Smoking, drinking, and physical activity among Korean adults before and during the COVID-19 pandemic: a special report of the 2020 Korea National Health and Nutrition Examination Survey

Choi Sunhye,Bahk Jinwook,Park Suyeon,Oh Kyungwon,Jung-Choi Kyunghee 한국역학회 2022 Epidemiology and Health Vol.44 No.-

OBJECTIVES: This study aimed to describe trends in health behaviours between 2011 and 2020 and compare the changes in these behaviours between the 2020 COVID-19 pandemic and previous periods according to socio-demographic variables.METHODS: This study used data from the 2011 to 2020 Korea National Health and Nutrition Examination Survey. Current cigarette smoking, high-risk drinking, and inadequate physical activity levels were used as health behaviour indicators. The age-standardized prevalence, differences in prevalence between the periods, and the annual percentage change (APC) were calculated.RESULTS: Current cigarette smoking showed a decreasing trend (APC, -2.6), high-risk drinking remained unchanged, and inadequate physical activity levels increased (APC, 3.5) during 2011-2020. There were significant differences in high-risk drinking (3.1%p; 95% confidence interval [CI], 0.3 to 5.9) and inadequate physical activity levels (4.3%p; 95% CI, 0.4 to 8.1) between 2019 and 2020 in men. Among men, increased high-risk drinking was found in those aged 40-49 years, non-single households, urban residents, and the middle and highest income groups between 2019 and 2020. The low educational group and manual workers among men aged 30-59 years also showed an increased proportion of high-risk drinking. Inadequate physical activity levels also increased among men between 2019 and 2020 in those aged 30-39 years, non-single households, urban residents, and the upper-middle-income group.CONCLUSIONS: In the first year of the COVID-19 pandemic, Korean men’s high-risk drinking and inadequate physical activity levels increased. In addition to social efforts to reduce the spread of infectious diseases, active measures to positively change health behaviour are needed.

Intentions and Prospects of North Korean Strategy : Driving a Wedge between South Korea and the U.S. after the Death of Kim Jong Il

Choi, Jinwook Ewha Institute of Unification Studies 2012 Journal of peace and unification Vol.2 No.1

Surface Engineering Technologies for Mitigation and Repair of Chloride- Induced Stress Corrosion Cracking in Stainless-Steel Canisters for Spent

Jinwook Choi,Hwasung Yeom 한국방사성폐기물학회 2023 한국방사성폐기물학회 학술논문요약집 Vol.21 No.2

Safe management of spent nuclear fuel (SNF) is a key issue to determine sustainability of current light water reactor (LWR) fleet. However, none of the countries are actually conducting permanent disposal of SNFs yet. Instead, most countries are pursuing interim storage of spent nuclear fuels in dry cask storage system (DCSS). These dry casks are usually made of stainlesssteels for resistibility against cracking and corrosion, which can be occurred over a long-term storage period. Nevertheless, some corrosion called Chloride-Induced Stress Corrosion Cracking (CISCC) can arise in certain conditions, exacerbating the lifetime of dry casks. CISCC can occur if the three conditions are satisfied simultaneously: (i) residual tensile stress, (ii) material sensitization, and (iii) chloride-rich environment. A residual tensile stress is developed by the two processes. One is the bending process of stainless-steel plates into a cylindrical shape, and the other is the welding process, which can incur solidification-induced stress. These stresses provide a driving force of pit-to-crack transition. Around the fusion weld areas, chromium is precipitated at the grain boundary as a carbide form while it depletes chromium around it, leading to material susceptible to pitting corrosion. It is called sensitization. Finally, coastal regions, where nuclear power plants usually operate, tend to have a higher relative humidity and more chloride concentration compared to inland areas. This high humidity and chloride ion concentration initiate pitting corrosion on the surface of stainless-steels. To prevent initiation of CISCC, at least one of the three conditions should be removed. For this, several surface engineering techniques are under investigation. One of the most promising approaches is surface peening method, which is the process that impacts the surface of materials with media (e.g., small pins, balls, laser pulse). By this impact, plastic deformation on the surface occurs with compressive stress that counteracts with pre-existing residual tensile stress, so this approach can prevent pit-to-crack transition of stainless-steels. Also, cold spray deposition can prevent CISCC. Cold spray deposition is a method of spraying fine metal powder to a substrate by accelerating them to supersonic velocity with propellant gas. As a result, a thin coating composed of the feedstock powders can protect the substrate from outer corrosive environments. In addition, the impact of the feedstock powder on the substrate during the process provides compressive stress, similar to the peening method.

