Purchase Cost Research Articles

Fabrication of a Portable Groundnut Decorticating Machine for Domestic Purpose

Groundnut is one of the important oil seed crops cultivated in India. India ranks first in groundnut area under cultivation and is the second largest producer in the world with 101 lakh tones with productivity of 1863 kg per hectare in 2021-22. Groundnut cultivation in India is done by small-scale farmersand is the predominant dryland crop. In the beginning, thepeanuts were separated from their shells by the workers and theoutput from this method was much less and could not satisfy themarket demand as it was a very time-consuming process. It is atime-consuming and tedious operation. Hence, a portablegroundnut decorticating machine is designed and fabricatedwhich is small in size, easy to carry anywhere, and very easy tooperate (at any time). This is more useful for domestic purposessuch as households, hotels, and restaurants. This paper describesabout the design and fabrication of various components of a hand-operated groundnut decorticator. Small farmers or businessmencan start businesses by investing less capital. The output is about40-42 kg/hour, shelling time taken 1.5 min/kg, and with a highcost-benefit ratio of 1:28.6. The machine is also lightweight andeasy to operate and maintain, the spare parts are also availablelocally. Maintenance is very easy, purchase cost is low, and highlyeconomical in use. No electric power or diesel or skill knowledge is required. The shelling operation can be done by women at any time by accommodating in the house itself. Small and marginalfarmers can use regular shelling for the sowing of groundnut. This is a convenient equipment and can be used at any time(during day time or night time) based on their convenience. Not much labor is required and one person can manage the decortication process it is cost effective also.

Rapid and Effective Determination of Ethyl Glucuronide in Hair by Micro Extraction by Packed Sorbent (MEPS) and LC-MS/MS.

Ethyl glucuronide (EtG) in hair is a reliable biomarker of alcohol consumption habits. Due to its small concentration incorporated into hair, analytical methods sensitive enough to reliably quantify EtG in this matrix are required. Sample preparation is critical in hair analysis, especially for EtG, for which extraction efficiency and matrix effect can strongly influence the results; furthermore, miniaturized methods are sought, to reduce solvent use and times of sample preparation. A micro extraction by packed sorbent (MEPS) procedure coupled to a high-performance liquid chromatography-tandem mass spectrometry method was developed and validated for quantitation of EtG in human hair samples. Fifty milligrams of hair samples were cut into snippets and extracted in water. The cleanup of the extract was carried out by using a MEPS syringe packed with anion exchange sorbent (SAX); all parameters for conditioning, washing, loading and eluting steps were optimized and the eluted aqueous volume was directly injected in the LC-MS/MS system operating in the negative ionization mode. The method was fully validated assessing LOD, LOQ, calibration curve, repeatability, accuracy, matrix effect and carryover. The method was subsequently applied to QCs and authentic hair samples. The developed MEPS method is quick and effective, with low solvent purchase and discard costs, allowing the differentiation between social drinkers and chronic excessive alcohol consumers, according to the cut-offs established by the Society of Hair Testing (SoHT).

Barriers to the application of simulation technologies in the education of health care students

Abstract Simulation technologies (ST) in health and medical education are undergoing rapid development due to the undoubted advantages of the methods and forms of simulation used - high quality, significant efficiency, economy, reliability and safety for the patient. At the same time, the application of ST is still underrepresented in the education of health care students. The main aim of this study was to identify the barriers and perspectives for the application of ST in the education of health professional students in Bulgaria from the perspective of the respondents’ expertise. A qualitative study of the expert (n = 17) opinion of those directly involved in the introduction, application, and evaluation of the use of ST in the education of healthcare students was conducted in 2023 in Varna. The questionnaire regarding the barriers and perspectives in the use of ST in the education of undergraduate and postgraduate students in health specialties students was used. The main barriers to the widespread use of ST in the training of students were identified as follows: the lack of adapted curricula that combine traditional practical sessions with patients and those on simulators; the lack of a sufficient number of trained and motivated trainers; the reluctance of trainers to introduce or more widely use ST; lack of or insufficient space to locate a simulation centre or equipment in relevant core units; the high cost of purchasing and maintaining ST and limited financial resources, as well as the large number of students in the groups. According to one of the experts, ‘there are no barriers to the use of ST, but real patient contact and a personalized approach to the patient is impossible to replicate through technology,’ highlighting the importance in combining traditional training with real patients and modern with the use of technology. Ethical issues in training healthcare professionals with simulators appear to be a new aspect of medical education with the application of ST. Key messages • In the effort for widespread implementation of ST in the training of health professions students, it is important to achieve a balance with traditional training experienced with real patients. • Identifying and overcoming barriers is an important prerequisite for the rapid and widespread application of ST in the training of health care students.

