• Journal of Bio-Environment Control
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• v.12 no.3
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• pp.114-120
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• 2003

In order to provide fundamental data for development of controlled environment facilities in Korean ginseng (Panax ginseng C.A. Meyer) cultivation, field survey and analysis of structural and environmental engineering characteristics on the shading structures in ginseng fields (the ginseng houses) were carried out. In this study shading structures for ginseng cultivation were classified according to their structural materials, connection types, and detailed structures. That is they were classified into wood or steel frames, single or multi spans, and frame or cable types. As a result of the investigation, standardization of structural materials, fabrication and construction methods arc required. And it was considered that a reinforced design and a countermeasure for heavy snow are the most important matters for structural improvement. In parts of the environmental management, researches for setting up the irrigation standard are required in the first place. And it was investigated that an installation of the shading structures is a work being the most hard, taking a lot of time, and having need for automation. So controlled environment ginseng houses, with a low cost, a structural safety and a satisfactory workability, should be developed.

• Journal of the Korean Geotechnical Society
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• v.32 no.10
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• pp.17-29
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• 2016

A debris flow analysis model has been developed to simulate the erosion and entrainment of soil layer. Special attention is given to the model which represents strength softening behaviour of soil layer due to velocity of deformation. The 3D FE analysis by Coupled Eulerian-Lagrangian (CEL) model is conducted to simulate the debris flow. The model is validated using published data on laboratory experiment (Mangeny et al., 2010). It has been definitely shown that proposed model is in good agreement with the results of laboratory data. Futhermore, the FE analysis is conducted to ensure capability of simulating the real scale debris flow. The result of Ramian watershed, Korea shows that the debris flow has increased the volume and speed and it is in good agreement with field investigation. Based on this, it is confirmed that proposed model shows good agreement of the behavior of the actual and analytical debris flow.

• Journal of the Korean Magnetics Society
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• v.19 no.6
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• pp.209-215
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• 2009

M-type barium ferrite (BaFe12O19) powders were synthesized through the co-precipitation method. Starting material composition $Fe^{3+}:\;Ba^{2+}$ mole ratio was fixed as 8 and the relative amount of $Fe^{3+}$ and $Ba^{2+}$ was controlled. Structure and magnetic properties and powder morphology were investigated using XRD, SEM, VSM. Powder showing high coercivity and small magnetization was obtained at pH8 and $Fe_{3+}:\;Ba_{2+}$ of 12 : 1.5. Small magnetization value was originated from the existence of ${\alpha}-Fe_2O_3$. Single-phase Mtype barium ferrite were obtained regardless of the heat treatment condition and the amount of $Fe_{3+}\;and\;Ba_{2+}$ at pH$\approx$10. The largest value of magnetization (55.7 emu/g) under investigation were obtained when $Fe_{3+}:\;Ba_{2+}$ of 13.6 : 1.7 and furnace cooled powder in $O_2$. Particle size of powder was in the range of 50~200 nm.

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.2
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• pp.253-259
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• 2018

In February 2014, the rudder upper stock and the nut of a passenger ship were released and an accident occurred. That accident occurred because the steering gear of passenger ships that was intended to move many passengers. The accidents due to steering gear was zero according to 2010-2016 statistics. There is no rules prevent loosening of the upper rudder nut in "Ship Safety Act" and "Structural standard of steel ship". Since the accident, the Korea register has been revised to the joining method in Part 5 Chapter 7 of the rules in the classification of steel ships. In the field survey of 12 passenger ships operating on Mokpo and surrounding islands, the welding method was applied in the cases as the fastening method. The fastening type was equipped with two C-type structures. It was structured to be difficult to access. The NAS 3350 test was conducted to investigate ways to prevent homologous accident considering the characteristic of passenger ships that need to lift or unload rides once a year.

