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Copyright of Electronic Components & Materials is the property of Electronic Components & Materials and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

There is a rapid development of 3D visualization (3DV) technology in the medical field nowadays. The 3DV model of the liver established by original CT and/or MRI imaging data can provide information on the complex structure of the liver in a variety of modes and help surgeons to perform better preoperative evaluation and individualized planning, so as to realize optimal protective liver resection and finally help patients get the best benefits. This article reviews the research advances in 3DV technology and precision surgery for liver tumors. [ABSTRACT FROM AUTHOR]

With the advent of the era of digital intelligent diagnosis and treatment, the clinical application of new techniques plays an important role in improving the diagnosis and treatment of pancreatic cancer. The rapid development of digital intelligent diagnosis and treatment techniques, such as three - dimensional visual simulation, three - dimensional printing, virtual reality, augmented - reality surgical navigation, and radiomics, shows the new directions of the diagnosis and treatment of pancreatic diseases and leads digital pancreatic surgery into the era of digital intelligence. With reference to related articles in China and foreign countries and the authors ’ experience in the digital intelligent diagnosis and treatment of pancreatic cancer, this article elaborates on the current application of related techniques in the diagnosis and treatment of pancreatic cancer and introduces the application of these techniques in preoperative resectability assessment, individualized surgical planning, and visual - guidance surgery for pancreatic cancer, as well as the perspectives of the digital intelligent diagnosis and treatment techniques in improving clinical diagnostic rate of pancreatic cancer, selecting a reasonable treatment regimen, and improving the effect of surgical treatment. [ABSTRACT FROM AUTHOR]

Copyright of Hydrographic Surveying & Charting / Haiyang Cehui is the property of Hydrographic Surveying & Charting Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND: Scaphoid fracture is commonly seen in wrist fracture, but its nonunion rate is high. Therefore, studying trajectory of normal scaphoid bone is of great significance for selecting optimal fixation way and position. OBJECTIVE: To study the trajectory of normal scaphoid bone, and to provide method for three-dimensional kinematics analysis. METHODS: Twenty normal adults (n=10 in either sexes) were enrolled, and the right wrist underwent spiral CT scan in neutral, palmar flexion, dorsiflexion at 15, 30, 45 and 60 degrees, radial deviation at 10 and 20 degrees and ulnar deviation at 15 and 30 degrees, respectively. The original DICOM data were imported into Materialise Mimics Innovation Suite 15.0 to reconstruct distal radius and scaphoideum, and three-dimensional registration. The centroid of each bone was measured, and trajectory of scaphoideum was reconstructed to calculate the displacement value. RESULTS AND CONCLUSION: In palmar flexion and dorsiflexion or radial/ulnar deviation, the distance between centroid of scaphoideum and distal radius was different. In the 60 degrees of dorsiflexion and 30 degrees of ulnar deviation, the displacement was largest. In the 30 degrees of dorsiflexion and 20 degrees of radial deviation, the displacement was smallest. The displacement value in different positions showed significant differences between sexes. In summary, the accurate determination of the centroid of scaphoid bone provides a new scientific method for the reconstruction of scaphoid movement. [ABSTRACT FROM AUTHOR]

BACKGROUND: For severe rigid kyphoscoliosis patients, due to severe spinal deformity, and high risk for orthopedic surgery, designing an individualized and precise placement and osteotomy scheme preoperatively is needed to reduce surgery risk. OBJECTIVE: To evaluate the clinical effect of three-dimensional (3D) printing applied in the orthopedic surgery for severe rigid kyphoscoliosis. METHODS: Thirty-two patients with severe rigid kyphoscoliosis from January 2015 to June 2017 were included. Sixteen cases underwent 3D-assisted osteotomy (preoperative spinal reconstruction by 3D printing, and designing rational osteotomy scheme, trial group), and other 16 cases received orthopedic surgery under X-ray (control group). The perioperative indexes, postoperative correction effect, accuracy of pedicle screw placement and incidence of complications were recorded. RESULTS AND CONCLUSION: The operation time, intraoperative blood loss, intraoperative fluoroscopy time, postoperative drainage, postoperative incidence of complications, postoperative scoliosis and kyphosis Cobb angle in the trial group were significantly lower than those in the control group, but the accuracy of pedicle screw placement, scoliosis and kyphosis corrective rate were significantly higher than those in the control group (P < 0.05). To conclude, based on 3D printing, an individualized and precise placement and osteotomy scheme is designed for severe rigid kyphoscoliosis, can improve the operation safety, reduce the trauma, and obtain satisfactory clinical outcomes. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Clinical Healthcare is the property of Chinese Journal of Clinical Healthcare and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Shenzhen University Humanities & Social Sciences is the property of Journal of Shenzhen University (Humanities & Social Sciences) Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective: To evaluate the clinical value of real-time three-dimensional transthoracic echocardiography for detecting the left atrium (LA) function in mitral valvuloplasty (MVR). Methods: The maximum volume of LA(LAVmax), minimum volume(LAVmin), systolic volume(LAVp) and ejection fraction(LAEF), passive ejection fraction(LAPEF) and active ejection fraction(LAAEF) of 87 cases of patients with mitral regurgitation (case group) were examined by real time three-dimensional transthoracic echocardiography respec­tively before and at 1 week and 24 weeks after MVR, and compared with 80 healthy volunteers in the same period. Results: The preoper­ative LAVmaxI, LAVminI, LAVpI, LAEF, LAPEF and LAAEF values between the case group and the control group were statistically signifi­cant (P<0.05), the LAVmaxI, LAVminI, LAVpI, LAEF and LAPEF values from MVR lw to 24w were continuously improvement (P<0.05), while the LAPEF values showed no obvious change (P>0.05). At 24 weeks postoperation, the proportion of severe LA dilatation de­creased from 58.6 % to 12.6 %, and LA remodeling was found 67.8 % cases. Conclusions: Real time three-dimensional transthoracic ech­ocardiography showed LA volume and functional improvement after MVR, which was of some value in evaluating the curative effect of MVR. [ABSTRACT FROM AUTHOR]

