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Accurate diagnosing of pneumonia and recognizing Anteroposterior and Posteroanterior in pediatric patients through chest X-ray (CXR) are critical components of contemporary computer-aided medical imaging systems. However, a prevalent issue in current methodologies is the suboptimal representation due to class imbalance, which is particularly pronounced in medical images, given the limited quantitative data for certain classes. Furthermore, despite the promising performance of deep learning models, they often face challenges when confronted with various manifestations of pediatric pneumonia and other lung diseases, aside from pneumonia itself. Thus, enhancing model generalization becomes imperative. To address these limitations, this paper presents a novel approach that combines weight adaptive contrast learning and knowledge governor distillation, namely SEACC. Firstly, we employ self-knowledge distillation, leveraging sample-level soft targets to enhance the model's generalization without incurring additional computational overhead. Secondly, we incorporate supervised contrastive learning, introducing innovative contrast weights among positive samples based on feature similarity. This technique promotes feature representations that exhibit intra-class compactness and inter-class dispersion. Experimental evaluations are conducted on a publicly Guangzhou Women and Children's Medical dataset, showing an improvement in Recall by ↑ 3. 3 % , in AUC by ↑ 10. 1 % , surpassing the existing SOTA methods. • Self-distillation boosts model generalization in variable medical image. • The synergy of contrastive learning and distillation boosts model performance comprehensively. • Adaptive weight contrastive learning can be used for precise pattern recognition. • Self-evolving and adaptive contrastive learning for classification model outperforms State-of-the-Art. [ABSTRACT FROM AUTHOR]

Integrating photovoltaics into windows provides the possibility of including an additional function of energy production to a conventional building fenestration component. There is no doubt that electrical power can be generated on-site. However, the effect of PV windows on the indoor luminous environment of the space served by them has not been comprehensively researched. This paper investigated the daylight performance of integrating four types of photovoltaics (semi-transparent thin film Cadmium telluride (CdTe) solar cells with 10% and 50% transparency, crystalline silicon solar cells with and without crossed compound parabolic concentrators (CCPC)) to a window of a typical south-facing office under different Window-to-Wall Ratios (WWRs). Annual useful daylight illuminance (UDI), daylight uniformity ratio (UR) and daylight glare probability (DGP) have been analysed based on dynamic simulation using RADIANCE. The simulation results show that windows integrated with crystalline silicon cells and CCPC optics have the potential to provide best daylight availability when compared with standard double glazed windows and other tested PV window prototypes, if it is applied to rooms with large WWRs (e.g. 60% or 75% WWR) at high latitudes (e.g. city of Harbin). Its application also improves the uniformity of daylight spatial distribution and eliminates the risk of glare. Semi-transparent CdTe PV window with 10% transparency can also improve the percentage of working hours that fall into UDI 500–2000lux range, however, it will result in the most sharp illuminance contrasts within the room. Applying all of these tested PV windows can effectively reduce the possibility of glare. • Window integrated PV provides daylight control in addition to energy generation. • Comprehensive daylight analysis was undertaken for four different PV windows. • Dynamic daylight metrics UDI, UR and DGP have been investigated using RADIANCE. • The effect of different WWRs on PV windows' daylight performance was explored. • PV windows can reduce the possibility of glare and maximise use the daylight. [ABSTRACT FROM AUTHOR]

Building-integrated semi-transparent photovoltaic windows (PV windows) have been considered as a potential candidate to replace conventional windows to improve building energy efficiency and hence reduce carbon emissions. With the integration of PV windows, the indoor luminous environment may be significantly affected. The presence of solar cells may cause undesirable shading, low illuminance levels and affect colour quality of the transmitted daylight. Therefore, it is important to comprehensively assess daylight performance of PV windows to ensure a comfortable luminous environment. In this study, the daylight performance of Cadmium telluride (CdTe) PV window with four different transparencies (i.e. 20%, 30%, 40% and 50%) applied to a cellular office space has been assessed in terms of daylight quantity and daylight quality. RADIANCE was selected to predict the annual daylight performance through advanced dynamic metrics including Useful Daylight Illuminance (UDI), simplified Daylight Glare Probability (DGPs) and Illuminance Uniformity (Uo). Correlated Colour Temperature (CCT) and Colour Rendering Index (CRI), which are two attributes to characterise the colour quality of transmitted daylight were used to evaluate performance of the selected PV windows. CCT and CRI were calculated under three CIE standard daylight scenarios (CCT of 4000 K, 6500 K and 25000 K respectively). It is found that CdTe PV windows can significantly improve the homogeneity of daylight distribution on a task area located close to the window and reduce the risk of daylight glare when compared with the performance of a conventional double glazing. Moreover, the recommended CCT (i.e. 3000–7500 K) can be achieved with the employment of CdTe PV windows under 4000 K and 6500 K daylight scenarios. All of the CdTe PV windows examined were able to maintain CRI at a comfortable level i.e. above 90 under the three daylight scenarios. • To evaluate the indoor luminous environment with semi-transparent CdTe window installed. • To assess the UDI, DGPs and U O using RADIANCE with CdTe windows installed. • To evaluate CCT and CRI influenced by CdTe windows using CIE standard. • The semi-transparent CdTe window offers good daylight quality and quantity. [ABSTRACT FROM AUTHOR]

