Daily Performance Research Articles

Evaluation of Daily and Hourly Performance of Multi-Source Satellite Precipitation Products in China’s Nine Water Resource Regions

Satellite precipitation products (SPPs) are of great significance for water resource management and utilization in China; however, they suffer from considerable uncertainty. While numerous researchers have evaluated the accuracy of various SPPs, further investigation is needed to assess their performance across China’s nine major water resource regions. This study used the latest precipitation dataset of the China Meteorological Administration’s Land Surface Data Assimilation System (CLDAS-V2.0) as the benchmark and evaluated the performance of six SPPs—GSMaP, PERSIANN, CMORPH, CHIRPS, GPM IMERG, and TRMM—using six indices: correlation coefficient (CC), root mean square error (RMSE), mean absolute error (MAE), probability of detection (POD), false alarm rate (FAR), and critical success index (CSI), at both daily and hourly scales across China’s nine water resource regions. The conclusions of this study are as follows: (1) The performance of the six SPPs was generally weaker in the west than in the east, with the Continental Basin (CB) exhibiting the poorest performance, followed by the Southwest Basin (SB). (2) At the hourly scale, the performance of the six SPPs was weaker compared to the daily scale, particularly in the high-altitude CB and the high-latitude Songhua and Liaohe River Basin (SLRB), where observing light precipitation and snowfall presents significant challenges. (3) GSMaP, CMORPH, and GPM IMERG demonstrated superior overall performance compared to CHIRPS, PERISANN, and TRMM. (4) CMORPH was found to be better suited for application in drought-prone areas, showcasing optimal performance in the CB and SB. GSMaP excelled in humid regions, displaying the best overall performance in the remaining seven basins. GPM IMERG serves as a complementary precipitation data source for the first two.

Influence of the demand side management on the daily performance of microgrids in smart environments using grey wolf optimizer

PurposeThis study aims to investigate the daily performance of the proposed microgrid (MG) that comprises photovoltaic, wind turbines and is connected to the main grid. The load demand is a residential area that includes 20 houses.Design/methodology/approachThe daily operational strategy of the proposed MG allows to vend and procure utterly between the main grid and MG. The smart metre of every consumer provides the supplier with the daily consumption pattern which is amended by demand side management (DSM). The daily operational cost (DOC) CO2 emission and other measures are utilized to evaluate the system performance. A grey wolf optimizer was employed to minimize DOC including the cost of procuring energy from the main grid, the emission cost and the revenue of sold energy to the main grid.FindingsThe obtained results of winter and summer days revealed that DSM significantly improved the system performance from the economic and environmental perspectives. With DSM, DOC on winter day was −26.93 ($/kWh) and on summer day, DOC was 10.59 ($/kWh). While without considering DSM, DOC on winter day was −25.42 ($/kWh) and on summer day DOC was 14.95 ($/kWh).Originality/valueAs opposed to previous research that predominantly addressed the long-term operation, the value of the proposed research is to investigate the short-term operation (24-hour) of MG that copes with vital contingencies associated with selling and procuring energy with the main grid considering the environmental cost. Outstandingly, the proposed research engaged the consumers by smart meters to apply demand-sideDSM, while the previous studies largely focused on supply side management.

Can leaders motivate employees’ energy-efficient behavior with thoughtful communication?

We study the effect of an employer’s communication concerning energy-efficient behavior on a firm’s employees’ behavioral responses. The management aims to enhance energy-efficient behavior performance by irregularly sending online messages to remote employees. We break down each message, analyzing the positive or negative emotions conveyed, collective or individual orientation, and ease of language. Comparing employees’ daily energy efficiency after receiving a message to their daily performance without a previous message, we find that messages generally result in an immediate increase in efficiency. Messages conveying negative emotions and those making a distinction between the manager and the employees have a smaller effect than messages conveying positive emotions and emphasizing a collective orientation that includes both the management and employees. Additionally, shorter messages are more likely to induce improved efficiency. Sending messages significantly impacts driver performance for up to six days after the message, resulting in economically relevant cost reductions.

