• Title/Summary/Keyword: Space availability

Search Result 282, Processing Time 0.025 seconds

ENHANCED ARCTIC PRIMARY PRODUCTIVITY FOLLOWING SEA ICE RAPID DECLINE

  • Comiso, Josefino C.
    • Proceedings of the KSRS Conference
    • /
    • v.2
    • /
    • pp.1019-1022
    • /
    • 2006
  • Satellite sea ice data from 1978 to the present reveal that the perennial ice (or ice that survives the summer) has been rapidly declining at almost 10% per decade. Warming due to increases in greenhouse gases in the atmosphere is now also being reflected in winter with drastic reductions in the maximum extent observed in 2005 and 2006. The retreat of the perennial ice also exposes more open water and has revealed an asymmetric distribution of chlorophyll a pigment concentration in the Arctic basin. Phytoplankton blooms are most dominant at high latitudes, partly on account of sea ice, but in the Arctic basin, it appears that pigment concentrations in the Eastern (Laptev Sea) Region are on the average three times higher than those in the Western (Beaufort Sea) Region. Such asymmetry suggests that despite favorable conditions provided by the melt of sea ice, there are other factors that affects the productivity of the region. The asymmetry is likely associated with much wider shelf areas in the East than in the West, with sea ice processes that inhibits the availability of nutrients near the surface in deep water regions, and river run-off that affects nutrient availability. The primary productivity in the pan-Arctic region have been estimated using the pigment concentrations and PAR derived from SeaWiFS data and the results show large seasonal as well as interannual variability during the 1998 to 2005 period. The data points towards increasing productivity for later years but with only 9 years of data it is too early to tell the overall effect of the sea ice retreat.

  • PDF

Implementation of Remote Physical Security Systems Using Smart Phone (스마트폰을 이용한 원격 물리적 보안 시스템의 구현)

  • Lee, Moon-Goo
    • Journal of the Korea Society of Computer and Information
    • /
    • v.16 no.2
    • /
    • pp.217-224
    • /
    • 2011
  • Existing wire based physical security system solutions show limitations in time and space. In order to solve these deficiencies, a remote physical security system has been implemented using smart phone based on mobile cloud computing technique. The security functions of mobile cloud computing technique include mobile device user authentication, confidentiality of communication, integrity of information, availability of system, and target system access control, authority management and secure hand off etc. Proposed system has been constructed as remote building management system using smart phone, and also has been efficient to reduce energy cost (5~30%), result of system average access and response time 7.082 second. This systems are evaluated to have high efficiency compared to performance.

A Dual-Population Memetic Algorithm for Minimizing Total Cost of Multi-Mode Resource-Constrained Project Scheduling

  • Chen, Zhi-Jie;Chyu, Chiuh-Cheng
    • Industrial Engineering and Management Systems
    • /
    • v.9 no.2
    • /
    • pp.70-79
    • /
    • 2010
  • Makespan and cost minimization are two important factors in project investment. This paper considers a multi-mode resource-constrained project scheduling problem with the objective of minimizing costs, subject to a deadline constraint. A number of studies have focused on minimizing makespan or resource availability cost with a specified deadline. This problem assumes a fixed cost for the availability of each renewable resource per period, and the project cost to be minimized is the sum of the variable cost associated with the execution mode of each activity. The presented memetic algorithm (MA) consists of three features: (1) a truncated branch and bound heuristic that serves as effective preprocessing in forming the initial population; (2) a strategy that maintains two populations, which respectively store deadline-feasible and infeasible solutions, enabling the MA to explore quality solutions in a broader resource-feasible space; (3) a repair-and-improvement local search scheme that refines each offspring and updates the two populations. The MA is tested via ProGen generated instances with problem sizes of 18, 20, and 30. The experimental results indicate that the MA performs exceptionally well in both effectiveness and efficiency using the optimal solutions or the current best solutions for the comparison standard.

