Foamex 매질을 이용한 이동통신 단말기용 듀얼밴드 플라스틱 칩 안테나 특성에 관한 연구

이영훈,Lee, Young-Hun 한국전기전자재료학회 2005 전기전자재료학회논문지 Vol.18 No.2

In this papers, we made study for plastic chip antenna, the plastic is Foamex with the circle of PVC and its electric characteristics are dielectric constant 1.9, insulation intensity 112 KV/cm. The proposed antenna is same as the conventional antennas are usually constructed with ceramic chip, which are not fragile in nature and don't tend to break easily. Therefore the proposed antenna with its advantage is attractive for application in mobile antenna. In order to valid the proposed papers, it is implemented the antennas of four types and experimented. From the results, we conformed that the antennas are operated at the dual band which is cellular band and Korea-PCS band. And the gain of the antennas has about above -2 dB and the pattern is same as conventional antennas. From this papers, the realized antennas using Foamex material will be application for mobile phone antenna.

21세기 통일시대에서의 위성의 역할

이영훈,오의교,Lee, Yeong-Hun,O, Ui-Gyo 한국위성정보통신학회 1997 위성통신과 우주산업 Vol.5 No.2ㆍ3

위성탑재용 안테나 설계기술에 관한 연구

이영훈,박한규,김은수,Lee, Yeong-Hun,Park, Han-Gyu,Kim, Eun-Su 한국위성정보통신학회 1994 위성통신과 우주산업 Vol.2 No.1

경동맥 내중막 두께 및 죽종과 심 혈관 질환 위험요인과의 관련성

이영훈,최련화,신민호,권순석,박경수,정슬기,정은경,최진수,Lee, Young-Hoon,Cui, Lian-Hua,Shin, Min-Ho,Kweon, Sun-Seog,Park, Kyeong-Soo,Jeong, Seul-Ki,Chung, Eun-Kyung,Choi, Jin-Su 대한예방의학회 2006 예방의학회지 Vol.39 No.6

Objectives : This study was conducted to examine the association between the carotid artery intima-media thickness (IMT), plaque and cardiovascular risk factors according to gender and age. Methods : The data used for this study were obtained from 1,507 subjects (691 men, 816 women), aged 20-74 years, who participated in 'Prevalence study of thyroid diseases' in two counties of Jeollanam-do Province during July and August of 2004. The body mass index (BMI) and waist hip ratio (WHR) were calculated by anthropometry The blood pressure, pulse rate, pulse pressure, total cholesterol, triglyceride, HDL cholesterol and fasting blood sugar level were also measured. Ultrasonography was used to measure the carotid artery IMT and plaque. IMT measurements were performed at 6 sites, including both common carotid arteries, and the bulb and internal carotid arteries. The definition of the 'mean IMT' was mean value obtained from these 6 sites. Results : The ${\pm}$ standard deviation IMT values were $0.65{\pm}0.14\;and\;0.60{\pm}0.13mm$ in men and women (p<0.001), respectively. The data were analyzed according to gender and the 50 year age groups. In a multiple linear regression analysis, age and hypertension were positively associated with the mean IMT in both men and women, aged<50 years. Age, total cholesterol and smoking (current) were positively associated with the mean IMT in men $(\geq50\;years)$. Age was positively associated with the mean IMT in women $(\geq50\;years)$, but the HDL cholesterol level was negatively associated. The prevalence of plaques was 44.2%(196/443) in men and 19.4%(89/459) in women, for those greater than 50 years of age. In a multiple logistic regression analysis, age (OR=1.090, 95%CI=1.053-1.129), HDL cholesterol (OR=0.964, 95%CI=0.944-0.984), total cholesterol (OR=1.009, 95%CI=1.002-1.017)and BMI (OH=0.896, 95%CI=0.818-0.983) were independently associated with plaques in men; whereas, age (OR=1.057, 95%CI=1.012-1.103), HDL cholesterol (OR=0.959, 95%CI=0.932-0.986), pulse pressure (OR=1.029, 95%CI=1.007-1.050) and triglycerides (OR=0.531, 95%CI=0.300-0.941) were independently associated with plaques in women. Conclusions: There were significant gender and aging differences in the association between the IMT, plaque and cardiovascular risk factors. Therefore, for the prevention of atherosclerosis, selective approaches should be considered with regard to gender and age factors.

