Impact of Varying Blower Opening Degrees on Indoor Environment and Thermal Comfort

At present,air handling units are usually used indoors to improve the indoor environment quality.However,while introducing fresh air to improve air quality,air velocity has a certain impact on the occupants’thermal comfort.Therefore,it is necessary to explore the optimization of air-fluid-body interaction dynamics.In this study,the indoor air flow was changed by changing the opening and closing degree of the blower,and the thermal manikin is introduced to objectively evaluate the human thermal comfort under different air velocities.The main experimental results show that the air change rate increases with the increase of the opening and closing degree of the blower considering an ACH(air changes per hour)range between 3.8 and 10.For a better prediction,a linear correlation with a coefficient of 0.995 is proposed.As the blower’s opening is adjusted to 20%,25%,30%,35%,and 40%,the air velocity sensor positioned directly beneath the air inlet records average velocities of 0.19,0.20,0.21,0.28,and 0.34 m/s over four hours,respectively.Observations on thermal comfort and the average sensation experienced by individuals indicate an initial increase followed by a decline when the blower’s operation begins,with optimal conditions achieved at a 35%opening.These findings offer valuable insights for future indoor air ventilation and heat transfer design strategies.

Rapid correction of hyperglycemia:A necessity but at what price?A brief report of a patient living with type 1 diabetes

BACKGROUND The correction and control of chronic hyperglycemia are the management goals of patients living with diabetes.Chronic hyperglycemia is the main factor inducing diabetes-related complications.However,in certain situations,the rapid and intense correction of chronic hyperglycemia can paradoxically favor the onset of microvascular complications.CASE SUMMARY In this case report,we describe the case of a 25-year-old woman living with type 1 diabetes since the age of 9 years.Her diabetes was chronic and unstable but without complications.During an unplanned pregnancy,her diabetes was intensely managed with the rapid correction of her hyperglycemia.However,over the following 2 years,she developed numerous degenerative microvascular complications:Charcot neuroarthropathy with multiple joint involvement,severe proliferative diabetic retinopathy,gastroparesis,bladder voiding disorders,and end-stage renal failure requiring hemodialysis.CONCLUSION In the literature to date,the occurrence of multiple microvascular complications following the rapid correction of chronic hyperglycemia has been rarely described in the same individual.

Impact of Radiation and Slip on Newtonian Liquid Flow Past a Porous Stretching/Shrinking Sheet in the Presence of Carbon Nanotubes

The impacts of radiation,mass transpiration,and volume fraction of carbon nanotubes on the flow of a Newtonian fluid past a porous stretching/shrinking sheet are investigated.For this purpose,three types of base liquids are considered,namely,water,ethylene glycol and engine oil.Moreover,single and multi-wall carbon nanotubes are examined in the analysis.The overall physical problem is modeled using a system of highly nonlinear partial differential equations,which are then converted into highly nonlinear third order ordinary differential equations via a suitable similarity transformation.These equations are solved analytically along with the corresponding boundary conditions.It is found that the carbon nanotubes can significantly improve the heat transfer process.Their potential application in cutting-edge areas is also discussed to a certain extent.

Optimization of a dynamic uncertain causality graph for fault diagnosis in nuclear power plant

Fault diagnostics is important for safe operation of nuclear power plants(NPPs). In recent years, data-driven approaches have been proposed and implemented to tackle the problem, e.g., neural networks, fuzzy and neurofuzzy approaches, support vector machine, K-nearest neighbor classifiers and inference methodologies. Among these methods, dynamic uncertain causality graph(DUCG)has been proved effective in many practical cases. However, the causal graph construction behind the DUCG is complicate and, in many cases, results redundant on the symptoms needed to correctly classify the fault. In this paper, we propose a method to simplify causal graph construction in an automatic way. The method consists in transforming the expert knowledge-based DCUG into a fuzzy decision tree(FDT) by extracting from the DUCG a fuzzy rule base that resumes the used symptoms at the basis of the FDT. Genetic algorithm(GA) is, then, used for the optimization of the FDT, by performing a wrapper search around the FDT: the set of symptoms selected during the iterative search are taken as the best set of symptoms for the diagnosis of the faults that can occur in the system. The effectiveness of the approach is shown with respect to a DUCG model initially built to diagnose 23 faults originally using 262 symptoms of Unit-1 in the Ningde NPP of the China Guangdong Nuclear Power Corporation. The results show that the FDT, with GA-optimized symptoms and diagnosis strategy, can drive the construction of DUCG and lower the computational burden without loss of accuracy in diagnosis.

