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The presence of defects at the interface between the perovskite film and the carrier transport layer poses significant challenges to the performance and stability of perovskite solar cells (PSCs). Addressing this issue, we introduce a dual host-guest (DHG) complexation strategy to modulate both the bulk and interfacial properties of FAPbI3-rich PSCs. Through NMR spectroscopy, a synergistic effect of the dual treatment is observed. Additionally, electro-optical characterizations demonstrate that the DHG strategy not only passivates defects but also enhances carrier extraction and transport. Remarkably, employing the DHG strategy yields PSCs with power conversion efficiencies (PCE) of 25.89% (certified at 25.53%). Furthermore, these DHG-modified PSCs exhibit enhanced operational stability, retaining over 96.6% of their initial PCE of 25.55% after 1050 hours of continuous operation under one-sun illumination, which was the highest initial value in the recently reported articles. This work establishes a promising pathway for stabilizing high-efficiency perovskite photovoltaics through supramolecular engineering, marking a significant advancement in the field. The defects at the perovskite/carrier transport layer interface pose significant challenges to the performance of perovskite solar cells. Here, the authors introduce a dual host-guest complexation strategy with Cs-crown-ether and ammonium salt, achieving a high PCE of 25.9% with superior stability. [ABSTRACT FROM AUTHOR]

We present the first application of the mixed-frequency VAR (MF-VAR) method in the market microstructure literature, studying the interaction between stock market returns and foreign investors' trading. MF-VAR allows us to use daily investor trading data together with higher-frequency return series and uncover novel intraday patterns in the feedback trading behavior and the information content of trading. Using data from Korea, we find that foreign investors chase opening-hour returns, and their trading has the ability to forecast subsequent days' late-hour returns. This pattern suggests that foreign investors selectively respond to the information incorporated during opening hours. Over the years, foreign investors' response to intraday returns has become more prompt, and the predictive ability of their trading has disappeared. A specific test made feasible by the MF-VAR method does not support the global private information hypothesis. [ABSTRACT FROM AUTHOR]

Nowadays, the information obtainable from the markets are potentially limitless. Economic theory has always supported the possible advantage obtainable from having more information than competitors, however quantifying the advantage that these can give has always been a problem. In particular, in this paper we study the amount of information obtainable from the markets taking into account only the time series of the prices, through the use of a specific Generative Adversarial Network. We consider two types of financial instruments traded on the market, stocks and cryptocurrencies: the first are traded in a market subject to opening and closing hours, whereas cryptocurrencies are traded in a 24/7 market. Our goal is to use this GAN to be able to "convert" the amount of information that the different instruments can have in discriminative and predictive power, useful to improve forecast. Finally, we demonstrate that by using the initial dataset with the 5 most important feature useds by traders, the prices of cryptocurrencies present higher discriminatory and predictive power than stocks, while by adding a feature the situation can be completely reversed. [ABSTRACT FROM AUTHOR]

Device life time is a significant consideration in the cost of ownership of quantum cascade lasers (QCLs). The life time of QCLs beyond an initial burn-in period has been studied previously; however, little attention has been given to predicting premature device failure where the device fails within several hundred hours of operation. Here, we demonstrate how standard electrical and optical device measurements obtained during an accelerated burn-in process can be used in a simple support vector machine to predict premature failure with high confidence. For every QCL that fails, at least one of the measurements is classified as belonging to a device that will fail prematurely—as much as 200 h before the actual failure of the device. Furthermore, for devices that are operational at the end of the burn-in process, the algorithm correctly classifies all the measurements. This work will influence future device analysis and could lead to insights on the physical mechanisms of premature failure in QCLs. [ABSTRACT FROM AUTHOR]

