• 대한전자공학회논문지TC
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• 제40권12호
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• pp.83-93
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• 2003

IP 망에서의 차별 서비스 구조는 품질 보장 서비스를 위해 대역폭 브로커를 기반으로 QoS프로비저닝의 제어 및 관리를 수행한다. 그러나, 이러한 대역폭 브로커는 모든 입구 에지 노드로 유입되는 호의 연결 수락 제어를 위해 중앙 집중형 자원 관리를 수행함에 따라 확장성 면에서 큰 단점을 갖는다. 본 논문에서는 대역폭 브로커를 갖는 차별 서비스 구조에서 확장성을 높이고 유입되는 호의 상태를 반영한 적응적 연결 수락 제어 메커니즘을 제안하고자 한다. 이를 위해 대역폭 브로커의 기능을 입구 에지 노드와 분리해서 자원 관리 및 프로비저닝을 대역폭 브로커에서 수행하고, 입구 에지 노드에서는 연결 수락 제어를 담당한다. 입구 에지 노드에서는 연결 수락제어를 위해 각 에지 노드간 패스 개념을 도입하고, 패스 단위로 할당된 대역 기반으로 연결 수락 제어를 수행한다. 패스 별 할당 대역량은 유입되는 트래픽에 따라 적응적으로 변화하게 되며 이는 대역록 브로커와의 통신을 최소화하면서 대역 자원의 효율적인 사용을 가능케 한다. 본 논문에서는 이러한 적응적 연결 수락 메커니즘을 제안하고 성능 분석을 통한 효율성 및 확장성의 개선을 제시하고자 한다.

• 대한전자공학회논문지TC
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• 제40권12호
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• pp.46-58
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• 2003

최근의 인터넷은 기존의 최선형 서비스구조(best-effort)에서 벗어나 별도의 차별화 된 트래픽 처리와 서비스품질(QoS)을 요구하는 응용들을 지원할 수 있는 네트워크 구조 및 트래픽 엔지니어링 기술을 요구하고있다. 더욱이 유선에서 무선으로 인터넷이 확장되면서 위치-종속적이며 버스트하게 발생되는 에러로 인해 기존의 패킷 스케줄링 방법으로는 정의된 서비스 품질을 제공할 수 없다. 따라서 본 논문에서 무선 인터넷 차별화 서비스 네트워크 환경에서도 정의된 서비스 품질을 제공할 수 있는 WDSPS(Wireless DiffServ Packet Scheduling) 스케줄링 알고리즘을 제안한다. 제안된 스케줄링 알고리즘은 무선망 에러로 생기는 클래스 큐의 블록킹 문제를 해결하고, 차별화 서비스 망에서 요구하는 각 클래스간 패킷 처리율, 패킷 지연, 패킷 손실률 등의 관점에서 차별화 서비스를 제공하며, 클래스 및 플로우간 효율적인 보상 방법으로 서비스 보상이 점진적으로 이루어져 하나의 클래스 및 플로우가 독점적으로 무선자원을 사용하지 못하도록 하였다. 모의 실험에서는 제안된 WDSPS 스케줄링 방법을 사용하여 다양한 무선 환경에서 서비스 클래스간 차별화 된 서비스를 제공하며 전체 서비스 처리율을 향상시킬 수 있음을 보였다.

• Asian Pacific Journal of Cancer Prevention
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• 제16권17호
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• pp.7541-7546
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• 2015

