• Metals and materials international
• /
• v.24 no.6
• /
• pp.1327-1332
• /
• 2018

In this study, a novel approach to the explosive synthesis of titanium carbide (TiC) is discussed. Nonstoichiometric $TiC_x$ powder was produced via the underwater explosion of a Ti powder encapsulated within a spherical explosive charge. The explosion process, bubble formation, and synthesis process were visualized using high-speed camera imaging. It was concluded that synthesis occurred within the detonation gas during the first expansion/contraction cycle of the bubble, which was accompanied by a strong emission of light. The recovered powders were studied using scanning electron microscopy and X-ray diffraction. Submicron particles were generated during the explosion. An increase in the carbon content of the starting powder resulted in an increase in the carbon content of the final product. No oxide byproducts were observed within the recovered powders.

• Journal of Advanced Marine Engineering and Technology
• /
• v.10 no.3
• /
• pp.1-10
• /
• 1986

This paper describes a new, effective method developed at the National Research Council Canada for rolling element bearing incipient failure detection. This method can detect not only outer race damage, previously published, but also inner race damage with a 100% detection rate based on a sample size of 32. The prediction of the exact angular location of the damage spot along the raceway is illustrated and experimental confirmation is presented. For the first time, a statically measurable parameter for inner and outer race damage is introduced as a means of verifying other techniques which do not offer absolute proof, but resort only to "overwhelming evidence". A brief comparison with other methods such as Shock Pulse Method, Kurtosis Analysis and High Frequency Resonance Technique is presented. A computerized automatic monitoring system utilizing the new method is described and experimental results are presented.presented.

• The Journal of the Acoustical Society of Korea
• /
• v.38 no.4
• /
• pp.459-466
• /
• 2019

When a laser pulse is irradiated on a CNT (Carbon Nanotube) and PDMS (Poly dimethylsiloxane) composite coated on a transparent PMMA (Poly methyl methacrylate) substrate, a strong ultrasonic wave is generated due to the thermoelastic effect. In this paper, the thermoacoustic theory related to the wave generation by the CNT/PDMS composite was established. The waveforms of ultrasonic waves when a laser pulse having a Gaussian waveform is irradiated on the composite with a thickness of $20{\mu}m$ were numerically simulated. From the results, it was confirmed that ultrasonic shock waves can be generated from the CNT/PDMS composite and the waveforms are changed little even if the physical properties of the composite are changed by ${\pm}20%$. It was found that the peak positive and negative pressures increase as the thermal expansion coefficient increases, or as density, heat capacity and sound speed decreased. However, those changes were not so sensitive with thermal conductivity. In addition, the physical properties of the CNT/PDMS composite fabricated in this study were estimated from the comparison of the measurement and simulation results.

• Journal of the Korean Chemical Society
• /
• v.23 no.3
• /
• pp.132-135
• /
• 1979

The thermal decomposition of a dilute mixture of 1,1,2,2,-$C_2H_2F_4$ in argon has been investigated in a single-pulse shock tube between 1146 and $1232^{\circ}K$ at total reflected shock pressures of about 3000 torr. Under these conditions the reaction proceeds exclusively by the molecular elimination of hydrogen fluoride. It has been found that the asymmetric isomer with the fully fluorinated ${\alpha}$-carbon requires the higher activation energy which may be attributed to the difference in atomic charge densities between isomers. The rate constant ratio is given by $log(k_1/k_2) = -0.069 {\pm} 0.021 ＋(1388{\pm}113) / 2.303RT$ in good agreement with previous independent studies.

• Tuberculosis and Respiratory Diseases
• /
• v.44 no.6
• /
• pp.1382-1389
• /
• 1997

Hantavirus pulmonary syndrome(HPS) is a systemic disease that is caused by a newly discorved and characterized virus of the Hantavirus genus, which is most frequently referred to as the sin nombre virus. The clinical syndrome resembles other hantavirus syndromes worldwide, except that it is characterized by a brief prodromal illness followed by rapidly progressive, noncardiogenic edema, and that it is more deadly than any previously recognized hantavirus infection. The clinical manifestations of HPS are characterized by four clinical phases : prodrome, pulmonary edema and shock, diuresis, and convalescence. Mortality is greatest in the first 24 hours of the pulmonary edema and shock phase of the illness. These phases are strikingly similar to the clinical phases of Hemorrhagic fever with renal syndrome(HFRS) induced by Hantaan virus, except that HPS has not been associated with renal failure and Disseminated intravascular coagulation(DIC). We here report a case of hantavirus pulmonary syndrome developed in a 58 year-old man. He had a flu-like illness followed by the rapid onset of respiratory failure due to noncardiogenic pulmonary edema. HPS was diagnosed by clinical manifestations, identification of high titer antibody to Hantaan virus antigen and histologic finding of transbronchial lung biopsy (TBLB) specimen. The patient was treated with mechanical ventilation and initial corticosteroid pulse therapy resulting in successful outcome.

