• Proceedings of the Korea Multimedia Society Conference
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• 2003.11a
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• pp.158-161
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• 2003

1985년 N. Koblitz와 V. Miller가 각각 독립적으로 제안한 타원곡선 암호시스템(ECC : Elliptic Curve Cryptosystems)은 유한체 위에서 정의된 타원곡선 군에서의 이산대수 어려움에 기초한다. 타원곡선 암호시스템은 다른 공개키 시스템에 비해 보다 짧은 길이의 키만으로도 동일한 수준의 안전도를 유지할 수 있다는 장점으로 인하여, 스마트카드나 모바일 시스템 등에서와 같이 메모리와 처리능력이 제한된 하드웨어에도 이식 가능한 장점이 있다. 본 논문에서는 타원곡선 암호시스템에 필요한 유한체 연산을 이진체(Binary Finite Field)인 GF(2$^{193}$ )과 OEF(Oprimal Extension Field) 상에서 VHDL 언어를 사용하여 구현을 하였고 각 연산의 성능을 비교하였다.

• Annual Conference on Human and Language Technology
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• 1999.10e
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• pp.382-388
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• 1999

이 논문은 두 가지 목적을 가진다. 첫째, 대명사의 선행사 탐색을 위한 이론으로 널리 알려진 중심화이론을 필자들이 수정확대한 통제된 중심화 이론(Controlled Centering Theory, 이하 CCT)을 소개한다. 둘째, 한국어의 대화에서 나타나는 대명사의 선행사 탐색문제에 대한 설명력있는 해답을 CCT의 틀안에서 제시한다. 이를 위해 제한된 영역 대화라 할 수 있는 호텔예약대화에 나타나는 영대명사의 특성에 대해 논의하고, 그 선행사 탐색과 관련하여, 정보구조적인 관점에서 슬롯연결성분이 영대명사의 선행사일 가능성이 높기 때문에 중심화이론의 주요 구성요소인 전향적 중심리스트 서열의 최상위에 슬롯성분이 위치해야 한다는 논지를 전개한다. 어떤 영대명사의 선행사가 될 수 있는 후보자가 여럿일 경우에 가장 적합한 선행사를 찾아내기 위해서는 별도로 '개념양립성제약을' 설정할 필요가 있다고 주장한다 광역대화에 나타나는 명시적인 대명사의 선행사 탐색과 관련하여서는 대명사의 선행사는 대명사를 담화통어할 수 있는 위치에 있어야 한다는 담화통어제약을 제안하고, 담화통어 개념을 정의한다.

• Tuberculosis and Respiratory Diseases
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• v.51 no.1
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• pp.17-24
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• 2001

Background : Community-acquired pneumonia(CAP) remains a leading cause of morbidity and mortality worldwide. Recently, the evolution of drug-resistant microorganisms has become a serious problem in CAP management. Specific antimicrobial therapy is the cornerstone of CAP management. However, obtaining an accurate etiologic diagnosis clinically is not easy and empirical antimicrobial treatment is usually administered prior to the correct microbiologic diagnosis. In this study, the clinical usefulness of empirical CAP treatment was investigated. Methods : A total 35 cases were studied prospectively over a 16-month period in Mokpo Catholic Hospital from Dec. 1995 to Mar. 1997. The microbiologic diagnosis was made by sputum, blood culture, a specific serum antibody test and an immunologic study. Results : The causative organisms were isolated in 10 (30%) out of 33 cases: 8 cases and 1 case on the sputum culture and blood culture respectively, and 1 case by an indirect hemagglutinin test. 12 cases had underlying diseases: pulmonary tuberculosis 4, alcoholism 4, diabetes mellitus 3, and liver cirrhosis 1. Antimicrobial treatment was given empirically and all cases recovered. Conclusion : A definite microbiologic diagnosis before commencing the appropriate treatment in CAP is not straightforward. Empirical therapy according to a clinical assessment is important and helpful. However, every effort to make the correct etiologic diagnosis should be taken.

• Clinical and Experimental Pediatrics
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• v.45 no.4
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• pp.489-497
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• 2002

Purpose : The objectives of this study were to investigate the causes of chronic cough and to establish the appropriate diagnostic approach to chronic cough in children. Methods : One hundred and thirty two cases of chronic cough were prospectively evaluated. They visitors to pediatric chronic cough clinics at Kang-nam saint Mary's Hospital of Catholic University from August 2000 to July 2001 for 12 months. Careful history taking by questionnaire, physical examination, radiologic studies of chest and sinus, hematologic and immunologic studies, allergic skin tests, and methacholine challenge tests were performed. Color doppler(CD) ultrasonography were performed and compared with simultaneous 24 Hr. esophageal pH monitoring to diagnose gastroesophageal reflux disease(GERD). Results : Age distributions were demonstrated that nine in infants, 82 in early childhood, 38 in late childhood, and three in adolescence. Common causes of chronic cough were bronchial asthma in 40 cases, chronic sinusitis in 22 cases, GERD in seven cases, bronchial asthma combined with sinusitis in 28 cases, bronchial asthma combined with GERD in 14 cases, psychogenic cough in two. cases, foreign body in one case, chronic bronchitis in one case, and bronchiolitis in one case. Comparing with 24 Hr. pH monitoring, sensitivity, specificity, positive predictive value and negative predictive values of CD ultrasonography were 88%, 69%, 85 %, and 73% respectively. Conclusion : The most common causes of chronic cough in children were bronchial asthma, sinusitis and GERD in order. We suggest that CD ultrasonography can be used as a good, convenient screening method for patients with suspected GERD in outpatient settings.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.1
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• pp.98-102
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• 1997

