• Journal of the Korea institute for structural maintenance and inspection
• /
• v.18 no.4
• /
• pp.118-125
• /
• 2014

As the earth's current global warming has caused elevation of sea water temperature, size of storms is foreseen to increase and consequently large damages on port facilities are to be expected. In addition, due to the improved processing efficiency of port cargo volume and increasing necessity for construction of eco-friendly port, demands for various forms of port facilities are anticipated. In this study, two kinds of nondestructive evaluation (NDE) techniques (rebound hardness and ultrasonic pulse velocity methods) are investigated for the effective maintenance of smart green harbor system. A new methodology to estimate the underwater concrete strengths is proposed and its feasibility is verified throughout a series of experimental works.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.33 no.2
• /
• pp.433-442
• /
• 2013

This paper presents experimental research work for the evaluation of one-dimensional and two-dimensional acoustic source locations with 50m length of a precast prestressed concrete box girder. Acoustic events are generated by the impacts of Schmidt Hammer and the impact signals are detected by acoustic emission sensors mounted on the concrete web surface of PSC box girder with the average spacing of 9.34m. Based on the amplitude of detected acoustic signals, considering the noises developed in PSC box girder bridges, the arrival times of acoustic signals are estimated by the first arrival times of 0Volt, 0.5Volt, and 1.0Volt amplitude in each signal. Using Least Square Method, the velocities and the source locations of acoustic signals are evaluated. Based on the test results, the spacing of AE sensors and the AE sensor networks are discussed to reduce the source location errors.

• Journal of the Korea Concrete Institute
• /
• v.14 no.1
• /
• pp.1-7
• /
• 2002

The purpose of this research is to obtain a practical expression for the estimation of compressive strength of concrete using non-destructive testing method such as rebound Schmidt hammer and ultrasonic pulse

• Journal of the Korean Institute of Gas
• /
• v.12 no.2
• /
• pp.77-84
• /
• 2008

Experimental study was conducted to clarify the importance of buoyancy effects in laminar lifted flames which have been well understood by cold jet similarity theory. To evaluate buoyancy effects, lifted flame behaviors were systematically observed in methane and propane lifted flames diluted with He as changing the fuel nozzle diameter from 0.1 to 6 mm. Important physical parameters such as fuel strength, flame stretch and flame curvature, which were derived through simple physical scaling laws, were estimated. It is experimentally proven that buoyancy effects are important in relatively large fuel nozzle diameter and large fuel dilution with He. The results of Chen et al., which displayed the existence of stably lifted flames for 0.5

• Proceedings of the Plant Resources Society of Korea Conference
• /
• 2022.09a
• /
• pp.61-61
• /
• 2022

섬괴불나무(Lonicera insularis Nakai)는 인동과(Caprifoliaceae) 인동속(Lonicera) 식물로 우리나라 울릉도에 제한적으로 분포한다. 인동과 식물 중 인동(L. japonica Thunb.), 괴불나무[L. maackii (Rupr.) Maxim] 등 다수의 분류군이 약리효능이 입증되었으며, 맛이 뛰어나 차, 술, 음료 등으로 다양하게 활용되고 있다. 그 중 섬괴불나무는 최근 면역자극 및 항비만 활성 등 다양한 약효가 확인되어 약용자원으로서의 잠재적 가치가 큰 것으로 보고된 바 있다. 따라서 본 연구를 통해 특산식물인 섬괴불나무의 적정 자생지를 명확하게 구명하여 보전생물학적 연구, 재배 및 산업화와 같은 현지 외 보전연구를 위한 기초자료로 활용하고자 한다. 연구 결과, 울릉도에서 확인된 섬괴불나무의 주요 분포지는 4개소로 해안도로 일대에 자생하고 있었다. 입지환경은 해발고도 8-20 m, 사면 방위는 남사면, 경사는 15-30°로 완경사지에서 주로 자생하고 있었다. 방형구(10×10 m) 내 개체수는 5-25 개체로 대부분 군락을 이루고 있는 것으로 확인되었다. 4개 조사구에 대한 군집분석을 실시한 결과, 조사구는 곰솔 군집(Pinus thunbergii Parl.)으로 상층의 발달이 거의 없는 전형적인 해안 식생의 구조로 확인되었다. 관목층은 보리장나무(Elaeagnus glabra Thunb.), 송악[Hedera rhombea (Miq.) Bean], 머루(Vitis coignetiae Pulliat ex Planch.) 등이 경쟁관계에 있었으며, 초본층은 왕호장근[Reynoutria sachalinensis (F.Schmidt) Nakai], 갯메꽃[Calystegia soldanella (L.) R.Br], 해국(Aster spathulifolius Maxim.) 등으로 인하여 섬괴불나무는 피압된 것으로 판단된다. 군집의 안전성, 다양성을 나타내는 척도인 종다양성지수는 1.259, 최대종다양성지수는 1.286, 균재도는 0.979, 우점도는 0.021로 확인되었다.