혈압 수준과 경동맥 내중막 두께 및 동맥경화반의 관련성

이영훈,권순석,최진수,이정애,최성우,류소연,신민호,Lee, Young-Hoon,Kweon, Sun-Seog,Choi, Jin-Su,Rhee, Jung-Ae,Choi, Sung-Woo,Ryu, So-Yeon,Shin, Min-Ho 대한예방의학회 2009 예방의학회지 Vol.42 No.5

Objectives : The aim of this study was to investigate the association of blood pressure levels with the common carotid artery intima-media thickness (CCA-IMT) and carotid plaques. Methods : Data were obtained from 2,635 subjects, aged 50 years and over, who participated in the Community Health Survey (a population-based, cross-sectional study) in Dong-gu, Gwangju city between 2007 and 2008. Participants were categorized into three groups according to blood pressure levels; normotensives (<120/80 mmHg), prehypertensives (120-139/80-89 mmHg), and hypertensives ($\geq$140/90 mmHg). Prehypertensives were further categorized as low prehypertensives (120-129/80-84 mmHg) and high prehypertensives (130-139/85-89 mmHg). Carotid intima-media thickness and plaques were evaluated with a high-resolution B-mode ultrasound. Statistical analyses were performed using chi-square test, ANOVA, and multiple logistic regression. Results : Prehypertensives had significantly greater maximal CCA-IMT values than normotensives, with a multivariate adjusted odds ratio of 1.78 (95% CI=1.36-2.32) for abnormal CCA-IMT (maximal CCA-IMT$\geq$1.0 mm), and 1.45 (95% CI=1.19-1.77) for carotid plaques. The multivariate adjusted odds ratio of low prehypertensives was 1.64 (95% CI=1.21-2.21) for abnormal CCA-IMT, and 1.30 (95% CI=1.04-1.63) for carotid plaques compared with normotensives. Subject with hypertension had higher frequency of abnormal CCA-IMT (odds ratio, 2.18; 95% CI=1.49-3.18), and carotid plaques (odds ratio, 1.98; 95% CI=1.46-2.67) compared with normotensives after adjustment for other cardiovascular risk factors. Conclusions : Our results indicate that there is a significant increase in the prevalence of carotid atherosclerosis in subjects with prehypertension (even in low prehypertensives) compared with normotensive subjects. Further studies are required to confirm the benefits and role of carotid ultrasonography in persons with prehypertension.

