SIP를 이용한 멀티 유저 컨퍼런스 서버 설계와 구현

安弘榮,朴昡旭 弘益大學校 産業技術硏究所 2005 産業技術 Vol.15 No.-

SIP(Session Initiation Protocol) is Application-layer control protocol for creating, modifying and terminating multimedia sessions or calls with one or more participants. SIP is an IETF standards track protocol specified in RFC 3261. Recently many Application services using SIP are researched. In this paper, we present Multi-user Conference Server Design and Implementation based on SIP. We show multi-party Conference server model, explain extended SIP methods for conferencing and their scenario.

호스트기반 라우팅을 이용한 마이크로 이동성 관리

朴昡旭,安弘榮 弘益大學校 科學技術大學 大學院, 2004 産業技術 Vol.14 No.-

Mobile IP provides convenient and extensible global mobility management protocol. However It does not support fast Handoff and Paging. Local mobility management protocols like Cellular IP, HAWAI and Hierarchical Mobile IP are proposed to support frequent Handoff in intra IP domain. In this paper, we propose a new host-based routing algorithm which maximizes the advantage of extra links using controlled flooding. Simulation results show that a new routing algorithm has a better performance in packet loss and throughput metric.

클럽 샤프트(Club Shaft) 특성에 따른 골프 스윙(Golf Swing)동작 분석

김성일,김기형,김형수,이현섭,김진욱,안찬규,김희진 한국운동역학회 2002 한국운동역학회지 Vol.12 No.2

본 연구는 클럽 샤프트의 대표적인 재질인 그라파이트(graphite)의 유연한(flexible) 클럽 샤프트(club shaft)의 특성에 따라 피험자가 운동학적(kinematics) 요인이 되는 관절의 각변위, 각속도, 각가속도, 클럽헤드의 속도와 가속도와 같은 변인들이 어떻게 적응하는지 비교 분석하여 보다 효율적인 드라이버 선택에 도움을 주며 샤프트 특성에 따른 신체관절의 움직임에 대한 자료를 제시하고자 하였다. 고속 카메라 2대의 속도는 500fps로 하였고 각 regylar,stiff, x-stiff, 자신의 클럽을 포함 각 4개의 클럽을 사용하여 각 클럽당 3번씩 촬영하였으며 목표방향에서 20m이상 벗어나는 경우의 촬영은 다시 촬영하였다. 본 연구에서는 디지타이징(digitizing)을 신체 9개 마커는 강체로 가정된 클럽과 신체분절 모델로 정의하였으며 2 대의 카메라(500fps)로부터 얻은 avi화일을 컴퓨터에 저장하고 자료로부터 Butterworth 6th order recursive digital filter를 사용하여 1차 자료를 smoothing 하고 DLT를 이용하여 3차원 좌표를 구성하도록 한다. 좌표값을 얻기 위하여 kwon3d v3.0을 이용하였다. 본 실험은 피험자 스스로 클럽의 특성에 따라 스윙의 속도를 달리 하기 때문에 스윙의 시간이 달라지며 어느 정도 클럽이 강성에 따라 스윙시간이 빨라지는 결과로 나타났다. 이것은 피험자가 샤프트가 강성(stiffness)에 따라 스윙 속도를 빨리 하게 되는 원인이 되는 것으로 생각된다. 어깨의 각변위는 클럽이 regular의 경우 임팩트에서 각속도를 계속 유지하고 있으며 stiff, x-stiff의 경우에는 어깨의 움직임이 임팩트에서 급격하게 감소되는 것을 알 수 있다. 이것은 팔의 동작과 클럽의 힘을 크게 하기 위한 동작으로 생각된다. 어깨 각속도는 클럽이 stiff할수록 각속도가 큰 감속하는 것으로 나타났다. 손목속도는 regular 클럽의 경우 손목의 감속이 늦게 되고 임팩트에서 손목의 감속이 적게 하는 것으로 나타났으며 stiff와 x-stiff의 클럽에서 임팩트 시에 순간적인 감가속으로 인해 클럽의 속도를 증가시키고 있다. 임팩트 시에 손목의 감가속은 클럽헤드의 임팩트 시 속도를 증가시키는 결과를 보였다. 클럽헤드는 regular 클럽이 임팩트전에는 속도 증가가 커지는 결과와 일치된 결과를 보이고 있다. The purpose of this study was to find the rational method to analyze golf swing with specific property of club shaft. Three subjects were filmed by two high speed digital cameras with 500fps. The phase analyzed was downswing of each subject. The three-dimensional coordinates of the anatomical landmarks were obtained with motion analysis system Kwon3d 3.0 version and smoothed by lowpass digital filter with cutoff frequency 6Hz. From these data, kinematic and kinetic variables were calculated using Matlab(ver 5.0) The variables for this study were angular velocity and accelerations, which were calculated and following conclusions have been made : 1) Golf swing time of stiff club is faster than that of regular club. 2) In shoulder joint motion of swing with the stiff club, x-stiff showed mort rapid negative acceleration than that of regular club. 3) In regular club, the velocity of club head would be more effective velocity, which was increasing, than those of other clubs before impact. 4) In wrist joint motion of swing with stiff club, x-stiff club showed faster than regular club in the downswing and impact more rapid negative acceleration.

