• Radiation Oncology Journal
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• v.18 no.1
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• pp.17-25
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• 2000

Purpose : To evaluate the side effects, pattern of failure, and survival rate according to the sequence of postoperative adjuvant radiotherapy and chemotherapy, patients with stages II and III rectal cancer who had undergone curative resection were randomized to 'early radiotherapy group (arm I)' or' late radiotherapy group (arm II)', then we intend to determine the most effective sequence of the radiotherapy and chemotherapy. Materials and Methods . From January 1996 to March 1999, 313 patients with curatively resected stages II and III rectal cancer have been randomized to' early' or' late' radiation therapy group and received combined chemotherapy (5-FU 375 mg/m$^{2}$/day, ieucovorin 20 mg/m$^{2}$, IV bolus daily Dl-5, 8 cycles) and radiation therapy (whole pelvis with 45 Gy/25 fractions/s weeks). Arm I received radiation therapy from day 1 with first cycle of chemotherapy and arm II received radiation therapy from day 57 with third cycle of chemotherapy after completion of first two cycles. Preliminary analysis was peformed with 228 patients registered up to Jun 1998. Two out of the 228 patients were excluded because of double primary cancer. Median follow-up period was 23 months. Results :Local recurrence occurred in 11 patients (9.7$\%$) for arm I and 9 patients (8$\%$) for arm 11. There was no significant difference between both groups ( p=0.64). However, distant metastasis was found in 22 patients (19.5$\%$) for arm I and 35 patients (31.0$\%$) for arm II and which showed statistically significant difference between the two groups ( p=0.046). And neither 3-year disease-free survival (70.2$\%$ vs 59.2$\%$, p=0.2) nor overall survival (89.4$\%$ vs 88.0$\%$, p=0.47) showed significant differences. The incidence of leukopenia during radiation therapy and chemotherapy was 78.3$\%$ and 79.9$\%$ respectively but leukopenia more than RTOG grade 3 was only 2.1$\%$ and 6.0$\%$ respectively. The incidence of diarrhea more than 10 times per day was significantly higher in the patients for arm I than for arm II (71.2$\%$ vs 41.6$\%$, p=0.02) but this complication was controlled with supportive cares. Conclusion : Regardless of the sequence of postoperative adjuvant radiation therapy and chemotherapy after curative resection for rectal cancer, local recurrence rate was low with combined chemoradlotherapy. But distant metastasis rate was lower in early radiation therapy group than in late radiation therapy group and the reason is unclear. Most patients completed these treatments without severe complication, so these were thought to be safe treatments but the treatment compliance should be improved.

• Childhood Kidney Diseases
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• v.3 no.1
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• pp.72-79
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• 1999

Renal scarring associated with vesico-ureteral reflux(VUR) is one of the major causes of end stage renal failure and renal hypertension in children. Urinary ${\beta}_2$-microglobulin(MG) has been suggested as a potential marker for presence of renal tubular damage. This study was designed to evaluate the significance of random urine ${\beta}_2$-MG as a predictor of presence of vesico-ureteral reflux in children with urinary tract infection(UTI). 57 children with urinary tract infection were studied. Patients were devided into two groups; 35($78.9\%$) children have UTI without VUR and 12($21.1\%$) children have UTI and VUR. Beta2-MG and creatinine in random urine sample was measured to decide the excretion ratio(${\beta}_2$-MG/creatinine). Among the 57 children with UTI, 44 children were confirmed by urine culture study and 13 children suspected by compatible clinical feature. Random urine ${\beta}_2$-MG of VUR group ($2.2{\pm}5.91$ mg/L) were significantly higher than that of simple UTI group($0.19{\pm}0.16mg/L$)(P=0.03). The ${\beta}_2$-MG/creatinine ratio of VUR group($32.41{\pm}25.7$) were significantly higher than that of simple UTI group($3.93{\pm}3.44$)(P=0.007). In conclusion, random urine ${\beta}_2$-MG and excretion ratio deserved early predictor of presence of VUR in children with UTI. And this method was more simple and inexpensive than the method of measuring ${\beta}_2$-MG with 24 hour urine collection, so might be a useful screening test for VUR in children with UTI.

