실내 위치 측위를 통한 D2D 통신 성공 확률 (Opportunity Probability) 측정 및 예측

한규원(Kyuwon Han),남혜린(Hyelin Nam),박지훈(Jihoon Park),성명훈(Meonghoon Seong),김성륜(Seong-Lyun Kim) 한국통신학회 2022 한국통신학회 학술대회논문집 Vol.2022 No.2

본 논문에서는 실내 측위를 진행하고, 그 결과를 바탕으로 D2D 통신 성공 확률인 Opportunity probability (OP)를 예측 및 측정하여 그 값을 비교하는 실험을 소개한다. 실내 측위를 위해서 스마트폰의 관성 측위 센서와 이를 보정하기 위한 딥러닝 네트워크, 그리고 WiFi RTT를 융합한 측위 기법이 사용되었다. 그 결과 OP값을 중위값 90% 이상으로 예측하는 데 성공하였다.

한약재의 대사 및 독성의 기전과 예방

박영철,김종봉,이선동,Park, Yeong-Chul,Kim, Jong-Bong,Lee, Sun-Dong 대한예방한의학회 2008 대한예방한의학회지 Vol.12 No.1

In recent years, there has been a globally increasing application of herbal medicines and dietary supplements to treat various chronic diseases and to promote health. However, there are increasing clinical reports on the organ toxicities associated with consumption of herbal medicines. In general, most xenobiotics are metabolized by Phase I reaction(the main enzyme : cytochrome P450) and Phase II reaction. However, reactive oxygen species, free radicals and electrophils are produced inevitably during xenobiotics metabolism. These toxic species and metabolites are increased whenever the endogenous substances and enzymes for Phase II reaction not available. In addition, herbal-drug interactions are pharmacokinetic, with most actually or theoretically affecting the metabolism of the affected product by way of the cytochrome P450 enzymes. This review updated the knowledge on metabolic activation of herbal components and its clinical and toxicological implications. Also, the possible way for preventing the side-effects by herbal-medicine use was suggested.

건축분야 임대형 민자사업 협상단계 쟁점 분석에 관한 연구

박영철,이건,이현철,고성석,Park, Yeong-Cheol,Lee, Gun,Lee, Hyun-Chul,Go, Seong-Seok 한국건설관리학회 2009 한국건설관리학회 논문집 Vol.10 No.5

본 연구는 BTL사업 실시협약을 위한 협상단계에서의 쟁점이 되는 항목의 분석 및 그 발생 원인을 찾아보고 해결방안을 제시하고자 하였다. 이에 기 수행되었거나 또는 수행중인 협상에서 논의되고 쟁점화 되는 항목에 관하여 주무관청과 사업참여자를 대상으로 협상참여 주체들이 인식하고 있는 쟁점화정도를 분석하였다. 또한 협상단계 각 분야별 쟁점항목들의 계층 분석방법을 통한 쌍대비교를 통해 가중치를 산정하고 그 쟁점화정도를 정량적으로 도출하였다. 최종적으로 1차 계층의 6개 협상분야 중 4개 분야에 대한 발생원인 각 2개, 2개 분야에 대한 발생원인 각 1개를 도출한 후 그에 대한 해결방안을 제시하였다. This study aimed to find major issues on negotiations of the BTL project, to analysis the degree, and to investigate the underlying cause and propose solutions. Data were collected from authorities in charge and the companies which have participated in BTL projects. Also, the weights of major issues were analyzed using Analytic Hierarchy Process method(AHP), which uses pair-wise comparison between variables, and the degree of them were listed in the quantitative way. As a result, 4 part had each 2 reasons and others had one reason among 6 negotiation parts of first step. In addition, the solutions were indicated.

웨이블릿을 이용한 QRS complex 검출 알고리즘의 고정 소수점 연산 최적화

박영철,Park, Young-chul 한국정보전자통신기술학회 2014 한국정보전자통신기술학회논문지 Vol.7 No.3

본 논문에서는 웨이블릿 변환을 통하며 QRS complex를 검출 하며, 32비트 고정 소수점 연산이 가능한 프로세서에도 동작하도록 알고리즘 최적화 기법을 제시한다. 먼저 입력 ECG 신호를 밴드 패스 필터를 통과 시키고, 3개의 서로 다른 웨이블릿 함수를 하나로 병합한 웨이블릿 함수를 이용하여 웨이블릿 변환을 하며, 다음으로 시간 평균 함수를 뒤에 마지막으로 QRS complex를 검출 한다. 제안 알고리즘은 MIT-BIH arrhythmia database에 적용하여 검증한다. 모든 과정은 32비트 고정 소수점 연산으로 구현되며, 삼각함수 같은 복잡한 연산은 테이블화 하였다. 검출 알고리즘은 컴퓨터 시뮬레이션을 통해 평가 한다. In this study, QRS complex is detected by Wavelet Transform and it can be worked in 32bit fixed point operation thought optimization. First, ECG signal is passed though band pass filter. Second, it is transformed using one-band combined wavelet function from 3-band wavelet function. Third, it is passed though moving window integral. Finally, QRS complex is detected by decision rule. The proposed algorithm is evaluated using MIT-BIH arrhythmia database. Its all of process make progress 32-bit fixed-point operation and it makes table that high complexity operations like trigonometrical function. The detection algorithm evaluate through computer simulation.

