A New Design of the Interrogating Waves for Medical Ultrasonic Imaging Based on Wavelets and Subband Filter Banks: A Simulation Study

양윤석,Yang Yoon Seok The Korea Society of Medical and Biological Engine 2004 의공학회지 Vol.25 No.6

의료용 초음파 영상 장비는 안전하면서도 사용이 편리할 뿐 아니라, 인체 내부의 구조적 영상을 포함하여 혈류나 내부 장기의 움직임에 이르기까지 진단을 위한 다양한 정보를 제공한다. 뿐만 아니라 조직 특성화 영상에서는 반사된 초음파 신호로부터 생체 조직의 물리적인 특성을 파악하여 진단에 활용하기도 한다. 하지만 영상의 획득을 위해 사용하는 탐침용 초음파 펄스 신호는 인체내부를 거쳐 그 흔적이 반사신호에 남게 되고, 이는 영상의 화질 저하로 이어져 미세한 조직이나 인접한 부분의 세밀한 관찰이 어려운 단점이 있다. 이를 해결하기 위한 다양한 연구가 시도 되었으나, 한정된 반사 신호로부터 탐침 펄스의 영향을 제거하고 매질의 특성을 복원하는 데에는 어려움이 있었다. 본 연구에서는 wavelet 과 subband filter bank 에 기반한 새로운 탐침용 초음파 펄스 및 그에 따른 영상획득 방법을 제안하였다. Perfect reconstruction (PR) 조건을 만족하는 일련의 wavelet filter 세트를 초음파 펄스로 구현하여 탐침에 사용하고, 반사되어온 신호를 적절히 재조합 하면 탐침 펄스의 영향이 배제되어, 매질의 세밀한 특성을 복원한 영상을 얻게 된다. 이는 조직 특성화 영상등을 위해 중요한 정보가 된다. 검증을 위해 2종류 (A-mode 와 B-mode) 의 초음파 영상 시뮬레이션에서, 제안된 방법으로 영상을 획득하였다. 그 결과, 탐침 대상의 주파수 특성을 복원할 수 있었으며, 기존의 방법에 비해 향상된 화질의 초음파 영상을 얻을 수 있었다. Medical ultrasonic imaging is a useful imaging facility known to be most safe and easy. It enables physicians to observe the inside structures of the bodies, blood flow, and motions of internal organs. Some physical properties of biologic tissues can also be estimated from backscattered sounds. However, the ultrasonic pulses interrogating the living organisms leave their footprints in the returning signals during imaging. Some significant details are buried in the footprints and their overlaps from adjacent particles. These distortions also decrease the quality of the images. Many research efforts have been made to enhance the image quality and to recover the acoustic information in various ways. In this study, a new interrogation method based on the wavelet and subband filter bank is proposed. It adopts the subband wavelet filters satisfying the perfect-reconstruction (PR) conditions as the interrogating pulses to restore the details useful in tissue characterization and to enhance the image quality. The proposed method was applied to two types of simulations of ultrasonic imaging. The results showed its ability to restore the detailsin the simulated interrogation of biologic tissues, and verified the improved image quality in the simulated imaging of general ultrasonic phantom compared with the conventional method.

개인 휴대 단말기 (PDA)를 기반으로 한 휴대용 E-Nose의 개발

양윤석 ( Yoon Seok Yang ),김용신 ( Yong Shin Kim ),하승철 ( Seung Chul Ha ),김용준 ( Yong Jun Kim ),조성목 ( Seong Mok Cho ),표현봉 ( Hyeon Bong Pyo ),최창억 ( Chang Auck Choi ) 한국센서학회 2005 센서학회지 Vol.14 No.2