Improving Availability of Embedded Systems Using Memory Virtualization

  • Son, Sunghoon
    • Journal of the Korea Society of Computer and Information
    • /
    • v.27 no.5
    • /
    • pp.11-19
    • /
    • 2022
  • In this paper, we propose a fault tolerant embedded system using memory redundancy on the full-virtualization based virtual machine monitor. The proposed virtual machine monitor first virtualizes main memory of embedded system utilizing efficient shadow page table scheme so that the embedded system runs as a virtual machine on the virtual machine monitor. The virtual machine monitor makes the backup of the embedded system run as another virtual machine by copying memory contents of the embedded system into memory space of backup system according to predefined schedules. When an error occurs in the target virtual machine, the corresponding standby virtual machine takes the role of target virtual machine and continues its operation. Performance evaluation studies show that such backups and switches of virtual machines are performed with minor performance degradation.

Resource-constrained Scheduling at Different Project Sizes

  • Lazari, Vasiliki;Chassiakos, Athanasios;Karatzas, Stylianos
    • International conference on construction engineering and project management
    • /
    • 2022.06a
    • /
    • pp.196-203
    • /
    • 2022
  • The resource constrained scheduling problem (RCSP) constitutes one of the most challenging problems in Project Management, as it combines multiple parameters, contradicting objectives (project completion within certain deadlines, resource allocation within resource availability margins and with reduced fluctuations), strict constraints (precedence constraints between activities), while its complexity grows with the increase in the number of activities being executed. Due to the large solution space size, this work investigates the application of Genetic Algorithms to approximate the optimal resource alolocation and obtain optimal trade-offs between different project goals. This analysis uses the cost of exceeding the daily resource availability, the cost from the day-by-day resource movement in and out of the site and the cost for using resources day-by-day, to form the objective cost function. The model is applied in different case studies: 1 project consisting of 10 activities, 4 repetitive projects consisting of 40 activities in total and 16 repetitive projects consisting of 160 activities in total, in order to evaluate the effectiveness of the algorithm in different-size solution spaces and under alternative optimization criteria by examining the quality of the solution and the required computational time. The case studies 2 & 3 have been developed by building upon the recurrence of the unit/sub-project (10 activities), meaning that the initial problem is multiplied four and sixteen times respectively. The evaluation results indicate that the proposed model can efficiently provide reliable solutions with respect to the individual goals assigned in every case study regardless of the project scale.

  • PDF

Two-Failure Gps Raim by Parity Space Approach (패러티 공간을 이용한 2개 GPS 파라미터 고장진단)

  • Yoo, Chang-Sun;Ahn, Iee-Ki;Lee,Sang-Jeong
    • Journal of the Korean Society for Aeronautical & Space Sciences
    • /
    • v.31 no.6
    • /
    • pp.52-60
    • /
    • 2003
  • In aviation navigation using GPS, requirements on availability and integrity must be absolutely satisfied. Current study on accomplishing this integrity includes RAIM(Receiver Autonomous Integrity Monitoring), monitoring integrity internaIly in GPS receiver itself. Parity space technique as one of RAIM techniques has shown the advantages in fault detection and isolation due to each use of its magnitude and direction under the assumption of one fault. ln case of multiple fault, as biases in errors interact decreasing the effect of multiple fault in parity space, the exact fault detection and identification(FDI) may be difficult to be conducted. This paper focuses on FDI study on two faults and explains why parity space techniques applied on single fault is not adequate to the application of multiple fault case and shows that extended parity space technique may improve the performance of RAIM on two faults.

