Control of Local Magnetic Field of Ferromagnetic Nano Dot Array

Jooyoung Seo,Seonghoon Shim,Joonyeon Chang,Eunkyu Kim,A.A. Fraerman,V.L. Mironov 한국자기학회 2007 한국자기학회 학술연구발표회 논문개요집 Vol.- No.-

Façade cleaning robot with a manipulating and sensing devices equipped on a gondola

ChangKook Seo(서창국),Garam Park(박가람),Hobyeong Chae(채호병),Jooyoung Hong(홍주영),Jiseok Lee(이지석),Kyungmin Kim(김경민),Taegyun Kim(김태균),Hwa Soo Kim(김화수),TaeWon Seo(서태원) 대한기계학회 2020 대한기계학회 춘추학술대회 Vol.2020 No.12

AutoTP : 테스트 프로세스 자동 생성 도구

서주영(Jooyoung Seo),최병주(Byoungju Choi) 한국정보과학회 2001 정보과학회 컴퓨팅의 실제 논문지 Vol.7 No.4

소프트웨어 프로세스에 관한 표준을 각 프로젝트에서 이용하기 위해서 개발 도메인에 맞도록 테일러링하는 작업이 필요하다. 그러나 기존의 테일러링 작업은 체계적이지 않고, 개발 도메인과 방법론의 분석 없이는 불가능하며 유사한 다른 프로젝트로의 적용도 쉽지 않다. 본 논문에서는 “컴포넌트 기반 개발 개념을 활용한 테일러링 방안”을 기반으로한 체계적인 테일러링 단계와 테스트 프로세스 생성 자동화 알고리즘을 제안하고, XML을 이용하여 구현한 “테일러링 방안의 자동화 도구, AutoTP"를 제안한다. AutoTP 사용자는 프로세스 표준이나 방법론과 도메인을 분석하는 등의 작업 없이도 특정 개발 도메인에 적합한 테스트 프로세스를 자동생성할 수 있다. Utilizing standards for software process to a specific project requires a tailoring process to meet the development domain. However, the existing tailoring schemes are not systematical and possible to use without analyzing the methodology and development domain. Also, it is not quite easy to apply them to similar projects. This paper includes: 1) systematical tailoring steps and 2) an automatic algorithm for generating test process based on "a scheme of tailoring process using the component-based development paradigm"; 3)"an automation tool for tailoring, AutoTP"which is derived from XML techniques. Users can generate a tailored test process through our AutoTP automatically without analyzing standards, methodology and domain.

CMMI기반의 테스트 프로세스 개선 프레임워크와 단계적 개선방안

서주영(Jooyoung Seo),최병주(Byoungu Choi) 한국정보과학회 2005 정보과학회지 Vol.23 No.3

임베디드 소프트웨어 테스트를 개선하기 위한 에뮬레이터 기반 인터페이스 테스트 도구

서주영(Jooyoung Seo),최병주(Byoungju Choi) 한국정보과학회 2008 정보과학회 컴퓨팅의 실제 논문지 Vol.14 No.6

임베디드 시스템은 어플리케이션, OS 커널, 디바이스 드라이버, HAL, 하드웨어와 같은 이질적 계층들이 매우 밀접히 결합되어 있다. 임베디드 시스템은 제품 목적과 탑재된 하드웨어에 따라 맞춤 제작된다. 또한 점점 짧아지는 제품 주기 때문에 여러 업체의 소프트웨어, 하드웨어가 불안정한 상태에서 통합된다. 따라서 모든 계층에 결함 발생 확률이 높다. 임베디드 소프트웨어 개발자는 자신의 코드를 결함이 내재된 다른 계층들과 통합된 상태에서 테스트하며, 이 때문에 테스트해야 할 모든 영역을 테스트하였는지, 자신의 코드가 잘못된 건지, 통합된 다른 소프트웨어나 하드웨어에 문제가 있는 건 아닌지를 확신하기 힘들다. 본 논문은 임베디드 소프트웨어 개발자가 다양한 계층에 내재된 결함 위치와 원인을 추적할 수 있도록 하는 임베디드 소프트웨어 인터페이스 테스트 방안과 이를 구현한 자동화 도구 Justitia를 제안한다. 제안하는 기술은 개발자를 돕기위한 이뮬레이터를 이용한 디버깅을 전문적인 테스팅으로 승화시킨 자동화 방안이다. Embedded system is tightly coupled with heterogeneous layers such as application, OS kernel, device driver, HAL and hardware. Embedded system is customized for the specific purpose and hardware. In addition, the product cycle is so fast that software and hardware, which are developed by several vendors, are integrated together under unstable status. Therefore, there are lots of possibilities of faults in all layers. Because embedded software developers test their codes integrated with faulty layers, they cannot confirm ‘whether testing of every aspects was completed, their code was failed, or integrated software/hardware has some problems’. In this paper, we propose an embedded software interface test method and a test tool called Justitia for detecting faults and tracing causes in the interface among heterogeneous layers. The proposed technique is an automated method which improves debugging upto professional testing using an emulator for helping developer.

