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Background: The incidence of non-palpable breast cancer is increasing due to widespread screening and neo-adjuvant therapies. Among the available tumor localization techniques, radio-guided occult lesion localization (ROLL) has largely replaced wire-guided localization (WGL). The aim of this study was to compare the ROLL and WGL techniques in terms of the effectiveness of isotopic marking of axillary sentinel lymph nodes and to assess patient perspectives along with surgeon and radiologist preferences. Methods: A single-center, prospective, randomized study enrolled 110 patients with non-palpable breast lesions (56 ROLL, 54 WGL). Breast type, tumor volume, location, histological and radiological features, and localization/surgical duration were evaluated in the context of sentinel lymph node marking using isotope (technetium-99m-labeled human serum albumin) and blue dye. Statistical analysis was performed with significance set at p < 0.05 and strong significance at p < 0.01. Results: A single-center, prospective, randomized study enrolled 110 patients with non-palpable breast lesions (56 ROLL, 54 WGL). Breast type, tumor volume, location, histological and radiological features, and localization/surgical duration were evaluated in the context of sentinel lymph node marking using isotope (technetium-99m-labeled human serum albumin) and blue dye. Statistical analysis was performed with significance set at p < 0.05 and strong significance at p < 0.01. Conclusions: While ROLL provided advantages in terms of patient comfort and logistical simplicity, WGL was superior for axillary sentinel lymph node marking, particularly in inner quadrant tumors, suggesting that WGL may be preferred in these cases. [ABSTRACT FROM AUTHOR]

The maximum diving depth of modern submarines has always been increasing. Although this has been useful and in some cases necessary, it usually comes with some risks. For instance, when a submarine encounters an emergency situation that requires immediate ascent from great depths, the situation becomes more dangerous, especially due to its rolling characteristics. To investigate the effect of unsteady forces during free ascent motion of submarines at great depths on submarine rolling, in this study, the SST-DDES model combined with the overset grid technique was used for the numerical simulation of a submarine free ascent. Water tank experiments for free ascent were conducted to validate the numerical approach, which confirmed the reliability of the numerical method. Following this, the CFD method was employed to conduct an initial exploratory investigation into the free ascent motion of deep-submergence submarines. The free ascent motion of submarines at great depths under five different degrees of freedom combinations was studied. The computational results indicated that submarines are more prone to roll over during free ascent at great depths. At a depth six times the length of the submarine, the maximum roll angle underwater reaches 22.8°. In addition, unsteady rolling moments, lateral forces, and yawing moments have a significant effect on submarine rolling, intensifying the tendency to roll. Furthermore, it was observed that the vertical hydrodynamic attack angle β is related to the rolling stability of the submarine, such that a moderate decrease in β is beneficial for the rolling stability. The numerical calculation method and preliminary research findings can provide theoretical support for controlling the ascent motion of real submarines. [ABSTRACT FROM AUTHOR]

To research serious nonlinear coupling problems among aerodynamics, flight mechanics, and flight control during high maneuvers, a virtual flight testing platform has been developed for a large-scale, high-speed wind tunnel, based on the real physical environment, and it can significantly mitigate risks and reduce the costs of subsequent flight tests. The platform of virtual flight testing is composed of three-degrees-of-freedom model support, measuring devices for aerodynamic and motion parameters, a virtual flight control system, and a test model. It provides the ability to realistically simulate real maneuvers, investigate the coupling characteristics of unsteady aerodynamics and nonlinear flight dynamics, evaluate flight performance, and verify the flight control law. The typical test results of a pitch maneuver with open-loop and closed-loop control are presented, including a one-degree-of-freedom pitch motion and a two-degrees-of-freedom pitch and roll motion. The serious pitch and roll-coupled motion during a pitch maneuver at a high angle of attack is revealed, and the flight control law for decoupled control is successfully verified. The comparison of the test results and the flight data of a real pitch maneuver proves the reliability and capability of virtual flight testing. [ABSTRACT FROM AUTHOR]

