Angular resolution enhancement technique for diffusion-weighted imaging (DWI) using predicted diffusion gradient directions

Lee, Mun Bae,Kim, Yeon Hyang,Jahng, Geon-Ho,Kwon, Oh-In Elsevier 2018 NeuroImage Vol.183 No.-

<P><B>Abstract</B></P> <P>Anisotropic diffusion MRI techniques using single-shell or multi-shell acquisitions have been proposed as a means to overcome some limitations imposed by diffusion tensor imaging (DTI), especially in complex models of fibre orientation distribution in voxels. A long acquisition time for the angular resolution of diffusion MRI is a major obstacle to practical clinical implementations. In this paper, we propose a novel method to improve angular resolution of diffusion MRI acquisition using given diffusion gradient (DG) directions. First, we define a local diffusion pattern map of diffusion MR signals on a single shell in given DG directions. Using the local diffusion pattern map, we design a prediction scheme to determine the best DG direction to be synthesized within a nearest neighborhood DG directions group. Second, the local diffusion pattern map and the spherical distance on the shell are combined to determine a synthesized diffusion signal in the new DG direction. Using the synthesized and measured diffusion signals on a single sphere, we estimate a spin orientation distribution function (SDF) with human brain data. Although the proposed method is applied to SDF, a basic idea is to increase the angular resolution using the measured diffusion signals in various DG directions. The method can be applicable to different acquired multi-shell data or diffusion spectroscopic imaging (DSI) data. We validate the proposed method by comparing the recovered SDFs using the angular resolution enhanced diffusion signals with the recovered SDF using the measured diffusion data. The developed method provides an enhanced SDF resolution and improved multiple fiber structure by incorporating synthesized signals. The proposed method was also applied neurite orientation dispersion and density imaging (NODDI) using multi-shell acquisitions.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Novel method to improve angular resolution of DWI signals is proposed. </LI> <LI> The method is based on local diffusion pattern maps of diffusion MR signals on a single and/or multi shells. </LI> <LI> The method provides an enhanced SDF resolution and improved multiple fiber structures. </LI> <LI> The proposed angular resolution improvement is achieved without increasing MR scan time. </LI> </UL> </P>

신제품 및 서비스에 있어 이분조각 Bass모형에 의한 확산 패턴 분석

홍석기(Seok-Kee Hong),홍정식(Jung-Sik Hong) 대한산업공학회 2010 산업공학 Vol.23 No.4

The Bass model is the most widely used model in research of new product diffusion because it presents a nice explanation on the diffusion process of new products. However, it has a limitation that its performance of fitness is lower as the available data become less and also, the diffusion curve is bell-shape and so, it can not represent the various diffusion patterns. Recently, a two-pieces Bass model is developed and applied to analyze diffusion of 10 products. The results are encouraging in terms of fitness. However, diffusion pattern is not dealt with in the paper. In this paper, analysis of diffusion pattern is in depth addressed in two-pieces Bass model. It is shown that the diffusion curves are divided into 3 types with respect to the peak adoption rate and each type is divided into 2 types further. Takeoff time of a diffusion process is analyzed by using the inflection point and regime-change time where it represents the point that imitation and innovation parameters change. Empirical studies for 68 products(28 domestic products and 40 USA products) are performed to analyze the diffusion pattern. Findings are that diffusion patterns of all products except 1 USA product show typeⅠ and regime-change time becomes shorter as the introduction time of the product is later in domestic products and regime-change time can be regarded as a takeoff time in 47% of total 68 products.

