단기 앙상블 예보에서 모형의 불확실성 표현

김세나(Sena Kim),임규호(Gyu-Ho Lim) 한국기상학회 2015 대기 Vol.25 No.1

The most objective way to overcome the limitation of numerical weather prediction model is to represent the uncertainty of prediction by introducing probabilistic forecast. The uncertainty of the numerical weather prediction system developed due to the parameterization of unresolved scale motions and the energy losses from the sub-scale physical processes. In this study, we focused on the growth of model errors. We performed ensemble forecast to represent model uncertainty. By employing the multi-physics scheme (PHYS) and the stochastic kinetic energy backscatter scheme (SKEBS) in simulating typhoon Rusa (2002), we assessed the performance level of the two schemes. The both schemes produced better results than the control run did in the ensemble mean forecast of the track. The results using PHYS improved by 28% and those based on SKEBS did by 7%. Both of the ensemble mean errors of the both schemes increased rapidly at the forecast time 84 hrs. The both ensemble spreads increased gradually during integration. The results based on SKEBS represented model errors very well during the forecast time of 96 hrs. After the period, it produced an under-dispersive pattern. The simulation based on PHYS overestimated the ensemble mean error during integration and represented the real situation well at the forecast time of 120 hrs. The displacement speed of the typhoon based on PHYS was closest to the best track, especially after landfall. In the sensitivity tests of the model uncertainty of SKEBS, ensemble mean forecast was sensitive to the physics parameterization. By adjusting the forcing parameter of SKEBS, the default experiment improved in the ensemble spread, ensemble mean errors, and moving speed.

중국인 학습자를 위한 과제 기반 플립 러닝 한국어 교육 방안―‘수업 구성 원리’와 ‘교사 역할’을 중심으로

김세나 ( Kim Sena ) 중국한국(조선)어교육연구학회 2019 한국(조선)어교육연구 Vol.14 No.-

Recently, there have been many studies on the methods and effectiveness of the Flipped Learning approach in education. KFL(Korean as a Foreign Language) has been also interested in the Flipped Learning with high expectations. This study has suggested that the Flipped Learning focused on task-activity could flip many parts of KFL in China. Above all, it is necessary to establish the ‘Principles of Instruction’ and the ‘teacher role’ for the Flipped Learning system so that it can be a sustainable Teaching-Learning method in KFL. This study emphasizes the role of Flipped Learning that could contribute to the Task-based Language Teaching, and explains the key components and principles for instruction. In addition, This suggests the ‘teacher role’ that should be flipped under a new system in KFL. This study is meaningful to KFL in China because it provides the effective teaching guideline for the Flipped Learning focused on Task-based Language Teaching.

콩의 폴리페놀, 피테이트 함량과 항산화능과의 관계

김미정(Mee Jeong Kim),송영주(YoungJu Song),김혜란(HyeRan Kim),이석룡(Seok Ryong Lee),석대은(Dai-Eun Sok),김세나(Sena Kim),김미리(Mee Ree Kim) 동아시아식생활학회 2009 동아시아식생활학회지 Vol.19 No.6

Bending Mode Vibration Control of a Flexible Shaft Supported by a Hybrid Air-foil Magnetic Bearing

Sena Jeong(정세나),Hyung Joon Ahn(안형준),Seung Jong Kim(김승종) 한국소음진동공학회 2009 한국소음진동공학회 학술대회논문집 Vol.2009 No.11

공기포일 자기 하이브리드 베어링으로 지지되는 연성 축의 휨 모드 진동 제어

정세나(Sena Jeong),안형준(Hyeongjoon Ahn),김승종(Seungjong Kim),이용복(Yongbok Lee) 한국트라이볼로지학회 2011 한국트라이볼로지학회지 (Tribol. Lubr.) Vol.27 No.2

Hybrid air-foil magnetic bearing integrates two oil free bearing technologies synergetically to adopt the strengths of two bearings with minimizing their weaknesses. This paper presents bending mode vibration control of a flexible shaft supported by the hybrid air-foil magnetic bearing. An experiment set-up of a flexible shaft supported by the hybrid air-foil magnetic bearing is built. In order to verify the effectiveness of the hybrid bearing, unbalance responses of the flexible shaft supported by three different bearings: air-foil, magnetic and hybrid bearings are compared. Effect of load sharing between air-foil and magnetic bearings are investigated through changing the control gain and the rotor center position of magnetic bearing. The experimental results shows that the hybrid bearing can control the bending mode vibration of the flexible shaft effectively and an optimal performance can be achieved with an appropriate load sharing between the air-foil and the magnetic bearings.

