ATM망에서 ABR서비스를 위한 효율적인 전송률 할당 알고리즘에 관한 연구

천재호,윤상호,김명균,허정석 울산대학교 1999 공학연구논문집 Vol.30 No.2

ATM망에서 ABR 서비스는 CBR, VBR에 할당된 대역폭을 제외한 나머지를 이용해서 데이터를 전송한다. 오디오 또는 비디오 데이터와 같이 실시간 전송이 필요한 서비스들을 전송지연이 제한되는 CBR이나 VBR 트래픽을 이용하여 제공할 수 있지만, 이런 경우에는 전송 대역폭을 효율적으로 사용하지 못하는 단점이 있다. 본 논문에서는 실시간 데이터를 ABR 서비스를 이용하여 효율적으로 전송하기 위한 ABR 대역폭 할당 알고리즘을 제안한다. 제안된 알고리즘은 MCR을 보장하며, MCR에 비례해 전송률을 할당한다. 그리고 접속의 상태를 만족(satisfied)상태와 불만족(bottlenecked)상태로 구분하고, 만족 상태인 접속이 사용하지 않는 대역폭을 불만족 상태인 접속이 사용할 수 있도록 하여 대역폭 활용도를 높인다. 또한 제안된 알고리즘은 큐 제어 함수를 사용해서 큐 길이를 일정한 범위로 유지함으로써 셀의 전송지연을 일정하게 한다. 본 논문에서는 시뮬레이션을 통해 제안된 알고리즘의 성능을 분석하고, 기존에 제안된 ATM 포럼[1]및 Kalampoukas 알고리즘[2]과 비교를 하였다. On ATM networks, ABR services are provided using the remained bandwidth after allocating CBR and VBR traffic. Realtime services such as transmitting audio or video data may be provided using CBR and VBR which have a constrained transmission delay, but in those cases, the communications bandwidth may be wasted. This paper proposes an efficient ABR rate allocation algorithm to transfer real-time data using ABR service. The proposing algorithm guarantees MCR and allocates bandwidth to each connection proportional to its MCR. The proposing algorithm divides the connections in two groups, a satisfied state group and a bottlenecked state group, and enhances bandwidth utilization by allowing the remained bandwidth after allocating to the connections in the satisfied state to the connections in the bottlenecked state. The proposing algorithm uses the queue control function to keep the queue length within some boundary, which makes the transmission delay constant. We simulate and compare the performance of the proposing algorithm with that of the algorithms proposed by ATM Forum[1] and Kalampoukas[2].

물리학 선량법을 이용한 갑상선암의 개인별 최대안전용량 I-131 치료법 개발과 유용성 평가

김정철,윤정한,범희승,제갈영종,송호천,민정준,정환정,김성민,허영준,이명호,박영규,정준기 대한핵의학회 2003 핵의학 분자영상 Vol.37 No.2

