• Journal of Environmental Science International
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• v.33 no.7
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• pp.477-487
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• 2024

This study aimed to identify the growth environment of Cudrania tricuspidata by analyzing the site environment, soil characteristics, and vegetation structure of the species habitats and to provide basic data for identifying suitable cultivation sites for mass production. The study was conducted on 17 sites in five cities/counties of Gyeongnam and Jeonnam province. It was found that C. tricuspidata habitats were mainly distributed on gentle slopes in the southeast and southwest, with an average altitude of approximately 290 m. The soil of the C. tricuspidata habitats was sandy loam with a high proportion of sand, averaging 73.9%, 4.6%, and 21.5% sand, silt, and clay, respectively. The soil had a pH value of 5.41 (5.20-5.79), organic matter content of 8.2% (3.6-12.6%), total nitrogen content of 0.36% (0.19-0.54%), available phosphorus content of 3.50 ppm (0.95-7.61 ppm), and cation exchange capacity of 15.9 cmol⁺/kg (10.0-20.7 cmol⁺/kg) on average. The vegetation structure analysis showed that C. tricuspidata appeared in the tree layers of regions A (Jinju) and E (Yeosu), but the importance of C. tricuspidata was found to be high in the subtree and shrub layers in all regions. The ecological niche breadth was widest (0.874) in region B (Hadong) and narrowest (0.480) in region E (Yeosu).

• Journal of the korean society of oceanography
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• v.31 no.4
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• pp.217-231
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• 1996

The distribution patterns of the benthic macrofauna of Han Estuary and Kyonggi Bay and the controlling environmental factors were studied at twenty-five stations in spring and fall of 1989. As a result, four biological groups were established as follows : Crassostrea gigas-Balanus reticulatus (Group I), Heteromastus filiformis-Mediomastus californiensis-Lumbrineris spp. -Sternaspis scutata-Tharyx sp. 1-Diopatra bilobata (Group II-A), Haustoriids-Phoxocephalids-Moerella rutila (Group II-B) and Nephtys chemulpoensis (Group II-C in March) and indistinctive group which was composed of common species (II-C in September). Results of the habitat analysis revealed that most of the dominant species showed narrow ranges of habitat niche in March and relatively wide ranges in September. Based on multiple discriminant analysis, the critical environmental factors governing their distributions are salinity in the regions of Yomha and Sokmo Channel in Han Estuary and sediment types in Kyonggi Bay. Also, sediment instability during the rainy season due to run-off was assumed to play a major role in the species composition of the benthic communities and their distribution in the study area.

• Journal of Environmental Impact Assessment
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• v.27 no.6
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• pp.685-694
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• 2018

We measured ecological niche space (ENS) using carbon and nitrogen stable isotope ratios of benthic macroinvertebrates to estimate its applicability for large river assessment. In particular, we compared ENSs of selected macroinvertebrates between upper and lower area of Seungchon Weir in Yeongsan River to estimate the impact of weir on biological community. We also measured basic water quality and community indices including benthic macroinvertebrates index (BMI) to estimate their correlations with calculated ENS. ENS was calculated using the Bayesian Stable Isotope in R statistics (package "SIBER"). The results showed that seasonal variations in water quality and community indices were found, but there was no apparent tendency between upper and lower area of the Seungchon Weir in June (before rainy season) and August (after rainy season). However, ENS of benthic macroinvertebrates markedly decreased across the weir in both June and August regardless of changes in water quality. This means the physical change of the stream due to the weir cause decrease of ecological isotopic niche space of benthic macroinvertebrates regardless of water quality, suggesting physical modification by the weir can affect the interaction between habitat condition and macroinvertebrates. Therefore, the ecological isotopic niche space can be a useful supplementary indicator for the river ecosystem assessment.

• Journal of the Korean Institute of Landscape Architecture
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• v.22 no.2
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• pp.133-157
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• 1994

This study was executed to find out the succession stage and the ecological niche of Lindera erythrocarpa Markino. Four sites were selected by field investigation. They are Jeondungsa and Jeongsusa of Kanghwa Island, Mt. Suri of Anyang and Mt. Gaya of Chungcheongnamdo. They located in the region which have the similar temperature with Seoul region or lower average temperature for winter than that of adjacent Seoul. In the four sites, L, erythrocarpa was appeard in canopy layer at L. erythrocarpa community in Jeondungsa, L. erythrocarpa-Q. serrata, Z. serrata-L. erythrocarpa community in Jeongsusa, Castanea crenata-L, erythrocarpa community, L. erythrocarpa-Q. serrata community in Mt. Gaya and in the rest of the sites, it lives in subtree and shrub layer. And in the four sites but Jeongsusa area, it correspond with Chang(1991)'s study that L. erythrocarpa is dominant species in the site impacted by human. L. erythrocarpa lives with Quercus spp. such as Q. serrata, Q. variabilis, Q. mongolica and Carpinus laxiflora but it's presumably a passing phenomena.

