• The Journal of Engineering Research
• /
• v.4 no.1
• /
• pp.35-45
• /
• 2002

This paper deals with the scheduling problems which are the most important subtask in High-Level Synthesis. Especially, we have concentrated our attentions on the data-path scheduling which can get the structural informations from the behavioral algorithm as a first step in synthesis procedure. Suggest Forward scheduling methode is executed the ASAP and ALAP scheduling to use the fifth – order elliptic wave filter of a standard benchmark model, and then it is drawing up T.N matrix table by the number of resource and control-step, using the table extract of the simple than down-limit value of the control-step for the number of given resource to use this table. All of existing list scheduling techniques determine the priority functions first, and then do the operation scheduling, But, the suggested forward scheduling technique does the schedule first, and determines the priority functions if needed in scheduling process.

• Restorative Dentistry and Endodontics
• /
• v.28 no.5
• /
• pp.378-384
• /
• 2003

This study evaluated the influence of a desensitizer(MS coat) on microtensile bond strength of different adhesives:a three-step adhesive(All-Bond 2), a two-step adhesive(Single Bond), a one-step adhesive(One-up Bond F). Non-caries extracted human molars were used. Dentin surface was obtained by horizontal section on mid-portion of crown using a water-cooled low speed diamond saw. Teeth were randomly divided into 6 group. AMO(MS coat + All Bond), SMO(MS coat + Single Bond)- and OMO(MS coat + One-up Bond F)-dentin surface were treated with 17% EDTA before bonded adhesive. AMX-, SMX- and OMX-dentin surface were bonded with All-Bond 2, Single Bond and One-up Bond F, respectively. with no previous treatment with MS coat and 17% EDTA. About 1cm high resin composite($Z-250^{TM}$) were incrementally build-up on the treated surface. The specimens for the microtensile test were serially sectioned perpendicular to the adhesive layer to obtain $0.7{\times}0.7mm$ sticks. 30 sticks were prepared from each group. After that. tensile bond strength for each stick was measured with Microtensile Tester at a 1mm/min crosshead speed. Fractured dentin surfaces were observed under the SEM. The results were statistically analysed by using a One-way ANOVA and Tukey's test(p<0.05). Value in MPa were: $AMO-44.35{\pm}13.21;{\;}SMO-39.35{\pm}13.32;{\;}OMO-31.07{\pm}10.25;{\;}AMX-49.22{\pm}16.38;{\;}SMX-56.02{\pm}13.35;{\;}OMX-72.93{\pm}16.19$. Application of MS coat reduced microtensile bond strengths of both Single Bond and One-up Bond F, whereas microtensile bond strengths of All-Bond 2 were not affected significantly.

• The Transactions of the Korean Institute of Power Electronics
• /
• v.11 no.2
• /
• pp.142-148
• /
• 2006

In this paper, authors propose a novel step-up AC-DC converter operated with power factor correction (PFC) and with high efficiency. The proposed converter behaves with discontinuous current control (DCC) of input current. The input current waveform in the proposed converter is got to be a discontinuous sinusoid form in proportion to magnitude of at input voltage under the constant duty cycle switching. Therefore, the input power factor is nearly unity and the control method is simple. In the general DCC converters, the switching devices are turned-on with the zero current switching (ZCS). But turn-off of the switching devices is done at the maximum current. To achieve a soft switching at turn-off, the proposed converter uses a new partial resonant circuit, which results in the very low switching loss and the high efficiency of converter.

• Archives of Plastic Surgery
• /
• v.49 no.3
• /
• pp.296-303
• /
• 2022

Background In recent years thread lift has become widespread; however, existing methods need to improve their long-term outcome, which requires considering topographic anatomy of face and neck, especially the ligamentous apparatus. This study aims to assess the effectiveness and safety of an innovative method of one-time three-step thread facelift, which provides an additional support to the ligamentous structures of the upper, middle, and lower thirds of the face and neck. Methods The study included 357 patients aged 32 to 67 years with various morphotypes of aging. The original method of thread lift was applied, and its effectiveness was followed up for to 2 years. The Wrinkle Severity Rating Score (WSRS) and Global Aesthetic Improvement Scale (GAIS) scores were used for assessment by investigators, independent observers, and patients. Statistical significance was determined using paired t-test and chi-square test. Results The mean WSRS score was 3.88 ± 0.88 before the thread lift, 1.93 ± 0.81 one month after the procedure, and 2.36 ± 0.85 after 2 years of follow-up. The mean GAIS was 4.80 ± 0.04 one month after thread lift, and 4.01 ± 0.04 after 2 years, while in the patients' assessment Global Satisfaction Scale was 4.86 ± 0.02 and 4.10 ± 0.02, respectively. There were no clinically significant complications throughout the observation period. Conclusion The new method of one-time three-step thread fixation of the soft tissues of the face and neck demonstrated a high degree of satisfaction by both experts and patients after 2 years of follow-up. It showed high efficacy and safety, including in the group of patients with pronounced age-related changes of the skin of face and neck.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.23 no.9A
• /
• pp.2355-2364
• /
• 1998