Background and Objectives: Wide local excision is a common procedure in the treatment of breast cancer. Wire-guided localisation (WGL) has been the gold standard for many years; however, several issues have been identified with this technique, and therefore, wire-free techniques have been developed. This scoping review synthesises the available literature comparing wire-guided localisation with the wire-free techniques used in breast-conserving cancer surgery. Materials and Methods: Multiple databases including Pubmed and MEDLINE were used to search articles between 1 January 2000 and 31 December 2022. Terms included "breast neoplasms", "margins of excision", and "reoperation". In total, 34/256 papers were selected for review. Comparisons were made between positive margins and re-excision rates of WGL with wire-free techniques including SAVI SCOUT, Magseed, ROLL, and RSL. Pooled p-values were calculated using chi-square testing to determine statistical significance. Results: Pooled analysis demonstrated statistically significant reductions in positive margins and re-excision rates when SAVI SCOUT, RSL, and ROLL were compared with WGL. When SAVI SCOUT was compared to WGL, there were fewer re-excisions {(8.6% vs. 18.8%; p = 0.0001) and positive margins (10.6% vs. 15.0%; p = 0.0105)}, respectively. This was also the case in the ROLL and RSL groups. When compared to WGL; lower re-excision rates and positive margins were noted {(12.6% vs. 20.8%; p = 0.0007), (17.0% vs. 22.9%; p = 0.0268)} for ROLL and for RSL, respectively {(6.8% vs. 14.9%),(12.36% vs. 21.4%) (p = 0.0001)}. Magseed localisation demonstrated lower rates of re-excision than WGL (13.44% vs. 15.42%; p = 0.0534), but the results were not statistically significant. Conclusions: SAVI SCOUT, Magseed, ROLL, and RSL techniques were reviewed. Pooled analysis indicates wire-free techniques, specifically SAVI SCOUT, ROLL, and RSL, provide statistically significant reductions in re-excision rates and positive margin rates compared to WGL. However, additional studies and systematic analysis are required to ascertain superiority between techniques. [ABSTRACT FROM AUTHOR]

As a guide rail is the basic motion unit of precision equipment, the measurement of and compensation for its motion errors are important preconditions for precision machining and manufacturing. A targetless and simultaneous measurement method of three-degree-of-freedom (3-DOF) angular motion errors using digital speckle pattern interferometry (DSPI) is introduced in this paper. Based on the analysis of the sensitivity mechanism of DSPI to DOF errors and the formation mechanism of the phase fringes, the relationship between the angular motion errors and the distribution of the interferometric phases was established, and a new simultaneous measurement model of 3-DOF angular motion errors was further proposed. An optical setup based on a three-dimensional spatial-carrier DSPI with a right-angle symmetrical layout was used in the measurement system. Furthermore, repetitive tests, noise tests, and precision analysis were carried out to verify the performance of the system. The test results showed that the measurement resolution of the system was <1 μrad, which is capable of measuring the pitch angle, yaw angle, and roll angle at the submicron arc level simultaneously without target mirrors. The method has the advantages of no need to install cooperative targets and high measurement resolution, showing broad application prospects in many fields, including mechanical manufacturing, laser detection, aerospace, etc. [ABSTRACT FROM AUTHOR]

The calculation of the average sideways acceleration, based on speed and angular velocity on small roundabouts for a vehicle of up to 3.5 t gross vehicle mass, is described in this paper. Calculations of the turning radius are derived from angular velocity and an automatic selection of events, based on the lateral acceleration of the coefficient of variation within a defined time window. The calculation of the turning radius based on speed and angular velocity yields almost identical results to the calculation of the turning radius by the three-point method using GPS coordinates, as described in previous research. This means that the calculation of the turning radius, derived from the speed of GNSS/INS dual-antenna sensor and gyroscope data, yields similar results to those from the computation of the turning radius derived from the coordinates of a GNSS/INS dual-antenna sensor. The research results can be used in the development of sensors to improve road safety. [ABSTRACT FROM AUTHOR]

To reduce the pollution resulting from discarding waste plastic film and burning straw, a new method of preparing straw-reinforced LLDPE composites was developed to utilize these wastes. The straws were first laid parallel on an LLDPE film and then rolled up. The rolls containing long straws were laid into a mat and then hot-pressed into a long straw composite board (the mass of straw accounted for 60%). Slope-cutting the straw, grinding the straw, and twisting the roll were designed to improve the physical and mechanical properties of long straw composites. Among them, slope-cutting the straw combined with twisting the roll provided the best properties. Compared to the extruded straw particle composite, the composite prepared with the new method improved the tensile strength, bending strength, impact strength, and water resistance by 358%, 151%, 416%, and 81%, respectively. Slope-cutting exposed more inner surface at the end of the straw. Scanning electron microscope observations showed that the straw inner surface was more tightly bonded with the LLDPE matrix than the outer surface. Meanwhile, the integrity of the straw was retained as much as possible, and thus greatly improved the performance of the resulting composites. Dynamic mechanical analysis, differential scanning calorimetry, and thermogravimetric analysis show that the viscous deformation of the composites prepared by the new method was reduced and the rigidity was increased, and the combination of straw and LLDPE forms a dense composite material with good interfacial bonding. It greatly slowed down the degree of its pyrolysis. [ABSTRACT FROM AUTHOR]