• Journal of Distribution Science
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• v.12 no.5
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• pp.33-40
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• 2014

Purpose - This paper aims to review cold chain management, especially in the pharmaceutical industry, to explore the cold chain process of delivering temperature-sensitive pharmaceutical products, and to identify areas for further development. Research design, data, and methodology - The paper, based on literature review and corporate analysis, reviews the development and status of the cold supply chain system, including its important role in the pharmaceutical industry. Results - Logistics in this field requires more stages than are typically needed. Due to the unique characteristics of the market, few companies can provide the services; currently, only few global companies with large networks and high technologies can afford to do so. Expanding pharmaceutical markets to meet global demand will require cold chain development, especially in "pharmerging" markets. Conclusions - Cold chain is a highly sensitive market in terms of products being carried within the chain that itself is a complex system. However, at the same time, it is a niche market with new opportunities. Hence, a sound cold chain infrastructure is needed to satisfy companies, governments, and customers for both commercial and public reasons.

• Asia pacific journal of information systems
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• v.11 no.3
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• pp.63-89
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• 2001

The purpose of this research is to develop strategic alternatives for the high-tech products development by comparatively studying characteristics of the industry and R&D structures in Korea and the US. Some of the environmental, strategic, organizational and project teams' characteristics are studied. Data were collected from Korea and US high-tech companies through interviews and questionnaires and event analysis method was used to analyze them. The findings are as follows: First, when the level of market concentration is high, cycle time tends to be longer. Therefore, if there are many competitors in the market, new products development should be swift due to competitive pressures. Second, the developmental strategy should be directed toward the existing customers to speed up new products development. That is, a defensive strategy would result in a shorter cycle time and response time compared to a strategy directed to a niche market. Third, when the level of formalization is high, cycle time tends to be shorter. This means that formal procedures for new products idea development or new products development policies shorten new products development time.

• Smart Structures and Systems
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• v.7 no.1
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• pp.27-40
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• 2011

Geopolymer concrete is finding a growing number of niche applications in the field of civil engineering due to its high compressive strength and strength gain rate, retainage of structural properties in elevated temperature environments, chemical stability in highly acidic conditions and environmental benefits. Combining the above mentioned characteristics with induced electrical conductivity, could enable geopolymer cement to serve as a smart and sustainable cementitious material suitable for health monitoring of civil structures. Carbon fibers were added to fresh geopolymer and OPC (ordinary Portland cement) mixes to enhance their electrical conductivities. AC-impedance spectroscopy analysis was performed on the specimens with fiber fraction ranging from 0.008 to 0.8 with respect to the weight of cementitious binder, to measure their electrical resistivity values and to determine the maximum beneficial fiber content required to attain electrical percolation. Experimental observations suggest that CFR-geopolymer cement exhibits superior performance to CFR-OPC in terms of conducting electrical current.

• Journal of Information Technology Applications and Management
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• v.27 no.6
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• pp.31-51
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• 2020

During the last decade, social live streaming service like Periscope, Ustream, and YouNow has developed from a niche market into a mainstream activity. In this media environment, social live streaming service has a tremendous impact on the social behaviors of users. Despite the rapid development, there are a lack of studies to make better understand the media environment changes through social live streaming service. This study adopted an affordances approach that leads us to identify six distinctive social affordances (visibility, accessibility, information sharing, social interaction, role-taking, interactive revenue) for user engagement in social live streaming service. Specifically, this study explores the impact of social affordances on perceived flow, followed by user engagement including passive and active engagement. Empirical data analysis with 258 questionnaires suggests that social affordances affected users' flow perception, and flow has an effect on active as well as passive engagement. Contrary to the expectation in a hypothesized research model, only the impact of accessibility on flow was rejected.

• Asian Journal of Innovation and Policy
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• v.10 no.3
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• pp.274-293
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• 2021

Utilizing outside knowledge for innovation is an important task for companies in the competitive economy. Due to the rapid advance in the internet communication technology, the number and quality of innovation sourcing methods are increasing. We select co-creation, personalization and in-house R&D as the representative forms of innovation sourcing and suggest a game theory model that enables the comparative analysis between them. The decision and surplus outcome of the innovation mechanisms are compared under various settings of the input parameters of the model. The stakeholders voluntarily participate into all mechanisms when the product price is moderately high and the participation cost is low, while co-creation is the only feasible one when the product quality is niche. When the participation cost is relatively high, personalization outperforms co-creation.

• Journal of Multimedia Information System
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• v.8 no.4
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• pp.295-300
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• 2021

Recent advances in Internet-of-Things and wearable computing have established computationally sufficient infrastructure to remove the barriers of physical locations. The recent COVID-19 pandemic has accelerated the use of remote collaboration, work-from-home, teleconferencing, online education, digital twin, and metaverse enriched with various configurations of augmented reality, virtual reality, mixed reality, and extended reality. Beyond specialized niche wearable applications in the medical and entertainment domains, we aim to identify the underlying characteristics of smartglass-enabled killer applications for everyday use. In this paper, we analyze intermediary roles in remote collaboration consisting of authoritative supervisors, synergetic collaborators, and speculative explorers. We also propose technical components for smartglass-assisted interactive remote collaboration composed of personal tracking, teleconference, and interaction components. More specifically, the application tasks of each intermediary role and objectives of three functional components are defined and elaborated.