N/A The electronic nose (e-nose) has been used in food industry and quality controls in plastic packaging. Recently it finds its applications in medical diagnosis, specifically on detection of diabetes, pulmonary or gastrointestinal problem, or infections by examining odors in the breath or tissues with its odor characterizing ability. Moreover, the use of portable e-nose enables the on-site measurements and analysis of vapors without extra gas-sampling units. This is expected to widen the application of the e-nose in various fields including point-of-care-test or e-health. In this study, a PDA-based portable e-nose was developed using micro-machined gas sensor array and miniaturized electronic interfaces. The rich capacities of the PDA in its computing power and various interfaces are expected to provide the rapid and application specific development of the diagnostic devices, and easy connection to other facilities through information technology (IT) infra. For performance verification of the developed portable e-nose system, Six different vapors were measured using the system. Seven different carbon-black polymer composites were used for the sensor array. The results showed the reproducibility of the measured data and the distinguishable patterns between the vapor species. Additionally, the application of two typical pattern recognition algorithms verified the possibility of the automatic vapor recognition from the portable measurements. These validated the portable e-nose based on PDA developed in this study.

Emotional and Cognitional Characteristics of a Rape and Femicide Criminal Analyzed by Interview and Test

양윤석(Yoon-seok Yang),이준희(June-hee Lee),이양(Yang Lee) 영곡사회심리발달학회 2023 사회심리발달연구 Vol.4 No.2

Objectives This study aims to analyze the psychological processes of sexual violence, of which a criminal of rape and femicide was the target. Methods For the methods, phenomenological interviews and psychological tests were used. Results The results are abstracted: First, the interviews implied that he had perceived little stress in his home physical life but had not been cared for positively by his parents. Second, the tests showed that intelligence was high, but impulse motivation and negative self-esteem were high. Conclusions Contributing to the prevention of sexual violence and the education of personality, this study suggests that sexual violence is prescribed by the disregard of early education, which accumulates an impulsive and negative self.

전자연동장치 안전성 평가에 대한 연구

양윤석(Yang Yoon Seok),이종우(Lee Jong Woo) 한국철도학회 2006 한국철도학회 학술발표대회논문집 Vol.- No.-

Railway signal interlocking device with the reverse unit control device which is most important from country season, the subway and the high-speed railroad back, electric relay boarding and lodging accomplishes the master and servant and it comes and before from the Japanese back and an electronic interlocking device, a zone one interest in updated technology introduction Great Britain, Germany, Sweden and the United States, it quarrels about under developing it puts to practical use even from our country it shows. About reasoning lower our country subway or the country closing up shop stem there is not a possibility of throwing away the impression where the exhibition hall of foreign nation signal system is being turning out. Consequently is enormous a system well expense at the foreign corporation about under paying Oh!, it understands, with difficult always it is exposed to it is an actuality in the accident which is dangerous. In like this point of view first piece which is important securing safety of system from electronic anger of electronic interlocking device.