일부 동물성 한약재의 독성과 안전성등급화 - 봉독, 사독, 반묘와 오공을 중심으로 -

박영철,이선동,Park, Yeongchul,Lee, Sundong 대한예방한의학회 2016 대한예방한의학회지 Vol.20 No.1

Objectives : About 13% of the medicines used by traditional korean medicines(TKM), are called animal medicines and are derived from non-herbal sources such as animals and insects. However, the clinical use of these preparations from animal medicines is often based on tradition and belief, rather than on evidence of toxicity and efficacy. As a result, animal medicines containing toxin have caused serious problems from injecting patients with venom. Here, various venoms frequently used as TKM were reviewed in terms of their instinct toxity and tried to estimate their safety classification. Methods : The estimation of safety classification was based on human equivalent dose(HED)-based MOS (margin of safety) and clinical dose applied for patients. Results and Conclusions : Except that of snake venom due to no clinical dose, they were evaluated as class 3 for bee venom, class 4 for cantharidin, toxin from blister beetle, and class 1 for venom from scolopendrid. In conclusion, animal medicines showed a wide range of safety classification from class 1 to class 4. This wide range is estimated to result from extremely limited applications of each venom for patients because of their strong toxicity. However, it should be cautious for application in clinics since animal medicines can produce anaphylactic reactions particularly after veinous administration even with a tiny amount of venom.

광대역 잡음의 전역 감쇠를 위한 에너지 밀도 제어

박영철,윤정현,윤대희,차일환,Park, Young-Cheol,Yun, Jeong-Hyeon,Youn, Dae-Hee,Cha, Il-Whan 한국음향학회 1996 韓國音響學會誌 Vol.15 No.2

본 논문에서는 일차원 밀폐함 내의 광대역 소음을 제어하기 위한 에너지 밀도(energy density)제어 알고리듬의 성능을 평가한다. 주파수 영역에서 최적 능동 소음 제어 필터를 설계할 경우 종종 시간 영역에서 물리적으로 실현할 수 없는 결과를 얻게 된다. 이런 문제를 피하기 위해 본 논문에서는 시간 영역에서 문제를 해석한다. 이러한 접근 방법은 항상 물리적으로 실현 가능한 최적 제어기를 얻을 수 있게 해준다. 능동 소음 제어 시스템의 성능을 예측하기 위해 실시간 모의 실험 결과로부터 음압을 최소화 하는 것보다 에너지 밀도를 최소화 하는 것이 광대역 소음의 전역적인 감쇠(global attenuation)에 있어서 향상된 결과를 얻을 수 있음을 확인할 수 있다. 또한 특정 지점에서, 검출된 에너지 밀도를 최소화할 경우 밀폐함 내에 있는 위치 에너지를 최소화하는 방법에서 얻을 수 있는 결과와 유사한 정도의 소음 전역 감쇠를 얻을 수 있었다. 그리고 음압 자승 제어 방법과는 달리 에너지 밀도 제어 방법은 일차원 음장에서 사용하는 경우 오차 센서의 위치에 영향을 받지 않음을 알 수 있다. 본 논문은 또한 에너지 밀도 제어 알고리듬의 실제 구현시에 일반적으로 사용되는 두 개의 센서를 사용하는 구현 기술을 살펴보고, 이 기술이 큰 성능 저하 없이 에너지 밀도 제어 알고리듬을 구현할 수 있음을 보인다. The performance of the energy density control algorithm for controlling a broadband noise is evaluated in a one-dimensional enclosure. To avoid noncausality problem of a control filter, which often happens in a frequency domain optimization, analyses presented in this paper are undertaken in the time domain. This approach provides the form of the causally constrained optimal controller. Numerical results are presented to predict the performance of the active noise control system, and indicate that imp개ved global attenuation of the broadband noise can be achieved by minimizing the energy density, rather than the squared pressure. It is shown that minimizing the energy density at a single location yields global attenuation results that are comparable to minimizing the potential energy. Furthermore, unlike the squared pressure control, the energy density control does not demonstrate any dependence on the error sensor location for this one-dimensional field. A practical implementation of the energy-based control algorithm is presented. Results show that the energy density control can be implemented using the two sensor technique with a tolerable margin of performance degradation.