• Korean Security Journal
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• no.14
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• pp.517-534
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• 2007

Since the beginning of human society, there have always been struggles and competitions for survival and prosperity, terrorism is not a recent phenomenon, however in modern times it has progressed to reflect the advances in civilization and power structures. At the time of the 9.11 terrorist attacks in the U.S. A., a new world order was in the process of being established after the breakdown of the Cold War era. The attacks drove both the Western and the Islamic worlds into heightened fear of terrorism and war, which threatened the quality of life of the whole mankind. Through two war campaigns against the Islamic world, it seems the U.S. has been pushing its own militaristic security road map of the Greater Middle East democratic initiative, justifying it as a means to retaliate and eradicate the terrorist threats towards themselves. However, with its five-year lopsided victories that cost the nation almost four thousand military casualties, and the war expenses that could match the Vietnam war, the U.S. does not yet seem to be totally emancipated from the fears of terrorism. Terrorism, in itself, is a means of resisting forced rules a form of alternative competition by the weak against the strong, and a way of expressing a dismissive response against dictatorial ideas or orders which allow for no normal changes. Intrinsically, the nature of terrorism is a reaction opposing power logics. Confronted with the absolute military power of the U.S., the Islamic strategies of terrorism have begun to rapidly evolve into a new stage. The new strategies take advantage of their civilization and circumstances, they train and inspire their front-line fighters on the Internet, and issue their orders through the clandestine network of the Al Qaeda operatives. These spontaneously generated strategies have been gained speed among the second, and third Islamic generations, many of whom are now spread throughout western societies. This represents a failure of the power-driven, one-sided overseas security initiatives by the U.S., and is creating a culture of fear and distrust in western societies. It is feared that the U.S. war campaigns have made the clash of religions far worse than before, and may ever lead to global ethnic separations and large-scale population movements. Eventually, it may result in the terrorist groups, enlarged and secretly supported by the huge sums of oil money, driving all mankind into a series of irreparable catastrophes.

• Childhood Kidney Diseases
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• v.11 no.2
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• pp.178-184
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• 2007

Purpose : Since the first report by Mendoza in 1990, there have been several studies reporting that long-term intravenous methylprednisolone(MP) pulse therapy combined with cyclosporin A(CsA) or cyclophosphamide might be beneficial for the treatment of steroid resistant focal segmental glometulosclerosis(FSGS). We investigated the therapeutic effect of long-term MP pulse therapy without CsA or cyclophosphamide on steroid resistant FSGS. Methods : The medical records of the 10 steroid resistant FSGS patients who were treated with MP pulse therapy by the Mendoza protocol without CsA or cyclophosphamide in our hospital were retrospectively reviewed. Results : The median age at onset was 2.6 years(range 1.1-10.6 years) and the median age at the initiation of therapy was 5.7 years(range 1.8-20 years). The median duration of follow-up was 35 months(range 4-132 months). At the end of therapy, 5 patients achieved complete remission(50%) and 2 partial remission(20%), one of whom relapsed after the therapy. Three patients did not respond to the therapy, two of whom progressed to end-stage renal failure during the therapy eventually requiring kidney transplantation. Conclusion : Intravenous long-term MP pulse therapy without CsA or cyclophosphamide by the Mendoza protocol may be effective in a subset of patients with steroid-resistant FSGS.