휴대용 전자 후각 장치에서 다채널 마이크로 센서 신호의 영상 정합을 이용한 가스 인식

양윤석(Yoon seok Yang) 大韓電子工學會 2011 電子工學會論文誌-SC (System and control) Vol.48 No.2

휴대용 인공 전자 후각 시스템 (E-nose) 의 가스 측정 환경은 실험실 내의 정교하게 제어되는 환경과 달리 온도, 농도, 기체시료의 유속 등의 외부 요인의 변동이 매우 심하다. 이런 환경에서도 사용 가능한 단순하고 강인하고 정확한 가스 패턴 인식알고리듬의 개발은 마이크로 바이오 센서의 발달과 함께 확대되고 있는 휴대용 및 소형 측정 진단 시스템에 있어 매우 중요하다. 본 연구에서는 PDA 기반의 휴대용 전자 후각 시스템을 활용해 실제 변화하는 환경에서 다채널 마이크로 센서로부터 감지되는 가스 신호를 수집하고, 여기에 영상 정합 기법을 적용하여 알고리듬의 강인성과 향상된 정확도를 검증하는 것을 목표로 하였다. 제안된 방법을 6종류의 가스 시료에 대한 7채널 마이크로 센서의 휴대 환경 측정 데이터에 적용하고,기존의 최대 민감도 특징 추출 기법과 비교한 결과, 외부 환경의 변동에 영향 받지 않는 안정된 인식 성능 뿐 아니라 기존의 방법으로 구별하기 어렵던 2종의 유사한 가스 시료에 대해서도 정확한 구분이 가능함을 보였다. 제안된 방법은 다양한 환경 변화에 노출되는 유비쿼터스 센서 네트워크 (USN) 의 데이터 처리에도 쉽게 응용될 수 있을 것이며, 응용 현장에서 높은 안정성과 정확성을 요구하는 휴대용 의료 진단, 환경 감지 기술의 실용화에 큰 도움을 줄 수 있을 것으로 기대한다. Portable artificial electronic nose(E-nose) system suffers from noisy fluctuation insurroundings such as temperature, vapor concentration, andgas flow, because its measuring condition is not controled precisely as in the laboratory. Itis important to develop a simple and robust vapor recognition technique applicable to this uncontrolled measurement, especially for the portable measuring and diagnostic system which are expanding its area with the improvements in micro bio sensor technology. This study used a PDA-based portable E-noseto collect the uncontrolled vapor measurement signals, and applied the image matching algorithm developed in the previou study on the measured signal to verify its robustness and improved accuracy inportable vapor recognition. The results showed not only its consistent performance under noisy fluctuation in the portable measurement signal, but also an advanced recognition accuracy for 2 similar vapor species which have been hard to discriminate with the conventional maximum sensitivity featur extraction method. The proposed method can be easily applied to the data processing of the ubiquitousensor network(USN) which are usually exposed to various operatingc onditions. Further more, it will greatly help to realize portable medical diagnostic and environment monitoring system with its robust performance and high accuracy.

이차감염된 굳은살로 오인된 발바닥의 염증성 표피낭종 1예

양윤석 ( Yoon Seok Yang ),박소은 ( So Eun Park ),신수정 ( Soo Jung Shin ),유창선 ( Chang Sun Yoo ),김철우 ( Chul Woo Kim ),김상석 ( Sang Seok Kim ) 대한피부과학회 2014 대한피부과학회지 Vol.52 No.2

제대혈 천자술 112예의 임상적 분석

조윤성 ( Yoon Seong Cho ),이병관 ( Byung Kwan Lee ),이원진 ( Won Jin Lee ),박미혜 ( Mi Hye Park ),오관영 ( Young Kwoan Oh ),양윤석 ( Yun Seok Yang ),황인택 ( In Taek Hwang ),박준숙 ( Joon Suk Park ) 대한산부인과학회 2002 Obstetrics & Gynecology Science Vol.45 No.9

