niña events. The anomalous TC activities are directly related to the enhanced cyclonic anomaly over the FWNP, possibly a result of large-scale remote forcing initiated by the tropical North Atlantic (TNA) cooling. The persistent TNA cooling from the decaying winter to summer of double-year La Niña events drives westerlies over the Indo-western Pacific through Kelvin waves, which induce the cooling over the north Indian Ocean via the wind-evaporation-sea surface temperature effect, favoring the asymmetric heat distribution pattern and stimulating an anomalous vertical circulation over the eastern Indian Ocean to FWNP. The cooling over the north Indian Ocean also excites Gill responses, magnifying the TNA-induced westerlies and boosting the anomalous vertical circulation, and thus gives rise to the strong cyclonic circulation anomaly over the FWNP in summer. We suggest that the key point of the process is the strong TNA cooling related to the persistent negative Pacific-North American pattern (PNA) and positive North Atlantic Oscillation (NAO) while double-year La Niña events decay, distinct from the rapid decline of PNA and NAO during single-year La Niña events. The work provides a unique perspective on understanding TC activities over the WNP related to the El Niño-Southern Oscillation.

Comparative Analysis for Titanium alloy and Silicon Nitride (Si3N4) of Thermal Analysis for Deep Groove Ball Bearing

In this paper, the analysis of the directional heat flux and total heat flux for the bearing balls of Titanium alloy and Silicon Nitride has been demonstrated across a temperature range between 150 to 250 degree celcius. The obtained data allowed comparing the values of total heat flux and various directional heat flux. By comparing directional and total flux of heat in materials it enables the choice of the best-suited material creating bearings with regard to the performance needed. The use of the findings of the current comparison is to ensure efficiency and durability in particular operations. The data presented in the paper helped to analyze the patterns of heat distribution and see the differences between the materials and results a better material for ball bearing. Titanium alloy has excellent mechanical properties like mechanical strength and corrosion resistance. Silicon Nitride is characterized by thermal stability and high thermal resistance and also has excellent wear properties. Thus, using the results of the analysis allows choosing the material for bearing production for high-velocity and high-load operation based on a profound comparison to select the right material. The choice of right material will allow for a more efficient and durable bearing in an industrial setting.

An efficient artificial gorilla troops optimizer-based tracker for harvesting maximum power from thermoelectric generation system

The thermoelectric generator (TEG) device opens a new lighted avenue for saving waste heat by transferring it into electrical energy. Due to the unique features of the TEG systems, they have materialized as promising alternatives for green power production. Nonetheless, the TEG generated power is mainly influenced by the distribution of temperature levels added to the value of the load. To enhance the utilization efficiency of the TEG, proposing a reliable maximum power point tracker (MPPT) approach to detect the maximum global power of it is an essential solution. Two remarkable drawbacks are detected in the conventional MPPT, low dynamic response and high oscillations around MPP. Also, operating the TEG system at non-uniform heat distribution generates multi-local peaks in the TEG system characteristic which is difficult to be monitored by traditional trackers. Therefore, this paper proposes an efficient artificial gorilla troops optimizer (GTO) to simulate MPPT with TEG array operated at various temperature distribution conditions. The proposed approach is examined on 9 × 9 and 15 × 15 TEG arrays operated at seven cases including normal, non-uniform row, non-uniform column, long wide, diagonal, internal, and random temperature distributions. For investigating the proposed approach performance versus the state-of-the-art techniques, set of MPPT approaches including comparison to incremental resistance (INR), particle swarm optimizer (PSO), seagull optimization algorithm (SOA), and cuckoo search (CS) have been implemented under the same case studies. The comparisons reveal the superiority of the proposed GTO-MPPT in monitoring the peak global harvested power in time less than 1 s. The SOA is located at the second rank after GTO in the fetched power and the time consumed for achieving the steady state operation. Meanwhile, the INR, PSO, and CS fall in local maximum power points. Moreover, for 9 × 9 array, the minimum error between the simulink model and the proposed GTO-MPPT is 0.01% at internal heat distribution pattern while it is 0.09% for 15 × 15 array at normal operation. The results proved the efficiency of employing the GTO-MPPT compared to the other considered methods.