Objective To study body 3D posture sensing detection method to facilitate human behavior analysis, motion recognition and etc in the industries of medicine, art and so on. Methods The body was divided into 18 inter-related vectors by establishing 3D spatial coordinates and selecting adjacentjoints as the starting and ending points. Three-axis magnetic sensor and three -axis acceleration sensor were combined to measure the directions of the vectors, and the sensor attitude angles were calculated to reflect the vector directions. The vectors had the sizes measured by a ruler. A body 3D spatial space was defined, and the projections to the body 3D spatial coordinate plane were computed for the vectors, and then the coordinates of thejoints associated with the vectors were obtained in the body 3D space to determine the body 3D postures. Results Body 3D posture sensing detection algorithm proved its feasibility by installing limb vector direction sensor on the mannequin. Conclusion Body 3D posture sensing detection algorithm can be applied to medical diagnosis, motion data acquisition, animation and etc. [ABSTRACT FROM AUTHOR]

Copyright of Natural Gas & Oil is the property of Editorial Department of Natural Gas & Oil and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective To evaluate the reproducibility of three-dimensional high-resolution magnetic resonance imaging (HR-MRI) for vessel wall in demonstration of intracranial atherosclerotic plaque enhancement and to explore the relationship between plaque enhancement and ischemic stroke. Methods Fifty-two patients with ischemic stroke underwent traditional head MRI, three-dimensionaltime of flight magnetic resonance angiography and HR-MRI on a 3.0T MRI scanner.Each identified intracranial plaque was classified as either culprit (the only or most stenotic lesion upstream from a stroke) or non-culprit (not the most stenotic lesion upstream from a stroke or not within the vascular territory of a stroke). The degree of plaque enhancement was graded by two independent radiologists. The degree of plaque enhancement and luminal stenosis were compared between the culprit group and the non-culprit group by using Mann-Whitney U test.Binary logistic regression analysis was performed to assess the relation between the degree of plaque enhancement and culprit plaques. Results Total 118 plaques were identified in 52 patients with ischemic stroke (52 culprit plaques and 66 non-culprit plaques). The degree of enhancement was rated as strong, moderate and none in 40, 9 and 3 culprit plaques, and in 4, 24 and 38 non-culprit plaques. Both intra-observer and inter-observer agreement were high for identification of plaque enhancement (kappa＞0.75). For culprit plaques group, the degree of plaque enhancement(Z=-7.787, P<0.01) and luminal stenosis (Z=-5.327, P<0.01) were significantly higher than those in the non-culprit group.Binary logistic regression analysis revealed that strong enhancement of plaques was independently associated with culprit plaques (OR:74.3, 95%CI:15.0-367.1, P<0.01). Conclusions Three-dimensional HR-MRI detects enhancement of intracranial plaques with high reproducibility.Enhancement is more common in culprit plaques and is associated with the likelihood of ischemic stroke. [ABSTRACT FROM AUTHOR]

BACKGROUND: The spine structural unit of the cervical spine is a common site of degeneration and trauma. Establishing a good cervical spine model is of great practical significance for studying the biomechanical changes of cervical vertebrae under various conditions, preventing and treating cervical injuries, and improving the treatment methods of neck and effects. OBJECTIVE: To establish a three-dimension finite element model of the whole cervical spine (C0-T1) in normal human and provide a good experimental application basis for further biomechanical research. METHODS: A healthy adult volunteer was selected as the object for data collection. The original data obtained by 256-row CT thin layer scanning, which then has been extracted and edited by software to implement reverse reconstruction. The three-dimensional finite element model of whole cervical spine (C0-T1) was established by the numerical simulation. The range of motion at various directions and mechanical characteristics were verified. RESULTS AND CONCLUSION: The model had 208 631 nodes and 660 876 solid elements. The range of motion in all directions was good. In addition to the larger C0-T1 mobility, all the rest of the segmental motions were consistent with previous literatures. The geometric and biomechanics characters of three-dimensional finite element model of the whole cervical spine (C0-T1) were highly similar to the intact one. The validation of the model was positive. [ABSTRACT FROM AUTHOR]

Objective To investigate the relationship between fragmented QRS (fQRS) complex and the early left ventricular remodeling or heart function in patients with acute myocardial infarction (AMI). Methods A total of 76 patients with AMI hospitalized in CCU of the Second Hospital of Tianjin Medical University were enrolled in the study. Patients were divided into fQRS group (n=29) and non-fQRS group (n=47). The clinical data including ECG, laboratory indicators, coronary angiography results and real-time three-dimensional (RT-3D) echocardiography parameter were collected in two groups. The relationship between fQRS and baseline data, fQRS and RT-3D echocardiography parameter were analyzed. At the same time, the influencing factors of left ventricular remodeling and heart function were discussed in the study. Results Compared with non-fQRS group, left ventricular end-diastolic volume (LVEDV) and left ventricular end-systolic volume (LVESV) were significantly higher, and left ventricular ejection fraction (LVEF) was significantly lower in fQRS group (P＜ 0.05). Several three-dimensional parameters including Tmsv16-SD (%) and Tmsv 16-Dif (%) were significantly higher in fQRS group than those in non-fQRS group (P＜0.05). There were no significant differences in Tmsv 16-SD (ms), Tmsv 12- SD (ms), Tmsv 12-SD (%), Tmsv 6-SD (ms), Tmsv 6-SD (%), Tmsv 16-Dif (ms), Tmsv 12-Dif (ms), Tmsv 12-Dif (%), Tmsv 6-Dif (ms) and Tmsv 6-Dif (%) between two groups. Logistic regression analysis showed that fQRS and Gensini scores had effects on heart function. At the same time, fQRS was an independent predictor for left ventricular remodeling. Conclusion Left ventricular remodeling is more obvious in patients with acute myocardial infarction complicated with fQRS, and fQRS can predict left ventricular remodeling better. [ABSTRACT FROM AUTHOR]

