• Journal of Korean Society of Rural Planning
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• v.16 no.1
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• pp.63-71
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• 2010

지난 수십 년 동안 형태지수는 패치의 복잡성을 정량화하여 생물종 다양성 보존과 같은 경관생태계획에 활용되어 왔다. 지역계획 연구자들이나 정책결정자들에게 경관구조와 패턴을 정량화하는 경관생태지수는 대상지역을 모니터링할 수 있는 하나의 수단으로 활용되어 왔다. 그러나 경관생태지수관련 연구를 살펴보면 연구 목적 및 범위에 따라 활용하는 경관생태지수의 종류가 매우 다양하고 복잡한 것을 알 수 있다. 또한 연구목적에 적합한 경관생태지수를 선정하는 것은 복잡한 수학분석과 함께 많은 주의가 필요한 것을 알 수 있다. 따라서 본 연구에서는 형태지수들을 도시지역, 도시외곽지역, 농촌지역 그리고 산림지역 등 4군데 사례지역에 적용하여 그 결과를 통해 형태지수들의 특성을 살펴보았다. 그 결과, 평균형태지수값(MSI)에서는 도시외곽지역이 가장 높게 나타났고, 평균프랙텔차원지수(MPFD)에서는 농촌지역이 높게 나타났다. 넓은 면적을 가진 패치에 가중점을 고려한 평균형태지수값(AWMSI)과 평균프랙텔차원지수값(AWMPFD)에서는 산림지역이 가장 높게 나타났다. 사용한 네 가지 형태지수값의 순위가 4군데 사례지역에서 다르게 나타났다. 특히 둘레와 면적의 로그전환을 이용하고 있는 프랙텔차원지수들의 경우, 도시와 도시외곽지역의 MPFD값은 같고, 도시외곽지역, 농촌지역과 산림지역의 AWMPFD값 차이는 적어 순위 분별력이 떨어졌다. 따라서 넓은 면적을 가진 패치에 가중점을 고려한 평균형태지수(AWMSI)가 지역별 산림패치의 복잡성을 잘 정량화할 수 있음을 본 연구결과에서 보여주고 있다.

• Journal of Chest Surgery
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• v.19 no.1
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• pp.25-34
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• 1986

Recently, radionuclide angiocardiogram is one of the most common procedure for assessment of ventricular performance due to its distinctive advantages such as safety, accuracy, and ease of repeated studies. Also, measurement and comparison between pre and postoperative left ventricular ejection fraction [LVEF] are meaningful for assessing the severity of myocardial damage which occurred during open heart surgery and the status of myocardial recovery. We obtained pre and post operative LVEF using radionuclide angiocardiogram on 30 patients composed of atrial septal defect, ventricular septal defect, cyanotic congenital heart disease, and valvular heart disease who undergone the open heart surgery from March to august 1984. The study revealed that ventricular septal defect and mitral valvular heart disease showed 8.1% and 6.2% decreases of postoperative LVEF, respectively. But, there are little increases of postoperative LVEF in the atrial septal defect and cyanotic congenital heart disease. In ventricular septal defect, each group of Qp/Qs over 2.0 and systolic pulmonary artery pressure over 50mmHg showed significant 17% and 14.7% decreases of postoperative LVEF, respectively. Considering the duration of the aortic cross clamping times and closing methods of VSD, each group of duration over 30 min. and of patch closure showed 13.9% and 14.2% decreases of LVEF between pre and postoperative status respectively which was significant finding statistically.

• Journal of electromagnetic engineering and science
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• v.19 no.1
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• pp.20-30
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• 2019

A wide-band multiple-input multiple-output (MIMO) antenna with dual-band (2.4 and 5 GHz) operation is proposed for premium indoor access points (IAPs). Typically, an omni-directional pattern is used for dipole antennas and a directional radiation pattern is used for patch antennas. In this paper, both antenna types were used to compare their performance with that of the proposed $2{\times}2$ MIMO antenna. We simulated and measured the performance of the MIMO antenna, including the isolation, envelope correlation coefficient (ECC), mean effective gain (MEG) for the IAPs, and the throughput, in order to determine its communication quality. The performance of the antennas was analyzed according to the ECC and MEG. The proposed antenna has sufficient performance and excellent characteristics, making it suitable for IAPs. We analyzed the communication performance of wireless networks using the throughput data of a typical office environment. The network throughput of an 802.11n device was used for the comparison and was conducted according to the antenna type. The results showed that the values of the ECC, MEG, and the throughput have unique characteristics in terms of their directivity, antenna gains, isolation, etc. This paper also discusses the communication performance of various aspects of MIMO in multipath situations.

