• Journal of the Korean Academy of Clinical Electrophysiology
• /
• v.8 no.1
• /
• pp.43-50
• /
• 2010

Purpose : The objective of this study is to effect of an aquatic rotation control and obstacle avoidance when conducted underwater on hemiplegia patient's balance ability and vestibular function. Methods : Twelve hemiplegia patients participated and were randomly assigned to a control group(I) with standard physical therapy and an aquatic group(II) with an aquatic rotation control, obstacle avoidance and standard physical therapy as well. The aquatic group trained using a Halliwick rotation control and obstacle avoidance through 3 times per week over 6 weeks. For all subjects, vestibular function, their balance, the change of electrooculogram (EOG), the change of accelerometer axis and torsiometer according to visual sense, vestibular sense with galvanic vestibular stimulation (GVS) or not during leg close stance were measured. Results : The EOG in the vertical and horizontal (p<0.05) were both significantly lowered. The change was significantly lower in the trajectory range of motion of trunk and spine with torsiometer when leg close stand (p<0.01) and leg close stand with GVS (p<0.01). The centre of gravity accelerated, there were reduced significantly difference X and Y axis of accelerometer during the closing of the leg without vision (p<0.05). There were reduced significantly difference X and Z axis of accelerometer during the closing of the leg with GVS (p<0.05). There were reduced significantly difference X and Z axis of accelerometer during the closing of the leg and close eyes with GVS (p<0.05). Conclusion : The balance ability, vestibular system and postural control is improved.

• Convergence Security Journal
• /
• v.14 no.3_2
• /
• pp.3-12
• /
• 2014

The government was fully aware of the gravity of a recent massive leak of personal information of credit card users. Meanwhile, the government just took a light disciplinary action by imposing a fine, but it showed its intention to strengthen the regulations by taking the severest disciplinary action. The tightened regulations against personal information leak will be applied to the private security industry without exception to protect individual people's property and lives if such an incident occurs in that industry that deals with a wide variety of personal information such as CCTV data or privacy information all the time. The purpose of this study was to examine the state of the protection and management of personal information for service users among private security firms in an effort to suggest some reform measures. The findings of the study were as follows: First, administrators or managers who are involved with personal information protection should make a full-fledged effort to gather information. Second, counseling or related programs should be provided for small and mid-sized security firms to guarantee thorough personal information protection. Third, Korea Security Association should improve the educational system related to personal information protection to resolve problems with this education currently provided for managers and employees of these companies.

• Journal of Biosystems Engineering
• /
• v.6 no.1
• /
• pp.73-82
• /
• 1981

The physical properties of grain are very important for the design of handling, sorting, processing, and storage system. On the physical properties of grain, volume, bulk density, true density, specific gravity, and porosity arc the major factors affecting the thermal properties of grain. This study was conducted to determine experimentally the above physical properties of rough rice (3 Japonica-type, 3 Indica-type) and barley (covered, naked) as a function of moisture content ranged from about 10% to 25% (w.b). The results of this study are summarized as follows; 1. The volume of grain kernel increased with moisture content for both rice and barley. The volume of those grain kernel was in the range of $2.2068{\times}10^{-8}{\sim}3.3960{\times}10^{-8}m^3$ at the moisture content of 14%. 2. The bulk density of rice increased linearly with moisture content for Japonica-type rough rice and quadratically for Indica-type rough rice, but the bulk density of barley decreased linearly with moisture content. The bulk density of the grain was in the range of 501.14~689.13kg/$m^3$ at the moisture content of 14%. 3. The true density of whole grain decreased linearly with moisture content, and was in the range of 1019.49~1139.75kg/$m^3$ at the moisture content of 14%. 4. The porosity of rice decreased linearly with moisture content for Japonica-type rough rice and quadratically for Indica-type rough rice, but the porosity of barley increased linearly with moisture content. The porosity of the grain was in the range of 39.51~50.83% at the moisture content of 14%. 5. The regression equations of the physical properties such as volume, bulk density, true density, and porosity of the grain were determined as a function of moisture content.

