• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.110-110
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• 2011

The nanomechanical properties of fully lithiated and unlithiated silicon nanowire deposited on silicon substrate have been studied with atomic force microscopy. Silicon nanowires were synthesized using the vapor-liquid-solid process on stainless steel substrates using Au catalyst. Fully lithiated silicon nanowires were obtained by using the electrochemical method, followed by drop-casting on the silicon substrate. The roughness, derived from a line profile of the surface measured in contact mode atomic force microscopy, has a smaller value for lithiated silicon nanowire and a higher value for unlithiated silicon nanowire. Force spectroscopy was utilitzed to study the influence of lithiation on the tip-surface adhesion force. Lithiated silicon nanowire revealed a smaller value than that of the Si nanowire substrate by a factor of two, while the adhesion force of the silicon nanowire is similar to that of the silicon substrate. The Young's modulus obtained from the force-distance curve, also shows that the unlithiated silicon nanowire has a relatively higher value than lithiated silicon nanowire due to the elastically soft amorphous structures. The frictional forces acting on the tip sliding on the surface of lithiated and unlithiated silicon nanowire were obtained within the range of 0.5-4.0 Hz and 0.01-200 nN for velocity and load dependency, respectively. We explain the trend of adhesion and modulus in light of the materials properties of silicon and lithiated silicon. The results suggest a useful method for chemical identification of the lithiated region during the charging and discharging process.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.13 no.1
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• pp.33-39
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• 2002

Background and Objectives : The vocal fold nodules which were made by excessive contact or vibration of the vocal folds were classified to the soft nodule and the hard nodule in according to the hardness or the duration of nodule. Sometimes laryngologist saw the nodule to be located in different level. Authors thought that each nodule to be located in different level might have the different causes. Therefore we studied to know the relationship between the voicing technique and each vocal fold nodule to be located in different level. Materials and Methods : One-hundred forty nine patients who had the vocal fold nodule were evaluated. Sites and shapes of the vocal fold nodules were investigated using videostroboscopy. Videokymography was also used to scan the center of the vocal fold nodules during phonation and classified to several types. Same procedures were done on normal subject while he simulated the various types of voicing. And we compared the findings between both of them. Three different types of lesion can be distinguished. These are ML group that lesions were located from mid to low, MH group that lesions were located from mid to upper and HL group that lesions were located from lower to upper of the vocal folds. Results : The VKG findings of ML group and situation simulating with hard glottal attack and vocal fry were similar. MH group had a similar VKG findings with situation simulating with whispering or high pitch voicing. HL group had a similar VKG findings with situation simulating with loud voicing. Conclusions : Authors thought that each vocal fold nodule, which had different shapes and located in different level, related with the different types of voicing.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.22 no.6
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• pp.533-539
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• 2009

In this study, the femur, the tibia, the articular cartilage and the menisci are three dimensionally reconstructed using MR images of healthy knee joint in full extension of 26-year-old male. Three dimensional finite element model of the knee joint is fabricated on the reconstructed model. Also, the FE models of ligaments and tendons are attached on the biologically suitable position of the FE model. Bones, articular cartilages and menisci are considered as homogeneous, isotropic and linear elastic materials, and ligaments and tendons are modeled as truss element and nonlinear elastic springs. The numerical results show the contact pressure and the von Mises stress distribution in the soft tissues such as articular cartilages and menisci which can be regarded as important parameters to estimate the failure of the tissues and the pain of the patients.

• Journal of Fashion Business
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• v.18 no.5
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• pp.159-170
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• 2014

Recent concerns about the PFOA(perfluorooctanoic acid), have been increasing, which is generally applied in the water-repellent finishing process of textile products. It has been proven through animal testing to be harmful to humans, as possible carcinogens and neuro-toxic material. Thus U. S. Environmental Agency has gone as far as requiring the material to be eliminated in its entirety by 2015. As a viable alternative to this water-repellent finishing agent, the development of C6 product is gaining its popularity. The effects of PFOA finishing on the silk fabrics were examined, and we reviewed parameters of the needed process for optimizing appearance and functionality of silk fabrics treated with eco-friendly water-repellent finishing agent. Cross-linking agent affected the most on black color of reactive ink, among the physical properties. The contact angle reading was the highest in $8g/{\ell}$ of concentration for all fabrics. All the fabric specimens, subjected to the DTP and water repellent finishing, exhibited higher stiffness, where rayon specimen showed the highest, compared to the untreated specimens. The results may provide basic information leading to the development of value-added silk fabrics with water-repellency without excessive deterioration of the delicate appearance and inherent soft touch.