몬테카를로 시뮬레이션을 이용한 휴대용 의료기기 누적공차분석에 대한 사례연구

이영훈,문덕희,Lee, Young Hoon,Moon, Dug Hee 한국시뮬레이션학회 2016 한국시뮬레이션학회 논문지 Vol.25 No.2

Tolerances are defined as the allowable variations in the geometry and positioning of parts in a mechanical assembly for assuring its proper functionality. Tolerance analysis is the activity related to estimating the potential accumulated variation in assemblies. If the estimated variances go out of the specified ranges, it causes the quality problem. Thus, we should adjust the tolerances and this activity is called as tolerance design. In this paper, a case study on the accumulated tolerance analysis and design using Monte Carlo simulation is introduced, which is applied for developing a portable medical device. Using the simulation study, we can improve the assemblability and functionality of the product. 공차란 각 부품들이 기구적으로 조립되었을 때 원하는 수준의 기능성을 확보할 수 있도록 각 부품의 기하학적 형상이나 위치에 대해 허용하는 치수의 변동량을 의미한다. 또한 공차해석이란 부품들이 조립되었을 때, 각 부품의 공차가 조립품에서 어떻게 누적되어 미치는 영향을 분석하는 일련의 절차를 의미한다. 만일 누적된 공차의 분산이 규정된 일정 수준의 범위를 벗어나면 조립품의 품질에 문제가 발생하기 때문에 당초 설정한 부품의 공차를 수정해야 하며, 이러한 과정을 공차설계라고 한다. 이 논문에서는 휴대용 의료기기의 설계단계에서 공차해석과 공차설계를 위해 몬테카를로 시뮬레이션 기법을 활용한 사례를 소개한다. 이러한 시뮬레이션 연구를 통하여 제품의 조립성과 기능성을 개선시킬 수 있다.

고 Mn 강 주강품의 내마모성에 미치는 Ni 첨가의 영향에 관한 연구

이영훈,천병욱,김성한,최창옥 ( Young Hun Lee,Byung Wook Cheon,Sung Han Kim,Chang Ock Choi ) 한국주조공학회 1992 한국주조공학회지 Vol.12 No.2

N/A This study has been performed in increase the wear resistance characteristic and the mechanical properties of high Mn steel castings with an addition of Ni to 1∼4% range. The initial structure of plastic cememtite has been possible to transform perfect austenite with watertoughening treatment. Increasing Ni content, the most wear loss has shown that ore has crushed until 100㎏ and decreased with increasing ore amount at ascast, the similar tendency has shown at heat treatment. Chang of hardness has shown high values that ore has been crushed until 300㎏, both as cast and treatment added 2%Ni.

한우태자의 기관연골 발생에 관한 형태학적 연구

이영훈,김인식,양홍현,백영기,Lee, Young-hoon,Kim, In-shik,Yang, Hong-hyun,Paik, Young-ki 대한수의학회 1997 大韓獸醫學會誌 Vol.37 No.1

This study was undertaken to obtain basic data on the histological changes in the tracheal cartilage of the embryos and fetuses of the Korean native cattle. Twenty-two embryos and fetuses of the Korean native cattle, ranging from 30mm(peesumptive fetal age 44 days) to 440mm(presumptive fetal age 168 days) in crown-nump(C-R) length, were used for present study. The results were summerized an follows; 1. Mesenchymal cells differentiated as chondroblasts were condensed into tracheal cartilage in the CRL 30mm of the Korean native cattle embryo, and the chondrocytes begun to appear in the tracheal cartilage in the CRL 40mm fetus. 2. The tracheal cartilage in the CRL 70mm fetus was composed of the large number of chondrocytes. The histochemi8cal reactions for glycosaminoglycans showed strong positive reaction in the CRL 380mm, and for collagen substance showed mildly in the 6th experimental group.