목적 : 분화갑상선암 환자에 대한 방사성옥소(I-131) 치료는 재발율과 사망률을 감소시키는 효과적인 치료법이지만, 치료용량을 증가시킴으로써 치료율을 향상시킬 수 있는지에 대해서는 아직 논란이 있다. 본 연구에서는 최대허용선량 치료법의 효용성을 검증하고자 하였다. 대상 및 방법 : 임상적 병기가 제3, 4병기이고, 6개월 이후에 I-131 전신스캔(이하 IWBS)과 혈중 thyroglobulin (이하 Tg), anti-thyroglobulin antibody (이하 ATA), 초음파검사 (이하 US) 및 F-18 FDG PET 등을 통해 치료여부를 확인할 수 있었던 58명(남:여=9:49, 평균연령 50±11세)의 유두상갑상선암 환자를 대상으로 하였다. 이중 11명은 제4병기, 47명은 제3병기였으며, 43명(남:여=4:39), 평균연령 50±11세)은 7.4 GBq 이하의 고식적인 저용량치료법으로 치료하였고, 9.25 GBq 이상의 고용량 치료를 받은 환자는 15명(남:여=5:10, 평균연령 50±12세)으로 고용량군에서 남자가 더 많았으나 연령의 차이는 없었다. 고용량군 환자 모두에서 추적용량의 방사성옥소(평균 77±3 MBq)를 경구 투여한 후 혈중 방사능소실곡선을 통해 최대허용선량(maximum permissible dose, 이하 MPD)을 계산하였으며, 7명에서는 말초혈액림프구의 중기염색체분석법에 의해 생물학적으로 MPD를 계산하였다. 14명에서는 치료용량의 방사성옥소를 투여한 후 혈중 방사능소실곡선을 통해 MPD를 계사하였다. 완전치유(complete response, 이하 CR)는 IWBS에서 병소가 없어지고, 혈중 Tg치가 1 ng/mL 이하로 감소한 경우로 정의하였으며, 부분치유(partial response, 이하 PR)는 IWBS에서 병소가 없어졌더라도 혈중 Tg, ATA치가 높거나, US 또는 PET 검사에서 병소가 남아있는 경우로 정의하였다. 치료후 IWBS에서 병소가 오히려 증가하거나 변함없는 경우는 없었다. 방사성옥소 치료에 의한 부작용은 입원기간 중 타액선이 현저하게 붓고 통증이 있거나, 구토를 심하게 하는 경우, 그리고 퇴원후 1개월째 백혈구수가 20% 이상 감소한 경우로 정의하였다. 결과 : 양 군간에 연속적인 수치변화를 비교하는 경우는 paired t-test를 이용하였으며, 대상군간 치료효과와 부작용의 비교는 chi-square test를 이용하였다. p값 0.05 미만을 통계적으로 유의한 차이로 인정하였다. 고용량군 환자 모두에서 추적용량과 치료용량의 방사성옥소 투여 후 혈액의 피폭선량은 각각 0.012±0.3 Gy, 1.66±25 Gy였으며, 방사성옥소 투여 후 혈액에 전달되는 피폭선량은 추적용량보다 치료용량에서 더 많았고 (1.21: 166 rad, p<0.001), 방사성옥소 1 mCi당 혈액에 전달되는 피폭선량은 차이가 없었다(0.58±0.1 vs. 0.56±0.1 rad/37 MBq, p=0.34). 추적용량 방사성옥소 투여 후 구한 MPD는 평균 13.3±1.9 GBq (9.7 ~ 16 GBq) 이였고, 치료용량 방사성옥소 투여 후 구한 MPD는 평균 13.8±2.1 GBq (10.4 ~ 16.3 GBq)로 유의한 차이가 없었으며 (p=0.20), 두 수치간에는 유의한 상관 관계가 있었다(r=0.8, p<0.0001). 7명의 환자에서 말초혈액림프구 중기염색체 분석법으로 MPD를 측정하였는데 혈액의 피폭선량은 1.78±0.03 G였으며, 같은 환자에서 혈중 방사능소실곡선으로부터 구한 피폭선량은 1.54±0.03 G로 유의하게 낮았으나 (p=0.01), 두 측정치 간에는 유의한 상관관계(r=0.86, p=0.01)가 있었다. 저용량 치료군 43명 중 22명(51.2%)에서 완전치유를 보였고 21명(48.8%)에서는 부분치유를 보인 반면 고용량 치료군 15명 중 12명(80%)에서 완전치유를 보였고 3명(20%)에서만 부분치유를 보여 고용량 치료군에서 유의하게 높은 완전치유를 얻을 수 있었다(p=0.05). 한편 부작용 발생빈도는 저용량 치료군 43명 중 13(30.2%), 고용량 치료군 15명 중 6명(40%)로 양군간에 유의한 차이가 없었다(p=0.46). 임상적인 병기, 연령 및 성별에 따라서는 치유의 차이가 없었다(p>0.05). 결론 : 혈중소실곡선으로부터 MPD를 결정하고 이를 토대로 환자 개개인별로 적절한 선량을 선택하여 치료하는 방법은 부작용을 최소화하면서도 치료효과를 높일 수 있는 매우 유용한 치료법이며, 고위험군 분화갑상선 암 환자에게 가장 적절한 치료법이라고 사료되었다. Purpose: Radioiodine (1-131) therapy is an effective modality to reduce both recurrence and mortality rates in differentiated thyroid cancer. Whether higher doses shows higher therapeutic responses was still debatable. The purpose of this study was to validate curve-fitting (CF) method measuring maximum permissible dose (MPD) by a biological dosimetry using metaphase analysis of peripheral blood lymphocytes. Materials and Methods: Therapeutic effects of MPD was evaluated in 58 patients (49 females and 9 males, mean age 50±11 years) of papillary thyroid cancer. Among them 43 patients were treated with ≤7.4 GBq, while 15 patients with ≥9.25 GBq. The former was defined as low-dose group, and the latter high-dose group. Therapeutic response was defined as complete response when complete disappearance of lesions on follow-up 1-131 scan and undetectable serum thyroglobulin levels were found. Statistical comparison between groups were done using chi-square test. P value less than 0.05 was regarded as statistically significant. Results: MPD measured by CF method using tracer and therapeutic doses were 13.3±1.9 and 13.8±2.1 GBq, respectively (p=0.20). They showed a significant correlation (r=0.8, p<0.0001). Exposed doses to blood measured by CF and biological methods were 1.54±0.03 and 1.78±0.03 Gy (p=0.01). They also showed a significant correlation (r=0.86, p=0.01). High-does group showed a significantly higher rate of complete response (12/15, 80%) as compared to the low-dose group (22/43, 51.2%) (p=0.05). While occurrence of side effects was not different between two groups (40% vs. 30.2%, p=0.46). Conclusion: Measurement of MPD using CF method is reliable, and the high-dose 1-131 therapy using MPD gains significantly higher therapeutic effects as compared with low-dose therapy.