젊은 여성과 중년 여성의 과민성방광증후군과 요실금의 유병율

김욱현(Uk Hyun Kim),김준모(Jun Mo Kim),김영호(Young Ho Kim),전윤수(Yoon Soo Jeon),김민의(Min Eui Kim),이남규(Nam Kyu Lee),박영호(Young Ho Park),안현철(Hyun Chul Ahn),김증임(Jeung Im Kim),서주태(Ju Tae Seo) 대한여성건강학회 2003 여성건강 Vol.4 No.1

LPS로 유도된 RAW 264.7 세포와 마우스 귀조직에 대한 참모자반 (Sargassum fulvellum) 에탄올 추출물의 항염증 효과

정다현(Da-Hyun Jeong),김꽃봉우리(Koth-Bong-Woo-Ri Kim),김민지(Min-Ji Kim),강보경(Bo-Kyeong Kang),박시우(Si-Woo Bark),박원민(Won-Min Pak),김보람(Bo-Ram Kim),안나경(Na-Kyung Ahn),최연욱(Yeon-Uk Choi),안동현(Dong-Hyun Ahn) 한국식품영양과학회 2014 한국식품영양과학회지 Vol.43 No.8

본 연구에서는 천연식물자원인 참모자반 에탄올 추출물 (SFEE)의 항염증 활성을 알아보기 위하여 in vitro 및 in vivo 실험을 진행하였다. 먼저 SFEE의 세포독성을 살펴보기 위하여 RAW 264.7 대식세포를 이용하여 세포 생존율을 살펴본 결과, SFEE 100 μg/mL의 농도까지 전혀 독성을 나타내지 않았다. 또한 항염증 효과를 알아보기 위하여 in vitro type으로 LPS로 염증을 유도한 RAW 264.7 세포에 대하여 NO, IL-6, TNF-α 및 IL-1β 분비량과 iNOS, COX-2 및 NF-κB와 같은 염증성 단백질의 발현량을 측정하였다. 대식세포 배양액의 NO₂- 농도를 측정한 결과 SFEE 첨가 농도에 따라 유의적으로 분비량이 감소하는 것을 확인하였으며, 100 μg/mL의 농도에서 90% 이상 억제됨을 확인하였다. 또한 100 μg/mL의 농도로 첨가 시 염증성 사이토카인인 IL-6, TNF-α 및 IL-1β 분비량을 각각 79, 73, 87%억제함을 확인하였으며, NO 생성과 연관이 있는 iNOS 단백질과 COX-2 및 NF-κB 단백질의 발현이 현저히 억제됨을 확인하였다. 이러한 SFEE의 항염증 효과를 동물모델에서 확인하기 위해 in vivo 실험을 진행한 결과 croton oil로 유도한 마우스 귀 부종을 유의적으로 억제함을 확인하였고, 조직검사 결과 염증 반응에 의한 경피 및 진피 두께의 발달을 현저히 억제시키고 염증성 세포인 비만세포의 조직으로의 침윤을 억제하여 항염증 효과를 가짐을 입증하였다. 결론적으로 참모자반 에탄올 추출물은 염증 반응의 전사인자인 NF-κB의 발현을 억제하여 iNOS와 COX-2의 발현을 억제시키고 그에 의해 NO, IL-6, TNF-α 및 IL-1β 분비를 억제하여 항염증 활성을 가지는 것을 확인하였으며, 따라서 참모자반 에탄올 추출물이 염증성 질환의 예방 및 개선에 유용할 것으로 사료된다. This study investigated the anti-inflammatory effects of Sargassum fulvellum ethanol extract (SFEE) on the lipopolysaccharide (LPS)-induced inflammatory response. SFEE remarkably suppressed production of NO and pro-inflammatory cytokines (IL-6, TNF-α, and IL-1β) at 50 and 100 μg/mL. There were no cytotoxic effects on proliferation of macrophages treated with SFEE compared to the control. SFEE reduced expression of iNOS and COX-2 proteins in a dose-dependent manner. The formation of edema in mouse ears was reduced at the highest dose tested compared to the control. Moreover, in the acute toxicity test, no mortality occurred in mice administered 5,000 mg/kg body weight of SFEE over the 2-week observation period. These results suggest that SFEE may have significant effects on inflammatory factors and be a potential anti-inflammatory therapeutic material.

