• The Korean Journal of Zoology
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• v.39 no.2
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• pp.198-206
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• 1996

Adhesive membranes in the oocvtes of four loach fishes of Korea were investigated by light and electron microscopes to clarify the structural characteristics among the species. In the vitellosenic stage the adhesive membranes of oocvtes could be classified into two forms as follows: 1) fence-shaped form of Nemacheilus yoni and 2) non-adhesive membranous form of Misgurnus anguillicoudotus, M. Mizolepis, and Lefuo costuto. The adhesive membranes of oocvtes in the loach fishes showed a species specificity with reference to their habitats and spawning properties.

• Applied Microscopy
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• v.49
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• pp.4.1-4.2
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• 2019

We applied the advanced bitmap-assisted patterning function of focused ion beam to fabricate microscale sculpture of the 'BangTanSoNyeonDan' known as BTS members, the world-wide famous K-pop boyband. With the help of an electron microscope, you can carve your idols on your accessories at micro scale. Fun applications of electron microscopes are not limited to science.

• International Journal of Precision Engineering and Manufacturing
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• v.9 no.2
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• pp.18-22
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• 2008

The pitch and orthogonality of two-dimensional (2-D) gratings were measured using a metrological atomic force microscope (MAFM), and the measurement uncertainty was analyzed. Gratings are typical standard devices for the calibration of precision microscopes, Since the magnification and orthogonality in two perpendicular axes of microscopes can be calibrated simultaneously using 2-D gratings, it is important to certify the pitch and orthogonality of such gratings accurately for nanometrology. In the measurement of 2-D gratings, the MAFM can be used effectively for its nanometric resolution and uncertainty, but a new measurement scheme is required to overcome limitations such as thermal drift and slow scan speed. Two types of 2-D gratings with nominal pitches of 300 and 1000 nm were measured using line scans to determine the pitch measurement in each direction. The expanded uncertainties (k = 2) of the measured pitch values were less than 0.2 and 0.4 nm for each specimen, and the measured orthogonality values were less than $0.09^{\circ}$ and $0.05^{\circ}$, respectively. The experimental results measured using the MAFM and optical diffractometer agreed closely within the expanded uncertainty of the MAFM. We also propose an additional scheme for measuring 2-D gratings to increase the accuracy of calculated peak positions, which will be the subject of future study.

• ALGAE
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• v.19 no.3
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• pp.201-205
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• 2004

An ectoparasitic din flagellate infesting plank tonic chaetognath, Sagitta crassa Tokioka was found, for the first time, from Korean coasts. In order to identify the species, we investigated detailed morphology of the din flagellate using Nomarski interference optics as well as epifluorescent microscopes. The parasitic din flagellate consists of an oval to rod-shaped cell with a peduncle, by which the organism attaches to the host. The cell is covered with polygonal thecal plates. The nucleus displays two different shapes according to cell cycle stages: in young trophont the nucleus is elongated and shows typical din flagellate nucleus (dinokaryon), while in matured trophont, the nucleus is dome-shaped and non-dinokaryotic. The peduncle is variable in length and is ornamented with the longitudinal striations. All these characteristics point to identity that the ectoparasitic din flagellate infecting Sagitta crassa in Korean coasts is Oodinium inlandicum Horiguchi et Ohtsuka, originally described from the Seto Inland Sea of Japan. Relationship between prevalence and host sizes differed from those in Japan.

• Journal of Industrial Technology
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• v.20 no.A
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• pp.279-283
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• 2000

Lime is one of the world's most useful chemicals and manufactured in various types of kilns, using various fuels. Quicklimes vary in reactivity with water due to variations in the time and temperature calcining process and type of kiln used. Careful attention and control of time and temperature in the calcining process is necessary to insure a highly reactive lime. Excess time and temperature will cause the lime to be over burned. The highest reactivity of quicklime is obtained by calcination of limestone in the particle size of 0.1cm~2cm, calcination temperature of $1000^{\circ}C$, calcination time 90min. It was found by the scanning electron microscopes that pores of quick lime is reducted if the soft burned quick lime is heated continually.

