• Title/Summary/Keyword: large-scale structure

Search Result 1,306, Processing Time 0.025 seconds

The Impact Structure on Co-Creation, Shared Value and Customer Satisfaction of Customer Acceptance for Servicescape: Focusing on Theme Park Service (서비스스케이프에 대한 고객수용이 공동창조 및 공유가치와 고객만족에 미치는 영향 구조: 테마파크서비스를 중심으로)

  • Ahn, Yeon S.
    • Journal of Service Research and Studies
    • /
    • v.10 no.1
    • /
    • pp.97-107
    • /
    • 2020
  • The purpose of this study is to demonstrate the effect of customer acceptance of servicescape on customer satisfaction focusing in theme park service. In particular, the degree of usefulness and ease of use perceived for servicescape will ultimately have the impact on customer satisfaction through the process of service co-creation and shared values creation. In order to demonstrate this structural influence relationship, a survey of 247 undergraduate and graduate students taking service management course was conducted. The customer's acceptance of the servicescape affects the co-creation activities of the service. It creates value and contributes to the improvement of satisfaction. Looking at the results of this study in detail, it is necessary to take into consideration the usefulness of the theme park employees' clothes and symbols, etc. in servicescape, and the convenience of the facility itself is important. This servicescape reveals that customers should be comfortable with the use of real-time information on the site and that customer satisfaction can be improved by creating new shared value. This study has been limited to the theme park service which has a large-scale service field and the distribution status of many customers in real time, so it is limited to apply to the other services with detail reinterpreting.

Solar Detoxification of Trichloroethylene in Waste Water with Slurry Batchtype Photoreactor (Slurry batch형 광화학 반응기를 이용한 폐수 내의 Trichlroethylene의 분해)

  • Lee, Tai-K.;Kim, Dong-H.;Cho, Sug-H.;Auh, Chung-Moo
    • Solar Energy
    • /
    • v.12 no.3
    • /
    • pp.10-20
    • /
    • 1992
  • In this experiment, photochemical reaction has been applied to destroy TCE in water phase. The main target of this work is to investigate the technical feasibility of large scale of solar detoxification reactor for water treatment. The results have revealed that solar detoxification utilizing photon energy from the sun is the most attractive process to decompose organic toxins in water phase at room temperature. The detailed results from this work are as follows; (1) The highest conversion ratio of TCE was obtained by using $TiO_2$, annatase as a photocatalyst among $TiO_2$ anatase, $TiO_2$ rutile and $V_2O_5$ under the same experimental condition. The anatase crystal structure was confirmed with XRD analysis, and its surface area was 7.748 $m^2/g$ from the BET-$N_2$ measurement (2) 0.1 wt% of $TiO_2$ anatase has been adopted as optimal quantity for batch slurry reactor at this experimental conditions. (3) The effect of hydrogen peroxide on the conversion of TCE was investigated. Its optimal quantity was 0.06 vol. % under this experimental conditions. (4) The effect of oxygen on the conversion of TCE also was studied by controlling the head space in photoreactor. Results indicated that sufficient amount of oxygen should be supplied to accomplish the highest conversion rate of TCE in water phase.

  • PDF

Improving of Planning System for Sustainable Urban Development -Focus on Introducing Environmental and Ecological Planning- (지속가능한 도시개발사업 추진을 위한 계획시스템 개선방안 -환경생태계획 도입을 중심으로 -)

  • Choi, Hee-Sun;Kwan, Young-Hwan
    • Journal of Environmental Policy
    • /
    • v.8 no.3
    • /
    • pp.27-51
    • /
    • 2009
  • This study looked for ways to carry out development projects in a sustainable manner by generating improvement plans, and focused on reviewing the status and problems associated with the environmental and ecological planning that is currently applied to new town and large-scale development projects. Improved methods were suggested based on differences between urban development and housing development projects. Based on principles set for the introduction of environmental and ecological planning, the size of the projects subject to environmental and ecological planning was set. With regard to the procedural improvements for environmental and ecological planning, nine problems were singled out from the development planning phases. Solutions were suggested by separating the problems into the site and district designation phase, development planning phase, implementation planning phase, and post-management phase based on a literature review and the opinion of experts. In consideration of improvements to the planning system, the scope of environmental and ecological planning was set after looking at information related to environmental and ecological planning, literature review, expert interviews, and the relevance of related plans. The scope of the environmental and ecological planning was divided into the overview of planning, environmental and ecological conception, conception of spatial structure and framework, and urban environment regeneration and impact reduction plans. By synthesizing the above-described results, the functions of environmental and ecological planning, development planning, and environmental assessment and their inter-relations were defined. The defined inter-relations seem likely to be developed into a form that would enable sustainable land development.