Thermal imaging in rheumatoid arthritis knee joints and its correlation with power Doppler ultrasound

BackgroundPower Doppler ultrasound (PDUS) is an established non-invasive modalities for quantification of inflammation, which has a bearing on the assessment of disease activity in rheumatoid arthritis (RA). However, PDUS has several disadvantages including cost of equipment, steep learning curve and inter-observer variability. Thermal imaging has emerged as a simple, powerful tool for mapping the heat distribution pattern and has the potential to document and quantify disease activity in RA. The objective was to study the thermal imaging pattern of inflamed knee joints in cases of RA and its correlation with PDUS. MethodsThis pilot case-control study was carried out at the rheumatology centre in India including 100 subjects (50 controls and 50 RA patients). All participants underwent thermal imaging and PDUS for the knee joints. The mean temperatures in area of interest in knee, thigh and knee–thigh differential were analysed in comparison with PDUS findings. ResultsRA subjects had significantly higher mean knee temperature and mean knee–thigh temperature differential compared with controls (p value < 0.00001). PDUS documented inflammation strongly correlated with knee–thigh temperature differential. ConclusionThere was a statistically significant difference in mean knee temperature as well as mean knee–thigh temperature differential of inflamed versus control knees. Thermal imaging has the potential to become simple, objective, cost-effective and reliable tool for diagnosis and assessment of disease activity in inflammatory arthritis.

Thermal heat distribution features for hand identification

Thermal imaging is a non-invasive and portable technique with growing use in medical and authentication applications. This research utilizes thermal images for hand identification. Existing hand identification methods mainly extract geometric features, such as the palm’s and fingers’ absolute sizes and ratios. In this work, subject identification based on spatial statistical thermal distribution features is examined. These features do not depend on the geometric shape of the hand, but rather capture only physiological properties and convert them to statistical features. Thus, our goal is to evaluate the ability to identify a hand by characterizing the thermal heat distribution pattern, without relaying on geometric proprieties.A novel image processing algorithm, which identifies and locates the hand posture from the image and extracts several features from 15 locations in the hand, was developed. Then, dimensionality reduction methods are applied to form a compact model of the data. The best model was selected based on the clustering quality. Classification of a single subject out of many resulted with accuracy of 94%. Classification of many subjects simultaneously resulted with accuracy of 91%. Identification of new image data is carried out in this low-dimensional space and results with an accuracy of 94%. In addition, the low-dimensional representation was used to explore time and environmental factors, which were found to have a low impact on the coded data, thus promoted the suitability of the proposed method.

A Microwave-Thermography Hybrid Technique for Breast Cancer Detection

This paper proposes a hybrid breast cancer detection modality consisting of microwaves as a radiation source and an infrared thermography method as a heat-imaging recorder, supported by a Convolution Neural Network (CNN). This hybrid method is based on the difference in the transmitted electromagnetic power between healthy and tumorous breasts. This variation in transmitted power results from the electrical property variance between healthy and cancerous tissues. Under microwave radiation, the power of the transmitted waves leads to a heat distribution pattern on a sensitive screen placed under the breast. This work utilizes the change in the heat pattern to indicate the presence of abnormality inside the breast. Involving a CNN elevates the proposed technique’s detection capability and extracts quantitative data that characterize the tumor’s location and size. The proposed modality shows a capability to detect and determine the size and location of an artificial tumor with a 5 mm radius and a 2:1 permittivity contrast with normal tissue.

Retraction Note: Mountain atmospheric characteristics based on 5G big data and Yunnan minority pattern design

With the constantly updated new technologies and application software and the 5G big data era that is gradually moving to the market, big data as a modern technological resource has gradually developed in terms of conversion conditions and methods, and it is more convenient to transform from abstraction to reality, which is a mountainous atmosphere detection zone. There are new opportunities and challenges. Therefore, in the context of 5G big data, discussing how to improve the ability of mountain atmospheric observation has certain theoretical value and practical significance. The atmospheric characteristics of the mountain refer to the heat (warming) generated by the uplifted land. The altitude of the mountain/plateau changes the heat distribution pattern of the mountain and its surrounding area, and raises the internal temperature of the mountain to be higher than the surrounding open air temperature at the same altitude. Horizontal pattern is observed, thus forming a vertical pattern in which the inside of the natural area is higher than the outside. The quantification of mountain effects is the key to solving the problem of no belts in vertical mountainous areas. The country must promote its legacy and make it widely known. A basic element of modern pattern design is the pattern design of Yunnan ethnic minorities, which is a medium for expressing cultural heritage. This part of the pattern design of ethnic minorities includes profound ancient cultural and esthetic characteristics, rich in national colors. Relying on the application of Yunnan ethnic minority folk art patterns in contemporary art design, it demonstrates leading the ethnic cultural personality decoration trend, promoting the diversification of contemporary design styles, fully reflecting the natural customs and human factors and other aspects, and discussing the Yunnan ethnic folk art pattern spiritual essence. Based on the actual demands of contemporary pattern design, analyzing the actual application of Yunnan ethnic and folk art patterns plays an important role in the development of the field of Chinese art design.

