리튬 이온 전지용 실리콘 복합 음극 재료의 설계 및 공학

마지영(Jiyoung Ma),조재필(Jaephil Cho) 한국태양에너지학회 2021 한국태양에너지학회 학술대회논문집 Vol.2021 No.11

Micron-sized Fe–Cu–Si ternary composite anodes for high energy Li-ion batteries

Chae, Sujong,Ko, Minseong,Park, Seungkyu,Kim, Namhyung,Ma, Jiyoung,Cho, Jaephil The Royal Society of Chemistry 2016 ENERGY AND ENVIRONMENTAL SCIENCE Vol.9 No.4

<P>Nano-engineering of silicon anodes has contributed to the demonstration of a promising potential for high energy lithiumion batteries, through addressing the degradation of battery performance derived from severe volume changes during cycling. However, the practical use of nano-engineered silicon anodes is still stuck because of remaining challenges, such as the low tap density, poor scalability and inferior electrical properties. Herein, we successfully developed a new Fe-Cu-Si ternary composite (FeCuSi) by scalable spray drying and facile heat treatment. As a result, FeCuSi exhibited remarkable initial Coulombic efficiency (91%) and specific capacity (1287 mA h g(-1)). In order to exactly characterize the electrical properties of FeCuSi and directly compare them with industrially developed benchmarking samples such as silicon monoxide (SiO) and a silicon-metal alloy (Siw(2)Fe), both half-cell and full-cell tests were performed with high electrode density (1.6 g cc(-1)) and high areal capacity (3.4 mA h cm(-2)). Overall, FeCuSi outperformed the benchmarking samples in terms of discharge capacity and capacity retention in high mass loading for 300 cycles.</P>

한국 여자 청소년과 성인 여성의 혈청 철 영양상태 및 식품 섭취와 혈중 중금속 농도와의 상관성

김지영(Jiyoung Kim),신민서(Minseo Shin),김성희(Sunghee Kim),서지현(Jihyun Seo),마혜선(Hyesun Ma),양윤정(Yoon Jung Yang) 한국영양학회 2017 Journal of Nutrition and Health Vol.50 No.4

Purpose: This study examined and compared the associations of the iron status and food intake with the blood lead, mercury, and cadmium concentrations among Korean adolescent girls, premenopausal women, and postmenopausal women. Methods: The data from the 2010~2011 Korea National Health and Nutrition Examination Survey (KNHANES) was used. The subjects were classified into three groups: adolescent girls (n = 268), premenopausal women (n = 1,157), and postmenopausal women (n = 446). The iron status was assessed by hemoglobin, hematocrit, serum ferritin, and iron concentrations, as well as the total iron binding capacity (TIBC). The food intake was estimated by a food frequency questionnaire. Results: The blood heavy metal concentrations and poisoning rate in postmenopausal women were higher than in the other groups. The iron status in the adolescent girls and postmenopausal women was higher than that in the premenopausal women. In the adolescent girls, the iron status was inversely associated with the blood cadmium concentration. The dairy food intake was inversely related to the blood lead and cadmium concentrations. In premenopausal women, the iron status was inversely associated with the cadmium concentrations. The fish and shellfish food intakes were positively associated with the mercury concentrations. In postmenopausal women, the iron status was positively associated with the mercury and cadmium concentrations. Fast foods and fried foods were inversely associated with the lead concentration. Conclusion: The premenopausal women showed a lower iron status than the adolescent girls and postmenopausal women. The associations of the iron status with the blood heavy metal concentrations were different among the adolescent girls, premenopausal women, and postmenopausal women. In addition, the relationships of the food intakes with the blood heavy metal concentrations differed among adolescent girls, premenopausal women, and postmenopausal women. Further studies will be needed to confirm these findings.