• Journal of Plant Biology
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• v.2 no.1
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• pp.14-21
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• 1959

The bamboo, one of staples of South-East Asia, has 1, 250 species in 46 Genus throughout the world South-East Asia, it's main habitat, has 1, 180 species, while South America has about 70 species or so. Major places of it's production in Asia are Korea, southern China, Japan, Malay, Ceylon, Formosa, and Philipine, but of these, Korea, southern China, and Japan are the most famous places for their production of excellant bamboo. In Korea, Kyongsang-Namdo and Cholla-Namdo are known as it's home, occupying 80 per cent of the total area of bamboo production in this country. Kyongsang-Pukdo, Cholla-Pukdo, Chungehong-Namdo, and Kangwon-do are also known as it's minor production. The importance of the bamboo can not be ignored, considering it's role in the industrial development of this country; the bamboo-ware is indispensable for the culture of laver which annually secures a considerable amount of foreign money. But it has long been regreted that the home-made bamboo-ware is far from being able to meet the ever increasing demand in quantity and is forced to be imported annually. In the light of the above mentioned fact, much interested; I undertook the task of investigating the bamboo in this country, Primarily concerned in it's kind and distribution, and could draw the following conclusions as the first phase of my investigation: (1). The amount of the bamboo accumulation in this country, compared with that of pre-worldwar II, is reduced as much as 300, 000 fagots(on fagot amounts to 25 pieces), and now the acreage of the bamboo field is 32, 200$\textrm{km}^2$s. (2). At a mountian peak in Kunoe-myon Wando-kun Cholla-Namdo, I found out a new specis. (Shasamorpha chiisanensis NAKAI Forma wan-Ponia H. P. CHONG) (3). The kinds of the autogenous wild bamboo in this country are as follows; a). 8 kinds in Sinoarundinaria. (5 Spp; 2 For; 1 Var) b). 1 kinds in Pieioplastus. (1 Spp) c). 2 kinds in Pseudosasa. (1 Spp; 1Var.) d) 4 kinds in Sasamorpha. (2 Spp; 1 For.; 1 Var.) e). 4 kinds in Sasa. (4 Spp) In total there are nineteen(19) kinds of autogenous wild bamboo in this country. When adding to this thethirty five (35) species which the japanese has transplanted in Kyongsang-Namdo Forestry Expreimental stations, there are in all fifty four (54) spe ies in this country. (4). As for the distribution of the Northern limitation of the bamboo growing, I found that Sinoarundinaria nigra OHWI var, Henonis HONDA can be cultivated as for as Kosongkun, Kangwon-Do, andSinoarundinaria pubescens HONDA as for as Clung Chong Namdo, and Sinoarundinaria reticulata as far as chung Chong-Pukdo.

• Korean Journal of Environment and Ecology
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• v.22 no.1
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• pp.35-42
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• 2008

This study was conducted to provide basic information that can be used to restore habitats of Nannophya pygmaea. Nannophya pygmaea is an endangered species of wildlife fauna in Korea and its habitats are distributed very scarcely in Korea. Ten wetland sites throughout Korea, where N. pygmaea inhabited (2 sites in Incheon Muui-do, 1 site in Gokseong Singi-ri, 4 sites in Gokseong Wolbong-ri, and 3 sites in Mungyeong Yulsu-ri) were investigated from June 2006 to August 2007. Investigation was made on landscape properties, habitat sizes, vegetation types, water environments, and water sources. N. pygmaea was generally found in the abandoned paddy fields surrounded by mountains. The habitats ranged from $113.4m^2$ to $1,153.1m^2$ in area, and were mostly dominated by Juncus effusus and Persicaria thunbergii. The water level was $2.6\sim7.3cm$, and the water temperature ranged from $16^{\circ}C$ to $27.8^{\circ}C$. The elevation of the habitats ranged from 139 to 243 m above sea level, which was mostly lower than that of other high mountain wetland habitats. In conclusion, the habitats of N. pygmaea can be restored at wetlands, which have similar condition with field habitat such as abandoned paddy fields in the beginning stage of oligotrophy. Because N. pygmaea is sensitive to microtopography and other surrounding environments, the approach to restore the habitats for N. pygmaea should consider those microhabitat conditions shown in this study.