• Journal of Life Science
• /
• v.25 no.1
• /
• pp.101-112
• /
• 2015

A type of cell junction that is formed between different parts within the same cell is called autotypic cell junction. Autotypic junction proteins form tight junctions found between membrane lamellae of a cell, especially in myelinating glial cells. Some of them have postsynaptic density-95/disks large/zonula occludens-1 (PDZ) domains, which interact with the carboxyl (C)-terminal PDZ-binding motif of other proteins. PDZ domains are protein-protein interaction modules that play a role in protein complex assembly. The PDZ domain, which is widespread in bacteria, plants, yeast, metazoans, and Drosophila, allows the assembly of large multi-protein complexes. The multi-protein complexes act in intracellular signal transduction, protein targeting, and membrane polarization. The identified PDZ domain-containing proteins located at autotypic junctions include zonula occludens-1 (ZO-1), ZO-2, pals-1-associated tight junction protein (PATJ), multi-PDZ domain proteins (MUPPs), membrane-associated guanylate kinase inverted 2 (MAGI2), and protease-activated receptor (PAR)-3. PAR-3 interacts with atypical protein kinase C and PAR-6, forming a ternary complex, which plays an important role in the regulation of cell polarity. MAGI2 interacts with ${\alpha}$-amino-3-hydroxyl-5-methyl-4-isoxazole propionate (AMPA) receptor at excitatory synapses. PATJ is detected in paranodal loops associated with claudin-1. On the other hand, MUPP1 is found in mesaxons and Schmidt-Lanterman incisures with claudin-5. ZO-1, ZO-2, and PAR-3 are found at all three sites. Different distributions of PDZ domain-containing proteins affect the development of autotypic junctions. In this review, we will describe PDZ domain-containing proteins at autotypic tight junctions in myelinating Schwann cells and their roles.

• Korean Journal of Remote Sensing
• /
• v.34 no.2_2
• /
• pp.377-391
• /
• 2018

In order to efficiently monitor red tide over a wide range, the need for red tide detection using remote sensing is increasing. However, the previous studies focus on the development of red tide detection algorithm for ocean colour sensor. In this study, we propose the use of multi-sensor to improve the inaccuracy for red tide detection and remote sensing data in coastal areas with high turbidity, which are pointed out as limitations of satellite-based red tide monitoring. The study area were selected based on the red tide information provided by National Institute of Fisheries Science, and spatial fusion and spectral-based fusion were attempted using GOCI image as ocean colour sensor and Landsat OLI image as terrestrial sensor. Through spatial fusion of the two images, both the red tide of the coastal area and the outer sea areas, where the quality of Landsat OLI image was low, which were impossible to observe in GOCI images, showed improved detection results. As a result of spectral-based fusion performed by feature-level and rawdata-level, there was no significant difference in red tide distribution patterns derived from the two methods. However, in the feature-level method, the red tide area tends to overestimated as spatial resolution of the image low. As a result of pixel segmentation by linear spectral unmixing method, the difference in the red tide area was found to increase as the number of pixels with low red tide ratio increased. For rawdata-level, Gram-Schmidt sharpening method estimated a somewhat larger area than PC spectral sharpening method, but no significant difference was observed. In this study, it is shown that coastal red tide with high turbidity as well as outer sea areas can be detected through spatial fusion of ocean colour and terrestrial sensor. Also, by presenting various spectral-based fusion methods, more accurate red tide area estimation method is suggested. It is expected that this result will provide more precise detection of red tide around the Korean peninsula and accurate red tide area information needed to determine countermeasure to effectively control red tide.

