• Journal of Microbiology and Biotechnology
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• v.13 no.4
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• pp.495-500
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• 2003

Tight junctions (TJ) between adjacent Sertoli cells in testis are important for the formation of the blood testis barrier (BTB). In an effort to verify the reproductive health risk of endocrine-active chemicals (EACs), changes in the transepithelial electrical resistance (TER) and the expression of TJ genes were examined by co-planar polychlorinated biphenyl (PCB) treatment in cultured mouse Sertoli cells. Although the increase in TER of Sertoli cells was accelerated by 10 nM co-planar PCB, it was downregulated by 100 nM co-planar PCB. The expression of claudin-1 was downregulated by co-planar PCB in a concentration-dependent manner. On the contrary, the expression of claudin-1 was increased in the Sertoli cells by 10 nM co-planar PCB treatment. These results suggest that the structure and function of TJ may be targeted by co-planar PCB in Sertoli cells. Assessment of the structure and function of TJ in Sertoli cells might be useful for screening the reproductive health risk of EACs.

• Journal of Environmental Science International
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• v.20 no.8
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• pp.987-995
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• 2011

Co-planar PCBs(polychlorinated biphenyls) of non-ortho are investigated in soil and ginseng on the North Gyeongbuk with HRGC/HRMS. PCB77 in soil on Yeongju and Sangju are detected 0.0007 pgTEQ/g and 0.0009 pgTEQ/g, respectively. PCB81 in soil on Yeongju and Sangju are detected 0.0113 pgTEQ/g and 0.0108 pgTEQ/g, respectively. Also PCB126 in soil on Yeongju and Sangju are detected 0.0907 pgTEQ/g and 0.0944 pgTEQ/g, respectively. But PCB169 in soil on Yeongju and Sangju is not detected. Total Co-planar PCBs of non-ortho in soil on Yeongju and Sangju are 0.1027 pgTEQ/g and 0.1061 pgTEQ/g, respectively. PCB77 in ginseng on Yeongju and Sangju are detected 0.0008 pgTEQ/g. Then PCB81 in ginseng on Yeongju and Sangju are detected 0.0104 pgTEQ/g and 0.0112 pgTEQ/g, respectively. But PCB126 in ginseng on Yeongju and Sangju are detected 0.0585 pgTEQ/g and 0.0579 pgTEQ/g, respectively. PCB169 in ginseng on Yeongju and Sangju is not detected. Total Co-planar PCBs of non-ortho in ginseng on Yeongju and Sangju are 0.0697 pgTEQ/g and 0.0700 pgTEQ/g, respectively. Relationship of PCBs in between soil and ginseng shown significance($R^2$ : 0.99).

• Bulletin of the Korean Chemical Society
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• v.26 no.1
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• pp.63-71
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• 2005

Equilibrium geometries, electronic structures, and energies of borocarbon clusters (binary compounds of carbon and boron), an unexplored class of molecules with highly unusual characteristics and potential for further development, have been investigated by means of B3LYP/6-311+G$^*$ density functional theory computations. A large number of B$_7$C${_1}^{1-}$, B$_6C_2$, and B$_5C_{3}\,^{1+}$ clusters with planar and non-planar monocyclic and polycyclic rings, as well as cage structures, have been systematically studied. Unexpectedly, planar forms are predicted not only to be the most stable structures, but also, in many cases, to have unprecedented planar heptacoordinate boron (p-heptaB) and planar heptacoordinate carbon (p-heptaC) arrangements. All these pheptaB and p-heptaC have 6π electrons and are aromatic according to the nucleus independent chemical shift (NICS). This novel bonding pattern is analyzed in terms of natural bond orbital (NBO) analysis. For virtually all possible B$_7$C${_1}^{1-}$, B$_6C_2$, and B$_5C_{3}\,^{1+}$ combinations, the p-heptaB arrangements are the more stable than other type structures.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2003.05a
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• pp.19-22
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• 2003

The purpose of this study is to analyze the curing effect of planar surface heater for concreting in cold weather. Some experiments were conducted to evaluate the temperature history of concrete structures cured with heating sheets. Results are as follows ; (1) The temperature of concrete showed continuously rising trend with the heating by planar surface heater under the cold environmental condition of 3~-12$^{\circ}C$. And after about 24 hours the maximum temperature of concrete was reached at 25~3$0^{\circ}C$. (2) The temperature of slab concrete heated by planar surface heater of 130W/$m^2$ was at least $25^{\circ}C$ higher than that of an exterior air, and the curing performance was much more effective than heating by hot wind machine. (3) Through the curing by planar surface heater for 48 hours, the concrete maturity of about 1.5 times to heating by hot wind machine was acquired.