모습이 특이한 연화문에 관한 연구

조원교 동방문화대학원대학교 문화예술콘텐츠연구소 2024 문화와예술연구 Vol.24 No.-

연화문의 모습은 자연 상태와 가깝고 닮은 경우와 닮지 않은 먼 모습 즉 모습이 특이한 경우로 크게 구분할 수 있다. 우리 겨레는 이 논문에 소개하는 모습이 특이한 연화문들도 여느 연화문과 더불어 삼국시대 초(기원후 1세기경)부터 약 2천여 년간 보편적으로 다양하게 줄곧 표현하였다. 이 연화문들은 불교 전래와 함께 유입된 외래 표현이 아니다. 원(原) 중국 역사문화강역(현재 중국 섬서성·하남성 일대)으로부터 영향받은 표현도 아니다. 우리 겨레의 원(原) 역사문화강역 안 신석기시대 또는 고조선(청동기)시대부터 시작된 고유의 표현들을 계승 발전시킨 모습이다. 우리 조상들은 이들을 분명하게 연화문으로 인식하며 표현하였다. 이는 이 문양들이 모습이 다른 연화문들과 대부분 함께 사용되거나 서로 연결되어 있음에서, 모습이 다른 연화문을 대신하거나 대치한 경우가 많음 등에서 내린 결론이다. 현재의 학계에서는 이 모습이 특이한 연화문들을 연화문으로 여기지 않고 있다. 추상적 문양·기하학적 문양이라 단정하거나 심지어 전혀 상관없는 잘못된 이름들을 부여하였다. 모습이 특이한 연화문들은 첫째 기와 생장(화생 포함)을 담고 표현하는 과정에서, 둘째 삼국시대 이전의 여러 문양을 계승, 수용하면서 다양하게 도안되며 더욱 확산되었다. 이 논문을 계기로 우리 겨레의 대표 표현인 다양한 연화문이 명확하게 인식, 이해되고 널리 전달되었으면 하는 마음 간절하다. 오래전부터 중국에도 전파되어 큰 영향을 끼쳤다는 위대한 역사적 사실도 함께 널리 알려지기를 바라는 바이다. Korean people have expressed unique lotus patterns in a variety of ways along with other lotus patterns for about 2,000 years since the beginning of the Three Kingdoms period around the 1st century AD. These unique lotus pattern are not foreign expression introduced with the introduction of Buddhism. Nor are they any expression conveyed by the original Chinese historical and cultural region, currently located in Shaanxi and Henan provinces of China. They were created solely by inheriting unique expressions developed from the Neolithic Age or Gojoseon Period, Bronze Age, within the original Korean historical and cultural region. Our ancestors clearly recognized these unique patterns and expressed them in lotus patterns. This study is a conclusion drawn from many cases in which these unique patterns are mostly used together with other lotus patterns or are connected to each other, and the entire shape replaces other lotus patterns or appears transformed into a different form. Until now, academic researches do not regard these unusual lotus patterns as lotus patterns. They either assumed it was an abstract pattern or a geometric pattern, or even gave it completely unrelated, incorrect names. The unique lotus pattern spread further as it was designed in a variety of ways, firstly in the process of containing and expressing gi(氣, vitality) and growth(including the birth in lotus) and secondly, by accepting various patterns before Three Kingdoms period. It is hoped that through this study, the unique lotus pattern will be clearly identified and that the fact that it was spread throughout Chinese region and had a great influence on the expression of the lotus flower will also be known.

1920,30년대 인천부(仁川府) 전화 미디어의 확산구조

윤상길(Yoon, Sang-gil) 인천대학교 인천학연구원 2009 인천학연구 Vol.11 No.-

The purpose of this article is to look at the spatial diffusion of telephone system in In-cheon during 1920~30s. For this purpose, this article discussed historical development of technological and institutional elements of telephone system during colonial period. Telephone enterprises established by the Government-General of Korea(GGK) in an administrative district of In-cheon was stagnated by two primary factor. This two primary factor was as follows. The first factor was problems of telephone administration such as the adjustment of partitions in telephone subscription district. Actually, the definite adjustment of partitions in telephone subscription district of In-cheon was accomplished in 1919. The second factor was technological problems such as obsolete telephone equipments. Telephone sets over seven thousand couldn't be accommodated before a single magneto switchboard was changed into a multiple magneto switchboard in December, 1923. Nonetheless, the diffusion of telephone among Japanese people was accomplished in comparatively fast pace. Japanese people owned telephone at the rate of three or four household to one. But, the diffusion of telephone among Korean people was very slow, showing a ratio of one hundred household to one. Also, the diffusion of telephone in In-cheon of 1920~30s was biased in terms of occupational distribution. About 90% of telephone owner were merchants and industrialists. Also about 33~4% of telephone owner of merchants and industrialists were forwarding agents, grain brokers, grain millers, and restaurant owner. On the other hand, the ethno-biased diffusion of telephone was intertwined with the space-biased diffusion. Overall spatial diffusion of telephone in In-cheon was accomplished in two ways. One was pattern of diffusing without particular rules in a densely populated district of telephone owner. The other was pattern of diffusing according a main road in a loosely populated district of telephone owner. As a result, telephones of Korean people were mainly located in regions such as 'Naeri'(內里), 'Yongri'(龍里), 'Oeri'(外 里), where Korean rich person lived. telephones of Japanese people were diffused with a form of a concentric circle. Central region of this concentric circle was as follows: 'Hang-Jeong'(港町), 'Hae-An-Jeong'(海岸町), 'Bon-Jeong' (本町), 'Joong-Jung'(仲町), 'Bin-Jeong'(濱町), 'Shin-Jeong'(新町), 'Goong-Jeong'(宮 町).

