슬라이딩 윈도우를 활용한 침입탐지시스템에서의 범주형 정보의 활용과 이기종 간 데이터의 복합적 활용 방법

박현재(Park Hyunjae),최영준(Choi Young-June) 한국통신학회 2022 한국통신학회 학술대회논문집 Vol.2022 No.6

모바일 웹 페이지 로딩에서 동적 관리 기법

박현재(Hyunjae Park),최영준(Youngjune Choi) 한국정보과학회 2015 정보과학회논문지 Vol.42 No.12

모바일 기기의 성능은 점진적으로 증가하여 멀티코어를 사용하는 고성능의 CPU를 장착한 스마트폰이 일상화 되었다. 그러나 고성능 기기가 사용하는 전력의 소모량을 배터리의 용량이 따라가지 못하므로 전력 관리를 위한 성능 제어가 필수적이 되었다. 이에 DVFS와 같은 Linux 기반의 전력 관리 방안이 연구되고 있으나, 동적으로 자원 요구량의 변화가 심하고 사용자의 입력이 불규칙적인 모바일 기기의 특성으로 인한 한계가 존재한다. 본 연구에서는 DVFS와 같은 기존 Linux 기반의 전력 관리 방안이 웹페이지 로딩에 있어 부족한 점을 보완하여 사용자 반응성을 유지하면서 전력 소모를 줄이는 방법으로 네트워크를 통해 연산에 필요한 데이터를 받을 때까지 CPU의 동작 Frequency을 제한하는 방안을 제안하였다. 또한, 어플리케이션 수준에서의 구현을 통하여 웹페이지 로딩 시의 전력 소모가 감소함을 확인하였다. As the performance of mobile devices has increased, high-end multicore CPUs have become the norm in smartphones. However, such high performance devices are exposed to the problem of battery depletion due to the energy consumption caused by software performance, and despite increases in battery capacity. The required resources are dynamic and varied, and further user interaction is highly random; thus, Linux-based power management such as DVFS is needed to fulfill requirements. In order to reduce power consumption, we propose a method to restrict the CPU frequency of data download while maintaining user reactivity. This can supplement the weakness of existing Linux-based power management techniques like DVFS in relation to webpage loading. Through the implementation of our method at the application level, we confirm that energy consumption from webpage loading is reduced.

3-Input/1-Output Logic Implementation Demonstrated by DNA Algorithmic Self-Assembly

Cho, Hyunjae,Mitta, Sekhar Babu,Song, Yongwoo,Son, Junyoung,Park, Suyoun,Ha, Tai Hwan,Park, Sung Ha American Chemical Society 2018 ACS NANO Vol.12 No.5

<P>Although structural DNA nanotechnology is a well-established field, computations performed using DNA algorithmic self-assembly is still in the primitive stages in terms of its adaptability of rule implementation and experimental complexity. Here, we discuss the feasibility of constructing an <I>M</I>-input/<I>N</I>-output logic gate implemented into simple DNA building blocks. To date, no experimental demonstrations have been reported with <I>M</I> > 2 owing to the difficulty of tile design. To overcome this problem, we introduce a special tile referred to as an operator. We design appropriate binding domains in DNA tiles, and we demonstrate the growth of DNA algorithmic lattices generated by eight different rules from among 256 rules in a 3-input/1-output logic. The DNA lattices show simple, linelike, random, and mixed patterns, which we analyze to obtain errors and sorting factors. The errors vary from 0.8% to 12.8% depending upon the pattern complexity, and sorting factors obtained from the experiment are in good agreement with simulation results within a range of 1-18%.</P> [FIG OMISSION]</BR>

Treated chronic hepatitis B is a good prognostic factor of diffuse large B-cell lymphoma

Jeayeon Park,Sung Won Chung,Yun Bin Lee,Hyunjae Shin,Moon Haeng Hur,Heejin Cho,Min Kyung Park,Jeonghwan Youk,Ji Yun Lee,Jeong-Ok Lee,Su Jong Yu,Yoon Jun Kim,Jung-Hwan Yoon,Tae Min Kim,Jeong-Hoon Lee 대한간학회 2023 Clinical and Molecular Hepatology(대한간학회지) Vol.29 No.3

