안면 마스크 착용이 심폐체력에 미치는 영향

류종식 ( Ryu¸ Jongsik ),김종근 ( Kim¸ Jonggeun ) 한국체육학회 2021 한국체육학회지 Vol.60 No.2

본 연구는 코로나 19 팬데믹으로 인하여 마스크 착용이 일상화된 현 상황에 마스크 착용이 성인 남성의 심폐체력에 미치는 영향을 알아보기 위한 것이다. 이를 위해 남자대학생 11명을 대상자로 선정하여 마스크 미착용(NM), 비말차단마스크 착용(KF-AD), KF94 마스크 착용(KF94), 총 3회에 걸쳐 운동부하검사를 실시하였다. 본 연구의 결과는 다음과 같다. 첫째, 안정 시 마스크 착용 여부 및 마스크 종류는 심박수, 분당환기량, 호흡교환율, 1회 호흡량, 수축기와 이완기 혈압에 유의한 영향을 미치지 않았다. 둘째, 최대부하 운동 시 마스크 착용 여부는 분당 호흡수에는 유의한 영향이 나타나지 않았다. 반면, 심박수(p<.001, KF-AD, KF94 < NM), 분당환기량(p<.001, KF-AD, KF94 < NM), 1회 환기량(p<.001, KF-AD, KF94 < NM), 운동지속시간(p<.05, KF-AD, KF94 < NM), 최대산소섭취량(p<.001 KF-AD, KF94 < NM), 그리고 환기역치(p<.001, KF-AD, KF94 < NM)의 경우 최대부하 운동 시 마스크 착용이 심폐체력에 유의한 영향을 미쳤다. 하지만 마스크 종류에 따른 유의한 차이는 나타나지 않았다. 이상의 결과를 종합하면 마스크 착용은 최대부하 운동 시 환기능력에 영향을 미쳐 최대산소 섭취량과 환기역치 등의 유산소 퍼포먼스를 감소시켰다. 이러한 결과들은 마스크 착용 후 운동 시 운동강도 재설정 및 유산소 퍼포먼스 측정 시 마스크의 영향에 대한 재고가 필요하다는 것을 확인할 수 있었다. 후속 연구에서는 다양한 종류의 마스크 착용에 관한 연구와 실험대상의 범위와 규모의 확대를 통한 데이터 누적을 바탕으로 마스크 착용 시 유산소성 체력 기준 정립 및 운동강도 설정에 관한 연구를 제언한다. The purpose of this study was to investigate the effect of wearing facial masks due to COVID-19 pandemic on cardiopulmonary exercise performance in adult men. To achieve this purpose 11 male university students were participated, followed by three exercise load tests: non-mask (NM), KF-AD mask wear (KF-AD), KF94 mask wear (KF94). The results of this study was as follows. First, the mask did not significantly affect HR, VE, RR, TV, SBP and DBP. Second, wearing a mask during maximum load exercise did not have a significant effect on the respiratory rate per minute (p=.890). On the other hand, wearing a mask during maximum load exercise test had a significant effect on cardiopulmonary fitness such as HR(p<.001, KF-AD, KF94 < NM), VE(p<.001, KF-AD, KF94 < NM), TV(p<.001, KF-AD, KF94 < NM), ToE(p<.05, KF-AD, KF94 < NM), VO2max(p<.001 KF-AD, KF94 < NM), and VT(p<.001, KF-AD, KF94 < NM). However, there were no significant differences depending on the type of mask. Considering the above results, wearing a mask affects the ventilation ability during maximum load exercise, reducing aerobic performance such as VO2max and VT. These results confirmed that after wearing face masks, it is necessary to reconsider the effect of the mask on the reset of exercise intensity and the measurement of aerobic performance.

A 54-862 MHz CMOS Direct Conversion transmitter for IEEE 802.22 Cognitive Radio Applications

Jongsik Kim,Seungsoo Kim,Jaewook Shin,Youngcho Kim,Hyunchol Shin 대한전자공학회 2008 대한전자공학회 워크샵 Vol.2008 No.9

An eco-friendly treatment of tannery wastewater using bioaugmentation with a novel microbial consortium.