Flexibility-Constrained Energy Storage System Placement for Flexible Interconnected Distribution Networks

Configuring energy storage systems (ESSs) in distribution networks is an effective way to alleviate issues induced by intermittent distributed generation such as transformer overloading and line congestion. However, flexibility has not been fully taken into account when placing ESSs. This paper proposes a novel ESS placement method for flexible interconnected distribution networks considering flexibility constraints. An ESS siting and sizing model is formulated aiming to minimize the life-cycle cost of ESSs along with the annual network loss cost, electricity purchasing cost from the upper-level power grid, photovoltaic (PV) curtailment cost, and ESS scheduling cost while fulfilling various security constraints. Flexible ramp-up/-down constraints of the system are added to improve the ability to adapt to random changes in both power supply and demand sides, while a fluctuation rate of net load constraints is also added for each bus to reduce the net load fluctuation. The nonconvex model is then converted into a second-order cone programming formulation, which can be solved in an efficient manner. The proposed method is evaluated on a modified 33-bus flexible distribution network. The simulation results show that better flexibility can be achieved with slightly increased ESS investment costs. However, a large ESS capacity is needed to reduce the net load fluctuation to low levels, especially when the PV capacity is large.

Helping hampered bidders—Do subsidy auctions work as intended?

AbstractThe use of preference or discriminatory auctions, where one class of bidders is offered favored treatment over another class, has received mixed attention in the literature. Research has shown there is often an economic benefit of such policies in procurement auctions thanks to lower costs for buyers as incentives are offered to disadvantaged sellers. In this paper, we study one type of preferential procurement auction: the subsidy. Using a set of controlled experiments, we compare actual bidder behavior to what is predicted in equilibrium and find consistent (but overly aggressive) patterns overall. By testing a common bid strategy assumption, we also identify a behavioral framing bias that may trap sellers in these suboptimal strategies. Finally, we compare subsidies to another common discriminatory mechanism—the price preference—and find evidence that buyers interested in increasing the welfare of disadvantaged sellers should use subsidies instead of price preference auctions, thanks to a surprising difference in outcomes between preference types. Due to the wide use of bid preference auctions to support both policy and social aims, our findings have both financial and societal implications.

Feasibility of biogas upgrading at a WWTP after pre-treatment application: Techno-economic assessment validation with pilot test data

