• Journal of mucopolysaccharidosis and rare diseases
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• v.3 no.1
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• pp.1-8
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• 2017

Mucopolysaccharidosis (MPS) type III, or Sanfilippo syndrome is a rare autosomal recessive lysosomal storage disorder. It is caused by a deficiency of one of four enzymes involved in the degradation of the glycosaminoglycan (GAG) heparan sulfate. The resultant cellular accumulation of heparan sulfate causes various clinical manifestations. MPS III is divided into four subtypes depending on the deficient enzyme: MPS IIIA, MPS IIIB, MPS IIIC and MPS IIID. All the subtypes show similar clinical features and are characterized by progressive degeneration of the central nervous system (CNS). Main purpose of the treatment for MPS III is to prevent neurologic deterioration. However, conventional enzyme replacement therapy has a limitation due to inability to cross the blood-brain barrier. Several experimental treatment options for MPS III are being developed.

• Proceedings of the Acoustical Society of Korea Conference
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• autumn
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• pp.427-432
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• 1999

When a high-speed train enters a tunnel, a compression wave is generated. This wave subsequently emerges from the exit portal of the tunnel, which causes an impulsive noise called 'Sonic boom' or 'micro-pressure wave'. In the present study, new method is presented for prediction of sonic boom noise, especially focusing on the effect of the nose shape of the train on the resultant noise. Acoustic theory for monopole source is used to represent a nose shape of the train in wave equation. Compression wave propagation in tunnel considering tunnel track condition and emission of sonic boom was calculated. The predicted compression waves and impulsive sound waves are compared with recent measurements, and show reasonable agreements.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.28 no.1
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• pp.4-13
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• 2017

The seeds of addiction are typically sown years prior to the onset of addictive substance use or engagement in addictive behaviors, due to the priming of the reward pathway (RewP) by alterations in the mechanism of stress-signaling from the hypothalamic-pituitary-adrenal axis (HPA) and related pathways. Excessive stress from a single-event and/or cumulative life experiences during childhood, such as those documented in the Adverse Childhood Experiences Study, is translated into neurobiological toxicity that alters the set-point of the HPA axis and limbic system homeostasis [suggested new term: regulation pathway (RegP)]. The resultant alteration of the RegP not only increases the risk for psychiatric and physical illness, but also that for early onset and chronic addictions by dysregulating the RewP. This paper reviews the interface of these symbiotic pathways that result in the phenotypic pathology of emotional dysregulation, cognitive impairment, and compulsive behaviors, as well as morbidity and shorter life expectancy when dysregulated by chronic stress.

• Journal of Trauma and Injury
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• v.29 no.4
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• pp.187-190
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• 2016

With the development of safety measures for employees who work with dangerous machinery, the frequency of amputation injuries has been decreasing with resultant decrease in replantation procedures. However, in some patients with major amputation injury, replantation is still necessary for the preservation of limb and it's function. The replantation of the upper extremity (UE) is a complex and technically demanding surgical procedure. For the successful replantation of UE, the type of injury, reconstruction sequence, ischemic time, and other combined injury of patient should be considered. We report a case of major amputation of UE by guillotine-type injury and discuss the treatment process of this patient.

• Journal of the Korean institute of surface engineering
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• v.50 no.3
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• pp.155-163
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• 2017

In this study, the effects of the concentration of metal ions and the applied current density in the Sn-Ag plating solutions were examined in regards to the resulting composition and morphology of the solder bumps' surface. Furthermore the effect of any impurities present in the methanesulfonic acid used as a base acid in the Sn-Ag solder plating solution on the stability of plating solution as well as the characteristics of the Sn-Ag alloys films was also explored. As expected, the uniform bump was obtained by means of removing impurities in the plating solution. Consequently the resultant solder bump was obtained in an optimal current density of the range of $1A/dm^2$ to $15A/dm^2$, which has acceptable bump shape and surface roughness with 12inch wafer trial results.