Kim, In-Soo,Ekpeghere, Kaluibe,Ha, Shin-Young,Kim, Soo-Hyeon,Kim, Bong-Soo,Song, Bongkeun,Chun, Jongsik,Chang, Jae-Soo,Kim, Hong-Gi,Koh, Sung-Cheol Marcel Dekker 2013 Journal of environmental science and health. Part Vol.48 No.13

<P>A novel microbial consortium (BM-S-1) enriched from natural soils was successfully used to treat tannery wastewater from leather manufacturing industries in Korea on a pilot scale. The objective of this study was to determine whether augmentation with a novel microbial consortium BM-S-1could successfully treat the recalcitrant wastewater without chemical pre-treatment in a tannery wastewater treatment system. Chemical oxygen demand (COD), total nitrogen (TN) and total phosphorus (TP) were monitored for water quality. The microbial population dynamics were analyzed using pyrosequencing, and denitrifying bacteria were quantified using real-time PCR (RT-PCR). The removal efficiencies for COD, TN and TP were greater than 91%, 79%, and 90%, respectively. The dominant phyla in the buffering tank (B), primary aeration (PA), secondary aeration (SA) and sludge digestion tank (SD) were Proteobacteria, Firmicutes, Bacteroidetes, Planctomycetes and Deinococcus-Thermus. Cluster analysis based on the UniFrac distance of the species in the different stages showed that the PA is similar to the SA, whereas the B is similar to the SD. qPCR of the nosZ genes showed the highest abundance of denitrifiers in B, which was increased 734-fold compared to the influent (I). It was hypothesized that anaerobic denitrifiers and the diverse microbial community may play important roles in the biological treatment of tannery wastewater. This technology may also contribute to the full-scale treatment of industrial wastewater containing food processing wastewater and marine sediment with high organic content.</P>

Characteristics of silicon oxynitride films grown by using neutral-beams and inductively coupled plasma

Kim, Jongsik,Kim, Dae Chul,Kim, Young-Woo Elsevier 2017 THIN SOLID FILMS - Vol.642 No.-

<P><B>Abstract</B></P> <P>The characteristics of silicon oxynitride (SiON) films grown using neutral-beam and typical plasma-enhanced chemical vapor deposition methods are compared. Neutral-beam and plasma oxynitridation processes were performed using a nitrogen neutral beam at room temperature and a nitrogen plasma at 400°C, respectively, using the same deposition system. The neutral beam was generated via the surface neutralization of the ions produced by the inductively coupled plasma. The physical and electrical properties were measured using metal-insulator‑silicon structures. The plasma SiON films showed significant plasma-induced damage, while we demonstrate that the neutral beam method is suitable for growing SiON films at room temperature without plasma-induced damage or a high thermal budget.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Silicon oxynitride (SiON) films were grown. </LI> <LI> Neutral beam and typical plasma-enhanced chemical vapor deposition (PECVD) methods were used. </LI> <LI> The physical and electrical properties were measured for metal-insulator‑silicon structures. </LI> <LI> PECVD films had plasma-induced damage, which did not occur with neutral beam method. </LI> <LI> The latter is thus more suitable for room-temperature growth of SiON films. </LI> </UL> </P>

CR STRUCTURES AND THE MIZOHATA TYPE OPERATORS

KIM, JONGSIK,KIM, JUNG SOO,KIM, SUNG KI,KIM, DOHAN Korean Mathematical Society 1986 대한수학회논문집 Vol.1 No.1

고분자전해질 연료전지의 성능과 안정성 시험을 위한 단위전지의 시간 경과에 따른 모델링

김종식(Jongsik Kim),김필(Pil Kim),주지봉(Ji Bong Joo),김우영(Wooyoung Kim),이종협(Jongheop Yi) 한국청정기술학회 2008 청정기술 Vol.14 No.1

연료전지기술은 환경적으로 유해한 오염물질을 발생시키지 않으며 높은 에너지 밀도를 가지는 청정에너지기술이다. 특히 고분자전해질 연료전지(Polymer electrolyte membrane fuel cell, PEMFC)는 넓은 응용 분야로 인해 최근 큰 관심을 받고 있으며, 폭넓은 연구가 진행되고 있다. 본 연구에서는 단위전지 내 연료극(anode) 및 공기극(cathode) 촉매 층을 대상으로 고분자전해질연료전지의 운전시간 경과에 대한 성능변화 및 안정성을 예측하는 모델링을 수행하였다. 촉매층에서 발생하는 단위전지의 주요한 성능감소 원인으로 연료극에서의 일산화탄소 피독 현상을 고려하였다. 전지의 장기간 운전모델링 결과 연료극에 공급되는 기체 내의 일산화탄소 비율이 클수록 단위전지성능의 안정성이 크게 감소되는 것으로 나타났다. 또한 장기 운전 시 공기극의 느린 산소환원반응과 백금의 용해와 소결에 의해 전지의 성능이 감소되는 것으로 나타났다. 이들을 극복하는 방안으로 연료극에 공급되는 수소의 비율을 높이고 공기극의 촉매층 내에 있는 백금양을 높이는 것을 제안하고자 한다. There have been great attentions on polymer electrolyte membrane fuel cell (PEMFC) due to their advantageous characteristics such as zero emission of hazardous pollutant and high energy density. In this work, we evaluated degradation phenomena and stability of single cell performance via one dimensional single cell modeling. Here, CO poisoning on anode on anode was considered for cell performance degradation. Modeling results showed that the performance and stability were highly degraded with CO concentration in fuel gas. In addition, cell performance was reduced by slow oxygen reduction on cathode in long term operation. In order to overcome, it is required to increase ratio of hydrogen in the fuel gas of anode and high Pt loading contained in the cathodic catalyst layer.

