Due to the accumulation of manufacturing errors of components and construction errors, there are always deviations between an as-built complex tubular engineering structure (CTES) and its as-designed ...model. As terrestrial laser scanning (TLS) provides accurate point cloud data (PCD) for scanned objects, it can be used in the building information modeling (BIM) reconstruction of as-built CTESs for life cycle management. However, few studies have focused on the BIM reconstruction of a full-scale CTES from missing and noisy PCD. To this end, this study proposes an automated BIM reconstruction method based on the TLS for a full-scale CTES. In particular, a novel algorithm is proposed to extract the central axis of a tubular structure. An extended axis searching algorithm is applied to segment each component PCD. A slice-based method is used to estimate the geometric parameters of curved tubes. The proposed method is validated through a full-scale CTES, where the maximum error is 0.92 mm.
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•Jackfruit by-products shows the potential to produce nanoparticles.•Nanoparticles with hybrid palm oil have high uniformity.•Cellular antioxidant activity of nanoparticles surpassed ...the free oil.•Nanoparticles exhibited no cytotoxic effects on differentiated Caco-2 cells.
Hybrid crude palm oil (HCPO) HIE OxG is notable for its abundance of carotenoids, tocopherols, and tocotrienols. Investigating cellular antioxidant activity (CAA) and the non-cytotoxicity of oil nanoparticles is crucial for understanding the behavior of these phytochemicals in biological systems and ensuring the safety of products. Nanoparticles of HCPO, encapsulated with jackfruit by-products were produced and characterized for CAA and cytotoxicity in Caco-2 cells. The nanoparticles exhibited nanoscale diameters (<250 nm), uniform distribution and stability (polydispersity index < 0.25; zeta potential JSF-NP −12.46 ± 0.15 mV and JAF-NP −13.73 ± 1.28 mV). JSF-NP and JAF-NP demonstrated superior CAA compared to the free HCPO across all concentrations, without inducing cytotoxic effects on differentiated Caco-2 cells. This study underscores the importance of investigating the CAA of edible oil nanoparticles, with non-cytotoxicity indicating biological safety and the potential to safeguard intestinal epithelial cells. Thus, JSF-NP and JAF-NP emerge as promising delivery systems for future HCPO applications.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
A full understanding of the Asian dust cycle can help with evaluation of the profound impact of mineral dust on human health, the ecosystem, the terrestrial and oceanic biogeochemical cycles, and the ...weather and climate. The Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP)-based 3-D dust detection and routine sampling capability, with the accurate dust mass extinction efficiency from Dust Constraints from joint Observational-Modelling-experimental analysis (DustCOMM) dataset, has made it possible to estimate the climatology of Asian dust mass loading (DML) and its transport flux. This study draws on this to provide new insights into the Asian dust cycle, especially the variability of its mass-weighted dust transport central axis (TCA), the contribution of different desert sources to its downstream effects, and the resulting dust budgets in terrestrial and oceanic regions. Dust aerosols emitted from the East Asian and Central Asian deserts together form a heavy dust transport belt stretching from the Taklimakan Desert (TD) and Gobi Desert (GD) to the Pacific Ocean. South Asian dust from the Thar Desert (ThD) can also affect southern China by crossing the Hengduan Mountains and the Yunnan-Guizhou Plateau. The dust TCA is controlled by the terrain of northwest inland China, but shifts in remote regions in the range of 35-50°N due to the western Pacific subtropical high and Aleutian low, and it trend towards a zonal straight line as the altitude increases. The dust transport contribution of the East Asian deserts to the mainland of China and adjacent sea is about 7 times than that of South Asia, with the annual transport fluxes being 214.28 and 30.43 Tg, respectively. The GD dominates the contribution of Asian deserts to the downstream effects and accounts for about 60% of the dust. This can be attributed to its maximum transport flux being near the surface, while the dust transport of the TD and ThD is above 3 km because of the blocking effect of the surrounding terrain. The deposition of Asian dust in the adjacent seas decreases significantly along the dust TCA, with the annual deposition rates being about 40.12, 20.41, and 4.01 g m-2 in the Yellow Sea, Japan Sea and the Northwest Pacific Ocean, respectively. These new findings and quantification of the Asian dust cycle will help with validation of the simulations provided by global and regional climate models and enable further evaluation of the impact of Asian dust on various related Earth systems.