Formax 매질을 이용한 이동통신 단말기용 삼중대역 플라스틱 칩 안테나에 관한 연구

이영훈,송성해,Lee, Young-Hun,Song, Sung-Hae 한국정보통신학회 2007 한국정보통신학회논문지 Vol.11 No.12

본 논문은 휴대 단말기에 적용할 수 있는 삼중대역(Triple-band) 프라스틱 칩 안테나에 관하여 연구하였다. 프라스틱 칩은 PVC(Polyvilyl chloride)계열의 Foamex 매질을 사용하였으며, 전기적인 특성은 유전율이 1.9이고, 절연밀도는 112KV/cm이다. 프라스틱 칩 안테나는 세라믹 칩 안테나보다 잘 파손되지 않고, 이득과 효율이 좋은 장점을 가지고 있다. 본 논문에서는 4종류의 삼중대역 프라스틱 칩 안테나를 제작하고 실험하였다. 실험 결과 삼중대역에서 공진하였고, 안테나 이득은-2dB이상이고, 안테나 패턴은 일반적인 칩 안테나와 비슷한 전 방향 특성을 갖는다. 따라서 Foamex 매질을 이용하여 구현된 안테나는 삼중대역용 휴대폰과 다양한 무선통신시스템에 적용될 수 있다. In this paper, triple-band plastic chip antennas for mobile terminal are investigated. Plastic chip antenna is composed of Foamex material with circle of PVC(Polyvilyl chloride). For its electric characteristics, the dielectric constant is 1.9, the insulation intensity is 112KV/cm. Plastic chip antennas are don't tend to break easily against to external shock, have more gain and efficiency than ceramic chip antennas. Triple-band plastic chip antennas of four type are implemented and experimented. From the experiments results, the antenna resonate at the triple-band, the gain of the antennas has about above -2dB, the pattern is ommidirectional the same as the conventional antennas. So, the antennas realized with Foamex material will be application for mobile phone antenna operated at the triple band which is cellular band and Korea-PCS band and ISM band or the antenna for other wireless communication system.

포도와 오이즙액을 이용한 동충하초(Paecilomyces japonica) 균사체 배양액의 피부 주름개선효과

이영훈,최우식,박기훈,최영주,갈상완,Lee Young-Hoon,Choi U-Sic,Park Ki-Hoon,Choi Young-Ju,Gal Sang-Wan 한국생명과학회 2006 생명과학회지 Vol.16 No.3

포도와 오이즙액에 동충하초 균사체 배양액을 화장품으로서의 이용가능성을 조사하였다. 콜라겐 생성촉진 효과에서는 사람의 섬유아세포에서 시험물질 $0.1{\sim}0.5%$ 농도에서 콜라겐 생합성을 증가시키는 것을 관찰하여 동충하초 균사체 배양액은 적절한 농도에서 세포내 콜라겐 생성을 증가시키는 것으로 판단하였다. 포도와 오이즙액에 동충하초 균사체 배양액의 항산화효과에서는 항산화제인 Vit. C와 함께 SOD 활성능을 측정한 결과 동충하초 균사체 배양액이 0.01% 부터 1.0% 범위에서 농도의존적으로 SOD 활성을 증가시켜 0.1% 에서는 약 50% 정도 1.0% 에서는 90% 정도의 슈퍼옥사이드 라디칼을 소거시키는 것으로 나타났다. 항 혈액응고제로 알려진 퀘르세틴의 함량증가에서는 최초 포도와 오이즙액보다 배양 후의 농도가 약 15배 이상 증가하여 피부의 항 혈액응고에도 효과가 있을 것으로 판단되며, 이를 인체에 대한 자극시험을 실시한 결과 30명의 피검자 모두에게서 피부자극이 전혀 일어나지 않음을 확인하여 인체에 무해한 것으로 판단되었다. 따라서 포도와 오이즙액에 동충하초 균사체 배양액은 피부에 대한 부작용이 전혀 없으며 주름개선효과 및 항산화 활성을 갖는 기능성 화장재료로서의 이용 가치가 매우 높을 것으로 사료된다. The possibility of usage as cosmetic resource of the mycelial culture broth of P. japonica in the mixture of cucumber and grape extracts was investigated. In the effect of collagen synthesis promotion in human fibroblast cells, the culture broth of P. japonica of 0.1, 0.5 and 1.0% concentration increased the amount of collagen synthesis than that of control cells. The culture broth increased the SOD activity in the concentration dependant manner of 0.01% to 1.0% in the antioxydation activity test. About 90% of superoxide radical was eliminated by 0.5% concentration of the culture supernatant in the antioxydation test. Anticoagulant quercetin in the course of mycelial growth in the mixture of cucumber and grape extract was accumulated to 15 folds than that of pre-culture. In the skin safety test of the culture broth, there is no any skin damage signal in the tested 30 people. Taken together, we concluded that the culture broth of P. japonica in the mixture of grape and cucumber extracts can be used as a cosmetic resource.