BACKGROUND: Acetabular defect is one of the typical characteristics of adult developmental dysplasia of the hip. The acetabular defect caused an insufficient coverage to the femoral head, which means the contact area between them decreased and the pressure increased. Stress concentration could quicken hip wear and lead to arthritis or dislocation of the hip. Till now, there is no accepted objective criterion about what degree defect could lead to biomechanics changes in the hip. OBJECTIVE: To analyze the influence of different degrees of acetabular defect on the stress distribution of hip joint by using three-dimensional finite element method, and provide theoretical guidance for clinical treatment of hip dysplasia. METHODS: CT thin layer scanning data of normal adult hip were selected. Hip dysplasia models with varying degrees of bone defect were built by using Mimics15.0 and Hypermesh software. Von Mises stress distribution on the subchondral bone of the hip was analyzed by using Ansys10.0 software in the case of single foot touchdown. RESULTS AND CONCLUSION: Each model result was consistent with the actual situation. The maximum Von Mises stress value appeared at the top of the acetabulum dome and medial posterior femoral neck. When simulating one leg standing, the smaller the CE angle, the greater the maximum Von Mises stress on femoral head was; and acetabulum increased from 2.768 MPa and 3.029 MPa with 30° CE angle to 11.075 MPa and 15.322 MPa with 5° CE angle. This change was more obvious when CE angle was less than 15°. These findings confirmed that acetabular defect increases the peak stress of the hip joint, and the greater the defect, the greater the stress was. It is suggested that clinical intervention should be done as early as possible in patients with acetabular defect. [ABSTRACT FROM AUTHOR]

In this paper, we presents a method for modeling and visualization of crop leaves based on agronomic parameters in order to improve the production efficiency of three dimensional digital media for agricultural subjects. The field experiments were conducted in the experiment farm of Beijing Academy of Agricultural and Forestry Sciences, Beijing City. During maize growth periods of jointing stage, horn mouth stage, florescence stage, grouting stage, maturation period and senility period, SPAD values of maize leaves were obtained by using SPAD-502 and four appearance parameters were collected by an apparent image acquisition system using linear light source. The four appearance parameters were diffuse reflectance, transparency, specular reflectance and roughness. In order to finely model the maize leaf appearance, leaf surface was divided into three structures including mesophyll, main vein and secondary vein. With the data, we analyzed the relationship between SPAD, growth period parameters and various kinds of appearance parameters of the three structures, respectively. We applied a variety of mathematical models to fit the data to describe the potential relationship between SPAD, growth period and diffuse, transparency appearance of mesophyll. Based on R2 and RMSE, we selected quadratic function for diffuse reflectance and negative exponential function for transparency. The coefficients of determination for the RGB channels of final diffuse model of mesophyll were 0.9137, 0.8511, and 0.6146, respectively, and their corresponding values of RMSE were 0.01549, 0.0128, and 0.01533. The coefficients of determination for the transparency model were 0.9975, 0.9913, and 0.9907, respectively, and their corresponding values of RMSE were 0.0064, 0.0096, and 0.0207. Data showed diffuse reflection and transparency of secondary vein could be classified into four sections by SPAD values and there was little difference between each class of appearance values. We used mean values of each section as diffuse and transparency parameters. The diffuse reflection and transparency of main vein has little change in whole growth periods. As such, we used mean values as unique and invariant apparent feature in diffuse and transmission reflection. We found that specular reflectance and roughness parameters of the three structures were not related to SPAD and growth period, therefore, mean values of these two appearance parameters obtained from all samples were used as a glossy appearance. Based on the above analysis, a series of quantitative appearance models for three structures were established respectively with SPAD and growth period as input parameters, and appearance material parameters as output. The spatial-varying appearance of leaf surface formed specific texture patterns. We abstracted the texture pattern and constructed a parameterized structure method to generate a structure texture image for synthesis of the geometric features of mesophyll, main vein and secondary vein structures. Each pixel of structure texture image represented a structure category of the point at this position, and we used the appearance models of each structure to assign appearance parameters for each pixel. Finally, four appearance textures were generated for simulating the appearance patterns of the leaf surface including diffuse texture, transparency texture, specular texture and roughness texture. A real-time rendering framework was developed to simulate the subtle interaction between plant leaves and light. In order to achieve a WYSIWYG display result, we simplified the light computing by decomposing light environment into a directional light source (sun) and some environment light sources (sky). A complete realistic effect was finally developed by combing the appearance model and illumination computation using a deferred lighting rendering framework which can simulate real-time shadows, ambient occlusion, and dynamic radiance from sun and sky. The experimental results demonstrated that the proposed approach was capable of generating different appearance of crop leaves by controlling the agronomic parameters and achieving a visually satisfactory display result. Our method showed diffuse reflectance and transmittance were the most affected by the parameters of SPAD and growth stage, while the specular reflection and roughness parameters were always stable. There were differences in the fitting results of diffuse and transparency model of mesophyll in RGB channels, while simulation result indicated there was little impact on the final visualization effect. Our method has a great potential to become an effective visualization tool for agricultural application, such as crop model, agricultural education system, and digital media for agricultural subjects. [ABSTRACT FROM AUTHOR]