  • PDF

HALO SPIN PARAMETER IN COSMOLOGICAL SIMULATIONS

  • Ahn, Jieun;Kim, Juhan;Shin, Jihye;Kim, Sungsoo S.;Choi, Yun-Young
    • Journal of The Korean Astronomical Society
    • /
    • v.47 no.2
    • /
    • pp.77-86
    • /
    • 2014
  • Using a cosmological ${\Lambda}CDM$ simulation, we analyze the differences between the widely-used spin parameters suggested by Peebles and Bullock. The dimensionless spin parameter ${\lambda}$ proposed by Peebles is theoretically well-justified but includes an annoying term, the potential energy, which cannot be directly obtained from observations and is computationally expensive to calculate in numerical simulations. The Bullock's spin parameter ${\lambda}^{\prime}$ avoids this problem assuming the isothermal density profile of a virialized halo in the Newtonian potential model. However, we find that there exists a substantial discrepancy between ${\lambda}$ and ${\lambda}^{\prime}$ depending on the adopted potential model (Newtonian or Plummer) to calculate the halo total energy and that their redshift evolutions differ to each other significantly. Therefore, we introduce a new spin parameter, ${\lambda}^{\prime\prime}$, which is simply designed to roughly recover the value of ${\lambda}$ but to use the same halo quantities as used in ${\lambda}^{\prime}$. If the Plummer potential is adopted, the ${\lambda}^{\prime\prime}$ is related to the Bullock's definition as ${\lambda}^{\prime\prime}=0.80{\times}(1+z)^{-1/12}{\lambda}^{\prime}$. Hence, the new spin parameter ${\lambda}^{\prime\prime}$ distribution becomes consistent with a log-normal distribution frequently seen for the ${\lambda}^{\prime}$ while its mean value is much closer to that of ${\lambda}$. On the other hand, in case of the Newtonian potential model, we obtain the relation of ${\lambda}^{\prime\prime}=(1+z)^{-1/8}{\lambda}^{\prime}$; there is no significant difference at z = 0 as found by others but ${\lambda}^{\prime}$ becomes more overestimated than ${\lambda}$ or ${\lambda}^{\prime\prime}$ at higher redshifts. We also investigate the dependence of halo spin parameters on halo mass and redshift. We clearly show that although the ${\lambda}^{\prime}$ for small-mass halos with $M_h$ < $2{\times}10^{12}M_{\odot}$ seems redshift independent after z = 1, all the spin parameters explored, on the whole, show a stronger correlation with the increasing halo mass at higher redshifts.

Vegetation Composition and Structure of Sogwang-ri Forest Genetic Resources Reserve in Uljin-gun, Korea (울진 소광리 산림유전자원보호구역 산림식생의 조성 및 구조)

  • Kim, Hak-Yun;Cho, Hyun-Je
    • Korean Journal of Environment and Ecology
    • /
    • v.31 no.2
    • /
    • pp.188-201
    • /
    • 2017
  • Based on a total of 272 vegetation data collected by the ZM school phytosociological study method, the composition and structural characteristics of the forest vegetation in the Sogwang-ri forest genetic resource reservoir located in Uljin-gun, Gyeongsangbuk-do were compared using the table comparison method and the TWINSPAN method, And their ecological characteristics were analyzed. The types of forest vegetation were classified into 7 types, and it was divided into two major groups, 'Slope and Ridge type', which characterized by Quercus mongolica, Pinus densiflora for. erecta, Lespedeza bicolor etc. and 'valley and concave slope', which characterized by Cornus controversa, Fraxinus mandshurica, Morus bombycis, Hydrangea serrata for. acuminata etc. The hierarchy of the vegetation unit was 2 community groups, 4 communities, and 6 subcommunities. The structural characteristics such as the total percent cover, species importance value, species diversity of the constituent species per unit area($/100m^2$) of each type of forest vegetation were also identified. In order to understand the spatial distribution of forest vegetation, 1/5,000 large-scale physiognomic vegetation map was created by the uppermost dominant species. The composition and structural characteristics of Geumgang pine(P. densiflora for. erecta) forest, which is a core community of protected area by natural and anthropogenic influences, appear as a subtype of Quercus mongolica forest, which is a potential natural vegetation, Appropriate maintenance measures seemed urgently needed.