Background/Aims: Chronic hepatitis B (CHB) is a risk factor for non-Hodgkin lymphoma (NHL). Our recent study suggested that antiviral treatment may reduce the incidence of NHL in CHB patients. This study compared the prognoses of hepatitis B virus (HBV)-associated diffuse large B-cell lymphoma (DLBCL) patients receiving antiviral treatment and HBV-unassociated DLBCL patients. Methods: This study comprised 928 DLBCL patients who were treated with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) at two referral centers in Korea. All patients with CHB received antiviral treatment. Time-to-progression (TTP) and overall survival (OS) were the primary and secondary endpoints, respectively. Results: Among the 928 patients in this study, 82 were hepatitis B surface antigen (HBsAg)-positive (the CHB group) and 846 were HBsAg-negative (the non-CHB group). The median follow-up time was 50.5 months (interquartile range [IQR]=25.6–69.7 months). Multivariable analyses showed longer TTP in the CHB group than the non-CHB group both before inverse probability of treatment weighting (IPTW; adjusted hazard ratio [aHR]=0.49, 95% confidence interval [CI]=0.29–0.82, P=0.007) and after IPTW (aHR=0.42, 95% CI=0.26–0.70, P<0.001). The CHB group also had a longer OS than the non-CHB group both before IPTW (HR=0.55, 95% CI=0.33–0.92, log-rank P=0.02) and after IPTW (HR=0.53, 95% CI=0.32–0.99, log-rank P=0.02). Although liver-related deaths did not occur in the non-CHB group, two deaths occurred in the CHB group due to hepatocellular carcinoma and acute liver failure, respectively. Conclusions: Our findings indicate that HBV-associated DLBCL patients receiving antiviral treatment have significantly longer TTP and OS after R-CHOP treatment than HBV-unassociated DLBCL patients.

초등학생의 분수와 분수 연산에 대한 이해 양상

박현재 ( Park Hyunjae ),김구연 ( Kim Gooyeon ) 한국수학교육학회 2018 수학교육 Vol.57 No.4

This study examines how elementary students understand fractions with operations conceptually and how they perform procedures in the division of fractions. We attempted to look into students’ understanding about fractions with divisions in regard to mathematical proficiency suggested by National Research Council (2001). Mathematical proficiency is identified as an intertwined and interconnected composition of 5 strands- conceptual understanding, procedural fluency, strategic competence, adaptive reasoning, and productive disposition. We developed an instrument to identify students’ understanding of fractions with multiplication and division and conducted the survey in which 149 6th-graders participated. The findings from the data analysis suggested that overall, the 6th-graders seemed not to understand fractions conceptually; in particular, their understanding is limited to a particular model of part-whole fraction. The students showed a tendency to use memorized procedure-invert and multiply in a given problem without connecting the procedure to the concept of the division of fractions. The findings also proposed that on a given problem-solving task that suggested a pathway in order for the students to apply or follow the procedures in a new situation, they performed the computation very fluently when dividing two fractions by multiplying by a reciprocal. In doing so, however, they appeared to unable to connect the procedures with the concepts of fractions with division.