• Journal of Chest Surgery
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• v.29 no.6
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• pp.606-613
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• 1996

Cardiac transplantation has been the treatment of patients with end-stage heart disease since it was first performed in 1967. In Korea the first case was performed in 1992 and 42 patients underwent heart trans- plantation so far. The purpose of this article is to report short-term result of cardiac transplantation at our center. Between April 1994 and September 1995, 14 patients had undergone orthotopic heart transplantations. There was 12 male and 2 female patients. Mea recipient age was 34 years(range 11 to 54 years) and mean donor age was 28.4 years(16 to 50 years). Mean graft ischemic time was 120.7minutes(80 to 280 minutes). The follow-up period after transplantation was 11 months(3 to 17 months). Recipient diagnosis included dilated cardiomyopathy in 10, ischemic cardiomyopathy in 2, valvular cardiomyopathy in 1, congenital complex heart disease in 1 patient. The preoperative status of the recipients were state I (50%) and ll (50%) by UNOS classification and class 111 (5 patients) and class IV (9) by NYHA functional class. All patients were treated with triple-drug immunosuppression (cyclosporine, azathioprine, steroid) and induction with RATG. The rejection episodes were 5 times in 3 patients during the follow-up. Causes of infection were aspergillosis (2), and hepes zoster (1), CMV pneumonitis (1). Permanent pace- maker was inserted in 1 patient. Currently 9 patients are alive with seven patients in WYHA functional class I and two in class l . The ejection fraction increased from preoperative value of 19.9 $\pm$ 3.4% to postoperative value of 69.0 $\pm$ 5.6%. The causes of death were cellular rejection (1),chronic graft failure due to size-mismatching (1),respirat- oxy insufficiency due to asthma attack (1), subarachnoid hemorrhage (1), and RIO humoral rejection (1).

• Journal of Intelligence and Information Systems
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• v.28 no.1
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• pp.89-106
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• 2022

Recently, the amount of video data collected from smartphones, CCTVs, black boxes, and high-definition cameras has increased rapidly. According to the increasing video data, the requirements for analysis and utilization are increasing. Due to the lack of skilled manpower to analyze videos in many industries, machine learning and artificial intelligence are actively used to assist manpower. In this situation, the demand for various computer vision technologies such as object detection and tracking, action detection, emotion detection, and Re-ID also increased rapidly. However, the object detection and tracking technology has many difficulties that degrade performance, such as re-appearance after the object's departure from the video recording location, and occlusion. Accordingly, action and emotion detection models based on object detection and tracking models also have difficulties in extracting data for each object. In addition, deep learning architectures consist of various models suffer from performance degradation due to bottlenects and lack of optimization. In this study, we propose an video analysis system consists of YOLOv5 based DeepSORT object tracking model, SlowFast based action recognition model, Torchreid based Re-ID model, and AWS Rekognition which is emotion recognition service. Proposed model uses single-linkage hierarchical clustering based Re-ID and some processing method which maximize hardware throughput. It has higher accuracy than the performance of the re-identification model using simple metrics, near real-time processing performance, and prevents tracking failure due to object departure and re-emergence, occlusion, etc. By continuously linking the action and facial emotion detection results of each object to the same object, it is possible to efficiently analyze videos. The re-identification model extracts a feature vector from the bounding box of object image detected by the object tracking model for each frame, and applies the single-linkage hierarchical clustering from the past frame using the extracted feature vectors to identify the same object that failed to track. Through the above process, it is possible to re-track the same object that has failed to tracking in the case of re-appearance or occlusion after leaving the video location. As a result, action and facial emotion detection results of the newly recognized object due to the tracking fails can be linked to those of the object that appeared in the past. On the other hand, as a way to improve processing performance, we introduce Bounding Box Queue by Object and Feature Queue method that can reduce RAM memory requirements while maximizing GPU memory throughput. Also we introduce the IoF(Intersection over Face) algorithm that allows facial emotion recognized through AWS Rekognition to be linked with object tracking information. The academic significance of this study is that the two-stage re-identification model can have real-time performance even in a high-cost environment that performs action and facial emotion detection according to processing techniques without reducing the accuracy by using simple metrics to achieve real-time performance. The practical implication of this study is that in various industrial fields that require action and facial emotion detection but have many difficulties due to the fails in object tracking can analyze videos effectively through proposed model. Proposed model which has high accuracy of retrace and processing performance can be used in various fields such as intelligent monitoring, observation services and behavioral or psychological analysis services where the integration of tracking information and extracted metadata creates greate industrial and business value. In the future, in order to measure the object tracking performance more precisely, there is a need to conduct an experiment using the MOT Challenge dataset, which is data used by many international conferences. We will investigate the problem that the IoF algorithm cannot solve to develop an additional complementary algorithm. In addition, we plan to conduct additional research to apply this model to various fields' dataset related to intelligent video analysis.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.18 no.1
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• pp.253-270
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• 2023