Forest Environment Degradation and Rehabilitation of Copper Mine Area in Ashio, Japan (일본 아시오(足尾) 銅鑛山地域의 삼림황폐와 삼림환경 복구사업에 관한 분석)

    • Korean Journal of Environment and Ecology
    • /
    • v.15 no.3
    • /
    • pp.276-285
    • /
    • 2001
  • This report surveyed degradation of forest environment and rehabilitation in Ashio of Japan. Since 1880, a large scale forestry in this area has been destroyed by sooty smoke, and the local government invested heavily to rehabilitate the damaged forestry and denuded mountains. These degradations are due to complex operations, such as sulfurous acid gas from copper refinery, forest fires, steep slope and disadvantageous climate. The rehabilitation works on degraded forestry(2,399ha) were undertaken by tree planting fur three years from 1897. However, forest degradation and disasters were continued, and the total damaged areas were about 2,400~3,000ha in 1956. A Manual labor method, a Helicopter method and also Combination of manual labor and helicopter method had been adopted to rehabilitation works from 1945 to 1996, while 828.19ha of the degraded mountains was rehabilitated. Total investment for those projects was 80 billion yen. A debris control dam, a soil arresting structure, a vegetation-block, a vegetation sack measures and tree planting have implemented significantly fur the method of rehabilitation. An objective of manual labor works is a complete rehabilitation on each place through 3 stage working. The revived green areas accounted fur 49% of the total, and the entire afforest areas are less than 10%. In coming 25 years, an amount of 21.3 billion yen will be invested to rehabilitate 564ha of degraded mountain lands. However, it is impossible to estimate that how long it will take until the whole degraded mountain lands are completely rehabilitated. Rehabilitation works in Ashio may be applicable to environmental restoration and revegetation in the abandoned coal-mine lands of Korea.

  • PDF

FORMATION AND EVOLUTION OF SELF-INTERACTING DARK MATTER HALOS

  • AHN KYUNGJIN;SHAPIRO PAUL R.
    • Journal of The Korean Astronomical Society
    • /
    • v.36 no.3
    • /
    • pp.89-95
    • /
    • 2003
  • Observations of dark matter dominated dwarf and low surface brightness disk galaxies favor density profiles with a flat-density core, while cold dark matter (CDM) N-body simulations form halos with central cusps, instead. This apparent discrepancy has motivated a re-examination of the microscopic nature of the dark matter in order to explain the observed halo profiles, including the suggestion that CDM has a non-gravitational self-interaction. We study the formation and evolution of self-interacting dark matter (SIDM) halos. We find analytical, fully cosmological similarity solutions for their dynamics, which take proper account of the collisional interaction of SIDM particles, based on a fluid approximation derived from the Boltzmann equation. The SIDM particles scatter each other elastically, which results in an effective thermal conductivity that heats the halo core and flattens its density profile. These similarity solutions are relevant to galactic and cluster halo formation in the CDM model. We assume that the local density maximum which serves as the progenitor of the halo has an initial mass profile ${\delta}M / M {\propto} M^{-{\epsilon}$, as in the familiar secondary infall model. If $\epsilon$ = 1/6, SIDM halos will evolve self-similarly, with a cold, supersonic infall which is terminated by a strong accretion shock. Different solutions arise for different values of the dimensionless collisionality parameter, $Q {\equiv}{\sigma}p_br_s$, where $\sigma$ is the SIDM particle scattering cross section per unit mass, $p_b$ is the cosmic mean density, and $r_s$ is the shock radius. For all these solutions, a flat-density, isothermal core is present which grows in size as a fixed fraction of $r_s$. We find two different regimes for these solutions: 1) for $Q < Q_{th}({\simeq} 7.35{\times} 10^{-4}$), the core density decreases and core size increases as Q increases; 2) for $Q > Q_{th}$, the core density increases and core size decreases as Q increases. Our similarity solutions are in good agreement with previous results of N-body simulation of SIDM halos, which correspond to the low-Q regime, for which SIDM halo profiles match the observed galactic rotation curves if $Q {\~} [8.4 {\times}10^{-4} - 4.9 {\times} 10^{-2}]Q_{th}$, or ${\sigma}{\~} [0.56 - 5.6] cm^2g{-1}$. These similarity solutions also show that, as $Q {\to}{\infty}$, the central density acquires a singular profile, in agreement with some earlier simulation results which approximated the effects of SIDM collisionality by considering an ordinary fluid without conductivity, i.e. the limit of mean free path ${\lambda}_{mfp}{\to} 0$. The intermediate regime where $Q {\~} [18.6 - 231]Q_{th}$ or ${\sigma}{\~} [1.2{\times}10^4 - 2.7{\times}10^4] cm^2g{-1}$, for which we find flat-density cores comparable to those of the low-Q solutions preferred to make SIDM halos match halo observations, has not previously been identified. Further study of this regime is warranted.