• Korean Journal of Plant Taxonomy
• /
• v.32 no.3
• /
• pp.257-292
• /
• 2002

Morphological characters of sections Foetidae(one taxon), Arenariae(one taxon) and Multiflorae(six taxa) of genus Carex(Cyperaceae) were reexamined. The epidermal patterns of perigynium, achene and leaf were investigated using by a scanning electron microscope(SEM) and a light microscope(LM). Morphological characters, such as length and width of stem, leaf, leaf sheath, bract, spike, scale, perigynium and beak of perigynium, length of spike peduncle, size and frequency of stomatal complex of leaf, number of bract, shape of stem transection, scale and apex of scale, beak and base of perigynuim, achene, epidermal cell and cell wall of perigynium, achene, leaf epidermal patterns(fundamental epidermal cell and cell wall, silica body, subsidiary cell), hair, papillae present/absent of perigynium, and leaf were useful for the identification of observed eight taxa. According to the current study, examined eight taxa of sections Foetidae, Arenariae and Multiflorae were distinct from each other with respect to length and width of stem, leaf, bract, perigynium, perigynium beak, length of spike peduncle, shape of bract, scale and apex of scale, perigynium, perigynium beak, hair presence/absence of perigynium and leaf. A key based on data was presented here.

• Korean Journal of Social Welfare
• /
• v.67 no.2
• /
• pp.61-84
• /
• 2015

The purpose of this study was to develop the Post-bereavement Growth Inventory(PBGI) for the elderly and to evaluate its validity. The items for developing PBGI were compiled from a literature search, content validity review, and a preliminary survey. A main survey of 308 widowed persons(aged 60+) was conducted. The results were as follows. First, an exploratory factor analysis revealed six factors of the PBGI. The results of the confirmatory factor analysis supported a five-factor structure for the final 24 scale items of scale. Second, in terms of concurrent validity, the PGBI compared favorably with the "Personal Growth" scale from The Hogan Grief Reaction Checklist (HGRC: Hogan and Schimdt, 2001). Third, the results of contrast group validity tests demonstrated that the group scoring in the upper 30% on the scales of Psychological Well-being (PWB, Ryff and Keyes, 1995) and the Grief Reaction Inventory (GRI: Remondet and Hansson, 1987) showed a significantly higher degree of post-bereavement growth (PBG) than the group scoring in the lower 30%. Fourth, Cronbach's ${\alpha}$ values for the five factors were between .649-.856 and .907 overall, indicating high internal consistency. Finally, education had the most significant influence on PBG. All results indicated the high validity of the PBGI. The findings from this study could provide the rationale for practical interventions from a growth-oriented perspective for widowed persons, as well as an objective assessment tool for practitioners in clinical areas.

• The Korean Journal of Nuclear Medicine
• /
• v.29 no.1
• /
• pp.48-53
• /
• 1995

This study investigates a simple mathematical model for the quantitative estimation of regional myocardial blood flow in experimental canine coronary artery thrombosis using Rb-82 dynamic myocardial positron emission tomography. The coronary thrombosis was induced using the new catheter technique by narrowing the lumen of coronary vessel gradually, which finally led to partial obstruction of coronary artery. Ten Rb-82 dynamic myocardial PET scans were performed sequentially for each experiment using our 5, 10 and 20 second acquisition protocol, respectively, and three regions of interest were drawn on the transaxial slices, one on left ventricular chamber for input function and the other two on normal and decreased perfusion segments for the flow estimation in those regions. Single compartment model has been applied to the measured sets of regional PET data, and the rate constants of influx to myocardial tissue were calculated for regional myocardial flow estimates with the three parameter fits of raw data by the Levenberg-Marquardt method. The results showed that, (1) single compartment model suggested by Kety-Schmidt could be used for the simple estimation of regional myocardial blood flow, (2) the calculated regional myocardial blood flow estimates were dependent on the selection of input function, which reflected partial volume effect and left ventricular wall motion, and (3) mathematically fitted input and tissue time activity curves were more suitable than the direct application of the measured data in terms of convergence.