Insecticidal Activity of 16 Insecticides Against Phthorimaea operculella and It’s Effect On Reproduction

Jeong-Jin An,Young-Uk Park,Ki-Su Ahn,Hyun-Na Koo,Gil-Hah Kim 한국응용곤충학회 2012 한국응용곤충학회 학술대회논문집 Vol.2012 No.05

Insecticidal susceptibilities of 16 registered insecticides on each developmental stages of Phthorimaea operculella were investigated and further examined the contact, oral and residual toxicities after chosen from insecticides showing good effect. Mortality, longevity and effect on reproduction of 16 insecticides to P. operculella adults were also investigated. To the eggs and pupae, only spinosad showed 71.1% inhibition rate of egg hatch and 66.7% inhibition rate of emergence. To the 3rd nymphs, fenitrothion (LC50 336.6 ppm), esfenvalerate (LC50 8.6 ppm), ethofenprox (LC50 35.7 ppm), and emamectin benzoate (LC50 0.05 ppm) showed oral toxicity over 90% and esfenvalerate (LC50 0.87 ppm), ethofenprox (LC50 16.5 ppm), emamectin benzoate (LC50 0.53 ppm), and spinosad (LC50 2.48 ppm) showed the contact toxicity over 90%. To the adults, mortalities of insecticides were showed as below: deltamethrin and spinosad showed perfect mortality 48 h after treatment; esfenvalerate, ethofenprox, and thiamethoxam showed 40 - 60% mortalities; but the others are not showed any effect. Fecundities of female adults were inhibited by esfenvalerate, emamectin benzoate, and dinotefuran, compare to that of the control, but there were no statistical differences to that of ethofenprox, benfuracarb, thiamethoxam, clothianidin, and diflubenzuron. Adult longevity was showed no difference compare to that of the control. Residual effect of emamectin benzoate showed perfect insecticidal activity at 14 days after treatment and the next ethofenprox showed over 90% at 7 days after treatment.

Granulocytic and Monocytic Myeloid-Derived Suppressor Cells are Functionally and Prognostically Different in Patients with Chronic Myeloid Leukemia

Ahn Ari,Park Chan-Jeoung,Kim Min-sun,Cho Young-Uk,Jang Seongsoo,Bae Mi Hyun,Lee Jung-Hee,Lee Je-Hwan,Koh Kyung-Nam,Im Ho Joon 대한진단검사의학회 2021 Annals of Laboratory Medicine Vol.41 No.5

Myeloid-derived suppressor cells (MDSCs) represent phenotypically heterogeneous populations that suppress tumor-specific T-cell responses. MDSCs are produced from myeloid precursors in emergent states and are increased in several hematologic malignancies. We evaluated the differences in the levels and prognostic significance of MDSCs according to the clinical status of chronic myeloid leukemia (CML). The percentages and numbers of granulocytic (g)MDSCs and monocytic (m)MDSCs in peripheral blood (PB) and bone marrow (BM) aspirates were determined by five-color flow cytometry (HLA-DR/CD11b/CD15/CD33/CD14). The median BM-gMDSC% and PB-gMDSC% of the CML group were lower than those of the complete hematologic response (CHR) and control groups (P<0.001). In the CHR group, patients with major molecular response (MMR) showed higher median BM-gMDSC% than those without MMR (P=0.039). Conversely, the PB-mMDSC number of the CML group was higher than those of the CHR and control groups (P<0.001). Patients with high PB-gMDSC number exhibited superior survival to those with low PB-gMDSC number (P=0.021), and patients with high PB-mMDSC% showed inferior survival to those with low PB-mMDSC%, but there was no statistical significance (P=0.182). Increased gMDSCs at CHR may reflect non-leukemic granulopoiesis, and a high number of PB-gMDSCs suggests better prognosis in CML. However, mMDSCs may be associated with malignant conditions and poor prognosis.

