영상분할통신을 이용한 화상진료시스템의 설계

김단환,정기봉,오무송 조선대학교 전자정보통신연구소 2002 電子情報通信硏究所論文誌 Vol.5 No.2

In general cases, the conventional internet connected to a terrestrial network is transmit too large medical images. To overcome this low speed transmitting rate problem of the internet, we have studied about an image division communication system as a fast telemedicine system. The Image division communication system was 5 10 times faster than the conventional terrestrial internet link. Also, we have developed a Web-based telemedicine system that can access every permitted server of hospital via the internet. Studied image division communication corrected problem of other reflex quality decline in erratic transmission of reflex by transmission speed imbalance that is problem of single communication techniques that used in existing reflex transmission. Also, could keep quality state of fixed reflex gouge abnormal transmission speed. Visual Basic and C++, ASP programming techniques were used to make our system and it can access and retrieve medical information and image through only public web browse such as internet explorer without additional specific tools. To increase the transmitting speed of our telemedicine system, JPEG method was used. In conclusion, we were able to develop a fast and public telemedicine system using the proposed image division communication system and Web technology. Image division communication system technology increased the speed of the conventional internet and Web technology extended the scope of use for telemedicine system from intrahospital to public us.

MSE를 이용한 동영상의 장면전환검색에 관한 연구

최우진,김단환,정기봉,오무송 조선대학교 전자정보통신연구소 2002 電子情報通信硏究所論文誌 Vol.5 No.1

Multimedia information includes image information, sound information, character information and various informations. Difficulty follows to look for image which user wants by existent retrieval method. Therefore, introduce MSE(Mean Square Error) by index method for efficient practical use of video information in this research and propose scene change detection retrieval method of video. This image data for diagonal line direction color value of schedule pixel draw, (By j^(*)i matrix to Matrix A, i is frame number, j stored cost that express diagonal line Image height of frame to Matrix A). So that can grasp whole structure of video, do sampling in still image, Made user can grasp whole structure of video, do sampling in still image. Made user grasp scene change point of total video on one eye. If MSE of each frame exceeds critical value, search the frame by scene change.

7 Tesla Magnetic Resonance Image Radio-Frequency Coils for Measuring Lithium-Ion Battery Cell Performance

Dan Bi Song,Yeunchul Ryu 한국자기학회 2020 Journal of Magnetics Vol.25 No.4

In recent years, studies have been conducted to confirm the battery charge/discharge state using a magnetic resonance (MR) system. However, due to the structural characteristics of the battery, some difficulties exist in acquiring the signal. For example, because a loop coil does not coincide with the battery cell structure, non-uniform areas exist inside the cell samples, and it works as a limit to acquiring a quantitative MR signal measuring from the pack of lithium-ion batteries (LIB). In addition, the radio-frequency (RF) signals are weakened by the aluminum layer of the cell package. In this paper, we proposed a planar RF coil to obtain uniform ¹H and <SUP>7</SUP>Li signals from this shielding-packaged battery cell in 7 Tesla (T) magnetic resonance image (MRI). To demonstrate the usefulness of the proposed planar RF coil, we designed a loop coil for ¹H and <SUP>7</SUP>Li, a planar coil for ¹H, and a cut coil for ¹H and <SUP>7</SUP>Li. Then the performance of each coil was compared through a bench test. The water phantom image was acquired with each coil, and the signal intensity profile and signal-to-noise ratio (SNR) were calculated and compared. The ¹H/<SUP>7</SUP>Li images and spectra of the electrolyte phantom were obtained using the cut coils, and the results were compared with the phantom.

Alternative prosthetic vascular access creation using subscapular artery as inflow to prevent dialysis access related steal syndrome

Dan Song,Sangchul Yun 대한외과학회 2015 Annals of Surgical Treatment and Research(ASRT) Vol.88 No.6

In patients highly suspected of developing steal syndrome, the subscapular artery may be a good supplier for functional prosthetic arteriovenous access, as well as a good solution for the prevention of steal syndrome. A 51-year-old woman was preparing to have a loop shaped polytetrafluoroethylene (PTFE) graft placed at the left upper extremity. The diameter of subscapular the artery was 3 mm. Arterial calcification was not evident. The diameter of the basilic vein was 6 mm. A 50-cm long 4-7 mm tapered PTFE graft was placed in a loop shape between both skin incisions. The patient was uneventfully discharged at postoperative day 4 without any remaining steal syndrome. The PTFE graft was well-functioning during the follow-up period. The patient did not experience symptoms of steal syndrome any longer.

Posterior triangle approach for lateral in-plane technique during hemodialysis catheter insertion via the internal jugular vein

Dan Song,Sangchul Yun,Sungwoo Cho 대한외과학회 2015 Annals of Surgical Treatment and Research(ASRT) Vol.88 No.2

A recent widespread concept is that ultrasound-guided central venous catheter insertion is a mandatory method. Some techniques have been introduced for ultrasound-guided central venous catheterization. Among them, short-axis lateral in-plane technique is considered to be the most useful technique for internal jugular vein access. Therefore, we used this technique for the insertion of a large-bore cuffed tunneled dual-lumen catheter for hemodialysis. Additionally, a lesser number of catheter angulations may lead to good flow rates and catheter function; we recommend that skin puncture site in the neck at the posterior triangle is better than the Sedillot’s triangle. Using this approach, we can reduce the possible complications of pinching and kinking of the catheter.

