Orthopedic Surgery Planning Based on the Integration of Reverse Engineering and Rapid Prototyping

This paper describes orthopedic surgical planning based on the integration of RE and RP. Using symmetrical characteristics of the human body, CAD data of the original bone without damages for the injured extent are generated from a mirror transformation of undamaged bone data for the uninjured extent. The physical model before the injury is manufactured from RP apparatus. Surgical planning, such as the selection of the proper implant, pre-forming of the implant, decision of fixation positions and incision sizes, etc., is determined by a physical simulation using the physical model. In order to examine the applicability and efficiency of surgical planning technology for orthopedics, various case studies, such as a proximal tibia plateau fracture, a distal tibia comminuted fracture and an iliac wing fracture of pelvis, are carried out. As a result of the examination, it has been shown that the orthopedic surgical planning based on the integration of RE and RP is an efficient surgical tool.Mechanical Engineerin

The Next 1616 Higher Spin Currents and Three-Point Functions in the Large N=4{\cal N}=4 Holography

By using the known operator product expansions (OPEs) between the lowest $16$ higher spin currents of spins $(1, \frac{3}{2}, \frac{3}{2}, \frac{3}{2}, \frac{3}{2}, 2,2,2,2,2,2, \frac{5}{2}, \frac{5}{2}, \frac{5}{2}, \frac{5}{2}, 3)$ in an extension of the large ${\cal N}=4$ linear superconformal algebra, one determines the OPEs between the lowest $16$ higher spin currents in an extension of the large ${\cal N}=4$ nonlinear superconformal algebra for generic $N$ and $k$. The Wolf space coset contains the group $G =SU(N+2)$ and the affine Kac-Moody spin $1$ current has the level $k$. The next $16$ higher spin currents of spins $(2,\frac{5}{2}, \frac{5}{2}, \frac{5}{2}, \frac{5}{2}, 3,3,3,3,3,3, \frac{7}{2}, \frac{7}{2}, \frac{7}{2}, \frac{7}{2},4)$ arise in the above OPEs. The most general lowest higher spin $2$ current in this multiplet can be determined in terms of affine Kac-Moody spin $\frac{1}{2}, 1$ currents. By careful analysis of the zero mode (higher spin) eigenvalue equations, the three-point functions of bosonic higher spin $2, 3, 4$ currents with two scalars are obtained for finite $N$ and $k$. Furthermore, we also analyze the three-point functions of bosonic higher spin $2, 3, 4$ currents in the extension of the large ${\cal N}=4$ linear superconformal algebra. It turns out that the three-point functions of higher spin $2,3$ currents in the two cases are equal to each other at finite $N$ and $k$. Under the large $(N,k)$ 't Hooft limit, the two descriptions for the three-point functions of higher spin $4$ current coincide with each other. The higher spin extension of $SO(4)$ Knizhnik Bershadsky algebra is described.Comment: 94 pages; The 43 and 44 pages added, the mathematica notebook files included and to appear epj

Estimation of Appropriate Process Parameters for a Plasma Electron Beam Re-Melting Process Using Finite Element Analysis

Metal additive manufacturing using electron beam melting (EBM) process applies electron beam for heating, sintering, and melting of powders to fabricate a three-dimensional component. The component may contain residual porosity internally and may be subjected to poor surface finish externally. To improve the quality of the surface finish and densification, re-melting is conducted. The purpose of this paper was to estimate the appropriate process conditions for a plasma electron beam remelting process using heat transfer finite element analyses (FEAs). The impact of the travel speed of table and thickness of the deposited part on temperature distributions were examined. The size of molten pool was estimated from the results of the thermal FEA. From the estimated size of molten pool, the travel speed of table and the hatch spacing between remelting tracks are discussed and selected as the appropriate process conditions for electron beam re-melting process from the perspective of minimum overlapping region of the molten pool

Characteristics and Trends of Strawberry Cultivars throughout the Cultivation Season in a Greenhouse

Each strawberry (Fragaria × ananassa) cultivar has its own growth and yield characteristics. However, the characteristics of many cultivars have not been determined at a consistent time and place, making direct comparative analysis difficult. The objective of this study was to identify characteristics and trends of five Korean strawberry cultivars in the same environment during an entire season. Therefore, environmental factors such as daily average air temperature, daily average relative humidity, daily average solar radiation, daily soil temperature, daily soil water content, daily soil electrical conductivity (EC), plant growth characteristics such as the number of leaves, plant height, leaf length, leaf width, and crown diameter, and productivity characteristics such as flowering and fruiting were measured to investigate the possible correlations of the data over one season. The vegetative growth of “Seolhyang” and “Keumsil” was greater than that of “Jukhyang” and “Maehyang”. The yield of “Arihyang” was greater than that of all other cultivars. “Arihyang” also presented the greatest weight per number of fruits. Among environmental factors, higher variability in air temperature and soil water content was correlated to lower total fresh weight in the following week at different degrees for each cultivar. Among the cultivars, the time to the first flowering was delayed by about seven days when the number of leaves increased by one and was reduced by one day per 1 cm increase in plant height. The total fresh weight was enhanced up to 271 g per experimental unit, while the average number of leaves increased by one. The results indicate that the data can be used by those who need information regarding the characteristics of the strawberry cultivars through direct comparative analysis

Early Outcome of Posterior Cervical Endoscopic Discectomy: An Alternative Treatment Choice for Physically/Socially Active Patients

Anterior cervical discectomy and fusion (ACDF) is currently the standard treatment for cervical disc disease. Some patients wish to be treated with a less invasive method, because of their social/physical situations. Here we present one method of treatments for socially/physically active patients. Three patients had triceps weakness and mild posterior neck pain. The offending lesions were at the C6-7 level. All were middle-aged soldiers with families. If conventional ACDF were performed, they would have to retire from the military according to the regulation. They had to be able to perform military drills after the treatment if they were going to be able to keep their jobs. Because of their social/physical situations, all wanted to choose method with that they could treat the disease and keep their jobs. For these reasons, the posterior cervical endoscopic discectomies were performed. Ruptured fragments were successfully removed in all. The arm pain improved by more than 90% in two patients by 7 days and in the other patient by 2 months, respectively (excellent outcome by Macnab's criteria). None of the operations caused instability. All of the patients are currently able to successfully perform their military drills without difficulty. The posterior cervical endoscopic discectomy may be a promising alternative for the physically/socially active patients

Corticospinal Tract Compression by Hematoma in a Patient with Intracerebral Hemorrhage: A Diffusion Tensor Tractography and Functional MRI Study

The purpose of this study was to demonstrate corticospinal tract compression that was due to a hematoma by using diffusion tensor tractography (DTT) and functional MRI (fMRI) in a patient with an intracerebral hemorrhage (ICH). A 23-year-old right-handed woman presented with severe paralysis of her right extremities at the onset of a spontaneous ICH. Over the first three days from onset, the motor function of the affected upper and lower extremities rapidly recovered to the extent that she was able to overcome applied resistance to the affected limbs, and her limbs regained normal function 3 weeks after onset. The tract of the right hemisphere originated from the primary sensori-motor cortex (SM1) and it passed through the known corticospinal tract pathway. However, the tract of the left hemisphere was similar to that of the right hemisphere except that it was displaced to the antero-medial side by the hematoma at the cerebral peduncle. Only the contralateral SM1 area centered on the precentral knob was activated during affected (right) or unaffected (left) hand movements, respectively. In conclusion, fMRI and DTT demonstrated a corticospinal tract compression due to hematoma in this patient. We conclude that the combined use of these two modalities appears to improve the accuracy of investigating the state of the corticospinal tract