• Korean Journal of Veterinary Research
• /
• v.32 no.4
• /
• pp.497-510
• /
• 1992

This study was attempted to comparative investigate the types and regional distribution of the endocrine cells in several vertebrates immunohistochemically using seven antisera. From carp pancreas could be observed 4 types which are insulin-, glucagon-, som- and BPP-immunoreactive cells. Insulin-immunoreactive cells were mainly distributed at the periphery and a few cells occupied the central region of the islets. Glucagon-immunoreactive cells were distributed at the periphery of the islets, and som - and BPP-immunoreactive cells were located at the central region. From frog pancreas could be observed 4 types which are insulin-, glucagon-, som- and BPP-immunoreactive cells. Insulin-immunoreactive cells were distributed throughout the islets. Som-immunoreactive cells were distributed at the periphery of the islets, and glucagon- and BPP-immunoreactive cells were found as single cell or as small groups located between the pancreatic acini. From snake pancreas could be observed 3 types which are insulin-, glucagon- and som -immunoreactive cells. Insulin-immunoreactive cells were distributed throughout the small islets, and they also were scattered at the periphery of the large islets. Glucagon-immunoreactive cells were distributed at the periphery of the islets, whereas som-immunoreactive cells were occupied the central region. From Ogolgae pancreas could be observed 4 types which are insulin-, glucagon-, som-and BPP-immunoreactive cells. Insulin-immunoreactive cells were distributed throughout the small islets, but at the periphery of the large one. Glucagon- immunoreactive cells were distributed at the periphery of the small islets and in the large islets showed scattering entired. Som-immunoreactive cells were distributed at the periphery of the small islets and in the large islets were located at the central region. A small numbers of BPP-immunoreactive cells were located at the periphery of the small islets and the exocrine regions. From the pancreas of the Korean native goat could be observed 6 types which are insulin-, glucagon-, som-, BPP-, 5-HT- and porcine-CG-immunoreactive cells. Insulin-immunoreactive cells were distributed throughout the islets. Som-immunoreactive cells were located at the periphery of the islets, but a tew were scattered at the central region of islets and in the epithelium of the secretory duct. Glucagon-, BPP-, 5-HT- and porcine CG-immunoreactive cells were distributed at the periphery of the islets. These findings indicated that the regional distribution patterns and cell types of pancreatic endocrine cells in vertebrates varies considerably among phylogenetically different vertebrates.

• Korean Journal of Heritage: History & Science
• /
• v.51 no.2
• /
• pp.108-123
• /
• 2018

This paper focuses on the relationship between center and periphery by discussing the circulation of rare resources, such as bronze, stamped hard pottery, and proto-porcelain. The discussion includes two parts: the internal Shang culture region and the region outside of Shang. Within the Shang culture region, all the resources mentioned above were brought from different places to the Panlongcheng site and then transferred to Zhengzhou Shang city. On the other hand, they also produced and consumed the resources in a special way, which indicates a certain degree of independence. Outside the Shang region, bronze products and maybe even raw copper resources were circulated from Zhengzhou Shang city to the Chengyang site, while stamped hard pottery and proto-porcelain were transferred to Zhengzhou through the Panlongcheng site. Resource circulation was bi-directional. Thus, this resource circulation was one of the key factors to building the relationship between center and periphery.

• Journal of the Economic Geographical Society of Korea
• /
• v.7 no.2
• /
• pp.137-156
• /
• 2004

This paper investigates the current situation of the Gyeonggi border region, which demonstrates the distorted political and economic realities of Korea, in order to gain the basic information that enables the comprehensive understanding of the Gyeonggi border region. This study has found that the 'Law for Protection of Military Facilities' has limited residents' life and economic activities in the region. And, the 'Law for Planning of the Capital Region' has also became another barrier to development of the region. Finally, the analysis of the region's economic condition showed that these regulations have made the Gyeonggi border region a backward periphery.