Abstract New Ti-based bulk metallic glasses (BMGs) of Ti 32.8+X Zr 30.2−X Ni 5.3 Cu 9 Be 22.7 (3 ≤ |X| ≤ 15, at.%) with large size were prepared. The results reveal that the forming of primary icosahedral quasicrystal phase (I-phase) and the enthalpy of the primary crystallization (Δ H 1) were closely related to the glass forming abilities (GFAs). The crystallization product of the metallic glass alloys at primary crystallization state is a metastable I-phase. It is demonstrated that apparent activation energy for crystallization obtained by fitting the Kissinger equation at T x temperature increases with the increase of Ti concentration, while GFAs deteriorate. The Δ H 1 of metallic glasses declines with the increase of Ti concentration. The Ti 32.8+X Zr 30.2−X Ni 5.3 Cu 9 Be 22.7 possess high similar compressive fracture strength of about 1800 MPa, which is one of the best options as structural materials on account of high specific strength and low cost. [ABSTRACT FROM AUTHOR]

Highlights • A new Ti-based BMGC with the composition of Ti 57.3 Zr 19.6 Cu 4.7 Ni 2.8 Be 12 Nb 3.6 was developed. • The composite shows large homogeneous ductility and significant work-hardening capacity. • The toughening mechanism is a combined effect of stress-induced martensitic transformation and mechanical twinning. Abstract A new Ti-based BMGC with excellent tensile plasticity and significant work-hardening capacity was successfully developed. The microstructure, mechanical behaviors and toughening mechanisms were investigated in details by SEM, XRD, TEM and Nano-indentation. It is found that the stress-induced martensitic transformation from β to α″ phase and the mechanical twinning in the α″ phase combined to account for these mechanical behaviors. The current work offers a new perspective for developing in situ dendrite reinforced BMGCs with improved homogeneous ductility and significant work-hardening capacity. [ABSTRACT FROM AUTHOR]

Highlights • Switchable ETFE cushions has been employed in building envelope for daylight and solar heat control. • Ray-tracing techniques were used to investigate the effects of various design aspects of the ETFE. • A parametric study was carried out investigating the optical performance of switchable ETFE. • The impact of switchable ETFE cushions on building performance were studied. Abstract A pneumatic multilayer foil construction with a kinetic shading mechanism has the potential to be an effective response to dynamic climatic factors, such as solar radiation, and therefore moderate the energy consumption of buildings. A parametric study was carried out on a switchable ethylene-tetrafluoroethylene (ETFE) foil cushion with the purpose of investigating the optical performance of an adaptive building envelope and its impact on building energy performance regarding heating, cooling and lighting. Ray-tracing techniques were used to investigate the effects of surface curvature, frit layout and frit properties, on the optical performance of the cushion in open and closed mode. A range of incidence angles for solar radiation were simulated. The results of the simulation showed an angle dependent optical behaviour for both modes. The influence of the dynamic shading mechanism on building energy performance was further evaluated by integrating the optical data obtained for the ETFE foil cushions in a comprehensive energy simulation of a generic atrium building using EnergyPlus. Results suggested that switchable ETFE foil cushions have a higher potential to reduce cooling and heating loads in different climatic regions, compared to conventional glazing solutions (i.e. uncoated double-glazing and reflective double-glazing), while providing good conditions of natural daylighting. Annual energy savings of up to 44.9% were predicted for the switchable ETFE foil cushion in comparison to reflective double glazing. As such, this study provides additional insight into the optical behaviour of multilayer foil constructions and the factors of design and environment that potentially have a major impact on buildings energy performance. [ABSTRACT FROM AUTHOR]

