• 한국지반환경공학회 논문집
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• 제10권4호
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• pp.41-48
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• 2009

표준사로 형성된 지반 10cm아래에 연성관을 매설하여 각각의 상대밀도에서 지반거동에 따른 관의 변형을 관찰을 하였다. 지반보강 상태에서의 관의 거동을 파악하기 위하여 지오그리드를 매설관 하부에 설치한 후 각각 지반에서의 관의 변형을 관찰하였다. 관아래 지오그리드를 설치한 후 보강된 지반의 관 변형형태를 관찰하였다. 지오그리드로 보강한 지반은 수직하중이 높아질수록 보강재에 인장력이 형성되어 보강유무에 따른 동일한 수직하중에서 침하가 감소하였다. 상대밀도 100%지반과 70%지반 변형분포가 차이가 나타났다. 보강 70%지반에서는 최종침하 100mm일 때 무보강 100%지반의 최종침하에서의 지반반력에 가깝게 수렴 하였다. 매설관의 하부 변형 형태에서도 무보강 100% 지반의 매설관 변형 형태와 유사한 것으로 보아 연약지반에서 지오그리드의 보강효과가 기대된다.

• Journal of Forest and Environmental Science
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• 제36권2호
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• pp.113-121
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• 2020

This study was carried out in degraded and non-degraded community forests (CF) in the Terai region of Kanchanpur district, Nepal. A total of 63 concentric sample plots each of 500 ㎡ was laid in the inventory for estimating above and below-ground biomass of forests by using systematic random sampling with a sampling intensity of 0.5%. Mallotus philippinensis and Shorea robusta were the most dominant species in degraded and non-degraded CF accounting Importance Value Index (I.V.I) of 97.16 and 178.49, respectively. Above-ground tree biomass carbon in degraded and non-degraded community forests was 74.64±16.34 t ha^-1 and 163.12±20.23 t ha^-1, respectively. Soil carbon sequestration in degraded and non-degraded community forests was 42.55±3.10 t ha^-1 and 54.21±3.59 t ha^-1, respectively. Hence, the estimated total carbon stock was 152.68±22.95 t ha^-1 and 301.08±27.07 t ha^-1 in degraded and non-degraded community forests, respectively. It was found that the carbon sequestration in the non-degraded community forest was 1.97 times higher than in the degraded community forest. CO₂ equivalent in degraded and non-degraded community forests was 553 t ha^-1 and 1105 t ha^-1, respectively. Statistical analysis showed a significant difference between degraded and non-degraded community forests in terms of its total biomass and carbon sequestration potential (p<0.05). Studies indicate that the community forest has huge potential and can reward economic benefits from carbon trading to benefit from the REDD⁺/CDM mechanism by promoting the sustainable conservation of community forests.

• 한국소음진동공학회논문집
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• 제22권4호
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• pp.352-357
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• 2012

The ground resonance instability of a helicopter with bearingless main rotor hub were investigated. The ground resonance instability is caused by an interaction between the blade lag motion and hub inplane motion. This instability occurs when the helicopter is on the ground and is important for soft-inplane rotors where the rotating lag mode frequency is less than the rotor rotational speed. For the analysis, the bearingless rotor was composed of blades, flexbeam, torque tube, damper, shear restrainer, and pitch links. The fuselage was modeled as a mass-damper-spring system having natural frequencies in roll and pitch motions. The rotor-fuselage coupling equations are derived in non-rotating frame to consider the rotor and fuselage equations in the same frame. The ground resonance instabilities for three cases where are without lead-lag damper and fuselage damping, with lead-lag damper and without fuselage damping, and finally with lead-lag damper and fuselage damping. There is no ground resonance instability in the only rotor-fuselage configuration with lead-lag damper and fuselage damping.

• Preventive Nutrition and Food Science
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• 제8권2호
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• pp.196-199
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• 2003

We investigated the antagonistic effects of two lactococcal bacteriocins, nisin or lacticin NK24, on the growth and the survival of Listeria monocytogenes in vacuum or modified atmosphere-packaged ground beef, Ground beef was inoculated with approximately 3 log colony-forming units (CFU) of L. monocytogenes ATCC 15313 culture per gram of ground beef. Inoculated samples were blended with/without 100 AU/g nisin or lacticin NK24, and subsequently vacuum or modified atmosphere packed at 4$^{\circ}C$. Listeria in the bacteriocin-treated and control samples was subsequently isolated from both vacuum and modified atmosphere packs and enumerated as CFU on Listeria Isolation Agar medium. Microbial counts in ground beef treated with bacteriocin declined steadily, while those of non-treated beef samples increased steadily. The results obtained demonstrate that nisin inhibits the growth of L. monocytogenes more effectively than lacticin NK24 at 100 AU/g. The use of lactococcal bacteriocins, such as nisin or lacticin NK24, in vacuum or modified atmosphere packaging offers a promising approach for eliminating or reducing the risk of L monocytogenes contamination in ground beef.