中國 陝西省 北朝造像에 관한 硏究 -영평년간永平年間 도교상과 평행선平行線 문양을 중심으로-

서남영 덕성여자대학교 인문과학연구소 2022 인문과학연구 Vol.- No.34

In this paper the interpretation of the Taoist image of the Yeongpyeong year (永平年間, 508-511 AD) in the Eisei Bunko Museum of Japan as a 'transitional Taoist image' and the parallel lines pattern unique to the Shǎnxī (陝西) region in the first half of the 6th century (which was called the ‘FùXiàn 鄜縣 style’) were examined. I examined the transmission process and iconographic characteristics of the Taoist image during the Yeongpyeong year through the recently discovered text “Zozoshokakuki(造像所獲記)” and data from the 1900s. The range and origin of the parallel lines pattern, which is commonly found in statues, were also examined. Through a review of the monolithic, four-sided, and grottoes that contain the parallel lines pattern - which has been mentioned as the representative style of statues in the Shǎnxī region - it was possible to confirm the intensive use of this style in the first half of the 6th century (500-520 AD) particularly in Líntóng(臨潼), YàoXiàn(耀縣), and Fùpíng(富平) of the greater Shǎnxī region. However, the use of the parallel lines pattern was not confirmed until the end of the 5th century; its appearance increased from the beginning of the 6th century. In addition, the way the parallel lines pattern was used changed periodically. Initially the parallel lines were expressed in small areas of the artwork, but by around 510 AD, the pattern was seen throughout the entire piece. From only being used to describe the texture of clothing, the parallel lines pattern grew in popularity and was later observed in the representations of other objects including the sun and the moon, dragons, and lions. Therefore it is more appropriate to call the parallel lines pattern ‘the style around the Xi'an(西安)’ as opposed to the ‘FùXiàn(鄜縣) style’. Also the parallel lines pattern that was popular on Taoist and Buddhist images made in and around Xi'an region in the early 6th century could be found in the sculptural expressions of the stone reliefs from the Han Dynasty. This pattern, which was observed in the traditional iconography favored by the Han Chinese, is believed to have regained popularity in the early 6th century. In this way, it can be seen that the Han Dynasty stone reliefs had a multifaceted influence on sculptures (such as the Taoist and Buddhist images) made in the suburbs of the Xi'an region in the first half of the 6th century. Therefore, the inspection of the Taoist images of the Yeongpyeong year revealed that the parallel lines pattern was a unique and traditional technique needed to shape the Taoist image in the first half of the 6th century in and near the Xi'an region. 본고에서는 일본의 에이세이永青 문고 미술관이 소장하고 있는 영평년간永平年間(508~511년) 도교상에 관한 ‘과도기적 도교상’으로서의 해석과 기존의 ‘부현鄜縣양식’이라고 불렸던 6세기전반섬서지역 특유의 평행선 문양에 관해서 살펴보았다. 필자는 신 자료인 “조상소획기造像所獲記”와1900년대 초기 자료를 통해 영평년간 도교상의 전래 경위와 도상적인 특징을 살펴보고, 본상과더불어 6세기전반 섬서지역 조각상에 공통적으로 확인되는 평행선平行線 문양이 유행한 범위와유래에 관해서도 살펴보았다. 특히 섬서지역 조각상의 대표적인 양식으로 언급되어 온 평행선 문양이 확인되는 단독상과 사면상, 석굴의 검토를 통해서 섬서지역 중에서도 임동臨潼과 요현耀縣, 부평富平을 중심으로 하는서안과 그 부근 지역권에서 확인된다는 점과 시기적으로는 6세기 전반(500~520년)에 집중적으로제작된 경향을 알 수 있었다. 다만 서안과 그 부근에서는 5세기말까지는 평행선이 확인되지 않다가6세기 초부터 증가하는 것을 확인할 수 있었다. 또한 시기별로 처음에는 부분적으로 평행선이 표현되다가 510년경에 이르면 착의 전체에 흐르는 것처럼 묘사되고, 최종적으로는 본존이나 협시, 천인상의 옷 주름을 표현하는 착의에만 한정적으로 쓰인 것이 아니라 일월, 용, 사자 등의 표면을 장식하는 하나의 문양으로 크게 유행한 것을 알 수 있었다. 따라서 평행선 문양에 관해서는 기존의‘부현鄜縣양식’이라는 용어보다는 ‘서안주변 양식’으로 부르는 것이 타당하다는 결론에 이르렀다. 또한 6세기 초에 서안과 근교에서 제작된 도교상과 불상에 유행한 평행선 문양의 유래에 관해서는, 한대 화상석에서 확인되는 석조의 조각 표현에서 공통점을 찾을 수 있었다. 또한 한민족이애호했던 전통적인 도상이 증가하는 경향에 관해서도 화상석에서 표현된 주요 소재가 6세기 전반에 다시 유행한 것으로 추정했다. 이와 같이 한대의 화상석은 6세기전반 서안 근교에서 제작된도교상과 불상 등의 조각에 다각적으로 영향을 끼친 것을 알 수 있으며 그 요인으로는 서안을 중심으로 하는 지역의 복고주의적인 제작 경향이 반영된 현상으로 해석했다. 따라서 6세기전반 서안을중심으로 한 지역에서 평행선 문양은 도교상이 중국에서 최초로 형상화 될 때 필요했던 전통성과독자성에 부합하는 전통적인 제작기법으로, 이러한 초기의 현상을 바로 영평년간 도교상을 통해확인할 수 있다.