자가 면역성 간염에서 자가항체의 발현 양상과 스테로이드 치료의 효과

박기오,채경훈,허원석,강윤세,정재훈,김연수,문희석,이엄석,김선문,이병석,김남재,이헌영 충남대학교 의과대학 의학연구소 2003 충남의대잡지 Vol.30 No.1

목적 : 최근 8년간 본원에서 경험한 자기면역성 간염의 혈액학적 특징과 스테로이드의 치료효과를 알아보고자 본 연구를 시행하였다. 방법 : 1996년 이후부터 2002년까지 충남대학교 병원에서 1999년 International Autoimmune Hepatitis Group(LAHG)에서 제시한 수정 진단 기준안에 의거하여 총 진단점수가 probable 이상에 해당하는 환자들을 대상으로 임상적 특징, 검사실 및 조직 소견과 스테로이드와 azathioprine의 치료 효과를 후향적으로 조사하였다. 결과 : 9예의 환자들은 여성이 78%, 40대가 많았고, 급성 발병이 33.3%, 피로감, 식욕부진 및 황달 등이 나타났으며, 항핵항체가 55.6%에서 그리고 항평활근 항체가 77.8%에서 양성이었고, 동반 질환은 류마치스 관절염이 2예, 특발성 혈소판 감소증 1예, Henoch-Sch nlein 자반증 및 그레브스병이 각각 1예 씩이었다. 7예에 대해서 스테로이드와 azathioprine으로 치료하여 생화학적 임상적 완해가 이루어져서 유효한 치료 결과를 얻었다. 결론 : 자가면역성 간염은 우리 나라에서 원인을 찾을 수 없는 만성 간질환의 경우, 특히 중년여성에서 다른 자가면역성 질환이 동반되었을 때 자가면역성 간염을 의심하여 자가항체 선별검사를 시행해 보아야 할 것으로 생각된다. 향후 다기관 연구를 통하여 좀 더 많은 증례를 모으고 전향적인 연구를 시행하여야 할 필요가 있다. Although autoimmune hepatitis(AIH) is common in western contries, some studties have been reported in Korea. The aim of the study was to analyze the clinical and histological features and expression pattern of the autoantibody and to examine clinical course of AIH in Korea. For 9 patients diagnosed as having AIH in our hospital since 1996, we reviewed medical records and analyzed clinical and laboratory findings retrospectively. They had a probable or definite AIH according to the revised criteria of International AIH group. The mean age was 42.7(21∼68)years and 7(77.8%) were female. Three of them(33.3%) showed acute hepatitis and five of them showed cirrhosis. Fatigue and anorexia were the most frequently complained symptoms(55.6%). Four patients(44.4%) were accompanied with other autoimmune diseases. Antinuclear antibody was detected in 5(55.6%) and anti-smooth muscle antibody was detected in 7(77.8%). Three patients showed focal picemeal necrosis and four showed periportal fibrosis. Among 7 patients who received immunosuppressive therapy, six patients(85.7%) showed initial response. and biochemical and serologic remission were achived in 5(71.4%) and 3(42.8%) patients, AIH seems to be partly responsible for chronic liver disease of unknown etiology in Korea. AIH should be suspected in female patients with unknown chronic liver disease of unknown etiolgy, especially accompanied with other autoimmune disease. The clinical characteristics of AIH may not be quite different from those of Western countries.

