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The mass loss of the Greenland Ice Sheet is nearly equally partitioned between a decrease in surface mass balance from enhanced surface melt and an increase in ice dynamics from the acceleration and retreat of its marine-terminating glaciers. Much uncertainty remains in the future mass loss of the Greenland Ice Sheet due to the challenges of capturing the ice dynamic response to climate change in numerical models. Here, we estimate the sea level contribution of the Greenland Ice Sheet over the 21st century using an ice-sheet wide, high-resolution, ice-ocean numerical model that includes surface mass balance forcing, thermal forcing from the ocean, and iceberg calving dynamics. The model is calibrated with ice front observations from the past eleven years to capture the recent evolution of marine-terminating glaciers. Under a business as usual scenario, we find that northwest and central west Greenland glaciers will contribute more mass loss than other regions due to ice front retreat and ice flow acceleration. By the end of century, ice discharge from marine-terminating glaciers will contribute 50 ± 20% of the total mass loss, or twice as much as previously estimated although the contribution from the surface mass balance increases towards the end of the century.

This study aims to propose a method for constructing basic digital twin data in South Korea by adhering to international standards and by utilizing publicly available data. Specifically, the study focuses on designing and proposing a digital twin data model for buildings, as building-related digital twin data are the most applicable among the basic digital twin data. To achieve this, the first section provides essential background information, introduces concepts and requirements related to basic digital twin data, and offers a brief overview of City Geography Markup Language (CityGML). The second section explains the methodology and the data used in this study. The third section presents the main findings: the selection of public data (building data) for constructing basic digital twin data, the mapping process using CityGML, and the creation of Unified Modeling Language (UML) diagrams. The fourth section discusses these findings. Finally, the conclusion and recommendations for future research are provided. This approach enhances the accuracy of building-related digital twin data and supports the use of digital twin services in both public and private sectors by enabling various spatial analyses.

Calving-front dynamics is an important control on Greenland's ice mass balance. Ice front retreat of marine-terminating glaciers may, for example, lead to a loss in resistive stress, which ultimately results in glacier acceleration and thinning. Over the past decade, it has been suggested that such retreats may be triggered by warm and salty Atlantic Water, which is typically found at a depth below 200–300 m. An increase in subglacial water discharge at glacier ice fronts due to enhanced surface runoff may also be responsible for an intensification of undercutting and calving. An increase in ocean thermal forcing or subglacial discharge therefore has the potential to destabilize marine-terminating glaciers along the coast of Greenland. It remains unclear which glaciers are currently stable but may retreat in the future and how far inland and how fast they will retreat. Here, we quantify the sensitivity and vulnerability of marine-terminating glaciers along the northwest coast of Greenland (from 72.5 to 76∘ N) to ocean forcing and subglacial discharge using the Ice Sheet System Model (ISSM). We rely on a parameterization of undercutting based on ocean thermal forcing and subglacial discharge and use ocean temperature and salinity from high-resolution ECCO2 (Estimating the Circulation and Climate of the Ocean, Phase II) simulations at the fjord mouth to constrain the ocean thermal forcing. The ice flow model includes a calving law based on a tensile von Mises criterion. We find that some glaciers, such as Dietrichson Gletscher or Alison Glacier, are sensitive to small increases in ocean thermal forcing, while others, such as Illullip Sermia or Cornell Gletscher, are remarkably stable, even in a +3 ∘C ocean warming scenario. Under the most intense experiment, we find that Hayes Gletscher retreats by more than 50 km inland by 2100 into a deep trough, and its velocity increases by a factor of 3 over only 23 years. The model confirms that ice–ocean interactions can trigger extensive and rapid glacier retreat, but the bed controls the rate and magnitude of the retreat. Under current oceanic and atmospheric conditions, we find that this sector of the Greenland ice sheet alone will contribute more than 1 cm to sea level rise and up to 3 cm by 2100 under the most extreme scenario.