•Asian dust transport flux and its contributor are firstly estimated using satellite.•East Asian deserts produce 88% of dust in mainland China and adjacent seas.•Gobi Desert is the largest downstream contributor of dust aerosol at 145.88 Tg y-1.•Dust transport flux from South Asia to the southern China is about 30.43 Tg y-1.•Asian dust outflow settles most in the Yellow Sea, with a value of 40 g m-2 y-1.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The paper refers to a process for forming the crown of the apple tree in the form of a slender spindle with a vertical central axis, weakly curved and well branched, with a single level of ...semiskeletal branches and fruiting branches. The Granny Smith variety was used, grafted onto the M9 rootstock and planted at a distance of 3.2 x 0.8 m. Before planting, a trellis was installed and 5 wires spaced 50, 80, 160, 240, 320 cm from the ground were fixed. The process of training the central axis includes: the bending of the vigorous axis and its fixation in horizontal position in spring in the first year after planting at the onset of the bud opening; the selection of an extension shoot of the central axis and pruning of vertical shoots at the collar when they reach a length of 20-25 cm; the fixation of the extension shoot in vertical position, in July.
The transpedicular procedure has been widely used in spinal surgery. The determination of the best entry point is the key to perform a successful transpedicular procedure. Various techniques have ...been used to determine this point, but the results are variable. This study was carried out to determine the posterior endpoint of the lumbar pedicle central axis on the standard anterior-posterior (AP) fluoroscopic images. Computer-aided design technology was used to determine the pedicle central axis and the posterior endpoint of the pedicle central axis on the posterior aspect of the vertebra. The standard AP fluoroscopic image of the lumbar vertebral models by three-dimensional printing was achieved. The endpoint projection on the AP fluoroscopic image was determined in reference to the pedicle cortex projection by the measurements of the angle and distance on the established X-Y coordinate system of the radiologic image. The projection of posterior endpoint of the lumbar pedicle central axis were found to be superior to the X-axis of the established X-Y coordinate system and was located on the pedicle cortex projection on the standard AP fluoroscopic image of the vertebra. The projection point was distributed in different sectors in the coordinate system. It was located superior to the X-axis by 18° to 26° at L1, while they were located superior to the X-axis by 12° to 14° at L2 to L5. The projections of posterior endpoints of the lumbar pedicle central axis were located in different positions on the standard AP fluoroscopic image of the vertebra. The determination method of the projection point was helpful for selecting an entry point for a transpedicular procedure with a fluoroscopic technique.
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Global inspection of large-scale tunnels is a fundamental yet challenging task to ensure the structural stability of tunnels and driving safety. Advanced LiDAR scanners, which sample tunnels into 3D ...point clouds, are making their debut in the Tunnel Deformation Inspection (TDI). However, the acquired raw point clouds inevitably possess noticeable occlusions, missing areas, and noise/outliers. Considering the tunnel as a geometrical sweeping feature, we propose an effective tunnel deformation inspection algorithm by extracting the global spatial axis from the poor-quality raw point cloud. Essentially, we convert tunnel axis extraction into an iterative fitting optimization problem. Specifically, given the scanned raw point cloud of a tunnel, the initial design axis is sampled to generate a series of normal planes within the corresponding Frenet frame, followed by intersecting those planes with the tunnel point cloud to yield a sequence of cross sections. By fitting cross sections with circles, the fitted circle centers are approximated with a B-Spline curve, which is considered as an updated axis. The procedure of “circle fitting and B-SPline approximation” repeats iteratively until convergency, that is, the distance of each fitted circle center to the current axis is smaller than a given threshold. By this means, the spatial axis of the tunnel can be accurately obtained. Subsequently, according to the practical mechanism of tunnel deformation, we design a segmentation approach to partition cross sections into meaningful pieces, based on which various inspection parameters can be automatically computed regarding to tunnel deformation. A variety of practical experiments have demonstrated the feasibility and effectiveness of our inspection method.