• The Journal of the Acoustical Society of Korea
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• v.24 no.8
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• pp.469-480
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• 2005

There have been always some difficulties in target setting and conditioning of acoustic performances or the Korean traditional music hall due mainly to the lack of the information on the sound radiation characteristics of Korean musical sources. As the 2nd experiment succeeding the previous study[1], the radiation characteristics of eight typical Korean traditional musical sources were investigated if precision. The selected musical sources were Geomungo, Haegeum (string), Piri, Taepyeongso (woodwind), Buk, Kwaengguari, Jing (drum), and male Pansori Chang (vocal Performance). The results show that the directivity pattern of each instrument is different and has their own directivity characteristics. Measured directional and spectral characteristics of traditional Korean music sources were implemented into the computation of architectural acoustic measures. Significant differences in the acoustic measures at receiver positions were observed between the results in using the omni-directional source and the directional one. In order to investigate the acoustical characteristics of the instruments depending on the spatial variation four different shapes of halls were introduced including rectangular, fan. horse-shoe and geometrical shapes. Room acoustical parameters such as RT, SPL, C80, LF, STI were calculated at each type or hall. As the results, It was found that the rectangular hall has the most high clarity. lateral energy and STI values among low shapes of halls. It is thought that the suggested source data and design method can be used as a basic reference in the future acoustic design of performance halls for the Korean traditional music.

• Journal of the Korean Chemical Society
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• v.47 no.6
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• pp.645-658
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• 2003

This study was carried out to analyze inquiry area of the chemistry (II) textbooks which were published by the 7th curriculum. The study attempts to analyze the degree to which chemistry (II) textbooks reflected the guidelines of the 7th science curriculum and propose educational suggestions for the inquiry learning. The analysis of the inquiry area was carried out based on the suggested inquiry elements of the 7th science curriculum. Overall, for the analysis of inquiry elements, basic inquiry elements except classifying suggested by the 7th science curriculum were well reflected on the textbooks. However, for the integrated inquiry elements, interpreting data takes almost half of the total integrated inquiry elements. Other integrated inquiry elements except drawing conclusion and transforming data were reflected less than ten percent. Investigation was also reflected less than ten percent of all inquiry activity. And inquiry activities were limited in terms of variety with few projects and no field trip. The main essence of the 7th science curriculum is the emphasis on total inquiry learning through various integrated inquiry elements and inquiry activities for higher grade students. Thus it is suggested that teachers provide inquiry learning which can supplement the textbook.

• Journal of the Korean Chemical Society
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• v.47 no.6
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• pp.633-644
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• 2003

The purpose of this study was to analyze the inquiry elements and inquiry activity of the inquiry area in chemistry I textbooks authorized by 7th curriculum. It was to confirm suitable reflection of the 7th science curriculum and to find educational suggestions of inquiry learning. It was found that the basic inquiry elements except measuring and classifying were well reflected on the textbooks. However, only several integrated inquiry elements and the inquiry activities were well reflected on the same textbooks. For the integrated inquiry elements, interpreting data was shown as the tower above the rest inquiry elements. In the analysis of inquiry activity, the numbers of experiment is placed almost half of all inquiry activities. The sum of two numbers of investigation and discussion is similar ratio to experiment but field trip and project are rarely or low ratio. As the integrated inquiry elements and inquiry activities were not balanced for various inquiry learning. It is suggested that learners be educated with complementary of these aspects in inquiry learning.

• Korean Journal of Plant Resources
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• v.29 no.1
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• pp.90-109
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• 2016

This study aims to investigate the flora of Mt. Cheonma (Namyangju-si, Gyeonggi-do, Korea), including Korean endemic, rare and endangered plants. To support the biodiversity and usefulness of this investigation, we checked the red list plants, floristic regional indicator plants, climate change adaptation target plants and naturalized plants, and compared composition of plant species in Mt. Cheonma with nearby mountains. Totally, we performed 22 field investigations from April 2012 to October 2014. The number of vascular plants in this region is 433 taxa and comprised of 94 families, 266 genera, 378 species, 2 subspecies, 46 varieties, and 7 forms. Among them, there are 13 endemic plants designated by Korean Forest Service, whereas only 10 taxa are endemic species by Korean Ministry of Environment (KME). According to the IUCN criteria, there are 12 rare and endangered plants composed of 9 Least Concerned (LC), 2 Vulnerable species (VU), and one Endangered species (EN) found by Korea National Arboretum (KNA). Meanwhile, 8 taxa including 7 Least Concerned (LC) were found in Red List of KME. The floristic regional indicator plants designated by KME were 49 taxa. In addition, there are 14 taxa in The Adaptable to Climate Change Plant List designated by KNA, while only 19 taxa are naturalized plants. Generally, there are 190 common taxa in Gwangju Mountains area, and only 51 taxa are distributed in Mt. Cheonma.