The antiulcerative effect of Sikhe(Korean traditional sweet rice drink) on stomach ulcer induced by ethanol treatment was investigated. Fifty male mice were divided into 5 groups consisting of control group and 4 Sikhe groups fed 0.3% commercial Sikhe(group I), 3% commercial Sikhe(group II), 0.3% home-made Sikhe(group III) and 3% home-made Sikhe(group IV). Mice were fed experimental diet ad libitum for 45 days. Growth, stomach surface pH, gastric wall mucosa and ulcer index were examined. Feed intake and weight gain did not show significant differences among 5 groups(p>0.05). The stomach surface pH and the amount of gastric wall mucosa of Sikhe fed groups(group I~IV) were higher than those of the control group, but were not significantly different(p>0.05) . The ulcer indices of the control and Sikhe fed groups were 18.6$\pm$6.58mm and 13.7$\pm$5.87~17.8$\pm$9.10, respectively. But significant differences were not found between the control and the Sikhe fed groups(p>0.05) though mean values of Sikhe fed groups were lower than that of the control group.

• Journal of Gastric Cancer
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• v.8 no.4
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• pp.225-231
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• 2008

Purpose: Laparoscopic gastric resection (LGR) is increasingly being used instead of open gastric resection (OGR) as the standard surgical treatment for gastric submucosal tumors. Yet there are few reports on which technique shows better postoperative outcomes. This study was performed to compare these two treatment modalities for gastric submucosal tumors by evaluating the postoperative outcomes. We also provide an analysis of the learning curve for LGR. Materials and Methods: Between 2003.4 and 2008.8, 103 patients with a gastric submucosal tumor underwent either LGR (N=78) or OGR (n=25). A retrospective review was performed on a prospectively obtained database of 103 patients. We reviewed the data with regard to the operative time, the blood loss during the operation, the time to the first soft diet, the postoperative hospital stay, the tumor size and the tumor location. Results: The clinicopatholgic and tumor characteristics of the patients were similar for both groups. There was no open conversion in the LGR group. The mean operation time and the bleeding loss were not different between the LGR group and the OWR group. The time to first soft diet (3.27 vs. 6.16 days, P<0.001) and the length of the postoperative hospital stay (7.37 vs. 8.88 days, P=0.002) were shorter in the LGR group compared to the OGR group. The tumor size was bigger in the OGR group than that in the LGR group (6.44 vs. 3.65 cm, P<0.001). When performing laparoscopic gastric resection of gastric SMT, the surgeon was able to decrease the operation time and bleeding loss with gaining more experience. We separated the total cases into 3 periods to compare the operation time, the bleeding losses and the complications. The third period showed the shortest operation time, the least bleeding loss and the fewest complications. Conclusion: LGR for treating a gastric submucosal tumor was superior to OGR in terms of the postoperative outcomes. An operator needs some experience to perform a complete laparoscopic gastric resection. Laparoscopic resection could be considered the first-line treatment for gastric submucosal tumors.

• Journal of the Korean Arthroscopy Society
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• v.15 no.1
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• pp.1-6
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• 2011

Purpose: The purpose of this prospective study is to compare the results of arthroscopic reconstruction of ACL using autologous hamstring tendon (Group 1) and autologous bone patella tendon bone (Group 2). Materials and Methods: From Jan. 2004 to Dec. 2007, fifty patients were analyzed in this study. A single surgeon performed the ACL reconstruction with autologous hamstring tendon (25 patients) and autologous bone patella tendon bone (25 patients) alternatively each other. The mean follow up period of two groups was 38 months (range 25~58 months). We evaluated the result of Lachman test, Pivot shift test as a physical examination and Lysholm score, Tagner activity scale as patients' satisfaction and functional status and Telometer for anterior instability of each groups at the time of final follow up. Results: In final results, negative or mild positive findings on Lachman test were 24 out of 25 cases (equally) in each groups.) Twenty two cases in the Group 1 and 21 cases in the Group 2 were negative on Pivot shift test. Lysholm scores mark 94.6 points in group 1 and 92.3 points in group 2 at the final follow up and Tegner activity scales mark 8.5 points (Group 1) and 8.1 points (Group 2) at the time of last follow up and there were no differences between the two groups statistically. The numbers of patients who have less than 5 mm of anterior translation of tibia under telometer at 20 degrees of knee flexion are 24 cases in group 1 and 23 cases in group 2. Conclusion: The overall improvements of clinical scores (Lysholm scores and Tegner Activity scales) of the group 1 were a little bit superior to those of the group 2, but there were no significant statistical difference between two groups.

