• International Journal of Naval Architecture and Ocean Engineering
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• v.1 no.1
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• pp.50-56
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• 2009

The hydrodynamic effect of appendages for high-speed passenger vessels, such as Ro-Pax, Ro-Ro and cruiser vessels, is very severe and, therefore, it is essential to carry out the design of appendages for high-speed passenger vessels from the preliminary design stage to the final detail design stage through a full survey of the reference vessels together with sufficient technical investigation. Otherwise, many problems would be caused by mismatches between the appendages and the hull form. This paper investigates the design characteristics of some appendages, such as the side thruster, the shaft-strut, and the stern wedge, based on the design experience accumulated at Samsung, on CFD, and on model test results for high-speed passenger vessels. Further to this investigation, some practical and valuable design guidelines for such appendages are suggested.

• Korean Journal of Head & Neck Oncology
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• v.37 no.2
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• pp.57-60
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• 2021

Tumor of follicular infundibulum (TFI) is a rare benign cutaneous appendage tumor that does not have characteristic clinical features. It is mainly present in the head, neck, and trunk as a solitary lesion. In particular, TFI typically manifests as a plate-like proliferation with multiple thin epidermal connections comprise of monomorphic cells. TFI do not represent cutaneous characteristics, but have clinical significance because TFI is associated with basal cell carcinoma and Cowden's syndrome. We report a case of TFI in parietal scalp with a review of literatures.

• Archives of Craniofacial Surgery
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• v.23 no.2
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• pp.83-88
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• 2022

Nevus sebaceous of Jadassohn is a congenital cutaneous hamartoma with epidermal, sebaceous, follicular, and apocrine structures that usually appears at birth or in early childhood. It has the potential to generate a variety of secondary neoplasms of different lineages, and the risk increases with patient age. Although multiple neoplasms may occasionally arise within the same lesion, the coexistence of more than five secondary tumors is extremely rare. Here we report a case of seven secondary tumors including syringocystadenoma papilliferum, desmoplastic trichilemmoma, sebaceoma, trichoblastoma, pigmented trichoblastoma, sebaceous adenoma, and tumor of follicular infundibulum arising within a nevus sebaceous. The complete diagnosis relies on the histopathological analysis of multipoint biopsies and delicate pathological sections.

• Journal of the Korean Society of Marine Environment & Safety
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• v.29 no.6
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• pp.688-696
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• 2023

In the present study, free roll decay and resistance performances of fishing vessels were evaluated with the combinations and variations of in the parameters of appendages which are attached to improve motion performance of fishing vessels. Computational Ffluid Ddynamics was used to perform free roll decay and resistance analysis. The roll period and decay coefficient were derived by the variations in the combination and dimensions of the primary appendages of the bilge keel and the under keel. It was observed thatThe variations of in the length of the under keel did not significantly impact to the roll damping coefficient. Conversely, for the bilge keel, an increase in the length and angle resulted in an increase in the roll damping coefficient. Comparison of resistance performance was additionally assessed among the selected hulls with the appendages and bare hull. The resistance of the hull with the appendages was higher than that of the bare hull due owing to the changes of in the pressure on the surface of the hull and trim angle. Throughout the present study, the impact of appendage parameter and arrangement on the free roll decay and resistance performance of fishing vessels were was assessed,. which This will be beneficial for the application of appendages to fishing vessels.

• Structural Engineering and Mechanics
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• v.14 no.4
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• pp.417-434
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• 2002

This paper explores the possibility of using a combination of the empirical mode decomposition (EMD) and the Hilbert transform (HT), termed the Hilbert-Huang transform (HHT) method, to identify the modal damping ratios of the structure with closely spaced modal frequencies. The principle of the HHT method and the procedure of using the HHT method for modal damping ratio identification are briefly introduced first. The dynamic response of a two-degrees-of-freedom (2DOF) system under an impact load is then computed for a wide range of dynamic properties from well-separated modal frequencies to very closely spaced modal frequencies. The natural frequencies and modal damping ratios identified by the HHT method are compared with the theoretical values and those identified using the fast Fourier transform (FFT) method. The results show that the HHT method is superior to the FFT method in the identification of modal damping ratios of the structure with closely spaced modes of vibration. Finally, a 36-storey shear building with a 4-storey light appendage, having closely spaced modal frequencies and subjected to an ambient ground motion, is analyzed. The modal damping ratios identified by the HHT method in conjunction with the random decrement technique (RDT) are much better than those obtained by the FFT method. The HHT method performing in the frequency-time domain seems to be a promising tool for system identification of civil engineering structures.

• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.3
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• pp.320-329
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• 2017

In this research, we have calculated characteristics of wave-piercing high-speed planing hull, by using a RANS solver and overset grid method, for comparing with experimental measurements of that and simulating with several appendages, since the computed results of commercial CFD code look reasonable for the prediction of the performances of planing hulls on calm water in planing conditions. As a result, it is confirmed that the dynamic instability phenomena in pitch and heave motions (porpoising) occurred after a certain $Fn_V$, and effectively suppressed using some of appendages, especially the 0.5L spray rail is suppressed to 24-55 % in the pitch motion and 33-55 % in the heave motion. In spray phenomenon, 1L hard chine suppress spray effectively and it is effective to set the angle of appendages to be less than $0^{\circ}$ in order to suppress wave.

• BMB Reports
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• v.45 no.8
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• pp.427-432
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• 2012

Primary cilia, single hair-like appendage on the surface of the most mammalian cells, were once considered to be vestigial cellular organelles for a past century because of their tiny structure and unknown function. Although they lack ancestral motility function of cilia or flagella, they share common ground with multiciliated motile cilia and flagella on internal structure such as microtubule based nine outer doublets nucleated from the base of mother centrioles called basal body. Making cilia, ciliogenesis, in cells depends on the cell cycle stage due to reuse of centrioles for cell division forming mitotic spindle pole (M phase) and assembling cilia from basal body (starting G1 phase and maintaining most of interphase). Ciliary assembly required two conflicting processes such as assembly and disassembly and balance between these two processes determines the length of cilia. Both process required highly conserved transport system to supply needed substance to grow tip of cilia and bring ciliary turnover product back to the base of cilia using motor protein, kinesin and dynein, and transport protein complex, IFT particles. Disruption of ciliary structure or function causes multiple human disorder called ciliopathies affecting disease of diverse ciliated tissues ranging from eye, kidney, respiratory tract and brain. Recent explosion of research on the primary cilia and their involvement on animal development and disease attracts scientific interest on how extensively the function of cilia related to specific cell physiology and signaling pathway. In this review, I introduce general features of primary cilia and recent progress in understanding of the ciliary length control and signaling pathways transduced through primary cilia in vertebrates.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.12 no.1
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• pp.75-78
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• 2009

A peritoneal loose body is reported to develop because of torsion and separation of the epiploic appendages. The condition is usually symptomless and may be incidentally during abdominal surgery or autopsy. It usually occurs in middle-aged and elderly adults and is very rare in children. In this paper, we report a case of a peritoneal loose body in the pelvic cavity of a 10-year old-girl who presented with urinary frequency and left lower abdominal discomfort. A second plain X-ray film of the abdomen, obtained before surgery, in a different view than the first, revealed that the calcified mass had migrated to a lower position. The mass was laparoscopically resected, and histological examination revealed it to be a fibrotic nodule with central liquefaction and calcification.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.17 no.4
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• pp.263-265
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• 2014

Epiploic appendagitis is an inflammation of the epiploic appendage in which the small sacs projecting from the serosal layer of the colon are positioned longitudinally from the caecum to the rectosigmoid area. Epiploic appendagitis is rare and self-limiting; however, it can cause sudden abdominal pain in children. Epiploic appendagitis does not typically accompany other gastrointestinal diseases. Here, we report on a healthy eight-year-old girl who presented with abdominal pain, fever, vomiting, and diarrhea. Based on these symptoms, she was diagnosed with acute gastroenteritis, but epiploic appendagitis in the ascending colon was revealed in contrast computed tomography (CT). The patient was treated successfully with conservative management. CT is beneficial in diagnosis and further assessment of epiploic appendagitis. Pediatricians need to be aware of this self-limiting disease and consider it as a possible alternate diagnosis in cases of acute abdominal pain.

• Composites Research
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• v.15 no.3
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• pp.18-29
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• 2002

The bending vibration and thermal flutter instability of spacecraft booms modeled as circular thin-walled beams of closed cross-section and subjected to thermal radiation loading is investigated in this paper. The thin-walled beam model incorporates a number of nonclassical effects of transverse shear, primary and secondary warping, rotary inertia and anisotropy of constituent materials. Thermally induced vibration response characteristics of a composite thin walled beam exhibiting the circumferantially uniform system(CUS) configuration are exploited in connection with the structural flapwise bending-lagwise bending coupling resulting from directional properties of fiber reinforced composite materials and from ply stacking sequence. The numerical simulations display deflection time-history as a function of the ply-angle of fibers of the composite materials, damping factor, incident angle of solar heat flux, as well as the boundary of the thermal flutter instability domain. The adaptive control are provided by a system of piezoelectric devices whose sensing and actuating functions are combined and that are bonded or embedded into the host structure.