• Journal of Electrical Engineering and Technology
• /
• v.11 no.4
• /
• pp.943-950
• /
• 2016

In this paper, we propose to analyze the physical characteristics of a planar dual-composite right-left handed transmission line by a common application of Bond Graph approach and Scattering formalism (Methodology S.BG). The technique, we propose consists, on the one hand, of modeling of a dual composite right-left metamaterial transmission line (D-CRLH-TL) by Bond Graph approach, and, it consists of extracting the equivalent circuit of this studied structure. On the other hand, it consists to exploiting the scattering parameters (Scattering matrix) of the DCRLH-TL using the methodology which we previously developed since 2009. Finally, the validation of the proposed and used technique is carried out by comparisons between the simulations results with ADS and Maple (or MatLab).

• Journal of Korean Neurosurgical Society
• /
• v.61 no.5
• /
• pp.568-573
• /
• 2018

Objective : Thoracic pedicles have special and specific properties. In particular, upper thoracic pedicles are positioned in craniocaudal plane. Therefore, manipulation of thoracic pedicle screws on the left side is difficult for right-handed surgeons. We recommend a new position to insert thoracic pedicle screw that will be much comfortable for spine surgeons. Methods : We retrospectively reviewed 33 patients who underwent upper thoracic pedicle screw instrumentation. In 15 patients, a total of 110 thoracic pedicle screws were inserted to the upper thoracic spine (T1-6) with classical position (anesthesiologist and monitor were placed near to patient's head. Surgeons were standing classically near to patient's body while patients were lying in prone position). In 18 patients, a total of 88 thoracic pedicle screws were inserted to the upper thoracic spine with the new standing position-surgeons stand by the head of the patient and the anesthesia monitor laterally and under patient's belt level. All the operations performed by the same senior spine surgeons with the help of C-arm. Postoperative computed tomography scans were obtained to assess the screw placement. The screw malposition and pedicle wall violations were divided and evaluated separately. Cortical penetration were measured and graded at either : 1-2 mm penetration, 2-4 mm penetration and >4 mm penetration. Results : Total 198 screws were inserted with two different standing positions. Of 198 screws 110 were in the classical positioning group and 88 were in the new positioning group. Incorrect screw placement was found in 33 screws (16.6%). The difference between total screw malposition by both standing positions were found to be statistically significant (p=0.011). The difference between total pedicle wall violations by both standing positions were found to be statistically significant (p=0.003). Conclusion : Right-handedness is a problem during the upper thoracic pedicle screw placement on the left side. Changing the surgeon's position standing near to patient's head could provide a much comfortable position to orient the craniocaudal plane of the thoracic pedicles.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.23 no.1
• /
• pp.21-28
• /
• 2012

In this paper, we propose a flexible zeroth-order resonant(ZOR) antenna. Its zero phase constant ensures that the antenna performance is independent of substrate deformation. A composite right/left-handed transmission line is designed based on coplanar waveguide technology to realize the zeroth-order resonance phenomenon. The CRLH is an implementation of metamaterial(left handed material) which is composed of shunt inductance and series capacitance. In order to yield additional circuital parameter, chip inductor and gap capacitor is added, respectively. The proposed ZOR antenna provides good performances: reasonable bandwidth(6.5 %) and peak gain(0.69~1.39 dBi). Simulated and measured results show that the antenna's resonant frequencies and radiation patterns are almost unchanged at different curvature diameters of 30, 50, 70 mm, as well as for a flat surface.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.25 no.2
• /
• pp.156-163
• /
• 2014

In this paper, a compact circularly polarized metamaterial patch antenna using cross aperture-coupled feed is proposed. The CP antenna utilizes the -1 mode that is induced by the composit right-left handed(CRLH) transmission line. Since the -1 mode has the same properties with the $TM_{010}$ mode of the conventional patch antenna, the circular polarization(CP) can be realized. If two orthogonal modes are excited with $90^{\circ}$ phase difference, the CP property can be obtained. In order to obtain two orthogonal modes and $90^{\circ}$ phase difference, 4 mushroom structures having the shape of square are employed. The width and length of the cross aperture are optimized through the design algorithm. The fabricated antenna is based on RT/duroid5880 substrate and the total area of the 4 mushroom is $0.25{\lambda}_0{\times}0.25{\lambda}_0$. The center frequency of the LHCP(Left-Handed Circular Polarization) antenna is measured as 1.622 GHz and circular polarization bandwidth(3 dB) is measured as 3 MHz. The center frequency of the RHCP(Right-Handed Circular Polarization) antenna is measured as 1.609 GHz and circular polarization bandwidth (3 dB) is measured as 3 MHz, respectively. The measured radiation efficiency of LHCP antenna is 61.1 % and the measured radiation efficiency of RHCP antenna is 54.5 %.

