• Korean Journal of Materials Research
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• v.30 no.5
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• pp.217-222
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• 2020

The design and fabrication of catalysts with low-cost and high electrocatalytic activity for the oxygen evolution reaction (OER) have remained challenging because of the sluggish kinetics of this reaction. The key to the pursuit of efficient electrocatalysts is to design them with high surface area and more active sites. In this work, we have successfully synthesized a highly stable and active NiCo₂S₄ nanowire array on a Ni-foam substrate (NiCo₂S₄ NW/NF) via a two-step hydrothermal synthesis approach. This NiCo₂S₄ NW/NF exhibits overpotential as low as 275 mV, delivering a current density of 20 mA cm^-2 (versus reversible hydrogen electrode) with a low Tafel slope of 89 mV dec^-1 and superior long-term stability for 20 h in 1 M KOH electrolyte. The outstanding performance is ascribed to the inherent activity of the binder-free deposited, vertically aligned nanowire structure, which provides a large number of electrochemically active surface sites, accelerating electron transfer, and simultaneously enhancing the diffusion of electrolyte.

• Journal of Korea Multimedia Society
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• v.19 no.9
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• pp.1647-1658
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• 2016

RGB+D database has been widely used in object recognition, object tracking, robot control, to name a few. While rapid advance of active depth sensing technologies allows for the widespread of indoor RGB+D databases, there are only few outdoor RGB+D databases largely due to an inherent limitation of active depth cameras. In this paper, we propose a novel method used to build outdoor RGB+D databases. Instead of using active depth cameras such as Kinect or LIDAR, we acquire a pair of stereo image using high-resolution stereo camera and then obtain a depth map by applying stereo matching algorithm. To deal with estimation errors that inevitably exist in the depth map obtained from stereo matching methods, we develop an approach that estimates confidence of depth maps based on unsupervised learning. Unlike existing confidence estimation approaches, we explicitly consider a spatial correlation that may exist in the confidence map. Specifically, we focus on refining confidence feature with the assumption that the confidence feature and resultant confidence map are smoothly-varying in spatial domain and are highly correlated to each other. Experimental result shows that the proposed method outperforms existing confidence measure based approaches in various benchmark dataset.

• Korean Journal of Human Ecology
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• v.12 no.3
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• pp.337-349
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• 2003

This study was dealt with consumers' attitudes and requests for refunds on the basis of data gathered in 1997 and 2000 and examined factors shaping the differences of the consumers' requesting for refunds and investigated variables influencing the presence or absence of requests for refunds. Research outcomes could be summarized as follows. First there were no differences in consumers' searches for information of refunds, degrees of satisfactions for practices of refunds, knowledges for refunds, consumers' expectation for the permission of refunds between two periods Consumers generally showed more active behaviors for the request for refunds in 2000 than in 1997. In cases of defects, the chance of getting refunds was higher while consumers feel greater needs for refund. Second, consumers perception for the necessity of refund and their expectations for successful outcomes were higher in cases of defects than in the opposite case; consumers were also more active to request for refunds and get more positive responses in the former case. Third, in cases of defects in 1997, as consumers faced the unsatisfactory response for their previous requests for refunds, they did not actively request for refunds. In 2000, requesting for refunds were more active as they were more knowledgeable, actively search for information of refunds before their purchases, and expect more positive outcomes for their requests for refund. On the other hand, in cases of no defects in 1997, consumers showed more active behaviors requesting for refunds as their own professional jobs, owned greater consumer expectation for positive outcomes and showed greater satisfactions for the previous requests of refunds. In the survey of 2000, consumers showed active behaviors requesting for refunds as they were highly educated, gather much information for refund, and showed positive expectations for the possibility of refund.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.8
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• pp.11-19
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• 2014

In recent SONAR (sound navigation and ranging) systems, wideband active SONAR systems has received more attention than narrowband SONAR systems due to the remarkable detection performance in terms of range resolution. However, the wideband SONAR systems usually requires a huge amount of computational burden in order to achieve their own superiority. To cope with this drawback of the wideband SONAR systems, this paper proposes a fast target detection and velocity estimation method using an extended replica in wideband hyperbolic frequency modulation active SONAR system. Computer simulation shows that the proposed method can be implemented by a highly reduced computational complexity with a little performance degradation in target detection and velocity estimation compared to the conventional filter bank method.

• Journal of Power Electronics
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• v.16 no.3
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• pp.1226-1235
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• 2016

For wearable health monitoring systems, a fundamental problem is the limited space for storing energy, which can be translated into a short operational life. In this paper, a highly efficient active voltage doubling rectifier with a wide input range for micro-piezoelectric energy harvesting systems is proposed. To obtain a higher output voltage, the Dickson charge pump topology is chosen in this design. By replacing the passive diodes with unbalanced-biased comparator-controlled active counterparts, the proposed rectifier minimizes the voltage losses along the conduction path and solves the reverse leakage problem caused by conventional comparator-controlled active diodes. To improve the rectifier input voltage sensitivity and decrease the minimum operational input voltage, two low power common-gate comparators are introduced in the proposed design. To keep the comparator from oscillating, a positive feedback loop formed by the capacitor C is added to it. Based on the SMIC 0.18-μm standard CMOS process, the proposed rectifier is simulated and implemented. The area of the whole chip is 0.91×0.97 mm², while the rectifier core occupies only 13% of this area. The measured results show that the proposed rectifier can operate properly with input amplitudes ranging from 0.2 to 1.0V and with frequencies ranging from 20 to 3000 Hz. The proposed rectifier can achieve a 92.5% power conversion efficiency (PCE) with input amplitudes equal to 0.6 V at 200 Hz. The voltage conversion efficiency (VCE) is around 93% for input amplitudes greater than 0.3 V and load resistances larger than 20kΩ.