강의역량에 대한 교수자와 학습자 간 인식 차이 분석: 대학의 강의평가를 중심으로

박현재(Park, Hyunjae),김대중(Kim, Daejoong) 한국핵심역량교육학회 2021 핵심역량교육연구 Vol.6 No.2

본 연구는 대학에서 강의평가로 대표되어지는 교수자의 강의역량에 대해 교수자인 교수 집단과 학습자인 학생 집단을 동시에 분석하였다. 강의평가제도를 통한 강의의 질이 제대로 이루어지기 위해서는 교수자는 학습자에 대해, 학습자는 교수자의 입장이 어떠한지를 파악하는 것은 중요하다. 그러나 강의평가를 기반으로 한 제반적 강의역량에 대한 교수집단과 학생집단 간 인식 차이를 학술적으로 연구된 논문이 없다는 것이다. 본 연구 수행을 위해 국내 종합사립대이며 다양한 전공과 계열을 갖춘 중형 규모의 D대학을 조사대상으로 분석이 이루어졌다. 분석방법으로 t검정, 의견의 내용타당도 검정인 CVR, 그리고 요인 간 영향관계 분석을 위해 회귀분석이 사용되었다. 주요 결과로는 첫째 4개의 세부질문(강의평가 구성 적절성, 교수의 강의 개선 활용성, 교수의 강의평가 내용 인지, 학생의 강의평가 답변 객관성) 중 학생의 강의평가 답변을 제외하고는 교수 집단의 평균 인식 값이 높게 나타났다. 다음으로 강의역량을 측정하는 데 있어서 강의평가 항목의 중요성에 대한 교수 집단과 학생 집단 간 인식 차이를 살펴본 결과, 교수 집단이 학생 집단보다 강의역량 관련 강의평가 요인들을 더 중요하게 인식하는 것으로 분석되었다. 마지막으로 회귀분석을 통한 두 집단의 인식 차이의 유사성과 차이점을 비교해 본 결과, 먼저 영향력이 높은 1에서 3순위에 해당되는 독립변수(강의의 충실성 관련)는 동일하게 나타났다. 다음으로 교수 집단은 교수와 학생 간 상호작용이 관련 독립변수가, 그리고 학생 집단은 공정한 평가 관련 독립변인이 더 강의 만족도에 더 영향력이 있는 것으로 나타났다. 이처럼 교수 집단과 학생 집단 간 인식 차이는 분명히 존재함이 확인되고, 어느 영역과 요인인지 그러한지를 본 연구에서 분석되어졌다. 도출된 연구결과들은 향후 대학 당국 입장에서는 현실성 있는 강의평가제도를 개선하는 데 참고자료로 활용될 수 있으리라 본다. In this study, the professor group and the learner group were simultaneously analyzed for the instructor s teaching competency, which is represented by lecture evaluation in universities. For the quality of lectures through the lecture evaluation system to be properly implemented, it is important for the instructor to understand the position of the learner and the learner on the position of the instructor. However, there are no academic papers on the difference in perceptions between the faculty and student groups on overall teaching competency based on lecture evaluation. For the purpose of this study, analysis was conducted on a medium-sized university, which is a private general university in Korea and has various majors and departments. As analysis methods, the t-test, CVR, which is a test of content validity of opinions, and regression analysis were used to analyze the relationship between factors. As a result, the average of the professor group except for the student s answer to the lecture evaluation among the 4 detailed questions(appropriateness of lecture evaluation structure, the professor s use of lecture improvement, the professor s recognition of lecture evaluation content, and the objectivity of the student s lecture evaluation answer) was higher than that of the student group. Next, as a result of examining the difference in perceptions between the faculty and student groups on the importance of lecture evaluation items in measuring lecture competency, it was analyzed that the professor group perceived lecture ability-related lecture evaluation factors as more important than the student group. Finally, as a result of comparing the similarity and difference of perception difference between the two groups through regression analysis, the independent variable (related to lecture fidelity) with the highest influence 1 to 3 was found to be the same. And, in the faculty group the interaction between professors and students was an independent variable, and in the student group, the independent variable related to fair evaluation had more influence on lecture satisfaction. As such, it was confirmed that there was a clear difference in perception between the faculty group and the student group, and what areas and factors were analyzed in this study. It is expected that the derived research results can be used as reference materials for improving realistic lecture evaluation questions and systems from the perspective of university authorities in the future. Ultimately, from the point of view of the professor as the instructor, it can be used to develop the instructor s own teaching ability.

인터넷 개인방송 몰입과 시청자 참여의향에 대한 연구 : 몰입의 매개효과를 중심으로

박현재(HyunJae Park),이주영(Jooyoung Lee),이정훈(JungHoon Lee) 한국IT서비스학회 2020 한국IT서비스학회 학술대회 논문집 Vol.2020 No.1

인터넷 개인방송은 기존 미디어 채널과는 다르게 채팅이나, 댓글 등의 기능을 활용해 시청자와 활발하게 소통할 수 있다. 이에 따라 다양한 형태의 시청자 참여 콘텐츠가 생겨나고 있다. 하지만 인터넷 개인방송에서의 시청자 참여에 대한 연구는 부족한 실정이다. 따라서 본 연구에서는 인터넷 개인방송의 몰입에 영향을 미치는 요인들이 무엇인지 알아보고, 몰입 이 시청자 참여 의향에 영향을 미치는지를 알아보았다. 또한, 각 요인 들과 시청자 참여 의향 사이에 몰입이 매개효과를 가지는지 분석하였다. 마지막으로 인터넷 개인방송의 장르에 따라각 요인들을 인식하는 정도가 다른지 알아보았다. 인터넷 개인방송 몰입에 영향을 미치는 요인으로는 유희성, 정보성, 상호작용성, 동질감, 선호도 5개의 변수를 선정하였으며 연구를 위해 설문조사를 진행하였다. 분석 결과 인터넷 개인방송의 유희성, 상호작용성, 동질감, 선호도 등이 몰입에 영향을 미치는 것을 알 수 있었다. 몰입의 매개효과 분석은 5개 변수 모두 부분매개효과를 가지는 것을 증명하였다. 장르 별로 각 요인들을 인식하는 정도는 선호도를 제외하고는 차이가 없었다. 다만 장르별로 게임은 유희성과, 동질감, 선호도가 몰입에 영향을 미치며 뷰티 및 먹방 분야는 상호작용성, 동질감, 선호도가 몰입에 영향을 미치는 것을 증명하였다. 마지막으 로 일상 장르는 동질감 선호도가 유의미한 영향을 미치는 것을 알 수 있었다. 본 연구는 인터넷 개인방송에서의 시청자 참여에 대한 연구를 진행하였다는데 의미가 있으며 인터넷 개인방송을 진행하는 BJ 그리고 MCN의 방송기획자에게 시청자의 적극적인 참여를 위해 콘텐츠 장르 별로 중요하게 생각해야 하는 요인을 제시해 효과적인 콘텐츠 기획에 기여 할 수 있을 것으로 기대 한다.