상업용 김치와 담금 배추김치의 발효에 따른 품질특성 변화

남동건,김세나,최용민,김영섭,양미란,한혜경,최애진,Nam, Dong-Geon,Kim, Sena,Choi, Youngmin,Jin, Yong-Xie,Yang, Mi-Ran,Han, Hye-Kyung,Choi, Ae-Jin 한국식품조리과학회 2017 한국식품조리과학회지 Vol.33 No.2

Purpose: The purpose of this study was to evaluate the folate contents and quality characteristics of commercial and fermented Kimchi and compare the correlation between folic acid and quality characteristics. Methods: The contents of total folate and quality characteristics were evaluated in 10 kinds of industrial and local Kimchi and nine kinds of other commonly consumed Kimchi. Changes in folate content and quality characteristics of Kimchi during 14 days of fermentation at $15^{\circ}C$ were compared. Results: Chungnam (L4) Kimchi had the lowest pH of 4.62, and acidity (0.57%) and salinity (3.26%) were highest compared to other areas. The content of total folate of D company (A) was the highest at $73.66{\mu}g/100g$. The content of total folate was significantly higher than those of Sesame leaf Kimchi (O9) and Young leafy radish Kimchi (O5) containing 65.77 and $62.82{\mu}g/100g$, respectively. The pH of fermented Kimchi decreased from 6.09 to 4.11 (p<0.05), and the acidity significantly increased (p<0.001) to 0.32-0.66%. Reducing sugar content decreased rapidly by 4 days and then slowly decreased (p<0.001). Total bacteria and lactic acid bacteria counts significantly increased (p<0.05) with fermentation period. Content of total folate was highest at $69.82{\mu}g/100g$ and $68.16{\mu}g/100g$ on days 0 and 2 of fermentation, after which it decreased to 77.6% at $15.61{\mu}g/100g$ on day 10 of fermentation. Conclusion: As a result, there was no definite trend regarding folate content in commercial Kimchi and other Kimchi. Young leafy radish, Chives, and Welsh onion Kimchi, which are rich in green leaves, are excellent folate source foods. The highest folate content of fermented Kimchi was identified on day 2 of fermentation. Therefore, it is recommended to use raw or immature Kimchi when using Kimchi as a folate source food.

콩의 종류 및 조리방법에 따른 단백질·아미노산 함량 변화

임정연,김상천,김세나,최용민,양미란,조인희,김행란,Im, Jeong Yeon,Kim, Sang-Cheon,Kim, Sena,Choi, Youngmin,Yang, Mi Ran,Cho, In Hee,Kim, Haeng Ran 한국식품조리과학회 2016 한국식품조리과학회지 Vol.32 No.5

Purpose: The objective of this study was to provide nutritional information (protein and amino-acid contents) of soybeans (Baktae, Seoritae, Huktae, and Seomoktae) with different cooking methods. Methods: Raw, boiled (in $100{\pm}15^{\circ}C$ of water for 4 hr), and fried (in a pan at $110{\pm}15^{\circ}C$ for $20{\pm}5min$) soybean samples were prepared. Contents of protein and amino acids were determined. Results: Protein content in raw Baktae, Seoritae, Huktae, and Seomoktae soybeans ranged from 361.0 to 386.8 mg/g. Protein contents differed according to cooking methods. They were higher in pan-fried beans (107.9-113.5%) than in raw or boiled soybeans (48.2-49.5%). A total of 18 amino acids were analyzed. Amino acid data sets were subjected to principle component analysis (PCA) to understand their differences according to soybean types and cooking methods. Bean samples could be distinguished better according to cooking method in comparison with bean types by principle component (PC1) and PC2. In particular, fried soybeans contained much higher levels of cystein. Other amino acids were the dominant in raw and boiled ones. On the other hand, the amounts of threonine, histidine, proline, arginine, tyrosine, lysine, tryptophan, and methionine were higher in raw bean samples than in cooked ones. Conclusion: The contents of amino-acids and proteins are more effected by different cooking methods in comparison with soybean types.

