• Journal of Welding and Joining
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• v.30 no.6
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• pp.36-41
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• 2012

General condensers consist of many tubes supported by tube sheets and support plates to prevent the deflection of the condenser tubes. When a fluid at high pressure and temperature runs over the tubes for the purpose of transferring heat from one medium to another, the tubes vibrate and their surface comes into contact with the support plates. This vibration causes damage to the tubes, such as cracks and wear. We propose an ultrasonic guided wave technique to detect the above problems in the support plate region. In the proposed method, the ultrasonic guided wave mode, L(0,1), is excited using an internal transducer probe from a single position at the end of the tube. In this paper, we present a preliminary experimental verification using a super stainless tube and show that the defects can be discriminated from the support signals in the support region.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.2313-2318
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• 2003

By means of flexible forming processes in sheet metal manufacturing it is possible to produce parts of complex geometry within short manufacturing time. These procedures are suitable especially for prototyping or adjustment of deformation. Here formative procedures like laser forming are increasingly important, because they make the large-scale-like production of the prototypes with the required materials possible. High accuracy and reproducibility of the products is the precondition of the production. Due to the lack of a forming tool, complex geometries can hardly be manufactured within tolerances. To overcome this problem an automatic closed loop control system for the adjustment of deformations has been developed. An important element of the closed loop control system is the definition of a suitable irradiation strategy for laser forming. For the determination of the irradiation strategy a lot of influences must be taken into consideration from the field of material, geometry and laser. In this paper the improved closed loop control system and the development of an irradiation strategy for 4 mm deep buckles in an ALMgSi1 sheet will be represented. This system can be used e.g. in the automated adjustment of hail damage in car bodies or deformation by heat treatment.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.198.1-198.1
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• 2016

Organic light-emitting diode (OLED) displays have promising potential to replace liquid crystal displays (LCDs) due to their advantages of low power consumption, fast response time, broad viewing angle and flexibility. Organic light emitting materials are vulnerable to moisture and oxygen, so inorganic thin films are required for barrier substrates and encapsulations.[1-2]. In this work, the silicon-based inorganic thin films are deposited on plastic substrates by plasma-enhanced chemical vapor deposition (PECVD) at low temperature. It is necessary to deposit thin film at low temperature. Because the heat gives damage to flexible plastic substrates. As one of the transparent diffusion barrier materials, silicon oxides have been investigated. $SiO_x$ have less toxic, so it is one of the more widely examined materials as a diffusion barrier in addition to the dielectric materials in solid-state electronics [3-4]. The $SiO_x$ thin films are deposited by a PECVD process in low temperature below $100^{\circ}C$. Water vapor transmission rate (WVTR) was determined by a calcium resistance test, and the rate less than $10.^{-2}g/m^2{\cdot}day$ was achieved. And then, flexibility of the film was also evaluated.

• Journal of Power System Engineering
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• v.8 no.3
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• pp.18-22
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• 2004

Boiler is one of the most important utilities providing steam to turbine in order to supply mechanical energy in thermal power plant. It is composed of thousands of tubes for high efficient heat transfer. The material for boiler tubes is used in such high temperature and pressure condition as $540^{\circ}C$, 22MPa. The boiler tube material is required to resist creep damage, fatigue cracking, and corrosion damages. 2.25%Cr-1Mo steel is used for conventional boiler tubes, and austenitenite stainless steel is used for higher temperature boiler tubes. But the temperature and pressure of steam in power plant became higher for high plant efficiency. So, the property of boiler tube material must be upgaded to fit the plant property. Several boiler tube material was developed to fit such conditions. X20CrMoV12.1 steel is also developed in 1980's and used for superheater and reheater tubes in supercritical boilers. The material has martensite microstructures which is difficult to evaluate the degradation. In this thesis, degrade the X20CrMoV12.1 steel at high temperatures in electric furnace, and evaluate hardness with Vickers hardness tester and strengths with Indentation tester.

• Journal of Pharmacopuncture
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• v.8 no.3
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• pp.51-55
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• 2005

Objectives: Literary investigation of existing data was conducted to verify effects of Bezoar Bovis and its herbal acupuncture, and determine quality management through component analysis. Results: Following results were obtained through literary investigation. 1. Bezoar Bovis is dried cystic stone from a cattle. Its characteristics are cool, no toxicity, and bitter taste. Known actions are: quells heat and detoxifies Fire Poison, extinguishes internal movement of Liver Wind and stops convulsion, vaporizes phlegm, and opens orifice. It is mainly used for treating tremor, stroke, delirium, sore throat, oral furuncle, boil, and others. 2. Bezoar Bovis is effective for eliminating liver toxicity, protecting against brain damage, and has anti-microbial activities. 3. Bezoar Bovis is mixed with bear gall bladder and deer musk to be used as herbal acupuncture, and this mixture is effective is invigorating liver functions as well as treating arthritis, headache, and etc. 4. Principal components of Bezoar Bovis are bilirubin-type pigments and cholic acids. The amount of bilirubin can be used as a standard to determine the quality of Bezoar Bovis.