The level of operational effectiveness (LOE) is a color-coded performance metric that is monitored by the cybersecurity operations center (CSOC). It is determined using the average time to analyze alerts (AvgTTA) in every hour of shift operation, where the time to analyze an alert (TTA) is the sum of waiting time in the queue and investigation time by the analysts. Ideally, the CSOC managers would set a predetermined baseline target for AvgTTA to be maintained for every hour of shift operation. However, due to adverse events, an imbalance may exist if the alert arrival rate far exceeds the service rate, resulting in high AvgTTA or low LOE. Upon exhausting all the analyst resources, the only option available to a CSOC manager is to discard alerts for restoring the LOE of the CSOC. The paper proposes two strategies: the value-based strategy is developed using a static optimization model while the reinforcement learning-based strategy is developed using a dynamic optimization model. The paper compares various strategies for discarding alerts and measures the following desiderata for comparing them: (1) minimize the number of alerts discarded, (2) ensure highest utilization of analysts, (3) determine the optimal time at which the alerts must be discarded in a shift, and (4) maintain the best possible LOE closest to the baseline target LOE. Results indicate that, overall, the RL strategy is the best performer among all strategies that guarantees the AvgTTA below the threshold value in every hour of shift operation while discarding the fewest number of alerts under adverse events. [ABSTRACT FROM AUTHOR]

The insulation materials are used to reduce heat loss to/from the ducts with additional investment. This study introduces an air gap between insulation and duct surface to reduce the quantity of insulation. It uses lifecycle cost (LCC) analysis to determine the economic benefits of the air gap, considering four insulation materials for insulating the duct and natural gas as an energy source for chiller operation. The preliminary data regarding design and operating parameters were obtained from a renowned pharmaceutical company. The duct's annual energy loss was estimated for given operation hours in a year using the preliminary data and ambient conditions. The estimated energy loss through the duct was fed in LCC analysis to determine the impact of the air gap on optimum insulation thickness (OIT) corresponding to the minimum LCC and payback period. Results revealed that OIT thickness for a duct with an air gap was lower than insulated duct without an air gap, resulting in maximum cost savings within a shorter payback period. Among different insulation materials, insulated duct with expanded polystyrene was investigated as cost-effective insulation material with maximum cost savings of USD (508.8–766.8)/m/year and a payback period of 1.15–1.17 years. On the contrary, the air gap was the most effective in terms of cost savings for the ducts insulated with rock wool. In conclusion, an air gap is a cost-effective design approach for duct applications. [ABSTRACT FROM AUTHOR]

We investigate how the economic consequences of the pandemic and the government-mandated measures to contain its spread affect the self-employed — particularly women — in Germany. For our analysis, we use representative, real-time survey data in which respondents were asked about their situation during the COVID-19 pandemic. Our findings indicate that among the self-employed, who generally face a higher likelihood of income losses due to COVID-19 than employees, women are about one-third more likely to experience income losses than their male counterparts. We do not find a comparable gender gap among employees. Our results further suggest that the gender gap among the self-employed is largely explained by the fact that women disproportionately work in industries that are more severely affected by the COVID-19 pandemic. Our analysis of potential mechanisms reveals that women are significantly more likely to be impacted by government-imposed restrictions, e.g., the regulation of opening hours. We conclude that future policy measures intending to mitigate the consequences of such shocks should account for this considerable variation in economic hardship. [ABSTRACT FROM AUTHOR]

Background: Advanced cancer therapeutics have improved patient survival, leading to an increase in the number of patients who require long-term outpatient chemotherapy. However, the available schedule options for chemotherapy are generally limited to traditional business hours. Method: In 2017, we surveyed 721 patients with cancer in Okayama, Japan, regarding their preferences for evening and weekend (Friday evening, Saturday, and Sunday) chemotherapy appointments. Results: A preference for evening and weekend appointment options was indicated by 37% of the respondents. Patients who requested weekend chemotherapy were younger, female, with no spouse or partner, living alone, employed, and currently receiving treatment. Among these factors, age and employment status were significantly associated with a preference for weekend chemotherapy, according to multivariate analysis. Conclusion: Our findings reveal a demand for evening and weekend outpatient chemotherapy, especially among young, employed patients. [ABSTRACT FROM AUTHOR]

In this paper, we address the multiple operating room (OR) surgical case sequencing problem (SCSP). The objective is to maximise total OR utilisation during standard opening hours. This work uses a case study of a large Australian public hospital with long surgical waiting lists and high levels of non-elective demand. Due to the complexity of the SCSP and the size of the instances considered herein, heuristic techniques are required to solve the problem. We present constructive heuristics based on both a modified block scheduling policy and an open scheduling policy. A number of real-time reactive strategies are presented that can be used to maintain schedule feasibility in the case of disruptions. Results of computational experiments show that this approach maintains schedule feasibility in real-time, whilst increasing operating theatre (OT) utilisation and throughput, and reducing the waiting time of non-elective patients. The framework presented here is applicable to the real-life scheduling of OT departments, and we provide recommendations regarding implementation of the approach. [ABSTRACT FROM AUTHOR]