Supporting Functional Goals in Spinal Muscular Atrophy: A Case Report of The Cognitive Orientation to Daily Occupational Performance (CO-OP) Approach

Supporting Functional Goals in Spinal Muscular Atrophy: A Case Report of The Cognitive Orientation to Daily Occupational Performance (CO-OP) Approach

Their bad experiences make me think twice: Customer‐to‐colleague incivility, self‐reflection, and improved service delivery

AbstractPrior research has shown that customer incivility impacts targeted employees' performance. Yet, whether such experiences also influence bystander employees has been overlooked. In this work, we take a third‐party perspective and suggest that observed customer‐to‐colleague incivility may have a positive impact on bystander employees' service performance. Drawing on social learning theory, we develop a model where we study the consequence of observed customer‐to‐colleague incivility on service performance through self‐reflection. A two‐week experience sampling study with data collected from 99 nurses revealed that, observed daily customer‐to‐colleague incivility was positively related to bystander employees' daily self‐reflection, which in turn was positively associated with their daily service performance. Moreover, we identified performance‐based self‐esteem (i.e., the importance of performance to self‐esteem) as a key boundary condition that explains for whom witnessing customer‐to‐colleague incivility is more likely to engender higher self‐reflection. The theoretical and practical implications of these findings are discussed.

Application Research and Teaching Implementation of Rubik's Cube Furniture in Home Design

A diversified teaching evaluation system has been established based on the characteristics of teaching content, with more diverse evaluation subjects including enterprises, teachers, and students. The evaluation content is more diverse, including daily performance evaluation, homework evaluation, project implementation evaluation, and project achievement evaluation; The evaluation methods are more diverse, including enterprise evaluation, teacher evaluation, teacher-student mutual evaluation, questionnaire voting, and other evaluation methods.

Differences in Daily Activity Performance Between Inpatient Rehabilitation Facility and Home Among Stroke Survivors.

Stroke survivors are one of the largest consumer groups of rehabilitation services. Despite improvement in daily activities while in inpatient rehabilitation, many have difficulty performing daily activities at home after discharge. The difference in performance between a standard clinical context and at home is poorly understood. To better understand differences in activity performance during transition from inpatient rehabilitation facility (IRF) to home, we examined daily activity performance scores from 2 different environments (IRF and home) at the same time point (discharge). This was a cross-sectional analysis using baseline data from a randomized controlled trial. Participants were stroke survivors aged ≥50 who planned to discharge home from the IRF. The Functional Independence Measure and Section GG codes (both converted to International Classification of Functioning, Disability, and Health scores) were conducted per protocol first at home and then in the IRF at discharge (≤3 days apart, order not randomized). Among 57 participants, activity scores at home were significantly worse than scores at IRF discharge. Over 40% of participants had discharge scores indicating no-to-mild impairment for shower/tub transfer, walking, and going up/down stairs, while home visit scores indicated moderate-to-complete impairment for those activities. The greatest differences in scores were for shower/tub transfer (median difference 1.5, 95% CI 1.00-2.00) and going up/down stairs (median difference 1.50, 95% CI 1.00-2.00). The environment plays an important role in stroke survivors' functioning at home. Future studies should further examine how the environment impacts activity performance upon returning home following stroke.

Application of Neural Rehabilitation Manipulator Training in Upper Limb Rehabilitation of Stroke Patients with Hemiplegia