RETRACTED ARTICLE: Mountain atmospheric characteristics based on 5G big data and Yunnan minority pattern design

With the constantly updated new technologies and application software and the 5G big data era that is gradually moving to the market, big data as a modern technological resource has gradually developed in terms of conversion conditions and methods, and it is more convenient to transform from abstraction to reality, which is a mountainous atmosphere detection zone. There are new opportunities and challenges. Therefore, in the context of 5G big data, discussing how to improve the ability of mountain atmospheric observation has certain theoretical value and practical significance. The atmospheric characteristics of the mountain refer to the heat (warming) generated by the uplifted land. The altitude of the mountain/plateau changes the heat distribution pattern of the mountain and its surrounding area, and raises the internal temperature of the mountain to be higher than the surrounding open air temperature at the same altitude. Horizontal pattern is observed, thus forming a vertical pattern in which the inside of the natural area is higher than the outside. The quantification of mountain effects is the key to solving the problem of no belts in vertical mountainous areas. The country must promote its legacy and make it widely known. A basic element of modern pattern design is the pattern design of Yunnan ethnic minorities, which is a medium for expressing cultural heritage. This part of the pattern design of ethnic minorities includes profound ancient cultural and esthetic characteristics, rich in national colors. Relying on the application of Yunnan ethnic minority folk art patterns in contemporary art design, it demonstrates leading the ethnic cultural personality decoration trend, promoting the diversification of contemporary design styles, fully reflecting the natural customs and human factors and other aspects, and discussing the Yunnan ethnic folk art pattern spiritual essence. Based on the actual demands of contemporary pattern design, analyzing the actual application of Yunnan ethnic and folk art patterns plays an important role in the development of the field of Chinese art design.

Heat transfer measurements of a turbine endwall with engine-representative freestream turbulence and inlet swirl

ABSTRACT Flow distortions from upstream combustors generate various and significant changes to the patterns of endwall heat transfer for an aircraft engine. In this study, to model engine-representative oncoming flows into the high-pressure turbine, turbulence and swirl generators are carefully designed at the inlet of a linear turbine cascade. Detailed heat transfer characteristics over the endwall are measured by using a steady thermochromic liquid crystal (TLC) method for various Reynolds numbers. Comparisons with a baseline case that has no upstream turbulence or swirl generators show that both turbulence and inlet swirl alter the heat transfer levels and distribution patterns, but their mechanism of action differs from one another. The turbulence alters the heat transfer by thinning the inlet boundary layer, while the inlet swirl generates the changed heat transfer due to the sweep effects of the swirl on the endwall, resulting in a much higher heat transfer enhancement than that by the turbulence. Additionally, the highest enhancement for both cases is found at the low Reynolds number of 1.0 × 105 and higher Reynolds numbers yield to a reduced enhancement. Specially, compared to the turbulence case, the enhancement by the inlet swirl drops much more rapidly, indicating that the inlet swirl effects have stronger links to the Reynolds number.