Calving is an important mechanism that controls the dynamics of marine terminating glaciers of Greenland. Iceberg calving at the terminus affects the entire stress regime of outlet glaciers, which may lead to further retreat and ice flow acceleration. It is therefore critical to accurately parameterize calving in ice sheet models in order to improve the projections of ice sheet change over the coming decades and reduce the uncertainty in their contribution to sea-level rise. Several calving laws have been proposed, but most of them have been applied only to a specific region and have not been tested on other glaciers, while some others have only been implemented in 1-D flowline or vertical flowband models. Here, we test and compare several calving laws recently proposed in the literature using the Ice Sheet System Model (ISSM). We test these calving laws on nine tidewater glaciers of Greenland. We compare the modeled ice front evolution to the observed retreat from Landsat data collected over the past 10 years, and assess which calving law has better predictive abilities for each glacier. Overall, the von Mises tensile stress calving law is more satisfactory than other laws for simulating observed ice front retreat, but new parameterizations that better capture the different modes of calving should be developed. Although the final positions of ice fronts are different for forecast simulations with different calving laws, our results confirm that ice front retreat highly depends on bed topography, irrespective of the calving law employed. This study also confirms that calving dynamics needs to be 3-D or in plan view in ice sheet models to account for complex bed topography and narrow fjords along the coast of Greenland.

A disc-on-disc type tester was used to examine the role of fullerene nanoparticles dispersed in a mineral oil-based lubricant. In the friction test, the friction coefficient of the disc specimen immersed in the nano-oil was significantly lower than that of the disc specimen immersed in the mineral oil. This suggests that the nanoparticles dispersed in mineral oil played the important role in the lubrication enhancement of nano-oil. A series of experiments in this study were carried out to delineate the two effects [i.e., direct effect (e.g., rolling/sliding/filming) and surface enhancement effect (e.g., mending/polishing)] of nanoparticles for nano-oil-based lubrication enhancement. The disc specimens immersed in the nano-oils during the friction test was removed, and then they were re-immersed in new mineral oil for an additional friction test. The direct and surface enhancement effect of nanoparticles was then visualised by the evolution of the friction coefficient of the disc specimen immersed in the mineral- and nano-oil. The results showed that the direct effect of nanoparticles was much more dependent on the magnitude of the applied normal load than the surface enhancement effect.

In South Korea, to systematically share and operate data related to the national level of the digital twin, a reference model standard for the National Digital Twin (NDT) concept was established in 2021. This was followed by the Korean Industrial Standards (KS) for buildings. Despite these efforts, the implementation of digital twin projects faces challenges owing to a low level of understanding of the standards and the absence of a standardized data construction process. Consequently, data construction that adheres to these standards is not being accomplished. Additionally, a lack of understanding of data models, semantic elements, and GML editing methods has led to the creation of appearance-focused data. To address these issues, this study proposes a digital twin data (building domain) construction guide that organizes geometric information, semantic information, and attribute information for building-related digital twin data components. This study aims to enable stakeholders to easily construct fundamental digital twin data in accordance with the standards, ensuring high-quality product creation that meets the requirements. Furthermore, the detailed data construction requirements defined in this guide will allow it to serve as a manual usable by both the public and private sectors. However, the proposed data model currently operates at a conceptual and logical level, which may limit its immediate applicability. Therefore, future research should include expert evaluations of the model and its transformation into a physical model that can be implemented and deployed on the relevant platform.

