Development of a Chest‑Belt‑Type Biosignal‑Monitoring Wearable Platform System

Joo‑Hyeon Lee,Hyun‑Seung Cho,Jin‑Hee Yang,Sang‑Min Kim,Jeong‑Whan Lee,Hwi‑Kuen Kwak,Je‑Wook Chae 대한전기학회 2020 Journal of Electrical Engineering & Technology Vol.15 No.4

The purpose of this study was to develop a wearable platform system that can detect and acquire a soldier’s biosignals (i.e., heart activity signal, respiration rate, etc.) in a nonrestrained, unconscious manner. These detected biosignals are transmitted to a processing device to analyze and monitor the soldier’s physical status. To achieve this, textile-based heart activity electrodes and a strain gauge sensor for the respiration signal measurement were developed, and their performances in detecting each signal were verifed. These sensors were embedded in a chest belt to design a wearable platform that can simultaneously measure heart activity and respiration signals. The sensor part of the chest belt has a dual layer structure to detect high-quality signals. Stretch fabric was used on the outer layer and a respiration sensor was attached to the belt. On the inside layer, a non-stretch fabric was used as the base fabric and a heart activity-sensing electrode, that is capable of taking measurements using a modifed lead-II heart activity signal induction method, was embroidered onto the fabric. Subjects were asked to wear the chest belt, and a biosignal processor module was attached to verify the system’s performance while simultaneously acquiring the heart activity and respiration signals. More specifcally, it was confrmed that the two signals were detected in a stable. It is expected that the biosignal-monitoring wearable platform system developed in this study will be able to efectively analyze and monitor soldiers’ biosignals.

Effect of Al and Mg Contents on Wettability and Reactivity of Molten Zn–Al–Mg Alloys on Steel Sheets Covered with MnO and SiO2 Layers

Joo‑Youl Huh,Min‑Je Hwang,Seung‑Woo Shim,Tae‑Chul Kim,Jong‑Sang Kim 대한금속·재료학회 2018 METALS AND MATERIALS International Vol.24 No.6

The reactive wetting behaviors of molten Zn–Al–Mg alloys on MnO- and amorphous (a-) SiO2-covered steel sheets wereinvestigated by the sessile drop method, as a function of the Al and Mg contents in the alloys. The sessile drop tests werecarried out at 460 °C and the variation in the contact angles (θc) of alloys containing 0.2–2.5 wt% Al and 0–3.0 wt% Mg wasmonitored for 20 s. For all the alloys, the MnO-covered steel substrate exhibited reactive wetting whereas the a-SiO2-coveredsteel exhibited nonreactive, nonwetting (θc > 90°) behavior. The MnO layer was rapidly removed by Al and Mg contained inthe alloys. The wetting of the MnO-covered steel sheet significantly improved upon increasing the Mg content but decreasedupon increasing the Al content, indicating that the surface tension of the alloy droplet is the main factor controlling its wettability. Although the reactions of Al and Mg in molten alloys with the a-SiO2 layer were found to be sluggish, the wettabilityof Zn–Al–Mg alloys on the a-SiO2 layer improved upon increasing the Al and Mg contents. These results suggest that thewetting of advanced high-strength steel sheets, the surface oxide layer of which consists of a mixture of MnO and SiO2,withZn–Al–Mg alloys could be most effectively improved by increasing the Mg content of the alloys.