Distribution patterns of tau pathology in progressive supranuclear palsy

Progressive supranuclear palsy (PSP) is a 4R-tauopathy predominated by subcortical pathology in neurons, astrocytes, and oligodendroglia associated with various clinical phenotypes. In the present international study, we addressed the question of whether or not sequential distribution patterns can be recognized for PSP pathology. We evaluated heat maps and distribution patterns of neuronal, astroglial, and oligodendroglial tau pathologies and their combinations in different clinical subtypes of PSP in postmortem brains. We used conditional probability and logistic regression to model the sequential distribution of tau pathologies across different brain regions. Tau pathology uniformly predominates in the neurons of the pallido-nigro-luysian axis in different clinical subtypes. However, clinical subtypes are distinguished not only by total tau load but rather cell-type (neuronal versus glial) specific vulnerability patterns of brain regions suggesting distinct dynamics or circuit-specific segregation of propagation of tau pathologies. For Richardson syndrome (n = 81) we recognize six sequential steps of involvement of brain regions by the combination of cellular tau pathologies. This is translated to six stages for the practical neuropathological diagnosis by the evaluation of the subthalamic nucleus, globus pallidus, striatum, cerebellum with dentate nucleus, and frontal and occipital cortices. This system can be applied to further clinical subtypes by emphasizing whether they show caudal (cerebellum/dentate nucleus) or rostral (cortical) predominant, or both types of pattern. Defining cell-specific stages of tau pathology helps to identify preclinical or early-stage cases for the better understanding of early pathogenic events, has implications for understanding the clinical subtype-specific dynamics of disease-propagation, and informs tau-neuroimaging on distribution patterns.

Thermal energy storage based (TES-based) reverse cycle defrosting control strategy optimization for a cascade air source heat pump

Thermal energy storage based (TES-based) reverse cycle defrosting method is a feasible way to reduce energy requirements for defrosting of cascade air source heat pumps (CASHPs). The energy stored in the phase change material based heat exchanger (PCM-HE) is the heat source for both the high stage cycle (HSC) and low stage cycle (LSC) during the TES-based reverse cycle defrosting process, thus the heat provided to the HSC and LSC are coupled, affecting the defrosting performance in LSC and heating performance in HSC. To shorten the defrosting time and maintain the indoor thermal environment, the heat distribution between HSC and LSC during TES-based reverse cycle defrosting was explored. It was found that the heat distribution pattern was mainly influenced by the refrigerant flowrate. Therefore, controlling the refrigerant flowrate of HSC and LSC during the TES-based reverse cycle defrosting is a possible way to regulate the heat distribution between HSC and LSC. In this paper, an experimental investigation of the control strategy for TES-based reverse cycle defrosting of CASHPs is presented. The defrosting performance and indoor heating performance during TES-based defrost operation with LSC compressor frequencies of 60 Hz, 75 Hz, 90 Hz, and 105 Hz were tested. Then HSC EEV openings of 80%, 90% and 100% at the optimized LSC compressor frequency of 90 Hz were considered. It was concluded that the optimal TES-based reverse cycle defrosting strategy is to maintain the LSC compressor frequency at 90 Hz and the HSC EEV opening at 80% for the equipment considered in this study. The defrosting time was 440 s and the average indoor heating capacity was 5.23 kW. The heat provided to the HSC and LSC accounted for 38.7% and 61.3% of the total heat released by PCM-HE, respectively.

Feasibility test of Dynamic Cooling for detection of small tumors in IR thermographic breast imaging

Abstract Thermographic imaging is a known technology to detect temperature differences. For medical applications, the patterns of heat distribution are used for diagnosis. It is already tested to visualize blood supply, inflammatory processes, and superficial or more extensive tumors, e.g. in the breast tissue. This method was promoted for breast screening purposes and as a substitute for mammography for mid aged women, but the results were not convincing for younger women, where tissue density is higher, tumor growth is often connected to local temperature increase and radiation-based mammography is not an option. Infrared (IR) thermography can support tumor screening. The screening should allow the early detection of small lesions even in the depth. Therefor we evaluated the feasibility of dynamic cooling in combination with IR imaging in a phantom study. A temperature-controllable gel phantom including a heating plate, a depth-adjustable heat source mimicking a tumor, and three sensors for temperature monitoring was built up. A raspberry pi device serves as a control unit to create a stable temperature balance comparable to a human breast. For the experiments, the tumor was placed in various depth. After cooling, the thermal recovery phase of the phantom was imaged using an IR camera and a webcam. A pixel-wise analysis of the IR data detects a higher gradient of temperature change in the tumor region. The experiments demonstrated the feasibility of tumor detection based on dynamic cooling and IR imaging.

