Blood Oxygen Level Sensor를 이용한 대뇌혈류증가 장치

임정현,조인희,김영길,Lim, Jung-hyun,Joh, In-Hee,Kim, Young-kil 한국정보통신학회 2018 한국정보통신학회논문지 Vol.22 No.8

대뇌혈류를 증가 시키는 수술은 뇌경색의 치료방법중 하나이다. 이러한 침습적인 방법을 보완하기 위해 사람의 혈압을 이용해, 사지에 압박을 가하여 대뇌 혈류를 증가 시키는 비 침습적인 장치도 등장하였다. 그러나 속도와 정확성이 떨어지는 문제점이 제기되었다. 본 논문에서는, 정확한 측정과 측정하는 데에 걸리는 시간을 기존의 장치보다 개선하기 위해, Blood Oxygen Level Sensor를 이용하여, 양팔에 압력을 주면서 각 팔의 Perfusion Index를 측정하여, Perfusion Index가 일정 값 이하로 떨어지는 순간의 75% 압력을 팔에 가하고, 다리에는 팔에서 구해진 압력 값을 이용해 계산하여 얻은 압력을 가한다. 기존의 혈압 측정식 대뇌혈류증가 장치와 같이, 혈류량을 20%이상 증가 시킬 수 있고, 또한 측정 시간도 단축한 결과를 얻어 뇌경색 환자에게 선택적으로 사용할 수 있다. Surgery to increase cerebral blood flow is one of the treatment methods of cerebral infarction. In order to supplement this invasive method, non-invasive devices have been introduced that use human blood pressure to pressurize the extremities to increase cerebral blood flow. However, the problem of poor speed and accuracy was raised. In this paper, the perfusion index of each arm is measured by applying pressure to both arms using Blood Oxygen Level Sensor to improve the accuracy of measurement and measurement time. The pressure applied to the arm is calculated by using the pressure value obtained from the arm. Like the existing blood pressure measuring cerebral blood flow increasing device, the blood flow can be increased by more than 20% and the measurement time can be shortened, so that it can be selectively used for the patient with cerebral infarction.

한국인 영어 학습자의 오도 문장에 대한 이해와 읽기 과제의 영향

임정현(Lim, Jung Hyun) 한국언어학회 2021 언어 Vol.46 No.2

The purpose of the present study is to examine how L2 learners interpret locally ambiguous ‘garden-path’ sentences, and whether and in what way different reading tasks affect the comprehension of such garden-path sentences. Using an offline experiment, participants were given two types of reading conditions. In one condition, they were asked to read sentences and answer comprehension questions, while in the other , they were told that they might have to perform grammatical judgments on some of the sentences at random, before then answering comprehension questions. The rationale of differentiating between the tasks was to manipulate reading goals . Results showed that participants responded incorrectly more often to the garden-path sentences than when not in the garden-path conditions . This indicated that L2 learners were quite likely to arrive at a final interpretation while lacking full syntactic analysis when reading garden-path sentences, which is consistent with previous studies. More importantly, reading tasks yielded different patterns of sentence comprehension. Specifically, the accuracy of comprehension was higher when the reading goal was to randomly make grammatical judgments on parts of the sentence than when the goal was solely to answer comprehension questions. Results were discussed in terms of ‘good-enough (GE)’ representations in L2 language comprehension.

편심하중이 작용하는 수평 곡선 I 형 거더의 휨·비틀림 상호작용

임정현(Lim, Jung-Hyun),이기세(Lee, Kee-Sei),김희수(Kim, Hee-Soo),최준호(Choi, Jun-Ho),강영종(Kang, Young Jong) 한국산학기술학회 2015 한국산학기술학회논문지 Vol.16 No.9

수평 곡선 I-형 거더에는 초기곡률이라는 기하학적 특성으로 인해 휨 모멘트와 더불어 비틀림 모멘트가 작용하게 된다. 이러한 휨·비틀림 거동은 서로 상호 작용을 일으켜 약축방향으로 2차 휨거동을 유발하게 된다. 휨과 비틀림 간의 상호 작용은 곡선 거더를 조기에 비선형 상태 및 소성 상태로 유도하여 내하력의 저하를 야기하게 되고, 차량의 이동 위치에 따른 편심 하중은 비틀림을 더욱 증대시킬 수 있다. 그러나 기존에 연구되어왔던 직선 거더에 대한 휨·비틀림 상호관계식은 곡선 거더가 가지고 있는 거동 특성이 고려되지 않았기 때문에 수직하중을 받는 수평 곡선 I-형 거더의 극한 강도가 과대평가 될 수 있다. 따라서 이에 대한 보다 명확하고 합리적인 제안식의 적용이 곡선 거더의 설계 시에 필요하다. 본 연구에서는 유한요소해석을 통하여 편심하중이 작용하는 수평 곡선 I형 거더의 휨·비틀림 상호작용 특성을 파악하고 거동분석을 수행하였다. With bending moment, torsional moment due to geometric properties as “Initial curvature” acts in horizontally curved I-girder. These behavior causes the secondary effect of bending in minor-axis because of interaction between bending and torsion. The bending and torsion interaction cause a loss of load bearing capacity by induced the early inelastic or plasticity condition in curved girder. Also eccentric load by movements of traffic can increase torsion. However, Equation of interaction between bending and torsion for straight girder, not deal with characteristics of curved girder behavior in previous studies, can be overestimated for ultimate strength in horizontally curved I-girder acting vertical force. Therefore, using more rational, obvious suggestion is required when design curved girder. In this study, we identified the bending-torsional moment interaction for the horizontally curved I-girder of the eccentric load acting by FEM analysis.