Surface mass balance contributions to acceleration of Antarctic ice mass loss during 2003-2013

Seo, Ki-Weon,Wilson, Clark R.,Scambos, Ted,Kim, Baek-Min,Waliser, Duane E.,Tian, Baijun,Kim, Byeong-Hoon,Eom, Jooyoung American Geophysical Union 2015 Journal of geophysical research. JGR. Earth surfac Vol.120 No.5

<P> Recent observations from satellite gravimetry (the Gravity Recovery and Climate Experiment (GRACE) mission) suggest an acceleration of ice mass loss from the Antarctic Ice Sheet (AIS). The contribution of surface mass balance changes (due to variable precipitation) is compared with GRACE-derived mass loss acceleration by assessing the estimated contribution of snow mass from meteorological reanalysis data. We find that over much of the continent, the acceleration can be explained by precipitation anomalies. However, on the Antarctic Peninsula and other parts of West Antarctica, mass changes are not explained by precipitation and are likely associated with ice discharge rate increases. The total apparent GRACE acceleration over all of the AIS between 2003 and 2013 is -13.6 ± 7.2 Gt/yr<SUP>2</SUP>. Of this total, we find that the surface mass balance component is -8.2 ± 2.0 Gt/yr<SUP>2</SUP>. However, the GRACE estimate appears to contain errors arising from the atmospheric pressure fields used to remove air mass effects. The estimated acceleration error from this effect is about 9.8 ± 5.8 Gt/yr<SUP>2</SUP>. Correcting for this yields an ice discharge acceleration of -15.1 ± 6.5 Gt/yr<SUP>2</SUP>. </P>

Necessary and sufficient conditions for the asymmetric synthesis of chiral amines using ω‐aminotransferases

Seo, Joo‐,Hyun,Kyung, Dohyun,Joo, Keehyoung,Lee, Jooyoung,Kim, Byung‐,Gee Wiley Subscription Services, Inc., A Wiley Company 2011 Biotechnology and bioengineering Vol.108 No.2

<P><B>Abstract</B></P><P>The half reactions of ω‐aminotransferase (ω‐AT) from <I>Vibrio fluvialis</I> JS17 (ω‐AT<I>Vf</I>) were carried out using purified pyridoxal 5′‐phosphate‐enzyme (PLP‐Enz) and pyridoxamine 5′‐phosphate‐enzyme (PMP‐Enz) complexes to investigate the relative activities of substrates. In the reaction generating PMP‐Enz from PLP‐Enz using <SMALL>L</SMALL>‐alanine as an amine donor, <SMALL>L</SMALL>‐alanine showed about 70% of the initial reaction rate of (<I>S</I>)‐α‐methylbenzylamine ((<I>S</I>)‐α‐MBA). However, in the subsequent half reaction recycling PLP‐Enz from PMP‐Enz using acetophenone as an amine acceptor, acetophenone showed nearly negligible reactivity compared to pyruvate. These results indicate that the main bottleneck in the asymmetric synthesis of (<I>S</I>)‐α‐MBA lies not in the amination of PLP by alanine, but in the amination of acetophenone by PMP‐Enz, where conformational restraints of the enzyme structure is likely to be the main reason for limiting the amine group transfer from PMP‐Enz to acetophenone. Based upon those half reaction experiments using the two amino acceptors of different activity, it appears that the relative activities of the two amine donors and the two acceptors involved in the ω‐AT reactions can roughly determine the asymmetric synthesis yield of the target chiral amine compound. Predicted conversion yields of several target chiral amines were calculated and compared with the experimental conversion yields. Approximately, a positive linear correlation (Pearson's correlation coefficient = 0.92) was observed between the calculated values and the experimental conversion yields. To overcome the low (<I>S</I>)‐α‐MBA productivity of ω‐AT<I>Vf</I> caused by the possible disadvantageous structural constraints for acetophenone, new ω‐ATs showing higher affinity to benzene ring of acetophenone than ω‐AT<I>Vf</I> were computationally screened using comparative modeling and protein‐ligand docking. ω‐ATs from <I>Streptomyces avermitilis</I> MA‐4680 (SAV2612) and <I>Agrobacterium tumefaciens</I> str. C58 (Atu4761) were selected, and the two screened ω‐ATs showed higher asymmetric synthesis reaction rate of (<I>S</I>)‐α‐MBA and lower (<I>S</I>)‐α‐MBA degradation reaction rate than ω‐AT<I>Vf</I>. To verify the higher conversion yield of the variants of ω‐ATs, the reaction with 50 mM acetophenone and 50 mM alanine was performed with coupling of lactate dehydrogenase and two‐phase reaction system. SAV2612 and Atu4761 showed 70% and 59% enhanced yield in the synthesis of (<I>S</I>)‐α‐MBA compared to that of ω‐AT<I>Vf</I>, respectively. Biotechnol. Bioeng. 2011;108: 253–263. © 2010 Wiley Periodicals, Inc.</P>

