• Title/Summary/Keyword: 전자북

Search Result 326, Processing Time 0.028 seconds

Recognition of Seawater Intrusion Using Reference IP Technique (참조채널 유도분극탐사기술에 의한 해수침투대 인지)

  • Lee, Sang-Kyu;Hwang, Hak-Soo;Hwang, Se-Ho;Park, In-Hwa;Shin, Je-Hyun
    • Geophysics and Geophysical Exploration
    • /
    • v.5 no.1
    • /
    • pp.56-63
    • /
    • 2002
  • Tracing the history of study, problems of seawater intrusion are commonly investigated with electrical techniques because seawater saturated zone is indicative of the low resistivity anomaly. There we, however, silt and mud layers in the western and southern coastal areas of Korea, so we may make a mistake in case we determine seawater intrusion only with resistivity survey. Hence, reference IP survey was carried out in Kimje, Jeollabuk-Do and Youngkwang, Jeollanam-Do in order to decide whether or not the area is under the influence of seawater intrusion. With the use of a electric field cable to minimize EM coupling, we obtained more accurate results by appling reference If technique measuring simultaneously wavelet of current as well as potential. With the aid of reference IP technique, it is possible that we can exactly evaluate seawater intrusion by discriminating seawater saturated area (no IP effect) from very highly conductive layer composed of clay mineral (high IP effect).

Site Investigation for Pilot Scale $CO_2$ Sequestration by Magnetotelluric Surveys in Uiseong, Korea (이산화탄소 지중저장 Pilot 부지 선정을 위한 의성지역 MT 탐사)

  • Lee, Tae-Jong;Han, Nu-Ree;Ko, Kwang-Beom;Hwang, Se-Ho;Park, Kwon-Gyu;Kim, Hyung-Chan;Park, Yong-Chan
    • Geophysics and Geophysical Exploration
    • /
    • v.12 no.4
    • /
    • pp.299-308
    • /
    • 2009
  • A magentotelluric (MT) survey at the Uiseong area has been performed for the site investigation of pilot scale $CO_2$ sequestration. The purpose of the MT survey is to delineate deeply extended fracture systems that can act as a leakage path of injected $CO_2$ Plume. Since the target area is extremely noisy in electromagentic sense, low frequency data below 1 Hz cannot be used for inversion. Two- and three-dimensional interpretation of the MT data showed a very clear conductive anomaly, which has the direction of $N55\sim65^{\circ}W$ and is extended roughly down to 1.6 km. It have the same direction with the strike-slip faults, the Gaeum and Geumcheon Faults. On the contrary, the eastern part of the survey area shows relatively homogeneous to the depth of 2 km though some small fractures at shallow depths can be found. Test drilling and high-definition borehole surveys should be followed at the eastern part of the survey area and hydraulic fracturing is required for injection of $CO_2$, because mean porosity of the sedimetary rock in the area is only 1.47%.

Promotion Strategies for Daegu-Kyungbuk Mobile Cluster: Searching for Alternative Regional Innovation Governance (대구.경북 모바일 클러스터 육성전략: 지역혁신 거버넌스의 대안 모색)

  • Lee, Jeong-Hyop;Kim, Hyung-Joo
    • Journal of the Economic Geographical Society of Korea
    • /
    • v.12 no.4
    • /
    • pp.477-493
    • /
    • 2009
  • This research aims to examine Korean regional innovation governance, find structural problems, and explore alternative strategies of regional innovation governance. Especially the alternative governance was searched through the case study of Daegu-Kyungbuk mobile cluster, of which formulation Samsung is the anchor institution. Regional innovation governance in this research is defined as a policy system to link knowledge generation & diffusion subsystem and knowledge application & exploitation subsystem, and institutional conditions to steer the system. "Social Capital Assessment Tool (SOCAT)" of the World Bank was utilized for the appreciation of cluster governance. The regional innovation governance of Daegu-Kyungbuk mobile cluster is characterized as production networks dominated by one-to-one relationship between Samsung and hardware/software developers, decentralized R&D networks and policy networks with multiple hubs. Major policy agents have not developed networks with local companies, and rare are interactions between the policy agents. Local companies, especially software developers, responded they have had experiences to cooperate for local problem solving and shared their community goal, however, the degree of trust in major local project leaders is not high. Local hardware/software developers with core technologies need to be cooperative to develop similar technologies or products in Daegu-Kyungbuk mobile cluster. Regional administrative actors, such as the City of Daegu and Kyungsangbuk-do, and diverse innovation-related institutes should build cooperative environment where diverse project-based cooperation units are incessantly created, taken apart, and recreated.