Restricted Boltzmann machine: Recent advances and mean-field theory

This review deals with restricted Boltzmann machine(RBM) under the light of statistical physics.The RBM is a classical family of machine learning(ML) models which played a central role in the development of deep learning.Viewing it as a spin glass model and exhibiting various links with other models of statistical physics,we gather recent results dealing with mean-field theory in this context.First the functioning of the RBM can be analyzed via the phase diagrams obtained for various statistical ensembles of RBM,leading in particular to identify a compositional phase where a small number of features or modes are combined to form complex patterns.Then we discuss recent works either able to devise mean-field based learning algorithms;either able to reproduce generic aspects of the learning process from some ensemble dynamics equations or/and from linear stability arguments.

Fashion and out of fashion:appearance and disappearance of a novel nest building innovation

Background:Nests are composed of and built with different materials that are handled in specific ways. These mate?rials must initially have been used de novo before commonly being incorporated into nests. Plastic and plastic bags were invented in the 1950s, and they are widely distributed in the environment. Birds started picking up plastic from plastic used to cover farm produce such as silage, potatoes, beets and other crops for use in their nests in the 1960s.Methods:I recorded the frequency of such plastic use by the Blackbird(Turdus merula) in nests in Denmark, starting in 1966, followed by a peak in use in the 1970s and a subsequent decline.Results:Nests with plastic were initially built earlier in the season than those without plastic, indicating an associa?tion between innovation and early reproduction. Plastic use was subsequently selected against because nests with plastic suffered from higher rates of predation than nests without plastic, probably because nests with plastic were easier to locate. However, the elevated risk of nest predation only applied to outdoor nests, but not to nests inside buildings, probably because visually searching nest predators such as corvids do not enter buildings.Conclusions:These findings show that the dynamics of nest material use depend on the benefits of innovation and the fitness costs of nest predation.

Russet Sparrows spot alien chicks from their nests

Background： In coevolutionary interactions between brood parasites and their hosts, host parents are under strong selection to evolve defenses against parasitism. Egg rejection is an efficient and common defense against parasitism, although some apparently suitable hosts do not reject cuckoo eggs.Methods： Sparrows Ploceidae are widespread throughout the Old World, and they have a suitable diet for rearing cuckoos, but still they are rarely exploited by brood parasites. To solve such puzzle, we conducted artificial parasitism and cross-fostering experiments in Russet Sparrow （Posset cinnomomeus）.Results： The present study showed that Russet Sparrows have no egg recognition ability, but recognize their own nestlings and eject alien chicks or starve them to death. They may use visual cues in chick recognition, although they accept sister species Tree Sparrow （Posset montonus）.Conclusions： By rejecting nestlings of foreign species, Russet Sparrows have succeeded to escape from the brood parasitism by cuckoos and other parasites. Our studies shed light on the puzzle why some species are not utilized by cuckoo parasites as hosts,

Middleware technologies for cloud of things： a survey

The next wave of communication and applications will rely on new services provided by the Internet of Things which is becoming an important aspect in human and machines future. IoT services are a key solution for providing smart environments in homes, buildings, and cities. In the era of massive number of connected things and objects with high growth rate, several challenges have been raised, such as management, aggregation, and storage for big produced data. To address some of these issues, cloud computing emerged to the IoT as Cloud of Things （COT）, which provides virtually unlimited cloud services to enhance the large-scale IoT platforms. There are several factors to be considered in the design and implementation of a CoT platform. One of the most important and challenging problems is the heterogeneity of different objects. This problem can be addressed by deploying a suitable ＂middleware＂ which sits between things and applications as a reliable platform for communication among things with different interfaces, operating systems, and architectures. The main aim of this paper is to study the middleware technologies for CoT. Toward this end, we first present the main features and characteristics of middlewares. Next, we study different architecture styles and service domains. Then, we present several middlewares that are suitable for CoT-based platforms and finally, a list of current challenges and issues in the design of CoT-based middlewares is discussed.

