• Transactions on Electrical and Electronic Materials
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• v.4 no.5
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• pp.19-23
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• 2003

Time-resolved photoluminescence from InGaN/GaN multi-quantum well structures was investigated for two different shapes of square-and trapezoidal wells grown by metal-organic chemical vapor deposition. To compare to the conventional square well structure with a radiative recombination lifetime of 0.170 nsec, the large value of lifetime of 0.540 nsec from trapezoidal well were found at room temperature. This value is similar to the value for GaN host material indicating no confinement effect of quantum well. Furthermore, the high resolution transmission electron microscopy image provides the In clustering effect in the trapezoidal well structure.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.35D no.9
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• pp.54-61
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• 1998

A new Triple well structure is proposed for improved latch-up immunity at deep submicron CMOS device. Optimum latch-up immunity process condition is established and analyzed with varying ion implantation energy and amount of dose and also compared conventional twin well structure. Doping profile and structure are investigated using ATHENA which is process simulator, and then latch-up current is calculated using ATLAS which is device simulator. Two types of different process are affected by latch-up characteristics and shape of doping profiles. Finally, we obtained the best latch-up immunity with 2.5[mA/${\mu}{m}$] trigger current using 2.5 MeV implantation energy and 1$\times$10$^{14}$ [cm$^{-2}$ ] dose at p-well

• Bulletin of the Korean Chemical Society
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• v.35 no.3
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• pp.775-782
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• 2014

The importance of including spin-orbit interactions for the correct description of structures and vibrational frequencies of haloiodomethanes is demonstrated by density functional theory calculations with spin-orbit relativistic effective core potentials (SO-DFT). The vibrational frequencies and the molecular geometries obtained by SO-DFT calculations do not match with the experimental results as well as for other cations without significant relativistic effects. In this sense, the present data can be considered as a guideline in the development of the relativistic quantum chemical methods. The influence of spin-orbit effects on the bending frequency of the cation could well be recognized by comparing the experimental and calculated results for $CH_2BrI$ and $CH_2ClI$ cations. Spin-orbit effects on the geometries and vibrational frequencies of $CH_2XI$ (X=F, Cl, Br, and I) neutral are negligible except that C-I bond lengths of haloiodomethane neutral is slightly increased by the inclusion of spin-orbit effects. The $^2A^{\prime}$ and $^2A^{{\prime}{\prime}}$ states were found in the cations of haloiodomethanes and mix due to the spin-orbit interactions and generate two $^2E_{1/2}$ fine-structure states. The geometries of $CH_2XI^+$ (X=F and Cl) from SO-DFT calculations are roughly in the middle of two cation geometries from DFT calculations since two cation states of $CH_2XI$ (X=F and Cl) from DFT calculations are energetically close enough to mix two cation states. The geometries of $CH_2XI^+$ (X=Br and I) from SO-DFT calculations are close to that of the most stable cation from DFT calculations since two cation states of $CH_2XI$(X=Br and I) from DFT calculations are energetically well separated near the fine-structure state minimum.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.12
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• pp.4909-4913
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• 2015

Objective: To explore the preventive effect of aspirin on the cardiovascular complications in prostate cancer after endocrinotherapy. Materials and Methods: A total of 92 patients with prostate cancer were divided into observation group (n=44) and control group (n=48). The control group was treated with medical castration plus anti-androgenic drugs. Based on the above treatment, the observation group was added aspirin. The follow-up duration was 2 years. The changes of partial prothrombin time (PT), activated partial thromboplastin time (APTT), platelet aggregation rate (PAG), prostate-specific antigen (PSA) and serum testosterone (T) before and after treatment as well as incidence of cardiovascular disease were observed. Results: The 2-year survival rates of patients without cardiovascular disease in observation group and control group were 95.45% (42/44) and 72.92% (35/48), respectively, and significant difference was presented between two groups by comparison to the survival rates ($x^2=8.5453$, p=0.0035). There was no statistical significance between two groups as well as before and after treatment regarding PT (p>0.05). After treatment, APTT went down and PAG was gradually on the rise in control group, while PAG down and APTT on the rise increasingly in observation group. Significant differences were presented between two groups as well as before and after treatment (p<0.01). Both PSA and T levels were decreased significantly in two groups after treatment (p<0.01), but there was no statistical significant between two groups (p>0.05). Conclusions: Application of endocrinotherapy in prostate cancer can easily lead to occurrence of cardiovascular disease, but cardiovascular complications can be prevented by aspirin, without affecting the effect of endocrinotherapy.