• Proceedings of the IEEK Conference
• /
• 2000.09a
• /
• pp.675-678
• /
• 2000

This paper presents a parametric line equation on the log-polar mapped plane to detect the straight lines in an original image. The log-polar edge image used in Hough transform is constructed by combining the edge images of both fovea and periphery. The foveal edge image detected by a Sobel mask on the Cartesian plane is transformed to the log-polar plane by forward mapping but the edge detection of the peripheral region is obtained by directly applying the newly developed mask to the log-polar plane. This paper also proposes a analytic method then determining a border between the fovea and the periphery regions.

• The Korean Journal of Ecology
• /
• v.18 no.1
• /
• pp.31-41
• /
• 1995

Floral analysis about vegetation of Kimpo landfills and its periphery region was carried out. The study area was defined to a square $(81km^2)$ of which center was located at 250m in front of Andongpo, Komdan-myon, Kimpo-gun in the northwest part of the Kyunggi Province. This study was accomplished by analyzing five qualitative traits such as ecological strategy, reproductive strategy, distribution type, native/foreign division and life-form throughout actual investigation of the flora. The flora was composed of 536 taxa which comprise 105 families, 343 genera, 458 species, 1 subaspecies, 70 varieties and 7 forms (including 92 species of horticultural plant). Lythrum salicaria community, Spiraea salicifolia community, ottelia alismoides community and woods of Alnus japonica were recorded ？ 새 retrictive distribution according to habitat characteristics. Owing to severe anthropogenic interferences such as construction of the Kimpo landfills in the study areas, a high proportion of ruderal plants and neophytes in the floral composition was recognized. The proportion of individual distribution type and therophyte was very high throughout whole study areas, and plant communities in the reclaimed areas were characterized by high proportion of phalanx plant species. Analysis of the correlations between meshes with ecological traits of plant species showed that Kimpo landfills and its periphery region was divided into two vegetation types, coastal type and inland type, as a result of possible saline effects.

• Journal of the Korean association of regional geographers
• /
• v.5 no.1
• /
• pp.77-90
• /
• 1999

This paper aims to understand the changing characteristics of the Kumi region as a locality in Korea through the regional geography of the world-system approach. To illustrate the changing regional characteristics, we analyzed the economic characteristics or position of the Kumi region within the world-economy and its spatial structure with three divisions of Korean capitalist periods: the Japanese colonial period ($1910{\sim}1945$), the social chaos period ($1945{\sim}1960$), and the economic development period ($1960{\sim}$present). In the Japanese colonial and social chaos periods, as Korean society was incorporated into the peripheral zone within the world-System (world-economy), Kumi also was made into a peripheral agricultural area. As a result, the Kumi region shaped the rural spatial structure without an urban center or regional dominant center. In the development period, influenced by the manufacturing-centered economic policy which boosted Korea as a semi-periphery within world-economy, Kumi also was developed into an industrial region(or semi-periphery) with the establishment of the Kumi electronic and textile industrial complex. This industrialization transformed the rural spatial structure of Kumi into a core (urban center)-periphery (rural area) structure. As we identified above, the regional geography of the world-system approach turned out to be a useful methodology to study a locality or internal region. Therefore we should make efforts to study such regions through the regional geography of the world-system approach.

• East Asian Economic Review
• /
• v.26 no.3
• /
• pp.205-225
• /
• 2022

Different types of corporate ownership may affect the environment among firms and could influence the decisions of new entities in the region. This study determines the role of state-owned enterprises (SOEs) in hindering new foreign manufacturing firms in the Yangtze River delta (YRD). The negative binomial regression is used for city-sector level data and the following points summarize the results: Firstly, the unique privileges that SOEs enjoy alongside governmental support create difficulties for foreign firms trying to establish themselves near existing SOEs. Secondly, although core cities are more attractive to foreign firms than peripheral cities, the role of core-periphery reveals that, in spite of all the regional advantages core cities could offer, whenever the share of SOEs is higher, the core-periphery system will have an adverse impact on new foreign firms. In other words, government preference for SOEs can suppress the attraction of foreign start-ups. However, after 2008, the governmental authorities finally succeeded in implementing their promising policy of fair treatment and competition in only the core cities.