• Korean Journal of Materials Research
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• v.12 no.3
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• pp.195-199
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• 2002

Planar Hall effect of ferromagnetic GaMnAs thin films was investigated for the first time. The films were grown in an optimized growth condition via molecular beam epitaxy at low temperatures. For the optimization of the growth conditions, we used reflection high-energy electron diffraction, electrical conductivity, double crystal x-ray diffraction, and superconducting quantum interference device measurements techniques. We observed that the difference between the longitudinal resistance and the transverse resistance matches the planar Hall resistance. The ratio of the planar Hall resistance at saturation magnetic field to that at zero reached above 500%.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.19 no.4
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• pp.553-561
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• 2010

In flat panel display or semiconductor industries, they install the equipments with fine line width and high throughput for fabrication and inspection. The equipments are required to have the linear stage which can position the work-piece with high speed, fine resolution on wide range of motion. In this paper, a precision planar linear XY stage is proposed. The stage has a symmetric planar window configuration and is guided by air-bearings on granite plate. The symmetric planar window configuration makes the stage has robustness against dynamic and thermal disturbances. The air-bearings let the stage move smooth on straight guide bar and flat granite surface. The stage is actuated by linear motor with Halbach magnet array (HMA). HMA generates more confined magnetic flux than conventional array. The linear motors are optimized by using sequential quadratic programming (SQP) with the several constraints that are thermal dissipation, required power, force ripple and so on. The planar linear XY stage with the symmetric planar configuration and the linear motors is implemented and then the performance such as force ripple, resolution and stroke are evaluated.

• Journal of Institute of Control, Robotics and Systems
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• v.4 no.3
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• pp.360-371
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• 1998

In this paper, output precision characteristics of a planar 6 degree-of-freedom parallel mechanisms are investigated, where the 6 degree-of-freedom mechanism is formed by adding an additional link along with an actuated joint in each serial subchain of the planar 3 degree-of-freedom parallel mechanism. Kinematic analysis for the parallel mechanism is performed, and its first-order kinematic characteristics are examined via kinematic isotropic index, maximum and minimum input-output velocity transmission ratios of the mechanisms. Based on this analysis, two types of planar 6 degrees-of-freedom parallel manipulators are selected. Then, dynamic characteristics of the two selected planar 6 degree-of-freedom parallel mechanisms, via Frobenius norms of inertia matrix and power modeling array, are investigated to compare the magnitudes of required control efforts of both three large actuators and three small actuators when the link lengths of three additional links are changed. It can be concluded from the analysis results that each of these two planar 6 degrees-of-freedom parallel mechanisms has an excellent control-in-the-small characteristics and therefore, it can be very effectively employed as a high-precision macro-micro manipulator when both its link lengths and locations of small and large actuators are properly chosen.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.3C
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• pp.264-270
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• 2010

Non-planar screens such as cylinder and sphere shaped screens are widely used for high-resolution immersive visualization environments. An existing method employs quadric matrix that maps an image onto a curved screen. However if the shape of the screen changes or moves, the quadric matrix will not be valid. In this paper, we assume that the screen is a quadric shape and the screen movement or change are relatively small. Then we propose to use a piecewise planar approximations for the screen to compensate for the geometric distortion on a non-planar screen. We demonstrate the effectiveness and efficiency of the proposed method through experiments.

• Laser Solutions
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• v.18 no.1
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• pp.7-11
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• 2015

In this paper, micro trench structure is fabricated by femtosecond laser for inserting optical reflecting wavelength filter in planar waveguide. The width and depth of the trench is controlled by femtosecond laser machining condition. Also, large scale of single channel with 500um and 1000um on silica plate is fabricated by femtosecond laser, and roughness of the channel surface is polished by $CO_2$ laser for the insertion of the filter. Then, the characteristic of the planar waveguide inserted the filter is verified.

• Journal of Korea Multimedia Society
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• v.25 no.7
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• pp.912-921
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• 2022

Autonomous vehicles equipped with cameras, such as robots, fork lifts, or cars, can be found frequently in industry sites or usual life. Those cameras show planar motion because the vehicles usually move on a plane. Sometimes the cameras in fork lifts moves vertically. The cameras under planar and vertical motion provides useful properties for horizontal or vertical lines that can be found easily and frequently in our daily life. In this paper, some useful back-projection properties are suggested, which can be applied to horizontal or vertical line images captured by a camera under planar and vertical motion. The line images are back-projected onto a virtual plane that is parallel to the planar motion plane and has the same orientation at the camera coordinate system regardless of camera motion. The back-projected lines on the virtual plane provide useful information for the world lines corresponding to the back-projected lines, such as line direction, angle between two horizontal lines, length ratio of two horizontal lines, and vertical line direction. Through experiments with simple plane polygons, we found that the back-projection properties were useful for estimating correctly the direction and the angle for horizontal and vertical lines.