Aim: To report the histologic findings on Whipple resection specimens and thus determine the extent and spread of carcinomas of ampullary region and head of pancreas in our population. Setting: Section of Histopathology, Department of Pathology, Aga Khan University Hospital (AKUH), Karachi, Pakistan. Materials and Methods: A case series of 311 consecutive Whipple resection specimens received between January 1,2003 and December 31, 2014. Specimens processed for histologic sections and representative sections submitted and histologically examined as per established and standard protocols. All relevant tumor parameters including histologic type, histologic grade, pathologic T and N stage and tumor size were assessed. Epidemiologic data were also recorded. All findings were analysed using SPSS 19.0 software. Results: Ampullary (periampullary) carcinomas were much more common than carcinomas of the head of the pancreas, especially in males, with an average age of 53 years. Mean tumor size was 2.5 cms, over 54% were well differentiated. A large majority were pT2 or pT3 and N0. Carcinomas of pancreatic head were also more common in males, mean age was 55 years, mean tumor size was 3.5cms, and over 65% were moderately differentiated. The majority were T2 or T3 and pN1. Prognostically, significant statistical correlation was seen with tumor grade and pathologic T and N stage (p values statistically significant). However, tumor size was not statistically significant. Conclusions: Ampullary carcinomas are more common compared to pancreatic carcinomas. Majority of ampullary carcinomas were well differentiated while majority of pancreatic carcinomas were moderately differentiated. Large majority of both types of cases were pT2 or T3. Histologic tumor grade and pathologic T and N stage are significantly related to prognosis in Pakistani patients with ampullary and pancreatic cancers.

• Asian Pacific Journal of Cancer Prevention
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• 제13권4호
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• pp.1453-1456
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• 2012

Background: Prostate cancer is the most common malignant tumour in men and the second most common cause of male cancer death. The study examines the clinicopathological features of patients with prostate cancer consecutively diagnosed at a private Diagnostic Radiology Centre in Western Jamaica over a 6-year period. Method: The medical records, including the pathology reports of 423 consecutive patients who had transrectal ultrasonography (TRUS) - guided prostate biopsy between January 2006 and December 2011 were reviewed. Results: The mean age at diagnosis of the 191 men with prostate adenocarcinoma was $68.5{\pm}0.59$ years with the majority in the 70 - 79 year age group (43.5%). Moderately differentiated carcinomas (Gleason score of 6) comprised the largest group with 72 cases (37.9%); poorly differentiated cancers with Gleason scores of 8 - 10 comprised 49 cases (25.8%). The PSA levels increased with Gleason score. The mean PSA levels for men with Gleason score of 6 was $50.1{\pm}30.0$ ng/mL compared with $136.5 {\pm}59.9$ ng/mL in patients with Gleason score of 8 and $140.5{\pm}31.8$ ng/mL in patients with Gleason score of 9. Perineural invasion was present in 7.85% of the cases overall; high-grade prostatic intraepithelial neoplasia (HGPIN) was present in 4.71% of the biopsies. Conclusion: Although the majority of patients had moderate, and moderate to poor differentiated carcinomas, the number with poorly differentiated carcinoma was high. This is a reflection of the patients' late clinical presentation at the time of diagnosis.

• Asian Pacific Journal of Cancer Prevention
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• 제14권11호
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• pp.6727-6731
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• 2013

Homologous recombination (HR) repair has a crucial role to play in the prevention of chromosomal instability, and it is clear that defects in some HR repair genes are associated with many cancers. To evaluate the potential effect of some HR repair gene polymorphisms with differentiated thyroid carcinoma (DTC), we assessed Rad51 (135G>C), Rad52 (2259C>T), XRCC2 (R188H) and XRCC3 (T241M) polymorphisms in Iranian DTC patients and cancer-free controls. In addition, haplotype analysis and gene combination assessment were carried out. Genotyping of Rad51 (135G>C), Rad52 (2259C>T) and XRCC3 (T241M) polymorphisms was determined by PCR-RFLP and PCR-HRM analysis was carried out to evaluate XRCC2 (R188H). Separately, Rad51, Rad52 and XRCC2 polymorphisms were not shown to be more significant in patients when compared to controls in crude, sex-adjusted and age-adjusted form. However, results indicated a significant difference in XRCC3 genotypes for patients when compared to controls (p value: 0.035). The GCTG haplotype demonstrated a significant difference (p value: 0.047). When compared to the wild type, the combined variant form of Rad52/XRCC2/XRCC3 revealed an elevated risk of DTC (p value: 0.007). It is recommended that Rad52 2259C>T, XRCC2 R188H and XRCC3 T241M polymorphisms should be simultaneously considered as contributing to a polygenic risk of differentiated thyroid carcinoma.