A Multi-Path Support for Mobile IP with the Hierarchical Architecture

Youngsik Ma,Donghyun Chae,Wonjong Noh,Jiyoung Lee,Yeonjoong Kim,Sunshin An 한국정보과학회 2002 한국정보과학회 학술발표논문집 Vol.2002 No.1

인터넷 환경에서의 차세대 지능망 적용을 위한 SCP설계 및 구현

이지영(Jiyoung Lee),김연중(Yeon-Joong Kim),마영식(Youngsik Ma),김동호(Dongho Kim),안순신(Sunshin An) 한국정보과학회 2001 정보과학회 컴퓨팅의 실제 논문지 Vol.7 No.4

지능망은 사용자의 다양한 서비스 요구에 부응하여 여러 가지 서비스를 보다 간단히 개발 적용시키는 것을 목적으로 한다. 이에 따라 차세대 지능망 플랫폼은 빠른 서비스 처리, 다양한 서비스의 동적 적용 등이 가능한 시스템이 되어야 한다. 본 논문에서는 차세대 지능망 플랫폼의 핵심이 되는 SCP(Service Control Point)를 설계하고 구현하였으며, 특히, 설계시 확장성, 동적 서비스 분배 및 인터넷환경을 고려한 빠른 서비스 처리 등의 지원에 중점을 두었다. 이 SCP는 시스템 운용을 담당하는 전용 커널, 전체 서비스를 관리하는 서비스 관리자, 각 서비스 별로 SLPI(Service Logic processing Program Instance)를 관리하는 SLPI관리자 등으로 구성되어 있으며, 사용자 요청은 각각의 SLPI들에 의해 처리된다. 또한, 구현된 SCP상에서 동작하는 서비스의 손쉬운 생성을 지원하는 SCE(Service Creation Environment)환경을 제시하고, 이를 이용한 서비스 적용 예도 보인다. 현재 구현된 모든 구성 요소들은 유선 인터넷 환경을 고려하여 설계되었으며, 향후 IMT-2000 환경으로의 적용도 가능할 수 있도록 각 부분별로 구분하여 설계하였다. Intelligent Network (IN) is an architectural framework for the rapid and uniform provision of advanced services. Therefore, Next-generation IN platform should support fast service handling, the dynamic adaptation of various services according to various requirements of users. In this paper, we design and implement the Service Control Point (SCP) that is based on the Internet environment. Especially, we consider the service flexibility, the dynamic distribution of service and propose a set of mechanisms to optimize the performance of this platform. This SCP consists of the platform kernel to control internal operations, the service manager to control all of services, SLPI (Service Logic processing Program Instance) manager to manage each service, and SLPI to handle service interaction. In addition, we propose the Service Creation Environment (SCE) to create easily services on the implemented platform and show the example of Call Forwarding service operated on this platform.

지역성기반 중국 현대 건축 디자인 특성 연구

마동칭(Ma DongQing),윤지영(Yoon Jiyoung),장징위(Zhang JingYu) 한국실내디자인학회 2018 한국실내디자인학회 학술대회논문집 Vol.20 No.3

This study is to explore the characteristics of contemporary Chinese architecture from the aspects of the regionalism of environment, culture and technology. Four cases of contemporary Chinese architecture which won the world-wide famous were selected and analyzed. The results are the followings; First, the regionalism of environment emphasizes the building"s response to the regional environment (topography, climate and regional landscape). Second, the regionalism of culture reflects as the relevance between architecture and community structure, economic patterns, folk customs and other social factors of the region. Third, the regionalism of technology requires the coordination of construction process, structure form, materials and other contents of architecture with the regional environment and culture, and emphasizes the suitability of technology. Environment, culture and technology determine that the regionalism of contemporary Chinese architecture is not purely the meaning at the formal level, but explores the underlying causes.