  • PDF

A Research for Revising the Korean Archives Law with Interviews (공공기록물 관리에 관한 법령 개정을 위한 면담 연구)

  • Hyun, Moonsoo;Chung, Sanghee;Park, Min-Young;Hwang, Jin-Hyun;Lee, So-Yeon
    • The Korean Journal of Archival Studies
    • /
    • no.51
    • /
    • pp.279-306
    • /
    • 2017
  • This study aims to identify issues with regard to practicing the current Korean Archives Law and, by doing so, to boost a community-wide discussion for revising it. Five researchers collaboratively interviewed five groups of stake-holders. Each group was consisted of practitioners in central government agencies, provincial governments, and educational district offices, as well as instructors of archival education programs. To uncover diverse issues from various perspectives, the interview was initiated by a common question: "Do you have any idea in terms of revising the current law?" After all interview sessions were completed, the researchers discussed among themselves and established a framework for analysis. The study is expected to provide a starting point for the Korean archival community to reinvent the law so that the archival culture and practice in Korea could open a new era.

A Theoretical Review on the Untact Marketing of the COVID-19 Period Hospitality Industry Services (코로나 시대 환대산업 서비스의 언택트 마케팅에 관한 고찰)

  • Kang, Hee-Seog;Lee, Youn-Oak
    • Journal of Korea Entertainment Industry Association
    • /
    • v.14 no.7
    • /
    • pp.161-173
    • /
    • 2020
  • In-depth interview in the field of hospitality industry services was conducted in COVID- 19. Introduction of kiosks for non-face-to-face services using untact technology, reservation, pay systems, self-service, service improvement using room service should be carried out. It is also necessary to implement Instagram, Facebook, YouTube, P-blogs, online broadcasting and live commerce through the establishment of m-channel system through untact marketing sales channels in the hospitality industry now that the product composition to solve the pro -blem of untact marketing is drawing attention due to diversification of online sales channe -ls. Now, the recognition of important elements of service education and a establishment of differentiated system of untact marketing, expansion of untact sale channel, implementation of non-face-to-face counseling service and introduction of pre-booking, telecommuting were recognized as urgent parts. In particular, a service differentiation and importance of human services, which were recognized free of charge, have re-recognized as premium, and quality service aspect of the hospitality industry in untact and the direction to diversify marketing channels are presented.

Rock Mass Stability of the Buddha Statue on a Rock Cliff using Fracture Characteristics and Geological Face-Mapping (마애불 암반의 단열특성과 지질맵핑을 이용한 안정성 해석)