Air-assisted orchard sprayers are characterized by a strong airflow that carries the pesticide droplets to the target canopy and assists the plant parts to move so as to allow the whole tree penetrated with pesticide droplets. The airflow distribution and movement characteristics are key parameters of sprayer for droplet deposition on target canopy. In order to study the 3D (three-dimensional) spatial distribution of airflow field from an air-assisted orchard sprayer, this article used ICEM CFD (Integrated Computer Engineering and Manufacturing code for Computational Fluid Dynamics) to establish a geometric model, whose whole structure was meshed, and the k-ε turbulence model and CFX solver were adopted. The effect of different environmental systems on airflow 3D distribution for air-assisted orchard sprayer was estimated, in which the upper deflector angle was set as 30°, 45°, 60°, and 90°, and the lower deflector angle was set as 0°, 10°, 20° and 30°, respectively. Results show that the 3D spatial distribution model of the airflow from air-assisted orchard sprayer can reflect the airflow distribution directly, and the simulated values of airflow characteristic curve are in good agreement with the measured values. However, in the low airflow velocity region (the velocity below 2 m/s), the simulated velocity values of some sampling points are quite different from measurements. That is caused by the perturbation of the natural wind. In the high airflow velocity region with 1.2 m width, the average relative error between the measured value and the simulated value of wind speed is less than 10%. That can confirm that the simulation results are credible. Meanwhile, airflow guided by deflectors is mainly focused in the area the deflectors pointed to, with no obvious effect on airflow diffusion in the middle area, only increasing the airflow velocity and letting airflow gather near deflector area. So the adjustment of deflector angle should be based on the height of canopy and tree trunk, through setting lower deflector angle to fit the foliage limit of the orchard, and setting upper deflector angle to point at position which is little lower than the topmost of tree canopy in the orchard. For further research, to change airflow velocity of the fan has no significant effect on airflow distribution in the airflow field, and merely increases airflow diffusion region. When the lower deflector angle increases from 0° to 30°, the effect of ground friction resistance on the airflow decreases gradually, and the angle between ground friction resistance and air resistance on both sides increases constantly, so one single air current is divided into 3 air currents gradually. This kind of air distribution on horizontal plane has advantages on blowing branches and leaves and penetrating droplets into fruit tree canopy. The airflow velocity distribution in the vertical direction considerably affects the distribution of spray droplets in canopy. The vertical profile of the airflow velocity should be even along the whole vegetation wall, and matched with the canopy shape curve. But the deflector can only adjust the upper and lower airflow, some deflectors are suggested to be fixed in the middle area for adjusting airflow distribution in vertical direction. This study found that a better effect could be achieved by setting the upper and lower deflectors angle as 30° for spraying in the Chinese general orchard where fruit trees had 3.0-3.2 m height and were planted with 4 m row spacing, and by setting the upper deflector angle of 90° (or removing), and the lower deflector angle of 30° for spraying in trellised orchard. The results can provide the reference for the spraying in the orchard, and the higher spraying efficiency and the reduction of environmental pollution can be achieved through the calibration of sprayer operational parameters. [ABSTRACT FROM AUTHOR]

With the development of imaging technology, three-dimensional CT reconstruction has been widely used in hepatobiliary surgery. Three-dimensional CT reconstruction can divide and reconstruct two-dimensional images into three-dimensional images and clearly show the location of lesion and its relationship with the intrahepatic bile duct system. It has an important value in the preoperative assessment of liver volume, diagnosis and treatment decision-making process, intraoperative precise operation, and postoperative individualized management, and promotes the constant development of hepatobiliary surgery and minimally invasive technology, and therefore, it holds promise for clinical application. [ABSTRACT FROM AUTHOR]

In order to deepen the interference among the thin alternating layers of law awareness, clear heterogeneity influence on effect of water flooding, constant speed method was applied for artificial three-dimensional cementation physical model test of water flooding. Severe heterogeneity between layers is studied under the condition of all kinds of reservoir water flooding. The experimental results show that; under the condition of high permeability model, water inflow and speed were significantly greater than low permeability model, two high permeability models interfere each other if permeability is smaller, and the propulsion affected by gravity is obvious at the bottom of the injected water. It also shows closing the high permeability model can effectively improve the water flooding effect of low permeability model. Hence, we should control permeability difference, combine reasonably formation in order to improve oil recovery effect. The three-dimensional physical simulation experiments holds strong practicability, and oil field. The laws obtained have certain guiding significance. [ABSTRACT FROM AUTHOR]

Copyright of Hydrographic Surveying & Charting / Haiyang Cehui is the property of Hydrographic Surveying & Charting Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective To assess the value of high-definition flow imaging (HD-flow) as well as three-dimensional (3D)sonography (US) combined with HD-flow technique (3D-HD) in the detection of normal fetal aortic arch and the brachiocephalic arteries. Methods Sagittal US scans with 3D-HD were performed on 180 normal fetuses to evaluate the aortic arch and its branches. The 3D volume data were post-processed to obtain the volume rendered images of the aortic arch and its branches. The number of the vessels recorded by the HD-flow and the 3D-HD methods were compared. Results 3D-HD modality was best for demonstrating more vessels before 29 gestational weeks, whereas HD-flow was the best modality in later gestation. Conclusion Fetal aortic arch and the brachiocephalic arteries are well visualized on sagittal US with HD-flow. 3D US combined with HD-flow technique can generate high-definition 3D images with improved visualization of the course, branching, and spatial relationships of the great arteries. [ABSTRACT FROM AUTHOR]