국화 ‘수방력’의 Multiple-Somatic Embryo의 유기 및 발달에 대한 형태학적 관찰

임정현(Jung-Hyun Lim),손기철(Ki-Cheol Son),오승은(Seung-Eun Oh) 한국원예학회 2005 원예과학기술지 Vol.23 No.2

형질전환에 의한 국화의 품질 개선은 효과적인 재분화 체계에 의해서 결정된다. 따라서 본 연구에서는 절편체로서 가장 적합한 multiple-somatic embryos(M-SE)의 재분화력을 다른 종류의 절편체와 비교하고 잎 절편체를 중심으로 1차 체세포배 발생을 형태학적으로 관찰하였다. 잎 절편체의 경우 표피와 표피 아래에 위치한 세포층에서 세포분열이 일어나며 대부분의 세포들은 액포가 커지면서 부피만 증가하지만, 몇몇 세포들은 분열 후에도 작은 상태로 유지되면서 전배(proembryo)를 형성하였다. 그 후 구형 단계의 체세포배가 잎 표면으로부터 유도되었고 동시에 기관형성에 의한 배도 관찰되었다. 특히 자엽형의 체세포배의 경우 정단분열조직을 가지고 있어 자엽형 체세포배가 형성되기 전에 아그로박테리움을 접종하면 변이와 키메라를 줄일 수 있을 것으로 판단된다. 잎이나 꽃잎 절편체보다 재분화율이 높은 M-SE 절편체의 경우 재분화 배지에 옮긴지 10일 후면 전배가 형성되었다. 따라서 M-SE 절편체는 식물의 재분화 체계에 효율적으로 이용할 수 있다. Successful application of plant transformation to improve the quality of chrysanthemum will mainly depend on the availability of an efficient regeneration system. In this study, therefore, the capability of regeneration of multiple-somatic embryos (M-SE), the most appropriate as regeneration primordia or explants, was compared to that of other types of explants, and the progress of the 1st somatic embryogenesis from the leaf explant was observed by histological analysis. In leaf tissue, cell divisions in the epidermal layer and subepidermal layers occurred repeatedly and most of these cells became bulky with large vacuoles, but some of them remained small after division and then formed a proembryo. Soon after, the globular stages in somatic embryos were protruded from leaf surface, indicating that the origin of somatic embryo stemmed from the leaf surface. However, there were some embryos formed by organogenesis. Because the cotyledonary stage of somatic embryos contained meristematic tissue, variation or chimera in transgenic somatic embryos could be reduced when agrobacterium was inoculated in the embryos before cotyledonary stage. Finally, the explant of M-SE which showed a high level of regeneration rate compared to leaf and petal explants, formed new proembryos in 10 days after transferred to regeneration medium. Therefore, it was found that M-SE could be very effectively applied as an explant in the construction of plant's regeneration system.

무선통신 프로토콜의 충돌방지 알고리즘 개선

임정현(Lim Jung-Hyun),이권익(Lee Kwoun-Ig),양두영(Yang Doo-Yeong),김흥수(Kim Heung-Soo),고재권(Ko Jae-Kweon) 한국방송·미디어공학회 2007 한국방송공학회 학술발표대회 논문집 Vol.2007 No.-

본 논문은 유비쿼터스 센서 네트워크와 텔레매틱스 서비스에 사용되는 무선 환경 프로토콜 표준 중 UHF 대역 프로토콜인 EPCglobal의 Class 1 Gen 1, Class 1 Gen 2의 에어인터페이스를 분석하고 각 프로토콜에서 규정된 충돌방지 알고리즘을 구현하였다. 그리고 각 프로토콜에서 규정하는 충돌방지 알고리즘의 성능을 개선한 알고리즘을 제안하고 성능을 비교하였다. 개선된 알고리즘과 표준 알고리즘의 성능 시뮬레이션 결과 개선된 Class 1 Gen 1 알고리즘은 태그 수 100개 일 때 54.5%, 태그 수 1000개 일 때 63.4% 감소하였다. 개선된 Class 1 Gen 2 알고리즘은 태그 수 100개 일 때 7.9%, 태그 수 1000개 일 때 11.7% 감소하였다. 개선된 충돌방지 알고리즘은 표준 알고리즘보다 태그 인식 성능이 상당히 개선됨을 알 수 있다. 따라서 개선된 충돌방지 알고리즘은 유비쿼터스 센서 네트워크와 텔레매틱스 서비스 등에 사용되는 무선인식 시스템의 성능 개선 방안으로 적용될 수 있다.