독성대사체를 생성하는 다빈도사용 한약재의 안전성등급화 - 천궁, 당귀, 감초, 숙지황을 중심으로 -

박영철,이선동,Park, Yeong-Chul,Lee, Sundong 대한예방한의학회 2015 대한예방한의학회지 Vol.19 No.2

The new formular for herbal medicine-safety classification in terms of evidence-based medicine was developed and applied to evaluate various herbal medicines in the previous study. This study is aimed to evaluate the frequently-used herbal medicines inducing toxic metabolites or reactive intermediates(RI), such as Ligusticum wallichii Franch, Angelica sinensis, Glycyrrhizae Radix, Rehmanniae Radix, based on 6 safety grades calculated from human equivalent dose(HED)-based MOS(margin of safety). HED-based MOS can be explained as the ratio of theoretical ALD(approximate lethal dose) of human as $LD_1$(lethal dose of 1%)/ clinical maximum dose as $ED_{99}$(Effective dose of 99%). The herbal medicine showing the ratio less than 1 belongs to Class 1, but the herbal medicine showing the ratio more than 500 belongs to Class 6 with the lowest toxicity. As a result, they were evaluated as class 2 for Angelica sinensis and Glycyrrhizae Radix, class 3 for Ligusticum wallichii Franch and Rehmanniae Radix. These resultant grades for 4 herbal medicines were lower than the grade expected under consideration that these herbal medicines are used very frequently in oriental clinics. These low grades would be due to their ingredients which is biotransformed to toxic metabolites.

한약의 약물상호작용 기전과 연구방향 - 독성학적인 측면을 중심으로 -

박영철,김명동,이선동,Park, Yeong-Chul,Kim, Myung-Dong,Lee, Sun-Dong 대한예방한의학회 2011 대한예방한의학회지 Vol.15 No.1

Objectives : The mechanisms for korean traditional medicine-drug interaction has not been well reviewed in spite that the chance for co-administration with western drugs or diet supplements has been increased. Especially, it is well known that various cytochrome P450s play a major role in drug-drug interaction. Of course, Korean traditional medicines is not excluded in a view of metabolism or biotransformation by cytochrome P450. This article was focused on reviewing the possible roles of cytochrome P450 in Korean traditional medicine-drug interaction, Also, the directions for further studies were suggested in terms of Korean traditional medicine-drug interaction. Methods : New studies for korean traditional medicine-drug interaction were reviewed and summarized in terms of cytochrome P450 activities by various Korean traditional medicines and western drugs. Results and Conclusions : Even if a few studies related to Korean traditional medicine-drug interactions was carried out, almost no studies for Korean traditional medicine-drug interactions has been found in a view of cytochrome P450. It was suggested that Korean traditional medicines and their decoction should be analyzed that how they effects on cytochrome P450, expecially CYP 1, 2, 3 families and how they interact with western drugs.

도서관인의 명암(明暗) - 독서명문대학을 꿈꾸는 숭실대학교 독서인재프로그램

박영철,Park, Yeong-Cheol 한국도서관협회 2012 圖協會報 Vol.53 No.7

생체용 Ti-18Nb-6Zr-XO (X = 0~1.5at%) 합금의 형상기억특성에 미치는 산소 농도의 영향

박영철,옥지면,오정화,박수호,이준희,김재일,Park, Young-Chul,Ock, Ji-Myeon,Oh, Jeong-Hwa,Park, Su-Ho,Lee, Jun-Hee,Kim, Jae-Il 한국재료학회 2011 한국재료학회지 Vol.21 No.11

The effect of oxygen on the shape memory characteristics in Ti-18Nb-6Zr-XO (X = 0-1.5 at%) biomedical alloys was investigated by tensile tests. The alloys were fabricated by an arc melting method at Ar atmosphere. The ingots were cold-rolled to 0.45 mm with a reduction up to 95% in thickness. After severe cold-rolling, the plate was solution-treated at 1173 K for 1.8 ks. The fracture stress of the solution-treated specimens increased from 450 Mpa to 880 MPa with an increasing oxygen content up to 1.5%. The fracture stress increased by 287MPa with 1 at% increase of oxygen content. The critical stress for slip increased from 430 MPa to 695 MPa with an increasing oxygen content up to 1.5 at%. The maximum recovery strain of 4.1% was obtained in the Ti-18Nb-6Zr-0.5O (at%) alloy. The martensitic transformation temperature decreased by 140 K with a 1.0 at% increase in O content, which is lower than that of Ti-22Nb-(0-2.0)O (at%) by 20 K. This may have been caused by the effect of the addition of Zr. This study confirmed that addition of oxygen to the Ti-Nb-Zr alloy increases the critical stress for slip due to solid solution hardening without being detrimental to the maximum recovery strain.