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This article presents an analysis of levelised costs of producing hydrogen via the photovoltaic electrolysis in Australia. Eight locations (Darwin, Alice Springs, Brisbane, Perth, Sydney, Mildura, Melbourne, and Hobart) covering six climate zones in Australia are selected for the analysis. They receive varying solar radiation to produce electricity by using photovoltaic systems. In the present work, a standalone photovoltaic electrolysis and hydrogen engine system for 69 kWhe of daily electricity used is studied. Photovoltaic system is designed based on the minimum average monthly solar irradiation received for each selected location. The required photovoltaic array sizes are determined at the optimal slopes of the solar panels. By using the electricity generated from the photovoltaic, hydrogen is generated in electrolyser. The levelised cost of hydrogen was determined and found to be AU$ 6.79-10.62 kg-1. The electrolyser cost was found to be 52-55% of the life cycle cost of the system. Therefore, the cost of an electrolyser is the determinant factor for the levelised hydrogen production cost.

Metal–air batteries are a promising technology that could be used in several applications, from portable devices to large-scale energy storage applications. This work is a comprehensive review of the recent progress made in metal-air batteries MABs. It covers the theoretical considerations and mechanisms of MABs, electrochemical performance, and the progress made in the development of different structures of MABs. The operational concepts and recent developments in MABs are thoroughly discussed, with a particular focus on innovative materials design and cell structures. The classical research on traditional MABs was chosen and contrasted with metal–air flow systems, demonstrating the merits associated with the latter in terms of achieving higher energy density and efficiency, along with stability. Furthermore, the recent applications of MABs were discussed. Finally, a broad overview of challenges/opportunities and potential directions for commercializing this technology is carefully discussed. The primary focus of this investigation is to present a concise summary and to establish future directions in the development of MABs from traditional static to advanced flow technologies. A systematic analysis of this subject from a material and chemistry standpoint is presented as well.

This dataset includes data from the validation of double U-tube borehole and seasonal solar thermal energy storage system TRNSYS models. The simulated transient temperatures at various points of the systems were compared with the measured ones. To quantify the agreement between each simulated and measured temperature of interest, mean bias error (MBE), root mean square error (RMSE) and correlation coefficient (CC) were applied.

Objectives. Gastric cancer (GC) is one of the most prevalent neoplasms and a leading cause of mortality globally. To our knowledge, its relationship with dietary factors is not adequately studied and understood in the Nepalese context. This study is aimed at exploring the relationship between the possible dietary risk factors responsible for gastric cancer in Nepal. Methods. A hospital-based matched case-control study was conducted in two specialized cancer hospitals in Nepal. A total of 237 participants (79 cases and 158 controls) were included in the study. Patients diagnosed within one year (incidence case) with histologically confirmed gastric cancer were taken as cases, and healthy visitors of gastric and nongastric cancer patients without past and present history or not a suspected information of gastric cancer were included as controls. A face-to-face interview was conducted using a semi-structured food frequency questionnaire. Backward stepwise conditional logistic regression was used to estimate the magnitude of the association between the independent variables and gastric cancer. Results were presented as the crude odds ratio (COR) and adjusted odds ratio (AOR) with 95% confidence intervals (CI). A P value < 0.05 was considered statistically significant. Results. In the adjusted multivariable conditional logistic regression model, an increased risk of gastric cancer was more likely to have higher odds among those respondents who had a high consumption of processed meat (AOR=3.99, 95% CI: 0.90-17.66), preferences of a high amount of fats/oil (AOR=

The ground surface temperature changes with the diurnal cycle of solar radiation and ambient air temperature. However, the amplitude of the ground temperature variation diminishes with the increase of the depth of the ground and after a certain depth of the ground, it becomes almost constant, where is termed "undisturbed ground temperature (UGT)". At this depth, the seasonal changes of solar radiation and ambient air temperature changes will no longer affect onground temperature. It is one of the important parameters for designing of the ground heat exchangers and building energy analyses. In this study ground temperatures at various depths in Melbourne were investigated using a 40 m deep borehole instrumented with thermistors. The ground temperatures at various depths (0 m to 40 m) in Melbourne were also simulated by using three methods: Kasuda formula method, simulation (TRNSYS, Type 77), and simplified correlation (developed by Ouzzane et al. in 2015) and the results were compared with the measured data. Root mean square error (RMSE) and mean bias error (MBE)were used to validate and verify the methods. It was found that the estimated ground temperatures at 2, 21, and 40 m depths by Kasuda formula method and simulation (TRNSYS)have the same trends as that of the measured data. The measured annual temperatures of ground at 2 m depth were between 14.7°C and 19.8°C, while the temperature at 21 m and 40 m depths remained almost constant. RMSE and MBE of the simulation (TRNSYS, Type 77) were found to be 1.39°C, and -1.39°C respectively compared to measured data at 21 m depth. Based on these values, we conclude that simulation (TRNSYS, Type 77) can reliably predict the ground temperature for the selected site in Melbourne.

