• 한국세라믹학회지
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• 제19권2호
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• pp.121-126
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• 1982

This paper deals with the $Si_3N_4$-bonded SiC refractory in terms of its microstructure development during nitridation. When mixture of SiC grains and fine Si power is fired under nitrogen atmosphere, an interlocking network of $Si_3N_4$ whiskers is formed by nitridation of Si. It is found that the strength of $Si_3N_4$-bonded SiC refractory is soley due to the physical nature of this interlocking whiskers. At the initial stage of nitridation, $Si_3N_4$ whisker forms in very thin and long shape and, with further nitridation, it becomes thicker with diameters up to 0.35$\mu\textrm{m}$. It is found that the mechanical strength of $Si_3N_4$-bonded SiC refractory depends on the degree of nitridation and the development of microstructure.

• 대한기계학회논문집A
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• 제26권3호
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• pp.445-451
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• 2002

The refractory-lined pipe is used to protect the system from high-temperature of the internal flow. The property of the refractory has an effect upon the stress analysis for fluid catalytic cracking(FCC) unit piping design. The equivalent elastic modulus and density considering steel and refractory must be applied in the stress analysis of the system. In the research, the theoretical method to obtain the value of the equivalent property is introduced and then the parametric analysis is carried out to understand the characteristic of the material properties, and the stress analysis is performed with reactor, the part of FCC unit.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2000년도 추계학술대회 논문집
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• pp.547-550
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• 2000

The steel pipe for fluid catalytic cracking(FCC) unit. petroleum refinery, is lined with refractory to protect the system from high-temperature of the internal flow. The property of the refractory has an effect upon the stress analysis of FCC unit. Because 1-D pipe element or 3-D shell element are usually used in commercial codes of stress analysis to evaluate the structural soundness, the equivalent elastic modulus considering steel and refractory should be applied. In the research, the theoretical method to obtain the value of the equivalent property is introduced and then the stress analysis is carried out with the part of FCC unit.

• Asian Pacific Journal of Cancer Prevention
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• 제15권4호
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• pp.1885-1887
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• 2014

Skin metastases of breast cancer are usually late events in the course of tumor progression and signify a poor prognosis. They may remain as a therapeutic challenge especially after failure of standard treatments. Topical interventions, together with or without radiotherapy, may only palliate the symptoms temporarily. However, there may be alternative treatment modalities for unresectable breast cancer skin metastases resistant to chemotherapy and radiotherapy. There are various genetic alterations in tumors and therapeutic potential of expression patterns for factors like epidermal growth factor receptor may have important clinical implications in case of disease refractory to the conventional treatments. Here, we clarified the therapeutic options and genetic alterations in skin metastatic breast cancer patients refractory to standard chemotherapeutics.

• 한국세라믹학회지
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• 제17권3호
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• pp.145-150
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• 1980

This paper deals with the clay-bonded silicon carbide refractory saggars in terms of its oxidation resistance. Oxidation is one of the major causes of failure in silicon carbide refractory saggars during its services. Various anti-oxidation additives are coated on or added into silicon carbide refractories and their effects are studied while other conditions are equal. Several conclusions can be derived for optimum anti-oxidation additive as: 1. The additive should wet each silicon carbide grain completely during its firing. 2. The additive should have high viscosity at temperatures around $1, 350^{\circ}C$ where most silicon carbide refractory saggars are being used. 3. The additive should have ability to absorb or desorb oxygen depending on the local atmosphere inside of saggar during it service. 4. The addition should be kept as minimum as possible to prevent any "sweating" or "bloating" phenomena.ing" phenomena.mena.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집A
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• pp.964-968
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• 2001

The refractory-lined pipe is used to protect the system from high-temperature of the internal flow. The property of the refractory has an effect upon the stress analysis for fluid catalyst cracking(FCC) unit piping design. The equivalent elastic modulus and density considering steel and refractory must be applied in the stress analysis of the system. In the research, the theoretical method to obtain the value of the equivalent property is introduced and then the parametric analysis is carried out to understand the characteristic of the material properties.