9-12%Cr강의 첨가원소 및 열처리에 따른 미세조직거동과 경도변화

주성욱,유정훈,신기삼,허성강,이재현,석진익,김병훈,김정태 국립7개대학공동논문집간행위원회 2004 공업기술연구 Vol.4 No.-

9-12%Cr steel are getting increasing attention for expanded application as high temperature materials applicable for gas turbine compressors, steam turbine rotors, blade and casing. For efficient and extensive application of 9-12%Cr steel, the data in addition to the improvement of mechanical properties on the correlation of microstructural evolution and mechanical properties are inevitable and thus the investigation in this study is performed for the determination for the specimens heat-treated at 600, 650 and 700℃ for 1000, 3000 and 5000hrs. The microstructure of as-received specimen was tempered martensite, with a high dislocation density and secondary phases. Upon high temperature heat-treatment, the martensite lath got larger and dislocation density decreased resulting the reduction of the strength. In addition, sharp growth of secondary phases was observed in the specimen heat-treated at 700℃ for 5000hrs. A specimen aged at 600℃ and 650℃ Laves phase was observed. The hardness showed close relationship with the secondary phase particle and dislocation density.

액상 실리카륨을 혼입한 콘크리트의 파괴특성

박제선,민창동,김태경,이주형 江原大學校 産業技術硏究所 1995 産業技術硏究 Vol.15 No.-

The experimental study is conducted to analyze the characteristics of concrete included silica fume. The workability of concrete is controled by the ratio of mixture, such as superplastcizer, based on the constant rates of sand and cement. It is concluded that the strength and the frectu Toughness of concrete with silica fume are very improved.

Mycophenolic Acid가 PDGF에 의해 증식 유도된 흰쥐 혈관평활근 세포에서 NAD(P)H Oxidase, 세포내 활성산소족 및 Mitogen-activated Protein Kinases에 미치는 영향

박제현,하헌주,김명수,허규하,김유선 이화여자대학교 약학연구소 2004 藥學硏究論文集 Vol.- No.14

Background: Vascular smooth muscle cell (VSMC) proliferation plays an important role in the development and progression of chronic allograft vasculopathy as in atherosclerosis. We already reported that mycophenolic acid (MPA) inhibited VSMC proliferation, cellular reactive oxygen species (ROS) and mitogen-activated protein kinases (MAPK) in human VSMCs. In this study, we examined further molecular mechanisms involved in the anti-proliferative effect of MPA in rat VSMCs. Methods: Primary rat VSMCs were stimulated with PDGF-BB 10 ng/mL in the presence or absence of MPA and various kinds of cell signaling inhibitors. Cell proliferation was assessed by [H³]-thymidine incorporation, NAD(P)H oxidase subunits mRNA expression by RT-PCR, dichlorofluorescein-sensitive cellular ROS by FACS, and the activation of PDGF receptor-β (Tyr 751), racl, and MAPK by Western blot analysis. Results: PDGF increased cell proliferation and cellular ROS, activation of PDGF receptor-β (Tyr 751), racl, expression of p22phox and MOX1 mRNA, ERK 1/2, and p38 MAPK, compared to control. MPA inhibited up-regulation of racl phosphorylation, p22phox and MOX1 mRNA expression, cellular ROS, and phosphorylation of ERK 1/2 and p38 MAPK. However, MPA did not affect PDGF receptor-β (Tyr 751) activation. Wortmannin, diphenyleniodonium (DPI), trolox, and NAC, each inhibited PDGF-induced ERK 1/2 and p38 MAPK activation. PD98059 and p38 MAPK inhibitor also inhibited PDGF-induced cell proliferation. Conclusion: These results suggest that MPA inhibits PDGF-induced VSMC proliferation through inhibiting NAD(P)H oxidase-dependent cellular ROS leading to ERK 1/2 and p38 MAPK activation. 배경 : 혈관평활근 세포의 증식은 장기이식 후 발생하는 혈관경화증이나 동맥경화증의 발생과 진행에 중요한 역할을 한다. Mycophenolic acid (MPA)는 강력한 면역억제제로서 혈관평활근 세포의 증식도 억제한다. 본 연구는 사람의 혈관평활근 세포에서 MPK가 세포증식에 관여하는 신호전달계인 활성산소족과 mitogen-activated protein kinases(MAPK) 활성화를 억제하는 기존의 연구결과를 바탕으로, PDGF에 의해 증식 유도된 흰쥐 혈관평활근 세포에서 MPA가 세포의 증식을 억제하는 기전을 검색하였다. 방법 : 일차 배양한 흰쥐 혈관평활근 세포를 PDGF-BB 10 ng/mL로 자극하였고, MPA를 비롯한 여러 종류의 신호전달 억제제는 PDGF를 투여하기 1시간 전에 투여하였다. 세포증식은 [H³]-thymidine incorporation으로, NAD(P)H oxidase subunit의 mRNA 표현은 RT-PCR로, dichlorofluorescein에 민감한 세포내 활성산소족은 FACS 방법으로, 그리고 PDGF 수용체-β (Tyr 751), racl 및 MARK 활성하는 Western blot으로 각각 분석하였다. 결과 : PDGF는 PDGF 수용체-β (Tyr 751)의 활성화 및 NAD(P)H oxidase subunit 중 racl의 활성화와 p22phox와 MOX1의 mRNA 표현을 대조군에 비하여 유의하게 증가시켰다. MPA는 PDGF 수용체의 활성화에는 영향을 주지 않았으나, racl의 활성화, p22phox와 MOX1의 mRNA 표현의 상향 조절, 세포내 활성산소족, 그리고 ERK 1/2와 p38 MAPK의 활의한 EFK 1/2와 p38 MAPK 활성화와 세포 증식을 억제하였다. PD98059와 p38 MAPK 억제제는 PDGF에 의한 혈관평활근 세포의 증식을 억제하였다. 결론 : 본 연구결과는 MPA가 NAD(P)H oxidase를 억제함으로써 세포내 활성산소족 생산과, MAPK 활성화를 억제함으로써 PDGF에 의하여 유도되는 혈관평활근 세포의 증식을 억제함을 시사하였다.