• 생물환경조절학회지
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• 제21권3호
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• pp.281-285
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• 2012

본 연구는 쌈채 및 강장제로 이용되고 있는 산마늘을 조경용 지피식물로 활용하고자 수행하였다. 차광 정도를 30%, 50%, 80%로 처리하여 생육 특성 및 엽록소 함량 등을 조사하였다. 엽수는 처리구별로 유의성이 인정되지 않았으나 엽장과 엽폭은 80% 차광 처리구가 각각 16.8cm, 10.1cm로 무처리구의 13.4cm, 7.3cm에 비해 우수하였다. 생체중은 무처리구가 차광 처리구에 비해 우수한 것으로 나타났으나 지상부 생체중은 무처기구가 8.5g인데 비해 80% 차광 처리구가 0.4g로 양호하였다. 엽록소 함량은 50% 차광 처리구가 42.8, 80% 차광 처리구가 40.5로 무처리의 36.7에 비해 높았다. 따라서 차광 수준에 따른 산마늘의 생육 특성은 80% 차광 처리구에서 가장 우수하여 음지성 지피식물로서 가치가 있는 것으로 나타났다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
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• pp.586-588
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• 2005

The MSC (Multi Spectral Camera) system is a remote sensing payload to obtain high resolution ground image. This system uses lossy image compression method for &Direct mission& that transmit whole image during one contact. But some image degradation occurred especially at high compression ratio. To reduce this degradation, the MSC uses NUC (Non-uniformity Correction) Unit. This unit correct CCD (Charge Coupled Device)'s high-frequency non-uniformity. So high frequency contents of image can be minimized and whole system SNR can be maximized. But NUC has some disadvantage either. It decreases entire system reliability by adding one electronic system. Adding NUC also led to difficulty of electronic design, assembly and testability. In this paper, the comparison is performed between on-orbit non-uniform correction and on ground correction. by evaluating NUC advantage for the point of view of image quality. Using real MSC parameter and proper model, considerable reference point for the system design came to possible.

• Korean Journal of Radiology
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• 제1권2호
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• pp.73-78
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• 2000

Objective: To describe the HRCT findings of cytomegalovirus (CMV) pneumonia in non-AIDS immunocompromised patients Materials and Methods: This retrospective study involved the ten all non-AIDS immunocompromised patients with biopsy-proven CMV pneumonia and without other pulmonary infection encountered at our Medical Center between January 1997 and May 1999. HRCT scans were retrospectively analysed by two chest radiologists and decisions regarding the findings were reached by consensus. Results: The most frequent CT pattern was ground-glass opacity, seen in all patients, with bilateral patchy (n = 8) and diffuse (n = 2) distribution. Other findings included poorly-defined small nodules (n = 9) and consolidation (n = 7). There was no zonal predominance. The small nodules, bilateral in eight cases and unilateral in one, were all located in the centrilobular region. Consolidation (n = 7), with patchy distribution, was bilateral in five of seven patients (71%). Pleural effusion and bilateral areas of thickened interlobular septa were seen in six patients (60%). Conclusion: CMV pneumonia in non-AIDS immunocompromised patients appears on HRCT scans as bilateral mixed areas of ground-glass opacity, poorly-defined centrilobular small nodules, and consolidation. Interlobular septal thickening and pleural effusion are frequently associated.