• Journal of Biosystems Engineering
• /
• v.32 no.6
• /
• pp.416-421
• /
• 2007

Physical damage to fruits and vegetables caused by shock degrades the value of product in the fresh market. In order to design a product/packaging system to protect the product, the G-factor to the product that causes shock damage needs to be determined. The shock fragility of organisms such as fruits with a concept correspondent to the G-factor of industrial products was calculated and we defined the allowable bio-shock fragility index as the value divided peak acceleration that was generated in safe drop height by standard acceleration of gravity. We did modeling for safe drop hight that would prevent fruits from damage by drop tests and tried to estimate the allowable bio-shock fragility index of pears and apples for optimum packaging design. The bio-shock fragility index of pears was in the range of $0.74{\sim}2.29\;G$, while apples had a slightly higher value than that of pears, of $0.51{\sim}2.98\;G$. This result shows accordance with the general fact that apples have a firmer structure and get less damage from the same impact. Based on this result, it is possible to create an optimum packaging design by providing a damage standard by impact.

• Journal of Veterinary Clinics
• /
• v.37 no.2
• /
• pp.61-66
• /
• 2020

Nickel is a nutritionally essential trace element that plays an important role in the immune system of several animal species. The aim of this study was to examine the effect of nickel chloride on chemotactic activity of peripheral blood polymorphonuclear cells (PMNs) and whether this effect is associated with interleukin (IL)-8 and a nuclear factor-kappa B (NF-κB)-dependent pathway. Peripheral blood mononuclear cells (PBMCs) and PMNs were isolated by Percoll solution (Specific gravity; 1.080) and 1.5% dextran treatment, respectively. A modified Boyden chamber assay was used to measure the chemotactic activity of PMNs. The level of IL-8 in culture supernatant from PBMCs was measured by enzyme-linked immunosorbent assay (ELISA). Both of PBMCs and PMNs exhibited a low viability when cultured with concentration of greater than 1,000 μM of nickel chloride for 24 h. Thus, nickel chloride was used at concentration of 500 μM, which preserved cell viability. Treatment with nickel did not directly affect the chemotactic activity of PMNs. However, the chemotactic activity of PMNs was remarkably increased by culture supernatant from PBMCs treated with nickel chloride (500 μM) for 24 h. Recombinant porcine IL-8 polyclonal antibody (pAb) neutralized the enhancing effect on the chemotactic activity of PMNs by culture supernatant from PBMCs treated with nickel and this culture supernatant had higher IL-8 levels than the culture supernatant from untreated PBMCs. In addition, n-tosyll-phenylalanine chloromethyl ketone (TPCK), a NF-κB inhibitor, antagonized the enhancing effect on the chemotactic activity of PMNs by the culture supernatant from PBMCs treated with nickel. These results suggested that nickel stimulates porcine PBMCs to produce IL-8, which increases the chemotaxis of PMNs via NF-κB-dependent pathway.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.35 no.7
• /
• pp.827-833
• /
• 2011

In this study, a simulation model to estimate the current-collection performance of a high-speed train was developed by using a commercial finite element analysis software, SAMCEF. A three-dimensional springDdamperDmass model of a pantograph was created, and its reliability was validated by comparing the receptance of the model to that of the actual pantograph. The wave propagation speed of the catenary model was compared with the analytical wave propagation speed of the catenary system presented in the UIC 799 OR standard. The length of the droppers was controlled, and the pre-sag of the contact wire due to gravity was considered. The catenary and the pantograph were connected by using a contact element, and the contact force variation when the pantograph was moved at velocities of 300 km/h and 370 km/h was obtained. The average, standard deviation, maximum, and minimum values of the contact force were analyzed, and the effectiveness of the developed simulation model was examined.