경도 및 중등도 근시환자에서 PRK 후 교정법에 따른 인공수정체 도수 비교

신제원,김중곤,송병주 한양대학교 의과대학 2002 한양의대 학술지 Vol.22 No.1

To compare IOL powers which are calculated by post-op keratometric(K) values and refraction derived K values, and by refraction corrected method, respectively, in patients who have been treated with excimer laser photorefractive keratectomy(PRK) for mild to moderate myopia. A total of 38 consecutive eyes of 23 patients who were treated with PRK for mild to moderate myopia have been followed up for more than 6 months. IOL powers from SRK/T formula by post-op K values and refraction derived K values were compared with IOL powers by refraction corrected method. The mean values of IOL powers using post-op K values, refraction derived K values, and refraction corrected method were 20.69±0.93(18.21 to 22.93) diopter(D), 20.81±0.88 D(18.60 to 22.43), and 21.26±0.79 D(19.08 to 23.03) respectively. There was no significant statistical difference between the mean values of IOL powers using post-op K values and refration derived K values (p〉0.05). However, the mean value of IOL powers by refraction corrected method was statistically higher than other two values(p〈0.05). In patients with excimer laser PRK treatment for mild to moderate myopia, IOL power using refraction corrected method was statistically higher than IOL power using post-operative K values and refraction derived K values.

