• Title/Summary/Keyword: North America

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Nail Shear Performance of Structural Members with OSB (오에스비에 대한 각종 부재의 못전단성능)

  • Hwang, Kweonhwan;Park, Moon-Jae
    • Journal of the Korean Wood Science and Technology
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    • v.36 no.4
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    • pp.66-76
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    • 2008
  • Recently, demands for the structural uses with domestic Japanese larch and SPF(spruce-pine-fir) lumber from North America have been increased. Shear properties of nailed joints that are the most simple and optimum fastening method in wooden constructions, especially in light frame construction. For the nailed joints, in North America and Japan, a number of basic and practical studies have been performed. The shear behaviors for the double nailed joint with variations of member and its direction, were examined. Shear properties of the shear specimens with SPF stud showed more remarkable variation than larch glulam and larch stud. Furthermore, the relationships between slip modulus and strength are not coincided in every case.

A Comparative Study of Graduate Archival Programs in Korea and North America (기록학 대학원 교육 프로그램에 관한 비교 연구 - 한국과 북미를 중심으로 -)

  • Chung, Yeon-Kyoung
    • Journal of the Korean Society for Library and Information Science
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    • v.37 no.1
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    • pp.81-100
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    • 2003
  • The purpose of this study is to find necessary factors and to suggest the future directions for the successful graduate archival education in Korea by comparing current programs hi Korea and North America. Name of the schools, credits, required and elective courses, practice, research and thesis are compared by analyzing web sites and literature review. Development of more various Master's programs, a separate degree in Master of Archival Studies, more credits for the degree, standardization of curriculum, and the working environments for practicum, internship and research are found as important elements for the program. In the end, more collaborations with other disciplines, more faculties with working experiences and Ph. D. degree in archival studies, communications among the universities, archival institutions and professional societies/associations, continuous research on the programs, improvement of the quality of archivists, strong national supports for archives and records and establishment of the strong quality control for being archivists are suggested for the future directions.

A study on the occurrance real status of naturalized plants in urban green space (공원녹지내 사화직물 출현실태 분석에 관한 연구)

  • 노재현
    • Journal of the Korean Institute of Landscape Architecture
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    • v.26 no.3
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    • pp.66-77
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    • 1998
  • The purpose of this study is on identifying real condition of naturalized plants in urban green space. For this, Chollabak-do region was selected for case study. The occurring frequency and distribution status was investigated by field survey. The area of green open space, level of management and passed years after construction etc, were analized to identify the influence on occurrence of naturalized plants. The result is as follows: 1. In 18 sites, 145 taxa as weed species including naturalized plants were occurred. Average No. of occurring taxa is 22.7. Two families of plants, Graminae and compositae charged the most part. Also the rate of naturalized plant among them is 29.7%. 2. Naturalized species showing high occurring rate are 14 taxa of compositae, 5 taxa of Gramineae, Leguminosae and 4 taxa of cruciferae. These plants of previous four somatic polymorphism among all the naturalized plants. 3. The taxa number of naturalized plants were reducedby intensive management. But the rate of naturalized plants in extensively managed area was relatively lower than intensively managed one. Naturalizd plants were widely distributed in most of urban green space with being cognitioned as whole weed. 4. In origin of naturalized plants, the taxa from north America were 16 and the taxa from Europe were 16. Therefore the rate originated from north America and Europe charged high part as 68.2%. The rate of Annual, Biennial and Perennial were each 78.7%, 21.3%. The alternative of management for control aganist disturbance by Annual & Biennial required. 5. Multi-relations analysis shows 0.81 which is the relatively high interralation between the number of emerged axa and that of naturalized ones. 6. The number of naturalized species has no relation to the lapse of years after construction of open-space. Especially it was identified that weed control in the beginning of construction is very important. On the other hand the relation between Ys and Xp was Ys=1.784Xp+4.646.