• BMB Reports
• /
• v.29 no.1
• /
• pp.1-10
• /
• 1996

The binding interaction of ethidium to a series of synthetic deoxyoligonucleotides containing a B-Z junction between left-handed Z-DNA and right-handed B-DNA, was studied. The series of deoxyoligonucleotides was designed so as to vary a dinucleotide step immediately adjacent to a B-Z junction region. Ethidium binds to the right-handed DNA forms and hybrid B-Z forms which contain a B-Z junction, in a highly cooperative manner. In a series of deoxyoligonucleotides, the binding affinity of ethidium with DNA forms which were initially hybrid B-Z forms shows over an order of magnitude higher than that with any other DNA forms, which were entirely in B-form DNA The cooperativity of binding isotherms were described by an allosteric binding model and by a neighbor exclusion model. The binding data were statistically compared for two models. The conformation of allosterically converted DNA forms under binding with ethidium is found to be different from that of the initial B-form DNA as examined by CD spectra. The ratio of the binding constant was interestingly correlated to the free energy of base unstacking and the conformational conversion of the dinucleotide. The more the base stacking of the dinucleotide is unstable, or the harder the conversion of B to A conformation, the higher the ratio of the binding constant of ethidium with the allosterically converted DNA forms and with the initial B-Z hybrid forms. DNA sequence around a B-Z junction region affects the binding affinity of ethidium. The results in this study demonstrate that ethidium could preferentially interact with unusual DNA structures.

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.44 no.12
• /
• pp.1-7
• /
• 2007

This paper proposes the design method based on the composite right/left-handed (CRLH) structure to miniaturize and enhance the rejection performance in the stopband. For realization, we used the 0-th order resonance point of the unbalanced case of the CRLH and the simple theory of Inverter. The proposed technique is validated by the performance predictions and experiments, and it is found out that the suggested method enables the sire reduction of over 65 % from the conventional filters such as the parallel coupled type.

• Proceedings of the KIEE Conference
• /
• 2009.07a
• /
• pp.1507_1508
• /
• 2009

This study proposes a composite right/left-handed transmission line (CRLH-TL) that permits switching between the right-handed (RH) and left-handed (LH) modes using single crystalline silicon (SCS) RF MEMS switches. It is possible to change modes from the RH to LH mode, or vice versa, by controlling the admittance of capacitors and the impedance of inductors using switch operations. The proposed switchable CRLH-TL consists of SCS RF MEMS switches, metal-insulator-metal (MIM) capacitors and shunt inductors. At 8 GHz, the fabricated device shows a phase response of $87^{\circ}$ with an insertion loss of 2.7 dB in the LH mode, and a phase response of $-77^{\circ}$ with an insertion loss of 0.56 dB in the RH mode.

• Journal of the Ergonomics Society of Korea
• /
• v.30 no.5
• /
• pp.621-628
• /
• 2011

Objective: The aim of this study is to give interest about usability of cellular phone keypad for left-handed person. Background: Although there are being a lot of attempts to design suitable product on user's request in process that design cellular phone keypad, ergonomic access about left-handed person who compose decimal class is unprepared. Especially, in early user's occasion, left-handed persons need more efforts than right-handed person to master Hangul character input process skill level. But, since realization about this left-handed person's discomfort has not spread, the importance has not been well thought in the society. Method: (1) After extracting emblem to use in comparison in questionnaire, applied emblem uniformly to different 3 kind of cellular phone. (2) Measured Hangul input time and mistyping number by dominant hand's position and skill level to reagent. (3) Taking the result through ANOVA. Conclusion: In the result of the experiment about Hangul input time and mistyping number according to dominant hand's position and skill level, left-handed person's group on the low skill level has shown the dullest use capability among 4 experiment groups. Application: In the future, analysis result may be used to the data of realization conversion in process design of various products including cellular phone keypad to consider left-handed person.

• International Journal of Contents
• /
• v.11 no.3
• /
• pp.34-38
• /
• 2015

A band stop filter is proposed with cascading unit cells that are based on a dual composite right/left-handed (D-CRLH) conductorbacked coplanar waveguide. The parameters of the unit cell have been analyzed to confirm the behavior of each component for the equivalent circuit of the cell. We simulated the dispersion characteristics and energy distribution and have determined that the unit cell has a D-CRLH property. The band stop filter was implemented by symmetrically cascading two of the proposed unit cells. The experimental results for the band stop filter revealed a band rejection performance of 32 dB and a return loss of 0.35 dB in the stopband frequency range from 869MHz to 954MHz. Finally, we show that there is a good agreement in the experimental results and those obtained through the simulations.

• Journal of Biomedical Engineering Research
• /
• v.12 no.1
• /
• pp.23-28
• /
• 1991

In this study electrical impedance plethysmograph was developed and each ten digital blood flow was measured for eight nomal males and a patient tvith digital arterial reconstruction surgery. Blood flow of the digit with surgery was approximately fourty percent compared to that of the other normal digit. For the normal subjects, right - handed subjects generally have larger blood flow in right fingers than that in left fingers while it was reverse for the left - handed subjects. The relative average magnitude of the digltal blood flow Is the third, first, second, fourth, and fifth digit in descending order for the left and rich hand, respectively. Blood flow of the fifth digit for all subjec!s except one was the smallest among the five digits.