Quantification of Pseudocapacitive Contribution in Nanocage‐Shaped Silicon-Carbon Composite Anode

Son, Yeonguk,Ma, Jiyoung,Kim, Namhyung,Lee, Taeyong,Lee, Yoonkwang,Sung, Jaekyung,Choi, Seong‐,Hyeon,Nam, Gyutae,Cho, Hyeyoung,Yoo, Youngshin,Cho, Jaephil Wiley 2019 ADVANCED ENERGY MATERIALS Vol.9 No.11

한국 성인의 체질량 지수에 따른 비만도와 주관적 체형인식 간의 차이가 영양소 섭취와 체중조절 및 정신건강에 미치는 영향

서지현(Seo, Jihyun),마혜선(Ma, Hyesun),김성희(Kim, Sunghee),김지영(Kim, Jiyoung),신민서(Shin, Minseo),양윤정(Yang, Yoon Jung) 한국영양학회 2016 Journal of Nutrition and Health Vol.49 No.3

본 연구는 제5기 국민건강영양조사를 이용하여 만 19~64세 성인 10,608명을 대상으로 BMI를 기준으로 분류한 체형과 주관적 체형인식의 차이를 기준으로 실제 체형보다 마르게 인식하는 RL군, 실제 체형을 올바르게 인식하는 RA군과 실제체형보다 비만하다고 인식하는 RH군으로 분류하여 각 그룹의 영양소 섭취, 체중조절 여부, 정신건강상태를 비교하였다. 1) RH군의 비율은 19~29세, 30~49세, 50~64세에서 남자는 12.1%, 9.5%, 10.0%였고, 여자는 31.2%, 29.0%, 20.3%로 여자에서 RH군의 더 비율이 높았고, RL군의 비율은 남자 19~29세, 30~49세, 50~64세에서 26.0%, 24.2%, 28.8%였고, 여자는 3.9%, 5.7%, 14.6%로 남자에서 RL군의 비율이 더 높았다. 2) 남녀 연령대별 BMI에서 남자 19~29세, 30~49세의 평균 BMI는 RA군이 가장 높고 RH군, RL군 순위였으며 50~64세에선 RL군이 가장 낮았다. 여자 19~29세에서는 RL군이 가장 낮았으며, 30~49세, 50~64세에선 RA군이 가장 높고 RH군, RL군 순이었다. 3) 남자의 경우 19~29세에서 탄수화물 섭취량은 RH군이 가장 낮게 섭취하였다. 여자는 30~49세에서 총에너지 섭취량은 실제체형보다 비만하게 인식하는 RH군이 에너지 섭취가 가장 낮았으며 RL군이 가장 많이 섭취했다. 여자 30~49세와 50~64세에서 탄수화물 섭취량이 RH군에서 가장 낮았고 총에너지 섭취량에 따른 탄수화물 섭취비율 또한 30~49세에서 실제체형보다 비만하게 인식하는 RH군에서 가장 낮아 실제체형보다 비만하게 인식하였을 때 탄수화물 섭취량이 적었으며 이로 인해 에너지 섭취량이 적었다. 4) 남자 50~64세를 제외한 남녀 모든 연령대에서 실제체형보다 비만하게 인식하는 RH군이 체중 감량 시도를 가장 많이 한 것을 알 수 있고, 남자 19~29세, 30~49세, 전 연령대의 여자에서 실제체형보다 비만하게 인식하는 RH군에서 체중이 증가한 경우가 가장 적었지만, 주별 중등도 운동일수에는 차이가 없어서 체형인식과 운동량은 관련이 없었다. 5) 남자 19~29세에서 실제체형보다 비만하게 인식하는 RH군이 우울감을 느낀 비율이 높았지만, 남자 50~64세에서는 실제체형보다 마르게 인식하는 RL군이 우울감 경험비율과 스트레스가 높아 체형인식에 따른 우울감은 남성에서 연령별로 차이를 보였다. 결론적으로 본 연구를 통해 성별과 연령에 따라 다소 차이가 있지만 실제체형보다 자신을 비만하다고 인식할 때 탄수화물의 섭취를 줄이고, 체중조절을 더 시도하며, 젊은 남성들에서 우울감 경험률이 높음을 알 수 있었다. 이에 따라 올바른 신체상을 확립하기 위해선 마른 몸매 선호에 대한 왜곡된 사회문화적 분위기를 개선하고 자신의 체형에 대한 올바른 인식이 필요함을 확인하였다. Purpose: The objective of this study was to examine the effect of the body shape discordance, the difference between true body type based on body mass index (BMI) and self-recognized body image, on nutrient intake, weight control attempt, and mental health in Korean adults. Methods: Subjects were persons aged 19~64 years (4,382 men and 6,226 women) who participated in the 2010~2012 Korea National Health and Nutrition Examination Survey. Subjects were categorized as RL (Group recognized as lighter than BMI criteria), RA (Group with agreement between BMI criteria and self-recognized body image), and RH (Group recognized as heavier than BMI criteria) according to the difference between actual body type based on BMI and self-recognized body image. Results: Means of BMI in RH groups were lower than or equal to that of RA groups in all groups. No significant differences in total energy intake were observed among the three groups in men, but total energy intake was higher in the RL group than in the RH group in 30~49 year old women. Proportion of carbohydrate was the highest in the RL group among 30~49 year old women. RH groups paid more attention to weight control and had less weight gain than other groups. Higher proportions of depressive symptoms were reported in the RH group in 19~29 year old men, while a higher proportion of depressive symptoms were reported in the RL group in 50~64 year old men. Conclusion: The current findings suggest an association of perceiving body shape with energy intake, weight control attempt, or depressed mood in some age groups. Body image perception can influence eating, weight control attempt, and depressed mood, therefore proper body image perception should be established in Korean adults.