In the Heart of Femtosecond Laser Induced Nanogratings: From Porous Nanoplanes to Form Birefringence

It is demonstrated that the form birefringence related to the so-called nanogratings is quantitatively correlated to the porosity-filling factor of these nanostructures. We reveal that matters surrounding the nanopores exhibit significant refractive index decrease which is likely due to the fictive temperature increase and/or the presence of a significant amount of interstitial O2. The control of the porosity was achieved by adjusting the laser pulse energy and the number of pulses/micron i.e. the overlapping rate. Applications can be numerous in fast material processing by the production of nanoporous matter, and photonics by changing the optical properties.

Experimental Study of the Diffusion of a Confined Wall Jet through a Perforated Plate: Influence of the Porosity and the Geometry

This paper investigated lateral diffusion of a confined two-dimensional wall jet (air inlet height: 5 cm) through a perforated plate. We considered two plates with porosities of and . The plates were positioned at distances of 10 cm and 20 cm below the jet inlet. The experiments were realized using 2D Laser Doppler Anemometer (LDA). Different profiles of mean and fluctuating velocities are presented. The presence of a perforated plate strongly modified the airflow pattern compared to an empty enclosure. The velocities above and below the plate depend on several parameters, including the porosity and the plate’s position relative to the inlet slot and the longitudinal position. The difference between the flow velocity above and below the plates could not be related using a universal formula that depends on these parameters. We also investigated the influence of a porous media of a height of 20 cm (a stack of spheres having a diameter of 3.75 cm) located below the perforated plate. The results highlight that the porous medium strengthens the effects of the perforated plate on the flow.

Navier Slip and Heat Transfer in a Nanofluid Due to a Stretching/Shrinking Sheet:An Analytical Study

This paper is devoted to the analysis of the heat transfer and Navier’s slip effects in a non-Newtonian Jeffrey fluid flowing past a stretching/shrinking sheet.The nanoparticles,namely,Cu and Al_(2)O_(3)are used with a water-based fluid with Prandtl number 6.272.Velocity slip flow is assumed to occur when the characteristic size of the flow system is small or the flow pressure is very small.By using the similarity transformations,the governing nonlinear PDEs are turned into ordinary differential equations(ODE’s).Analytical results are presented and analyzed for various values of physical parameters:Prandtl number,Radiation parameter,stretching/shrinking parameter and mass transpiration for the flow and heat transfer.The considered problem is relevant to various physical applications in the field of engineering,e.g.,the production of certain materials,the preparation of plastic and rubber sheets and glass blowing.It is shown that the considered nanofluid increases the thermal efficiency.The nanoparticles act as a heater by increasing the solid volume fraction and thermal radiation.Vice versa,they can act as a cooler if the strength of magnetic field is increased.The flow strength decreases by increasing the values of Deborah number.

A Review of Some Reference Analytic Solutions for the Magnetohydrodynamic Flow of Blood

A short review of some reference solutions for the magnetohydrodynamic flow of blood is proposed in this paper. We present in details the solutions of Hartmann (1937), of Vardanyan (1973) and of Sud et al. (1974). In each case, a comparison is provided with the corresponding solution for the flow without any external magnetic field, namely Poiseuille (plane or cylindrical) and Womersley. We also present a synopsis of some other solutions for people who would like to go further in this topic. The interest in MHD flow of blood may be motivated by many reasons, such as Magnetic Resonance Imaging (MRI), Pulse Wave Velocity measurement, magnetic drug targeting, tissue engineering, mechanotransduction studies, and blood pulse energy harvesting… These fundamental solutions should also be used as particular limiting cases to validate any proposed more elaborated solutions or to validate computer codes.

Metallurgical Analysis of Brake Blocks

This study focuses on the characterization of train brake blocks. The brake blocks are an essential organ of train speed control system to ensure comfort and safety to passengers and crew. However, poor quality soles can cause a premature wear of the wheels whose consequences are on the one hand, a damaged brake function, and also high repair costs. Samples were carried out on 3 different batches of brake blocks. Their metallurgical characterization consisted of a study of the hardness and microstructural analysis (microstructures and chemical analyzes) of the different samples. The results show that the hardness of some soles is greater than that of the wheel, mainly associated with a cementite microstructure. This can lead to a premature wear of the wheels at the expense of brake blocks.