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X11ARIMA Procedure (한국형 X11ARIMA 프로시져에 관한 연구)

  • 박유성;최현희
    • The Korean Journal of Applied Statistics
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    • v.11 no.2
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    • pp.335-350
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    • 1998
  • X11ARIMA is established on the basis of X11 which is one of smoothing approach in time series area and this procedure was introduced by Bureau of Census of United States and developed by Dagum(1975). This procedure had been updated and adjusted by Dagum(1988) with 174 economic index of North America and has been used until nowadays. Recently, X12ARIMA procedure has been studied by William Bell et.al. (1995) and Chen. & Findly(1995) whose approaches adapt adjusting outliers, Trend-change effects, seasonal effect, arid Calender effect. However, both of these procedures were implemented for correct adjusting the economic index of North America. This article starts with providing some appropriate and effective ARIMA model for 102 indexes produced by national statistical office in Korea; which consists of production(21), shipping(27), stock(27), and operating rate index(21). And a reasonable smoothing method will be proposed to reflect the specificity of Korean economy using several moving average model. In addition, Sulnal(lunar happy new year) and Chusuk effects will be extracted from the indexes above and both of effects reflect contribution of lunar calender effect. Finally, we will discuss an alternative way to estimate holiday effect which is similar to X12ARIMA procedure in concept of using both of ARIMA model and Regression model for the best fitness.

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Evaluation of different molecular methods for detection of Senecavirus A and the result of the antigen surveillance in Korea during 2018

  • Heo, JinHwa;Lee, Min-Jung;Kim, HyunJoo;Lee, SuKyung;Choi, Jida;Kang, Hae-Eun;Nam, Hyang-Mi;Nah, JinJu
    • Korean Journal of Veterinary Service
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    • v.44 no.1
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    • pp.15-19
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    • 2021
  • Senecavirus A (SVA), previously known as Seneca Valley virus, can cause vesicular disease and neonatal losses in pigs that is clinically indistinguishable from foot-and-mouth disease virus (FMDV). After the first case report in Canada in 2007, it had been restrictively identified in North America including United States. But, since 2015, SVA emerged outside North America in Brazil, and also in several the Asian countries including China, Thailand, and Vietnam. Considering the SVA occurrence in neighboring countries, there has been a high risk that Korea can be introduced at any time. In particular, it is very important in terms of differential diagnosis in the suspected case of vesicular diseases in countries where FMD is occurring. So far, several different molecular detection methods for SVV have been published but not validated as the reference method, yet. In this study, seven different molecular methods for detecting SVA were evaluated. Among them, the method by Flowler et al, (2017) targeted to 3D gene region with the highest sensitivity and no cross reaction with other vesicular disease agents including FMDV, VSV and SVD, was selected and applied further to antigen surveillance of SVA. A total of 245 samples of 157 pigs from 61 farms submitted for animal disease diagnose nationwide during 2018 were tested all negative. In 2018, no sign of SVA occurrence have been confirmed in Korea, but the results of the surveillance for SVA needs to be continued and accumulated at a high risk of SVA in neighboring countries.

The description of Haematococcus privus sp. nov. (Chlorophyceae, Chlamydomonadales) from North America

  • Mark A. Buchheim;Ashley Silver;Haley Johnson;Richard Portman;Matthew B. Toomey
    • ALGAE
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    • v.38 no.1
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    • pp.1-22
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    • 2023
  • An enormous body of research is focused on finding ways to commercialize carotenoids produced by the unicellular green alga, Haematococcus, often without the benefit of a sound phylogenetic assessment. Evidence of cryptic diversity in the genus means that comparing results of pigment studies may be confounded by the absence of a phylogenetic framework. Moreover, previous work has identified unnamed strains that are likely candidates for species status. We reconstructed the phylogeny of an expanded sampling of Haematococcus isolates utilizing data from nuclear ribosomal markers (18S rRNA gene, 26S rRNA gene, internal transcribed spacer [ITS]-1, 5.8S rRNA gene, and ITS-2) and the rbcL gene. In addition, we gathered morphological, ultrastructural and pigment data from key isolates of Haematococcus. Our expanded data and taxon sampling support the concept of a new species, H. privus, found exclusively in North America. Despite overlap in numerous morphological traits, results indicate that ratios of protoplast length to width and akinete diameter may be useful for discriminating Haematococcus lineages. High growth rate and robust astaxanthin yield indicate that H. rubicundus (SAG 34-1c) is worthy of additional scrutiny as a pigment source. With the description of H. privus, the evidence supports the existence of at least five, species-level lineages in the genus. Our phylogenetic assessment provides the tools to frame future pigment investigations of Haematococcus in an updated evolutionary context. In addition, our investigation highlighted open questions regarding polyploidy and sexuality in Haematococcus which demonstrate that much remains to be discovered about this green flagellate.