• Geomechanics and Engineering
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• v.8 no.4
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• pp.523-540
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• 2015

Based on limit equilibrium principles, this study presents a theoretical derivation of a new analytical formulation for estimating magnitude and lateral earth pressure distribution on a retaining wall subjected to seismic loads. The proposed solution accounts for failure wedge inclination, unit weight and friction angle of backfill soil, wall roughness, and horizontal and vertical seismic ground accelerations. The current analysis predicts a nonlinear lateral earth pressure variation along the wall with and without seismic loads. A parametric study is conducted to examine the influence of various parameters on lateral earth pressure distribution. Findings reveal that lateral earth pressure increases with the increase of horizontal ground acceleration while it decreases with the increase of vertical ground acceleration. Compared to classical theory, the position of resultant lateral earth force is located at a higher distance from wall base which in turn has a direct impact on wall stability and economy. A numerical example is presented to illustrate the computations of lateral earth pressure distribution based on the suggested analytical method.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.7 no.2
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• pp.276-286
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• 1995

In this study, pressure drop and heat transfer coefficients were measured in tubes with three dimensional roughness. Dimples were made by rotating the saw-tooth shaped finning disc on the outer tube surface. Resultant dimple shape was oval. Friction and heat transfer tests were performed with a range of roughness variables-roughness height 'e', axial roughness pitch 'p', circumferential roughness pitch 'z'. Within the test range, tube with e=0.5mm, z=5mm, p=3mm performed best. The efficiency ratio(rati of the heat transfer improvement and the pressure drop increase) of the tube approached 1.0 at low Reynolds number, and it was higher than that of the two-dimensional roughess tube of the same roughness height. Test data were predicted by 'discrete element method'. Results show that discrete element method underpredicts the friction data by 2% to 32%, and overpredicts the heat transfer data by-12% to 113%.

• Journal of Information Processing Systems
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• v.11 no.2
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• pp.184-204
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• 2015

Fuzzy Formal Concept Analysis (FCA) is a mathematical tool for the effective representation of imprecise and vague knowledge. However, with a large number of formal concepts from a fuzzy context, the task of knowledge representation becomes complex. Hence, knowledge reduction is an important issue in FCA with a fuzzy setting. The purpose of this current study is to address this issue by proposing a method that computes the corresponding crisp order for the fuzzy relation in a given fuzzy formal context. The obtained formal context using the proposed method provides a fewer number of concepts when compared to original fuzzy context. The resultant lattice structure is a reduced form of its corresponding fuzzy concept lattice and preserves the specialized and generalized concepts, as well as stability. This study also shows a step-by-step demonstration of the proposed method and its application.

• Wind and Structures
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• v.27 no.4
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• pp.247-254
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• 2018

In this paper, a simple first-order shear deformation theory is presented for dynamic behavior of functionally graded beams. Unlike the existing first-order shear deformation theory, the present one contains only three unknowns and has strong similarities with the classical beam theory in many aspects such as equations of motion, boundary conditions, and stress resultant expressions. Equations of motion and boundary conditions are derived from Hamilton's principle. Analytical solutions of simply supported FG beam are obtained and the results are compared with Euler-Bernoulli beam and the other shear deformation beam theory results. Comparison studies show that this new first-order shear deformation theory can achieve the same accuracy of the existing first-order shear deformation theory.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.1 s.173
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• pp.225-231
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• 2000

Dimensional synthesis of planar and spatial mechanisms mostly requires solution-finding, procedure for a system of polynomial equations. In case the system is nonlinear, numerical techniques like Newton-Raphson are often used. But there are no logical ways for finding all possible solutions in such iterative methods. In this paper, algebraic elimination is used to get all solutions for the synthesis of 5-SS spatial mechanism with seven prescribed positions. The proposed algorithm is more suitable for computer implementation and takes less time than existing one. Two numerical examples are given to demonstrate the implemented algorithm.