Improving the efficiency of anaerobic digestion (AD) of sewage sludge (SS) is a critical step toward the achievement of energy neutrality in wastewater treatment plants (WWTPs), as required by the European Green Deal. This study used a comparative techno-economic assessment (TEA) to evaluate the feasibility of producing biomethane, at a WWTP, through upgrading biogas with a double-stage permeation membrane plant. The biogas was originally generated from the AD of a mixture of primary sludge (PS) and either raw or pre-treated waste activated sludge (WAS), where biological or thermo-alkali pre-treatments were applied to increase the WAS intrinsic low degradability.The TEA was supported by the results of pilot-scale tests, carried out on WAS, which mimicked (i) a traditional mesophilic AD process; (ii) a two-stage AD process, where a temperature-phased anaerobic digestion (TPAD, 3 days, 55 °C + 20 days, 38 °C) was performed to biologically pre-treat WAS; (iii) a traditional mesophilic AD process preceded by a thermo-alkali (4 g NaOH/100 g TS, 90 °C, 90 min) pre-treatment.The TEA was carried out in two phases. In the first, the minimum size of the WWTP capable of making the costs necessary for the implementation of the biogas upgrading plant equal to the revenues coming from selling biomethane (at 62 €/MWh) in 10 years was calculated in the absence of pre-treatments. It resulted of 500,000 equivalent inhabitants (e.i.). In the second phase, for the WWTP size found previously, the effect of either biological or thermo-alkali pre-treatments on the economic balance was evaluated, that is the gain (or the loss) associated to the selling of biomethane, compared to the reference price of 62 €/MWh. It was found that the TPAD increased the biogas productivity by only 23.6%, too little to compensate the amount of heat necessary for the pre-treatment and the purchase cost of the additional reactor. Conversely, the thermo-alkali pre-treatment, which enhanced the WAS biogas productivity by 110%, increased the biomethane revenues by approx. 10 €/MWh, compared to the scenario without pre-treatments. This study offers useful data to WWTP managers who want to introduce WAS pre-treatments, combined with interventions for biogas upgrading, in a new or existing sludge line of a WWTP.

An optimization dispatching strategy for integrated electricity and natural gas systems with fast charging stations

With the increasing number of electric vehicles (EVs), a large amount of charging load will affect the safety and economic operation of the distribution network (DN). In this paper, an optimization dispatching strategy for integrated electricity and natural gas systems (IEGS) with fast charging stations (FCSs) is proposed to address the impact of fast charging loads. Firstly, the FCS load model is established based on the simulation of vehicle traveling and vehicle charging. Secondly, a natural gas supply model is established, which includes constraints such as the adjustment range, direction, and total number of supply flow adjustments. Then, an optimization dispatching strategy for IEGS based on energy storage and gas storage is proposed. Finally, the effectiveness of the proposed strategy is verified. The simulation results show that when the proposed strategy is applied, the voltage of FCS node will be stabilized within a good range. And the energy purchase cost will be reduced by more than 50%. The proposed method improves the carrying capacity of DN for FCSs.

Optimal Replenishment Strategy for a High-Tech Product Demand with Non-Instantaneous Deterioration under an Advance-Cash-Credit Payment Scheme by a Discounted Cash-Flow Analysis

This study investigated non-instantaneous deteriorating items because not all products deteriorate immediately. In the high-tech product life cycle, the product demand increases linearly substantially in the growth stage and maintains a near-constant level in the maturity stage. This is a ramp-type demand rate. To satisfy the demand as shortages occur, partial backlogging is necessary. The advance-cash-credit payment scheme, comprising advance, cash, and credit payments, has gained popularity in business transactions to improve cash flow flexibility among supply chain participants. This study explored a partial backlogging inventory model with ramp-type demand for non-instantaneous deteriorating items under generalized payment. The proposed model also incorporated discounted cash flow analysis to account for the time value of the profit function. This study attempted to determine the optimal replenishment strategy to maximize the present value of the total profit. Finally, we conducted a sensitivity analysis to examine the efficacy of the proposed model and gain managerial insights. The optimal total profit rises with an increase in the permissible delay period and sale price but decreases with an increase in ordering and purchase costs. Then, the decision-maker can refer to the managerial insights to choose the appropriate parameter value for the operation.

