초광대역 원형 슬롯 패치 안테나의 최적 설계

장준원,최경,황희용 강원대학교 정보통신연구소 2007 정보통신논문지 Vol.11 No.-

In this paper, an ultra wideband(UWB) circular slot antenna fed by tapered microstrip line is presented. The designed antenna is composed of a tapered feed line, a circular slot and a circular patch. Important physical parameters concerned with the wideband characteristic are investigated and optimized. The operational bandwidth of the antenna is from 3.5 GHz to 13.8 GHz. The simulated and the measured data show good agreement each other.

와인 잔 형태 슬롯-패치 UWB 안테나의 설계

장준원,황희용 강원대학교 정보통신연구소 2008 정보통신논문지 Vol.12 No.-

In this pafer, we proposed a wineglass slot-patch UWB antenna using approximately symmetry plane for prototype antenna of circular-slot UWB antenna. Using on field patterns, we show that the prototype circulat-slot UWB antenna operates on a series of multi-pole radiation based on TEn modes and the first resonant frequency by designed prototype antenna slot size. Ee designed and fabricated the wineglass slot-patch UWB antenna on FR4 substrate with t=1.524mm, εr=4.4 and tanδ=0.025, which not only has the half size of the original but also maintains UWB characteristics. The measured gain is reduced a little however radiation patterns are similar to that of the prototype antenna and maintain identical direction of max gain for all operation frequency.

초등학생의 전류에 대한 오개념을 줄이기 위한 비유물의 효과

장병기,이준희 춘천교육대학교 과학교육연구소 2000 과학교육연구 Vol.23 No.-

타원 패치-슬롯형 UWB 안테나의 해석

장준원,최경,황희용 江原大學校 産業技術硏究所 2007 産業技術硏究 Vol.27 No.B

In this paper, an modal analysis based on the distribution of the electromagnetic fields on the UWB elliptical patch-slot antenna is presented. We designed the UWB antenna by iterating the dimensional parameters of the antenna as the traditional design method. Then the antenna was carefully analyzed using 3D E-M simulator. The result of the analysis shows that the slot antenna operates on a series of the multi-pole radiations based on TE modes matched to the system impedance. This result gives us an easier method to design the similar antennas, which is the impedance matching to the system impedance after once constructing a proper structure with a series of multi-mode resonances.

한랭노출과 고혈압의 연관성

장태원,김윤규,윤동영,이창희,홍영습,신해림,정갑열,김준연 大韓産業醫學會 2001 대한직업환경의학회지 Vol.13 No.4

Objectives : This study was carried out to suggest preventive methods for hypertension in cold-exposed workers. Methods : In 11 refs·iteration industries, 68 workers working in refrigerated areas more than one time per day were selected as the exposed group, and 68 workers not exposed to cold were selected as the control group. We interviewed the subjects with a questionnaire covering occupational history, and conducted clinical and laboratory tests including measurements of blood pressure and core temperature. Results : The systolic blood pressure in the exposed group(130.0±13.3 mmHg) was significantly higher than that recorded In the control group(118.3±12.1 mmHg), as was the diastolic blood pressure in the exposed group(82.7±8.5 mmHg) versus the control group(77.4±8.7 mmHg). The core temperature in the exposed group(36.1±0.7℃) was significantly lower than that experienced in the control group (36.4±0.5℃). In logistic regression analysis, age, cold exposure severity and milk intake were significant variables, with odds ratios of 5.204(95 % CI 1.440∼18.812), 2.674(95 % CI 1.080∼6.618), and 0.364(95 % Cl 0.141∼0.942) , respectively. Conclusions : Our study suggests that cold-exposed workers have higher a higher risk of hypertension, and that their core temperature is lower. Risk factors affecting hyper-tension of cold-exposed workers include age, cold exposure severity and milk intake. For the prevention of hypertension, cold-exposed workers should minimize cold-exposure time as much as possible.

側方流動 低減을 위한 EPS工法의 適用性에 관한 硏究

장정욱,박춘식,안준희 국립7개대학공동논문집간행위원회 2005 공업기술연구 Vol.5 No.-

This study analyzed the reductive effect of lateral flow by the section and height of reinforcement of EPS. The conclusions of the study are as follws. (1) The lateral flow increased as the section of reinforcement decreased. The reinforcement section that satisfied the allowable range of the lateral flow turned out to be approximately 80% of the standard reinforcement section. (2) As reinforcement height was decreasing, the lateral flow increased. The reinforcement height that satisfied the allowable range of the lateral flow turned out to be approximately 50% of the total lateral height of abutment.