Objective: To analyze the application of neural rehabilitation manipulator training in upper limb rehabilitation of stroke patients with hemiplegia. Methods: 94 patients with hemiplegia after stroke were selected from January 2021 to January 2023. The patients were randomly divided into a control group and an observation group, with 47 cases in each group. The control group received routine rehabilitation training while the observation group received neural rehabilitation manipulator training. The upper limb and nerve function, daily task performance ability, quality of life, and rehabilitation training satisfaction were compared between the two groups. Results: There was no significant difference in upper limb and nerve function between the two groups before training, P > 0.05. After training, the observation group had 51.45 ± 8.75 points in ARAT and 52.59 ± 8.48 points in FMA-UE, which were higher than those in the control group with 43.81 ± 6.67 points and 45.51 ± 7.31 points respectively, P < 0.05. The observation group had 5.71 ± 1.53 points in NIHSS, which was lower than those in the control group with 8.04 ± 2.39 points, P < 0.05. In terms of daily task performance ability and quality of life, there was no significant difference between the two groups before training, P > 0.05. After training, the observation group had 78.54 ± 10.63 scores in MBI and 171.93 ± 19.12 scores in SS-QOL, which were higher than those in the control group with 70.51 ± 9.25 scores and 160.13 ± 18.42 scores respectively, P < 0.05. In terms of satisfaction, the total satisfaction rate of the observation group was 93.62%, which was higher than that of the control group with 74.47%, P < 0.05. Conclusion: The application of neural rehabilitation manipulator training in the upper limb rehabilitation of stroke patients with hemiplegia can significantly improve the upper limb function of patients, relieve nerve defects, improve daily task performance ability and quality of life, and increase patient satisfaction with rehabilitation training.

The association between objective and subjective oral health conditions and the presence of anorexia of aging among Japanese older Adults1

Anorexia of aging is a risk factor for malnutrition among older adults. This study aimed to evaluate the association between objective and subjective oral health and anorexia among independent older adults. This cross-sectional study targeted independent older adults aged ≥65 years who participated in the Japan Gerontological Evaluation Study conducted in 2022. The outcome variable was the presence of anorexia, as assessed by the Simplified Nutritional Appetite Questionnaire. Exposure variables were dental status (≥20 teeth, 10–19 teeth with/without dentures, and 0–9 teeth with/without dentures) as objective oral health and oral health-related quality of life measured by five items of the short version of the Oral Impacts on Daily Performances (OIDP) (eating, speaking, smiling, emotional stability, and enjoying with others) as subjective oral health. We fitted the Poisson regression model, including possible confounders, and estimated prevalence ratios (PRs) and 95% confidence intervals. Among 19,787 participants (mean age: 74.6 years [1SD = 6.2], male: 48.5%), 9.0% were classified as having anorexia. After adjusting possible confounders, those with ≤19 teeth had a higher proportion of experiencing anorexia compared to those with ≥20 teeth; however, the association was less pronounced among those with dentures (0−9 teeth with dentures: PR = 1.48 [1.31−1.68], and 0−9 teeth without dentures: PR = 2.08 [1.65−2.63]). Even after adjusting for dental status, each item of OIDP was significantly associated with the presence of anorexia (all p < 0.05). The results showed that both objective and subjective poor oral health were significantly associated with a higher probability of developing anorexia of aging. Therefore, improving both objective and subjective oral health through appropriate dental care could contribute to maintaining appetite in later life.

Factors associated with foreign-educated nurses’ willingness to continue working in Japan: a qualitative study

BackgroundJapan has been accepting foreign nurse candidates since 2008 under Economic Partnership Agreements (EPAs). As globalisation progresses, nurses from diverse backgrounds are expected to play an active role in the medical field. Using an interview survey, this study examined the factors associated with EPA nurses’ willingness to continue working in Japan.MethodsWe conducted semi-structured interviews from January 2022 to July 2023 with eight EPA nurses and one EPA nurse candidate working in Japan to investigate the factors associated with foreign-educated nurses’ willingness to continue working in Japan. The interview guide included items on the status of the daily performance of their duties, what they found pleasurable in their nursing experience in Japan, difficulties they encountered in carrying out their nursing duties, and their expectations of the Japanese staff around them. Data were analysed using thematic analysis.ResultsFrom the interview data, seven themes were extracted. To continue working in Japan, it was important for EPA nurses to be able to communicate with patients and colleagues, maintain self-esteem and motivation, be resilient, have support from EPA peers and family members, be accepted by others such as patients and colleagues, and be satisfied with the support they received.ConclusionThe EPA nurses experienced many difficulties after becoming nurses and tended to be isolated because of their non-Japanese status. The results suggest that not only support from colleagues and supervisors but also a general understanding of EPA nurses from Japanese society is necessary. As globalisation accelerates, the Japanese nursing field needs to understand the diversity of the nursing profession and build a support system that will enable them to continue to take pride and feel motivated in their work.