Top oil heat distribution pattern of ONAN corn oil based transformer with presence of hot spot study using FEMM

Transformer thermal modelling is a crucial aspect to be considered as this may help the determination of heat capacity of transformer. This paper present, simulation study on Oil Natural Air Natural (ONAN) transformer heat distribution pattern with and without presence of hot spot temperature (HST). This paper aims to compare the effects of different HST value at different locations inside the transformer unit as well as to evaluate the top oil thermal behaviour of corn oil as cooling mechanism in a transformer. To achieve aforementioned objectives, three HSTs were introduced to the 30 MVA transformer winding to find the total heat build-up in the top of the transformer tank. The outcome of thermal properties is examined using x-y temperature plot. From the results found that the location of HST affects overall transformer’s temperature. HST at the top of the winding give a significant effect compared to when HST is at the bottom of the winding. It is also evident that the usage of corn oil reduced the temperature distribution of the transformer. The findings suggest that the temperature distribution study especially on transformer is important to monitor in-service transformer in a non-invasive manner.

The ‘Air-Wall’: Re-Evaluating a Mid-Twentieth Century Four-Sided Double-Skin Façade

In the 1950s, architect William Hajjar built a four-story research building with a two-story double-skin facade (DSF) on all four building sides with the intention to explore solar heat control strategies: in winter, the movement of warm air from sun-exposed DSFs toward the cold sides to reduce heating loads, and in summer, the removal of the DSF’s warm air to reduce cooling loads. The article presents archival studies, computational fluid dynamics simulations, and smoke experiments, all undertaken to explore the performance of four-sided DSFs with regard to heat distribution and airflow patterns in winter. The studies confirm the potentials to create a temperature equilibrium around the facade and reduce heating loads. However, excessive heat build-up in the DSFs on clear days remains challenging.

Study on Testing Environment Simulation Method for Thermal Flux Density of Aerothermal

This paper presents the use of forced convection heat transfer approach to near-space thermal environment of hypersonic aerodynamic ground simulation test method for surface heat flux with a great gradient and temperature gradient of the tip wedge (rn=1.5mm) shape component level thermal test. In the test device test section, two different high subsonic speed airflow were nested within each of the two vents from the exhaust, the impact of the specimen heated to test sharp wedge surface heat flow and temperature distribution in line with a hypersonic flight state aerodynamic heat distribution patterns. Numerical results show that under this scenario, the specimen rear stagnation point heat flux and heat flux can be adjusted two ways to adjust the air flow; test methods within a certain accuracy-related parts for the superb aerodynamic vehicle thermal environment simulation.

Numerical simulation of the impact of geological heterogeneity on performance and safety of THAI heavy oil production process

The Toe-to-Heel Air Injection (THAI) in-situ combustion process is an efficient way to extract heavy oil and bitumen. However, such reservoirs are often geologically heterogeneous. This work studied the impact of a range of different geological heterogeneities, often found in bitumen deposits, on the performance and safety of THAI. These heterogeneities included random heterogeneity, layered reservoirs, shaly reservoirs, and semi-permeable cap-rocks. A further aim was to also develop potential remedial measures, such as selective well placement. It was found that the degree of symmetry assumed for the reservoir model had a substantial impact on the predicted level of oil production. This is of particular relevance to otherwise apparently symmetrical well placement designs such as staggered line drive. While the presence of impermeable zones resulted in the decrease in the overall oxygen utilisation for shaly reservoirs, compared to simply low permeability reservoirs, there was no evidence of oxygen breakthrough due to preferential channelling into the production well. In layered reservoirs, the development of a rich oil bank during THAI operation depended upon the distribution of permeability around the horizontal producer (HP), and did not occur when there was high permeability just above the HP. It has been shown that the proper representation of the cap-rock in reservoir models for the simulation of THAI is essential in order to accurately mimic the full pattern of heat distribution into the oil zone of the reservoir, and, thence, fuel lay-down. While THAI can operate stably with a permeable cap-rock, vertical permeabilities above ∼1–3 mD led to significant loss of combustion gases from the reservoir.