산업폐기물인 폐주물사를 혼입한 콘크리트의 최적배합설계

박재선,김태경,백민경,이주형,윤경구,김남윤 강원대학교 석재복합신소재제품연구센터 1997 석재연 논문집 Vol.2 No.-

산업폐기물인 폐주물사를 재활용하여 에너지 절감과 환경오염효과를 얻을 수 있다. 반요인실험법을 사용하여 폐주물사를 잔골재에 일정비율 치환한 콘크리트의 최적배합설계 제시를 위한 예비실험에서 물-시멘트비, 폐주물사의 잔골재 치환율, 잔골재율, 슬럼프와 같은 주요변수와 변수사이의 2차상호작용을 파악하였다. 예비실험결과 폐주물사의 잔골재치환율을 70%까지 실시하였을 때 폐주물사를 혼입한 콘크리트의 강도발현에 가장 중요한 변수는 물-시멘트비로 분석되었고 폐주물사의 잔골재치환율은 거의 영향이 없는 것으로 분석되어 폐주물사를 콘크리트의 잔골재로 대체할 수 있음을 알 수 있었다. 각 변수의 2차상호작용에서는 폐주물사의 잔골재 치환율과 잔골재율의 상관관계가 콘크리트의 강도발현에 가장 큰 영향을 미치는 것으로 나타났다. 목표압축강도에 대한 최적배합조건을 폐주물사의 잔골재 치환율에 따라 물-시멘트비, 잔골재율에 대해 제시하였다. The waste foundry sand might be recycled in concrete, saving energy and protect-ing environment. An half- factorial experiments were performed with the primarary variable such as water- cement raito, waste foundry sand substitution ratio, fine agg-regate ratio and slump as a preliminary study for optimum mix design of concrete. The preliminary study show that the water- cement ratio is the most important factor to the concrete strength, followed by slump. The substitute of waste foundry sand up to 70% has little infulence, indicating that it can substitute the fine aggregate without damaging the Concrete strength. The interaction between waste foundry sand substitution ratio and fine aggregate ratio was most significant to the concrete strength among the 2-way interaction variable. Only compressive strength affect to the formation of optimum mix design area as target compressive strengh becomes bigger. Optimum mix designs of concrete incorporating waste foundry sand, satisfying the target responses, were proposed in terms of waste foundry sand substitution ratio, water cement ratio and fine aggregate ratio.

진행성 비호지킨 림프종 환자에서 ICE 구제 요법에 의한 조혈모세포 가동화 후 자가 말초혈액 조혈모세포이식

이제중,이병환,김여경,변정래,이일권,박무림,정익주,김형준 대한조혈모세포이식학회 2003 대한조혈모세포이식학회지 Vol.8 No.1

연구배경: 비호지킨 림프종에서 자가 말초혈액 조혈모세포이식술이 폭넓게 이용됨으로 인해서, 높은 치료효과뿐만 아니라 조혈모세포의 가동화 효율이 높은 구제 요법이 요구되었다. 방법: 본 연구에서는 진행성 비호지킨 림프종에서 ICE 요법을 이용하여 조혈모세포를 가동화시킨 후 자가 말초혈액 조혈모세포이식이 시행하였던 환자를 후향적으로 분석하였다. 결과: 대상 환자의 중앙 연령은 38세(범위, 16~61)였으며, ICE 요법은 환자당 4주기(범위, 1~6주기)가 투여되었고, 투여 간격은 중앙값이 24일(범위, 16~36일)이었다. 고위험도 관해군을 제외한 13예의 환자 중 완전반응은 7예(53.8%), 부분반응은 4예(30.8%), 진행성질환은 2예(15.4%)를 보였다. 치료에 따른 3~4등급의 혈액학적 독성은 중성구감소증이 13예(81.3%), 혈소판감소증이 7예(42.8%)에서 관찰되었다. 조혈모세포 채집은 ICE 요법 후 중앙값이 12일(범위, 6~20일)에 시행되었고, 각 ICE 요법당 채집한 단핵구치는 중앙값이 5.75× 10^(8)/체중, CD34^(+) 세포는 중앙값이 1.25× 10^(6)/체중, CFU-GM치는 중앙값이 1.19× 10^(5)/체중이었다. 조혈모세포이식은 11예에서 시행되었고, 중앙 추적기간 401일에 평가한 2년 전체생존율은 70.1±14.7%, 1년 및 2년 무사건생존율은 각각 60.7±15.4%와 32.3±17.1%를 보였다. 결론: ICE 요법은 재발성/불응성 비호지킨 림프종 환자에서 높은 치료 반응률과 만족할 만한 조혈모세포 가동화를 보여 주었지만, 치료에 대한 순응도가 낮아서 투여 간격이 연장되는 문제점을 안고 있어서, 우리나라 환자의 실정에 적합한 구제요법에 대한 연구가 필요할 것으로 생각된다. Background: Due to the extensive application of high-dose chemotherapy with autologous peripheral blood stem cell transplantation (PBSCT), a salvage chemotherapeutic regimen with high response rate as well as effective capacity of PBSC mobilization is needed in non-Hodgkin's lymphoma (NHL). Methods: We analyzed the applicability of ICE (ifosphamide, carboplatin, and etoposide) regimen in NHL patients who underewent autologous PBSCT. Results: The median age was 38 years (range, 16~61 years), the patients received median 4 cycles (range, 1~6 cycles) of ICE regimen, and the median interval between each chemotherapeutic cycle was 24 days (range, 16~36 days). There were 7 (53.8%) complete responses, 4 (30.8%) partial responses, and 2 (15.4%) progressive diseases after ICE regimen. Toxicity included grade 3/4 neutropenia and throm bocytopenia in 13 (81.3%) and 7 (42.8%) patients, respectively. PBSC collection began on median day 12 (range, 6~20 days) after ICE therapy. The median number of mononuclear cells, CD34+ cells, and CFU-GM was 5.75× 10^(8)/kg, 1.25× 10^(6)/kg, and 1.19× 10^(5)/kg, respectively. With a median follow- up of 401 days, the patients who underwent autologous PBSCT had overall survival with 70.1±14.7% at 2 year and event free survival with 60.7±15.4% and 32.3±17.1% at 1 year and 2 years, respectively. Conclusion: ICE chemotherapy is an effective cytoreduction and mobilization regimen in patients with NHL, but profound myelosuppression with delayed recovery might pose difficulties in applying for Korean patients. Further evaluation for appropriate salvage regimens in Korean patients should be needed.