Evaluation of Electromagnetic Therapy in the Treatment of Severe Dysmenorrhea in Young Women of Basrah.

Primary dysmenorrhea (PD) is a public disease of young female worldwide, it affects their daily performances. Severe recurrent uterine cramps are the main complaints in 90% of adolescents and 50% of reproductive-age females. This study aimed to evaluate the use of magnetic field therapy in the treatment of severe dysmenorrhea grade 3 and provide an encouraging goal to continue daily work without pain. Two hundred and fifty female patients were recruited in this study from gynecological clinics in Basrah, southern Iraq. All had severe dysmenorrhea, patients were subjected to a questionnaire form, Visual Analog Scale, and verbal multidimensional scoring system to determine the pain intensity and grade of dysmenorrhea. Only 38 young females had severe dysmenorrhea grade 3 with ages ranging from 16 to 28 years with a mean age of 22.04 ± 1.43 years and body mass index 23.81 ± 1.94, patients subjected to electromagnetic field therapy (EMFT), two sessions per week for 20 min each for 6 weeks. Three categories were assessed, working ability, associated symptoms, and drugs used. Data were collected and statistically analyzed using SPSS version 22. The present study showed statistically significant progress (P < 0.05) in reducing pain, rare physical and mental complaints, and improved working ability with no need for drugs in majority of patients. EMFT has better results than other methods in relieving pain and symptoms of dysmenorrhea with a settled lifestyle.

Novel definition of textbook outcome in biliary system cancers and its influence on patients' survival and quality of life.

The definition of textbook outcome in biliary system cancers is a developing concept in need of expansion and investigation of its association with survival and quality of life. In this original research, we developed a novel "all or none" textbook outcome definition which addresses the rapid recovery of post-surgical indexes, in addition to short-term mortality, hospital re-admission, prolonged stay, surgical margin and postoperative complications. Based on the fulfillment of relevant criteria, patients were divided into textbook outcome and non-textbook outcome groups and their characteristics and survival data were analyzed. A customized "quality of life" questionnaire was developed to address short-term recovery and post-discharge life quality of patients. Association with quality of life improvement was then investigated. A total of 129 patients were included. Textbook outcome was achieved in 25.58% of patients (37.04% of gallbladder cancer patients and 17.8% of cholangiocarcinoma patients). Compared to non-textbook outcome group, patients with textbook outcome had lower rate of pre-operative biliary drainage (p = 0.026), higher rate of normal preoperative liver function (p < 0.001) and tumor markers (p = 0.001), reduced perioperative bleeding (p = 0.006) and blood transfusion (p = 0.005), and higher rate of N0 stage cases (p = 0.008). Textbook outcome was also associated with enhanced survival, significantly in older patients (<65 years) (1-year survival rate: 100% vs. 78.57% (p = 0.108), 2-year survival rate: 87.5% vs. 44% (p = 0.046)). Finally, textbook outcome was significantly associated with enhanced basic daily performance (p < 0.001), social life performance (p = 0.033), and personal evaluation (p < 0.001), and thus improved quality of life (p < 0.001). The novel definition of textbook outcome was able to address the specific nature of recovery after resection of biliary system cancers. Expanding the scope of textbook outcome and addressing the influence on survival and quality of life provides a comprehensive concept able to reflect physical, psychological and functioning enhancements in patients recovery.

Effect of Cognitive Orientation to Daily Occupational Performance (CO-OP) Programme on Playfulness in Children with Attention Deficit Hyperactivity Disorder

Objective: To investigate the effect of cognitive orientation to daily occupational performance (CO-OP) programme on playfulness in children with attention deficit hyperactivity disorder.Material and Methods: Seventy Attention deficit hyperactivity disorder participants (N=70), aged between 6-8 years were recruited from a local community-based setting. The children were divided into an experimental (n=35) and a control group (n=35). The experimental group participants received CO-OP and the control group participants received the conventional occupational therapy programme; for 12 weeks. The test on playfulness was used to measure playfulness in children.Results: There were statistically significant differences between pretest and post-test scores of the test of playfulness (TOP) in the experimental group (p-value≤0.05) components of: Extent, Intensity and Skillfulness, and there were statistically significant differences between pretest and post-test group of TOP in the control group (p-value≤0.05) in Intensity and Skillfulness. There was no statistically significant difference in pretest and post-test scores of TOP in the component of Extent. Further analysis revealed that clinically there was significant differences in the post-test scores of TOP between the control and experimental group components of Extent, Intensity and Skillfulness.Conclusion: CO-OP was effective in improving playfulness in children with attention deficit hyperactivity disorder.