• Journal of the Korea Computer Industry Society
• /
• v.8 no.1
• /
• pp.49-56
• /
• 2007

Various kind of laser had been used on addition to endoscope for obstetrics and gynecology, gas laser such as CO2 laser had been used mainly much in laparoscope surgical operation mainly Thermal effect of beam displays other result different component parts of cellular tissue and different close of a marketplace of laser beam and priority solidification of temperature increase consists in cellular tissue, and cutting or carbonization process happens and evaporation by breakdown of cellular tissue happens more than $300^{\circ}$. <중략> Ostabilization of pulse transformer by high tension output module of CO2analog laser for obstetrics and gynecology that accomplish marks of honor kind switching and accuracy is required, and stabilize with laser output applying Turn-off in existent hard switching forward converter, on city happened switching damage, damage increase of output diode station recovery special quality, parasitism shock, design and result that manufacture, brought result that improve than existing product. Will be bought to get into superior result if supplement as systematic late.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.42 no.10
• /
• pp.858-869
• /
• 2014

Most of the aerospace propulsion is based on the Brayton cycle, in which the combustion is held through the constant pressure process, but further improvement of performance by increasing compression ratio is challenged by mechanical limits. Detonation propulsions, regarded promising for high-speed propulsion for a lase decade, is more rigorously studied in these days as a game-changer for the improvement of thermodynamic efficiency of propulsion and power generation systems. Since, the additional compression by the strong shock of the detonation wave is considered increasing thermodynamics efficiency that is hardly achievable by the conventional compression systems. Present paper will give an introduction the latest technical trends on the Pulse Detonation Engines(PDEs) and the activities on the Pressure Gain Combustion (PGC) based on Constant Volume Combustion (CVC).

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.35 no.2
• /
• pp.47-55
• /
• 2021

In order to ensure the fact that eight principle pattern differentiation is used clinically as a basic guideline for Korean medicine practice, the definition, role and method of yin-yang pattern differentiation with its case report were explored at first. Yinyang Pattern Differentiation is a method of discriminating human tendencies or morbidity based on the yin and yang characteristics expressed in living bodies. And yin and yang are the two contrasting characteristics and aspects of the interaction when certain physical conditions that have a lasting effect on the human physiological metabolic function are correlated with the morbidity. Specific methods of yinyang pattern differentiation can be divided into several types of yin and yang indicators. First, time and space factors like day and night, hot and cold seasons, above and below, topographical districts. Second, colors and pulse and their/or relative clearness and muddiness, hardness and softness, moving and resting. Third, diagnose yin and yang patterns through distinguishing the true and false of a fever and cold in an emergency phase such as increase of brain pressure and shock state. Fourth, general characteristics of the propensity and constitution of a subject such as body type, speech, behavior, and physiological metabolism. And for clinical use, these were summarized again as a symptom indicators of physical signs and color, pulse, tongue and questionnaire indicators of propensity, body type, and space-time characteristics. Conclusively, it was confirmed that yinyang pattern differentiation has its own diagnostic significance which is distinct from exterior-interior, cold-heat and deficiency-excess pattern differentiation.

• International Journal of Aerospace System Engineering
• /
• v.9 no.2
• /
• pp.1-9
• /
• 2022

The NEA release mechanism is used to provide restraint and release functions with low shock for critical deployment operations on solar arrays after launch. The GK3 solar array consists of 2 wings and 6 hold down points per panel. The NEA SSD9103S1 is a part of the GK3 solar array hold-down and release mechanism. Each NEA unit is equipped with two Z-diodes which provide power to a NEA unit connected in series after actuation of the fuse wire. This paper presents the hot firing test results of a quadrature NEA SSD9103S1 configuration. One output powers a maximum of 4 NEA SSD9103S1 units simultaneously. The necessary actuation pulse duration has been determined to meet margin requirement for thermal energy of minimum 4. Actuation thermal energy difference is about 6.6% between each half of two fired serial NEAs. Thermal energy margin at worst case is minimum 5.9 in case of an actuation pulse duration of 500 ms. Two series Zener impedance depend on current applied has been characterized by an additional actuation after all fuse wires are open circuit. Total number of actuation commands to the GK3 NEA unit reduce drastically from 24 in case of single NEA configuration down to 8 in case of parallel and quadrature NEA configurations. It can be accommodated by the existing HP2U Pyro design without any impact.

• Asian Pacific Journal of Cancer Prevention
• /
• v.15 no.20
• /
• pp.8947-8950
• /
• 2014

Immunological functions of heat shock proteins (HSPs) have long been recognized. In this study we aimed to efficiently purify HSP70 from renal cell carcinoma and test it as a tumor antigen for pulsing dendritic cells in vitro. HSP70 was purified from renal cell carcinoma specimens by serial column chromatography on Con A-sepharose, PD-10, ADP-agarose and DEAE-cellulose, and finally subjected to fast protein liquid chromatography (FPLC). Dendritic cells derived from the adherent fraction of peripheral blood mononuclear cells were cultured in the presence of IL-4 and GM-CSF and exposed to tumor HSP70. After 24 hours, dendritic cells were phenotypically characterized by flow cytometry. T cells obtained from the non-adherent fraction of peripheral blood mononuclear cells were then co-cultured with HSP70-pulsed dendritic cells and after 3 days T cell cytotoxicity towards primary cultured renal cell carcinoma cells was examined by Cell Counting Kit-8 assay. Dendritic cells pulsed in vitro with tumor-derived HSP70 expressed higher levels of CD83, CD80, CD86 and HLA-DR maturation markers than those pulsed with tumor cell lysate and comparable to that of dendritic cells pulsed with tumor cell lysate plus TNF-${\alpha}$. Concomitantly, cytotoxic T-lymphocytes induced by HSP70-pulsed dendritic cells presented the highest cytotoxic activity. There were no significant differences when using homologous or autologous HSP70 as the tumor antigen. HSP70 can be efficiently purified by chromatography and induces in vitro dendritic cell maturation in the absence of TNF-${\alpha}$. Conspecific HSP70 may effectively be used as a tumor antigen to pulse dendritic cells in vitro.