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An automated method for tunnel deformation monitoring using high density point clouds data is presented. Firstly, the 3D point clouds data are converted to two-dimensional surface by projection on ...the XOY plane, the projection point set of central axis on XOY plane named Uxoy is calculated by combining the Alpha Shape algorithm with RANSAC (Random Sampling Consistency) algorithm, and then the projection point set of central axis on YOZ plane named Uyoz is obtained by highest and lowest points which are extracted by intersecting straight lines that through each point of Uxoy and perpendicular to the two -dimensional surface with the tunnel point clouds, Uxoy and Uyoz together form the 3D center axis finally. Secondly, the buffer of each cross section is calculated by K-Nearest neighbor algorithm, and the initial cross-sectional point set is quickly constructed by projection method. Finally, the cross sections are denoised and the section lines are fitted using the method of iterative ellipse fitting. In order to improve the accuracy of the cross section, a fine adjustment method is proposed to rotate the initial sectional plane around the intercept point in the horizontal and vertical direction within the buffer. The proposed method is used in Shanghai subway tunnel, and the deformation of each section in the direction of 0 to 360 degrees is calculated. The result shows that the cross sections becomes flat circles from regular circles due to the great pressure at the top of the tunnel
This paper presents a novel framework to extract metro tunnel cross sections (profiles) from Terrestrial Laser Scanning point clouds. The entire framework consists of two steps: tunnel central axis ...extraction and cross section determination. In tunnel central extraction, we propose a slice-based method to obtain an initial central axis, which is further divided into linear and nonlinear circular segments by an enhanced Random Sample Consensus (RANSAC) tunnel axis segmentation algorithm. This algorithm transforms the problem of hybrid linear and nonlinear segment extraction into a sole segmentation of linear elements defined at the tangent space rather than raw data space, significantly simplifying the tunnel axis segmentation. The extracted axis segments are then provided as input to the step of the cross section determination which generates the coarse cross-sectional points by intersecting a series of straight lines that rotate orthogonally around the tunnel axis with their local fitted quadric surface, i.e., cylindrical surface. These generated profile points are further refined and densified via solving a constrained nonlinear least squares problem. Our experiments on Nanjing metro tunnel show that the cross sectional fitting error is only 1.69 mm. Compared with the designed radius of the metro tunnel, the RMSE (Root Mean Square Error) of extracted cross sections’ radii only keeps 1.60 mm. We also test our algorithm on another metro tunnel in Shanghai, and the results show that the RMSE of radii only keeps 4.60 mm which is superior to a state-of-the-art method of 6.00 mm. Apart from the accurate geometry, our approach can maintain the correct topology among cross sections, thereby guaranteeing the production of geometric tunnel model without crack defects. Moreover, we prove that our algorithm is insensitive to the missing data and point density.
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Background: The gold standard for burn scar reconstruction is to utilize adjacent skin flaps for the ease of operation and to match the skin characteristics. The objective of this study is to share ...our experiences using propeller flap cover for "postburn contracture of axilla (PBCA)" release reconstruction.
Materials and Methods: This 5-year retrospective observational study was undertaken in the Plastic Surgery Department of GMCH, Guwahati, from 2016 to 2020 with the data available after obtaining the Ethics Committee approval. The patient records and photographs were gathered from the Medical Records and the Plastic Surgery Department of GMCH, Guwahati, respectively. Patients treated with a propeller flap cover were scrutinized.
Results: The patients operated for PBCA were 36. There were 12 males and 14 females with a mean age of 21 years. Twelve patients with spared axillary dome skin underwent a central axis subcutaneous pedicle propeller flap. The flaps had dimensions of 8-12 cm in length and 6-9 cm in width. The pedicle was approximately 2-2.5 cm in diameter. The few complications seen included wound dehiscence and delayed wound healing, edge hypertrophy, band contractures, marginal necrosis, and pin cushioning. During follow-up, no recontractures were seen.
Conclusions: We conclude that central axis subcutaneous pedicle propeller flap is a simple and effective treatment for mild-to-moderate PBCA with spared axillary dome skin. These flaps provide durable soft tissue cover with enhanced flap survival, functional mobility, and esthetics.
The adaptive reuse of architectural heritage is the basis of embodying its core value, bringing new life to heritage architecture, and is an important way to integrate it into contemporary ...development. In many current studies, the adaptive reuse of architectural heritage focuses on the research framework of adaptive reuse and the most effective method for adaptive reuse of a certain building. In the whole process, the post evaluation strategy of adaptive reuse based on specific cultural background is ignored, and the adaptive reuse of heritage buildings is a dynamic process. Therefore, this study takes 9 heritage sites along the central axis of Beijing (including three types of single buildings, architectural complexes, and historical and cultural district) as examples. The 25 factors affecting the adaptive reuse of architectural heritage are extracted by the literature retrieval method, and are divided into three categories according to the content: existing fabric, spatial character and policy and value. Then the analytic hierarchy process and fuzzy comprehensive evaluation are used to calculate the factors of 9 heritage sites in matrix, and finally obtain the reuse score of each heritage site. The results show that Meridian Gate has the highest comprehensive score for reuse in single buildings, the Forbidden City has the highest score for reuse in building complex, and Qianmen Street has the highest score in historical and cultural district. This study provides post-evaluation methods and strategies for the adaptive reuse of architectural heritage. Finally, a post-evaluation framework for the adaptive reuse of architectural heritage is formed. Finally, a post-evaluation framework for the reuse of architectural heritage against a specific cultural background has been formed. In the future, the status of the reuse of architectural heritage can be evaluated to maintain its proper authenticity, integrity and sustainability at any time. It can also guide the relevant decision-making before the adaptive reuse of architectural heritage and the optimization process after the adaptive reuse of architectural heritage.
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