Case Study of the Roles and Characteristics of Community Gardens in Four North American Cities (북미 4개 도시 커뮤니티가든 사례조사에 의한 역할과 특성 비교 연구)

  • Shin, Myungjin;Choi, Jungmin
    • Journal of the Korean Institute of Landscape Architecture
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    • v.46 no.6
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    • pp.26-40
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    • 2018
  • As urban regeneration and revitalization projects become increasingly popular in Korea, interests in residential environment, landscape improvement and community activities have risen, resulting in increased interest in community garden, a type of urban agriculture. However, the concept of community garden in Korea is yet to be defined apart from the general concept of urban agriculture. Also, any discussion regarding a practical scheme for community gardens remains nascent. Therefore, in order to define and to understand community gardens, and to draw meaningful implications for the community garden research in Korea, this study conducted a preliminary field survey of four North American cities from where the idea of community gardening originates. A total of 166 community gardens in Seattle, New York, Philadelphia and Vancouver were visited during this survey. Four community gardens from each city were selected for further analysis, with particular emphasis on spatial organization and social functions. The results showed that the community gardens in each city perform a diverse array of functions depending on location, type and societal needs. Community gardens in Seattle and Vancouver, which may be classified as 'uptown,' focused on their roles as fields of 'community participation.' Those in New York and Philadelphia, which are classified as 'downtown,' emphasized their function in 'urban beautification.' This study demonstrates that the community gardens in North America serve their roles as urban amenities and multi-functional public spaces for the entire local population. The implication of the results is that considerations for the social roles the community gardens serve and the spatial elements that allow the space to perform such functions are necessary for the further developments in the community garden research in Korea.

Analysis on Seismic Interpretation for Overseas Large-scale CO2 Storage Considering Geological History Related to Plate Tectonics (판구조론적 역사를 고려한 해외 대규모 이산화탄소 지중저장소 탄성파 해석 결과 분석)

  • Young-Ju Lee;Ha-Yeon Kang;Yun-Gon Park;Ah-Reum Han;Jae-Young Lee;Ju-Won Oh
    • Geophysics and Geophysical Exploration
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    • v.27 no.1
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    • pp.1-22
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    • 2024
  • Carbon dioxide capture utilization and storage (CCUS) techniques have received significant global attention as they are part of efforts to achieve carbon neutrality by 2050. Large-scale carbon dioxide capture and storage (CCS) projects are being actively pursued in North America, the North Sea, the Middle East, and Oceania. Considering the current situation in South Korea, identifying large-scale CCS sites that can secure an annual domestic carbon storage capacity of 30 million tons by 2050 is crucial Therefore, this study analyzed the formation process and geological characteristics of overseas large-scale CCS projects in terms of plate tectonics. We utilized the GPlates program to interpret the formation processes of large-scale CCS projects in North America, the North Sea, Middle East, and Oceania from the perspective of plate tectonics. Additionally, we investigated the geological structure of the CO2 storage layer and interpreted seismic imaging results obtained from each CCS site. This study will help identify a domestic large-scale CCS site.

A coupled model simulation of the Last Glacial Maximum

  • Kim, Seong-Jung
    • Proceedings of the Korean Quaternary Association Conference
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    • 2004.11a
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    • pp.37-43
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    • 2004
  • The response of the CCCma coupled climate model to the imposition of LGM conditions is investigated. The global mean SAT and SST decrease by about $10^{\circ}C$ and $5.6^{\circ}C$ in the coupled model. Tropical SST decreases by $6.5^{\circ}C$, whereas CLIMAP reconstructions suggest that the tropics cool by only about $1.7^{\circ}C$, although the larger tropical cooling is consistent with the more recent proxy estimates. With the incorporation of a full ocean component, the coupled model gives a realistic spatial SST pattern, capturing features associated with ocean dynamics that are seen in the CLIMAP reconstructions. The larger decrease of the surface temperature in the model is associated with a reduction in global precipitation rate (about 15%). The tropical Pacific warm pool retreats to the west and a mean La $Ni\tilde{n}a$-like response is simulated with less precipitation over the central Pacific and more in the western tropical Pacific. The more arid ocean climate in the LGM results in an increase in SSS almost everywhere. This is particularly the case in the Arctic Ocean where large SSS increase is due to a decrease in river discharge to the Arctic Ocean associated with the accumulation of snow over the ice sheet, but in the North Atlantic by contrast SSS decreases markedly. This remarkable reduction of SSS in the North Atlantic is attributed to an increase in fresh water supply by an increase in discharges from the Mississippi and Amazon rivers and an increase in P-E over the North Atlantic ocean itself. The discharges increase in association with the wetter LGM climate south of the Laurentide ice sheet and in South America. The fresh water capping of the northern North Atlantic results in a marked reduction of deep convection and consequently a marked weakening of the North Atlantic overturning circulation. In the LGM, the maximum overturning stream function associated with the NADW formation decreases by about 60% relative to the control run, while in the Southern Ocean, oceanic convection is stronger in the LGM due to reduced stratification associated with an increase in SSS and a decrease in SST and the overturning stream function associated with the formation of AABW and the outflow increases substantially.