Analysis of Research Trends in South Korean ODA for Ethiopia (2000-2015)

Kim HyunJae,Shon Mi,Kim YoungHwan,Park MinKyoung APEC국제교육협력원 2015 Asia-Pacific Cybereducation Journal Vol.11 No.2

The purpose of this study is to analyze the research trends in the South Korean Official Development Assistance (ODA), by examining the papers of degree thesis papers, project reports, and academic journals published from 2000 to 2015, as well as investigating and proposing the themes for future studies. According to the rubrics of analysis, from numerous papers, twelve thesis, twelve reports and eight academic journals were selected and considered following five analysis criteria; namely, published year, stakeholder of study, project procedure, methodology, and relevance to MDGs, the Millennium Development Goals. The results of the analysis are as follows: first, the papers associated with South Korean ODA for Ethiopia were published in 2008 for the first time. With steadily increasing numbers of thesis, reports, and journals, following after 2008, researches have conducted studies vigorously since 2011. However, investigations on the South Korean ODA for Ethiopia are noticeably insufficient, in comparison to the grant aids and concessional loans paid thus far. Secondly, the analysis appeared in twelve papers published by universities, eleven by government authorities, and eight by specialty magazines. Upon closer inspection, the government authority indicated Korea International Cooperation Agency (KOICA), and eight other specialty magazines, as well as the following: Korea Water Resources Association2), Korean Association of African Studies3), Korea Society of Agricultural Extension4), Korean Journal of Health Education and Promotion5), Journal of International Collaboration in Education6), Korea Research Society for Customs7),Perspectives in Nursing Science, The Women’s Studies8). Third, project procedure utilized as the criteria for the analysis. As a result, one feasibility study conducted in 2012 and 2013, one planning study in 2008 and 2010, two planning studies in 2013, one evaluation study in 2011 were identified. However, each project procedure paper for the 25 projects launched thus far were difficult to find. Papers for those have no relevance with ODA projects, and were considered as other studies. Fourth, papers relevant to the MDGs stand as such; 11 papers were linked with MDG 2, ‘Achieve universal primary education’. Three papers had relevance to MDG 1, ‘Eradicate extreme poverty and hunger’, one to MDG 3, ‘Promote gender equality’, three to MDG 5, ‘Improve maternal health’, four to MDG 6, ‘Combat HIV/AIDS malaria, and other diseases’, two to MDG 7, ‘Ensure environmental sustainability’, seven to MDG 8, ‘Develop a global partnership for development’. There were no papers connected with MDG 4, ‘Reduce child mortality’. Therefore, based on this trend analysis, broader spectrums and diverse methods of study should be implemented for the future studies with regard to the South Korean ODA for Ethiopia.

