JPEG2000 CODEC을 위한 Entropy 코딩 알고리즘의 VLSI 설계

이경민,오경호,정일환,김영민,Lee, Kyoung-Min,Oh, Kyoung-Ho,Jung, Il-Hwan,Kim, Young-Min 한국통신학회 2004 韓國通信學會論文誌 Vol.29 No.1C

본 논문은 차세대 정지영상 압축방식인 JPEG2000 코덱의 엔트로피 코딩 알고리즘의 하드웨어적 구조를 제안하고, 설계하였다. 구현된 엔트로피 코더는 컨텍스트 기반의 산술부호화기로서 컨텍스트 추출부(CE)와 산술부호화기(AC)로 구성된다. CE는 각 코팅패스에서 코딩에 참여하지 않는 샘플은 skipping 함으로써 동작속도를 향상시켰으며, AC는 MQ coder에 기반을 둔 산술부호화기로서, 곱셈과 나눗셈 연산대신 단순 가감산과 shift 연산망을 이용하여 구조를 단순화하고 연산량을 줄임으로써 동작속도를 향상시켰다. 설계된 엔트로피 코더는 VHDL 모델링후 Xilinx FPGA technology를 이용하여 합성한 후 동작을 검증하였으며, 30MHz의 동작속도를 보인다. In this paper, we design an efficient VLSI architecture of entropy coding algorithm in JPEG2000. Entropy coder is a context-based binary arithmetic encoder, and composed of a Context Extractor(CE) and an Arithmetic Coder(AC). We speed-up CE by skipping no-operation bits in coding passes, and AC is to be performed based on MQ coder. Because of using Qe value associated with each allowed context and probability estimation, MQ coder is a multiplication free coder that reduces computation loads and makes simple the structure of arithmetic coder. We have developed and synthesized the VHDL models of CE and AC pairs using Xilinx FPGA technology. The proposed architecture operates up to 30MHz.

메쉬 직물의 밀도 및 위치변화에 따른 흡음특성

이경민,전두환,전상후,Lee, Kyoung Min,Chun, Du Hwan,Chun, Sang Hoo 한국섬유공학회 2015 한국섬유공학회지 Vol.52 No.3

Sound absorbing materials are generally categorized as porous-type absorbers and panel-type absorbers. In addition, their absorbing mechanism is typically described as a conversion of sound energy into heat energy through the dynamic behavior of the material. Thus one of the important parameters influencing the sound absorption characteristics is the density of the material. This study investigated the sound absorption characteristics of a mesh fabric based on the mesh density and fabric layering structure. Four different mesh densities (130, 180, 200, and 230 T) combined with five different layering structures were investigated to help understand the mechanism and effect of the sound absorption characteristics. The results indicate that a panel-type absorber has better sound absorption characteristics within a lower frequency range, whereas a porous-type absorber performs better at a higher frequency. In addition, the increased fabric density of the mesh fabric shows a better performance in terms of sound absorption. An empirical equation between the sound absorption coefficient and the fabric density was also derived for further design applications.

눈꺼풀 종괴로 나타난 소아황색육아종 1예

이경민,김남주,Kyoung Min Lee,Nam Ju Kim 대한안과학회 2008 대한안과학회지 Vol.49 No.7

Purpose: To report one case of juvenile xanthogranuloma presenting as a unilateral nodule of the eyelid. Case summary: A 4-year-old girl presented with a solitary eyelid nodule. There were no other ophthalmologic problems. Excisional biopsy and simple wound closure were performed. A biopsy showed intense infiltration of histiocytes, lymphocytes, and multinucleated giant cells in the dermis, which was compatible with juvenile xanthograunuloma. Conclusion: Juvenile xanthogranuloma should be considered in the differential diagnosis of a solitary eyelid tumor. J Korean Ophthalmol Soc 49(7):1173-1176, 2008

Methyl fluoroperoxide와 fuoromethyl fluoroperoxides의 conformers와 isomers 구조에 대한 이론연구