Dependence of Photovoltaic Effects in Organic Semiconductors on the BCP Layer Thickness

Hyun Seok Oh,Tae Wan Kim,Dong-Kyu Lee,Ho Shik Lee,Joon Ho Ahn,Joon Ung Lee,Kyung Uk Jang,Won Jae Lee 한국물리학회 2006 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.48 No.6

We fabricated solar-cell devices based on zinc-phthalocyanine (ZnPc) as a donor (D) and fullerene (C60) as an electron acceptor (A) with doped charge transport layers and with bathocuproine (BCP) an exciton blocking layer (EBL). We measured the photovoltaic characteristics of the solar-cell devices by using a Xenon lamp as a light source. Several thicknesses of BCP were made between C60 and Al, and we obtained characteristic parameters such as the short-circuit current, the open-circuit voltage, and the power conversion efficiency of the device. With an EBL, the fill factor and the power conversion efficiency were 0.57 and 0.435 %, respectively, at 100 mW/cm2.pX=?

Plasma Treatment Effect on Dye-Sensitized Solar Cell Efficiency of Hydrothermal-Processed TiO2 Nanorods

Ahn, Kyun,Lee, Hyun-Uk,Jeong, Se-Young,Kim, Jong-Pil,Jin, Jong Sung,Ahn, Hyeong-Soo,Kim, Hong-Seung,Cho, Chae-Ryong American Scientific Publishers 2012 Journal of nanoscience and nanotechnology Vol.12 No.7

<P>Atmospheric plasma (AP) treatment was carried out on TiO2 nanorods (NRs) that were hydrothermally grown on F-doped SnO2 (FTO)/glass. The effects of AP treatment on the surface of the TiO2 NRs were investigated, where the treatment involved the use of the reactive gases H2, N2, and O2. The surface energy of AP-treated TiO2 NRs was about 1.5 times higher than that of untreated TiO2 NRs (364.3 mJ/m2). After AP treatment, the increase of the peak area ratios of the Ti2O3 and TiO2 peaks in the XPS spectra resulted in a decrease in the number of oxygen vacancies in the TiO2 NRs. The efficiency of a dye-sensitized solar cell (DSSC) based on the N2-plasma-treated TiO2 NRs, which was approximately 1.11%, was about 79% higher than that of a DSSC based on the untreated TiO2 NRs.</P>

An Experimental Study of the Air-side Particulate Fouling in Fin-and-Tube Heat Exchangers of Air Conditioners

Ahn, Young-Chull,Cho, Jae-Min,Shin, Hee-Soo,Hwang, Yu-Jin,Lee, Chang-Gun,Lee, Jae-Keun,Lee, Hyun-Uk,Kang, Tae-Wook 한국화학공학회 2003 Korean Journal of Chemical Engineering Vol.20 No.5

An experimental study was conducted to investigate the chronological performance variation such as pressure drop across a heat exchanger and cooling capacity due to the air-side particulate fouling of fin-and-tube heat exchangers for air conditioner evaporators used. Thirty samples of air conditioners used in the field such as inns, restaurants, and offices are collected in chronological order of use. This study was intended to provide factual long-term fouling data under actual operating conditions. It was found that the important parameters to influence the fouling of heat exchangers are the concentration and size of indoor pollutants, the filter efficiency, the hydrophilicity of fin surfaces, fin spacing, and the structure of fins. The pressure drop of heat exchangers increases from year to year due to the deposition of indoor pollutants larger than 1㎛ in size and increases up to 44% in the samples used for 7 years. Also, the air-side particulate fouling degrades the cooling capacity by 10-15% in the samples used for 7 years.