Object Motion Analysis and Interpretation in Video

Dan Song,Miyoung Cho,Pankoo Kim 한국정보과학회 2004 한국정보과학회 학술발표논문집 Vol.31 No.2Ⅱ

With the more sophisticated abilities development of video, object motion analysis and interpretation has become the fundamental task for the computer vision understanding. For that understanding, firstly, we seek a sum of absolute difference algorithm to apply to the motion detection, which was based on the scene. Then we will focus on the moving objects representation in the scene using spatio-temporal relations. The video can be explained comprehensively from the both aspects: moving objects relations and video events intervals.

혈액투석환자에 발생된 스틸증후군에서 시행된 Distal Revascularization Interval Ligation 술식의 치료경험

송단(Dan Song),문철(Chul Moon) 대한외과학회 2008 Annals of Surgical Treatment and Research(ASRT) Vol.74 No.5

Purpose: The hand ischemia that’s related to the construction of a vascular access is a serious and occasionally devastating complication. The traditional options for treating ischemic steal syndrome related to a functioning dialysis access graft or fistula include banding or ligation. Yet these procedures are directed toward increasing the resistance in the fistula, and they have yielded unreliable results. The technique of distal revascularization interval ligation provides satisfactory results in terms of healing of lesions, relief of symptoms and maintaining the vascular access. We report here on our experience with the DRIL procedure for relieving hand ischemia and maintaining the access patency in the setting of hemodialysis access-induced ischemia. Methods: We performed a retrospective review of all patients who underwent the DRIL procedure for treating access-induced ischemia. The physicians’ office charts and hospital records were reviewed to determine the demographic data, the time to development of symptoms, the access and bypass patency, limb salvage and patient survival. Results: From January 2001 and August 2005, the DRIL technique was used to treat 13 patients (8 women and 5 men: mean age: 59.6 years, 9 diabetic patients) who had functioning extremity fistulae and they presented with critical ischemia and steal syndrome. 9 patients had chronic ischemia, and acute ischemia developed in 4 patients. The fistulae were located at the elbow in 13 patients (4 brachiocephalic AVFs, 9 upperarm bridge grafts). The conduit used for the DRIL arterial bypasses (13 brachiobrachial bypasses) was the great sahpenous vein graft in 12 patients and an artificial graft was used in 1 patient. 2 patients had thrombotic occlusion in their arterial bypass. Open thrombectomy was used to treat all the patients. Limb salvage and maintenance of a functional fistula were achieved in 100% of the patients. Conclusion: The DRIL procedure is the effective, suitable treatment for relieving hand ischemia without sacrificing the fistula. We recommend the DRIL procedure to all access surgeons as the good choice for dealing with the complex problems of steal syndrome, which is induced by a functioning AV access.

자동화된 수면 방추파 검출기의 성능 비교 분석 및 피험자별 최적화

송단(Dan Song),최진영(Jinyoung Choi),전성찬(Sung Chan Jun) 한국HCI학회 2019 한국HCI학회 학술대회 Vol.2019 No.2

수면 방추파(Sleep spindle)는 사람의 수면 주기 가운데 수면 2 단계에 주로 나타나는 뇌 활동이다. 뇌 발달과 학습에서의 역할 때문에, 수면 방추파에 대한 생물학적, 임상적 관심이 급속히 증가하고 있다. 본 연구를 통해 공개되어 있는 자동화된 수면 방추파 검출기들(Automated sleep spindle detectors)을 중년층 수면 질환 환자 피험자들의 수면다원검사 데이터베이스로부터 획득한 수면뇌파 및 기존에 검출된 수면 방추파 정보에 적용하여, 자동화된 검출기의 성능을 객관적인 방법으로 평가했다. 기존의 Parameter 를 이용하여 자동화된 검출기의 성능을 평가한 후, 성능을 향상하기 위해 각 자동화된 검출기의 Parameter 변화를 시도해서 피험자 별로 자동화된 검출기를 최적화했다. 자동화된 검출기의 성능을 비교 분석한 결과, 대체적으로 Precision 이 높은 경우 Recall 이 낮고, 반대로 Recall 이 높은 경우 Precision 이 낮은 서로 상반된 특징을 나타냈다. 피험자 별로 차이가 심했던 점과 특정 자동화된 검출기가 최악의 성능을 나타냈던 점에 대해 재고의 여지가 있으며, 2 개 또는 그 이상의 자동화된 검출기들을 조합하거나 자동화된 수면 방추파 검출에 딥 러닝 방법을 적용해서 자동화된 수면 방추파 검출 성능을 개선할 수 있는지 검증할 필요가 있다.

혈액투석 인조혈관 동정맥루에 합병된 혈청종의 치료

송단(Dan Song),문철(Chul Moon) 대한외과학회 2006 Annals of Surgical Treatment and Research(ASRT) Vol.70 No.1

혈액투석중인 환자에서 쇄골하정맥 폐쇄증에 대한 액와-내경정맥 우회술의 임상 경험

송단(Dan Song),문철(Chul Moon) 대한외과학회 1997 Annals of Surgical Treatment and Research Vol.53 No.4