• Proceedings of the KIEE Conference
• /
• 1993.11a
• /
• pp.59-62
• /
• 1993

The evaluation of the temperature of the motor in operation is necessary for smaller and lighter design of motors and for the determination of insulation class. And the evaluation of the temperature in thermal transient state is necessary for the determination of the intermittent rating and the protection from the thermal overload. The temperature can be calculated exactly by considering the loss distribution, the thermal resistances and the thermal capacities dependent on temperature. Using the detailed thermal equivalent circuit, the temperature of any local part of the motor can be evaluated. The comparison between the calculated results and the experiments is performed to verify the validity of the analysis.

• Proceedings of the IEEK Conference
• /
• 2002.07b
• /
• pp.723-726
• /
• 2002

This paper describes the design, fabrication, and measurement of a sequential-rotation microstrip-array antenna for the Electronic Toll Collection System (ETCS). The ETCS is made possible by using roadside equipment with radiation pattern that can accurately pinpoint the designated communication area, without interference from other lanes. The sequential-rotation microstrip-array antenna was applied to the absorber to reduce the side lobe level (SLL). Results showed that the antenna yields a return loss at a center frequency of -20.675 dB, an axial ratio of 1.15 dB, and a gain of 20.26 dBi.

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.41 no.1
• /
• pp.69-72
• /
• 2004

A bandpass filter has been designed by employing the PBG structure and the aperture on the ground together in this paper. The harmonics of band pass filter have been suppressed by employing the PBG structure and the bandwidth of it has been broadened by using the aperture on the ground. The three kinds of PBG structures has been combined to suppress the harmonics of the filter The center frequency of filter is 2.2 GHz and the bandwidth has been increased from $40\%$ by the aperture and all harmonics were suppressed about 35dBc by the PBG. The insertion loss has been reduced 3.0dB to 2.6dB.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
• /
• 2002.11a
• /
• pp.241-245
• /
• 2002

Dual-band microstrip antenna is designed for industrial-scientific-medical(ISM) band of 2.4㎓ and 5.8㎓ using finite-difference time-domain method(FDTD). Cross Patch fed by aperture in the ground plane of microstrip line is proposed as radiation element of antenna, which is 2 rectangular Patch is overlapped. To design antenna, change of input impedance by aperture and stub length change is examined. And it is investigated that center frequency and -10 ㏈ bandwidth by Length of radiation element and width change. Experimental result about reflection Loss confirmed that agree well with analysis results of FDTD and IE3D, And -3 ㏈ beam width, front to back ratio and gain in frequency 2.43㎓ and 5.79㎓ is presented by measuring radiation Pattern of antenna.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.29 no.4 s.235
• /
• pp.606-613
• /
• 2005

Effects of circumferentially local wall thinning on the fracture behavior of pipes were investigated by monotonic four-point bending. Local wall thinning was machined on the pipes in order to simulate erosion/corrosion metal loss. The configurations of the eroded area included an eroded ratio of d/t= 0.2, 0.5, 0.6, and 0.8, and an eroded length of ${\ell}\;=10mm,$ 25mm, and 120mm. Fracture type could be classified into ovalization, local buckling, and crack initiation depending on the eroded length and eroded ratio. Three-dimensional elasto-plastic analyses were also carried out using the finite element method, which is able to accurately simulate fracture behaviors excepting failure due to cracking. It was possible to predict the crack initiation point by estimating true fracture ductility under multi-axial stress conditions at the center of the thinned area.