Evaluating the Impact of Learning Management Systems in Geographical Education in Primary School: An Experimental Study on the Importance of Learning Analytics-Based Feedback

Traditionally, educational processes were focused on learning theoretical geography content, often supplemented with hands-on activities. However, advances in technology have enabled the integration of Learning Management Systems (LMSs) such as Moodle, which enable students to learn at their own pace, receive instant and individualized feedback about their daily academic performance, and gather more daily information individually based on techniques such as Learning Analytics (LAs). Despite these benefits, there is a lack of evidence supporting this educational approach in primary education. This experimental study, involving 80 fifth-grade students, aims to address this gap while investigating the territorial and socio-economic organization of their environment and comparing two types of feedback provided: simply the correct answer (control group), and more extensive (experimental group). The findings suggest that the implementation of Moodle tasks facilitates learning, irrespective of the type of feedback provided. However, students rated activities higher in terms of usefulness and satisfaction with the teaching–learning process when extensive feedback was provided. Additionally, the daily data collected proved useful for teachers in predicting students’ final outcomes. These results highlight the potential benefits of carrying out activities in Moodle, despite their short duration, particularly at this academic level and within this knowledge domain.

A usability study on mobile EMG-guided wrist extension training in subacute stroke patients-MyoGuide

BackgroundEffective stroke rehabilitation requires high-dose, repetitive-task training, especially during the early recovery phase. However, the usability of upper-limb rehabilitation technology in acute and subacute stroke survivors remains relatively unexplored. In this study, we introduce subacute stroke survivors to MyoGuide, a mobile training platform that employs surface electromyography (sEMG)-guided neurofeedback training that specifically targets wrist extension. Notably, the study emphasizes evaluating the platform’s usability within clinical contexts.MethodsSeven subacute post-stroke patients (1 female, mean age 53.7 years, mean time post-stroke 58.9 days, mean duration per training session 48.9 min) and three therapists (one for eligibility screening, two for conducting training) participated in the study. Participants underwent ten days of supervised one-on-one wrist extension training with MyoGuide, which encompassed calibration, stability assessment, and dynamic tasks. All training records including the Level of Difficulty (LoD) and Stability Assessment Scores were recorded within the application. Usability was assessed through the System Usability Scale (SUS) and participants’ willingness to continue home-based training was gauged through a self-developed survey post-training. Therapists also documented the daily performance of participants and the extent of support required.ResultsThe usability analysis yielded positive results, with a median SUS score of 82.5. Compared to the first session, participants significantly improved their performance at the final session as indicated by both the Stability Assessment Scores (p = 0.010, mean = 229.43, CI = [25.74–433.11]) and the LoD (p < 0.001; mean: 45.43, CI: [25.56–65.29]). The rate of progression differed based on the initial impairment levels of the patient. After training, participants expressed a keen interest in continuing home-based training. However, they also acknowledged challenges related to independently using the Myo armband and software.ConclusionsThis study introduces the MyoGuide training platform and demonstrates its usability in a clinical setting for stroke rehabilitation, with the assistance of a therapist. The findings support the potential of MyoGuide for wrist extension training in patients across a wide range of impairment levels. However, certain usability challenges, such as donning/doffing the armband and navigating the application, need to be addressed to enable independent MyoGuide training requiring only minimal supervision by a therapist.