• Ceramist
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• v.10 no.3
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• pp.55-66
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• 2007

Infrared Scanning Near-field Optical Microscopy (IR-SNOM) is an extremely powerful analytical instrument since it combines IR spectroscopy's high chemical specificity with SNOM's high spatial resolution. In order to do this in the infrared, specialty chalcogenide glass fibers were fabricated and their ends tapered to generate SNOM probes. The fiber tips were installed in a modified near field microscope and both inorganic and biological samples illuminated with the tunable output from a free-electron laser located at Vanderbilt University. Both topographical and IR spectral images were simultaneously recorded with a resolution of ${\sim}50\;nm$ and ${\sim}100\;nm$, respectively. Unique spectroscopic features were identified in all samples, with spectral images exhibiting resolutions of up to ${\lambda}/60$, or at least 30 times better than the diffraction limited lens-based microscopes. We believe that IR-SNOM can provide a very powerful insight into some of the most important bio-medical research topics.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1998.06a
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• pp.284-287
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• 1998

It is important to develop a method of assembling a set of sub pictures automatically into a mosaic picture , because a view through fiberscopes or microscopes with higher magnifying power is much larger than the field of view taken by a camera. This paper presents a method of assembling sub pictures, where roughly estimated junctions called approximate junctions are employed for matching triangles formed by selected junctions in sub pictures. To over come the difficulties in processing speed and noise corruption, fuzzy rules is applied to get fuzzy values for existence of approximate junctions and fuzzy similarity for congruent triangle matching. Some demonstration, exemplified by assembling microscopic metal matrix photographs, are given to show feasibility of this method.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2004.04a
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• pp.466-471
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• 2004

In focused-ion-beam (FIB) application of micromachining and device transplantation, four kinds of FIB processes, namely FIB sputtering, FIB-induced etching, redeposition, and FIB-induced deposition, are well utilized. As with FIB systems, scanning electron microscopes(SEMs) were extensively used in the semiconductor industry. They are the tools of choice for defect review and providing the image resolution needed for process monitoring. The enhanced capabilities of a dual-column on one chamber system are quickly becoming realized by the nano industry for performing a wide range of application.

• Applied Microscopy
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• v.20 no.2
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• pp.46-56
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• 1990

Ultrastructure of the hemopoietic organ in the grasshopper, Euprepocnemis shirakii, was studied using light and electron microscopes. The hemopoietic organs located on the upper surface of the dorsal diaphragm between 1st and 8th segments were consisted of 3 kinds of cells; the reticular cells, stem cells and two types of granulocytes. The reticular cells had numerous cytoplasmic processes and forming a complex network. Characteristically, pinocytotic vesicles and rough endoplasmic reticulum were well developed in this cell. The stem cells give rise to differentiating hemocytes of the different cell lineages. Granulocytes within the hemopoietic organs were originated from the stern cells and differentiated into two types of hemocytes ; granulocyte( I ), granulocyte( II ).

• Applied Microscopy
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• v.17 no.2
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• pp.72-84
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• 1987

Histochemical and ultrastructural properties on the cutaneous mucous glands of the water toad, Bufo stejnegeri Schmidt, are studied with light and electron microscopes. Mucous glands of the water toad are simple alveolar glands which are composed of gland cavity in dermis and gland duct in epidermis. Each gland cavity of the mucous glands is consisted of outmost myoepithelial cells, glandular epithelial cells and inner cavity. Gland cavities of the mucous glands are composed of four kinds of glandular epithelial cells which are the dark cell, the light cell, the mucous containing cell and the small cell. Secretory materials which are certified as acid mucopolysaccharides by the histochemical reactions are synthesized through the Golgi complexes of the mucous containing cells.