이경민,성은모,Lee, Kyoung-Min,Sung, Eun-Mo 대한화학회 2011 대한화학회지 Vol.55 No.3

Methyl hydro-peroxide의 methyl group과 O-H에 F를 치환 시킨 fluoromethyl fluoroperoxide($CH_nF_{3-n}OOF$)의 안정한 conformers와 isomers에 대하여 MP2/6-311G(d,p) 방법과 B3LYP/6-311++G(d,p) 방법으로 최적화 계산을 수행하였고 vibrational frequencies를 구하였다. $CH_3OOF$와 $CH_2FOOF$, $CHF_2OOF$, $CF_3OOF$ 분자 모두 가장 안정한 형태는 skew 구조로 나타났으며 $CH_3OOH$와 비교할 때 대단히 짧은 O-O 결합길이를 갖는다. Trans, cis conformers의 경우 skew 형태보다 8-12 kcal/mol 정도 높은 에너지를 갖으며 O-O 결합길이는 훨씬 길어진다. $CH_2FOOF$, $CHF_2OOF$, $CF_3OOF$ 분자들은 methyl group의 F에 의한 induction 효과로 짧은 C-O 결합길이를 갖고 O-F 결합길이는 길어지나 치환된 F 원자의 수에 따른 구조변화는 그리 크지 않다. The ab initio calculations for fluoromethyl fluoroperoxides have been carried out using MP2/6-311G(d,p) and B3LYP/6-311++G(d,p) method. The structural optimizations were performed for several isomers and conformers of methyl fluoroperoxide, $CH_3OOF$ and the vibrational frequencies were calculated. The most stable conformer of $CH_3OOF$ is skew form and has fairly short O-O bond distance. The trans and cis conformers have 8-12 kcal/mol higher energies than skew form and the other isomers are very unstable. The structures of $CH_2FOOF$, $CHF_2OOF$ and $CF_3OOF$ are also optimized and vibrational frequencies were calculated. These molecules also have skew forms as the lowest energy conformers. The O-O bond distances are longer and C-O bond distances are shorter than $CH_3OOF$, but the structural parameters are almost independent of the number of fluorine atoms in methyl group.

옻에 대한 문헌적 고찰

이경민,권기록,최성모,김태희,Lee, Kyoung-Min,Kwon, Ki-Rok,Choi, Sung-Mo,Kim, Tae-Hee 대한약침학회 2002 Journal of pharmacopuncture Vol.5 No.1

Objective: It will be examined in this research whether Lacquer poison can be used as an distinguished treatment to cure incurable diseases by considering literature existing and various papers. Method: I studies origin, alias, species, toxicity, effect, treatment, component, medical action and contraindication of Rhus vemiciflua stokes through various kinds literatures. Results: Sap of Rhus vemiciflua stokes that is used for medical purposes, has an effect on anti-tumor, anti-oxidation, hangover cure, and gastritis suppression. Even though urushiol and fIavonoids, the main ingredient of lacquer, has medical cure effects. but urushiol results in a dermatropic allergy. Sincc xylem of a Rhus vemiciflua stokes, however. does not induce the allergy but has medical efficacy, research on this topic is needed.

각막굴절교정수술 이후 안압 상승의 위험인자

이경민,김미금,위원량,이진학,Kyoung Min Lee,Mee Kum Kim,Won Ryang Wee,Jin Hak Lee 대한안과학회 2010 대한안과학회지 Vol.51 No.10

Purpose: To investigate changes in intraocular pressure (IOP) after corneal refractive surgery and determine risk factors associated with increased IOP (IIOP). Methods: This retrospective observational study was comprised of 450 eyes of 225 patients, each of whom had corneal refractive surgery in Seoul National University Hospital between January 2004 and January 2008, and were followed for more than one month. IIOP was defined as IOP above 130% of the predicted IOP, adjusted according to corneal thickness and repeated more than twice after postoperative 1 week or after anti-glaucoma medication was needed. Correlation and stratified regression analyses were performed for eyes with myopia and IIOP. Logistic regression analysis was performed to assess risk factors of IIOP and need for medication. Results: IIOP was detected in 22.2%, and anti-glaucoma medication was required in 12.0%, of eyes. The mean IIOP of the medication group was 5.6 ± 3.4 mmHg. Stratified regression analysis showed that the proportion of IIOP did not differ significantly by the degree of myopia. Logistic regression analysis revealed that statistically significant risk factors of IIOP were female gender, preoperative low IOP, and thicker cornea. The statistically significant risk factor of need for medication was the corneal thickness. Conclusions: Thick corneal thickness was found to be a significant risk factor of IIOP after corneal refractive surgery was performed, and IIOP was not affected by the degree of myopia. J Korean Ophthalmol Soc 2010;51(10):1333-1337