  • Ihm, Myeong Hyeok
    • The Journal of the Convergence on Culture Technology
    • /
    • v.9 no.1
    • /
    • pp.539-544
    • /
    • 2023
  • The subject of this study is the Maae Buddha statue in granodiorite of the Mesozoic Cretaceous period, which is concerned about stability as a standing stone cultural property located in ◯◯-dong, Gyeongsangbuk-do. For stability analysis, three-dimensional face mapping, geological properties of joints, three-dimensional scanning, ultrasonic velocity, polarization microscopy, electron microscopy analysis and XRD analysis were performed. In addition, the safety factor of the Maaebul was calculated by analyzing the damage status investigation, stereographic projection analysis, rock classification, and limit equilibrium analysis. The types and scales of damage and possible collapse by section depend on the degree of weathering of the rock and the orientation and characteristics of the joints, but wedge-failure and toppling-failure are expected to be small-scale. The safety factor of Maaebul in dry and wet conditions is less than 1.2, so stability is concerned. The types of damage were mainly observed, such as exfoliation, cracking, granular decomposition, and vegetation growth. The Maaebul rock is granodiorite, and the surface discoloration materials are K, Fe, and Mg. The 4 sets of joints are developed, J1 is tensile joint and the others are shear joint. The uniaxial compressive strength estimated by ultrasonic exploration is 514kgf/cm2, which corresponds to most soft rocks and some weathered rocks. Rock classification(RMR) is estimated to be grade 5, very poor rock mass. These technique along with the existing methods of safety diagnosis of cultural properties are expected to be a reasonable tool for objective interpretation and stability review of stone cultural properties.

Vegetation Structure and Main Characteristics in Habitat of Sarcodon impricatus (향버섯 발생지의 식생구조 및 주요 특성)

  • Mi-Ji Lee;Nam-In Koo;Kang-Hyeon Ka;Min-Su Kim
    • Korean Journal of Environment and Ecology
    • /
    • v.38 no.2
    • /
    • pp.156-168
    • /
    • 2024
  • This study was carried out to provide fundamental data for forest land and the environment by investigating the vegetation structure and soil properties of forest land where Sarcodon impricatus are present. The study area was divided into the Quercus mongolica community, dominated by Q. mongolica and the Quercus variabilis community, a mixed forest with Q. variabilis, Q. mongolica and Pinus densiflora. Also, Calamagrostis arundinacea in the former community and Disporum smilacinum and Carex siderosticta in the latter community showed significant levels as indicator species. Both communities showed a strong correlation between available phosphate and pH, sand, and clay, and the high organic matter content and slightly acidic pH of the soil are believed to be related to the development of S. impricatus. The species appearing at the lower layer continue to dominate because the species appearing at the upper layer have secured realized niches. The site was distributed in a relatively humid place in a north-east direction, and soil was developed with a thin litter layer and low rock exposure. In the selected S. impricatus growing areas, vegetation centered on highly adaptable species to disturbance or external interference was developed. Therefore, it is expected to be used as fundamental data to promote the occurrence of S. impricatus during artificial cultivation, as it is possible to identify the stand where S. impricatus occurs indirectly.

A Comparative Anatomical and Histological Study of the Olfactory Organ of Amphidromous and Land-locked Sweet Fish, Plecoglossus altivelis(Osmeriformes, Osmeridae), in Seomjingang River System, Korea (섬진강 수계에 출현하는 양측회유성과 육봉형 은어 Plecoglossus altivelis 후각기관의 해부 및 조직학적 구조 비교 연구)

  • Min Jeong Choi;Jong Young Park
    • Korean Journal of Ichthyology
    • /
    • v.36 no.3
    • /
    • pp.230-239
    • /
    • 2024
  • This study was carried out the anatomical and histological investigation of the olfactory organ on a land-locked and an amphidromous Plecoglossus altivelis in Deokam-ri, Shinpyeong-myeon, Imsil-gun, Jeollabuk-do and Daeduk-ri, Gojeon-myeon, Hadong-gun, Gyeongsangnam-do, August, 2021, Korea. The external morphology of the two types of P. altivelis was indistinguishable, featuring a pair of the elliptical anterior nostrils, the semicircular posterior nostrils, and the nasal flaps on the snout. The olfactory organ consisted of 20 to 22 olfactory lamellae forming a rosette structure in the nasal chamber. The secondary folds appeared on the lamellae. The histological results were also uniform. The sensory epithelium was a continuous type, consisting of olfactory receptor neurons, supporting cells, basal cells, cilia, and an unidentified cell. The non-sensory epithelium found only in the terminal part of lamellae, consist of stratified epithelial cells, basal cells, and mucous cells. For the olfactory organ between a land-lock type and an amphidromous type, no difference was observed in external and histological structure between amphidromous and land-locked type. However, it is considered that P. altivelis has higher olfactory sensitivity than other anadromous fish due to more number of olfactory lamellae and the presence of the secondary folds.