Study of Rocker-Bogie typed Mobile Robot for Driving, Climbing and Standing Upright

Eunho Seo,Jooyoung Chun,Hunkeon Ko,Sangin Park,Dong Jin Hyun 제어로봇시스템학회 2021 제어로봇시스템학회 국제학술대회 논문집 Vol.2021 No.10

This paper studies a mobile platform system to provide a service for a large range of regions. The coverage of large service region is recently required while the service robot market is rapidly increased. Therefore, Regions of delivery/patrol/surveillance/inspection services started to include outdoor terrains as well as indoor environments. Therefore, mobile robots have to adapt uneven terrains and overcome obstacles. In this paper, we introduce a rocker-bogie typed mobile robot which is able to provide this required capability. The robot has six active driving wheels, two degrees of freedom (DoFs) for active steering, and 2 DoFs for active bogie. The linear dynamic model was derived, and practically the values for normal and traction forces are calculated through the simple pseudo-inverse technique. The compensation algorithm is added to achieve minimal friction on the bogie axis, which leads to all wheel contact with the ground through the adaptation to uneven terrains. Also, the calculated traction force is distributed to ground contact wheels based on sensor estimation. In the experiment, upright-standing and climbing a curb were demonstrated. Especially, the upright posture of the robot was verified to be controlled based on Linear Quadratic Regulator (LQR) optimization controller using inverted pendulum model.

Fault-Tolerance 기능을 갖는 HA NAS 시스템의 설계 및 구현

김주영(JooYoung Kim),박준희(JoonHee Park),권혁빈(HyuckBin Kwon),서희정(HeeJeong Seo),정영준(YoungJun Chung) 한국정보과학회 2004 한국정보과학회 학술발표논문집 Vol.31 No.2Ⅰ

최근 업무에 컴퓨터를 이용하는 사례가 늘어나고 각종 건텐츠 서비스업계가 발전하면서 독립적인 파일 서버 기능 만을 처리하도록 만든 네트워크 저장장치인 NAS(Network Attached Storage)의 이용이 점차 증가하는 추세에 있다. NAS 는 기존 파일 서버의 문제점을 보완하면서 이기종 플랫폼간의 파일 공유, 스토리지 확장성, 관리 용이성 등을 특징으로 한다. 그러나 NAS 시스템에 장애가 발생할 경우에는 막대한 경제적인 손실이 발생하게 된다. 따라서 본 논문에서는 NAS 시스템 장애가 발생하였을 때, 효율적으로 장애를 복구할 수 있는 HA(High Availability) NAS 시스템을 설계 및 구현하고, 다양한 장애 상황에서 NAS를 이용하는 서비스가 중단없이 제공되는 것을 확인하였다.

Estimation of Amazon River discharge based on EOF analysis of GRACE gravity data

Eom, Jooyoung,Seo, Ki-Weon,Ryu, Dongryeol Elsevier 2017 Remote sensing of environment Vol.191 No.-

<P><B>Abstract</B></P> <P>River discharge is a critical component for understanding hydrological processes and sustainable management of water resources. The importance of discharge observation has increased due to its potential extreme variation resulting from the projected climate change and stronger variability of precipitation and temperature in some large basins. However, inherent difficulties in ground-based observations and decreasing number of gauge stations hinder accurate measurement of global river discharge and its spatio-temporal variations. Various remote sensing methods have been examined as alternatives, however, they require ground measurements to convert their proxy measurements into the actual river discharge. In this study, we estimate the discharge at the Óbidos station and the mouth of the Amazon basin using the water storage variations derived from GRACE gravity data without relying on any auxiliary ground observations. We extract the water mass signal along the main stem of the river by applying the Empirical Orthogonal Function (EOF) for water storage variations over the basin. The relative water storage variations along the main stem derived from the EOF decomposition are highly correlated with in-situ discharge at the Óbidos. However, in high water season, the GRACE-based discharge is estimated larger than the in-situ observations, and the difference is particularly significant during the 2009 extreme flood season. We argue that the in-situ river discharge in 2009 was underestimated due to the missed water volume for the flow detouring around the Óbidos gauge station during the high-flow event. Net river discharge of the Amazon Basin to Atlantic Ocean is also estimated, and its annual discharge is about 23% larger than that of the Óbidos. In particular, 2009 river discharge to Atlantic Oceans is estimated as 1050Gton.</P> <P><B>Highlights</B></P> <P> <UL> <LI> We estimate river discharge at the Óbidos station using GRACE. </LI> <LI> Discharge from GRACE is larger than that from in-situ observation during flooding. </LI> <LI> We argue that in-situ observation missed some flooding flow. </LI> <LI> River discharge at the Amazon Basin mouth is also estimated for the first time. </LI> </UL> </P>