HCC : Clinical utility of gadoxetic acid-enhanced MRI versus multiphase multidetector row computed tomography for predicting recurrence of hepatocellular carcinoma treated with radiofrequency ablation (초)

( Jung Im Jung ),( Heo Jung ),( Young Hwa Jo ),( Yong Wan Sung ),( Hyun Young Woo ),( Ki Tae Yoon ),( Gwang Ha Kim ),( Dae Hwan Kang ),( Geun Am Song ),( Mong Cho ) 대한간학회 2011 Clinical and Molecular Hepatology(대한간학회지) Vol.17 No.3(S)

Preferential growth of boron layer in magnesium diboride (MgB₂) by Mg diffusion method

Heo, Yoon-Uk,Yoon, Sangmoon,Kim, Jung Ho,Kim, Young-Ki,Kim, Miyoung,Song, Tae-Jin,Maeda, Minoru,Dou, Shi Xue Elsevier 2017 Journal of alloys and compounds Vol.725 No.-

<P><B>Abstract</B></P> <P>Growth mechanism and grain boundary (GB) contact of polycrystalline MgB<SUB>2</SUB> fabricated by Mg diffusion method are studied by STEM and EELS analyses. In contrast to the previous reports based on the computational calculation, preferential growth of (001) boron (B) layer and the B-B contact at MgB<SUB>2</SUB> GBs are confirmed by annular dark field (ADF) –STEM image and the combined EELS analyses. The effect of B-B contact at the GB on the superconductivity is further evaluated using First principles calculation. Superior GB linkage of the supercurrent flow via GB B-B contact is expected from the calculated density of states at Fermi level. B-terminated growth mechanism in Mg diffusion method and the effect of GB connectivity via B-B and Mg-Mg contacts are discussed. Finally, we suggest a model of GB linkage of supercurrent flow via B-B contact in polycrystalline MgB<SUB>2</SUB>.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Preferential growth of boron in polycrystalline MgB<SUB>2</SUB> has been firstly confirmed. </LI> <LI> The B-terminated growth mechanism of an MgB<SUB>2</SUB> has been suggested. </LI> <LI> The GB linkage via B-B contact in polycrystalline MgB<SUB>2</SUB> has been elucidated. </LI> </UL> </P>

The comparison of surgical outcomes and learning curves of radical hysterectomy by laparoscopy and robotic system for cervical cancer: an experience of a single surgeon

( Yoon Jung Heo ),( Seongmin Kim ),( Kyung Jin Min ),( Sanghoon Lee ),( Jin Hwa Hong ),( Jae Kwan Lee ),( Nak Woo Lee ),( Jae Yun Song ) 대한산부인과학회 2018 Obstetrics & Gynecology Science Vol.61 No.4

Objective The aim of this study was to compare and determine the feasibility, surgical outcomes, learning curves of robotic radical hysterectomy with lymph node dissection (RRHND) to conventional laparoscopic radical hysterectomy with lymph node dissection (LRHND) performed by a single surgeon, in patients with cervical cancer. Methods Between April 2009 and March 2013, 22 patients underwent LRHND and 19 patients underwent RRHND. Variables such as age, body mass index, International Federation of Gynecology and Obstetrics stage, histological results, number of dissected lymph nodes, operative time, estimated blood loss, days of hospitalization and complications were reviewed. Learning curves of operation time was obtained using cumulative sum (CUSUM) method. Results Both groups showed similar patient and tumor characteristics. In surgical outcome analysis, RRHND (51.8±10.4 minutes) showed longer preparing time than LRHND (42.5±14.1 minutes). In the LRHND group, 8 patients experienced postoperative complications (5 void difficulty, 1 postoperative bleeding, 1 right basal ganglia infarction, 1 fever). On the other hand, in the RRHND group, 4 patients experienced a postoperative complication (2 bleeding, 1 peritonitis, 1 dehiscence of trocar site). Using CUSUM method, the learning curves were obtained by plotting the cumulative sequential differences between each data point and the average operation time, and showed two distinct phases in both type of operations. Conclusion RRHND would be appropriate surgical approach in patients with cervical cancer with favorable outcome of less voiding difficulty. A minimum of 13 cases of robotic radical hysterectomies are required to achieve surgical improvement in the treatment of cervical cancer.