Photovoltaic thermoelectric air-conditioning system (PT A/C) system could be a greater option compared to conventional A/C system as it is Freon-free and absence of moving parts. This study investigated the cooling and dehumidification performance of a PT A/C that is solely powered by solar energy under tropical climate conditions. The system is built with 9 pieces of thermoelectric to provide cooling for a test chamber of 3.6 m3 volume. The effect of input current on the system's cooling and moisture removal rate were investigated and results showed that 5 A is the optimum current level, providing an average of 181 W cooling capacity and 0.14 ltr/hour of moisture removal rate at the given ambient conditions. During the operation, indoor temperature of the test chamber was 4 °C lower than the unconditioned chamber and 7.7 °C compared to the ambient temperature. Whereas the indoor relative humidity varies between 58~83 %. Furthermore, for a 12 hours operation, the system consumes 1.45 kWh of energy, and delivered temperature between 23.8 to 27.8 ºC at 5 A. [ABSTRACT FROM AUTHOR]

Aldi, the biggest discounter in Germany, started to systematically extend shopping hours of its stores in 2016. We interpret the decision to extend opening hours of a specific Aldi store as entry into a new market. By using a novel data set containing the opening hours of nearly all German grocery retailers, we find the following interesting correlations: The probability that a given Aldi outlet extends its shopping hours past 8 p.m. (i) increases if nearby Aldi outlets already extended shopping hours and (ii) decreases if nearby stores run by Aldi's close competitors did not expand shopping hours past 8 p.m.. These results seem surprising in conjunction with cannibalization and residual demand, but can be explained by consumer and firm learning or market expansion. [ABSTRACT FROM AUTHOR]

The paper presents an interactive electronic guide application prototype able to recommend personalized multiple-day tourist itineraries to mobile web users. The proposed application relies on an evolutionary optimizer that allows the determination, in an acceptable time, of a near-optimal user-adapted tour for each day of the visit by considering different conflicting objectives. The tour optimizer automatically plans the itinerary by selecting the sights of potential interest based on user preferences, the available visit time considered on a daily basis, opening days and hours, visiting times, accessibility of the places of interest and weather forecasting. The interactive functionalities and facilities provided by the application are illustrated along with the model used to adapt the tourist itinerary to user preferences and constraints. An experimental qualitative and quantitative evaluation has been performed to assess the validity of the guide prototype. Particular attention has been devoted to the usability of the application and its graphic unit interface along with user satisfaction. [ABSTRACT FROM AUTHOR]

This paper examines retail strategies related to business hours, store quality, and price. We consider a cost regime in which quality investments are more costly for extended business hours. The cost regime captures additional investment costs for customer and security service during late hours. This is a novel feature in the existing literature on retail competition in business hours and prices. We show that a retailer with shorter business hours chooses higher store quality and charges lower prices. We also find that the liberalization of business hours is desirable in view of social welfare because store quality and demand under liberalized business hours are greater than those under regulated business hours. [ABSTRACT FROM AUTHOR]

This study reports the first radon concentration measurements within three frequently visited caves in Florida: one touristic (Florida Caverns), one private (Ocala Caverns), and one private, but publicly accessible (Jennings Cave). To measure the radon concentration, 18 CR-39 solid-state alpha track detectors were placed along the main passages of these caves for a period of 2 months (between December 2016 and February 2017). The results show that the radon concentration throughout all caves greatly exceeds the recommended safety action level. The highest concentrations of 2737 and 2958 Bq m−3 were recorded in Ocala and Jennings caves, respectively; whereas in Florida Caverns, the concentration reached a value as high as 1050 Bq m−3. To aid in ventilation, allowing the built-up gas to disperse, it is suggested that at Florida Caverns, the entry doors to be periodically opened for several hours. In locations with high concentrations where additional ventilation is not possible, such as Ocala and Jennings, it is recommended that the exposure time to be limited. Although radon values measured in the surveyed caves are high, the occasional cave visits are generally safe as the overall exposure time is minimal. However, cave guides and workers may have an increased risk as they spend many hours a day during which they are exposed to these high radon concentrations. [ABSTRACT FROM AUTHOR]