• Archives of Plastic Surgery
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• 제39권6호
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• pp.593-599
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• 2012

Background This study aimed to investigate the possibility of isolating mesenchymal stem cells (MSCs) from human thigh adipose tissue and the ability of human thigh adipose stem cells (HTASCs) to differentiate into hepatocytes. Methods The adipose-derived stem cells (ADSCs) were isolated from thigh adipose tissue. Growth factors, cytokines, and hormones were added to the collagen coated dishes to induce the undifferentiated HTASCs to differentiate into hepatocyte-like cells. To confirm the experimental results, the expression of hepatocyte-specific markers on undifferentiated and differentiated HTASCs was analyzed using reverse transcription polymerase chain reaction and immunocytochemical staining. Differentiation efficiency was evaluated using functional tests such as periodic acid schiff (PAS) staining and detection of the albumin secretion level using enzyme-linked immunosorbent assay (ELISA). Results The majority of the undifferentiated HTASCs were changed into a more polygonal shape showing tight interactions between the cells. The differentiated HTASCs up-regulated mRNA of hepatocyte markers. Immunocytochemical analysis showed that they were intensely stained with anti-albumin antibody compared with undifferentiated HTASCs. PAS staining showed that HTASCs submitted to the hepatocyte differentiation protocol were able to more specifically store glycogen than undifferentiated HTASCs, displaying a purple color in the cytoplasm of the differentiated HTASCs. ELISA analyses showed that differentiated HTASCs could secrete albumin, which is one of the hepatocyte markers. Conclusions MSCs were islolated from human thigh adipose tissue differentiate to heapatocytes. The source of ADSCs is not only abundant abdominal adipose tissue, but also thigh adipose tissue for cell therapy in liver regeneration and tissue regeneration.

• Radiation Oncology Journal
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• 제34권3호
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• pp.216-222
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• 2016

Purpose: To evaluate the benefit of adjuvant radiation therapy (RT) for retroperitoneal liposarcoma (RPLS) following gross tumor removal. Materials and Methods: We reviewed 77 patients with primary RPLS surgically treated between January 2000 and December 2013. Cases with gross residual disease were excluded. Tumor grade was evaluated according to the French Federation of Cancer Centers Sarcoma Group (FNCLCC) system. Adjuvant RT was delivered to 32 patients (42%) using external beam RT alone. Median follow-up time was 36 months (range, 5 to 169). Results: Among 77 patients, 33 (43%) presented with well-differentiated, 31 (40%) with de-differentiated, 8 (10%) with myxoid/round and 4 (5%) with pleomorphic morphology. The RT group included less well-differentiated subtype than surgery group (28% vs. 53%). During follow up, 34 patients (44%) showed local recurrence. Local recurrence rate was lower in the RT group (38%) compared to the surgery group (49%). The 3-year local control rate (LC) was 55.6%, and the 3-year overall survival (OS) was 82.1%. Tumor histology and FNCLCC grade were significantly associated with local recurrence. There was no statistical significance of adding adjuvant RT in LC (p = 0.312). However, patients with tumor histology other than well-differentiated subtype showed marginally decreased local recurrence rate after adjuvant RT (3-year LC, RT 43.9% vs. no RT 35.3%; p = 0.087). Conclusion: RPLS patients receiving RT experienced less local recurrence. We suggest that the addition of adjuvant RT may be related to improvement of LCs, especially in patients with non-favorable histologic subtypes.