A Study of a Rate Limit Method for QoS Guarantees in Ethernet (이더넷에서의 QoS 보장을 위한 대역제한에 관한 연구)

  • Chung, Won-Young;Park, Jong-Su;Kim, Pan-Ki;Lee, Jung-Hee;Lee, Yong-Surk
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.32 no.2B
    • /
    • pp.100-107
    • /
    • 2007
  • Recently, a study of BcN(Broadband convergence Network) is progressing continuously, and it is important to improve the quality of the service according to subscribers because a scale of network is about to be larger. It is more important to manage QoS(Quality of Service) of all subscribers in layer 2 than layer 3 network since managing it in layer 3 network cost both additional processes and large hardware. Moreover, QoS based on Best-Effort service has been developed because tots of subscribers should use limited resource in BcN. However, they want to be supplied with different service even though they pay more charge. Therefore, it is essential to assign the different bandwidth to subscribers depending on their level of charge. The method of current Rate Limiter limits the bandwidth of each port that does not offer fair service to subscribers. The Rate Limiter proposed in this paper limits bandwidth according to each subscriber. Therefore, subscribers can get fair service regardless of switch structure. This new Rate Limiter controls the bandwidth of subscribers according to the information of learning subscriber and manages maximum performance of Ethernet switch and QoS.

Recovery Process of Forest Edge Formed by Clear-cutting Harvest in Korean Red Pine (Pinus densiflora) Forest in Gangwondo, South Korea (강원도 남부 지역에서 소나무림 벌채 후 형성된 숲 가장자리의 회복 과정)

  • Kim, Jun-Soo;Cho, Yong-Chan;Bae, Kwan-Ho
    • Journal of Korean Society of Forest Science
    • /
    • v.106 no.1
    • /
    • pp.1-9
    • /
    • 2017
  • Forest harvest as large scale artificial disturbance makes edge environment in both clear-cutted and forested habitat. To clarify the development and recovery process of forest edge after disturbances is essential to understand vegetation responses and landscape level consequences such as edge-distance. In Korea, after clear-cutting, edge-related changes of environment and vegetation was not clarified yet. In Korean red pine (Pinus densiflora) forest, by applying space-for-time approach (sites with undisturbed and 1, 3, 10, 16 yr after cutting), the edge-related change of plant abundance and abiotic factors were determined for 20 line-transect (60 m) and 340 ($1m{\times}5m$) quadrats, and clarified depth and duration of the disturbance. Immediately after edge formation, within 15m form the edge, biotic and abiotic factors such as cover, richness, canopy openness, temperature and moisture content exhibited larger changes compared to forest interior. Plant abundance and abiotic variables were stabilized at the level of forest inside within 16 yr and 10 yr after edge creation, respectively. Woody (tree and shrub) species generally was showed larger increment with proximity to edge than did herb or graminoid species. In addition, negative interactions between woody and herbaceous species were detected during the period of forest edge closure. Our results suggested that depth of forest edge formed by clear-cutting of Korean red pine forest was at least from 15 m to 20 m and edge effect were likely sustained more than 16 years. As the first empirical study on edge-distance between two contrast habitats of clear-cutted and adjacent forest in South Korea, the analytical reality on landscape structure and habitat patches can be improved.

Effects of the water level reduction and the flow distribution according to change of the side weir location in detention reservoir (홍수조절지 횡월류위어의 위치 변화에 따른 수위 저감 및 유량 분담 효과)

  • Seong, Hoje;Park, Inhwan;Rhee, Dong Sop
    • Journal of Korea Water Resources Association
    • /
    • v.51 no.7
    • /
    • pp.555-564
    • /
    • 2018
  • The detention reservoir is a hydraulic structure that constructs a levee on the inland of river and sets up side weir in a section of the levee, and this facility stores a part of the flood volume in case of a flood event over a certain scale. In order to optimize the operation of detention reservoir, it is necessary to review the linkage with existing facilities in the river. In this study, the effect of water level reduction and the flow distribution was analyzed according to the location of the side weir in the detention reservoir considering the run-of-the-river gate. Two radial gates were installed in the experimental channel, and the water level in channel and the overflow of weir were measured by moving the location of the side weir upstream from the gate. As a results of experiment, it was confirmed that the water level reduction is more remarkable as the location of the side weir was closer to the gate, and the effect of flow distribution is not greatly changed. When two or more side weirs were operated, it is confirmed that the sufficient storage space was secured and the water level reduction effect with the location of the side weir is not large. In addition, the water level reduction rate according to the location of the side weir was estimated by empirical formula and it is provided as basic data that can be used in the planning of the detention reservoir.