Experimental and Numerical Investigation of the Diffusion of a Confined Wall Jet through a Perforated Plate

When performing numerical modeling of fluid flows where a clear medium is adjacent to a porous medium, a degree of difficulty related to the condition at the interface between the two media, where slip velocity exists, is encountered. A similar situation can be found when a jet flow interacts with a perforated plate. The numerical modeling of a perforated plate by meshing in detail each hole is most often impossible in a practical case (many holes with different shapes). Therefore, perforated plates are often modeled as porous zones with a simplified hypothesis based on pressure losses related to the normal flow through the plate. Nevertheless, previous investigations of flow over permeable walls highlight the impossibility of deducing a universal analytical law governing the slip velocity coefficient since the latter depends on many parameters such as the Reynolds number, porosity, interface structure, design of perforations, and flow direction. This makes the modeling of such a configuration difficult. The present study proposes an original numerical interface law for a perforated plate. It is used to model the turbulent jet flow interacting with a perforated plate considered as a fictitious porous medium without a detailed description of the perforations. It considers the normal and tangential effects of the flow over the plate. Validation of the model is realized through comparison with experimental data.

Angular Dependence of the Second Harmonic Generation Induced by Femtosecond Laser Irradiation in Silica-Based Glasses:Variation with Writing Speed and Pulse Energy

To control second harmonic generation (SHG) in silica-based glasses is crucial for fabricating photonic devices, such as frequency doubling waveguides. Here, we investigated SHG of laser induced nonlinear optical crystals in silica-based glasses, according to writing speed and pulse energy. We observed two regions with different probing laser polarization angular dependence: a) a well-defined cosine-like curve with period of 180° at low pulse energy (0.8 μJ) whatever the writing speed or at high pulse energy (1.4 μJ) with high writing speed (25 μm/s). This is accounted for by a well-defined texture for the nano crystals with their polar axis oriented perpendicular to the writing laser polarization;and b) a double cosine-like curve revealing a second texture of the crystals at high pulse energy (1.4 μJ) with low writing speed (5 μm/s) and with the polar axis oriented closer parallel to the writing laser polarization. Therefore, a SHG dependence on probing laser polarization angle may show high contrast by a correct choice of the writing speed and pulse energy. These results pave the way for elaboration of nonlinear optical devices.

Assessment of a Multimodal Strategy for Information and Collection of Advance Directives in a Comprehensive Cancer Center:Description of the Study Protocol

Background:Information on the possibility of drawing up Advance Directives(AD)is a necessity,and represents a major medical,ethical,and legal challenge.The difficulties are numerous,both organizational and cultural,and this is also true in the context of oncology,where ADs(and more broadly,advanced palliative care)are of critical importance.As an eminently sensitive subject,dealing with ADs(and therefore with end-of-life issues)requires both societal and medical/health-care acculturation.An institutional approach has therefore been developed,to deploy information tools,training professionals,and formalize the collection of AD.Such an approach cannot be implemented without an assessment not only of its objective results but also above all of its psychological effects,on both users(patients,family caregivers)and professionals.Methods:This longitudinal study,based on a mixed-method,interdisciplinary approach,will assess the impact of this information dissemination on AD,in terms of both potential positive and negative effects,using validated measurement methods.Thus,this study follows the 5 criteria of the RE-AIM model,designed to analyze the interest and impact of a device intended for users of the healthcare system;we will use a mixed methodology,relying on both a quantitative component(counting the number of people benefiting from the scheme,and those requesting support in drawing up their DA...,administering questionnaires),as well as a qualitative component(focus groups)which will enable us to study the subjective experiences of users,their relatives and the professionals involved in the scheme.Results:The results of this study will make it possible to determine the effects of this system of assistance in the drafting of ADs,which is currently being promoted by the legislator,but which is struggling to be implemented.

Mener des recherches pluridisciplinaires en SHS dans le domaine du cancer:quels leviers,quels freins?Conducting Multidisciplinary SHS Research in the Field of Cancer:Strengths and Barriers?

This paper summarizes the work held at the Cancéropôle Ile-de-France's annual SHS research seminar on the theme:Pluridisciplinarity and methods for SHS research in thefield of cancer.After clarifying the concepts of pluri-,inter-,and transdisciplinarité,it aimed to describe how this type of research is carried out in practice,addressing successively:the role of stakeholders and their respective positions,the need for a shared language,the various temporalities involved and task sharing,the interview and analysis methods as well as the implication of patient-researchers.It highlighted the personal qualities required to practice this type of research,such as psychologicalflexibility and adaptability,a strong desire for collaborative work,acceptance of risk,and a humble stance.