게임에서 결과/과정 초점 유형과 디바이스에 따른 동기와 수행 차이

김경일(Kyungil Kim),최연호(Yeonho Choi),문익현(Ik-hyun Moon),김세나(Sena Kim),신승원(Seungwon Shin),이나연(Nayeon Lee),홍석성(Seok-sung Hong) 한국자료분석학회 2023 Journal of the Korean Data Analysis Society Vol.25 No.6

Virtual reality(VR)게임이 등장하며 많은 사람들이 관심을 갖고, 다양한 분야에서 적절하게 활용하여 이를 유용하게 사용하고 있다. 그 중, 게임 분야에서는 초기 등장과 함께 많은 관심을 받았다. 기존의 게임 매체인 Computer screen(CS)와 비교하여 어떤 차이가 있을지 알아보고자 연구를 진행하였다. 게임의 두 매체(VR, CS)와 게임을 하는 사람들의 초점 유형(결과 초점, 과정 초점)이 동기와 수행에 어떠한 영향을 미치는지 확인하기 위해서 실제 게임을 활용하여 실험을 진행하였다. 초점 유형과 각 매체가 가지고 있는 특성, 다시 말해 각 매체를 활용하여 게임을 할 때, 게임을 수행하며 제공하는 정보나 가치가 초점과 일치할 때 동기와 수행이 높을 것으로 예상하였다. 연구 결과 VR에서 과정을 중점으로 게임을 하는 사람들이 결과를 중점으로 하는 사람들보다 더 좋은 기록을 보였다. 또한 자신의 기록 정도를 물어본 질문에서 과정 초점 참가자가 CS보다 VR에서 정확도가 떨어졌다. 정확도가 떨어진 VR 참가자 집단에서 더 좋은 기록을 보였다는 것은 이 결과가 매체의 차이와 심리적 상태를 같이 고려해야 한다는 점을 제안한다. With the advent of virtual reality (VR) games, many people are using them appropriately in various fields to fulfill their own interests. Among them, gaming field showed great interest toward VR upon its initial appearance. A study was carried out to find out the difference compared to the existing game device, Computer screen (CS). An experiment was conducted using an actual game to determine how both devices (VR, CS) and the type of focus induced (result focus, process focus) affect motivation and performance of the game player. It was expected that motivation and performance would be high when the type of focus and the characteristics of each device align, that is, when playing games using each device, the information or value provided while playing the game matched the focus. The results of the study showed that people who played games on VR with a focus on the process performed better than those who focused on the outcome. Additionally, when asked about their level of performance, process-focused participants were less accurate on VR than on CS. Nevertheless, better performance was shown on VR with lower accuracy on level of performance. Hence, these results suggest that the type of the device and psychological state of the player should be considered altogether.

농협 가공식품의 유통경로 체계화를 위한 판매대행센타 설립에 관한 사례

김상용(Sang Yong Kim),유창조(Chang Jo Yoo),김세나(Sena Kim),최진표(Jin Pyo Choi) 한국유통학회 2000 流通硏究 Vol.5 No.1

농협 중앙회 소속 조합단위들은 지역 농산물의 수매량을 늘리기 위한 목적으로 가공공장을 설립하였으나, 각 공장들이 개별조직의 개념으로 운영되어 영세성을 면하지 못하고 있고, 일반 기업체의 제품과의 경쟁력이 점정 상실되는 상황에 처해 있다. 이러한 상황에서 농협 중앙회는 농판매대행센타의 설립의 추진을 통하여 농협 조합단위에서 운영하고 있는 가공공장들의 판매체계를 간소화하고 유통경로의 체계화를 추진하고 있다. 본 보고서에서는 농협 중앙회가 판매대행센타의 설립을 을 추진하게 된 배경 및 추진 단계를 소개하고 판매대행센다의 설립 추진시 예상되는 문제점 및 해결방안을 점검하였다. 특히 농협은 비영리단체이기 때문에 일반 기업과는 다른 여러 가지 조직적인 문제점을 안고 있는데, 비영리단체에서도 마케팅 개념에 입각한 판매체계 및 유통경로의 체계화 추진이 가능함을 잘 보여주고 있다. Throughout the nation, each local Agricultural Cooperative (AC) has built its own agri-products processing factory in order to provide the steady demand source for the locally produced agri-products. However, each factory of AC has performed poorly with no competitive advantages against the national brands of private companies. Thus, from the perspective of the National Agricultural Cooperative Federation (NACF), the current situation of unorganized and inefficient management of the factories under the control of each local AC needs to be improved. In this case analysis, we introduce the problems of the AC factories and discuss the NACF's approach to solve the problems. In particular, given that AC as well as NACF are the non-profit organizations, it is worthwhile to pay special attention to the process of restructuring the system of distribution channels for the processed agri-products with the concept of marketing.

식생활 교육 전문 역량에 대한 중요도-수행도(IPA) 분석

이진영(Jin young Lee),김세나(Sena Kim),권용석(Yongseok Kwon),장희진(Hee Jin Jang) 한국지역사회생활과학회 2021 한국지역사회생활과학회 학술대회 자료집 Vol.2021 No.11