This paper examines the international spillover effects of China's monetary policy shock on macro and financial variables in 26 countries along the Belt and Road (B&R) from 2000 to 2019. We find that a surprise Chinese monetary tightening brings about a widening in the short-term interest rate spread, a drop in the equity price, nominal depreciation against the RMB and real depreciation, and an improvement in the trade balance, on average, across the 26 B&R countries. Moreover, substantial heterogeneous effects emerge in the responses of the foreign real exchange rate and the trade balance in different groups in terms of the 26 countries' trade weights with China, capital openness, and national income levels. Finally, all the empirical evidence reveals that the expenditure switching effect plays an important role in facilitating the international transmission of China's monetary policy shock. • Estimates China's monetary policy shock series via a large Bayesian VAR model. • Examines the cross-border transmission of the shock via local projections. • Finds significant spillover effects of China' monetary policy shock abroad. • Finds heterogeneities in the spillover effects for different country groups. • Finds the expenditure switching effect is key in the monetary policy transmission. [ABSTRACT FROM AUTHOR]

Up to now, few work has concerned about the composition design strategy in the field of in-situ dendrite bulk metallic glass composites (BMGCs) for the difficulty to mediate single element in the multi-component system. In this work, an innovative composition design strategy was proposed, and a novel series of in-situ β dendrite reinforced Ti-based BMGCs were prepared. It was found that the real composition of the in-situ formed dendrites and amorphous phase is well consistent with the designed one. Accordingly, the dendrite composition is tailored monotonically and precisely, while the composition and volume fraction keep similar for the amorphous matrix in the composites. The microstructure of the dendrites and the mechanical properties and mechanisms of the overall composites are essentially controlled by the dendrite composition. According to the corresponding deformation mechanisms which transform from stress-induced martensitic transformation and mechanical twinning to dislocation slip, these alloys can be classified into two groups: the stress-induced martensitic transformation type and the none-phase transformation type. The composition design strategy proposed in this work and the correlation between the dendrite composition and the mechanical mechanisms may provide useful guidance for the development of in-situ β dendrite reinforced BMGCs with optimized mechanical properties. [ABSTRACT FROM AUTHOR]

A novel series of in - situ dendrite Ti-based bulk metallic glass composites (BMGCs) were obtained. The Mo content of the dendrites monotonically increases from nil to 10.5 at% while the dendrite volume fraction and the composition of the amorphous matrix remain nearly invariant. It was found that the mechanical behaviors varied tremendously simply by changing the Mo content. Thus, the correlation between the composition and the mechanical behaviors under tension has been determined for in - situ dendrite Ti-based BMGCs for the first time. [ABSTRACT FROM AUTHOR]

With the growing interest in providing internet access and cellular connectivity in the commercial aircraft, the compatibility between Air-to-Air (A2A) communications and current Air-to-Ground (A2G) macro-cellular communications is necessary to form an Aeronautical Ad hoc Network (AANet). Due to the typical features of airborne communications, such as high mobility, long transmission range and three-dimensional macro-cells, AANet is affected by intermittent links, which results in variant delayed data transmissions. To this end, we exploit a dynamic graph approach to model such an AANet with rapidly changing topology under a realistic airborne scenario. Targeting the problem of intermittent transmissions, by employing A2A, an AANet can bear three transmission modes: direct transmission, connected relay transmission and opportunistic transmission. To investigate the potential gain of A2A transmissions in terms of the end-to-end data flow transmission delay and the data traffic amount, we formulate an integer non-linear programming problem that minimizes the average end-to-end delay from Internet Gateways (IGWs) on shore to the aircraft receivers through multiple options of the transmission modes. Through solving this minimization problem based on the realistic dynamic graph model, the tradeoffs between the end-to-end transmission delay and other key network factors related to AANet formation and resource allocation can be obtained without much compromise on the transmission delay. The results show that the average end-to-end delay of the AANet is comparable to the direct transmission delay when having a tradeoff with the data traffic amount, buffer size and the spectrum sharing. [ABSTRACT FROM AUTHOR]

The Trombe wall (T-wall) has gained significant attention as an advanced building envelope capable effectively harvest solar energy. Improving the functionality and performance of the T-wall is critical for achieving energy-saving and positive energy buildings. This study focuses on enhancing the functionality and performance of the T-wall by incorporating with photovoltaic (PV) panels and aluminum panels in the T-wall chamber. Additionally, the PV panels and aluminum panels are laminated with photocatalyst and thermal materials to optimize their energy harvesting capabilities. In this photo/thermal catalytic Trombe wall system, the air within the wall system moves upwards due to thermal pressure and sweeps over the surface of the catalytic material when exposed to solar irradiation. Through the combined effects of solar energy and catalytic oxidation, the cold and dirty air in the chamber undergoes heating and purification processes, resulting in the desired heating effect while significantly improving the overall air quality within the environment. The experimental results highlight that the novel T-wall system offers a multifunctional solution that addresses electricity generation, heating, and improvement of indoor air quality. The main findings of this study are as follows: (1) During the period from 9:00 to16:00, the T-wall system demonstrates the ability to provide a range of 6.25 kJ/mol to 17.74 kJ/mol of heat and 0.075 kWh to 0.372 kWh of electricity per day. (2) In terms of indoor air quality improvement, the T-wall system exhibits a one-way sterilization efficiency of bacterial aerosols ranging from 0.204 to 0.347. (3) The comprehensive performance of the system was found to be optimal when the system spacing is 25 cm. (4) In terms of the layout of UV light, it was observed that at the top and bottom of the system yielded better sterilization efficiency. [ABSTRACT FROM AUTHOR]