목적 : 산전 진단에 있어서 진단적 제대혈 천자술의 안정성 및 효용성을 알아보고자 본 연구를 시행하였다. 연구 방법 : 1998년 3월부터 2002년 2월까지 초음파 유도하 경피적 제대혈 채취를 112명의 산모에서 시행하였고, 제대혈 천지술을 시행하였던 112명의 기록을 조사하였다. 결과 : 대상 산모의 임신 주수는 17주에서 36주 사이였다. 산모의 평균 연령은 29.6세이고 제대혈 천자 당시의 평균 임신 주수는 27.8주였다. 83예에서 (74.1%) 비정상적인 초음파 소견으로 적응중이 되어 빠른 핵형 분석을 시행하엿다. 112예 중 105예에서 (93.8%) 성공적으로 태아 혈액을 채취하였고, 그 중 99예에서는 (88.4%) 첫 번째 시도에서 성공하였다. 103예 중 9예에서 (8.7%) 염색체 이상이 발견되었고 초음파상 구조적 이상을 보였던 70예 중 8예에서 (11.4%) 비정상적인 염색체 소견을 보였다. 제대혈 천자술과 연관된 합병증으로는 태아서맥이 3예에서 (2.7%) 발생하였다. 결론 : 본 연구에서 제대혈 천자술은 태아의 산전 진단에 유용하고, 비교적 안전하며, 효율적인 방법으로 사료된다. Objective : This study was performed to assess the safety and efficacy of the diagnostic cordocentesis in prenatal diagnosis. Methods : Between March 1998 and February 2002, percuteneous umblical cord blood samplings under the ultrasonographic guidance were performed in 112 patients. We reviewed the medical records of 112 patients who were performed cordocentesis. Results : Gestational age ranged between 17 and 36 weeks. The mean maternal age was 29.6 years and the mean gestational age at the time of cordocentesis was 27.8 weeks. Among the patients, 83 cases (74.1%) were done with the indication of abnormal sonographic finding and followed by rapid karyotyping. Pure fetal blood was successfully obtained in 105 cases of 112 cordocentesis (93.8%). 99 cases (88.4%) were done successfully at the first attempt. Chromosomal abnormalities were found in 9 of 103 fetuses (8.7%). Abnormal chromosomal patterns were found in 8 of 70 fetuses (11.4%) with structural anomalies detected by ultrasonography. The procedure-related complication, fetal bradycardia occured in 3 cases (2.7%). Conclusion : We conclude that cordocentesis is a useful, relatively safe, and effective procedure for prenatal diagnosis.

유륜에 발생한 후천성 국한성 림프관종

김진혜 ( Jin Hye Kim ),양윤석 ( Yoon Seok Yang ),조수익 ( Soo Ick Cho ),정보영 ( Bo Young Chung ),박천욱 ( Chun Wook Park ),이철헌 ( Cheol Heon Lee ),김혜원 ( Hye One Kim ) 대한피부과학회 2013 대한피부과학회지 Vol.51 No.6

Lymphangioma is an uncommon, benign hamartomatous malformation that consists of dilated lymphatic channels lined by normal, single-cell lymphatic endothelia. The lymphangiomas are divided into cavernous lymphangioma, cystic hygroma, lymphangioma circumscriptum, and acquired progressive lymphangioma. Acquired lymphangioma circumscriptum usually occurs due to surgery, infection or radiotherapy, which leads to obstruction of lymphatic vessels. Clinically, the lesions appear as thick-walled, 2∼5 mm translucent vesicles. Spontaneous drainage of straw-colored to milky-white fluids may occur. Herein, we report an acquired lymphangioma circumscriptum of the nipple areola without preceding causes.

전력관리 시스템과 미생물연료전지 스택 연결방법에 따른 출력 변화 연구

김태영(Taeyoung Kim),양윤석(Yoon Seok Yang),여정진(Jeong Jin Yeo),강석원(Sukwon Kang),백이(Yee Paek),권진경(Jin Kyung Kwon),장재경(Jae Kyung Jang) 한국신재생에너지학회 2018 한국신재생에너지학회 학술대회논문집 Vol.2018 No.4

수박과 멜론에 의해 유발된 구강 알레르기 증후군

김진혜 ( Jin Hye Kim ),양윤석 ( Yoon Seok Yang ),조수익 ( Spp Ick Cho ),박천욱 ( Chun Wook Park ),이철헌 ( Cheol Heon Lee ),김혜원 ( Hyeone Kim ) 대한피부과학회 2013 대한피부과학회지 Vol.51 No.9

Oral allergy syndrome (OAS) usually presents as an immediate swelling and itching sensation of the mouth and throat after ingestion of a food allergen. OAS may be the most common food allergy-related manifestation. Watermelon and melon belong to the Cucurbitaceae family and often show allergenic cross reactivity. Profilin is a 13 kda protein that is identified as a relevant pollen allergen in airborne pollen and related plant food allergies. Profilin is found in both watermelon and melon. Here we report a case of OAS to watermelon and melon in an 11year-old boy. He was positive to the skin prick test, patch test and oral challenge test with watermelon and melon.