Research on investment determinants of accelerators, which are attracting attention by greatly improving the survival rate of startups by providing professional incubation and investment to startups at the same time, is gradually expanding. However, previous studies do not have a theoretical basis in developing investment determinants in the early stages, and they use factors of angel investors or venture capital, which are similar investors, and are still in the stage of analyzing importance and priority through empirical research. Therefore, this study verified for the first time in Korea the discrimination and effectiveness of investment determinants using accelerator investment determinants developed based on the business model innovation framework in previous studies. To this end, we first set the criteria for success and failure of startup investment based on scale-up theory and conducted a survey of 22 investment experts from 14 accelerators in Korea, and secured valid data on a total of 97 startups, including 52 successful scale-up startups and 45 failed scale-up startups, were obtained and an independent sample t-test was conducted to verify the mean difference between these two groups by accelerator investment determinants. As a result of the analysis, it was confirmed that the investment determinants of accelerators based on business model innovation framework have considerable discrimination in finding successful startups and making investment decisions. In addition, as a result of analyzing manufacturing-related startups and service-related startups considering the characteristics of innovation by industry, manufacturing-related startups differed in business model, strategy, and dynamic capability factors, while service-related startups differed in dynamic capabilities. This study has great academic implications in that it verified the practical effectiveness of accelerator investment determinants derived based on business model innovation framework for the first time in Korea, and it has high practical value in that it can make effective investments by providing theoretical grounds and detailed information for investment decisions.

• Radiation Oncology Journal
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• v.21 no.4
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• pp.261-268
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• 2003

Purpose: To report the results of curative treatment for patients with tonsil cancer by retrospective analysis. Materials and Methods: From Jan. 1995 till Dec. 2000, 27 patients with squamous cell carcinoma of the tonsil received curative treatment at Samsung Medical Center. Therapeutic decision was made through multidisciplinary conference, and curative radiation therapy was favored when, (1) the patient's condition was not fit for general anesthesia and surgery, (2) the patient refused surgery, (3) complete resection was presumed impossible, or (4) too severe disability was expected after surgery. Surgery was the main local modality in 17 patients (S$\pm$RT group), and radiation therapy in 10 (RT$\pm$CT group). The median follow-up period was 41 months. Results: AJCC stages were I/II in four, III in two, and IV in 21 patients. The 5-year disease-free survival rate was 73.3$\%$ in all patients, 70.6$\%$ in the S$\pm$RT group, and 77.8$\%$ in the RT$\pm$CT group. Treatment failure occurred in seven patients, all with stage III/IV, and all the failures occurred within 24 months of the start of treatment. Five patients among the S$\pm$CT group developed treatment failures; 2 local, 2 regional, and 1 distant (crude rate=29.4$\%$). Two patients among the RT$\pm$CT group developed failures; 1 synchronous local and regional, and 1 distant (crude rate=20.0$\%$). The 5-year overall survival rate was 77.0$\%$ in all patients, 80.9$\%$ in the S$\pm$RT group, and 70.0$\%$ in the RT$\pm$CT group. Conclusion: We could achieve favorable results that were comparable to previously reported data with respect to both the rates of local control and of survival by applying S$\pm$RT and RT$\pm$CT. RT$\pm$CT is judged to be an alternative option that can avoid the functional disability after surgical resection.