Lightweight materials with good combinations of properties, such as high strength, ductility and damage tolerance, are highly desirable in engineering applications; nevertheless, it remains a challenge to "defeat" the generally exclusive relationships between different properties for structural materials. One viable means is to construct complicated architectures in materials. Here, we employ a lightweight Ti-based metallic glass (MG) and pure Ti as constituents and assemble them into a hierarchically-structured multiphase composite with tailored heterogeneity. The Ti-rich multiphase composite exhibits a relatively low density of 4.95 g ∙ c m − 3 owing to its high Ti content and a high strength of ∼1408 MPa derived primarily from the MG phase. The hierarchical architecture with tailored heterogeneity promotes the formation of abundant shear bands and microcracks in MG, yet inhibits their extension to avoid catastrophic fracture, thereby endowing the Ti-rich multiphase composite with a remarkable tensile ductility of ∼7.1% which is nearly two times that of the MG composite having similar phase constitution but a uniform structure. Moreover, this architecture causes crack-tip blunting by promoting plastic deformation, together with crack bifurcation and microcracking ahead of the crack tip, which bestows a high (notched) fracture toughness of ∼109 M P a ∙ m 1 / 2 which is around three times that of its counterpart. This study is intended to give insight for the architectural design of new materials by offering a viable means for their architectural construction to achieve good combinations of properties. [ABSTRACT FROM AUTHOR]

Impact deformed TiAl polysynthetic twinned crystal was investigated by scanning and transmission electron microscopy including aberration-corrected scanning transmission electron microscopy. Shear bands, deformation twins and dislocations were observed in γ-TiAl phase. Deformation twins were identified on both primary (11 1 ¯ ) and secondary (1 1 ¯ 1 ¯ ) twin planes, and dislocation structures were resolved on the coherent {111} twin boundaries. Among them, 1/6 < 211] pseudo-twin dislocations were observed on the coherent twin boundaries co-existing with 1/2 < 101] super-partial dislocations. Two types of shear bands were identified, one was composed of (11 1 ¯ ) twin lamellae inclined to the propagation direction of shear bands, while the other was composed of curved (1 1 ¯ 1 ¯ ) twin lamellae and its propagation is nearly parallel to the (1 1 ¯ 1 ¯ ) twin plane. [ABSTRACT FROM AUTHOR]

With respect to deep narrow groove structures with high length-width ratio and high depth-width ratio (particularly when the ratio is greater than 10), the cathode rigidity and flow-field stability deteriorate during the electrochemical machining (ECM) process. To improve the machining efficiency and process stability of deep narrow grooves with high length-width ratio, a hollow slice cathode with stiffeners was designed and optimized to meet the rigid requirements using the method of one-way fluid-solid coupling finite element analysis. Additionally, the effects of cathode stiffener size, stiffener distribution, and cathode vibrating feed mode on the flow field in the machining gap were investigated using the flow-field simulation analysis method. The simulation results indicate that cavitation and electrolyte starvation in the machining gap are avoided with a reasonable stiffener design, and the renewal of electrolyte in the machining gap is improved with a reasonable vibration motion. Contrast experiments were performed based on the simulation results. The experimental results verified that the optimal design of stiffeners and the reasonable cathode vibration improve the stability of the flow field. Moreover, process stability and machining efficiency of ECM of deep narrow grooves with high length-width ratio improve with the adoption of the optimal vibrating feed parameters. [ABSTRACT FROM AUTHOR]

A new method was proposed to pinpoint the compositions with good glass forming ability (GFA) by combining atomic clusters and mixing entropy. The clusters were confirmed by analyzing competing crystalline phases. The method was applied to the Zr–Al–Ni–Cu–Ag alloy system. A series of glass formers with diameter up to 20 mm were quickly detected in this system. The good glass formers were located only after trying 5 compositions around the calculated composition. The method was also effective in other multi-component systems. This method might provide a new way to understand glass formation and to quickly pinpoint compositions with high GFA. [ABSTRACT FROM AUTHOR]