Background Recurrent ovarian cancer is often treated with chemotherapy, but many patients experience multiple recurrences with progressively shorter intervals and poorer prognosis. Repeated chemotherapy reduces patients’ quality of life. Stereotactic Ablative Radiation Therapy for Recurrent Ovarian Cancer (SABR-ROC) (KGOG3064/KROG 2204) is an ongoing trial investigating the clinical efficacy of stereotactic ablative radiation therapy (SABR) for recurrent ovarian cancer. This study aimed to assess treatment planning consistency and protocol adherence in a prospective, randomized, multicenter phase III trial. Methods In this dummy run study of a prospective, randomized, multicenter phase III trial (SABR-ROC), we examined the variability in target delineation, dose prescription, and treatment planning among 10 centers participating in the SABR-ROC trial. Four representative cases, each presenting with different anatomical sites and treatment challenges, were selected for evaluation. Target volume consistency was measured using the Dice similarity coefficient, and treatment plans were reviewed to follow predefined goals and constraints in the protocol. Results Overall agreement in target delineation was low, with mean Dice similarity coefficients of 0.278 and 0.255 for gross tumor volume and planning target volume, respectively. Consistency was higher for cases involving lymph node and lung metastases but significantly lower for intraperitoneal and liver seeding metastases due to challenges in target delineation. Treatment plans generally adhered to protocol dose prescriptions, with minor deviations in planning target volume coverage, particularly in cases with multiple small metastases. Deviations from organ-at-risk constraints frequently occurred in cases involving small bowel proximity. Conclusions This study highlights the challenges in standardizing SABR for recurrent ovarian cancer, particularly in achieving a consensus on target delineation and balancing treatment efficacy with organ-at-risk safety. Clinician discretion remains essential in complex cases. The insights from this study will guide the development of standardized protocols to improve outcomes and reduce adverse effects in patients with recurrent ovarian cancer. Trial registration This trial was registered with ClinicalTrials.gov under the identifier NCT05444270 on June 29, 2022.

Water-repellent soils have a potential as alternative construction materials that will improve conventional geotechnical structures. In this study, the potential of chemically treated water-repellent kaolin clay as a landfill cover material is explored by examining its characteristics including hydraulic and mechanical properties. In order to provide water repellency to the kaolin clay, the surface of clay particle is modified with organosilanes in concentrations (CO) ranging from 0.5% to 10% by weight. As the CO increases, the specific gravity of treated clay tends to decrease, whereas the total organic carbon content of the treated clay tends to increase. The soil-water contact angle increases with an increase in CO until CO = 2.5%, and then maintains an almost constant value (≈134.0°). Resistance to water infiltration is improved by organosilane treatment under low hydrostatic pressure. However, water infiltration resistance under high hydrostatic pressure is reduced or exacerbated to the level of untreated clay. The maximum compacted dry weight density decreases with increasing CO. As the CO increases, the small strain shear modulus increases, whereas the effect of organosilane treatment on the constrained modulus is minimal. The results indicate that water-repellent kaolin clay possesses excellent engineering characteristics for a landfill cover material.

To determine inter-observer variability in target volume definition of cervical cancer in radical and adjuvant radiotherapy (RT) settings. Eight physicians contoured CTVs of 2 patients underwent definitive and postoperative RT. Each volume was analyzed using the individual/median volume ratio and generalized conformity index (CIgen). And center of mass (COM) of each contour was calculated. Expert agreement was quantified using an expectation maximization algorithm for Simultaneous Truth and Performance Level Estimation (STAPLE). For definitive RT, the individual/median volume ratio ranged from 0.51 to 1.41, and CIgen was 0.531. Mean 3-dimensional distances of average to each COM were 7.8 mm. For postoperative RT setting, corresponding values were 0.65-1.38, 0.563, and 5.3 mm. Kappa value of expert agreement was 0.65 and 0.67, respectively. STAPLE estimates of the sensitivity, specificity, and kappa measures of inter-physician agreement were 0.73, 0.98, and 0.65 for the definitive and 0.75, 0.98, and 0.67 for the adjuvant radiotherapy setting. The largest difference was observed in the superior-inferior direction, particularly in the upper vagina and the common iliac area. As there was still some variability in target delineation, more detailed guidelines for target volume delineation and continuing education would help to reduce this uncertainty.

A stretchable printed circuit board (PCB), which is an essential component of next-generation electronic devices, should be highly stretchable even at high levels of integration, as well as durable under repetitive stretching and patternable. Herein, an island-structured stretchable PCB composed of materials with controlled Young’s modulus and viscosity by adding a reinforcing agent or controlling the degree of crosslinking is reported. Each material was fabricated with the most effective structures through a 3D printer. The PCB was able to stretch 71.3% even when highly integrated and was patterned so that various components could be mounted. When fully integrated, the stress applied to the mounted components was reduced by 99.9% even when stretched by over 70%. Consequently, a 4 × 4 array of capacitance sensors in a stretchable keypad demonstration using our PCB was shown to work, even at 50% stretching of the PCB.