• Child Health Nursing Research
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• v.28 no.1
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• pp.62-69
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• 2022

Purpose: This study explored the validity of a new type of thermometer and parent satisfaction with the new device. This 24-hour continuous monitoring smart wearable wireless thermometer (TempTraq^®) uses a very small semiconductor sensor with a thin patch-like shape. Methods: We obtained 397 sets of TempTraq^® axillary temperatures and tympanic temperatures from 44 pediatric patients. Agreement between the axillary and tympanic measurements, as well as the validity of the TempTraq^® axillary temperatures, were evaluated. Satisfaction surveys were completed by 41 caregivers after the measurements. Results: The TempTraq^® axillary temperatures demonstrated a strong positive correlation with the tympanic temperatures. The Bland-Altman plot and analysis of TempTraq^® axillary temperatures and tympanic temperatures showed that the mean difference was +0.45 ℃, the 95% limits of agreement were -0.57 to +1.46 ℃. Based on a tympanic temperature of 38 ℃, the results of validity of fever detection were sensitivity 0.85 and specificity 0.86. Satisfaction scores for TempTraq^® temperature measurement were all > 4 points (satisfactory). Conclusion: TempTraq^® smart axillary temperature measurement is an appropriate method for measuring children's temperatures since it was highly correlated to tympanic temperatures, had a reliable level of sensitivity and specificity, and could be used safely and conveniently.

• Clinical and Experimental Pediatrics
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• v.49 no.6
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• pp.635-642
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• 2006

Purpose : The purpose of this study is to determine whether the new pulmonary valve reconstruction technique prevents short-term postoperative pulmonary regurgitation and improves early and mid-term clinical outcome. Methods : We reviewed postoperative echocardiographic variables and chest X-ray films from 31 patients who had undergone valve reconstruction(pulmonary valve reconstruction group : PVR) for the repair of TOF between April 2000 and August 2004. We compared the clinical data of these patients with those from 47 patients who had right ventricular outflow tract reconstruction with a monocusp valve(monocusp ventricular outflow patch group : MVOP) and 22 patients who had a transannular patch repair without a monocusp valve(transannular patch group : TAP). Results : In the PVR group, 25 patients(81 percent) had trivial or mild pulmonary regurgitation in their early post operative echocardiogram. Only 12 patients(26 percent) in the MVOP group had mild pulmonary regurgitation; and no patient in the TAP group had it. Pulmonary valve function was good in 96 percent of the PVR group, 36 percent of the MVOP group, and none in the TAP group in early post-operative echocardiogram. Follow-up echocardiogram(1, 2, 3, 4 years later) of the MVOP and TAP groups showed moderate pulmonary regurgitation and severely decreased valve function in almost all cases. However, in the PVR group 54 percent(16/28), 50 percent(14/28), 37 percent(9/24), and 31 percent(5/16) of the patients had trivial or mild pulmonary regurgitation 1, 2, 3 and 4 years after operation, respectively. The valve function remained good in 80 percent(24/30), 64 percent(18/28), 57 percent(12/21), and 31 percent(5/16) of the patients 1, 2, 3 and 4 years after operation respectively. Conclusion : Pulmonary valve reconstruction is effective in reducing pulmonary regurgitation and right ventricular dilatation in the repair of TOF, even though regurgitation increases with time. Further study is needed to determine long-term results.

• Journal of Chest Surgery
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• v.36 no.2
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• pp.63-72
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• 2003

Although a variety of synthetic vascular grafts are available in modern vascular surgery, no ideal prosthesis ha,4 yet been developed. Small-caliber vascular grafts with low flow, as used in the lower extremity, continue to become thrombosed at unacceptable rates. We have developed and evaluated the new antithrombogenic blood contacting surfaces in canine model. Material and Method: Two now antithrombogenic blood contacting surfaces(Polyvinylalcohol -Polyurethane(PVA-PU) blend and natural Graphite-polyurethane(G-PU) blend) have been developed and evaluated in canine model, using vascular grafts and patches. The luminal surfaces of the test vascular grafts(5 mm ID) were fabricated by dipping a glass rod in PVA-PU blend solution(50 % PVA) using phase separation method. Mongrel dogs of either sex weighing 18-22 kg were anesthetized by endotracheal intubation using halothane and their lungs were ventilated with a volume-cycled ventilator, Maintenance anesthesia with 0.5-1.0% halothane and supplemental oxygen was used. Two pairs were used for comparison in the bilateral femoral arteries for both vascular grafts(PVA-PU vs. PU) and vascular patches(G-PU vs. PU). Bilateral groin incisions were made and the arteries were exposed and clamped. After an excision of 1 cm of the artery between clamps, a grail of 2.5 cm in length was implanted end-to-end using 6-0 polypropylene suture. The vascular patch was implanted as a form of on-lay patch. Animals were sacrificed at 1, 2, 4, 6, 8 and 16 weeks for vascular grafts and 1, 2. 4 and 6 weeks for vascular patches. Result The vascular grafts of PVA-PU blends showed patent lumina in the 2 and 16 weeks animals, while those of PU showed a patent lumen in 2 weeks animal. PVA-PU graft of 16 weeks showed a fairly clean luminal surface. A light microscopic finding of this graft demonstrated good tissue infiltration through porosity, The animals with vascular patches showed patent arteries in both groups except 2 weeks animal. Scanning electron microscopy of the luminal surfaces of G-PU patches in 4 and 6 weeks animals showed endothelial cell covering with microvilli. PU patches showed qualitatively less endothelial cell covering. Conclusion: In conclusion, PVA-PU and G-PU blends can be a promising blood contacting surfaces for application in a synthetic vascualr graft. However, further animal study is needed to determine the real long-term effects of these methods of surface modifications.

