• Journal of the Korean Institute of Telematics and Electronics S
• /
• v.34S no.11
• /
• pp.80-92
• /
• 1997

This research focuses onan efficient control method of temperature for multiple points using only one processor. For a yarn production system, the surface temperature control of heaters are very important for quality control. Therefore, we designed a temperature controller for a draw and twist machine and applied Fuzzy-PWM algorithm to the controller. If we use a processor for the temperature control of multiple points with the conventional ON/OFF control, the control performance of the system becomes poor. To overcome these problems, we developed a new Fuzzy-PWM algorithm for the adjustment of power rate to the heaters in the conventional ON/OFF control. It is shown that this algorithm has the same effects as the PID algorithm for the temperature control of each point. The proposed algorithm is robust against the production condition and environment such as the reference temperature and the thickness of yarn, since the power rate to the heater is adjusted by Fuzzy Rules derived from the values of the reference termperatureand the thickness of yarn. To obtain optimal Fuzzy rulees, the control simulations are perfodrmed through the modelling of the heater and simulation of Fuzzy rules. This algorithm is applied for the multiple pont temperature controller and showed satisfactory performance.

• Journal of Mechanical Science and Technology
• /
• v.16 no.4
• /
• pp.512-521
• /
• 2002

The flap-lag-torsion coupled aeroelastic behavior of a hingeless rotor blade with composite flexures in hovering flight has been investigated by using the finite element method. The quasisteady strip theory with dynamic inflow effects is used to obtain the aerodynamic loads acting on the blade. The governing differential equations of motion undergoing moderately large displacements and rotations are derived using the Hamilton's principle. The flexures used in the present model are composed of two composite plates which are rigidly attached together. The lead-lag flexure is located inboard of the flap flexure. A mixed warping model that combines the St. Versant torsion and the Vlasov torsion is developed to describe the twist behavior of the composite flexure. Numerical simulations are carried out to correlate the present results with experimental test data and also to identify the effects of structural couplings of the composite flexures on the aeroelastic stability of the blade. The prediction results agree well with other experimental data. The effects of elastic couplings such as pitch-flap, pitch-lag, and flap-lag couplings on the stability behavior of the composite blades are also investigated.

• Journal of Biosystems Engineering
• /
• v.38 no.2
• /
• pp.163-170
• /
• 2013

Purpose: The purpose of this study is to provide analysis of physiological, biomechanical responses occurring from the operation to lifting or twist lifting task appears frequently in agricultural work. Methods: This study investigated the changes of physiological factors such as heart rate, heart rate variability (HRV) and biomechanical factors such as physical activity and kinetic analysis in the task of twisting at the waist while lifting. Results: Heart rates changed significantly with the workload. The result indicated that the workload of 2 kg was light intensity work, and the workload of 12 kg was hard intensity work. Physical activity increased as the workload increased both on wrist and waist. Besides, stress index of the worker increased with the workload. Dynamic load to herniated discs was analyzed using inertial sensor, and the angular acceleration and torque increased with the workload. The proposed measurement system can measure the recipient's physiological and physical signals in real-time and analyzed 3-dimensionally according to the variety of work load. Conclusions: The system we propose will be a new method to measure agricultural workers' multi-dimensional signals and analyze various farming tasks.

• Composites Research
• /
• v.28 no.4
• /
• pp.204-211
• /
• 2015

This paper presents a theory related to a two-dimensional linear cross-sectional analysis, recovery relationship and a one-dimensional nonlinear beam analysis for composite wing structure with initial twist. Using VABS including a related theory, the design process of the composite rotor blade has been described. Cross-sectional analysis was performed at cutting point including all the details of geometry and material. Stiffness matrix and mass matrix were linked to each section to make 1D beam model. The 3D strain distributions within the structure were recovered based on the global behavior of the 1D beam analysis and visualize numerical results.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.25 no.8
• /
• pp.1408-1419
• /
• 2001