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Burqanism from the Origin of the Pastoral Nomadic Koryo Region and the Vision of Korean Livestock Farming (고려의 원시영역 유목초지, 그 부르칸(불함)이즘과 한국축산의 비전)

  • Chu Chae Hyok
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.25 no.1
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    • pp.71-82
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    • 2005
  • Khori(高麗) refers to the Chaabog(reindeer) that live on lichens(蘚) on Mt. Soyon(鮮) in which pastures are the cold and dry plateau of North Eurasia. Thus, the origin region of the Khori or Koguryo that are the ancestors of the reindeer-herding pastoral nomads(馴鹿 遊牧民) can be said to be the Steppe-Taiga-Tundra pastoral areas of North Eurasia and North America. When the pastoral nomads moved on to the great mountain(大山) zone of the Jangbaek(長白) to the Baekdu(白頭) Mountains, they could have been in contact with pastoral farmers or agricultural farmers living there and they became the farmers remaining on agricultural farms. They were the Koryo people, the ancestors of Korea. Staying in one place, they gradually forgot the origin of their reindeer-herding pastoral nomadic history in the Northwest area of Mt. Soyon, the small mountain(小山) zone of the Steppe-Taiga-Tundra pastoral areas. In other words, they lost their identity as reindeer-herding pastoral nomads when they entered the agricultural area after leaving the pastoral area. However, since their basic genes had already formed when they lived on the cold and dry plateau of North Eurasia, it is possible to study their pastoral nomadic history focusing on 'the minority living in the broad area(廣域少數)', by utilizing highly advanced biotechnological science and focusing on genes and information technology innovation, and removing various past hindrances in research. Therefore, it is not so difficult to restore the reindeerherding pastoral nomadic history of the Koguryo(高句麗) people and secure their pastoral nomadic identity, of which the first steps have already been taken into their historical stages. The Eurasian continent and the Korean peninsula, especially the cold and dry plateau of North Eurasia and the Korean peninsula have been closely related to each other ecologically and historically. They can never be a separate space at all. The Eurasian continent lies horizontally east to west and thus, the continent forms an isothermal zone. Also, since the time of producing their own foods, it was relatively easy for people with their technology to move to other places owing to the pastoral nomadic characteristic of mobility. Unlike the Chungyen(中原) region, western Asia and the regions covering the Siberia-Manchu-Korean peninsula where food production revolution was first made were connected to the Mongolian lichens route(蘚苔之路: Ni, ukinii jam) and steppe roads. Although the ecological conditions of nature have changed a bit throughout a long history, it was natural for the many tribes in North Asia living on the largest Steppe-Taiga-Tundra area in the world to have believed 'the legends related to animals in relation to their founders and ancestors(獸祖傳說)'. Assuming that Siberian tigers and the tigers living on Mt. Baekdu were connected ecologically and genetically because of the ecological characteristics of the animals, and their migration from plateau to plateau, we would suspect that the Chosun(朝鮮) tribe living on Mt. Baekdu were ethnically and culturally more closely connected to the farther removed Ural-Altai tribes that lived on the cold and dry plateau region than to the Han(i14;) tribe who lived in Chungyen(中原) that was close to Mt. Baekdu. More evidence is the structure of the Korean language which has the form of 'Subject + Object + Verb', which is assumed to have originated from the speedy lifestyle of the reindeer-herding pastoral nomads. The structure is quite different from that of the Han(漢) language, which is based on agricultural life. Also, it is natural for reindeer riding reindeerherding pastoral nomads or horse-riding sheep-herding pastoral nomads(騎馬, 羊遊牧民) to have held military and political power over the region and eventually to have established an ancient pastoral nomadic empire in the process of their conquest of agricultural regions. The stages for founding global empires in the history of mankind maybe largely divided into two, in terms of ecological conditions and occupations. They are the steppes and the oceans. Of course, the steppe-based empires were established based on the skills to deal with horses and the ability to shoot arrows while riding horses, along with the use of iron ware in the 8th century BC. The steppe-based empires became the foundation for an oceanic empire, which could have been established by the use of warships and warship guns since the 15th Century. Based on those facts, we know that Chosun, Puyo(夫餘), and Koguryo are the products of a developmental process of pastoral nomadic empires on the steppes. Maybe we can easily find the pastoral nomadic