• Proceedings of the National Institute of Ecology of the Republic of Korea
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• v.1 no.1
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• pp.74-82
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• 2020

Predictions of suitable habitat areas can provide important information pertaining to the risk assessment and management of alien plants at early stage of their establishment. Here, we predict the invasion potential of Muhlenbergia capillaris (pink muhly) in South Korea using five bioclimatic variables. We adopt four models (generalized linear model, generalized additive model, random forest (RF), and artificial neural network) for projection based on 630 presence and 600 pseudo-absence data points. The RF model yielded the highest performance. The presence probability of M. capillaris was highest within an annual temperature range of 12 to 24℃ and with precipitation from 800 to 1,300 mm. The occurrence of M. capillaris was positively associated with the precipitation of the driest quarter. The projection map showed that suitable areas for M. capillaris are mainly concentrated in the southern coastal regions of South Korea, where temperatures and precipitation are higher than in other regions, especially in the winter season. We can conclude that M. capillaris is not considered to be invasive based on a habitat suitability map. However, there is a possibility that rising temperatures and increasing precipitation levels in winter can accelerate the expansion of this plant on the Korean Peninsula.

• 보존과학연구
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• s.27
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• pp.103-128
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• 2006

Rock properties of the five storied stone pagoda in the Mooryangsa temple are consist mainly in medium grained biotite granite with partly pegmatite veinlet. A part of the foundation stone is substituted in identical rock properties of the pagoda. The upper part of the pagoda is used purples and stone, gray shale and granodiorite. The most serious problem of the pagoda is structual instability from centered subsidence of the ground in northwestern direction remarkably. In southern view, the upper part of the pagoda also is slanted a little in right, it will need reinforcement by engineering method for structual stability of the stone pagoda. Weathering states of the stone pagoda are affected results of natural and artifical factors due to the surface-exfoliation, fine-fissure, crack, falling offs. On the rock surface of the pagoda, ferro-manganese hydroxide compounds are coated along the rainpathway. Also, bryophyte range concentration spreads raindrops face of roof rock properties, which areadd biological weathering effects. For the synthetic evaluation of the deterioration state, we make detailed surface weathering maps, it will be contribute to investigation for future conservation schemes.

• Smart Structures and Systems
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• v.17 no.1
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• pp.17-29
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• 2016

Ultrasonic tomography is a powerful tool for identifying defects within an object or structure. But practical application of ultrasonic tomography to solids is often limited by time consuming transducer coupling. Air-coupled ultrasonic measurements may eliminate the coupling problem and allow for more rapid data collection and tomographic image construction. This research aims to integrate recent developments in air-coupled ultrasonic measurements with current tomography reconstruction routines to improve testing capability. The goal is to identify low velocity inclusions (air-filled voids and notches) within solids using constructed velocity images. Finite element analysis is used to simulate the experiment in order to determine efficient data collection schemes. Comparable air-coupled ultrasonic signals are then collected through homogeneous and isotropic solid (PVC polymer) samples. Volumetric (void) and planar (notch) inclusions within the samples are identified in the constructed velocity tomograms for a variety of transducer configurations. Although there is some distortion of the inclusions, the experimentally obtained tomograms accurately indicate their size and location. Reconstruction error values, defined as misidentification of the inclusion size and position, were in the range of 1.5-1.7%. Part 2 of this paper set will describe the application of this imaging technique to concrete that contains inclusions.

• The Journal of the Korea institute of electronic communication sciences
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• v.8 no.10
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• pp.1573-1580
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• 2013

This study is proposed traffic signal operating system to find existing problems of loop system and complex with doplar system, which have strong linearity, resistence of weather effects and wide range to improve delay problems that used in vehicle detection method. This proposed method have simulated on Southern-Gwangju station to Enter of SeoChang take about 10km by using VISSIM tool and we found this proposed method is 15% through(또는 to) 30% more effective than continuous progress interlocking system or crossing progress interlocking system.

• The Journal of Engineering Geology
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• v.1 no.1
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• pp.2-10
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• 1991

Some geotechnical considerations might be suggested to the construction performance from the school and the housing projects in Tripoli sub-region, Libya. The subsurface informations were compiled from the site investigation reports, for which more than 700 borings and lots of laboratory test had been conducted from 1984 to 1986. Most subsurface of 10 meter depth in the Jafara plain consists of medium dense silty sand. Some ground in the plain have poor top soil with interbedded calcarenite or limestone. The shallow subsurface is found to be very poor soil in the southern mountain range. Weak soil is hardly found except in the sabkha area. In general, natural silty sand layer may have a presumed bearing capacity of more than 150kN/$m^2$, where spread or strip footing is applied. Proper fine aggregate and natural coarse one are restricted in Tripoli sub-region. Coarse aggregate is generally supplied from the dolomite quarry.

• Environmental Engineering Research
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• v.10 no.6
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• pp.306-315
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• 2005

Total gas phase mercury (TGM) concentrations and event wet-only precipitation for Hg were collected for nine months (from April, 2002 to Dec., 2002) at Sterling, NY on the shoreline of Lake Ontario. TGM concentrations measured in this study ($3.02{\pm}2.14\;ng/m^3$) were in somewhat high range compared to other background sites. Using simplified quantitative transport bias analysis (SQTBA) possible sources affecting high Hg concentration in Sterling was identified, and they are coal-fired power plants located in southern NY and Pennsylvania. Wet deposition measured at Mercury Deposition Network (MDN) sites including Pt. Petre and Egbert, ON were compared with data obtained at the Sterling to estimate the total mercury wet deposition flux to Lake Ontario. The wet deposition flux was calculated to be the highest at the Sterling site ($7.94\;{\mu}g/m^2$ from April, 2002 to Dec. 2002) and the lowest at the Egbert ($3.92\;{\mu}g/m^2$), due to the both the difference in precipitation depth and Hg concentration in the precipitation. The deposition measured at the Sterling site is similar to Lake Michigan deposition of $6-14\;{\mu}g/m^2$ (converted for ninth months) measured for Lake Michigan Mass Balance Study (LMMBS).