Disentangling land model uncertainty via Matrix-based Ensemble Model Inter-comparison Platform(MEMIP)

Background:Large uncertainty in modeling land carbon(C)uptake heavily impedes the accurate prediction of the global C budget.Identifying the uncertainty sources among models is crucial for model improvement yet has been difficult due to multiple feedbacks within Earth System Models(ESMs).Here we present a Matrix-based Ensemble Model Inter-comparison Platform(MEMIP)under a unified model traceability framework to evaluate multiple soil organic carbon(SOC)models.Using the MEMIP,we analyzed how the vertically resolved soil biogeochemistry structure influences SOC prediction in two soil organic matter(SOM)models.By comparing the model outputs from the C-only and CN modes,the SOC differences contributed by individual processes and N feedback between vegetation and soil were explicitly disentangled.Results:Results showed that the multi-layer models with a vertically resolved structure predicted significantly higher SOC than the single layer models over the historical simulation(1900–2000).The SOC difference between the multi-layer models was remarkably higher than between the single-layer models.Traceability analysis indicated that over 80%of the SOC increase in the multi-layer models was contributed by the incorporation of depth-related processes,while SOC differences were similarly contributed by the processes and N feedback between models with the same soil depth representation.Conclusions:The output suggested that feedback is a non-negligible contributor to the inter-model difference of SOC prediction,especially between models with similar process representation.Further analysis with TRENDY v7 and more extensive MEMIP outputs illustrated the potential important role of multi-layer structure to enlarge the current ensemble spread and the necessity of more detail model decomposition to fully disentangle inter-model differences.We stressed the importance of analyzing ensemble outputs from the fundamental model structures,and holding a holistic view in understanding the ensemble uncertainty.

2022年川渝时空复合型极端事件:一种新型气候灾害

During the summer of 2022,a parade of extremes,including heatwaves,droughts,forest fires,and heavy rainfall hit the Sichuan-Chongqing region(SCR),Southwest China(Fig.S1 online),resulting in rippling socioeconomic and environmental impacts(Fig.1).Though none of these events are uncommon to the region,their combination in such a daisy-chained fashion is unusual.Here,taking a compound event perspective,we thoroughly reviewed the unfolding of such cascading hazards,and sorted out the pathway of their impacts multiplying.This analysis unmasks previously underestimated and underappreciated vulnerability of multiple critical sectors in the energy-food-water-ecology nexus to increasingly connected extremes.Several key steps are finally outlined with the aim of improving our coping capabilities against impending spatiotemporally compound hazards.

Large electrical strain in lead-free K_(0.5)Na_(0.5)NbO_(3)-based ceramics by heterovalent doping

Heterovalent doped(K_(0.48-0.07)xNa_(0.52-0.43)xBi_(0.5)x)(Nb_(0.95-0.95x)Sb_(0.05-0.05x)Zrx)O_(3)ceramics were fabricated using conventional solid-state reaction.Then,the phase structures,dielectric,ferroelectric,and electricstrain properties were investigated.The compositions were tuned to be located at polymorphic phase boundary with increasing heterovalent Bi3t and Zr4t doping levels.A large strain of 0.19%was obtained at relatively low electric fields of 30 kV/cm in the composition of x=0.04.The normalized large-signal d33*values were approximately 633 pm/V under a low driving electric field of 30 kV/cm,which were comparable or larger than the values reported for other lead-free families.The large strains obtained can be attributed to the formation of nanodomains and high-density domain walls,which were confirmed by the observations of domain morphology using transmission electron microscopy(TEM)technique.Excellent temperature stability of the strain properties of the x=0.04 sample could be ascribed to the sluggish behaviour for the local structural heterogeneity in heterovalent-ion doped KNN ceramic.Theoretical simulations revealed that the Zr^(4t)produce the local stress at the BO6 octahedra and Bi3t could yield off-centering of AO12 ployhedron due to the nature of Bi 6s lone pair electrons,which induced lattice expansion and local distortions in the sample.The local displacements are strongly anisotropic in heterovalent-ion doped system.It is believed that random local fields exist in these compositions owing to the eixstence of charge distribution.Such heterovalent doping of Bi^(3t)and Zr^(4t)could destory simultaneously the orthorhombic symmetry and the short-range ferroelecctric order,leading to the formation of complex nanodomains and local structral hetergenenity.Heterovalent doping may,therefore,offer a new avenve to design novel K0.5Na0.5NbO3(KNN)-based materials for their mutifunctional applications.