PVD 적용지반에서 단계성토시 침하량 예측

강성현(Seong-Hyeon Kang),김태형(Tae-Hyung Kim) 한국지반신소재학회 2014 한국토목섬유학회 학술발표회 Vol.2014 No.11

Settlement prediction has been conducted using Hyperbolic, Hoshino, and Monden methods, etc in the fields. These methods are only able to predict settlement after finishing the final filling stage. A new method is proposed to make up for such a weak point. This method was named as Kang"s method, which can be able to predict the settlement both the final filling stage and the staged filling from the initial filling stage in soft ground. To verify the applicability of this method, the measured settlement curve history was compared with the predicted one. The predicted settlement is well matched with the measured one. From the study, the Kang"s method can be possible to predict settlement during the staged filling with only the initial settlement data.

블록 암호화를 위한 Blowfish 구현

성해경,박종태,노진수,이강현 조선대학교 에너지.자원신기술연구소 2002 에너지·자원신기술연구소 논문지 Vol.24 No.2

Blowfish is a symmetric block cipher that can be used as a drop-in replacement for DES or IDEA. It takes a variable-length key, from 32bits to 448bits, making it ideal for both domestic and exportable use. In this paper, the Blowfish unit is designed using pipeline architecture and correctly implements the algorithm with a focus on ease-of-design and ease-of-use without sacrificing too much speed or size. For the real time process of Blowfish, it is required that high-speed operation and small size hardware. So, the scheme of new adders designed has all advantages abstracted from other adders. As a result of this new adder designed, area cost increases by 1.05 times but the operation speed increases by 1.2 times.

학생들이 사용한 엔진 구동형 Ni-Ti file systems의 근관 성형 효율 비교

강문성,김현철,허복,박정길 大韓齒科保存學會 2006 Restorative Dentistry & Endodontics Vol.31 No.1

본 연구의 목적은 학생들이 사용한 세 가지 Ni-Ti 파일의 성형효율을 비교하고, 각 파일의 사용 경험 유무에 따른 차이를 비교하여 치과대학생을 위한 교육에 적합한 종류를 선택하는데 도움을 얻고자하는 것이다. Ni-Ti 파일 사용 경험이 없는 학생 50명과 Ni-Ti 파일을 사용한 근관치료 경력이 2년 이상인 경험자 10명이 세 종류의 Ni-Ti file - ProFile^(®) (PF), HeroShaper^(®) (HS), K3™ (K3) -을 사용하여 180개의 근관 모형을 성형하였다. 근관성형 시간 및 기구 변형, 근관 이형성을 조사하고 성형 전후 상을 중첩하여 근관 삭제폭, 근관변위량과 중심변위율을 1, 3, 5 ㎜에서 분석하였다. 1. 근관 성형시간은 HS군이 가장 빨랐으며, 총 삭제량은 모든 지점에서 K3군이 다른 군보다 컸다 (P<0.05). 2. 세 군 모두 1, 3 ㎜에서 외측 변이를 보였고, 1 ㎜ 지점에서 PF군이 가장 안정적이었다 (P< 0.05). 3. 중심변위율은 1, 3 ㎜에서 HS, PF군이 K3군보다 작았다. 5 ㎜ 지점에서 PF군이 가장 작았고, PF군 3 ㎜에서 학생은 경험자보다 유의하게 작았다 (P < 0.05). The purpose of this study was to compare the shaping ability of three Ni-Ti file systems used by dental students or the experts and consequently to aid in choosing a proper systems for educational courses of dental students and beginners. Fifty students and ten dentists who have clinical experience over two years prepared 180 simulated root canals in resin blocks with three Ni-Ti systems: ProFile^(®) (PF), HeroShaper^(®) (HS), K3™ (K3). After preparation, the Ni-Ti files were evaluated for distortion and canal preparation time was recorded. The images of pre- and post-instrumented canals were scanned and superimposed. Amounts of increased canal widths,deviation, and centering ratio were calculated at apical 1, 3 and 5 ㎜ levels and statistical analysis was performed. The results were as follows: 1. HS showed the shortest preparation time and instrumented canal width in K3 was significantly larger than other groups (P< 0.05). 2. At 1 and 3 ㎜ levels, all groups had outward deviation. In student group, at the 1 ㎜ level, PF had the least deviation (P< 0.05). 3. In the centering ratio, the PF had the best centering ability compared to the others at 5 ㎜ level. At 1 and 3 ㎜ level, HS and PF had better abilities than K3. Student group had better ratio than the expert at 3 ㎜ level with PF (P<0.05). Based on the results, it is surmised that the ProFile^(®) is the safest and most ideal instrument for students and beginners.〔J Kor Acad Cons Dent 31(1):1-10, 2006〕