PATTERN FORMATION FOR A RATIO-DEPENDENT PREDATOR-PREY MODEL WITH CROSS DIFFUSION

M. SAMBATH,K. BALACHANDRAN 한국산업응용수학회 2012 Journal of the Korean Society for Industrial and A Vol.16 No.4

In this work, we analyze the spatial patterns of a predator-prey system with cross diffusion. First we get the critical lines of Hopf and Turing bifurcations in a spatial domain by using mathematical theory. More specifically, the exact Turing region is given in a two parameter space. Our results reveal that cross diffusion can induce stationary patterns which may be useful in understanding the dynamics of the real ecosystems better.

축소 모의된 구획 화재의 흘림 실험에 대한 인화성 액체의 화재 패턴 해석

조희수,최충석 한국화재소방학회 2014 한국화재소방학회논문지 Vol.28 No.3

The purpose of this study is to analyze the flame propagation speed, radiation range, diffusion pattern and combustioncompletion time of a fire by filling a divided space with single combustible substance. It was found that the flame propagationspeed was the fastest (0.2 s) for kerosene and the lowest (82.1 s) for alcohol. In the case of paint thinner, it took19.0 s for the flame to reach its peak at the fastest speed after ignition while in the case of alcohol, it took 138.6 s for theflame to reach its peak at the lowest speed. In the case of the combustion of 200 ml of flammable liquids, the combustioncompletion time was 79.9 s for paint thinner, which is the shortest, 135 s for gasoline, 170 s for kerosene, 231.4 s for dieseland 337.0 s for alcohol. In addition, when flammable liquids are combusted, the lower part of the flame is governed bylaminar flow pattern and the upper part of the flame showed turbulence pattern. In the case of a test performed for beanoil, it could be seen that if the fire source was removed, the flame was automatically extinguished without further combustionand that white smoke was generated due to incomplete combustion. 본 연구는 구획된 공간에 인화성 단일 물질을 채우고 착화된 화염의 전파 속도, 방사 범위, 확산 패턴 및 연소 완료시간 등을 해석하는 데 있다. 화염의 전파 속도는 등유가 0.2 s로 가장 빠르고, 알코올이 82.1 s로 가장 늦었다. 화염이착화된 후 화염이 가장 빠르게 최성기에 도달한 것은 시너이었고 19.0 s가 걸렸다. 그리고 가장 늦은 것은 알코올로138.6 s로 측정되었다. 인화성 액체 200 ml가 연소 완료되는 시간은 시너가 79.9 s로 가장 짧았고, 가솔린 135 s, 등유170 s, 경유 231.4 s, 알코올 337.0 s 등으로 측정되었다. 그리고 인화성 액체가 연소될 때 화염의 하단 부분은 층류 패턴이 지배하였고, 상단 부분은 난류 패턴을 나타냈다. 대두유의 실험에서 착화시킨 화원을 제거하면 화염은 자연 소화되어 연소가 진행되지 않았고, 불완전 연소에 따른 흰색의 연기가 발생하는 것을 알 수 있었다.