• International journal of thyroidology
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• 제11권2호
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• pp.75-77
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• 2018

Tyrosine kinase inhibitor is known to prolong progression free survival in radioiodine refractory thyroid cancer patients. Fatigue/asthenia/malaise is one of most common adverse events by the tyrosine kinase inhibitor treatment, and management of the adverse event is important to keep the drug medication longer which is essential for the survival benefit. In the case report, a radioiodine refractory thyroid cancer patient receiving tyrosine kinase inhibitor experienced severe fatigue, and a pathologic fracture of right humerus occurred by slipping down which was tightly linked with the adverse event of the drug. The pathologic fracture was surgically well managed and the adverse event was well controlled by supportive managements combined with dose reduction of the tyrosine kinase inhibitor. The drug administration to the patient was kept more than 1 year without progression of the disease.

• Clinical and Experimental Reproductive Medicine
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• 제49권3호
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• pp.168-174
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• 2022

Refractory thin endometrium and recurrent implantation failure are among the most challenging infertility-related factors hindering successful pregnancy. Several adjuvant therapies have been investigated to increase endometrial thickness and the pregnancy rate, but the treatment effect is still minimal, and for many patients, these treatment methods can be quite costly and difficult to approach. Platelet-rich plasma (PRP) is an autologous concentration of platelets in plasma and has recently been elucidated as a better treatment option for these patients. PRP is rich in cytokines and growth factors, which are suggested to exert a regenerative effect at the level of the injured tissue. Another advantage of PRP is that it is easily obtained from the patient's own blood. We aimed to review the recent findings of PRP therapy used for patients with refractory thin endometrium and recurrent implantation failure.

• The Korean Journal of Ceramics
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• 제4권4호
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• pp.279-285
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• 1998

The $UO_2$ pellets are usually sintered under hydrogen gas atmosphere. Hydrogen gas may cause unexpected early failure of the refractory bricks in the sintering furnace. In this work, nitrogen was mixed with hydrogen to investigate the effect of nitrogen gas on a failure machanism of the refractory bricks and on the microstructure of the $UO_2$ pellet. The hydrogen-nitrogen mixed gas experiments show that the larger nitrogen the mixed gas contains, the less the refractory materials are reduced by hydrogen. The weight loss measurements at $1400^{\circ}C$ for fire clay and chamotte refractories containing high content of $SiO_2$ indicate that the weight loss rate for the mixed gas is about half of that for the hydrogen gas. Based on the thermochemical analyses, it is proposed that the weight loss is caused by hydrogen-induced reduction of free $SiO_2$ and/or $SiO_2$ bonded to $Al_2O_3$ in the fire clay and chamotte refractories. However, the retardation of the hydrogen-induced $SiO_2$ reduction rate under the mixed gas atmosphere may be due to the reduction of the surface reaction rate between hydrogen gas and refractory materials in proportion to volume fraction of nitrogen gas in the mixed gas. On the other hand, the mixed gas experiments show that the test data for $UO_2$ pellet still meet the related specification values, even if there exists a slight difference in the pellet microstructural parameters between the cases of the mixed gas and the hydrogen gas.

• 전자공학회논문지
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• 제50권5호
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• pp.242-250
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• 2013

본 논문에서는 심장의 심근세포의 탈분극과 재분극을 반영하는 불응기(Refractory Period)를 이용한 R-파 검출 알고리즘을 제안한다. 제안 알고리즘은 R-파의 특징과 가변 불응기를 이용하여 R-정점을 검출한다. 먼저 상대적으로 높은 전위 점을 R-정점 후보로 추출하고, 그 후보 점에 대해 첨도와 전위를 고려한 불응기를 구한다. 다음으로 불응기내에서 R-파의 형태학적 특징을 이용하여 R-정점을 검출한다. 제안 알고리즘은 적은 연산을 가지므로 실시간 처리가 가능하다. 제안한 알고리즘을 MIT-BIH 부정맥 데이터베이스의 모든 레코드에 적용한 결과 99.7% 이상의 매우 우수한 검출율을 보였다.