8비트 RISC 프로세서 설계

성해경,이강현 조선대학교 에너지.자원신기술연구소 2003 에너지·자원신기술연구소 논문지 Vol.25 No.1

An importance about the complicated function and the operation speed of arithmetic is rising its head on the info-communication society which has rapidly development. Currently, 8bit RISC processor is used widely in the info-communication systems. Also, the core library of RISC processor can be applied easily in embedded system. So it requires more complicated function and the fast operation speed of arithmetic to all systems. In this paper, the authors designed 8bit RISC processor for high speed operation core that is able to applying the embedded system. The design specification proposed has 15 instructions, and we confirmed that Vdd is 3.3V when clock frequency is 50㎒.

원발성 폐암 환자의 생존율에 관한 보고

김현태,이상무,어수택,박춘식,정성환,허승재,남충희,강창희,김용훈 순천향대학교 1994 논문집 Vol.17 No.4

We analysed 404 patients with primary lung carcinoma who were treated at Soonchunhyang University Hospital from July, 1985 to september, 1993 in order to investigate the survival rate and epidemiolgical properties of primary lung cancer. They were 330 males and 74 females. The most prevalent decade was seventh. In terms of cell type, the squamous cell was 225 patients (55%), and adenocarcinoma, small cell, mixed type was 21%, 19%, 4%, respectively. Among non-small cell lung carcinoma, stage Ⅲa was the most prevalent one(92%). In case of small cell carcinoma, the limited stage was 64%. The 12-, 24-, 36- month survival rate of total patients was 57%, 31%, 22%, respectivley and median sruvival time was 15 months. The 36-month survival rate tended to be longer in non-small cell lung carcinoma than that of small cell lung cancer, but there was no difference between two groups, statistically. In non-small cell carcinoma, The 36-month survival rate and meidan survival time were longer in the stage Ⅰ and Ⅱ than those of Ⅲa, Ⅲb, Ⅳ (80% versus 38%, 22%, 0%, p<0.05). According to involvement of lymph node, the 36-month survival rate was longer in NO and N1 than those of N2, N3 (61.9%, 48.7% versus 17.7%, 17.3%, p<0.05). In small cell carcinoma, The 36-month survival rate and median survival rate were higher and longer in limited stage than those of extensive stage(16.1% and 13 month vs 10% and 8 month, p<0.05). In conclusion, we report here the incidence of primary lung carcinoma and the survival rate of paients with primary lung carcinoma who were treated in Soonchunhyang University Hospital.

혈액 투석 환자에서 중심정맥 협착에 대한 스텐트 삽입술 : Wallstent Placement

임대승,노상필,이유선,정승현,김보영,이정우,강정아,김정희,이민수,정준용,최시완,정진옥,성인환,이강욱,신영태 충남대학교 의과대학 의학연구소 2002 충남의대잡지 Vol.29 No.1

Stenosis of central vein is a common complication arising after percutaneous subclavian vein catheter insertion performed for temporary vascular access in chronic renal failure patients undergoing hemodialysis. There are several treatment methods for the condition like percutaneous angioplasty(PTA), stent insertion, and surgery, but recent trend is toward PTA and stents. Among the patients diagnosed with chronic renal failure from March 1993 to May 2002 and undergoing hemodialysis through AV fistula, the 14 Patients in whom central vein stenosis arose were selected for the study. A total of 28 percutaneous interventions(5 PTA and 23 stent placement) were performed, and restenosis rate and the time taken till the restenosis in de novo lesions and instant lesions were compared. All 28 cases were operated successfully. The 14 cases that received both anigioplasty and stent placement initially. (de novo lesion : 14 cases), Among the 10 cases with de novo lesion that followed up more than 1 year, 3 cases are currently undergoing hemodialysis without restenosis, and the remaining 7 cases have recurred stenosis with the mean time to restenosis of 10.9 months. In the 7 cases in whom stenosis recurred, 11 interventions were done(instent lesion: 11 cases). 4 of these were using only ballon angioplasty with 100% restenosis rate and the mean time of 3 months until restenosis. The remaining 7 cases were using both balloon angioplasty and stent placement, also with 100% restenosis rate but with the mean time of 12 months until restenosis, which was later than the group receiving only balloon angioplasty. In treating the patients with central vein stenosis, stent placement seems to be more advantageous over PTA in terms of restenosis rate and the mean duration of patency. In the case of instent lesion, inserting the stent for the second time after stenosis recurred lengthened the duration of patency compared to performing balloon angioplasty alone.