The purpose of this study was to investigate the fashion trends of last three years and how the trends were imaged by the structural characteristics of the fabrics. The characteristics for 897 fabrics were analyzed from four kinds. eleven volumes of fashion trend magazines. From these magazines, three panels categorized by their frequencies as nine images such as natural, innocent, ethnic, childish, casual, classic, modern and technical, Sub-images of each image such as rustic, irregular, decorative, etc were also categorized. For the each image, fiber contents and structural characteristics of weave type, weight, density, yarn size, twist and fabric finishes were investigated in terms of frequency, range and mean, Results showed that chiffon and organza seemed to have very specific images and used to represent specifically the romantic or ethnic images; whereas voile and jersey was used to represent various images. For S/S seasons, most popular fiber type was cotton. The weave type was not the important factor to give variations in images; plan weave exclusively used irrespective of image. For the romantic, ethnic and innocent images, rather light fabrics were used. For the childish and natural, medium weights, and for the technical, modern and classic images heavy weight fabrics were used. Vaious finishes were employed to represent specific images.

• Journal of Korean Neurosurgical Society
• /
• v.62 no.2
• /
• pp.144-152
• /
• 2019

Treatment of chronic subdural hematoma (CSDH) is relatively straightforward, however, there is still some debate regarding the best strategy for treatment. The most practical recommendations of up to date were identified by a review of literature. The author reviewed the literature on CSDH management from the past to now to identify the best methods. Till 1970s, craniotomy was the most commonly used method. Burr hole (BH) became the most preferred method from 1980s. In 1977, twist drill (TD) craniostomy was introduced. Closed system drainage after a BH or a TD became the most frequently used surgical method. Although nonsurgical treatment is often successful, trephination has more advantages, such as rapid resolution of the symptoms and short period of hospitalization. Nonsurgical treatment is possible in asymptomatic patients with a small CSDH. For the symptomatic patients with CSDH, trephination is the treatment of choice, either by BH or TD. In gray zone between surgery and medical treatment, shared decision making can be an ideal approach. For the recurrent CSDHs, repeated trephination is still effective for patients with a low risk of recurrence. If the risk of recurrence is high, additional management would be helpful. For the refractory CSDHs, it is necessary to obliterate the subdural space.

• International Journal of Advanced Culture Technology
• /
• v.6 no.2
• /
• pp.100-106
• /
• 2018

Sometimes, literary therapy is to create an abscission layer at the mind and remove the signifier of love, by the abscission layer. The purpose of this study is to reveal the mechanism of literary therapy by mutation in human-created sentences and to activate literary therapy. In Gosijo, the abscission layer of Seo Gyeongdok's mind is present in the layer of the "falling leaf" of the his Sijo's last sentence, and the abscission layer of Hwang Jin-yi's mind exists in the layer of the "falling leaf" of the her Sijo's last sentence. The "falling leaf" created by the abscission layer of Seo Gyeongdok's sentence acts as an action potential to the nervous system of Hwang Jin-yi. In Hwang Jin-yi's Sijo, the abscission layer is also activated, forming a "leaf". Hwang Jin-yi's Sijo constructs a new sensory layer that is extended and mutated more than the meaning of space between lines of Seo Gyeongdok's Sijo. In her Sijo, Hwang Jin-yi twists and twists Seo Gyeongdok's sentences to squeeze the sound. She accepts the Seo Gyeongdok's sentences and twists in the first sentence and twists out of the second sentence once more to produce the mutation in the last sentence. As a result of her sentence twist, Seo Kyung-duk's visual sense of "falling leaf" is mutated into a "falling leaf's sound" of auditory sense. This mutation process works as a healing mechanism in the human body. If this study will continue in the future, it will be possible to activate literary therapy by Sijo.

• Journal of the Korean Crystal Growth and Crystal Technology
• /
• v.29 no.1
• /
• pp.32-38
• /
• 2019

Carbon material was used for the new module-type bicycle accessory focusing on the user convenience through service design methodology. In the case of using the existing carbon material, the impact could not be endured while riding the bicycle and there was the case of breaking. To resolve this kind of problem, the new type of material (S Foam Core material) was applied. The intensity, twist intensity, shock absorbing power, and vibration were measured for the existing carbon material and the S Foam Core material. As a result, the S Foam Core material showed more outstanding results than the existing carbon material. This study produced prototype with the S Foam Core material to verify the performance through tests and report the result.