Intentions and Prospects of North Korean Strategy: Driving a Wedge between South Korea and the U.S. after the Death of Kim Jong Il

( Jinwook Choi ) 이화여자대학교 통일학연구원 2012 Journal of peace and unification Vol.2 No.1

Sharpness Enhancement and Super-Resolution of Around-View Monitor Images

Choi, Dong-Yoon,Choi, Ji-Hoon,Choi, Jinwook,Song, Byung Cheol IEEE 2018 IEEE transactions on intelligent transportation sy Vol.19 No.8

<P>In the wide-angle (WA) images embedded in an around-view monitor system, the subject(s) in the peripheral region is normally small and has little information. Furthermore, since the outer region suffers from the non-uniform blur phenomenon and artifact caused by the inherent optical characteristic of WA lenses, its visual quality tends to deteriorate. According to our experiments, conventional image enhancement techniques rarely improve the degraded visual quality of the outer region of WA images. In order to solve the above-mentioned problem, this paper proposes a joint sharpness enhancement (SE) and super-resolution (SR) algorithm which can improve the sharpness and resolution of WA images together. The proposed SE algorithm improves the sharpness of the deteriorated WA images by exploiting self-similarity. Also, the proposed SR algorithm generates super-resolved images by using high-resolution information which is classified according to the extended local binary pattern-based classifier and learned on a pattern basis. Experimental results show that the proposed scheme effectively improves the sharpness and resolution of the input deteriorated WA images. Even in terms of quantitative metrics such as just noticeable blur, structural similarity, and peak signal-to-noise ratio. Finally, the proposed scheme guarantees real-time processing such that it achieves 720p video at 29 Hz on a low cost GPU platform.</P>

Deriving rules for identifying diabetic among individuals with metabolic syndrome

Jinwook Choi,Yongmoo Suh 한국디지털정책학회 2018 디지털융복합연구 Vol.16 No.11

Fracture Resistance of K3 Nickel-Titanium Files Made from Different Thermal Treatments

Choi, JinWook,Oh, Soram,Kim, Yu-Chan,Jee, Kwang-Koo,Kum, KeeYeon,Chang, SeokWoo Hindawi Publishing Corporation 2016 Bioinorganic chemistry and applications Vol.2016 No.-

<P>The purpose of this study was to compare fracture resistances of K3 nickel-titanium files made from different thermal treatments. K3 (SybronEndo, Orange, CA), K3XF (SybronEndo), and experimentally heat treated K3 (K3H) were used. For the cyclic fatigue test, the samples were rotated with up-and-down motion in the artificial canal with the curvature of 60 degrees until the fracture occurred. The number of cycles to fracture (NCF) was measured. For the torsional fracture test, the samples were tightly bound and rotated until the fracture occurred. Elastic modulus (EM), ultimate torsional strength (UTS), and angle of rotation to fracture (ARF) were measured. The results were statistically analyzed by one-way ANOVA. The NCF of K3H was higher than those of K3 and K3XF (<I>P</I> < 0.05). The EM of K3XF and K3H was lower than that of K3 (<I>P</I> < 0.05). There was no significant difference in UTS. The ARF of K3XF was higher than that of K3 (<I>P</I> < 0.05). K3XF and K3H showed more flexibility than K3. The maximum torsional angle of K3XF was higher than that of K3, but there was no significant difference on the UTS in all three groups.</P>

Reliability-Based Multiview Depth Enhancement Considering Interview Coherence

Jinwook Choi,Dongbo Min,Kwanghoon Sohn Institute of Electrical and Electronics Engineers 2014 IEEE Transactions on Circuits and Systems for Vide Vol. No.

<P>Color-plus-depth video format has been increasingly popular in 3-D video applications, such as auto-stereoscopic 3-D TV and freeview TV. The performance of these applications is heavily dependent on the quality of depth maps since intermediate views are synthesized using the corresponding depth maps. This paper presents a novel framework for obtaining high-quality multiview color-plus-depth video using a hybrid sensor, which consists of multiple color cameras and depth sensors. Given multiple high-resolution color images and low quality depth maps obtained from the color cameras and depth sensors, we improve the quality of the depth map corresponding to each color view by increasing its spatial resolution and enforcing interview coherence. Specifically, a new up-sampling method considering the interview coherence is proposed to enhance multiview depth maps. This approach can improve the performance of the existing up-sampling algorithms, such as joint bilateral up-sampling and weighted mode filtering, which have been developed to enhance a single-view depth map only. In addition, an adaptive approach of fusing multiple input low-resolution depth maps is proposed based on the reliability that considers camera geometry and depth validity. The proposed framework can be extended into the temporal domain for temporally consistent depth maps. Experimental results demonstrate that the proposed method provides better multiview depth quality than the conventional single-view-based methods. We also show that it provides comparable results, yet much more efficiently, to other fusion approaches that employ both depth sensors and stereo matching algorithm together. Moreover, it is shown that the proposed method significantly reduces bit rates required to compress the multiview color-plus-depth video.</P>

The Current Implementation and Future Strategies of the Trust-Building Process

( Jinwook Choi ) 이화여자대학교 통일학연구원 2013 Journal of peace and unification Vol.3 No.2

In spite of the strained inter-Korean relations, the North Korea policy of the Park Geun-hye Administration enjoys considerable support at home and abroad, including the U.S. and China, more than any former government in South Korea. A survey indicates the decrease in the social conflict around the North Korea policy. The key to an efficient North Korea policy is to make an international consensus through policy alignment with the United States and China. It is also desirable to be flexible in policy measures to solve problems in a gradual trust-building process rather than clinging to a certain policy or area. Lastly, South Korea should push forward unification-oriented policies toward North Korea that goes beyond the dichotomy between maintenance of the status quo and preparation for unification.

Purifying Behavior of Photocalytic TiO₂ Anodized in Nitrate Ion Containing Solutions

Jinwook Choi,Seongeun Lee,Byunggwan Lee,Yongsoo Jeong,Han-Jun Oh,Choong-Soo Chi 한국표면공학회 2008 한국표면공학회 학술발표회 초록집 Vol.2008 No.-