• Earthquakes and Structures
• /
• v.19 no.4
• /
• pp.273-286
• /
• 2020

The pile group foundation is widely used for gravity pier of high-speed railway bridges in China. If a moderate or strong earthquake occurs, the pile-surrounding soil will exhibit obvious nonlinearity and significant pile group effect. In this study, an improved pushover analysis model for the pile group foundation with consideration of pile group effect is presented and validated by the quasi-static test. The improved model uses simplified springs to simulate the soil lateral resistance, side friction and tip resistance. PM (axial load-bending moment) plastic hinge model is introduced to simulate the impact of the axial force changing of pile group on their elastic-plastic characteristics. The pile group effect is considered in stress-stain relations of the lateral soil resistance with a reduction factor. The influence factors on nonlinear characteristics and plastic hinge distribution of the pile group foundation are discussed, including the pier height, longitudinal reinforcement ratio and stirrup ratio of the pile, and soil mechanical parameters. Furthermore, the displacement ductility factor, resistance increase factor and yielding stiffness ratio are provided to evaluate the seismic performance of soil-pile system. A case study for the pile group foundation of a railway simply supported beam bridge with a 32 m-span is conducted by numerical analysis. It is shown that the ultimate lateral force of pile group is not determined by the yielding force of the single one in these piles. Therefore, the pile group effect is essential for the seismic performance evaluation of the railway bridge with pile group foundation.

• Journal of Powder Materials
• /
• v.8 no.3
• /
• pp.151-156
• /
• 2001

MgO based nanocomposite powder including ferromagnetic iron particle dispersions, which can be available for the magnetic and catalytic applications, was fabricated by the spray pyrolysis process using ultra-sonic atomizer and reduction processes. Liquid source was prepared from iron (Fe)-nitrate, as a source of Fe nano-dispersion, and magnesium (Mg)-nitrate, as a source of MgO materials, with pure water solvent. After the chamber were heated to given temperatures (500~$^800{\circ}C$), the mist of liquid droplets generated by ultrasonic atomizer carried into the chamber by a carrier gas of air, and the ist was decomposed into Fe-oxide and MgO nano-powder. The obtained powders were reduced by hydrogen atmosphere at 600~$^800{\circ}C$. The reduction behavior was investigated by thermal gravity and hygrometry. After reduction, the aggregated sub-micron Fe/MgO powders were obtained, and each aggregated powder composed of nano-sized Fe/MgO materials. By the difference of the chamber temperature, the particle size of Fe and MgO was changed in a few 10 nm levels. Also, the nano-porous Fe-MgO sub-micron powders were obtained. Through this preparation process and the evaluation of phase and microstructure, it was concluded that the Fe/MgO nanocomposite powders with high surface area and the higher coercive force were successfully fabricated.

• Textile Coloration and Finishing
• /
• v.28 no.3
• /
• pp.189-194
• /
• 2016

The objectives of this research were to study the effect of salt-shrinkage finishing of silk on shrinkage degree and dyeing property of cochineal, and to investigate the efficacy of obtained results for imparting surface design effect on silk fabric. Ultimately it was aimed to suggest a technical process for developing natural dyed silk products with diverse design. Premordanted silk fabric was treated with $Ca(NO_3)_2$ solution(gravity: 1.45) at $90^{\circ}C$ for 1 min, washed, dried for further evaluation. The shrinkage of salt-treated fabric was calculated. The effects of salt treatment on the dye uptake of cochineal and colorfastness were investigated. The degrees of shrinkage were 10% and 3% for warp and weft, respectively. The salt treatment resulted in improving dye uptake of cochineal slightly. In addition, it improved colorfastness to washing and light. On the basis of the results, a technical process composed of premordanting, salt treatment and natural dyeing was suggested and using the process, two examples of textile design were presented. It can be concluded to impart various three dimensional surface design effect on silk fabric by applying salt-shrinkage finishing with combination of natural dyeing and mordanting.

• Journal of Navigation and Port Research
• /
• v.27 no.5
• /
• pp.465-471
• /
• 2003

A coastwise chemical tanker sailing at full speed has capsized during turning in calm water. In the previous paper, we investigated the reasons of the accident by demonstrating the proper correction for the free surface effect of the liquid cargo and the bow-sinkage effect. In this paper, we also carry out model experiments of a transverse pressure under the seawater and an outward heel moment according to the heel angle and rudder angle, on the basis of radius of turning circle, ship's speed and drift angle of model ship occurring in turning. It is also shown that the flooding of seawater onto the deck occurring in turning generated a significant outward heel moment and increased the vertical distance between the center of gravity of the ship and the center of lateral water drag.