양파농가의 공동체의식이 참여만족에 미치는 영향 분석

이정세 ( Lee Jungse ),마지영 ( Ma Jiyoung ),이남수 ( Lee Namsoo ),백경문 ( Baek Koungmoon ),장동헌 ( Jang Dong-heon ) 한국농촌계획학회 2021 농촌계획 Vol.27 No.1

This study analyzed the effect of the farm’s sense of community on participation satisfaction by participating in the contract cultivation of onions. To this end, we investigated the participation satisfaction with the sense of community’s emotional connection, fulfillment of need, membership, and influence. According to the analysis of the sense of community of onion farmers, the definition of need, membership, and influenced participation satisfaction and were statistically significant. It was also shown to affect sense of community in the order of membership, Influence, fulfillment of need, and emotional connection. Therefore, it is necessary to form a continuous relationship with the leader and Nonghyup, to lead to improved farm income, induce pride as a member of participating farmers, and form a positive perception among onion farmers.

Triboelectric-Based Film-Type Soft Robot Driven via Low-Frequency Mechanical Stimuli

Sungho Ji,Jaehee Shin,Jiyoung Yoon,Jung-Hwan Youn,Jihyeong Ma,Ki-Uk Kyung,Duck Hwan Kim,Hanchul Cho,Jinhyoung Park 한국정밀공학회 2023 International Journal of Precision Engineering and Vol.10 No.4

Triboelectric nanogenerators (TENGs) have received considerable attention owing to their ability to harvest energy from the environment. They can be effectively used as a self-generating power source to drive low-power devices. Compared with other energy harvesting technologies, the energy conversion efficiency is much higher, but the current output is low—only enough to drive an existing rotor-type motor. In this study, we designed a film-type soft robot that can produce high-voltage, low-power, triboelectric output without using a motor. Polyvinylidene fluoride (PVDF) film was used as the actuator for the soft robot. We designed a resonance structure to increase the movement of the soft robot driven by low-frequency triboelectric output. A driving test was performed by simulating the shape of butterfly wings and an inch-worm. When the butterfly-shaped PVDF film robot simulated the flapping motion of wings using the resonance structure parameter design, it was able to generate 2.5 times greater movement than the model without the resonance structure. In addition, the artificial inch-worm soft robot optimized for the TENG input was fabricated by applying the parameter design method to the PVDF film. We developed and tested a self-powered, intelligent soft robot that can be driven by low-frequency mechanical stimuli. This study can help extend the application of triboelectric generators.