Influences of multiple layers of air temperature differences on tidal forces and tectonic stress before, during and after the Jiujiang earthquake

Using the air temperature data of the National Center for Environmental Prediction (NCEP), we compared multiple layers of air temperature differences before, during and after the Jiujiang earthquake, and explored its relationship with the additive tectonic stress caused by celestial tide-generating force (ATSCTF). The earthquake occurred at the 1 of 4 high phases of ATSCTF, while the temperature rise came from land surface to high sky. It indicated that the tide force could trigger an earthquake when the tectonic stress was in critical status, and the air temperature rise reflected the terra stress change modulated under the tidal force. During the shock period of ATSCTF, the distribution of air temperature changes both near land surfaces and upper multi-layers along the active fault zones showed a tectonic disturbance pattern of calm before earthquake, rise during earthquake, calm after earthquake as well as a heat distribution pattern of the surface air warmed by land, uplifted by heat flux, cooled and dissipated in the sky. The pattern of changes obeyed the rule of thermal rise of rocks broken under stress loading and the principle of atmospheric thermal dynamic diffusion in vertical. We argued that an earthquake may also be a reason for air temperature differences rather than a simple weather process. At the same time, the rise of air temperature was synchronized with the ATSCTF fluctuant, which showed that tidal force had a particular indicative significance for the identification of temperature anomaly on seismic faults. Because of the mechanical characteristics of the study of earthquake thermal anomalies, it could help to identify the earthquake thermal anomalies and the climatic thermal anomalies, and provided a clear time-indication for the choice of the background temperature in the seismic thermal anomaly recognition.

Contributions of Interdecadal Pacific Oscillation and Atlantic Multidecadal Oscillation to Global Ocean Heat Content Distribution

Abstract Regional sea surface temperature (SST) mode variabilities, especially the La Niña–like Pacific Ocean temperature pattern known as the negative phase of the interdecadal Pacific oscillation (IPO) and the associated heat redistribution within the ocean, are the leading mechanisms explaining the recent global warming hiatus. Here version 1 of the Community Earth System Model (CESM) is used to examine how different phases of two leading decadal time scale SST modes, namely the IPO and the Atlantic multidecadal oscillation (AMO), contribute to heat redistribution in the global ocean in the absence of time-evolving external forcings. The results show that both the IPO and AMO contribute a similar magnitude to global mean surface temperature and ocean heat redistribution. Both modes contribute warmer surface temperature and higher upper ocean heat content in their positive phase, and the reverse in their negative phase. Regionally, patterns of ocean heat distribution in the upper few hundred meters of the tropical and subtropical Pacific Ocean depend highly on the IPO phase via the IPO-associated changes in the subtropical cell. In the Atlantic, ocean heat content is primarily associated with the state of the AMO. The interconnections between the IPO, AMO, and global ocean heat distribution are established through the atmospheric bridge and the Atlantic meridional overturning circulation. An in-phase variant of the IPO and AMO can lead to much higher surface temperatures and heat content changes than an out-of-phase variation. This result suggests that changes in the IPO and AMO are potentially capable of modulating externally forced SST and heat content trends.

Evaluation of Thermal Imaging in the Diagnosis and Classification of Varicocele

Introduction: A varicocele is the abnormal dilation and tortuosity of venous plexus above the testicles. The pattern of abnormal heat distribution in the scrotum can be detected through thermal imaging, which is a distant, non-contact, and non-invasive method. The aim of the present study is to detect and grade varicocele. Materials and Methods: This study was conducted on 50 patients with high probability of varicocele, who referred to a hospital affiliated to the AJA University of Medical Sciences, Tehran, Iran. The evaluation procedure included thermal imaging, clinical diagnosis, and ultrasound test. The gold standard method was based on ultrasound examination. The thermal imaging was performed using a non-contact infrared camera. Results: This paper presented two methods for diagnosing and grading varicocele. The first method was based on the patterns and models of thermal asymmetry in the testicles (including three asymmetric and symmetric patterns). The second method was based on the temperature differences. The obtained results demonstrated that the use of temperature differences in the diagnosis of varicocele was better than the other proposed method. In addition, a temperature difference of 0.5°C in the pampiniform venous plexus was an important indicator for the diagnosis of varicocele using thermal imaging. The accuracy of thermography in grading varicocele was 76%. Conclusion: According to the results of the study, thermography is a useful method for initial varicocele screening and can be applied as a supplement to other diagnostic techniques due to its low cost and lack of radiation exposure. Thermography was concluded to be a precise technique for the diagnosis of varicocele; however, its capability to determine the varicocele grading was comparatively low.