새열기형의 임상적 고찰

김장묵,김대식,백승혁,한동렬,김희중,백병준,오천환 순천향의학연구소 2000 Journal of Soonchunhyang Medical Science Vol.6 No.2

Background and Objectives : Branchial cleft anomalies are encountered rarely in clinical practice. We reviewed medical records of branchial cleft anomalies according to age and sex distribution, site distribution, characteristics of mass on physical examination, location of mass, preoperative diagnosis, type of branchial cleft cyst and report our experience with 25 cases of branchial cleft anomalies. Materials and Methods : A review of medical records was performed on 25 cases of branchial cleft anomalies diagnosed in pathologic report from January, 1990 to March, 2000. Result : Sex distribution was 11 male and 14 female, age distribution was most common in third decade which was 8 cases(32%). Site distribution was predominant in left side(13 cases), and in physical examination, the characteristics of the mass was nontender(76%), mobile(60%), soft(80%). The lesion site was submandibular area in 2 cases, upper 1/3 portion of sternocleidomastoid muscle(SCM) in 2 cases, middle 1/3 portion of SCM in 20 cases and parotid area in 1 case. The preoperative diagnosis was branchial cleft cyst in 16 cases, cervical lymphadenitis in 3 cases, tuberculous lymphadenitis in 3 cases, branchial cleft fistula in 1 case, dermoid cyst in 1 case and parotid mass in 1 case. Among 25 cases, first branchial cleft cyst was seen in 4 cases, second branchial cleft cyst in 20 cases and second branchial cleft fistula in 1 case. Conclusion : The clinical history of recurrent neck inflammatory episodes in young patients and nontender, mobile, soft neck mass should raise the suspicion of this entity. Investigation using CT scanning in combination with aspiration is useful. Treatment of all branchial cleft anomalies is complete surgical excision because there is lack of spontaneous regression, a high rate of recurrent infection, the possibility of other diagnosis, and rare malignant degeneration. Complete removal without complications depends on a good understanding of regional embryogenesis, a knowledge of the surrounding structure, and awareness of the different anatomical presentation.

광주지역 일부 남성의 연령과 배뇨량에 따른 최고요속 정상치

윤희철,박희수,노준,장대수 조선대학교 부설 의학연구소 2000 The Medical Journal of Chosun University Vol.25 No.1

Background and Objective : The Peak or maximum uroflow rate has been useful in screening test for the diagnosis of lower urinary tract dysfunction, and is used as a parameter in the diagnosis of lower urinary tract dysfunction, such as prostatism, urethral stricture, or neurogenic bladder, and the postoperative assessment of adequate surgery in urologic patients. We need a peak uroflow rate nomogram for the adjusted peak uroflow, because uroflow in normal healthy men depends on the voided volume and decreases with age. Materials and Methods : Peak flow rates and volumes voided were measured in 315 males who were free of voiding dysfunction, ranging in age from 10 to 80. To search for the equation of age, voided volume and peak uroflow, we used the least squares method for the equation providing least residual standard deviation by SPSS program. Results : The equation of age, volume voided and peak flow rate is Q=24.383+0.413A-0.006934A2-1164.644/V (Q: peak flow rate, A: Age, V: voided volume). Means of measured age, volumes voided, and peak flow rate was 45.7, 227.6ml, and 20.7ml/sec respectively. At this point, reference peak uroflow is 23.6m1/sec. Adjusted peak uroflow was obtained by subtracting the difference between the measured and expected peak uroflow from the reference peak uroflow. According to the equation Q, We designed nomogram with adjusted peak uroflow rate used. Conclusions : In our nomogram an adjusted peak flow rate <.8ml /sec(1.2 standard deviation) should be considered suspicious for lower urinary tract obstruction. This peak uroflow rate nomogram can be used clinically to evaluate lower urinary tract obstruction and its postoperative assessment.