• 한국학교수학회논문집
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• 제17권4호
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• pp.465-492
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• 2014

본 연구에서는 수학과 수업에 적용할 수 있는 지도 방법으로서 수준별 협동학습 학습지를 활용한 수준별 수업과 소집단 협동학습에서 그 효과를 알아보는데 목적이 있다. 이를 위해서 구체적인 연구문제를 살펴보면 다음과 같다. 첫째, 수준별 협동학습 학습지를 활용한 학급 내 수준별 협동학습으로 학생들의 수학의 학업성취도를 향상시킬 수 있는가? 둘째, 수준별 협동학습 학습지를 활용한 학급 내 수준별 협동학습으로 수학 교과에 대한 흥미와 자신감을 갖도록 하여 협동학습 태도를 향상시킬 수 있는가? 셋째, 수준별 협동학습 학습지를 활용한 학급 내 수준별 협동학습에 대한 학생들의 반응은 어떠한가? 이다. 연구결과로는 첫째, 실험집단은 비교집단에 비하여 학업성취도에 향상을 보여 주었다. 둘째, 실험집단은 비교집단에 비하여 협동학습 태도의 변화에 도움이 되었다. 셋째, 수준별 협동학습 학습지를 활용한 학급 내 수준별 협동학습으로 실험집단은 비교집단에 비하여 의미 있는 반응을 나타내었다.

• Asian Pacific Journal of Cancer Prevention
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• 제13권5호
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• pp.2335-2338
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• 2012

Objective: To evaluate several metabolic changes in patients with differentiated thyroid carcinoma (DTC ) which enhance cardiovascular risk in the western region of Nepal. Materials and Methods: This hospital based case control study was carried out using data retrieved from the register maintained in the Department of Biochemistry of the Manipal Teaching Hospital, Pokhara, Nepal between $1^{st}$ January, 2009 and $31^{st}$ December, 2011. The variables collected were age, gender, BMI, glucose, insulin, HbA1C, CRP, fibrinogen, total cholesterol, triglycerides, HDL, LDL, VLDL, f-T3, f-T4, TSH. One way ANOVA was used to examine statistical significance of differences between groups, along with the Post Hoc test LSD for comparison of means. Results: fT3 values were markedly raised in DTC cases ($5.7{\pm}SD1.4$) when compared to controls ($2.2{\pm}SD0.9$). Similarly, fT4 values were also moderately raised in cases of DTC ($4.9{\pm}SD1.3$ and $1.7{\pm}SD0.9$). In contrast, TSH values were lowered in DTC cases ($0.39{\pm}SD0.4$) when compared to controls ($4.2{\pm}SD1.4$). Mean blood glucose levels were decreased while insulin was increased and HDL reduced ($39.5{\pm}SD4.7$ as compared to the control $43.1{\pm}SD2.2$). Conclusion: Cardiovascular risk may be aggravated by insulin resistance, a hypercoagulable state, and an atherogenic lipid profile in patients with differentiated thyroid cancer.

• 정보처리학회논문지C
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• 제9C권4호
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• pp.505-512
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• 2002

사용자가 요구하는 서비스들은 그들의 QoS에 따라 다양하게 분류되어질 수 있으며, 이렇게 각기 다른 특성을 갖는 서비스들이 네트워크 상에 발생할 수 있는 장애 상황에 대처하여 안전하고 효율적인 서비스를 제공하기 위해서는 이들 연결에 대한 재라우팅(rerouting) 기법이 사용되어야 한다. 본 논문은 장애가 발생할 수 있는 IP 네트워크 상에서 차별화 된 서비스 제공을 위해 각 서비스들의 QoS에 따라 이들의 우선순위를 분류하고 이에 맞는 재라우팅 기법을 연구하고자 한다. 이를 위해서 재라우팅을 시작하는 시작점에 따라 Source Rerouting, Link Rerouting 기법을, 재라우팅을 수행하는 시간에 따라 Immediate Rerouting, Random Rerouting을 연구하여 이들에 대한 효과적인 orthogonal 관계에 대한 연구를 통해 서비스의 우선순위에 따라 보다 높은 성능을 갖는 DRIT와 DRDT 재라우팅 기법을 연구하고자 한다 결과적으로 차별화 된 서비스를 지원하기 위해 각 재라우팅 기법을 차별적으로 적용한 DRDT 보다 높은 성능을 보이고 있다.