Evaluation of the performance of new plastic packing materials from plastic waste in biotrickling filters for odour removal

The gas emissions from wastewater treatment plants (WWTPs) contain multiple chemical compounds, such as H2S, NH3 and volatile organic compounds (VOCs), which can cause odour nuisance and health hazards. Biological technologies, such as biotrickling filters (BTFs), are preferred due to their cost-effectiveness and eco-friendliness. The selection of the packing materials in these bioreactors is crucial due to their high purchase cost, frequent replacement and impact on the gas-liquid mass transfer. This research aims at evaluating the NH3, H2S and VOC abatement performance of novel packing materials from plastic byproducts from the water cycle at different gas residence times (EBRT). The experimental set-up consisted of three BTFs of 2 L of working volume constructed with three different packing materials: commercial Pall rings (control), recycled plastic (from bottle caps), and extruded recycled plastic materials in the form of an optimised 3D-printed carrier. The three BTFs supported a complete removal of H2S and NH3 at EBRTs of 30, 15, 10 and 6 s, and VOCs removal above 90 % at EBRTs of 30 and 15 s. The extruded recycled plastic materials in the form of optimised 3D-printed carrier supported toluene and α-pinene removals of 100 % at EBRTs of 30 and 15 s. The genus Thiobacillus was identified in the three BTFs. This research confirmed the potential of reused and recycled plastics from the integral water cycle as a packing material in BTFs devoted to odour treatment.

Optimal battery electric bus system planning considering heterogeneous vehicles, opportunity charging, and battery degradation

Battery electric buses (BEBs) have been seen as a viable alternative for sustainable mobility. The charger placement and fleet configuration play a crucial role in the operational efficiency of BEBs. In this study, a joint optimization model is developed to strategically plan the charger placement and fleet configuration for a BEB system. Distinct from existing research, we simultaneously incorporate opportunity charging, heterogeneous vehicles, and battery degradation to integratively minimize the costs of charger installation, BEB purchase, energy consumption, and battery degradation. Based on a model reformulation, a heuristic-exact hybrid solution method is customized to solve the model. A real-world case study from Oslo, Norway is provided to demonstrate the optimization model and solution method. The results indicate that the proposed model can reduce the total costs by 21.27% in comparison to the conventional model. Sensitivity analyses are further conducted to provide insightful findings and managerial implications for BEB systems.

Effects of wire rope isolators on seismic life-cycle cost of UHV bypass switch

The seismic isolation devices reduce the seismic vulnerability of the electrical equipment. Accurately assessing the seismic life-cycle cost (SLCC) of the electrical equipment is beneficial in guiding the design and enhancing the seismic resilience of electrical substations and converter stations. To evaluate the effects of the isolator devices on the seismic life-cycle cost of electrical equipment, a SLCC evaluation model was proposed in this study, and the evaluation was conducted on an ultra-high voltage (UHV) bypass switch (BPS) with wire rope isolators (WRI). The model takes into account equipment purchase, maintenance, transportation and installation costs and indirect losses caused by power outages. Afterward, the SLCC and break-even time of the UHV BPS with and without WRIs in different regions were analyzed. The results indicate that beyond the break-even time, the BPS with WRIs becomes more economically viable. Moreover, its economic viability increases as the service life extends. Therefore, in high seismic cost risk areas, it is recommended to adopt seismic isolation devices to ensure the secure and economically efficient operation of electrical equipment.

Understanding the Impacts on Automobile Leasing Firm Loss in China: An Analysis of Vehicle Residual Value Risk and Lease Price Patterns

ABSTRACTThe paper addresses vehicle depreciation and pricing issues in the automobile leasing industry in China. Under the current industry climate, operating lease firms face large residual value risk, and therefore, how to price contracts that minimises such risk is an important question. By analysing market data of used vehicles, an exponential decay function was developed to model the price dynamics across different brands and model series. Specifically, we estimate the depreciation rate directly from the data. In addition, by considering all revenue and cost components and converting them into present value terms, appropriate deposit and rents combintions were sought under different profit expectations. Length of contracts, age of vehicles and purchase cost factors were also considered to detect any further patterns in rents. The research outcomes will provide guidance on lease pricing given the current development of the industry, thereby improving firms’ profitability position as well as helping maintain their competitiveness and growth.