Oral health-related quality of life and reasons for discontinuing partial removable dental prosthesis usage: a cross-sectional study with one to seven years of follow-up

BackgroundIn partial edentulous individuals, a partial removable dental prosthesis (PRDP) is a common dental replacement option to improve oral function and quality of life. However, some patients discontinue using their denture over time. The aim of this study was to determine the prevalence and characteristics of partial edentulous patients who no longer wear their dentures, explore their reasons, and assess their oral health-related quality of life (OHRQoL).MethodologyThis cross-sectional study, conducted at Chulalongkorn University Dental School from 2013 to 2019, involved patients who received PRDP treatment. They were contacted via phone calls and asked about their denture usage. Eligible participants were patients who had stopped or rarely used their PRDPs. Data on oral status, health insurance, and PRDP variables were collected from hospital records. Telephone interviews were conducted to collect the initial reasons for seeking PRDP treatment, reasons for discontinuation, desire for a new PRDP, and OHRQoL. The Oral Impacts on Daily Performances index was used to assess the OHRQoL. The score was dichotomized into the absence or presence of oral impacts. Chi-square tests and multivariable binary logistic regression were employed to determine the associations between oral impacts and various factors in the participants who discontinued PRDP usage.ResultsAmong the 975 contacted participants, 175 (17.9%) discontinued using their PRDPs. Most of these individuals had at least 20 remaining natural teeth and/or 4 posterior occluding pairs. The primary initial reason for seeking PRDP treatment was often based on a dentist’s suggestion. Although many participants reported no impact on OHRQoL and did not express the need for new PRDPs, those experiencing oral impacts were more likely to seek replacements.ConclusionsWith up to 7 years follow-up duration, individuals with partial edentulism and sufficient remaining functional dentition without oral impacts were more inclined to discontinue PRDP usage. Those with maxillary anterior teeth loss were less likely to discontinue using their PRDP. The primary initial reason for seeking PRDP treatment was often a dentists’ suggestion. However, the individuals reporting oral impacts expressed their needs for new denture replacements. This highlights the significance of incorporating patient needs and preferences in prosthodontic decision-making.

STUDY OF PATIENTS' QUALITY OF LIFE AS AN ALTERNATIVE TO AN ADDITIONAL DIAGNOSTIC METHOD IN THE EXAMINATION OF PATIENTS WITH DISLOCATED TEMPOROMANDIBULAR JOINT DISKS

"Quality of life is a concept used to assess and measure the level of satisfaction, health, comfort and general well-being of a person or group of people".&#x0D; The aim of the study was to investigate the QOL indicators of patients with dislocated TMJ articular discs during examination and treatment.&#x0D; The objective of this study is to determine the impact on the QOL of patients' orthopedic treatment of TMJ disc dislocations.&#x0D; The number of examined patients was 50, age 25 to 60 years, patients had a dislocated TMJ disk.&#x0D; In this study, we compared the QOL indicators in patients with dislocated TMJ discs before and after treatment, using the WHO QOL-100 questionnaire.&#x0D; The results of the study showed that the average score of the perception of overall quality of life and health (G) after treatment improved significantly. The study was divided into spheres: "Physical sphere" fatigue has significantly decreased, the feeling of pain and discomfort has disappeared, sleep has normalized, energy and strength have increased; "Psychological sphere" feelings and thinking have become more positive, concentration, self-esteem and appearance have improved, and anxiety has decreased; "Level of independence" increased daily activity and performance; "Social relationships" improved perception of relationships in society; "Environment" normalized general health of patients; in the "Spiritual sphere" patients became more confident.&#x0D; Thus, after orthopedic treatment of TMJ articular disc dislocations, QOL of patients improves significantly. The study of QOL in patients in the treatment of TMJ dislocations can be used as a diagnostic criterion for patient recovery.&#x0D; Directions for future research: the use of QOL research in assessing the quality of care of orthopedic dentists in the treatment of patients with TMJ dislocations.