Large-scale instability of a landslide body, sliding down a bank slope and entering water at a high speed, arouses landslide surges. Taking the water entry point as a source point, they spread rapidly to surrounding areas, increasing the danger risk of vessel passages in the water area. In this paper, adopting an orthogonal experimental design method, based on the test data, the Three Gorges Reservoir area was derived in order to calculate the height of the first wave of the bank landslide surge: to analyze the slope angle, the geological environment, the volume of the landslide surge, and the landslide surge wave steepness; to study the landslide volume effect on ship rolling and the swaying motion rule; and to explore the landslide surge in different ship rolling positions and transverse oscillation characteristics. This study can provide theoretical support for the navigation safety of ships in landslide surge waters. [ABSTRACT FROM AUTHOR]

The proposed surface water and ocean topography (SWOT) mission aims at observing short scale ocean topography with an unprecedented resolution and accuracy. Its main proposed sensor is a radar interferometer, so a major source of topography error is the roll angle: the relative positions of SWOT's antennas must be known within a few micrometers. Because reaching SWOT's stringent requirements with onboard roll values is challenging, we carried out simulations as a contingency strategy (i.e., to be ready if roll is larger than anticipated) that could be used with ground-based data. We revisit the empirical calibration algorithms with additional solving methods (e.g., based on orbit sub-cycle) and more sophisticated performance assessments with spectral decompositions. We also explore the link between the performance of four calibration methods and the attributes of their respective calibration zones: size and geometry (e.g., crossover diamonds), temporal variability (e.g., how many days between overlapping SWOT images). In general, the so-called direct method (using a single SWOT image) yields better coverage and smaller calibrated roll residuals because the full extent of the swath can be used for calibration, but this method makes an extensive use of the external nadir constellation to separate roll from oceanic variability, and it is more prone to leakages from oceanic variability on roll (i.e., true topography signal is more likely to be corrupted if it is misinterpreted as roll) and inaccurate modeling of the true topography spectrum. For SWOT's baseline orbit (21 days repeat and 10.9 days sub-cycle), three other methods are found to be complementary with the direct method: swath crossovers, external nadir crossovers, and sub-cycle overlaps are shown to provide an additional calibration capability, albeit with complex latitude-varying coverage and performance. The main asset of using three or four methods concurrently is to minimize systematic leakages from oceanic variability or measurement errors, by maximizing overlap zones and by minimizing the temporal variability with one-day to three-day image differences. To that extent, SWOT's proposed "contingency orbit" is an attractive risk reduction asset: the one-day sub-cycle overlaps of adjoining swaths would provide a good, continuous, and self-sufficient (no need for external nadirs) calibration scheme. The benefit is however essentially located at mid to high-latitudes and it is substantial only for wavelengths longer than 100 km.. [ABSTRACT FROM AUTHOR]

This work proposes a new wave-period estimation (L-dB) method based on the power-spectral-density (PSD) estimation of pitch and roll motional time series of a Doppler wind lidar buoy under the assumption of small angles (±22 deg) and slow yaw drifts (1 min), and the neglection of translational motion. We revisit the buoy's simplified two-degrees-of-freedom (2-DoF) motional model and formulate the PSD associated with the eigenaxis tilt of the lidar buoy, which was modelled as a complex-number random process. From this, we present the L-dB method, which estimates the wave period as the average wavelength associated to the cutoff frequency span at which the spectral components drop off L decibels from the peak level. In the framework of the IJmuiden campaign (North Sea, 29 March–17 June 2015), the L-dB method is compared in reference to most common oceanographic wave-period estimation methods by using a TriaxysTM buoy. Parametric analysis showed good agreement (correlation coefficient, ρ = 0.86, root-mean-square error (RMSE) = 0.46 s, and mean difference, MD = 0.02 s) between the proposed L-dB method and the oceanographic zero-crossing method when the threshold L was set at 8 dB. [ABSTRACT FROM AUTHOR]