• Journal of Gastric Cancer
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• v.7 no.4
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• pp.206-212
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• 2007

Purpose: The number of laparoscopy assisted distal gastrectomies (LADG) is gradually increasing for the treatment of early gastric cancer (EGC) patients as a surgical modality for improving quality of life. However, there are few reports on laparoscopy-assisted total gastrectomy (LATG), mainly because this procedure is performed relatively infrequently, and the procedure is more complicated than LADG. This study was performed to evaluate the technical feasibility, safety, and surgical results of LATG with lymphadenectomy through a review of our experience. Materials and Methods: From July 2003 to June 2007, 77 LATG with Roux-en-Y esophagojejunostomy were performed for patients with a preoperative diagnosis of EGC. The clinicopathological features and surgical outcomes were analyzed. Results: There were 49 males and 28 females in the study with a mean age of 61 years (range $30{\sim}85$ years). The mean operation time was 210 minutes (range $100{\sim}400$ minutes) and the operation time was gradually decreased as the case numbers increased. There were 13 operative morbidities (16.9%) and no operative mortalities. The restoration of bowel motility was noted at 3.2 postoperative days; a soft diet was started at 4.4 postoperative days and the duration of hospital stay was 10 days. There were 20 mucosal lesions, 32 submucosal lesions, 15 proper muscle lesions, 7 subserosal lesions and 3 serosal lesions. A total of 20 patients were treated by D2 lymph node dissection, 55 patients were treated by D1+$\beta$ lymph node dissection, and two patients were treated by D1+$\alpha$ lymph node dissection. The mean number of retrieved lymph nodes was 42 (range $11{\sim}86$). Lymph node metastases were noted in 12 patients. Conclusion: This study indicated LATG could be applied safely and effectively for patients with EGC. However, a prospective study comparing laparoscopy-assisted versus open gastrectomy for short-term and long-term surgical outcome is needed.

• Journal of Gastric Cancer
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• v.5 no.3 s.19
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• pp.139-145
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• 2005

Gastric cancer is the most prevalent cancer in Korea and comprises the second cause of cancer death. Surgery only can provide chance of cure, but most locally advanced cancers recur after a curative resection, even though important advances in the surgical and nonsurgical treatments of gastric cancer have taken place. Preoperative chemotherapy theoretically can provide the advantages of reducing the bulk of tumor, which might improve the R0 resection rate, and of treating micrometastases early. Also, preoperative chemotherapy is expected to render unresectable tumors resectable without increasing postoperative morbidity and mortality. There are many new chemo-therapeutic agents available for the treatment of advanced gastric cancer, but still the most effective agent, the optimal time and number of cycle for administration are still not known. The addition of postoperative chemotherapy through an intraperitoneal route and/or radiotherapy might affect the outcome of surgery favorably, but that hasn't been proved yet. A multicenter prospective randomized phase III trial should be peformed to answer for those questions and to improve the curability of gastric cancer treatment.

• Journal of Gastric Cancer
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• v.8 no.3
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• pp.141-147
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• 2008

Purpose: The aim of this study was to compare the short-term operative outcomes of laparoscopy-assisted total gastrectomy (LATG) with those of open total gastrectomy (OTG) for patients suffering with advanced upper gastric cancer. Materials and Methods: Of the 47 patients who underwent LATG with $D1+{\beta}$ or D2 lymphadenectomy from July 2004 to March 2008, 29 patients with pathologically proven advanced gastric cancer were compared with 35 patients who underwent conventional OTG during the same time period. The comparison was based on the clinicopathological characteristics, the surgical outcome, the follow-up survival and tumor recurrence. Results: The patients' age, gender and body mass index were similar between the two groups. However, there were statistically differences in tumor size ($9.2{\pm}3.9$ vs $6.1{\pm}3.6cm$, P=0.002) and the proximal resected margin ($2.1{\pm}2.0$ vs $3.6{\pm}2.1cm$ P=0.004). There was no significant difference in most of the peri- and post-operative courses such as the time to first flatus, the time to starting a solid diet and the length of the hospital stay, except for a longer operating time (289.0 vs. 361.3 minutes, P<0.001) in the LATG group. The complication rate was higher in the LATG group (13.8%) than that in the OTG group (5.7%). The mean overall survival and disease free survival times were 32 and 31 months, and 24 and 28 months, respectively, with an average 18.8 months follow-up duration. The main recurrent sites were peritoneum and lymph node in both groups. Conclusion: The early results of the current study suggest that LATG for AGC is technically feasible and it does not show any inferiorities of the postoperative outcomes as compared to those of conventional open total gastrectomy.