Hierarchically Structured Core-Shell Design of a Lithium Transition-Metal Oxide Cathode Material for Excellent Electrochemical Performance

Shim, Jae-Hyun,Kim, Young-Hoon,Yoon, Han-Sol,Kim, Han-A,Kim, Ji-Soo,Kim, Jongsik,Cho, Nam-Hee,Kim, Young-Min,Lee, Sanghun American Chemical Society 2019 ACS APPLIED MATERIALS & INTERFACES Vol.11 No.4

<P>Tuning geometrical parameters of lithium-mixed transition-metal oxide (LiTM) cathode materials is a promising strategy for resource-efficient design of high-performance Li-ion batteries. In this paper, we demonstrate that simple and facile geometrical tailoring of the secondary microstructure of LiTM cathode materials without complex chemical modification or heterostructure engineering can significantly improve overall electrochemical performance of the active cathode materials. An optimized LiTM with a bimodal size distribution of primary particles inside the secondary particles exhibits a 53.8% increase in capacity at a high discharge rate (10 C) compared to a commercially available reference and comparable rate capability after 100 charge/discharge cycles. The key concept of this approach is to maximize the beneficial effects arising from the controlled sizes of primary particles. Multimodal/multiscale microscopic characterizations based on electron tomography and scanning transmission electron microscopy, combined with electron energy-loss spectroscopy and energy-dispersive X-ray spectroscopy from the atomic level to the microscale level, were employed to elucidate structural origins of enhanced battery performance. This study paves the way for the resource-efficient microstructure design of LiTM cathode materials to maximize capacity and stability via simple adjustment of processing conditions, which is advantageous for mass-production applications.</P> [FIG OMISSION]</BR>

Mori Folium water extract alleviates articular cartilage damages and inflammatory responses in monosodium iodoacetate-induced osteoarthritis rats

Jeong, Jin-Woo,Lee, Hye Hyeon,Kim, Jongsik,Choi, Eun-Ok,Hwang-Bo, Hyun,Kim, Hong Jae,Kim, Min Young,Ahn, Kyu Im,Kim, Gi-Young,Lee, Ki Won,Kim, Ki Young,Kim, Sung Goo,Hong, Su Hyun,Park, Cheol,Cha, Hee D.A. Spandidos 2017 MOLECULAR MEDICINE REPORTS Vol.16 No.4

<P>Mori folium, the leaf of <I>Morus alba</I> L. (Moraceae), has been widely used in traditional medicine for the treatment of various diseases. It has been recently reported that Mori folium possesses potential chondroprotective effects in interleukin (IL)-1β-stimulated human chondrocytes; however, its protective and therapeutic potential against osteoarthritis (OA) in an animal model remains unclear. In this study, as part of an ongoing screening program to evaluate the anti-osteoarthritic potential of Mori folium, the protective effects of a water extract of Mori folium (MF) on cartilage degradation and inflammatory responses in a monosodium iodoacetate (MIA)-induced OA rat model were evaluated. The results demonstrated that administration of MF had a tendency to attenuate the damage to articular cartilage induced by MIA, as determined by knee joint swelling and the histological grade of OA. The elevated levels of matrix metalloproteinases-13 and two bio-markers for the diagnosis and progression of OA, such as the cartilage oligomeric matrix protein and C-telopeptide of type II collagen, were markedly ameliorated by MF administration in MIA-induced OA rats. In addition, MF significantly suppressed the production of pro-inflammatory cytokines, including IL-1β, IL-6 and tumor necrosis factor-α. MF also effectively inhibited the expression of inducible nitric oxide (NO) synthase and cyclooxygenase-2, thus inhibiting the release of NO and prostaglandin E<SUB>2</SUB>. Although further work is required to fully understand the critical role and clinical usefulness, these findings indicate that MF may be a potential therapeutic option for the treatment of OA.</P>

THE STRUCTURE OF L(M, L)

KIM, JONGSIK Korean Mathematical Society 1973 대한수학회지 Vol.10 No.1

EXTENSION OF WEAKLY COMPACT OPERATORS

KIM, JONGSIK Korean Mathematical Society 1976 대한수학회지 Vol.13 No.2