• Economic and Environmental Geology
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• v.4 no.2
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• pp.59-75
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• 1971

Orogenic cycle is closely related with sedimentary cycle, and a sedimentary cycle involves the birth, development and disappearance of a sedimentary basin. Paleontological studies have indicated that birth or disappearance of sedimentary basins of separated regions frequently coincided in time. In this paper, the writer presents his assumption on the East Asian analogy of the Hercynian orogenic cycle in accord to the above mentioned generalities. Previous studies, including mine have a corollary that Korea and Southern China, which had been uplifted by the Caledonian movement, changed into low-lying region with subsiding areas in the Givetian time. The writer, thus, thinks that the Hercynian orogenic cycle started in Givetian, and that the Mongolian geosyncline in China, the Gangweon Basin in Korea and the Honshu geosyncline in Japan disappeared in the Ladinian. The writer, therefore, thinks that the Ladinian marks the end of the Hercynian orogenic cycle, but this assumption will have to be rechecked in consideration with the Alpine orogenic cycle. The Late Namurian-Early Bashkirian time, the dividing period between the early and late Hercynian orogenic cycle, is thought to correspond the time of the Hongjeom Series deposition. The writer is also of the view that the Akiyoshi orogenic cycle(T. Kobayashi) corresponds the late Hercynian phase, and that the Abenian movements(M. Minato) corresponds to the range from the late Caledonian phase to the former part of late Hercynian phase.

• Journal of the Korean Institute of Navigation
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• v.3 no.1
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• pp.29-46
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• 1979

The climate of a given region is determined by the combination of the various climatic elements. But among them, the temperature is the most important element to classify the climatic type. The author attempted to classify the climatic types in Korea by making a analysis of the characteristics of temperature distribution. To accomplish the study, the author analyzed the daily and yearly range of temperature, the warmest and coldest months, continentality and oceanicity, thermal anomaly, and relative temperature, etc. The data of 153 weather stations are used for the analysis of the above five criteria. As a result of the study, the climate of Korea can be divided into three types, namely, the continental, coastal and intermediate(or transitional) type. The Pronounced continental type is appeared in the northern part of highland area. And the coastal type is limited to the east and south coast areas, and the southern part of the west coast area. The continentality is larger, and the oceanicity smaller, than those of Siberia, Mongolia and the inland area of China where the continental climate is most remarkable in the world. The reason why the west coast area is more continental than the east coast area may be due to the terrain effect and the warm current going north along the east coastline.

• Journal of environmental and Sanitary engineering
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• v.23 no.2
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• pp.1-18
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• 2008

The tetrachloroethylene (PCE) dehalogenase of Clostridium bifermentans DPH-1 (a halorespiring organism) was purified, cloned, and sequenced. This enzyme is a homodimer with a molecular mass of ca. 70 kDa and exhibits dehalogenation of dichloroethylene isomers along with PCE and trichloroethylene (TCE). Broad range of substrate specificity for chlorinated aliphatic compounds (PCE, TCE, cis-1,2-dichloroethylene, trans-1,2-dichloroethylene, 1,1-dichloroethylene, 1,2-dichloropropene, and 1,1,2-trichloroethane) for this enzyme was also observed. A mixture of propyl iodide and titanium citrate caused a light-reversible inhibition of enzymatic activity suggesting the involvement of a corrinoid cofactor. A partial sequence (81 bp) of the encoding gene for PCE dehalogenase was amplified and sequenced with degenerateprimers designed from the N-terminal sequence (27 amino acid residues). Southern analysis of C. bifermentans genomic DNA using the polymerase chain reaction product as a probe revealed restriction fragment bands. A 5.0 kb ClaI fragment, harboring the relevant gene (designated pceC) was cloned (pDEHAL5) and the complete nucleotide sequence of pceC was determined. The gene showed homology mainly with microbial membrane proteins and no homology with any known dehalogenase, suggesting a distinct PCE dehalogenase. So, C. bifermentans could play some important role in the initial breakdown of PCE and other chlorinated aliphatic compounds in sites contaminated with mixtures of halogenated substances.

• The Plant Pathology Journal
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• v.15 no.2
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• pp.119-123
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• 1999

Chrysanthemums showing leaf mottling were collected from three southern locations in Korea in 1998. Two kinds of viruses were isolated from the leaves and were identified as tomato aspermy virus ch-TAV) and chrysanthemum virus B (ch-CVB), according to their host range, morphology, intracellular location, agar gel double diffusion test, and double-stranded RNA (dsRNA) analysis. The purified ch-TAV was spherical particles of approximately 29 nm in diameter and ch-CVB was filamentous particles of 685 nm long. Inclusion bodies were not observed in ch-TAV and/or ch-CVB infected chrysanthemum. ch-TAV showed positive serological reaction with TAV antiserum (ATCC-127) but not with CMV-pepper antiserum. In dsRNA analysis, four kinds of viral dsRNA were observed on ch-TAV and one viral dsRNA was shown on ch-CVB. Rate of co-infection with TAV and CVB in commercial chrysanthemums was 20.9%. On the other hand, infection with CVB alone was 97.2%. However, chrysanthemums naturally infected with TAV alone were not found.