• Nuclear Engineering and Technology
• /
• v.42 no.1
• /
• pp.79-88
• /
• 2010

Spent $UO_2$ nuclear fuel discharged from a nuclear power plant (NPP) contains fission products, U, Pu, and other actinides. Due to neutron capture by $^{238}U$ in the rim region and a temperature gradient between the center and the rim of a fuel pellet, a considerable increase in the concentration of fission products, Pu, and other actinides are expected in the pellet periphery of high burnup fuel. The characterization of the radial profiles of the various isotopic concentrations is our main concern. For an analysis, spent nuclear fuels originating from the Yeonggwang-2 pressurized water reactor (PWR) were chosen as the test specimens. In this work, the distributions of some actinide isotopes were measured from center to rim of the spent fuel specimens by a radiation shielded laser ablation inductively coupled plasma mass spectrometer (LA-ICP-MS) system. Sampling was performed along the diameter of the specimen by reducing the sampling intervals from 500 ${\mu}m$ in the center to 100 ${\mu}m$ in the pellet periphery region. It was observed that the isotopic concentration ratios for minor actinides in the center of the specimen remain almost constant and increase near the pellet periphery due to the rim effect apart from the $^{236}U$ to $^{235}U$ ratio, which remains approximately constant. In addition, the distributions of local burnup were derived from the measured isotope ratios by applying the relationship between burnup and isotopic ratio for plutonium and minor actinides calculated by the ORIGEN2 code.

• Journal of the Institute of Electronics Engineers of Korea SP
• /
• v.39 no.4
• /
• pp.455-461
• /
• 2002

This paper presents a new parametric log line equation of polar form for Hough transform in log-polar plane, in which it can remove the well-known unboundedness problem of Hough parameters. Bolduc's method is used to generate a log-polar image dividing the fovea and periphery from a Cartesian image. Edges of the fovea and periphery are detected by using the Sobel mask and the proposed space-variant gradient mask, and are combined in the log-polar plane. The sampled points that might constitute a log line are quite sparse in a deep peripheral region due to severe under-sampling, which is an inherent property of LPM. To cope with such under-sampling, we determine the values of cumulative cells in Hough space by using the space-variant weighting. In our experiments, the proposed method demonstrates its validity of detecting not only the lines passing through both the fovea and periphery but also the lines in a deep periphery.

• Nuclear Engineering and Technology
• /
• v.42 no.5
• /
• pp.576-581
• /
• 2010

KAERI (Korea Atomic Energy Research Institute) fabricated MOX (Mixed Oxide) fuel pellets as a cooperation project with PSI (Paul Scherrer Institut) for an irradiation test in the Halden reactor. The MOX pellets were fitted into fuel rods that included instrumentation for measurement in IFE (Institutt for Energiteknikk). The fuel rods were assembled into the test rig and irradiated in the Halden reactor up to 50 MWd/kgHM. The irradiated fuel rods were transported to the IFE, where ceramography was carried out. The fuel rods were cut transversely at the relatively higher burn-up locations and then the radial cross sections were observed. Micrographs were analyzed using an image analysis program and grain sizes along the radial direction were measured by the linear intercept method. Radial cracks in the irradiated MOX were observed that were generally circumferentially closed at the pellet periphery and open in the hot central region. A circumferential crack was formed along the boundary between the dark central and the outer regions. The inner surface of the cladding was covered with an oxide layer. Pu-rich spots were observed in the outer region of the fuel pellets. The spots were surrounded by many small pores and contained some big pores inside. Metallic fission product precipitates were observed mainly in the central region and in the inside of the Pu spots. The average areal fractions of the metallic precipitates at the radial cross section were 0.41% for rod 6 and 0.32% for rod 3. In the periphery, pore density smaller than 2 ${\mu}m$ was higher than that of the other regions. The grain growth occurred from 10 ${\mu}m$ to 12 ${\mu}m$ in the central region of rod 6 during irradiation.