• 한국환경과학회지
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• 제9권5호
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• pp.423-428
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• 2000

The characteristics of Far-infrared rays mineral water(FIR water) have been compared to the tap water by means of relationship between FIR water and Nuclear Magnetic Resonance spectroscopy(NMR), FIR water and thermography FIR water and velocity of blood FIR-water and pH, FIR water and dissolved oxygen(DO), FIR water and Oxidation-Reduction Potential(ORP) using the development FIR water purification of grand prix system. From the experimental result are quite satisfactory when compared with the tap water. Also the FIR water were evaluated to see if those are tasty and healthy using the Hashimoto's Mineral Balance Index. As a result FIR-water was found as tasty and healthy.

• 한국가구학회지
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• 제18권2호
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• pp.100-105
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• 2007

In this report, we describe the anatomical features of Gmelina arborea Roxb. belong to the genera of Verbenaceae native to Bangladesh and safranine penetration depth in radial and longitudinal directions. The wood of this species was characterized mostly by distinct growth ring boundaries, diffuse-porous, simple perforations, alternate non-vestured intervessel pits, and relatively short vessel elements and medium fibers. Thin to thick walled septate fibers with simple to minutely bordered pits are confined to the radial walls. Tyloses are common. They are paratracheal axial parenchyma vascicnetric and confluent. Rays not higher than 1milimeter are found, and larger rays commonly 4 to 5 seriate are dominantly present, as are multi seriate rays composed of a procumbent ray with 1 row of square or upright cells. Acicular crystals are present in ray cells. Another experiment was taken under consideration to observe the liquid penetration depth in longitudinal and radial directions using safranine. It was found that safranine penetrated easily in longitudinal direction and sapwood was more permeable than heartwood.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제48권2호
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• pp.86-91
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• 1999

In order to analyse the degradation process of epoxy/glass fiber for outdoor condition, FRP laminate was exposed to the wavelength of ultraviolet rays and evaluated by comparing contact angle, surface resistivity, surface potential decay, and ESCA spectrum respectively. As irradiation energy are increased, the surface properties were steeply decreased in the range of 300[nm]. But the measured values within the scope of400[nm]∼440[nm] showed a increase as compared with the untreated ones. Also, fromthe result of ESCA spectrum, it was confirmed plenty of oxygen groups on the spot showing the maximum decrease of surface properties and the existence of ether groups on the surface of coloring phase. We can conclude that the degradation phenomena on the surface of epoxy composites are dominated by the induction of ester and carboxyl groups.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2009년도 춘계학술발표대회 논문집
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• pp.3-7
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• 2009

The amount of incident rays over inclination according to direction has been widely utilized as important data in installing solar thermal systems. To optimize the incident solar radiation, the slope, that is the angle between the plane surface in question and the horizontal, and the solar azimuth angles are needed for these solar thermal systems. This is because the performance of the solar thermal systems in much affected by angle and direction of incident rays. Recognizing that factors mentioned above are of importance, actual experiment on the moving route of the sun have been performed in this research to obtain the angle of inclination with which the maximum incident rays can be absorbed. After all, the standard for designing highly optimized solar thermal systems will be provided for designers and employees working in the solar collector related industries.

• Nuclear Engineering and Technology
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• 제4권3호
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• pp.223-228
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• 1972

Radiography에 있어서 피사체로부터의 산란 ${\gamma}$선은 film상의 상질을 나쁘게 하는 큰 요소중에 하나이다. 피사체로부터의 산란선량을 조사하기 위하여 여러가지 폭의 slit에 의한 조사장에서의 film의 흑화농도를 구했다. 또 그때의 투과측정기 검출감도의 양부도 검토했다. 피사체가 두꺼워지면 산란선량이 증가하여 결함검출도가 저하하지만, slit폭을 좁힘으로써 개선할 수가 있었다. 그러고 선원은 $_{60}$Co을 사용했고 시료는 철로서 실험을 했다.

