• Journal of Korea Foundry Society
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• v.6 no.4
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• pp.290-297
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• 1986

Austempered ductile cast iron has been well known for their good toughness and strength. Generally these properties were improved by the various heat treatments and alloying elements. In this study, the effects of prior heat treatment history(near ferrite, near pearlite, near martensite) on the toughness and strength of the austempered ductile cast iron were studied experimentally and theoretically. All of the test specimens was austenitized at $900^{\circ}C$ for 1 h and austempered at $300^{\circ}C$, $350^{\circ}C$, $400^{\circ}C$, $450^{\circ}C$, respectively. The prior structure of near martensite in austempered ductile cast iron was not good in term of toughness and strength because the carbon content was apt to high in austenite during ausnitizing. It was found, on the other hand, that the ferrite matrix as prior structure had good combination of toughness and strenght. The best tensile strength and good toughness were obtained at $300^{\circ}C$, austemper in the prior structure of near ferrite, while $400^{\circ}C$ austemper in that of near pearlite and martensite.

• Proceedings of the KIEE Conference
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• 1993.07b
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• pp.1174-1176
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• 1993

Morphology of low density polyethylene(LDPE) such as the degree of crystallinity changes with thermal history etc. In order to clarify the effects of morphological changes on electrical breakdown, we studied direct current and impulse breakdown phenomena of LDPE films heat-treated at 100[$^{\circ}C$] for 1[H] in silicone oil and subsequently cooling to various ways. The degree of crystallinity was estimated by the infra red absorption and X-ray diffraction measurements for the specimens of slowly cooled, cooled in water, original, and cooled in liquid nitrogen gas. As the result, we obtained that the first, second, third, and fourth was slowly cooled of 70.23[%], cooled in water of 61.6[%], original specimen of 56.75[%], and cooled in liquid nitrogen gas of 34.7[%] respectively. The crystalline size and distribution of specimens were researched by Differential scanning calolimeter measurements.

• Corrosion Science and Technology
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• v.11 no.5
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• pp.196-204
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• 2012

Corrosion failure of petrochemical facilities is one of the difficulties in maintenance, since operating conditions of crude oil production, storage, and refinement are very aggressive. UNS N08810, which has been used for crude oil transportation pipes and storage tanks in petrochemical industries, shows good resistance to general corrosion and localized corrosion in several environments. Among its environments, UNS N08810 showed better corrosion resistance in fuel gas containing sulfuric acid and phosphoric acid and sulfur. However, ductility and toughness at high temperature over about $500^{\circ}C$ were greatly reduced due to microstructural change. In general, welding process is the representative method to join the parts in industrial components. Because the alloy by welding can be sensitized and corroded, the manufacturing process should be controlled. In this work, UNS N08810 was used and heat treatment conditions including solution and stabilization treatments were controlled. Oxalic acid etch test by ASTM A262 Practice A was done to evaluate the qualitative sensitization in room temperature. Huey test by ASTM A262 Practice C was done to evaluate the intergranular corrosion rate in boiling 65% $HNO_3$ solution. Also, the microstructure by thermal history was analyzed. Experimental alloy showed high intergranular corrosion rate and its corrosion mechanism was elucidated.

• Restorative Dentistry and Endodontics
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• v.20 no.1
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• pp.235-249
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• 1995

This study was designed to identify the lymphocytes present and to examine the relation between lymphocytes population and clinical symptoms of the pulps clinically diagnosed as normal and irreversible pulpitis. We recorded the history and severity of the pain and performed several clinical tests, before extirpation of vital, irreversibly inflamed pulps in routine endodontic treatment. Then the teeth were divided into two groups. Five teeth, categorized in acute symptom group, had severe spontaneous pain, particularly at night and were extremely sensitive to cold and heat. The other 15 teeth with history of mild to moderate pain and with or without cold or heat responses were categorized as chronic symptom group. Inflamed pulps were also classified into 8 minor groups by presence or absence of signs or symptoms related to the involved teeth, including the presence of pain on percussion, pain on heat and cold stimuli and the periodontal pocket depth. All extirpated pulps were immediately immersed in ultra low-temperature freezer($-74^{\circ}C$), and they were sectioned $6{\mu}m$ in thickness. Specimens were stained using three-stage indirect immunoperoxidase techniques(DAKO, LSAB kit) and monoclonal antibodies for detecting the presence of T lymphocytes(T), B lymphocytes(B) and helper(T4) and suppressor(T8) lymphocytes. Following results were obtained; 1. All the examined normal and inflamed pull) tissues had positive staining for T lymphocytes and T helper and T suppressor cells. But B cells were observed only in inflamed pulp. 2. Statistically more T and B cells were observed in acute symptom group as compared with chronic symptom group(p<0.05). 3. Cell ratio of BIT in acute symptom group were significantly higher than that of chronic symptom group(p<0.05). 4. Only B cells were significantly increased in the percussion positive group than the number of B cells in percussion negative group(p<0.05). 5. No differences were observed in the number of different cell types among other minor groups.