Characteristic Study of Small-sized and Planer Resonator for Mobile Device in Magnetic Wireless Power Transfer (소형 모바일 기기용 공진형 무선전력전송 시스템의 공진기 평면화 및 소형화에 따른 특성 연구)

  • Lee, Hoon-Hee;Jung, Chang-Won
    • Journal of the Institute of Electronics and Information Engineers
    • /
    • v.54 no.4
    • /
    • pp.16-21
    • /
    • 2017
  • In this paper, a Small-sized and planer resonator design of Magnetic Resonance - Wireless Power Transfer(MR-WPT) were proposed for practical applications of mobile devices, such as a laptop, a smart-phone and a tablet pc. The proposed MR-WPT system were based on four coil MR-WPT and designed as a transmitter part (Tx) and a receiver part (Rx) both are the same shape with the same loop and resonator. There are four different spiral coil type of resonators with variable of line length, width, gap and turns in $50mm{\times}50mm$ size. The both of top and bottom side of substrate(acrylic; ${\varepsilon}_r=2.56$, tan ${\delta}=0.008$) ere used to generate high inductance and capacitance in limited small volume. Loops were designed on the same plane of resonator to reduce their volume, and there are three different size. The proposed MR-WPT system were fabricated with two acrylic substrate plane of Tx and Rx each, the Rx and Tx loops and resonators were fabricated of copper sheets. There are 12 combinations of 3 loops and 4 resonators, each combination were measured to calculate transfer efficiency and resonance frequency in transfer distance from 1cm to 5cm. The measured results, the highest transfer efficiency was about 70%, and average transfer efficiency was 40%, on the resonance frequency was about 6.78 MHz, which is standard band by A4WP. We proposed small-sized and planer resonator of MR-WPT and showed possibility of mobile applications for small devices.

Finding Influential Users in the SNS Using Interaction Concept : Focusing on the Blogosphere with Continuous Referencing Relationships (상호작용성에 의한 SNS 영향유저 선정에 관한 연구 : 연속적인 참조관계가 있는 블로고스피어를 중심으로)

  • Park, Hyunjung;Rho, Sangkyu
    • The Journal of Society for e-Business Studies
    • /
    • v.17 no.4
    • /
    • pp.69-93
    • /
    • 2012
  • Various influence-related relationships in Social Network Services (SNS) among users, posts, and user-and-post, can be expressed using links. The current research evaluates the influence of specific users or posts by analyzing the link structure of relevant social network graphs to identify influential users. We applied the concept of mutual interactions proposed for ranking semantic web resources, rather than the voting notion of Page Rank or HITS, to blogosphere, one of the early SNS. Through many experiments with network models, where the performance and validity of each alternative approach can be analyzed, we showed the applicability and strengths of our approach. The weight tuning processes for the links of these network models enabled us to control the experiment errors form the link weight differences and compare the implementation easiness of alternatives. An additional example of how to enter the content scores of commercial or spam posts into the graph-based method is suggested on a small network model as well. This research, as a starting point of the study on identifying influential users in SNS, is distinctive from the previous researches in the following points. First, various influence-related properties that are deemed important but are disregarded, such as scraping, commenting, subscribing to RSS feeds, and trusting friends, can be considered simultaneously. Second, the framework reflects the general phenomenon where objects interacting with more influential objects increase their influence. Third, regarding the extent to which a bloggers causes other bloggers to act after him or her as the most important factor of influence, we treated sequential referencing relationships with a viewpoint from that of PageRank or HITS (Hypertext Induced Topic Selection).