• Nuclear Engineering and Technology
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• 제52권8호
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• pp.1792-1797
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• 2020

The shielding characteristics of two concrete blocks, widely used in the building industry in Mexico have been determined. These characteristics include the mass interaction coefficients, the linear attenuation coefficients and the half-value layers. The energy-dispersed X-ray fluorescence shows that the percentage mass content of each atom in the sample, and the atomic volume of the constituent elements of a material, plays an important role in its shielding capabilities. The total linear attenuation coefficients and the half-value layers were analyzed for a set of photon energies related to X-rays for diagnosis and cancer treatment with linear accelerators. Our results show that the concrete blocks have similar photon attenuation coefficients than the Portland concrete and better features than gypsum.

• 천문학회지
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• 제29권spc1호
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• pp.291-294
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• 1996

The .Japanese sun observing satellite, Yohkoh, has been operational for five years and her scientific instruments are still in good condition. They have revealed ample of evidences that solar flares were triggered by magnetic reconnection, which was, for the first time, clearly indicated to take place in the solar corona. Cusp structures in soft X-rays and a new type of hard X-ray sources at the top of flaring loops have strongly supported the scenario originally proposed by C-S-H-KP. Nonthermal energy input in hard X-rays and thermal energy estimated from soft X-rays are fundamentally consistent with the interpretation of thick-target and chromospheric-evaporation models (Neupert effect). X-ray jets, another discovery of Yohkoh, were also associated with magnetic reconnection, as a result of the interaction of emerging fluxes with pre-existing coronal loops. Temperature structures of active regions, quiet sun, and coronal holes had very dynamic differential-emission-measure (DEM) distributions and high-temperature tails of DEM were considered to come from the contribution of flare-like activity.

• Animal Systematics, Evolution and Diversity
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• 제28권4호
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• pp.304-307
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• 2012

A three specimen of Icelus toyamensis, belonging to Cottidae, Scorpaeniformes, was firstly collected from the East Sea, Korea during 2007-2009. We herein described the species as the first record from Korea on the basis of these specimens. Icelus toyamensis is characterized by the following morphological combinations: spinous scales absent on the base of dorsal fin; small ctenoid scales scattered on body sides; gill rakers are short, tubular, and relatively broad; the uppermost preopercular spine is sharp and simple; dorsal fin rays VIII-IX, 20-21; anal fin soft rays 18-19; pectoral fin rays 18, and vertebrae 40-41. New Korean name of I. toyamensis is proposed as "Min-jul-ga-si-hoet-dae."

• 천문학회보
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• 제35권2호
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• pp.57.2-57.2
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• 2010

Cosmic rays with energy exceeding 10^18eV are referred to as Ultra high energy cosmic rays (UHECRs). UHECR experiments have utilized air shower simulations to estimate the properties of cosmic rays. Telescope array (TA) experiment has used COSMOS and CORSIKA mainly; the Monte Carlo codes of CORSIKA and COSMOS simulate the evolution of extensive air showers in the atmosphere initiated by photons, hadrons or nuclei UHECRs. We compare the simulations from CORSIKA and COSMOS. Comparison has shown noticeable differences at the ground distributions, longitudinal distributions, Calorimetric energy, and Xmax value. The implications of our results are discussed.

• 천문학회보
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• 제43권1호
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• pp.39.1-39.1
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• 2018

Although it is agreed that the gamma-ray bursts (GRBs) invoke highly relativistic jets with bulk Lorentz factors of a few hundreds, the exact physical mechanism producing such powerful gamma-rays still remains debated. Three outstanding and important questions in the field concern (1) the composition of GRB jets (i.e., matter-dominated vs Poynting-flux-dominated), (2) the involved radiative process responsible for the observed gamma-rays (i.e., synchrotron mechanism vs photospheric radiation), and (3) the distance of the emitting region from the central engine where the prompt gamma-rays are released (i.e., ~10^12 cm vs 10^14 cm vs 10^16 cm). I will present recent important breakthroughs that we have made, which answer these three questions.