• The Journal of the Acoustical Society of Korea
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• v.21 no.4E
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• pp.146-155
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• 2002

We present a new technique for achieving source separation when given only a single charmel recording. The main idea is based on exploiting the inherent time structure of sound sources by learning a priori sets of time-domain basis functions that encode the sources in a statistically efficient manner. We derive a learning algorithm using a maximum likelihood approach given the observed single charmel data and sets of basis functions. For each time point we infer the source parameters and their contribution factors. This inference is possible due to the prior knowledge of the basis functions and the associated coefficient densities. A flexible model for density estimation allows accurate modeling of the observation, and our experimental results exhibit a high level of separation performance for simulated mixtures as well as real environment recordings employing mixtures of two different sources. We show separation results of two music signals as well as the separation of two voice signals.

• Journal of the Korean Home Economics Association
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• v.33 no.5
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• pp.167-176
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• 1995

This study is to present various curtain design by simulating method of the 32 case's combination of the styles, the patterns, the colors of curtain design for 50 woman collage students by photo shop program. The major findings of this study can be summarized as follow : The evaluation factors of curtains design was classified into three groups ; emotionality, harmoniousness, stimulus. The best choice to emphasize the atmosphere for "emotionality" of the first factor is curtain with the valance of cloud style, mixed Diagram pattern and ivory color(NO.16). The best choice to emphasize the atmosphere for "harmoniousness" as well as "stimulus" is curtain with the valance of two pieces cloud style, flower pattern and pink color(NO.18). The best choice to emphasize the atmosphere for "emotionality" and "stimulus" as well as "emotionality" and "harmoniousness" is curtain with the valance of natural fold style, stripes pattern and pink color(NO.6). The best choice to emphasize the atmosphere for "harmoney" and "stimulus" is curtain with the valance of two pieces cloud style, flower pattern and pink color(NO.18). The best choice to emphasize the atmosphere for "emotionality", "harmoniousness" and "stimulus" is curtain with the valance of two pieces cloud style, flower pattern and pink color(NO.18).

• Journal of the Korean Society for Precision Engineering
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• v.25 no.10
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• pp.67-76
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• 2008

In this research, a simple technique for designing PID controller, which guarantees robust stability for two-mass systems with parameter uncertainties as well as rigid-body behavior and zero steady-state error,is described. As well, such a PID controller is designed to mate two important frequencies, at which the given system is excited, very close so that an appropriate reference profile generated by using command shaping techniques can cover those two frequencies. Root-locus analysis. which shows traces of closed-loop poles for the given system, is used to design this PID controller. Finally, feedforward controller is added to improve tracking performance of the closed-loop system. Simulation for a system with a flexible mode and parameter uncertainties is executed to prove the feasibility of this technique.

• Journal of Chest Surgery
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• v.28 no.3
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• pp.253-257
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• 1995

Forty-eight patients with significant left main coronary artery obstruction underwent coronary artery bypass graft between September,1989 and September,1993. They consisted of 29 males and 19 females with the mean age of 58 [range 33 - 78 . Seventeen patients[35% had stenosis in left main coronary artery only and twenty-nine[61% had associated lesions in other coronary artery systems as well.Two[4% had isolated left coronary ostial lesion. The operative mortality was 4.17% [2/48 which is comparable to the mortality of overall coronary artery bypass surgery cases during the same period[p >0.05 . Perioperative myocardial infarction was occurred in two patients[4.17% . And the infarction rates between the two groups also showed no difference[p >0.05 . The forty-six survivors showed significant improvement in exercise tolerance as well as symptomatology. We conclude that surgery for left main coronary artery disease can be done with no increased risk through careful anesthesia,surgery, and aggressive postoperative care in the critical period.

• KIEE International Transactions on Electrophysics and Applications
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• v.3C no.2
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• pp.43-47
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• 2003

Lead zirconate titanate (PZT) thin films were fabricated by the pulsed laser ablation deposition (PLAD) method onto Pt/Ti/SiO$_2$/Si substrates. Crystalline phases as well as preferred orientations in PZT films were investigated by X-ray diffraction analysis (XRD). The well-crystallized perovskite phase and the (101) preferred orientation were obtained by two-step annealing at the conditions of $650^{\circ}C$, 1 hour. It was found that the temperature for the pulsed laser ablated PZT films annealed via a two-step annealing process can be reduced 20$0^{\circ}C$ compared to that of the conventional three-step annealing temperature profile for enhancing the transformation of the perovskite phase. The remanent polarization and the coercive field of this film were about 20 $\mu$C/$\textrm{cm}^2$ and 46 kV/cm, while the dielectric constant and loss values measured at 1 KHz were approximately 860 and 0.04, respectively. The interesting phenomena of this film, such as vertical shift in hysteresis curve, are also discussed.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.18 no.11
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• pp.1767-1773
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• 1993

In this paper, the coupling characteristics as well as the self and the mutual Impedance of a two-element probe-fed stacked circular microstrip array antennas are presented. A full wave analysis for the structure is performed In the spectral domain using the vector Hankel transform(VHT). Also, we presented measured results for the impedance, the coupling characteristics of the antenna and the variation of the coupling with the distance between the two elements. Finally, the calculated and measured results are shown to agree well wlth each other through comparisons.