• 보존과학연구
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• s.19
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• pp.133-158
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• 1998

There are about 2,000 species of termite in the World, but one species of termite inhabits in the southern part of Korean peninsula. Termites are social insects that live in colonies. The colonies are composed of king, queen, soldiers and workers. Termite food consists of cellulose obtained from wood. Protozoa in their digestive tracts convert the cellulose into usable food. Korean termite is a subspecies of Reticulitermes speratus Kolbe, Rhinotermitidae. It's subterranean termite and the scientic name is R. speratus kyushensis Morimoto. The subterranean termite must nest in the soil in order to survival, and infest soft-wood which contact with the soil near the nest. There are several ways which subterranean termite infestations can be noticed. Atcertain times of the year during daylight hours, king and queen termites emerge from the colonies. The propose of these flight is to establish new colonies. The termite is a decomposer of biological ecosystem, but an invader in the preservation of cultural properties as like wood buildings. There are serveral control methods for the prevention of wood building from termite's damages. Those are biological control, ecological control, physical control and chemical control. Ecological and Physical control are the best methods in the new constructing wood-building. Fumigation which is a method of chemical control, is the best method for the building damaged by the termite. After the fumigation, we have totake wood & soil treatments for the building and nearby in order not to be reinvaded by the termites.

• Journal of the Korean Vacuum Society
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• v.18 no.4
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• pp.310-317
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• 2009

Vertical wet equipment for the BGA develop process was newly developed substituted for conventional horizontal wet equipment. The benefits of vertical equipment are that the pattern damages generated by the collision between the patterns and transferring rollers can be eliminated because the direct contact between the equipment's transferring units and the soft dry film patterns does not occurs. Taguchi experiment was conducted to optimize the process characteristics for the vertical equipment. The experiment was organized as the smaller the better problem which includes adequate uncontrollable factor and controllable factors. The uncontrollable factors are the 4 sides of two panels which are loaded to the equipment at the same time. By the analysis of the experiment, temperature of the develop chemicals and develop spraying time are analyzed as the main controllable factors. Finally, line pattern's minimum width which is not damaged for the develop process was improved from $13.8{\mu}m$ for the horizontal equipment to $10.4{\mu}m$ for the vertical equipment. And dot pattern's minimum width is improved from $22.1{\mu}m$ to $16.3{\mu}m$.

• Journal of the Korean Arthroscopy Society
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• v.14 no.3
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• pp.192-195
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• 2010

Subcoracoid impingement resulting from abnormal contact between the anterosuperior humerus and the anterior coracoacromial arch represents an uncommon source of anterior shoulder pain. Certain operative procedures can also alter the relationship between the coracoid and the lesser tuberosity, leading to impingement of the interventing soft tissue, including the subscapularis and the bursa. We describe an unique case of subcoracoid impingement with the tear of subscapularis tendon after the internal fixation of the fractured coracoid process with cannulated screw due to crowding of the coracohumeral space. Arthroscopic removal of the screw and repair of the subscapularis in our patient resulted in successful resolution of his symptoms. Although subcoracoid impingement is a rare cause of shoulder pain, failure to diagnose and treat this condition may represent a significant cause of failed shoulder surgery.