• Journal of Chest Surgery
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• v.41 no.2
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• pp.202-209
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• 2008

Background: The introduction of Drug Eluting Stents (DES) decreased the number of patients referred for coronary artery bypass grafting (CABG). The impact of DES on CABG (Step 1) was studied and compared with the 1-year outcome after CABG with DES (Step 2). Material and Method: Surgical results for patients who underwent off-pump CABG (OPCAB) before the introduction of DES(n=298) were compared with those who underwent OPCAB after the introduction of DES (n=288) (Step 1). Postoperative 30-day and 1-year results were also compared between the patients who underwent percutaneous coronary intervention (PCI) using DES (n=220) and those who underwent OPCAB (n=255) (Step 2). Result: Since the introduction of DES, the ratio of CABG versus PCI decreased. In the CABG group, the number of high risk patients such as elderly patients (age 62 vs. 64, p=0.023), those with chronic renal failure (4% vs. 9%, p=0.021), calcification of the ascending aorta (9% vs. 15%, p=0.043), or frequency of urgent or emergent operations (12% vs. 22%, p=0.002) increased. However, there were no differences in the cardiac death and graft patency rates between the two groups (step 1). During the one-year follow up period, the rate of target vessel revascularization (12.3% vs. 2.4%, p<0.001) and major adverse cardiac events (MACE: death, myocardial infarct, TVR) were higher in the DES than the CABG group (13.6% vs 4.3%) (stage 2). Conclusion: Introduction of DES decreased the number of patients referred for surgery, and increased the comorbidity in patients who underwent CABG. DES increased the rate of target vessel revascularization, and the occurrence of MACE during the 1-year follow-up. However, there was no difference in the incidence of myocardial infarction and cardiac death between the two groups.

• Radiation Oncology Journal
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• v.20 no.2
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• pp.139-146
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• 2002

Purpose : This study evaluated the treatment outcomes, patterns of failure, and treatment related complications of primary lymphoma patients who received definitive radiation therapy. Materials and Methods : A retrospective analysis was undertaken for 31 patients with primary orbital lymphoma at the Asan Medical Center between February 1991 and April 2001. There were 18 males and 13 females with ages ranging from 3 to 73 years (median, 44 years). The involved sites were 9 conjunctivae, 12 eyelids and 10 other orbits. The histological types were 28 MALT lymphomas (low-grade B-cell lymphoma of mucosa-associated lymphoid tissue type), 1 diffuse large B-cell lymphoma, 1 anaplastic large cell lymphoma and 1 lymphoblastic lymphoma. The Ann Arbor stages were all IE $(100\%)$. Ann Arbor stage III or IV patients were excluded from this study, Bilateral orbital involvement occurred in 6 cases. Radiation therapy was given with one anterior port of high energy electrons $(6\~16\;MeV)$ for the lesions located at the anterior structures like the conjunctivae or eyelids. Lesions with a posterior extension or other orbital lesions were treated with 4 or 6 MeV photons with appropriately arranged portals. In particular, lens blocks composed of lead alloy were used in conjunctival or eyelid lesions. Twelve patients received chemotherapy. The median follow-up period was 53 months. Results : The 5-year overall, cause-specific, and disease-free survival was $91\%,\;96\%,\;and\;80\%$, respectively. The complete response rate 6 months after radiation therapy was $100\%$. Local recurrences were observed in 2 patients at 16 and 18 months after completion of radiation treatment. They were salvaged with additional radiation therapy. Two patients developed distant metastases. A MALT lymphoma patient with a lung relapse was successfully salvaged with radiotherapy, but the other lymphoblastic lymphoma patient with bone marrow relapse expired. There were no severe complications but 5 patients developed radiation-induced cataracts and 2 patients developed dry eye. Conclusion : Most primary orbital lymphomas consisted of MALT lymphomas. Radiation therapy was a successful treatment modality for orbital lymphoma without any severe complications. In cases of local relapses, radiation therapy is also a very successful salvage treatment modality.