• Korean Journal of Veterinary Research
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• v.63 no.2
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• pp.20.1-20.4
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• 2023

A 10-year-old, spayed female, Maltese dog presented with a 2-day history of severe left eye squint. Slit-lamp biomicroscopy showed a deep corneal defect stained into a doughnut shape together with hypopyon in the anterior chamber. Based on these results, a diagnosis of descemetocele and uveitis in the left eye was made. Deep keratotomy combined with a nictitating membrane flap effectively resolved the descemetocele without complications. The surgical procedures performed on this patient were easy and effective, and could be used as an alternative to graft surgery for descemetocele treatment.

• Journal of Korean Medical classics
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• v.21 no.4
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• pp.179-191
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• 2008

Yuchang(喩昌), prominent doctor in the early days of Cheong Dynasty, argued in favor of Daegiron(大氣論) and Chujoron(秋燥論). He referred the concept of Daegi(大氣) to the initiatory force that maintains and perpetuates the vital activities of human body. The historical background of his argument can be related to the abuses of the doctrine of warming and tonifying. At that time, the practice of misusing warming and tonifying herbal medicines without deteriorations of a case was widespread among doctors. Dryness and heat disease mechanism was triggered from this malpractice. Subsequently Yuchang(喩昌) witnessed many cases of lung diseases resulting from dryness and heat. That's why he suggested relieving dryness of the lung as a treatment, further establishing Daegi(大氣) - which correlates with the lung - as the vital fundamentals. Yuchang(喩昌)'s argues that the autumn energy emanates after the Autumn Equinox and that is what Chujo(秋燥) signifies in Chujoron(秋燥論). He articulates that most of the autumn diseases can be attributed to fire and heat. This argument is distinguished from the one that attributes lung diseases to coldness, thus providing an important factor in deteriorating a lung disease.

• The Journal of Korean Obstetrics and Gynecology
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• v.19 no.2
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• pp.295-304
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• 2006

Inflammatory conditions of the breast are uncommon and may be encountered in the puerperal and nonpuerperal setting. Nonpuerperal mastitis is less common and usually presents with inflammation and chronic abscess formation in the periareolar and peripheral region. These abscess have a high rate of recurrence and are often associated with an underlying disease state, such as diabetes, steroid treatment, trauma or other kinds of a deficient immune system. The diagnosis is suggested by the history of sudden onset and the presense of swelling, tenderness, heat, erythema, and in the case of abscess, fluctuation. Ultrasound can also be useful. Treatment consists of antibiotic administration or incision and drainage of the abscess and, in cases of retroareolar abscess, resection of entire underlying duct system. Recently, we have gotten good result from treating two cases of nonpuerperal mastitis and breast abscess which had treatment of antibiotics and drainage three times but recurred. After taking gamijipaesan(加味芷貝散) and acupuncture treatment, they have recovered and haven't recurred in 8 months. So it proves that herb medication and acupuncture are effective on nonpuerperal chronic mastitis and breast abscess.