개봉 규모와 수익성에 따른 영화의 분류와 확산 패턴 분석

김태구(Taegu Kim),홍정식(Jungsik Hong) 대한산업공학회 2013 대한산업공학회지 Vol.39 No.5

Motion picture industry is one of the most representative fields in the cultural industry and has experienced constant growth both worldwide and within domestic markets. However, little research has been undertaken for diffusion patterns of motion pictures, whereas various issues such as demand forecasting and success factor analysis have been widely explored. To analyze diffusion patterns, we adopted extended Bass model to reflect the potential demand of movies. Four clusters of selected movies were derived by k-means clustering method with criteria of opening strength and profitability and then compared by their diffusion patterns. Results indicated that movies with high profitability and medium opening strength are most significantly influenced by word of mouth effect, while low profitability movies display nearly monotonic decreasing diffusion patterns with noticeable initial adoption rates and relatively early peak points in their runs.

온라인 구전정보특성이 구전수용과 확산에 미치는 영향 : 소비자 정보수용유형을 중심으로

성태경 ( Tae Kyong Sung ),홍상진 ( Sang Jin Hong ) 대한설비관리학회 2015 대한설비관리학회지 Vol.20 No.4

Recently internet is rapidly spreading and generalized. And due to the growing popularity of the Internet, Online WOM(Word Of Mouth) have been playing an important role as a critical factor in evaluating product features. Therefore, many firms are taking advantage of online consumer review as a new marketing tool. The purpose of this study was to clarify the impact of Online WOM``s information characteristics(consensus, vividness, community interaction) on WOM acceptance and diffusion focusing on technology acceptance pattern of Rogers(innovators, early Adopters, early Majority). As the result of analyses, it has been found out that consensus, vividness, community interaction of Online WOM``s information characteristics affect WOM acceptance and diffusion and WOM acceptance effect on diffusion. Lastly, there is a difference depending acceptance pattern of customer.

What Drives Management Accounting Innovations? A Survey of Activity-Based Costing Journal Publications

이윤기,Josie McLaren,장대일,Lana Y.J. Liu 단국대학교 미래산업연구소 2024 산업연구 Vol.48 No.2

The purpose of this study is to examine the driving forces behind the diffusion of an important management accounting innovation, activity-based costing (ABC). Driving forces are analyzed within five main aspects (volume, journal field, journal type, author type, and content type) through a survey of English-language journal publications relating to ABC and its recent iteration, Time-Driven Activity-Based Costing (TDABC), between 1988 and 2019. Employing linear regression and Mann-Kendall statistical analyses, our results find some diffusion patterns. First, ABC/TDABC initially appears in business management then spread to non-business management fields, in particular to the bio/medical field. Second, driving forces behind ABC/TDABC diffusion have changed. At the beginning of the spread of ABC (1988-2003), it shows a push by academics and consultants. However from 2004 to 2019, there is a clear pull by practitioners, in particular medical doctors in the bio/medical field who see a need for this innovative tool. Third, academics and consultants attempt to spread ABC/TDABC to generate more research activities and business, whilst practitioners’ quests for ABC/TDABC are driven by their intrinsic needs and external demands. The longitudinal picture of ABC diffusion may shed light on how to enable such a management accounting innovation to achieve its long term success.