• Korean Journal of Environment and Ecology
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• v.19 no.4
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• pp.367-374
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• 2005

This study was conducted to comprehend the breeding bird community of thirteen urban forests ranged in size from $0.63{\~}37.0$ ha and compare the species richness of streetscapes such as wooded streets, street trees, and green patches. In urban forests, among thirty-one species observed, two species of Pica pica and Parus major were observed in all study areas, but five species of Phoenicuros auroreus, Pericrocotus divaricatus, Eurystomus orientalis, Emberiza elegans, and Cettia squameiceps were observed only one areas. Number of species was high at urban forests of Manchon, Bonri and Chimsan parks distributed in peripheral area of city, that was low at urban forests Jungri, Igoksaengsu and Sinam parks located in the center area of city. We observed the nests at wooded streets and green patches, did not find at street trees. Number of species and density were significantly high at wooded streets than at street trees. Number of species was highly correlated with the area of forests, and srecies richness of bush-nesting guild was low. As the area of urban forests increase, species richness of bush-nesting and -foraging guild showed the relative low rate of increase than other nesting guild. Our results indicate that bush-nesting and -foraging guild of birds was not being provided with their good habitat at urban forests in Daegu city Among streetscapes, birds preferred to u9e the wooded streets and green patch as habitat and pathway in urban ecosystem.

• Journal of Life Science
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• v.24 no.4
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• pp.437-446
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• 2014

Problems appear when triptans are taken orally. For example, the bioavailability of triptan is reduced by the digestive system, and the drug level in the blood reduces rapidly over time; there is also a possibility of gastrointestinal disorder. To improve side effects, a transdermal patch has been prepared in hydrogel form. The polymer matrix that makes up the hydrogel uses PVA; PEG is used as an additive to induce inter/intra hydrogen bonding of the PVA and almotriptan drug is added. In addition, to accelerate micro-phase separation between PVA chains, liquid nitrogen is used. In FT-IR analysis, the absorption bands of PVA, PEG, and almotriptan were found. The degree of crystallinity, the water uptake ability and tensile strength were increased with increasing PEG content. In drug release tests, the amount of drug released increased depending on the PEG content. In this study, hydrogels with 10 wt% PEG showed better performance in drug release. Approximately 60% of the total drug amount was released in 2 hr, and the drug continued to release for 1 day. Thus, the prepared hydrogel patch is suitable as a transdermal formulation for the second dose administration of triptans to patients who require recurrent migraine treatment within 24 hr after the first administration.

• Korean Journal of Plant Resources
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• v.25 no.4
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• pp.407-415
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• 2012

Pinus pumila, which occurs in the northeast Asia, is found limitedly in Daecheongbong area of Mt. Seorak in the South Korea. This population was chosen to study spatial pattern, genetic diversity and spatial genetic structure. There were 48 polymorphic and 30 monomorphic I-SSR markers. A total of 65 individuals which distributed in the study site (40 m ${\times}$ 70 m) showed weakly aggregate distribution (Aggregate Index = 0.871). A total of 40 genets were observed from 65 individuals through I-SSR genotype comparison. Proportion of distinguishable genotype (G/N), genotype diversity (D) and genotype evenness (E) were 61.5%, 0.977 and 0.909, respectively. In spite of the small number and the limited distribution, Shannon's diversity index (I = 0.567) was relatively high as compared with those of other plant species. Spatial autocorrelation using Tanimoto's distance showed that the genetic patch was established within 12 m. Based on Mantel tests, there was relatively low correlation between genetic distance and geographic distance. Therefore, it seems the P. pumila population was formed by many parent trees in early stage. For ex situ genetic conservation of P. pumila, the sampling strategy is efficient at least above 12 m between individual trees.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.30 no.1
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• pp.45-53
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• 2019

In this paper, three types of array antennas for 5G mobile devices operating at 28 GHz were designed, and their performances were compared. The isolation between antenna elements was compared based on $S_{21}$. The $S_{21}$ of dipole, slot, and patch type are -13.76 dB, -16.88 dB, and -11.47 dB, respectively, with the slot-type antenna having the highest isolation. In order to compare the beam coverage performance, several characteristics such as beam width and maximum beam steering angle were analyzed. The analysis shows that the slot type has the widest steering angle of $63^{\circ}$ while the patch type has narrowest with $36^{\circ}$. In addition, to verify the performance of the antennas in the actual usage environment of the device, antenna characteristics in talk mode and data mode were analyzed through simulation. The results confirmed that the slot-type array antenna is the most suitable array antenna element for 28 GHz 5G mobile devices.