• Food Engineering Progress
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• v.13 no.1
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• pp.50-55
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• 2009

The effect of active gluten supplementation on the quality properties of rice bagel was investigated. Water hydration capacity of rice flour increased as the amount of gluten increased, whereas alkaline water retention capacity decreased. Pelshenke value and sedimentation value were incerased as the amount of gluten increased, but these values are lower than those of strong wheat flour. Peak viscosity, setback, peak height, and peak width decreased as the amount of gluten increased. When the active gluten of 23% was added to the rice flour, the specific loaf volume of bagel increased more that two times compared with the active gluten of 11%. Hardness, gumminess, and chewiness were decreased as the amount of gluten increased. Specific loaf volume of bagel showed highly positive correlation in water hydration capacity, Pelshenke value, and sedimentation value of which values were r=0.962, r =0.964, and r =0.966, respectively.

• Korean Journal of Social Welfare
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• v.37
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• pp.217-239
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• 1999

The main premise of this study is that a successful treatment and rehabilitation of the mentally ill depends on an active. coping of their family members, who are the primary care-takers of the patients, even if families are confronting many difficulties because of caring their patients. Accordingly, this study aims to find out which factors are related to families active coping with the mentally ill. This study is conducted the survey with 191 family members of the mentally ills in order to discover: 1) what kinds of relations do exist between sociodemographic factors of the respondents, care-burden toward the mentally ill, and social supports, and the active coping, and 2) in what extent do these related factors affect on the active coping. The major findings of the study are: 1) gender and educational background of the respondents are positively related to the active coping; 2) regarding care-burden felt by the respondents, there is statistically significant positive relationship between - the respondents' burden due to a lack of social and institutional support and their active coping; 3) considering the relationship with social support, there is highly positive relationship between decision. emotional. material supports and the active coping; 4) using a multiple regression, respondents' sociodemographic background, care-burden, social support affect significantly on the active coping by 26.2% of explanatory power; and 5) using a step-wise multiple regression, the most powerful influenced factors on active coping are emotional support, burden due to a lack of social and institutional support, and educational background of the respondents. In conclusion, this study recommends clinicians to use an educational and support model for the families. All these efforts will contribute to enhance active coping of the families with the mentally ill.

• Bulletin of the Korean Chemical Society
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• v.24 no.4
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• pp.426-430
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• 2003

A range of methine dyes has been synthesized by condensation of highly electronegative active methylene compound dicyanomethylenecyclopentane derived from cyclopentanone with the formyl group of substituted benzaldehydes. The electronic absorption spectroscopic properties of the dyes were investigated. In general, substituents on the aromatic aldehyde moiety have a significant effect on the visible absorption maxima of the dyes; increasing the solvent polarity also showed a pronounced effect on the absorption maxima.

• RED RIBBON
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• s.58
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• pp.16-19
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• 2004

에이즈는 HIV$^{human immunodeficiency virus}$라는 바이러스에 의해 유발되므로 에이즈를 치료하기 위해서는 HIV를 우리 몸속에서 박멸하여야 한다. 1987년 AZT가 최초로 FDA의 공인을 받은 이래로 현재까지 여러 가지 약제들이 에이즈 치료에 사용되고 있다. 아직까지 HIV를 박멸하여 에이즈를 완치할 수 있는 치료제는 개발되지 않고 있으나 에이즈 치료제를 3가지 이상 복용하는 강력한 항레트로바이러스 요법highly active antiretroviral therapy, HAART을 시행함으로써 손상된 면역 기능을 회복시키고 기회감염을 줄여 좋은 효과를 보인다. 에이즈 치료제는 크게 세가지로 나눌 수 있다. 첫째는 뉴클레오사이드 역전사효소 억제제이고 둘째는 비뉴클레오사이드 역전사효소 억제제, 셋째는 단백분해효소 억제제이다. 현재 우리나라에서 사용되는 에이즈 치료제에 대해 알아보도록 하자.

• The Journal of the Korean life insurance medical association
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• v.29 no.1
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• pp.4-6
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• 2010

The life expectancy of HIV-infected subjects has improved dramatically since the introduction of highly-active antiretroviral therapy (HAART). Considering that patients with HIV infection are living longer, treatment plans should include those for the accompanying co-morbidities such as cardiovascular diseases, metabolic syndrome, malignancy, etc. This review discusses the impact of HAART on the epidemiology of survival and co-morbidities (malignancy and cardiovascular diseases) among HIV-infected subjects.