엽채류 기계정식 시 고온기 웃자람방지를 위한 비가림하우스 내 LED 처리가 배추 등 엽채류 묘 생육에 미치는 영향

임정현(Jung-Hyun Lim),장석우(Suk-Woo Jang),박수형(Su-Hyoung Park),최승국(Seoung-Kook Choi),김성겸(Sung-Kyeom Kim),이민지(Min-Ji Lee),박경빈(Gyeong-Bin Park) 한국원예학회 2017 한국원예학회 학술발표요지 Vol.2017 No.10

한국 동해 생태계의 어획강도 변화에 따른 자원량 예측 연구

임정현 ( Jung-hyun Lim ),서영일 ( Young-il Seo ),장창익 ( Chang-ik Zhang ) 한국수산해양기술학회(구 한국어업기술학회) 2018 수산해양기술연구 Vol.54 No.3

Overfishing capacity has become a global issue due to over-exploitation of fisheries resources, which result from excessive fishing intensity since the 1980s. In the case of Korea, the fishing effort has been quantified and used as an quantified index of fishing intensity. Fisheries resources of coastal fisheries in the Korean waters of the East Sea tend to decrease productivity due to deterioration in the quality of ecosystem, which result from the excessive overfishing activities according to the development of fishing gear and engine performance of vessels. In order to manage sustainable and reasonable fisheries resources, it is important to understand the fluctuation of biomass and predict the future biomass. Therefore, in this study, we forecasted biomass in the Korean waters of the East Sea for the next two decades (2017~2036) according to the changes in fishing intensity using four fishing effort scenarios; fcurrent, fpy , 0.5×fcurrent and 1.5×fcurrent . For forecasting biomass in the Korean waters of the East Sea, parameters such as exploitable carrying capacity (ECC), intrinsic rate of natural increase (r) and catchability (q) estimated by maximum entropy (ME) model was utilized and logistic function was used. In addition, coefficient of variation (CV) by the Jackknife re-sampling method was used for estimation of coefficient of variation about exploitable carrying capacity (CVECC). As a result, future biomass can be fluctuated below the BPY level when the current level of fishing effort in 2016 maintains. The results of this study are expected to be utilized as useful data to suggest direction of establishment of fisheries resources management plan for sustainable use of fisheries resources in the future.

임상 연구 : 혈액투석 환자에서 Tunneled Cuffed Central Venous Catheter와 동정맥루간의 투석량과 투석효율의 차이

임정현 ( Jung Hyun Lim ),최승원 ( Seung Won Choi ),안종준 ( Jong Joon Ahn ),박종하 ( Jong Ha Park ),정현철 ( Hyun Chul Chung ),신상훈 ( Sang Hun Shin ),이지호 ( Ji Ho Lee ),이종수 ( Jong Su Lee ) 대한신장학회 2006 Kidney Research and Clinical Practice Vol.25 No.4

Cognate Facilitation Effects in Cross-Script Languages: Evidence from Unbalanced Korean-English Bilinguals

Jung Hyun Lim(임정현),Mao Cui,Hee-Don Ahn(안희돈) 한국언어학회 2020 언어 Vol.45 No.1

The purpose of this paper is to examine the questions of how the amount of phonological information manipulates the cognate facilitation effect and to what extent the L2 proficiency modulates the priming effect. A lexical decision task in L2 to L1 direction was performed with Korean-English unbalanced bilinguals, whose languages have no overlaps in orthography. The experiment yielded the results that the participants were influenced by short or long pronounced words (i.e., the amount of phonological information) and that there was a cognate facilitation effect even with different-script languages in backward translation direction. The results also reported a role of L2 proficiency on the priming effect. These results are discussed within several models of lexical bilingual organization.

CVM을 이용한 대중교통서비스 개선에 따른 경제적 가치 분석

임정현(Jung Hyun Lim),고태호(Tae Ho Ko),황경수(Kyung Soo Hwang),양영철(Young Chul Yang) 서울행정학회 2007 한국사회와 행정연구 Vol.18 No.1

The cost-benefit analyses of public policies have been dealt carelessly in the past due to the difficulty in being able to illustrate the public benefits in monetary value. For an efficient reformative policy for the public transportation to be implemented, the benefits and costs resulting from the policy implementation must first be analyzed. The efficient supply of public goods can be achieved when the marginal cost of public transportation service equals the marginal benefit of the individuals. But the benefits following the reformation of public transportation is a non-market good, which makes its valuation difficult. To solve this problem, this research applies the contingent valuation method (CVM) that measures the value of non-market goods in an attempt to measure the value of the reformation of public transportation service in Jeju region.