In conventional fractal decoding procedure, the reconstructed image is obtained by a rpredefined number of iterations starting with an arbitrary initial image. Its convergence speed depends on the selection of the initial image. It should be solved to get high speed convergence. In this paper, we theoretically reveal that conventional method is approximately decomposed into the decoding of the DC and AC components. Based on this fact, we proposed a novel fast fractal decoding algorithm made up of two steps. The averaged-image considered as an optimal initial image is estimated in the first step. In the second step, the reconstructe dimag eis genrated from the output image obtained in the first step. From the simulations, it is shown that the output image of the first step approximately converges to the averaged-image with only 15% calculations for one iteration of conventional method. And the proposed method is faster than various decoding mehtods and evenly equal to conventioanl decoding with the averaged-image. In addition, the proposed method can be applied to the compressed data resulted from the various encoding methods because it does not impose any constraints in the encoding procedure to get high decoding speed.

• Journal of Electrical Engineering and Technology
• /
• v.1 no.3
• /
• pp.343-350
• /
• 2006

This paper introduces a new high efficient bi-directional, non-isolated DC/DC converter. Through variations of the topology of the conventional Cuk converter, an optimum bi-directional DC/DC converter is proposed. Voltage and current in the proposed DC/DC converter are continuous. Furthermore, the efficiency in both step-up and step-down mode is improved over that of the conventional bi-directional converter. To prove the validation for the proposed converter, simulations and experiments are executed with a 300W bi-directional converter.

• Journal of the Korean Society for Precision Engineering
• /
• v.17 no.2
• /
• pp.220-226
• /
• 2000

High precision step motor using Terfenol-D linear actuators is proposed and its performance is tested. Four Terfenol-D linear actuators are set up perpendicular to the rotor and saw-tooth current signals are applied on the actuators. It was found that the rotation angle is increased as the excitation current, the inertia of the rotor, and the contact force between the rotor and the push device are increased. The rotation angle per step of $0.001^{\circ}$ and blocking torque of 0.2Nm are achieved. The effect of the time delay between the excitation signals is also investigated.

• Journal of Electrical Engineering and Technology
• /
• v.11 no.4
• /
• pp.860-868
• /
• 2016

A bidirectional DC-DC converter (BDC) is an indispensable electrical unit for the electric vehicles (EVs). High efficiency, high power density, isolation, light weight and reliability are all essential requirements for BDC. In this paper, a 3 kW BDC for the battery charger of EVs is proposed. The proposed converter consists of a half-bridge structure on the primary side and an isolation transformer and a synchronous rectifier structure on the secondary side. With this topology, minimum number of switching devices are required for bidirectional power flow between the two dc buses of EVs. The easy implementation of the synchronous rectification gives advantages in terms of efficiency, cost and flexibility. The proposed BDC achieves high efficiency when operating in both modes (step-up and step-down). A 3 kW prototype is implemented to verify theoretical analysis and the performance of the proposed converter.

• Journal of Advanced Marine Engineering and Technology
• /
• v.29 no.7
• /
• pp.744-749
• /
• 2005

This paper describes the performance improvement of power control system of magnetron (MGT) for microwave oven. The MGT is used extensively in household microwave oven and industrial microwave heating devices, and is operated by 3.0[kV] $\∼$5.0[kV] dc high voltage. The proposed power supply is consisted of a bridge rectifier, step-up converter(SUC) and its controller, half bridge inverter(HBI) and its controller, and full wave double voltage rectifier(DVR). In the proposed system, a good power factor can be obtained by the SUC' switching method that the inductor current waveforms follows that of the rectified voltage, and a line input power can be controlled to a range of 17.5[$\%$] by duty ratio (DR) adjustment of the HBI.

• Proceedings of the KIPE Conference
• /
• 2009.11a
• /
• pp.84-86
• /
• 2009

Isolated boost converter is desirable in the dc/dc converter applications where isolation is required and a large step up is needed. In this paper, it is proposed and analyzed the isolated boost converter which can step up low input voltage to high output voltage using transformer. Instead of using a conventional scheme, the proposed converter has the reset winding for volt-sec balance of transformer. Finally, the validity of the proposed isolated boost converter is verified by simulation.