In the process of discrete element numerical calculation, the establishment of the particle model is an important factor to affect the accuracy of the simulation.It is necessary to establish the 3-D models of irregular grains for discrete element method whose morphology is approximate to the real grain to analyze and simulate the main working process like precision seeding and precision selecting and classifying seeds.At present, an irregular particle with complex contours is simplified into the regular shape to model, which can lead to reduction of the simulation accuracy. In order to improve the accuracy of the dynamic simulation of the irregular particles, a method of modeling 3-D DEM models was proposed for irregular shape particles like rice grain based on 3-D laser scanning.Five hundreds of Kongyu 131 (rice cultivar) rice seeds were chosen randomly and scanned using CF-30 automatic high precision 3-D scanner.The size distribution of length, width and thickness is in accordance with the normal distribution and the average length, average width and average thickness of the three-dimensional measurement were 7.0 mm, 3.5 mm and 2.4 mm, respectively.The rice seed with the average three-dimensional sizes was scanned and the polygonal contour model and space coordinate information were obtained by the process of treating color, noise removal, point cloud registration, point cloud triangulation, consolidation and model modification using the reverse engineering software Geomagic Studio.The polygonal contour model was imported into SolidWorks and the 3-D DEM model with complex contour of the rice seed based on 3D laser scanning was created by inverse modeling.The 3-D DEM model of the rice seed based on 3D laser scanning was filled by 87 balls particles based on the theory of polymer particles, which was named as Model1.The 3-D DEM model of the rice seed with the same three-dimensional sizes as Model1 was processed usually as regular ellipsoid, which was named as Model 2.In order to test the simulation accuracy for discrete element method of the modeling method of irregular particle based on 3D laser scanning, the simulation prediction of repose angle for Model 1 and Model 2 was done respectively using the discrete element method software EDEM.The repose angle of the Model 1 and the Model 2 were 29.77° and 27.08°, respectively.And the repose angle of the actual rice seeds was measured under the same condition as the simulated experiment condition for comparative analysis.The experimental result of the repose angle was 29.70°. And the measurement errors between the simulation results by two modelling methods and the actual experiment value about repose angle were 0.24% and 8.83%, respectively.The repose angle obtained by Model 1 based on 3-D laser scanning was closer to not only the experimental measured value but also accumulation form, and there was a big error between that by Model 2 based on the usual treatment as regular ellipsoid and the experimental result, which showed that the modeling method of irregular particle for discrete element based on 3-D laser scanning was validated and available.This paper provides a new means to improve simulation precision of irregular particles for discrete element method. [ABSTRACT FROM AUTHOR]

Objective To summarize the experience in retroperitoneal living donor nephrectomy under 3D laparoscopy and to investigate its clinical effect and safety. Methods The clinical data of 19 cases who underwent retroperitoneal living donor nephrectomy under 3D laparoscopy were collected. Operation duration, intraoperative blood loss, renal warm ischemia time, length of renal artery, renal vein and ureter, incision size and operative complications were recorded. Postoperative renal function of donors and recipients was observed. Results Nineteen cases of living donor nephrectomy were successfully completed under the 3D laparoscopy, and there were no conversion into conventional laparoscopy and open surgery. The operation duration of living donor nephrectomy under 3D laparoscopy was 80.5-125.2 (with an average of 102.3)min; intraoperative blood loss was 40.6﹣90.4 (60.8)ml; renal warm ischemia time was 100-230 (161)s. Length of renal artery, renal vein and ureter was 2.6-3.2 (2.9) cm, 2.2﹣3.0 (2.6) cm and 8-13 (10) cm, respectively. The incision size was about 5-6 cm,and the wound healed. Urine volume of the donors at 24 h after operation was 2 000-2 500 ml. Serum creatinine increased slightly in 1 case at 3 d after operation, and returned to normal through reexamination after 7 d and 1 month. The donors stayed in the hospital 5-7 (6) d after operation. All transplant operations were performed successfully, and delayed graft function did not occurred. Conclusions Accuracy of operation can be improved effectively by 3D laparoscopic surgery system.It is safe and feasible to perform retroperitoneal living donor nephrectomy under 3D laparoscopy. [ABSTRACT FROM AUTHOR]

The characteristics of fracture roughness of sandstone under shear loading were specifically discussed through the fracture surface scanning visual map, contour map of the distribution of the fracture surface and the fracture surface profile contour, according to the 3 D information of fracture roughness of sandstone under shear loading collected by self-developed coal or rock shear-flow coupling test device and 3D scanners. It is showed that the deformation characteristic curves generally were in good agreement, the visual features of fracture surface were different from each other, and the distribution of roughness heights was appromiately accorded with normal distribution. Characteristics of profile along the shear direction and perpendicular to the shear direction are different, and cannot reflect the whole fracture surface features. The analysis of roughness parameters relationship among RL, RS and JRC suggests that there was a linear correlation between JRC and RL ,and the linearity of RS and the average value of JRC was better than that of JRC and RL. So the average value of JRC is more suitable to reflect the 3D characteristics of fracture surface. [ABSTRACT FROM AUTHOR]

Phenotypic traits of corn ears are important parameters for maize breeding and production forecast. A phenotypic computation method based on distribution map of kernels for corn ears is presented to comprehensively analyze the geometrical, quantitative, color and texture traits of corn ear and its kernels. A phenotypic detection system of corn ears, which consists of stepping motor, charge coupled device (CCD) camera, light-emitting diode (LED) back lights, image acquisition card and semiclosed box, is designed to capture main side images of corn ear. Corn ear is fixed vertically on a turn table driven by stepping motor, and thus image sequence of corn ear can be captured from designated angles and covers the entire surface of corn ear. In this study, 4 orthotropic images are captured to build three-dimensional reference frame of corn ear. Firstly, axial and radial distortion corrections are successively applied to image sequences and generate standard image sequence of corn ear. Therein, axial distortion correction regularizes the heights of corn ear for image sequence to their average height, and radial distortion correction is used to recover size and shape of kernels on the surface of corn ear, since those kernels lie on border regions of corn ears which have obvious distortion. A dedicated image segmentation method, which has utilized geometrical and color traits of kernels of corn ear to the greatest extent, is then used to extract all kernels of corn ear from corrected image sequence. Meanwhile, contour lines and split lines of corn ear in image sequence are calculated based on pixel scale, and used to generate the mapping relationship among the images of corn ear. Contour lines of corn ear can be used to generate a three-dimensional surface model by transforming the coordinates of lines from two-dimensional to three-dimensional space, and then the three-dimensional model of corn ear is used to calculate geometrical traits, e.g.perimeter, surface and volume.Moreover, contour lines of corn ear can also output corresponding split lines which split each corn image into different regions, and further classify kernels into different types according to position relationship between kernels and split lines.On the basis of kernel scale, the classified kernels from segmented image sequence can be assembled together to generate a distribution map which describes entire surface kernels of corn ear. According to the distribution map of kernels and segmented image sequence, the quantitative and geometrical traits of kernels, such as rows per ear, kernels per row, total kernels and kernel thickness can be accurately calculated using Delaunay and BellmanFord methods.The proposed method and system can simultaneously detect multiple types of phenotypic traits from image sequence of corn ear, and have higher accuracy in almost all phenotypic traits than the detection method based on single profile image of corn ear.Experimental results demonstrate that the computed traits have good consistence with the observed values, and the average computation accuracy of main traits, i.e.rows per ear, kernels per row, total kernels, ear length and ear diameter, can respectively reach 98.231%, 94.351%, 96.921%, 98.956% and 98.165%.Thus, the proposed method can be applied for precise phenotypic detection and breeding of corn ears. [ABSTRACT FROM AUTHOR]