• Proceedings of the Korean Vacuum Society Conference
• /
• 1999.07a
• /
• pp.192-192
• /
• 1999

SIMS(Secondary Ion Mass Spectrometry)는 다른 표면 분석장비와 비교하여^g , pp m,^g , pp b 단위의 미량분석이 가능한 장비로서, 특히 depth Profiling을 위한 dynamic SIMS는 Mass Spectrometer의 종류에 따라 Quadrupole SIMS (Q-SIMS)와, Magnetic Sector SIMS (M-SIMS)로 분류된다. 한편, Q-SIMS와 달리 M-SIMS의 경우, Transmission을 높여 주기 위해 Sample Holder에 수 keV의 bias를 걸어 주는데, 이로 인하여 분석 원소에 대한 Sensitivity가 향상되어 지는 반면, RSF의 변화와 같은 분석상의 Artifact가 발생하게 된다. 일반적으로 Q-SIMS의 경우에는 RSF의 RSD(Relative Standard Deviation)가 1%이내에서 보고되고 있지만 M-SIMS에 있어서는 이러한 Deviation이 M-SIMS보다 크게 나타난다. 이 차이는 주로 Sample Holder와 Immersion Lens 사이에 형성되는 Magnetic Field의 왜곡과 Spectrometer의 문제로부터 발생한다. 본 논문에서는 Sample Holder의 종류 및 holder so window 위치에 따라 RSF의 차이를 측정하고 그 data를 RS/1 통계 Package를 이용하여 계량적으로 검증하였으며, 그 차이의 원인과 대책을 제시하고자 한다. 실험에 사용된 Sample은 Si(100) p-type Wafer에 Boron을 이온 주입하여 제작하였다. 이온 주입 장비는 Varian E-500HP이며, 5.0E13 ions/cm2의 dose양을 80keV의 Energy로 각각 7도와 22도의 Tilt와 Twist Angle로 이온 주입을 하였다. SIMS분석에 사용된 Sample Holder는 각각 3 Hole, 9 Hole Type HOlder이며, 분석은 Cameca IMS-6f를 사용하여 B에 대한 Matrix Peak으로 28Si++를 얻었다. 실험 결과 3 Hole Type Sample Holder의 경우 RSF의 RSD는 5.84%, 9Hle Type Sample Holder의 경우는 14.3%로 나타났으나 분석 Window의 위치에 따르는 Grouping을 실시한 결과, 3 Hole Type Sample Holder의 경우 1.2%, 9Hole Type Sample Holder의 경우 9.8%로 RSF의 변화가 감소하였다. 이러한 Deviation은 Sample Holder를 Mount시킬 때 세 개의 Screw를 이용하여 Immersion Lens와의 평형을 잡아주기 때문에 발생하며, 이 Munting을 정확히 해줌으로써 RSF의 변화를 줄일 수 있으나, 실제로 완벽한 Mounting이 불가능하기 때문에 RSF를 일정하게 하기 위해서는 Sample Holder so Window의 취치를 일정하게 설정한 후 분석을 실시해야 한다고 판단된다.

• Asian Pacific Journal of Cancer Prevention
• /
• v.14 no.11
• /
• pp.6305-6309
• /
• 2013

Background: TIAM2, a Rac guanine nucleotide exchange factor, is closely associated with cell adherence and migration. Here, we aimed to investigate the role of TIAM2 in non-small cell lung cancer (NSCLC) cells. Materials and Methods: A small interference RNA (siRNA) was introduced to silence the expression of TIAM2. Invasion and motility assays were then performed to assess the invasion and motility potential of NSCLC cells. GST-pull down assays were used to detect activation of Rac1. Results: TIAM2 was highly expressed in NSCLC cells. Knockdown of TIAM2 inhibited the invasion and motility, and suppressed activation of Rac1. Further experiments demonstrated that knockdown of TIAM2 could up-regulate the expression of E-cadherin, and down-regulate the expression of MMP-3, Twist and Snail. Conclusions: Our data suggest that TIAM2 can promote invasion and motility of NSCLC cells. Activation of Rac1 and regulation of some EMT/invasion-related genes may be involved in the underlying processes.