Life cycle impact and cost analysis of quarry materials for land-based enhanced weathering in Northern California

Enhanced weathering (EW) is a CO2 removal (CDR) and sequestration strategy that accelerates the natural reactions of minerals that can store carbon from the atmosphere and biotic reactions. One method of EW is to apply finely ground silicate rocks to agricultural lands. EW has been demonstrated in laboratory and field tests, but great uncertainty remains regarding the life-cycle of using locally available rocks on candidate soils. We evaluate the life-cycle impacts, job creation, and cost of scenarios where fines and rocks mined from quarries in Oregon and Northern California are transported by truck and tilled into agricultural soils. Candidate quarry dust samples were classified as dacite, andesite, and olivine-bearing rocks, with EW potentials ranging from 125 to 760 kg CO2/metric tonne rock. We determined the olivine-bearing rock from Southern Oregon could achieve a levelized cost of CDR under the DOE Earthshot target of $100/t CO2, as long as application rates are 25 t/ha or more. Even andesite and dacite materials reach lower costs than commercial direct air capture technologies, with reduction in fines purchase and transport costs critical for achieving the Earthshot target. The results suggest that low-cost EW can be achieved using natural quarry materials, with average removal up to 2.2 t CO2e per hectare per year.

Upscaling cargo bike sharing in cities: A comparative case study

Urban mobility transitions are essential to mitigate climate change and improve the quality of life in cities. Cargo bikes (CBs) show promise in replacing motorised vehicles due to their lower carbon intensity, space efficiency, and ability to reduce air and noise pollution. CB sharing relieves users from purchase and maintenance costs. However, it is mainly adopted by individuals with high environmental awareness. Barriers to CB sharing stem from the urban infrastructure, individual mobility choices, and the design of CB sharing organisations (CBSOs). This article analyses upscaling pathways for CB sharing, i.e., increasing their use by a broader audience and reshaping the urban mobility regime. It delivers a comparative case study analysis of two CBSOs: Grätzlrad, Vienna, and LastenVelo e.V., Freiburg. Data was collected through academic and grey literature review and 15 semi-structured interviews with CB sharing stakeholders and experts. The analytical framework is informed by strategic niche management, viewing CB sharing as a niche innovation in the urban mobility regime. The article enhances understanding of CB sharing, the interaction of CBSOs with key actors, and their scalability. CBSOs should increase the availability of shared CBs while reducing the organisational effort required from users. New ways of CB sharing, e.g., integration in shared mobility hubs, should be explored. Municipal actors play a crucial role in upscaling and ensuring that CB sharing reaches a diverse user base. The findings are useful for academia, practitioners and policymakers working with CB sharing and other sustainable urban mobility solutions.

Super-resolved fluorescence imaging utilising accessible stochastic optical reconstruction microscopy (easySTORM) implemented on a low-cost, modular open-source (openFrame) microscope

Abstract Optical super-resolution microscope is a powerful tool for the life sciences, including cell biology and pathology yielding information on, e.g., biological structure and protein distribution in the nano-scale range. In recent years, there has been an exponential rise in the interest to apply super-resolution microscopes in diverse areas, but its wider utility is hindered by the cost of purchasing and maintaining super-resolved microscopes. In this paper we present the implementation of easySTORM, an accessible implementation of stochastic optical reconstruction microscopy (STORM) at Indian Institute of Technology Guwahati (IITG), India, in a flexible, user friendly and cost-effective manner using a state-of-the-art, modular, open-source, optical microscope platform called: "openFrame". Providing comparable imaging performance to commercial optical super-resolution microscopes, the openFrame-based implementation of easySTORM uses in-expensive multimode diode lasers and industry grade CMOS cameras, and the open-source and modular nature of the instrument makes it easy to maintain and to upgrade. To demonstrate its successful implementation at IITG, we image quantum dots and actin-tubulin structure in both normal and cancer cells, resolved features separated by a few tens of nanometers. This work demonstrates that openFrame-enabled easySTORM instrumentation can be widely accessible to provide affordable, research grade super-resolution microscopy capability for academic and medical research.