Copyright of Hydrographic Surveying & Charting / Haiyang Cehui is the property of Hydrographic Surveying & Charting Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Counting the total volume of grain in the granary, which represents an indispensable work in grain storage management, is of great importance to the macro grain regulation in China. In response to the low efficiency and accuracy of traditional way to survey and map the grain-pile volume in granary, this paper proposed a method for rapidly re-constructing the 3D model of the grain pile based on 3D laser scanner technique, and a method for accurately calculating the grain-pile volume based on constructing 3D laser monitoring system. This system employed the DME5000 of German SICK, the 3D laser range finder with its range finder installed on the grain pile and then created a Cartesian coordinate system in a granary. With the range finder scanning the surface of grain pile, distance can be calculated between the point on the grain pile and the bottom of the granary, and the original point cloud data of the information about the grain pile can be obtained after scanning some points. As noise point could not be avoided during the process of collecting those data because of the influence from environment and irregular point clouds were scattered, the standard point cloud data could be acquired by processing the original data through noise-eliminating, jointing and gridding. Median filter was used to remove noise while weighted average algorithm was applied in polygonizing. The standard point cloud data were processed with 3D triangulation in accordance with the Delaunay principle, on the basis of which three-dimensional curve surface model of grain piles were built. Then the 3D model of the grain pile could be built with the help of 3D rendering engine on the basis of Windows Presentation Foundation, a technology from Microsoft. At the same time the grain-pile volume could be calculated by means of square grid. The principle of the grid algorithm was to divide the bottom of the grain pile into a number of squares so that the total volume of the grain pile could be equal to the total volume of the columns with a square bottom. The system was firstly adopted in an experiment to calculate the volume of the grain pile in a laboratory which located in Beijing Forestry University. Due to the small volume of the grain pile for experiments, accurate measurement could be done manually. The actual volume of the grain pile was 2.205 m3. By completing scanning ten times and analyzing the data acquired in this experiment, we got the relative tolerance of only 0.318% between the actual volume of the grain pile and the one calculated by scanning the grain pile with this system, with the standard deviation of 0.0083m3. Another experiment was conducted in a granary in Cangzhou, Hebei province. The experimental result was compared with the one acquired by means of manually traditional surveying and mapping method. After ten times of surveying and mapping with the help of this system, we got the average grain volume of 22 469.97 m3, with the standard deviation of 42.92 m3. The volume calculated with traditional manual method was 22 466.50 m3, with the standard deviation reaching 70.25 m3. The experimental results showed that this system could acquire accurate and stable grain-pile volume, and definitely meet the requirement of granary management in real works. This provides an effective way to improve the efficiency and accuracy of accounting inventory in the management of granary in reality. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Measurement Science & Instrumentation is the property of Journal of Measurement Science & Instrumentation and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Plant leaf is an important organ for photosynthesis and transpiration, and it has a significant effect on plant growth, yield and quality of crops. It is necessary to measure the three dimensional(3D) morphology(3D coordinates of each point on the surface of plant leaves) and illuminance distribution of leaves are important for the study of plant growth. Therefore, in this paper, we proposed a method of measuring the leaf 3D morphology and illuminance distribution synchronization of texture plants based on binocular vision. Firstly, according to the pinhole imaging principle, there is a one-to-one correspondence between 3D spatial coordinate points and image points. The camera calibration is a necessary process when the recovery of information such as angles and distance of spatial points and image points is required. So the intrinsic and external parameters and distortion parameters of the camera were obtained by improved Zhang’s Calibration. For obtaining the 3D spatial coordinate points，two cameras was used to capture the left and right image by the binocular vision principle. To find out the same texture image points of leaves, the digital image correlation technique was used. From the above work we can measure 3D coordinate points of leaf and calculate distance that surface point of leaf to the left camera optical center. For improving the accuracy of 3D coordinate points measurement, the left and right raw format images of chessboard calibration target and leaf were captured by using two same type of color COMS cameras with high resolution and unpacked it to RGB 3-channel images. G channel image brightness was still highest when the illuminance was much lower, so chosen G channel image for calculation. Secondly, in order to achieve the illuminance distribution, according to the applied optics theory and lambert′s law, the image gray values and the illuminance were positively correlated. So an image illuminance measurement equation was developed. Leaf surface illuminance was only related to the distance and image gray values when the camera system parameters were invariant for diffuse reflectance plant leaves. Therefore, when the image gray values and the distance were obtained, the illuminance calculation of plant leaves can be realized. For improving the accuracy of 3D illuminance distribution measurement, converted the RGB format image to HSV format image and segmentation based on hue of image and smoothed. Thirdly, in order to verify the reliability and accuracy of the synchronous measurement method, in this paper, we took Fittonia arundinacea as experiment object. We needed to calibrate before experiment. So 16 left and right chessboard calibration target images under the different postures were captured and used to calculate the intrinsic, external parameters and distortion parameters, and irradiated it with uniform light. One hundred leaf left and right images and the corresponding illuminance data were collected synchronously, then the size of 30×20 pixels of leaf area were selected to calibrate the camera system parameters. For verifying the illuminance equation, captured 120 left and right images of different light intensity and measured illuminance，the illuminance sensor was used to measure the corresponding illuminance. Through the comparative analysis of the illuminance sensor measurement values and the image measurement average values, we found that the correlation was 0.996, the average relative error was less than 6%, which can meet the basic requirements of the application of agricultural information monitoring in intelligent light control. Besides that, it was irradiated with non-uniform light and the image was collected. The original G channel image for 3D morphology measurement was used. The results showed that it was the best when the sub region radius was 57 pixels and the interval of sub region was seven pixels. The illuminance equation was used to measure illuminance distribution of the original G channel image and the hue segmentation and smooth G channel image of leaf synchronously, the latter was better. The experimental results showed that the method can satisfy the synchronous measurement of 3D morphology and illuminance distribution of the leaf. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) Plant modeling and visualization is a key research issue in both digital plant and agricultural application. Leaf is one of the vital organs in a plant, so the 3D modeling and shading of plant leaves is an important and fundamental work for achieving the goals of digital plant. Appearance simulation of plant leaves is still a challenging issue because of its intricate underlying structure and complex and subtle interaction with light. Texture mapping using leaf photo is a common method for appearance simulation, however, it could bring noise caused by light environment and camera position in lighting simulation step. This paper presents a technique for simulating the appearance of plant leaves with multiple images. Our method can estimate the spatially-varying reflectance properties of plant leaf surface based on a few images, which capture leaves' appearance transition information with different light directions. An apparent image acquisition system using linear light source is built for capturing 400 images with a fixed camera viewpoint and a single direction of motion for the linear light source. This system is composed of a driving module, a linear source module, a background module and a camera. Using a linear light rather than a point light source as the illuminant, we can obtain a piece of area with more intensive illumination. With these image data, we develop a fitting method, which is able to estimate the diffuse color, specular color and specular roughness of each point on the leaf surface. In our method, the isotropic ward model is utilized as the appearance model for specifying that how the leaf surface reflects light. Our fitting technique first simulates the change of reflectance attributes of diffuse and specular reflectance lobes under moving linear light source. In this process, a rectangle is employed to simulate the linear light source and Monte Carlo integration method is used to calculate the radiation transmission process. When we have the simulating results, the appearance parameters of each pixel are determined by comparing its actual parameter values to the simulating results. By above fitting method, 3 kinds of spatially-varying appearance parameters are saved into 3 parameter images for rendering leaf appearance. For quickly shading, multipoint point light sources are used for simulating various illumination conditions instead of complex radiative transfer integral. Using appearance parameter images and shading method, static appearance or dynamic appearance transition of plant leaves can be generated realistically. From the results obtained by this method, we find that it can render more accurate and real appearance texture of leaves compared to traditional texture mapping methods. The advantages of our method are that the appearance parameter images for rendering have removed the light and viewport noise, and only contained the appearance material information. In order to prove this conclusion, we quantitatively analyze the reason for this advantage by some formula derivations in this paper. But for obtaining these advantages, our method needs more complex data acquisition process and parameter fitting algorithm, which will reduce the efficiency of simulation. For improving the efficiency of our method, 2 approaches are discussed in this paper, including reducing image resolution and fitting the specular parameters of the whole leaf by a few sample points. Our method can estimate some appearance parameters which are plant leaf own intrinsic properties. We believe this characteristic will make these appearance parameters used not only for visualization, but also as some important phenotypes instead of so-called color data. In the future work, we will extend the application of our method in agriculture, such as monitoring plant growth status with the appearance parameters, or analyzing the differences among plant varieties. [ABSTRACT FROM AUTHOR]