A Monte Carlo simulation study for feasibility of total variation (TV) noise reduction technique using digital mouse whole body (MOBY) phantom image

Kang, Seong-Hyeon,Kim, Ka Yeon,Hwang, Yoonji,Hong, Ji Woo,Baek, So Rim,Lee, Chang-Lae,Lee, Youngjin Elsevier 2018 Optik Vol.156 No.-

<P><B>Abstract</B></P> <P>Although radiation dose based on X-ray source is becoming a concern, use of micro-computed tomography (m-CT) system continues to grow in diagnostic imaging. To address radiation dose concern in m-CT system, Monte Carlo simulation using Geant4 Application for Tomography Emission (GATE) tool and noise reduction technique have recently developed. Among these techniques, total variation (TV) noise reduction technique is well known to many researchers for X-ray imaging. Also, an important disadvantage of median filter and Wiener filter is low edge preservation compared with recently developed noise reduction methods Thus, the aim of this study was to design TV noise reduction technique based on L1-norm estimation with iterative method and compare to other techniques in m-CT system using GATE simulation. We used 4-dimension (4D) digital mouse whole body (MOBY) phantom and to clarify the feasibility of TV noise reduction technique in m-CT images, we compared the image performance using contrast-to-noise ratio (CNR) and coefficient of variation (COV). According to the results, the average for three image planes (coronal, sagittal and transverse) of CNR and COV of the TV noise reduction technique were 68.07 and 1.61%, respectively. In particular, the CNR and the COV difference between TV noise reduction technique and noisy image were maximum 5.28 and 2.89 times, respectively. In conclusion, the results of this study suggested that TV noise reduction technique can be achieved improved performance and the effect and feasibility of TV noise reduction technique for m-CT imaging can be investigated.</P>

Impact on Four-dimensional Dose Accumulation Using Deformable Image registration in Liver Stereotactic Body Radiotherapy

Seong-Hee Kang,Tae-Ho Kim,Dong-Su Kim,Cheon-Keum Seong,Min-Seok Cho,Kyeong-Hyeon Kim,So-Hyun Park,Siyong Kim,Tae Suk Suh 대한방사선방어학회 2014 대한방사선방어학회 학술발표회 논문요약집 Vol.2014 No.11

Fast non-local means approach noise reduction in mouse light microscopic image using separable color channels

Seong-Hyeon Kang,Ji-Youn Kim 한국실험동물학회 2023 한국실험동물학회 학술발표대회 논문집 Vol.2023 No.2

Quantitative evaluation of total variation noise reduction algorithm in CT images using 3D-printed customized phantom for femur diagnosis

Kang Seong-Hyeon,Park Minji,Yoon Myeong Seong,Lee Youngjin 한국물리학회 2022 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.81 No.5

The purpose of this study was to evaluate the usefulness of the total variation (TV) noise reduction algorithm for improving image characteristics with 3D printing technique for the accuracy enhancement of femur fracture diagnosis with computed tomography (CT) images. For this purpose, 3D printing technique was applied to output customized phantom, which can copy a human femur, with iron-polylactic acid flaments that has similar density of human bones. Then, CT images of 3D printed customized femur phantom were obtained by applying the conditions for tube current of 100 mA, 200 mA, and 400 mA, respectively. In addition, a TV noise reduction algorithm applied with regularization parameters of 0.005 and 0.05, respectively, was modeled and applied to 100 mA CT images. To quantitative evaluate the degree of improvement for TV noise reduction algorithm, coefcient of variation (CV) and contrast to noise ratio (CNR), which are noise level evaluation parameters, and blind/referenceless image spatial quality evaluator (BRISQUE) and natural image quality evaluator (NIQE), which are no-reference image quality assessment, were calculated. As a result, when the TV noise reduction algorithms with regularization parameters of 0.005 and 0.05 were applied to the 100 mA image, the noise level evaluation parameters showed similar or improved to the 200 mA and 400 mA images, respectively. On the other hand, the BRISQUE was most improved when the TV noise reduction algorithm with regularization parameters of 0.005 was applied, however, the 0.05 showed poorer results than the images without algorithm. In addition, the NIQE showed that when the TV noise reduction algorithm was applied, the results were improved compared to the CT images without the algorithm, and the regularization parameter of 0.005 was improved than 0.05. In conclusion, we demonstrated through experiment with 3D printing technique that TV noise reduction algorithm with an appropriate regularization parameter can solve the problem of noise and artifacts in the femur CT images.