Following the recognition of the zero energy building concept, the zero energy mass customised houses have received more attention recently. This paper investigates the application of solar energy to achieve net zero on-site energy for space heating in a cold climate. As a case study, a cluster of 30 typical houses in Harbin, China was considered. Harbin is known for its coldest weather and longest winter among major Chinese cities. This study used TRNbuild software to model the house and consequently TRNSYS to determine the total heating load of the cluster of houses. The study focused on fulfilling the heating demand by using a ground source heat pump (GSHP) system. The total electricity consumed by the GSHP is covered by a grid-connected solar photovoltaic (PV) array. The required area of PV array to meet 100% of the annual electricity consumed by the GSHP was calculated. The results show the peak GSHP electric load required for the cluster of houses to be 99 kWhe with the total PV array area of 1961 m2. The levelised cost of electricity (LCoE) generated by the PV array was found to be US$ 0.067 (RMB 0.44) per kWhe for 30-year project life. The cost of heat distribution network, the annualised life cycle cost (ALCC), and the unit heating cost (UHC) were also estimated for the system investigated.

A seasonal solar energy storage system for space heating in cold climates is proposed. The system includes evacuated tube solar collectors integrated with double U-tube vertical borehole thermal storage coupled with a heat pump. The performance of the system is evaluated by computer simulations for a cluster of typical houses in four Asia-pacific cities: Ulaanbaatar (Mongolia), Harbin (China), Dras (India) and Lukla (Nepal). TRNSYS, a transient systems simulation program, was used to simulate the system. The typical detached house model for each city was developed based on the type of dwelling. The initial sizes of the system components were determined for the four cities. The average ground temperatures and energy balance of the system during charging and discharging modes were investigated. The seasonal heating coefficient of performance of the system in each city has been presented. The simple payback period (SPBP) of the proposed system was investigated by comparing convention system. It was found that the proposed system has the potential for fulfilling the space heating demand in cold climate cities of Asia-Pacific region.

This proposes searchable public key ciphertexts with hidden structures (SPCHS) for keyword seek as quickly as conceivable without giving up semantic security of the encoded keywords. In SPCHS, all keyword searchable ciphertexts are organized by concealed relations, and with the hunt trapdoor comparing to a keyword, the base data of the relations is unveiled to an search algorithm as the direction to locate all matching ciphertexts productively. We develop a SPCHS conspire without any preparation in which the ciphertexts have a concealed star-like structure. We end up being semantically secure in the random oracle(RO) model. The search many-sided quality of our plan is subject to the genuine number of the ciphertexts containing the questioned catchphrase, as opposed to the quantity of all ciphertexts. At last, we display a generic SPCHS development from unknown personality based encryption and impact free full-character pliable identity-based key encapsulation mechanism (IBKEM) with anonymity. We delineate two crash free full-character malleable IBKEM occasions, which are semantically secure and unknown, individually, in the RO and standard models.

Bile leaks after cholecystectomy are relatively frequent. Laparoscopic as opposed to “open” cholecystectomy is thought to carry an increased risk for biliary tract injury.1 Although leaks from the cystic duct stump (CDS) and bile duct are more frequent,2 leaks originating from aberrant bile ducts are also relatively common.3 Communicating leaks are usually managed endoscopically by biliary sphincterotomy with or without nasobiliary drain or stent placement,2,4 or by stent placement alone without sphincterotomy.5 However, noncommunicating leaks, which occur when an aberrant bile duct is severed, are not only challenging to manage endoscopically but also difficult to identify, thereby delaying treatment. 3 Although leak sites have been embolized and sclerosed transhepatically,6 surgery is the predominant therapeutic option for patients with this complication of cholecystectomy.7-9 Surgical therapy has limitations and it would be desirable if leak closure could be achieved by a less invasive endoscopic method. Two patients are described with leaks from a completely severed aberrant right hepatic ductal branch at cholecystectomy that were successfully identified and managed endoscopically.

Background and Study Aims: There have been growing concerns about the long-term sequelae of endoscopic sphincterotomy (ES). The aims of the study were to evaluate the long-term clinical outcome of ES for choledocholithiasis and to identify the predictors of recurrence. Patients and Methods: A total of 529 patients (233 men, 296 women; mean age 63, range 9–88) who underwent successful ES for choledocholithiasis were evaluated. Follow-up data were obtained retrospectively. Statistical analyses were carried out for 334 patients who had a follow-up of at least 5 years or had recurrence. Results: Immediate complications occurred in 37 patients (7 %). Follow-up data were available in 458 patients (86.6 %), of whom 280 (61.1%) were asymptomatic,127 (27.7%) died from unrelated causes without recurrence, and 51 (11.1%) had biliary symptoms and/or choledocholithiasis recurrence. Most recurrences (65%) occurred more than 2y ears following ES and were observed on multiple occasions in 13 patients (2.8 %). A bile duct diameter of 22mm or greater was found to predict recurrence. Of 190 patients with an intact gallbladder, 11 (5.8 %) developed acute cholecystitis necessitating emergency cholecystectomy; all of these had previously documented gallstones. Conclusions: Endoscopic sphincterotomy for choledocholithiasis is found to be safe at long-term follow-up. A dilated bile duct (‡ 22 mm) is a marker for patients at increased risk of recurrence of symptoms and/or choledocholithiasis.