발아과정을 통한 3종 식물의 내염성 단백질 합성

정숙주,우제창 木浦大學校基礎科學硏究所 1997 基礎科學硏究誌 Vol.15 No.-

염분을 농도별로 첨가한 배지에서 유채와 무 0.2%때 발아율이 가장 높았다. 염분의 농도별 생장율을 조사한 결과 유채와 무에서 0.4%와 0.6%의 염분이 첨가 되었을 때 생장이 가장 좋았다. 3종 작물을 각기 다른 염분내성 단백질을 생산해내는 것으로 나타나서 유채는 35kD와 26kD의 단백질을 새로 생산해 내었으며 무는 40kD와 16kD 그리고 벼는 0.4%에는 30kD, 고농도에서는 20kD의 단백질을 생산했다. Germination rate of Brassica and Raphanus was observed highest rate at the 0.2% NaCl concentration. Growth rate of Brassica and Raphanus showed maximum value at the 0.4% and 0.6% respectively. Salt resistant protein was biosynthesized with different molecular weight; Brassica synthesized 35kD and 26kD protein, Raphanus with 40kD and 16kD and rice produced 320kD and 20kD protein at the 0.4% and over 0.6% concentration of NaCl respectively.

폐주물사를 혼입한 콘크리트의 내구특성에 관한 연구

박제선,윤경구,이주형,용석응 江原大學校 産業技術硏究所 1997 産業技術硏究 Vol.17 No.-

This study was conducted to evaluate durability of concrete which are increasingly demanded recently. Concrete durability properties incorporating waste foundry sand was performed with the variable of W/C ratio, Sand/Waste foundry sand ratio and Air entrainment-Non air entrainment. Cylinder specimens were made and subjected to freezing and thawing cycle at -18℃ and 4℃. Dynamic modulus of elasticity were as F/T cycle increase. The results show that decreasing W/C ratio and AE concrete makes improved resistance of freezing and thawing improved. Especially, resistance for freezing and thawing is improved by Fine aggregate/Waste foundry sand ratio which is 50%, 25%, 0% in a row.