CryoSat-2 is the first satellite mission carrying a high pulse repetition frequency radar altimeter with interferometric capability on board. Across track interferometry allows the angle to the point of closest approach to be determined by combining echoes received by two antennas and knowledge of their orientation. Accurate information of the platform mispointing angles, in particular of the roll, is crucial to determine the angle of arrival in the across-track direction with sufficient accuracy. As a consequence, different methods were designed in the CryoSat-2 calibration plan in order to estimate interferometer performance along with the mission and to assess the roll's contribution to the accuracy of the angle of arrival. In this paper, we present the comprehensive approach used in the CryoSat-2 Mission to calibrate the roll mispointing angle, combining analysis from external calibration of both man-made targets, i.e., transponder and natural targets. The roll calibration approach for CryoSat-2 is proven to guarantee that the interferometric measurements are exceeding the expected performance. [ABSTRACT FROM AUTHOR]

The effective production of nanopatterned films generally requires a nanopatterned roll mold with a large area. We report on a novel system to fabricate large-area roll molds by recombination of smaller patterned areas in a step-and-repeat imprint lithography process. The process is accomplished in a method similar to liquid transfer imprint lithography (LTIL). The stamp roll with a smaller area takes up the liquid resist by splitting from a donor substrate or a donor roll. The resist is then transferred from a stamp roll to an acceptor roll and stitched together in a longitudinal and, if necessary, in a circumferential direction. During transfer, the nanostructured resist is UV-exposed and crosslinked directly on the acceptor roll. The acceptor roll with the stitched and recombined stamp patterns is ready to be used as a large-area roll mold for roll-based imprinting. A system for this purpose was designed, and its operation was demonstrated taking the example of an acceptor roll of 1 m length and 250 mm diameter, which was covered by 56 patterned areas. Such a system represents an elegant and efficient tool to recombine small patterned areas directly on a large roll mold and opens the way for large-area roll-based processing. [ABSTRACT FROM AUTHOR]

The stability of FPSO or offloading shuttle tanker may be affected in wave conditions which excite parametric rolling. The offloading operations are thereby ceased and eventually leads to loss in production which affects the revenue of global production, better known as downtime cost. This paper discusses downtime cost analysis of offloading operations due to parametric rolling of shuttle tanker under regular waves in Malaysian waters for three different locations. The downtime due to parametric rolling is investigated for two different water depths for which the probability of occurrence was calculated from the location specific wave scatter diagram. The results of parametric rolling of shuttle tanker along with downtime cost charts are presented. Additionally, a Graphical User Interface (GUI) was developed and its work procedure is demonstrated in this paper. The down-time cost calculator will help the oil operator companies to analyze the economic risks involved for field developments and anticipate the loss in revenue for downtime occurrences. The developed GUI was copyrighted under literary work as intellectual property. [ABSTRACT FROM AUTHOR]

This paper proposes a system utilizing a Renishaw XL80 positioning error measuring interferometer and sensitivity analysis design to measure six-degree-of-freedom (6 DOF) geometric errors of a machine tool's linear guide. Each error is characterized by high independence with significantly reduced crosstalk, and error calculations are extremely fast and accurate. Initially, the real light path was simulated using Zemax. Then, Matlab's skew ray tracing method was used to perform mathematical modeling and ray matching. Each error's sensitivity to the sensor was then analyzed, and curve fitting was used to simplify and speed up the mathematical model computations. Finally, Solidworks was used to design the set of system modules, bringing the proposed system closer to a product. This system measured actual 6 DOF geometric errors of a machine tool's linear guide, and a comparison is made with the Renishaw XL-80 interferometer measurements. The resulting pitch, yaw, horizontal straightness, and vertical straightness error deviation ranges are ±0.5 arcsec, ±3.6 arcsec, ±2.1 μm, and ±2.3 μm, respectively. The maximum repeatability deviations for the measured guide's pitch, yaw, roll, horizontal straightness, vertical straightness, and positioning errors are 0.4 arcsec, 0.2 arcsec, 4.2 arcsec, 1.5 μm, 0.3 μm, and 3 μm, respectively. [ABSTRACT FROM AUTHOR]

Rolling back-up rolls require high fracture toughness, particularly in the shaft portion, and high-hardness in the sleeve portion. The rolls are classified into two types; one is an integrated type and the other is a shrink-fitted type consisting of a sleeve and a shaft. The shrink-fitted roll has several advantages, for example, suitable materials can be chosen and the shaft can be reused by replacing the damaged sleeve. However, during use if the residual permanent deflection occurs, the roll cannot be used anymore. In this paper, an elastic-contact finite element method FEM analysis is performed to explain the residual permanent deflection mechanism. It is found that the quasi-equilibrium stress zone with the residual displacement causes the permanent slippage in the axial direction. In a similar way, the interface creep in the circumferential direction can be also explained from the quasi-equilibrium stress zone with the residual displacement. [ABSTRACT FROM AUTHOR]