Improving the simulations of the hydrological model in the karst catchment by integrating the conceptual model with machine learning models

Hydrological modelling can be complex in nonhomogeneous catchments with diverse geological, climatic, and topographic conditions. In this study, an integrated conceptual model including the snow module with machine learning modelling approaches was implemented for daily rainfall-runoff modelling in mostly karst Ljubljanica catchment, Slovenia, which has heterogeneous characteristics and is potentially exposed to extreme events that make the modelling process more challenging and crucial. In this regard, the conceptual model CemaNeige Génie Rural à 6 paramètres Journalier (CemaNeige GR6J) was combined with machine learning models, namely wavelet-based support vector regression (WSVR) and wavelet-based multivariate adaptive regression spline (WMARS) to enhance modelling performance. In this study, the performance of the models was comprehensively investigated, considering their ability to forecast daily extreme runoff. Although CemaNeige GR6J yielded a very good performance, it overestimated low flows. The WSVR and WMARS models yielded poorer performance than the conceptual and hybrid models. The hybrid model approach improved the performance of the machine learning models and the conceptual model by revealing the linkage between variables and runoff in the conceptual model, which provided more accurate results for extreme flows. Accordingly, the hybrid models improved the forecasting performance of the maximum flows up to 40 % and 61 %, and minimum flows up to 73 % and 72 % compared to the CemaNeige GR6J and stand-alone machine learning models. In this regard, the hybrid model approach can enhance the daily rainfall-runoff modelling performance in nonhomogeneous and karst catchments where the hydrological process can be more complicated.

Comparative thermal performance: An experimental study of self-stored U-pipe vacuum tube collectors operated in closed mode

ABSTRACT Hot water production using solar collectors is the utmost comprehensive application of solar energy. Solar water heaters are still incapable of operating in night/off-weather conditions and lacking in thermal performance. Researchers can see heat storage (thermal battery backup) as a potential solution. The novelty of this study is the fabrication and testing of newly designed U-pipe-based vacuum tube collectors (VTCs) integrated with thermal energy storage. Furthermore, Stearic acid and PEG6000 were selected as phase change materials in this study, and collectors were operated in closed mode for specially designed cases. Also, a cost analysis was evaluated for these collectors to show their economic viability. The thermal performance and economic outcomes of storage-based collectors were compared with conventional collector. Measured experimental data encompassed instantaneous inlet and outlet water temperatures, solar radiation and ambient temperature. The empirical findings showed that the maximum daily thermal performances were 69.81, 68.34%, and 61.33% obtained by stearic acid-filled collector-2, followed by PEG-filled collector-3 and conventional collector-1 at .334 LPM for case-III, respectively. Moreover, the maximum energy enhancement ratio was 6.28% for collector-2 and 6.21% for collector-3 at .5 LPM for case-II, respectively. From the economic analysis results, it was observed that the modified solar water heaters (collector-2 and collector-3) have an average levelized water heating cost of .06885 $/kWh and .06818 $/kWh, respectively, with a payback time of 5.37 and 5.15 years, which makes the modified collectors economically viable. Finally, the results indicate that the storage-based collectors can be used for applications with specific temperatures of hot water.

Estimating ground-level high-resolution ozone concentration across China using a stacked machine-learning method

Accurate estimation of ambient ozone concentrations is key to evaluating its detrimental impacts on human health and the ecological environment. While China has made strides in modeling ambient ozone exposure, nationwide modeling performance and spatial resolution need improvement. To address this, we developed an advanced three-level method, integrating multi-source data as predictors to estimate daily full-coverage ozone concentrations across China, with a 5-km spatial resolution. This modeling method employs subregional division, machine-learning models tailored to each subregion, and a stacking approach for estimate integration. This approach achieved substantial daily scale model performance, yielding R2 [root mean square error] values of 0.94, 0.83, and 0.74 [9.63 μg/m³, 16.59 μg/m³, 20.97 μg/m³] for sample-based, city-based, and temporal 10-fold cross-validation, respectively. Our modeling process identified six subregions for ground-level ozone modeling: Northeast (NE), North China Plain (NCP), Lower and Middle Reaches Plain of the Yangtze River (LRPYR), Southeast (SE), Southwest (SW), and Middle-West (MW). Among multi-source predictors, temperature and humidity are the most important modeling predictors in all subregions. Validation and comparative analyses highlighted the enhancement of overall model performance through subregional division and stacking machine-learning models, particularly for improving predictive accuracy on days without ground-level ozone data. The resultant estimates showed that high ozone exposure in 2020 was concentrated in the spring and summer. Our method and findings hold potential for improving ground-level ozone estimation and advancing ozone-related epidemiological research and environmental management.