• Journal of Magnetics
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• v.10 no.3
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• pp.122-127
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• 2005

New classes of LC resonators for micro magnetic sensor device were proposed and fabricated. The first type LC resonator (Type I) consists of a small piece of microwire and two cylindrical electrodes at the end of the microwire without direct contact to its ferromagnetic core. In type I resonator the ferromagnetic core of the microwire and cylindrical electrodes act as an inductor and two capacitors respectively to form a LC circuit. The second type LC resonator (Type II) consists of a solenoidal micro-inductor with a bundle of soft magnetic microwires as a core. The solenoidal micro-inductors fabricated by MEMS technique were $500\sim1,000\;\mu{m}$ in length with $10\sim20$ turns. A capacitor is connected in parallel to the micro-inductor to form a LC circuit. A tiny glass coated $CO_{83.2}B_{3.3}Si_{5.9}Mn_{7.6}$ microwire was fabricated by a glass-coated melt spinning technique. A supergiant magneto-impedance effect was found in a type I resonator as much as 400,000% by precise tuning frequency at around 518.51 MHz. In type II resonator the changes of inductance as a function of external magnetic field in micro-inductors with properly annealed microwire cores were varied as much as 370%. The phase angle between current and voltage was also strongly dependent on the magnetic field. The drastic increments of magnetoimpedance at near the resonance frequency were observed in both types of LC resonators. Accordingly, the sudden change of the phase angle, as large as $180^{\circ}C$, evidenced the occurrence of the resonance at a given external magnetic field.

• Physical Therapy Rehabilitation Science
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• v.9 no.4
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• pp.302-308
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• 2020

Objective: The endurance and strength of deep neck flexor (DNF) muscles have a major role on the function and stability of the cervical spine. In recent years, there has been a lack of research that have investigated the muscle tone of the superficial neck muscles. The purpose of this study was to examine the relationship of between contraction ratio of the DNF and sternocleidomastoid (SCM) muscles, DNF endurance, and muscle tension of the neck muscles. Design: Cross-sectional study. Methods: Forty-seven subjects (male=20, female=27) participated in this study. The muscle tone of the upper trapezius (UT), SCM, and suboccipital (SO) muscle was measured using a contact soft tissue tone-measuring instrument. For the contraction ratio of the SCM and longus colli muscle, the thickness of the relaxation and maximum contraction state of the SCM and longus colli muscles were assessed using a diagnostic ultrasound measuring instrument and a pressure biofeedback unit. The deep neck flexor endurance test (DNFET) was performed in a cranio-cervical flexion posture. The correlations between the measured variables were investigated. Results: The relationship between the DNFET and SO tone showed a significant negative correlation (p<0.05). The relationship between the DNFET and contraction ratio showed a significant positive correlation (p<0.01). There was no significant correlation between the DNFET and SCM and UT tone. Conclusions: This study confirmed that there is a relationship between DNF endurance, DNF activation, and SO tone. The information on the results of this study may be used as a reference that can be actively applied in the clinical environment.

• Journal of The Korean Society of Integrative Medicine
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• v.9 no.1
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• pp.123-131
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• 2021

Purpose : The time spent using smart devices is constantly increasing, particularly in recent times. Using smart devices for a long time with an incorrect posture may lead to cerebral palsy (CP), instability, and abnormal muscle tone. Therefore, we aimed to investigate the relationships among cervical instability, deep neck flexor (DNF) activity, range of motion (ROM), and muscle tonus. Methods : Fifty subjects with CP participated in this study, and they were physiotherapists at W Hospital in Daejeon. Those who voluntarily participated in the research were selected as candidates who fulfilled the selection criteria. According to an instability test, 25 subjects were assigned to the instability and control groups. All subjects first underwent the instability test to be allocated to the appropriate group. Those in the instability group tested positive on the instability test. The Neck Disability Index (NDI), ROM, muscle tone, and DNF activity were measured to evaluate their relationships. The DNF strength and endurance were measured using a cranio-cervical flexion test. The upper trapezius (UT), sternocleidomastoid (SCM), and suboccipital (SO) muscle tones were measured using a contact soft tissue tone measuring instrument. The statistical significance level was set to .05. Results : There were significant differences in the flexion, extension, and rotation of the cervical ROM (CROM) between the two groups (p<.05). The SCM, UT, and SO muscle tones were significantly different between the two groups (p<.05). The DNF strength and endurance showed a significant difference between the two groups (p<.05). Conclusion : We found that there were significant increases in the CROM and muscle tone and decrease in the DNF strength and endurance in the instability group. This indicated that cervical instability is affected by the DNF strength and endurance. We may recommend DNF exercises in cases of cervical instability in clinical environments.