Inhibition of diastatic yeasts by Saccharomyces killer toxins to prevent hyperattenuation during brewing.

Secondary fermentation in beer can result in undesirable consequences, such as off-flavors, increased alcohol content, hyperattenuation, gushing, and the spontaneous explosion of packaging. Strains of Saccharomyces cerevisiae var. diastaticus are a major contributor to such spoilage due to their production of extracellular glucoamylase enzyme encoded by the STA1 gene. Saccharomyces yeasts can naturally produce antifungal proteins named "killer" toxins that inhibit the growth of competing yeasts. Challenging diastatic yeasts with killer toxins revealed that 91% of strains are susceptible to the K1 killer toxin produced by S. cerevisiae. Screening of 192 killer yeasts identified novel K2 toxins that could inhibit all K1-resistant diastatic yeasts. Variant K2 killer toxins were more potent than the K1 and K2 toxins, inhibiting 95% of diastatic yeast strains tested. Brewing trials demonstrated that adding killer yeast during a simulated diastatic contamination event could prevent hyperattenuation. Currently, most craft breweries can only safeguard against diastatic yeast contamination by good hygiene and monitoring for the presence of diastatic yeasts. The detection of diastatic yeasts will often lead to the destruction of contaminated products and the aggressive decontamination of brewing facilities. Using killer yeasts in brewing offers an approach to safeguard against product loss and potentially remediate contaminated beer.IMPORTANCEThe rise of craft brewing means that more domestic beer in the marketplace is being produced in facilities lacking the means for pasteurization, which increases the risk of microbial spoilage. The most damaging spoilage yeasts are "diastatic" strains of Saccharomyces cerevisiae that cause increased fermentation (hyperattenuation), resulting in unpalatable flavors such as phenolic off-flavor, as well as over-carbonation that can cause exploding packaging. In the absence of a pasteurizer, there are no methods available that would avert the loss of beer due to contamination by diastatic yeasts. This manuscript has found that diastatic yeasts are sensitive to antifungal proteins named "killer toxins" produced by Saccharomyces yeasts, and in industrial-scale fermentation trials, killer yeasts can remediate diastatic yeast contamination. Using killer toxins to prevent diastatic contamination is a unique and innovative approach that could prevent lost revenue to yeast spoilage and save many breweries the time and cost of purchasing and installing a pasteurizer.

Investigating the potential of a battery swapping method at refuel stations for electric vehicle: A case study of INDIA

Electric vehicles (EVs) are introduced to mitigate environmental problems and develop sustainable modes of transport across the globe. Researchers often report that the non-availability of charging infrastructure is the primary concern for EV adoption. The traditional plug-in EV charging method has a higher waiting time, discouraging users from adopting EVs. Many countries, including India, are promoting an alternative battery swapping method (BSM) for EV charging to reduce the waiting time. But the user preference and willingness to adopt BSM remain unexplored, especially in developing countries. The existing refuel stations are a potential location for developing charging infrastructure that provides the EV charging service and helps create awareness among users because of their wide visibility. Thus, this study aims to bridge the research gap by exploring the influential factors, user preferences, and willingness to use the BSM at refuel stations. For this purpose, 1013 samples were collected from road users who visited 51 refueling stations using the random sampling method in the twin cities of Ahmedabad and Gandhinagar. An integrated partial least squares-structural equation modelling with the artificial neural network method was adopted in this study. The study’s findings reveal that the development of public EV charging facilities at refuel stations significantly impacts the user’s willingness to shift to EVs. The convenience and cost-related motivating factors like a lesser waiting time compared to the plug-in charging method, reduced range anxiety, no concern about battery usage, reduced initial purchase cost of an EV, and comparatively lower maintenance costs significantly motivates user’s willingness to adopt BSM. Similarly, battery-related demotivating factors like the non-reliable range of the swapped battery, non-standard battery design in terms of type, size, capacity, and brand across the country, additional cost for leasing or renting the battery, and chances that EV batteries might be replaced with fake batteries concern BSM adoption.