identity of the Koguryo more than we expected when we trace the origins and history of the Korean tribe living in the pastures located in the northwest area of Mt. Jangbaek by focusing on pastoral nomadic mobility and organization just as we have investigated the historic origins of Anglo-Saxons in America by focusing on the times before the 15th Century. In the process, we should keep in mind that English culture originated from the Industrial Revolution and was directly delivered to the American continent, although America was far from England and was not an intermediate point on long sojourns either. Further, American culture came back to England in a more advanced form later. The most important thing currently to be resolved is to cause Koreans to look back on their own history in a freer way of thinking and with diverse, profound, and sharp insight, taking away the old and existing conventional recognition that is entangled with complicated interests with Korean people and other countries. The meanings of Chosun, Khori, and Solongos have been interpreted arbitrarily without any historic evidence by the scholars who followed conventional tradition of fixed-minded aristocrats in an agricultural society. If the Siberian cultural properties of the stone age, the earthenware age, the bronze age, and the iron age are analyzed in such a way, archaeological discovery will never be able to contribute to the restoration of the Koguryo's pastoral nomadic identity. One should transcend the errors that tend to interpret the cultural properties discovered in the pastoral nomadic regions as not being differentiated from those of agricultural regions and just interpret them altogether from the agricultural point of view. A more careful intention is required in the interpretation of cultural properties of ancient Korean empires that seem to have been formed due to mutual interactions of pastoral nomadic and agricultural cultures. Also, it is required that the conventional recognition chain of 'reverse-genes' be severed, which has placed more weight on agricultural properties than pastoral nomadic ones, since their settlement on agricultural farms was made after the establishment of their ancient pastoral nomadic empires. There is no reason at all to place priority on stoneware, earthenware, bronze ware, and iron ware than on wooden ware(木器) and other ware which were made of animal skins(皮器), bones and horns(骨角器), in analyzing the history in the regions of reindeer or sheep pastures. Reading ancient Korean history from the perspective of pastoral nomadic history, one feels strongly the instinctive emotions to return to the natural 'mother place'. The reindeer-herding pastoral nomadic identity of the Koguryo people that has been accumulated in volumes in their genes and hidden deep inside and have interacted organically could be reborn with Burqanism(Burqan refers to 不咸 in Chinese), which was their religion by birth and symbolized as the red willow(紅柳=不咸). The mother place of the Koguryo's people is the endless vast green pastures of North Eurasia and North America, where we anticipated the development of Korean livestock farming following the inherent properties in the genes of the reindeer-herding pastoral nomads with Korean ancestors. We anticipate that the place would be the core resource that could contribute to the development of life of living creatures following the inherent properties of their genes and biotechnological factors. In other words, biotechnology used for a search for clues on the well-being of humans could be the fruit brought by Burqanism of the Koguryo people and the fruit of the globalization of Korean livestock farming. It is the Chosun farmer in China come from the vast nomadic reindeer pastures of North Eurasia that resolved the food problem of a billion Chinese people with lowland paddy rice seeds (水稻) by transforming Heilongjiang Province(黑龍江省) into an oceanic lowland paddy rice field(水田). Even Mao Tse-tung(毛擇東) could not resolve the food problem by his revolution campaigns for tens of years. Today is the very time that requires the development of special livestock farming following the inherent properties of the ancient Korean reindeer-herding pastoral nomads that respected the dignity of life on the cold and dry plateau of North Eurasia and the America continent. I suggest that research should be started from the pastures of the Dariganga Steppe in East Mongolia that was the homeland of Hanwoo(韓牛) and the central horse-herding steppe place(牧馬場) of Chingis Khan's Mongolia. The Dariganga Steppe is awash with an affluent natural environment for pastoral nomadic living however, the quality of life of the pastoral nomads there is still low. I suggest we Koreans, the descendents of the Koguryo, should take our first steps for our livestock farming business project and develop the Northern nomadic pastures, here at the pastures of the Dariganga Steppe, which is the Mongolian core place of state-of-the-art technology for military weapons.