• Proceedings of the KSRS Conference
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• 1999.11a
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• pp.127-131
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• 1999

Typhoons were known by contributing to transporting plus heat or kinetic energy from equatorial region to midlatitude region. Due to the strong damage from typhoon, we acknowledged the theoretical study and the importance of accurate forecast about typhoon. In this study, typhoon forecasting system was developed to search the tracks of past typhoons or to display similar track of past typhoon in comparison with the path of current forecasting typhoon. It was programmed using Interactive Data Language(IDL), which was a complete computing environment for the interactive analysis and visualization of data. Typhoon forecasting system was also included satellite image and auxiliary chart. IR, Water Vapor, Visible satellite images helped users analyze an accurate forecast of typhoon. They were further refined the procedures for generating water vapor winds and gave an initial indication of their utility for numerical weather prediction(NWP), in particular for typhoon track forecasting where they could provide important information. They were also available for its utility in typhoon tracer or intensity.

• Journal of the Korean Society for Precision Engineering
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• v.24 no.12
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• pp.50-56
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• 2007

Femtosecond laser ablation of the Invar alloy and hole drilling for a shadow mask are studied. We used a regenerative amplified Ti-sapphire laser with a 1kHz repetition rate, 184fs pulse duration and 785nm wavelength. Femtosecond laser pulse was irradiated on the Invar alloy with air blowing at the condition of various laser peak power. An ablation characteristic of the Invar alloy was appeared non-linear at $125J/cm^2$ of energy fluence. For the application to a shadow mask, the hole drilling of the Invar alloy with the cross section of a trapezoidal shape was investigated. The ablated micro-holes were characterized using an atomic force microscopy(AFM). The optimal condition of hole pattern f3r a shadow mask was $4\;{\mu}m$ z-axis feed rate, 0.2mm/s circular velocity, $26.4{\mu}J$ laser peak power. With the optimal processing condition, the fine circular hole shape without burr and thermal damage was achieved. Using the femtoseocond laser system, it demonstrates excellent tool for the Invar alloy micro-hole drilling without heat effects and poor edge.

• Journal of Korean Medical classics
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• v.30 no.2
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• pp.99-112
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• 2017

Objectives : 28 prescriptions with the name 'Dossi' can be found in Yixuerumen, and all these prescriptions are highly useful due to their clinical effectiveness. Among them, Dossisosihotang has an important role as the essential prescription utilizing harmonizing and releasing formula. Therefore, this paper aims to ponder upon this prescription. Methods : Dossisosihotang's origin and effectiveness were studied, and the findings served as the basis for analyzing the varied forms of this prescription which came about in the later generations in order to consider more detailed usage of this prescription. Results & Conclusions : Dossisosihotang directs its patient to consume sosihotang added with chenpi, shaoyao, chuanxiong, then simmered, and added with three spoons worth of raw wormwood juice. Its origin can be traced back to shachechuifa's 'Sihossanghaeeum,' and it is mainly effective for treating the blood aspect syndrome of lesser yang disease such as women's cold damage and heat entering the blood chamber. In treating the symptom of half-exterior and half-interior, taohua developed prescriptions depending on the syndrome, such as Sihijigyungtang, Sihohamhyoungtang, Samhosambacktang, Siryungtang, Sihosamultang, Sigalhaegitang, and Samhoseoggotang. These prescriptions became widely known for their clinical efficacy, leading to many later generations of clinical doctors to use them.

• Journal of the Korean Society of Safety
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• v.31 no.5
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• pp.54-60
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• 2016

In this study, tank truck incidents of road transport of hazardous materials to experimental investigated the potential fire hazard. Real scale fire was to perform experiments for on this qualitative and quantitative data collection and analysis. Particularly affected by radiant heat from the flames caused and damage estimates range investigated accordingly. Flame temperature, internal temperature of tank and emitted radiation from the flames was investigated. The flame of light oil spill caused a fire at a temperature of about $300^{\circ}C$ high in comparison with the methanol by combustion of diesel and methanol, according to the difference, the flame duration changes varies depending on the Burning rate. Depending on spill rate(30, 60, 90 and $120{\ell}/min$) and the longer the duration of the flame important factors for the internal temperature of tank lorry rise was found. Road accident in a fire caused by leakage of hazardous was could the higher the damaged. Therefor, Fire suppression activities should be required in particular to be around.

• The Journal of Korean Medicine
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• v.28 no.3 s.71
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• pp.232-243
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• 2007

Objective : This study researched the application of Sa-am acupuncture for the treatment of hiccup. Methods : We investigated the literature for Sa-am acupuncture treatment and traditional acupuncture treatment for hiccup. Result & Conclusion : In traditional oriental medicine, hiccup is considered to be caused by uprising stomach gi, whereas, in Sa-am acupuncture, it is considered to be caused by weakness and impurity of lung gi. In Sa-am acupuncture, hiccup is divided into five classes; reverse hiccup (treated with large intestine tonification), wind hiccup (treated with liver tonification), fire hiccup (treated with heart tonification), damp hiccup (treated with spleen tonification) and cold hiccup (treated with kidney tonification). In traditional oriental medicine, hiccup is treated by way of lowering the uprising stomach gi, while, in Sa-am acupuncture, hiccup is treated by way of removing whichever of the original cause of hiccups (impurity of large intestine, damage to liver, dry heat of heart, impairment of spleen, exhaustion of kidney) caused the weakness and the impurity of lung gi. In Sa-am acupuncture, the therapeutic mode for all the five causes of hiccups is tonification mode.