Optimal low-carbon scheduling of integrated energy systems considering stepped carbon trading and source-load side resources

Under the dual-carbon goal of achieving carbon peaking and carbon neutrality, the Integrated Energy System (IES) enhances the power sector's environmental sustainability by integrating multiple energy sources. To enhance the low-carbon utilization of IES energy, this paper introduces an economic optimization model that incorporates stepwise carbon trading and both source and load-side resources. Initially, the model integrates a Concentrated Solar Power Plant (CSPP) with a Combined Heating and Power (CHP) unit for bidirectional electricity-heat conversion, and incorporates Power to Gas (P2G) and Carbon Capture System (CCS) for carbon recycling within the IES. On the demand side, demand response optimizes the electricity-heat load curve. Subsequently, a stepped carbon trading mechanism guides the system in controlling carbon emissions and constructing a carbon emission model. Finally, the model minimizes the sum of energy purchase costs, carbon transaction costs, demand response compensation costs, wind curtailment penalties, and equipment maintenance costs to optimize the IES economically. By establishing five scenarios for comparative analysis, incorporating CSPP, P2G-CCS, demand response, and a stepped carbon trading mechanism reduces system costs, carbon emissions, and abandonment rates by 21.1 %, 30.87 %, and 23.78 %, respectively, validating the model's effectiveness in promoting a low-carbon economy.

SP1.13 - An Overview of Laparoscopic Surgical Training Modalities – How Does Augmented Reality Simulation Compare?

Abstract Background Laparoscopic surgery is known to require intensive training to gain the required skills and with the increasing popularity of laparoscopic surgery over open surgery requires novel and efficient ways of training. AR is a novel introduction to laparoscopic surgical training and can superimpose digital images and physical models with the unique advantage of combining visual realism with true-to-life haptic feedback. Methods Compare different types of laparoscopic training modalities and assess how AR compares to the education system, 31 papers were systematically reviewed, and the findings were compiled. Results Both the available products as well as the technology as an educational modality were evaluated. Results Studies reported relatively increased speed of learning, improved ability to multitask, procedural accuracy, hand-eye coordination and bimanual operation in a reduced practice time and increased success rate with AR in healthcare education. One of the limitations of AR is that it doesn’t reflect the non-technical skills required in the operation. Compared with other modalities AR provided faster skill acquisition and was widely preferred, except when compared against a human cadaver model for straight laparoscopic colorectal skills acquisition. AR tends to have a higher initial purchasing cost but does not require the costly specialist facilities or services that cadaver or animal models do, 150 trusts in the NHS preliminary data is showing an estimated annual saving of £117m. Conclusion AR simulation has the potential to become the new gold standard for laparoscopic surgical training, and beyond, pending further development of literature to increase knowledge of the technology and its capabilities, on top of technological evolution to increase clinical realism.

Clean energy ship application to promote carbon neutrality in global maritime industry: State governance or international supervision？

The global maritime industry is facing the goal to achieve "carbon neutrality", and substituting traditional ship fuel with clean energy is the most important solution. Whether to promote clean-energy ships through state governance or unified international supervision to achieve carbon neutrality has been a long-standing debate. This study employs both a tripartite evolutionary game model and a quadrilateral evolutionary game model to compare the effectiveness of state governance and unified international supervision in promoting clean-energy ships. The tripartite model simulates interactions between local governments, shipping companies, and shippers, revealing that high subsidy costs reduce local governments' incentives to promote clean-energy ships. The quadrilateral model introduces international supervision, demonstrating that a unified international oversight mechanism can accelerate the global maritime industry's progress toward carbon neutrality. Numerical simulations indicate that lowering the purchase costs of clean-energy ships and introducing government subsidies significantly influence the adoption of clean-energy ships, while supervision costs impact the effectiveness of international regulations. These findings provide critical insights for policymakers aiming to balance financial incentives and global supervision strategies to foster low-carbon development in the maritime sector.