Poly(acrylic acid)와 Poly(ethylene oxide)의 착체형성에 대한 용매와 온도의 영향

이장우,안희준 釜山大學校生産技術硏究所 1998 生産技術硏究所論文集 Vol.55 No.-

수소 결합을 통한 고분자 착체 형성에 있어서 용매의 종류와 온도의 영향을 조사하기 위하여 poly(acrylic acid)(PAA)와 poly(ethylene oxide)(PEO) 착세계에 대하여 용매는 순수 물 및 물-메탄올(30 wt%) 혼합 용매의 두 종류를 선택하여 이들 용매에서의 착체 형성거동의 차이를 모세관 점도계, 전위차계 및 UV 분광기를 사용하여 여러온도에서 조사하였다. 환원점도의 측정을 통하여 물에 메탄올을 첨가하면 최대 착체 형성점에 해당하는 반복단위 몰비가 [PEO]/[PAA]=1.2:1 부근에서 1.5:1로 이동함이 밝혀졌다. UV 측정에서 용액의 흡광도가 일정하게 되는 소위 "isobestic"점으로부터 이탈 현상은 착체 형성에 대한 용매효과를 다시 입증해 주었다. 그리고 여러 온도에서 pH 측정을 통하여 추정한 열역학적 성질들의 변화로부터 30℃이상의 고온에서는 혼합용매에서의 착체 형성 거동이 순수 용매의 경우에 비하여 더욱 불리해졌다. 이것은 물에서는 수소결합은 물론 소수성 상호작용도 착체 안정화에 큰 기여를 하나, 물-메탄올에서는 주로 수소결합만이 착체 형성에 관여하고 있기 때문이라 생각된다. To investigate the effects of solvent type and temperature on the interpolymer complexation via hydrogen bonding, a study was made on the complex system of poly(acrylic acid(PAA) and poly(ethylene oxide)(PEO) in two kinds of solvent systems, pure water and water-MeOH(30 wt%) mixed solvent, at various temperatures using the Ubbleohde viscometer, pH-meter and UV spectrophotometer. The repeating unit mole ratio at the most optimum complexation as confirmed by the reduced viscosity measurement was shifted from [PEO]/[PAA] 1.2:1 to 1.5:1 by the addition of methanol to water. From the UV measurement, the deviation from the "isobestic point" (where the absorbance of the solution remains constant) has presente another evidence for the solvent effect on complexation. In addition, the analysis of the changes in thermodynamic properties upon complexation as estimate from pH measurement at several temperatures reveals that the complex formation in mixed solvent became more unfavorable compared to that in pure solvent at high temperatures above 30℃. This could be explained by considering that in water the hydrophobic interaction as well as the hydrogen bonding may greatly contribute to the stabilization of the polymer complex formed, while in water-methanol the main stabilizing force would be the hydrogen bonding alone.

Neuropeptide γ의 구조 및 생리활성

구희정,서정길,김은희,허민도,정준기,박장수,강신원,박남규 부산대학교 유전공학연구소 1997 분자생물학 연구보 Vol.13 No.-

생리활성을 지닌 신경펩타이드의 구조와 활성간의 관계를 규명하기 위하여 고상법으로 합성한 세종류의 neuropeptide γ(mammalian-,trout- 그리고 goldfish-neuropeptide γ)를 사용하여 연구하였다. Circular dichroism spectra에 의하면 mammalian-,trout- 와 goldfish-neuropeptide γ는 완충액 조건하에 모두 random한 구조를 나타내었다. 중성 및 산성 지질 존재 하에서, mammalian-과 trout- neuropeptide γ는 여전히 random한 구조를 취하였다. 그러나, goldfish-neuropeptide γ는 중성 및 산성지질하에서 부분적으로 α-helix구조를 나타내었다. 장관 수축활성에 있어서는 carp 장관, guinea-pig 회장 그리고 rat십이지장에 대하여 비교하였다. Carp에 대해서는 goldfish-neuropeptide γ= trout- neuropeptide γ>mammalian-neuropeptide γ순으로 활서이 나타났다. 그러나, guinea-pig 회장과 rat십이지장에 대해서 mammalian-neuropeptide γ는 어류 유래성 neuropeptide g들 보다 높은 수축활성을 나타내었다. 이러한 결과들은 neuropeptide γ들이 종-특이적인 활성을 나타낸다는 것을 제시한다. The relationship between structure and biological activity was studied on the three neuropeptides(mammalian-,trout- and goldfish-neuropeptide γ)that were syntheized by the solid-phase method. Circular dichroism spectra showed that mammalian-,trout- and goldfish-neuropeptide γadopted an undered structure in buffer solution. In the presence od neutral and acidic liposomes, mammalian-and trout- neuropeptide γ also took a random structure. However, goldfish-neuropeptide γ took an α-helical structure in acidic liposomes. The intestinal motility response was investigated with carp interstines, guinea-pig ileums and rat duodenums. In case of carp intestine, contractine activity was as follows:goldfish-neuropeptide γ= trout- neuropeptide γ> mammalian-neuropeptide γ. On the other hand, the contracile activity of mammalian-neuropeptide γ was more potent than trout- and goldfish-neuropeptide γ in the guinea-pig ileums and rat duodenums. these results suggest that neuropeptide γs showed the species-specific activity.