기업과 외부정보이용자 간 비대칭적 정보가 보수적 회계처리에 미치는 영향

박현재 ( Hyunjae Park ),배기수 ( Kheesu Bae ) 한국세무회계학회 2015 세무회계연구 Vol.0 No.45

기업의 경영자와 외부주주 사이에 존재하는 정보환경에 차이가 존재한다. 경영자는 더 많은 정보를 이용해 기회주의적인 행위를 하며, 외부주주는 정보환경의 차이를 줄이기 위해 경영자를 감시하기 위한 더 많은 대리인비용을 지불해야한다. Watts and Zimmerman(1986) 은 회계보수주의가 경영자의 기회주의적인 이익조정을 통제하는 역할을 한다고 주장하였으며, Watts(2003)는 회계보수주의가 경영자를 견제하고 감시하는 역할을 하기 때문에 대리인 비용을 감소시킨다고 주장하였다. 본 연구는 경영자와 외부주주 사이에 정보 불균형이 회계 보수주의를 강화시키는지 분석한다. 본 연구는 정보 불균형의 측정치로 관찰 가능한 회계이익과 과세소득의 차이(BTD)를 이용하며, Khan and Watts(2009)의 방법을 이용해 개별기업의 회계보수주의 정도를 측정한다. 2001년부터 2011년까지 유가증권상장기업 중 분석에 필요한 자료가 이용 가능한 4,202 기업-연도를 대상으로 분석한 결과, 첫째, 회계이익과 과세소득의 차이(BTD)가 회계보수주의 (C-SCORE)에 유의한 음(-)의 영향을 미치는 것이 확인되었다. 둘째, 회계이익과 과세소득의 차이에 절대값을 취한 값(ABTD)과 회계보수주의(C-SCORE)는 유의한 양(+)의 관련성이 확인되었다. 셋째, 추가분석으로 회계이익과 과세소득의 차이가 양(+)인 집단에서 회계이익과 과세소득의 차이(BTD)는 회계보수주의(C-SCORE)에 유의한 양(+)의 영향을 미쳤으며, 음(-)인 집단에서는 회계이익과 과세소득의 차이(BTD)가 회계보수주의(CSCORE) 에 유의한 음(-)의 영향을 미치는 것으로 나타났다. 종합적으로, 경영자와 외부주주 사이에 정보 불균형이 높을수록 회계보수주의가 강화되는 것으로 나타나 연구가설을 지지하였다. There are differences in the information environment should exist between corporate managers and external shareholders. Managers with more information act the opportunistic behavior and to pay more money for minority representatives will monitor the management in order to reduce the difference between the information environment. Watts and Zimmerman(1986) argue that accounting conservatism have been responsible for controlling the management of opportunistic earnings. Watts(2003) argue that reducing agency costs was due to the role of conservatism that checks and monitors the executive. The purpose of this study was to analyze how to strengthen the information asymmetry between managers and outside shareholders accounting conservatism. This paper used the difference(BTD) of the measurements to observable accounting profit and taxable income of the information asymmetry and conservatism of the individual company level measured using the method of Khan and Watts(2009). This paper empirically test this prediction using 5,485 firm-year. First, we find that differences between accounting income and taxable income(BTD) has a significant negative influence to conservatism(CSCORE). Second, we find that the absolute value of the difference between accounting income and taxable income(ABTD) has a significant positive influence to conservatism(CSCORE). Third, we find that in robust analysis difference between accounting income and taxable income(BTD) in firm of positive BTD has a significant positive influence to conservatism(C-SCORE) and in firm of negative BTD has significant negative influence to conservatism(C-SCORE). Overall, increase of the information asymmetry between managers and outside shareholders appear to be strengthening conservatism supported the research hypothesis.

COVID-19 Vaccination Alters NK Cell Dynamics and Transiently Reduces HBsAg Titers Among Patients With Chronic Hepatitis B

Shin Hyunjae,Lee Ha Seok,Noh Ji Yun,고준영,Kim So-Young,Park Jeayeon,Chung Sung Won,Hur Moon Haeng,Park Min Kyung,Lee Yun Bin,Kim Yoon Jun,Yoon Jung-Hwan,Ko Jae-Hoon,Peck Kyong Ran,Song Joon Young,Shin E 대한면역학회 2023 Immune Network Vol.23 No.5

Coronavirus disease 2019 (COVID-19) vaccination may non-specifically alter the host immune system. This study aimed to evaluate the effect of COVID-19 vaccination on hepatitis B surface Ag (HBsAg) titer and host immunity in chronic hepatitis B (CHB) patients. Consecutive 2,797 CHB patients who had serial HBsAg measurements during antiviral treatment were included in this study. Changes in the HBsAg levels after COVID-19 vaccination were analyzed. The dynamics of NK cells following COVID-19 vaccination were also examined using serial blood samples collected prospectively from 25 healthy volunteers. Vaccinated CHB patients (n=2,329) had significantly lower HBsAg levels 1–30 days post-vaccination compared to baseline (median, −21.4 IU/ml from baseline), but the levels reverted to baseline by 91–180 days (median, −3.8 IU/ml). The velocity of the HBsAg decline was transiently accelerated within 30 days after vaccination (median velocity: −0.06, −0.39, and −0.04 log10 IU/ml/year in pre-vaccination period, days 1–30, and days 31–90, respectively). In contrast, unvaccinated patients (n=468) had no change in HBsAg levels. Flow cytometric analysis showed that the frequency of NK cells expressing NKG2A, an NK inhibitory receptor, significantly decreased within 7 days after the first dose of COVID-19 vaccine (median, −13.1% from baseline; p<0.001). The decrease in the frequency of NKG2A+ NK cells was observed in the CD56dimCD16+ NK cell population regardless of type of COVID-19 vaccine. COVID-19 vaccination leads to a rapid, transient decline in HBsAg titer and a decrease in the frequency of NKG2A+ NK cells.