• Clinical and Experimental Pediatrics
• /
• v.52 no.1
• /
• pp.22-27
• /
• 2009

Retinopathy of prematurity (ROP) is a major cause of blindness that affects premature infants. With advances in neonatology, ROP is likely to emerge as the most serious problem of vision loss in children even in developed countries; such a situation could be called the third epidemic of ROP. However, controversy and uncertainty still surround favorable outcomes of ROP. For successfully controlling ROP, timely and accurate screening is crucial because early treatment leads to favorable outcomes. Standard guidelines, including ROP classification, have provided satisfactory instructions for the screening and treatment of ROP. To improve the structural and functional outcomes of ROP, optimizing the timing of surgical interventions including cryotherapy, laser-photocoagulation, encircling, and vitrectomy is essential; these interventions can prevent the sequelae of ROP. It is essential for the neonatologist and the ophthalmologist to cooperate extensively for the successful treatment of ROP.

• Clinical and Experimental Pediatrics
• /
• v.54 no.8
• /
• pp.317-321
• /
• 2011

Children who suffer from steroid-resistant nephrotic syndrome (SRNS) require aggressive treatment to achieve remission. When intravenous high-dose methylprednisolone fails, calcineurin inhibitors, such as cyclosporine and tacrolimus, are used as the first line of treatment. A significant number of patients with SRNS progress to end-stage renal disease if remission is not achieved. For these children, renal replacement therapy can also be problematic; peritoneal dialysis may be accompanied by significant protein loss through the peritoneal membrane, and kidney allograft transplantation may be complicated by recurrence of SRNS. Plasmapheresis and rituximab were initially used for treatment of recurrent SRNS after transplantation; these are now under consideration as rescue therapies for refractory SRNS. Although the prognosis of SRNS is complicated and unfavorable, intensive treatment in the early stages of the disease may achieve remission in more than half of the patients. Therefore, timely referral of pediatric SRNS patients to pediatric nephrology specialists for histological and genetic diagnosis and treatment is highly recommended.

• Fashion & Textile Research Journal
• /
• v.13 no.6
• /
• pp.959-965
• /
• 2011

The purpose of this study was to evaluate the effect of wearing induced micro current brassiere on the physiological responses of women. Four women participated to wear a different brassiere condition: with and without micro current chips. Subjects were carried out after wearing the induced micro current brassiere for 120minutes. Eardrum temperature, skin temperature, blood pressure, heart rate, thermal perception, humid perception, and comfort perception were obtained. The results were as follows. The brassiere with micro current chips showed better performance on weight loss than the brassiere without micro current chips. Participants in a higher level of BMI were more likely to lose greater weight. Mean skin temperatures decreased with micro current chips. Participants felt more comfortable for walking in micro current brassiere than in brassiere without micro current chips.

• Proceedings of the IEEK Conference
• /
• 2001.06b
• /
• pp.181-184
• /
• 2001

A coplanar waveguide(CPW) on a dielectric substrate consists of a center strip conductor with semi-infinite ground planes on either side. This type of waveguide offers several advantages over microstrip line. It facilitates easy shunt as well as series mounting of active and passive devices. It eliminates the need for wraparound and via holes, and it has a low radiation loss. These, as well as several other advantages, make CPW ideally suited for microwave integrated circuit applications. However, very little information is available in the literature on models for CPW discontinuities. This lack of sufficient discontinuity models for CPW has limited the application of CPW in microwave circuit design. We presented for the characteristics of coplanar waveguide open end capacitance and series gap capacitance. Measurements by utilizing the resonance method were made and the experimental data confirmed the validity of theories. The relationships between the CPW capacitances and the physical dimensions were studied.

• Journal of the Korean Institute of Telematics and Electronics A
• /
• v.32A no.9
• /
• pp.1229-1235
• /
• 1995

In this paper an elliptic response dual-mode 4-pole bandpass filter was designed, manu-factured, and tested. A dual-mode filter having two stages cascaded double-tuned cavities which are resonant in two independent orthogonal TE113 circular-cavity modes and provide a bandpass response. A 4-pole dual-mode elliptic function bandpass filter has a center frequency of 14.022 GHz with a bandwidth of 36 MHz which is the first channel of the KOREASAT up-link frequency. The measured experimental results of a dual-mode filter are 1 dB insertion loss in the passband and 20 dB out-of-rejection.