• 한국철도학회논문집
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• 제19권4호
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• pp.480-488
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• 2016

최근 철도주변의 개발이 확산되고 있는 가운데 비개착공법을 이용하여 철도노반하부를 횡단하는 구조물을 시공하는 경우가 불가피하게 증가하고 있다. 그러나 기존선 하부를 횡단하는 구조물을 시공하는 경우 구조물 주변의 지반응력이완에 대하여 설계 시 검토는 미비한 실정이다. 본 연구에서는 비개착공법 시공 시 구조물 주변지반의 응력이완에 대하여 실내토조실험을 통하여 지반의 응력이완 범위를 규명하였고, 지중경사계를 이용한 현장계측을 통하여 지반의 수평변위를 계측하였으며, 수치해석을 통하여 응력이완영역 및 선로지지강성을 분석하였다. 실내토조실험 결과 Rankine의 수평토압 영역과 유사한 파괴면이 생성되었으며, 지중경사계를 이용한 현장계측 결과, 강관의 압입 시기를 기준으로 급격하게 변위가 발생하였으며, 또한 수치해석 결과 해석된 수평토압이 Rankine의 수평토압에 가깝게 나타났으며, 비개착 구조물 주변 지반의 수직응력이 약 40% 감소함에 따라 노반지지강성이 크게 저하됨을 알 수 있었다. 이는 열차의 주행안정성 영향을 미쳐 탈선의 위험이 증가하므로 향후 기존선 하부를 통과하는 지하구조물 시공 시 구조물 주변의 보강이 반드시 필요할 것으로 판단된다.

• Journal of Forest and Environmental Science
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• 제35권4호
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• pp.248-257
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• 2019

We chose the Mt. Dalum area (located in Gijang-gun, Busan, Korea) for our survey, particularly The pine wilt disease zone and the non-permanent control area. This study investigates the effect of pine wilt disease on the distribution of beetle species in the process of ecosystem change due to insect control; pine forests treated for pine wilt disease were divided into insect control and non-control sites, respectively. The results of this study are as follows. Twen tyseven species belongs to 12 families were identified from 969 ground beetles collected from this sites. Species richness was the highest in Coleoptera (6 species, 469 individuals). In the control site, 21 species belongs to 10 families were identified from 228 individuals, while 24 species of 11 families from 533 individuals in the non-control area. The highest number of species were noted in June and July from the non- control and control sites, respectively. The highest number of insects in control and non-control sites was observed in July, while the lowest in September. Sipalinus gigas gigas, Spondylis buprestoides, Plesiophthalmus davidis, Calosoma maximowiczi, Damaster jankowskii jankowskii, and Damaster smaragdinus were captured in both study sites. Episomustur ntus and Glischrochilus ipsoides were only captured in the control site, while Macrodorcas rectus rectus and Pheropsophus javanus were only captured in the non-control site. Six beetles and five species (such as Calosoma maximowiczi) were found in the control site and six species (including Damaster smaragdinus) in the non-control site. The species distributions by altitude were 163, 518, and 258 individuals, at 100, 200 and 300 m sites, respectively. The diversity, evenness, and dominance indices in the control area were 0.764, 0.812, and 0.367, respectively. The diversity, evenness, and dominance indices in the non-control area were 0.927, 0.837, and 0.352, respectively. The similarity index between the control and non-control area was 80%.

• Journal of Chest Surgery
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• 제53권5호
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• pp.250-257
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• 2020

Background: Lung adenocarcinoma (LUAD) with ground-glass opacity (GGO) can become aggravated, but the reasons for this aggravation are not fully understood. The goal of this study was to analyze the genetic features and causes of progression of GGO LUAD. Methods: LUAD tumor samples and normal tissues were analyzed using an Illumina HiSeq 4000 system. After the tumor mutational burden (TMB) was calculated, the identified mutations were classified as those found only in GGO LUAD, those present only in nonGGO LUAD, and those common to both tissue types. Ten high-frequency genes were selected from each domain, after which protein interaction network analysis was conducted. Results: Overall, 227 mutations in GGO LUAD, 212 in non-GGO LUAD, and 48 that were common to both tumor types were found. The TMB was 8.8 in GGO and 7.8 in non-GGO samples. In GGO LUAD, mutations of FCGBP and SFTPA1 were identified. FOXQ1, IRF5, and MAGEC1 mutations were common to both types, and CDC27 and NOTCH4 mutations were identified in the non-GGO LUAD. Protein interaction network analysis indicated that IRF5 (common to both tissue types) and CDC27 (found in the non-GGO LUAD) had significant biological functions related to the cell cycle and proliferation. Conclusion: In conclusion, GGO LUAD exhibited a higher TMB than non-GGO LUAD. No clinically meaningful mutations were found to be specific to GGO LUAD, but mutations involved in the epithelial-mesenchymal transition or cell cycle were found in both tumor types and in non-GGO tissue alone. These findings could explain the non-invasiveness of GGO-type LUAD.