Objective The aim of this study is to evaluate the shrinkage mode of the primary tumor in women with breast cancer after neoadjuvant chemotherapy (NAC) determined by part-mount sub-serial section (PMSS) and three-dimensional (3D) reconstruction technique. Methods Eighty-six women with pathologically proven solitary invasive ductal carcinoma (ⅡA-ⅢC) were recruited. They were divided into two groups. Group A (n=25) received half cycles of NAC and Group B (n=61) received whole cycles of NAC. Breast specimen was prepared with PMSS, and residual tumors were microscopically outlined, scanned and registered by Photoshop software. The 3D model of residual tumors was reconstructed with 3D-Doctor software to evaluate the shrinkage mode. Further, the clinicpathologic shrinkage modes were divided into 2 categories: concentric shrinkage mode (CSM, the longest diameter of the pathological residual tumors was less than 50% and ≤2 cm in comparison with the primary tumor before NAC), and non-concentric shrinkage mode (NCSM, the longest diameter of the pathological residual tumors was more than 50% and/or >2 cm in comparison with the primary tumor before NAC). Results Pathological shrinkage modes: Group A: modes Ⅰ, Ⅱ, and Ⅴ were observed in 1, 1, and 23 cases, respectively; Group B: modesⅠ, Ⅱ, Ⅲ, Ⅳ, and Ⅴwere observed in 18, 3, 12, 21, and 7 cases, respectively (P<0.001). The multivariate analysis showed that patients with lower primary tumor stage, PR(-) or mammographic malignant calcification before NAC(-) and lymph nodes down-staging after NAC were more likely to present with CSM after NAC (P<0.05 for all). Conclusions The pathologic reconstruction of breast residual tumors can fully and three-dimensionally reveal the shrinkage mode of the primary breast tumor in women with breast cancer after NAC. PMSS and 3D reconstruction of pathology provide a new platform in this area. Primary tumor stage, PR expression and mammographic malignant calcification before NAC and lymph node down-staging after NAC are independent predictors of the clinicopathologic shrinkage mode. [ABSTRACT FROM AUTHOR]

Birds are propelled and lifted by wings，flapping and rotating motioa In this study, the rotation amplitude and rotation time interval of wings were studied, the self-propelled flying motion of a threedimentionaK3D) bionic bird in a viscous flow is investigated numerically with a 3D computational fluid dynamics (CFD) package. The package includes the immersed boundary method (IBM), the volume of fluid (VOF) method, the adaptive multi-grid finite volume method, and the swimming and flying control strategy. It is suggested that the bird can fly faster forward or upward with an appropriate rotation amplitude and rotation time interval. [ABSTRACT FROM AUTHOR]