통찰 발생과정에 있어 막다른 골목과 재구조화의 기능에 대한 고찰

이경민(Lee Kyoung Min) 한국창의력교육학회 2016 창의력교육연구 Vol.16 No.3

본 연구는 통찰이 발생하는 과정에 대한 최근의 연구들이 주로 다루고 있는 막다른 골목과 재구조화의 발현기제를 이론적으로 검토함으로써, 창의적인 문제해결 과정에 대한 보다 정밀한 이해를 도모하기 위해 수행되었다. 막다른 골목과 재구조화라는 개념은 일화적이고 일상적인 의미로 다소 느슨하게 사용되었던 통찰의 발생과정에 대한 논의를 과학적이고 실증적으로 검증할 수 있게 하였다. 하지만 이 개념을 기초로 수행된 연구들이 통찰의 발현과정에 대한 논란을 증가시키고 있는 것 또한 무시할 수 없는 사실이다. 본 논문은 이러한 문제를 해결하기 위한 하나의 방안으로 막다른 골목과 재구조화라는 개념에 근거하여 제안된 통찰의 발현기제를 분석하고 내재된 문제점을 검토하였다. 본 연구는 통찰의 발생 과정에 관한 논쟁의 원인을 이론적으로 규명하고 향후 연구의 방향성을 제시한다는 점에서 의의가 있다 할 것이다. This research was conducted for examining the function of impasse and restructuring. Even thought it is true that the two concepts have been proposed by Gestalt psychologist, it is not fully examined the validity of these two concepts. The results of the current examination told that these two concepts has two theoretical problems in terms of falsifiability and testability. These findings would be helpful to understand the reason why contradictory findings has been reported from insight related research and help the researchers develop more sophisticated programs regarding enhancing creative problem solving ability.

혈액 - 뇌관문에서의 유기음이온 수송계와 efflux inhibitor 의 영향

이경민(Kyoung Min Lee),강영숙(Young Sook Kang) 한국약제학회 1999 한국약제학회 총회 및 학술대회 요지집 Vol.- No.29

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통찰에 대한 실험연구는 통찰의 발생 과정을 반영하는가?

이경민(Lee Kyoung min),임웅(Lim Woong) 한국창의력교육학회 2014 창의력교육연구 Vol.14 No.2

통찰은 창의적인 산물이 만들어지는 과정에 결정적인 역할을 한다고 알려져 왔다. 하지만 통찰을 만드는 재료가 무엇인지에 대해서는 아직 완전한 합의가 이루어지지 못한 실정이다. 본 논문은 통찰의 과정을 밝히려는 실험연구에서 지속적으로 보고되는 상반된 연구결과의 원인을 분석하여, 이를 바탕으로 실험에 사용되는 실험문제와 실험절차에 대한 문제점을 지적한다. 또한 이러한 문제점을 해결하고 보다 타당한 연구결과를 도출할 수 있는 방법론적 설계에 대해 논의하고 있다. 본 논문에서 제안하는 방법론적 대안은 통찰의 발현기제와 관련 변인의 역할을 이해하는데 도움을 줄 수 있을 것이다. It has been proposed that an insight is crucial to make creative product. However, there is no consensus yet what makes it and its process is. Moreover experimental research focused in this topic has reported controversial results. This study examined what makes this controversial results. The authors argued that these controversial ones were caused by using pure-insight problems and by one-step experimental procedure. This study proposed that it would be considered using hybrid-insight problems involved both perceptual functions and domain-related knowledge or strategy. In addition, two-step procedures would be better to confirm the difference between experimental and control group. These two proposals on this study may let the controversial results reconcile with.

신품종 포도의 송이 부위별 생리적 특성

이경민(Kyoung Min Lee),최윤수(Yun Soo Choi),임병선(Byung Seon Lim),김진국(Jin Gook Kim),황용수(Yong Soo Hwang) 한국원예학회 2010 한국원예학회 학술발표요지 Vol.2010 No.10