• Journal of Ginseng Research
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• v.37 no.4
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• pp.379-388
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• 2013

Diabetic nephropathy is one of the serious complications in patients with either type 1 or 2 diabetes mellitus but current treatments remain unsatisfactory. Results of clinical research studies demonstrate that Panax ginseng can help adjust blood pressure and reduce blood sugar and may be advantageous in the treatment of tuberculosis and kidney damage in people with diabetes. The heat-processing method to strengthen the efficacy of P. ginseng has been well-defined based on a long history of ethnopharmacological evidence. The protective effects of P. ginseng on pathological conditions and renal damage associated with diabetic nephropathy in the animal models were markedly improved by heat-processing. The concentrations of less-polar ginsenosides (20(S)-Rg3, 20(R)-Rg3, Rg5, and Rk1) and maltol in P. ginseng were significantly increased in a heat-processing temperature-dependent manner. Based on researches in animal models of diabetes, ginsenoside 20(S)-Rg3 and maltol were evaluated to have therapeutic potential against diabetic renal damage. These effects were achieved through the inhibition of inflammatory pathway activated by oxidative stress and advanced glycation endproducts. These findings indicate that ginsenoside 20(S)-Rg3 and maltol are important bioactive constituents of heat-processed ginseng in the control of pathological conditions associated with diabetic nephropathy.

• Journal of Korean Medical classics
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• v.33 no.1
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• pp.149-158
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• 2020

Objectives : This study aims to examine the exterior relief method through pungent-cool properties in comparison to pungent-warm properties historically, to understand the meaning of 'exterior relief through pungent-cool' more thoroughly. Methods : Contents mentioning the treatment method directly were examined historically, then analyzed. Results & Conclusions : The method to relieve the exterior through pungent-cool properties has developed by overcoming the limitations of the method to relieve the exterior through pungent-warm properties since it was first established in 『Shanghanzabinglun』(『傷寒雜病論』). The term 'relief of the exterior through pungent-coolness'(辛凉解表) was first mentioned in the Ming period, referring to weak level of perspiration. Yetianshi(葉天士) explained it as communicating Weiqi(衛氣) using pungent-cool medicinals for heat to discharge through the exterior, resulting in mild sweating. In 『Wenbingtiaobian』(『溫病條辨』) the term 'to relieve the flesh'(解肌) refers to both mild sweating through pungent-warm medicinals and the opening of the exterior through pungent-cool medicinals for pathogenic qi to exit, resulting in sweating. If the exterior relief of the pungent-warm medicinals happens through the warm Yang qi(陽氣) stimulated the inner Yin fluids(陰液) to discharge as sweat, that through pungent-cool medicinals relieves stagnation in the exterior, opening up a way for the pathogenic heat to exit. From the perspective of the main therapeutic mechanism for pungent-cool medicinals to be its coolness relieving heat, the term 'exterior relief through pungent-coolness' becomes erroneous. For the 'exterior relief through pungent-coolness' category to be valid, the meaning of 'exterior relief' needs to be expanded to include not only stimulated sweating but the treatment process that could result in sweating.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.17 no.2
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• pp.81-86
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• 2004

Objective: This study was designed to investigate clinical features of chronic urticaria and assess Korean traditional medical therapy on that. Methods: The ratio of male and female, duration of symptoms, personal history and family history of allergic diseases, serum IgE level, and suspected causes and provocation factors were investigated in 41 patients with chronic urticaria. And frequency of wheals, duration of wheals, number of wheals, itch severity, and antihistamine counts of 6-point(0-5) score was assessed in 26 patients. The change of total scores between baseline and follow up were analyzed using Wilcoxon signed-rank test(p〈0.05). Results: 1. The ratio of male and female was 1:1.28 and the mean duration of symptoms was 26.0 months. 2. The frequency of personal history and family history of allergic diseases was each 53.7$\%$ and 48.8$\%$ and 30.6$\%$ had over 200 IU／mL serum IgE level. 3. The suspected causes were none(43.9$\%$), foods(29.3$\%$), drugs(9.8$\%$) and stress(7.3$\%$). 4. The suspected provocation factors were foods(39.0$\%$), none(19.5$\%$), fatigue(17.0$\%$), heat and sweating(l4.6$\%$), pressure(12.2$\%$) and stress(9.8). 5. The total scores between baseline and follow up of 26 patients was lowered from 14.85${\pm}$3.80 to 7.65${\pm}$4.31 and it was significant statistically. Conclusions: Korean traditional medical therapy was proved to be effective on the chronic urticaria and we need to consider foods as important factor in both treatment and patient education of urticaria.