Objective: To assess three-dimensional echocardiographic application value of different ages and gender on bicuspid aortic valve malformation (BAV). Methods: Echocardiography in our hospital from June 2012 to September 2014 detected 70 cases of BAV patients, which were divided into 4 groups according to the age, ≤20 age group 7 cases, 21-40 age group 14 cases, 41-60 age group 30 cases, and ≥60 age group 19 cases; which were divided into 2 groups, 42 cases in male, 28 cases in female according to the gender. Measurement of different cases on internal diameter and of Aortic sinus and ascending aorta, interventricular septum thickness, left ventricular function and left atrial diameter, four complication rates were compared with aortic stenosis, regurgitation, calcification and prolapse. Results: In cardiac structure, age groups on interventricular septal thickness in ≥60 age group 12.37±1.64 mm is higher than ≤20 age group 10.43±2.22 mm and 21-40 age group 11.00±1.92 mm; left atrial diameter in 41-60 age group 38.73±7.95 mm and ≥60 age group 40.05±9.71 mm are higher than ≤20 age group 29.86±1.86 mm. Gender groups on left ventricular function in female 64.18±6.04% is greater than male 58.71±11.28%. In complication rates, age groups on aortic stenosis in 41-60 age group 80%, ≥60 age group 84% are higher than 21-40 age group 50%, gender groups on stenosis in male 81% is greater than female 54%, regurgitation in female 79% is greater than male 50%. Conclusion: Three dimensional echocardiography in the diagnosis of BAV can obtain more comprehensive and specific, intuitive diagnostic information, ultrasonography in patients with BAV is closely related to the age and gender. [ABSTRACT FROM AUTHOR]

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目的探讨腰椎计算机断层扫描（CT）三维成像在低辐射剂量迭代技术中的临床应用价值。方法随机选 取186 例可疑病变患者进行腰椎CT 扫描，分常规剂量组和低剂量组，每组各93 例，比较两组辐射剂量和影像质量评 分。结果低剂量组容积CT 剂量指数、剂量长度乘积和平均有效剂量低于常规剂量组，降低率分别为70.15%、65.01% 和65.03% ，差异有统计学意义（P<0.01）。两组腰椎CT 影像噪声平均值和腰椎CT 影像质量显示能力评分比较，差异无 统计学意义（P>0.05）。结论在腰椎CT 三维成像中应用低剂量迭代技术，不仅降低了辐射剂量，而且保证了影像质 量，具有较好的临床应用价值。 [ABSTRACT FROM AUTHOR]

Pelvic floor dysfunction is a common disease in elder women. The incidence increases year by year,it has a serious impact on the health and quality of life in elder women. With the development of medical imaging technology and computer technology, the finite element analysis of pelvic biomechanics becomes the hot spot in the study of pelvic floor dysfunction. At present,the finite element analysis has already been widely used in orthopedics, however, because of the complex anatomy of pelvic floor, and the difficulty of building a model accurately, the domestic research on the finite element of pelvic floor is still in its infancy. The establishment of the finite element model of pelvic floor and the mechanical analysis, not only can help the gynecologist to understand the mechanism of pelvic floor dysfunction, but also can help them to make the optimal surgical plan and to predict the efficacy of the treatment. With the continuous improvement of medical imaging technology and computer hardware, we believe that the application of finite element analysis method will play an important role in the gynecology. [ABSTRACT FROM AUTHOR]

Objective To investigate the efficacy of the three-dimensional multiple echo recalled gradient-echo (3D MERGE) sequence in MR imaging of lumbosacral plexus. Methods 31 patients with lumbosacral vertebral lesions underwent MRI including 3D MERGE and STIR sequences..The source images were post-processed by using maximum intensity projection. (MIP) on the workstation. The image quality of lumbosacral plexus, the signal to noise ratio (SNR) and contrast to noise ratio (CNR) of both sequences were compared. Results 3D MERGE was significantly superior to STIR sequence for visualizing the lumbosacral plexus anatomy with higher SNR and CNR (P<0.05). The scan time of 3D MERGE was shorter than that of STIR sequence. Conclusion 3D MERGE sequence can clearly display the lumbosacral plexus and is clinically useful. [ABSTRACT FROM AUTHOR]

Objective To conduct the modelling of femoral calcar defected intertrochanteric facture by using the three-dimensional finite element technology, to analyze the biomechanical characteristics of rebuilding femoral calcar by using the bone cement reconstruction and restoration of fracture fragments in hip replacement, and to analyze the stability of two kinds of recon struction method. Methods The fracture model of femoral calcar defected intertrochanteric facture (Evans-Jeason typeⅣideal model) was established. The femoral calcar was reconstructed by using the bone cement reconstruction and restoration reconstruc-tion of fracture fragments in hip replacement. The three-dimensional finite element method was used to simulate and analyze the biomechanical stability of the two kinds of femoral calcar reconstruction at the feet standing position and under normal load. Re-sults After mechanical loading, compared with the femoral calcar fracture restoration, the maximum stress value and maximum displacement value in the femoral calcar reconstruction model by bone cement were smaller than those in the femoral calcar re-construction model by femoral calcar fracture reduction, the stress values were 0.635,0.641 MPa, the displacement values were 0.028 74,0.028 91 m, respectively. The stress values and displacement values at 5 same points were selected from each model for conducting t test analysis. The stress values and displacement values had statistical differences between these two models of athroplasty(P<0.05). Conclusion Two kinds of femoral calcar reconstruction mode have differences in the aspects of stress intensity, stress distribution and athroplasty displacement, the bone cement reconstruction mode is superior to the femoral calcar fracture reduction mode in the aspects of uniformity of stress distribution, stress intensity and initial micromotion. Adopting bone cement for directly reconstructing humeral calcar in the bone cement hip replacement of femoral calcar defected intertrochanteric facture has better biomechanical stability. [ABSTRACT FROM AUTHOR]