Induction of Neurogenic Potency of Human Adipose Tissue-derived Stem Cells by Hypoxia at a High Cell Density

Yoon Jung HEO,So Hyun KIM,Jeein CHOI,Sookyung KANG,Sungsu PARK 한국생물공학회 2012 한국생물공학회 학술대회 Vol.2012 No.4

Methionine sulfoxide reductase B1 deficiency does not increase high-fat diet-induced insulin resistance in mice

Heo, Jung-Yoon,Cha, Hye-Na,Kim, Ki Young,Lee, Eujin,Kim, Suk-Jeong,Kim, Yong-Woon,Kim, Jong-Yeon,Lee, In-Kyu,Gladyshev, Vadim N.,Kim, Hwa-Young,Park, So-Young Harwood Academic 2017 Free radical research Vol.51 No.1

Chromogenic Tubular Polydiacetylenes from Topochemical Polymerization of Self-Assembled Macrocyclic Diacetylenes

Heo, Jung-Moo,Kim, Youngmee,Han, Seulki,Joung, Joonyoung F.,Lee, Sang-hwa,Han, Sejin,Noh, Jaegeun,Kim, Jaeyong,Park, Sungnam,Lee, Haiwon,Choi, Yoon Mi,Jung, Young-Sik,Kim, Jong-Man American Chemical Society 2017 Macromolecules Vol.50 No.3

<P>Tubular materials formed by self-assembly of small organic molecules find great utility in chemical and material science. Conventional tubular structures often lack stability because non covalent molecular interactions are responsible for their conformational integrities. Herein we report the development of covalently linked chromogenic organic nanotubes which are prepared by using topochemical polymerization of self-assembled macrocyclic diacetylenes (MCDAs). Crystal structures of five MCDAs having different diameters were elucidated, and four of these substances were transformed to tubular polydiacetylenes (PDA) by UV-induced polymerization. Surprisingly, MCDA-1 was found to self-assemble in stacks with a tilt angle of 62.1 degrees which significantly deviates from the optimal value for polymerization of 45 degrees. This observation suggests that geometric parameters derived using linear diacetylene (DA) models might not be strictly applicable to polymerization of MCDA systems. Blue-phase PDAs obtained by polymerization of MCDA-1 and MCDA-3 have different thermochromic and solvatochromic properties, which enable them to be utilized for colorimetric differentiation of aromatic solvents including isomeric xylenes. The observations made and information obtained in this study should enhance the understanding and design of stimulus-responsive rigid organic nanotubes.</P>

Effect of fermented red ginseng on gut microbiota dysbiosis- or immobilization stress-induced anxiety, depression, and colitis in mice

Yoon-Jung Shin,Dong-Yun Lee,Joo Yun Kim,Keon Heo,Jae-Jung Shim,Jung-Lyoul Lee,Dong-Hyun Kim The Korean Society of Ginseng 2023 Journal of Ginseng Research Vol.47 No.2

Background: Red ginseng (RG) alleviates psychiatric disorders. Fermented red ginseng (fRG) alleviates stress-induced gut inflammation. Gut dysbiosis causes psychiatric disorders with gut inflammation. To understand the gut microbiota-mediated action mechanism of RG and fRG against anxiety/depression (AD), we investigated the effects of RG, fRG, ginsenoside Rd, and 20(S)-β-D-glucopyranosyl protopanaxadiol (CK) on gut microbiota dysbiosis-induced AD and colitis in mice. Methods: Mice with AD and colitis were prepared by exposing to immobilization stress (IS) or transplanting the feces of patients with ulcerative colitis and depression (UCDF). AD-like behaviors were measured in the elevated plus maze, light/dark transition, forced swimming, and tail suspension tests. Results: Oral gavage of UCDF increased AD-like behaviors and induced neuroinflammation, gastrointestinal inflammation, and gut microbiota fluctuation in mice. Oral administration of fRG or RG treatment reduced UCDF-induced AD-like behaviors, hippocampal and hypothalamic IL-6 expression, and blood corticosterone level, whereas UCDF-suppressed hippocampal BDNF⁺NeuN⁺ cell population and dopamine and hypothalamic serotonin levels increased. Furthermore, their treatments suppressed UCDF-induced colonic inflammation and partially restored UCDF-induced gut microbiota fluctuation. Oral administration of fRG, RG, Rd, or CK also decreased IS-induced AD-like behaviors, blood IL-6 and corticosterone and colonic IL-6 and TNF-α levels, and gut dysbiosis, while IS-suppressed hypothalamic dopamine and serotonin levels increased. Conclusion: Oral gavage of UCDF caused AD, neuroinflammation, and gastrointestinal inflammation in mice. fRG mitigated AD and colitis in UCDF-exposed mice by the regulation of the microbiota-gut-brain axis and IS-exposed mice by the regulation of the hypothalamic-pituitary-adrenal axis.