Electromagnetic Field and the Poetry of Ezra Pound

  • Ryoo, Gi Taek
    • Journal of English Language & Literature
    • /
    • v.57 no.6
    • /
    • pp.939-958
    • /
    • 2011
  • Ezra Pound has an idea of poetry as a field of energy in which words interact with each other with kinetic energy. The energy field which Pound creates in his poem is analogous to the theory of electromagnetism developed by Michael Faraday and James Maxwell, who look upon the space around magnets, electric charges and currents not as empty but as filled with energy and activity. Pound argues that "words are charged with force like electricity," demonstrating that words charged with their own images or energies of positive or negative valence interact one another. This idea is similar to Faraday's concept of "line of force" which he used to represent the disposition of electric and magnetic forces in space. Pound's concept of "image" as an "intellectual and emotional complex in an instant" is remarkably consonant with the confluence of electric and magnetic fields that are coupled to each other as they travel through space in the form of electromagnetic waves. The instant profusion of conception and perception, much like that of electric and magnetic fields, enables Pound to move beyond the sequential and linear hierarchy in time and space. Particularly, Maxwell's stunning discovery that the electromagnetic waves propagate in space at 'the speed of light' has allowed Pound a relativistic sense of escape from the limitations of Newtonian absolute time and space. Pound's poetry transcends any geographical space and sequential time by rendering and juxtaposing images simultaneously. Pound was fully aware of light and electricity fundamental to what he called his world "the electric world." Pound's experiments in Imagism and Vorticism can be considered an attempt to rediscover a place for poetry in the modern world of science and technology. Almost all the appliances that we think of today as modern were laid down in the closing decades of the 19th century and the first decades of the 20th century, in response to the availability of electromagnetic energy. This paper explores how Pound responded to the age of modern technology and science, examining his conception of "image" through his many analogies and similes drawn from electromagnetism. Pound's imagist poetics and poetry come to embody, not only the characteristics of the electric age in the early twentieth century, but the principles of electromagnetism the electric age is based upon.

A Study on the Planning Standards of Parks and Open Space Planning (택지개발사업지구의 공원녹지계획 지표연구)

  • 김귀곤;성현찬;황기현
    • Journal of the Korean Institute of Landscape Architecture
    • /
    • v.22 no.1
    • /
    • pp.179-198
    • /
    • 1994
  • Urban parks and open spaces provide the community residents with the most easily accessible source for outdoor recreation, contributing also to the improvement of quality of natural environment in urban area. The demands of urban residents' for more and better green area are ever-increasing. However, the level of most urban open spaces which are easily accessible for residents are not satisfactory to meet the residents' demand in availability and in quality as well. Most existing urban open spaces are simply built of green areas only or have been developed in almost identical design with little consideration for individual uniqueness of the site. When developing neighbourhood parks in urban housing complexes, for example, little consideration is being given to topographical conditions, interrelation with the adjacent green area, or viability of the urban ecosystem. In many cases, urban park development projects are being done with serious negligence of natural properties of the site, by even destroying existing healthy woodlands. for instance. The objectives of this study are; -To survey on the domestic and the overseas cases of regulatory systems, development status and planning methods for urban open space. -To identify underlying issues of residental park developments in urban housing projects and establish appropriate improvement measures thereof, by studing and analyzing current-use data of developed urban parks and management status thereof. -To establish improved standards for urban open space planning, by integrating above surveys and studies, and recommendation for revision of related legislation is also presented to implement these standards.

  • PDF

A Study on the Art Management and Cultural Activities in China from the K-Wave Case

  • Jia Ning LI;Su SHUAI;Zhang FAN
    • Journal of Koreanology Reviews
    • /
    • v.2 no.1
    • /
    • pp.27-31
    • /
    • 2023
  • The purpose of this paper is to study the relationship between Art management and Cultural activities in China from the K-wave case. Research design, data, and methodology: This study used the method of the cases study survey, with the K-wave case in as the survey objects, 3 valid survey sample case were collected in this paper. Results: The two dimensions of art management and cultural activities differently influences from the K-wave, and the influence of availability on customer satisfaction is not significant. Conclusion: The results of this study will provide useful reference for the Art management and Cultural activities in China from the K-wave case. And improve the development of art management and cultural activities in China by improving the K-wave of service quality. Art management can shape urban commercial space in a beneficial way, create a good consumption atmosphere, and enhance the attractiveness and competitiveness of the city. The introduction of art elements into urban commercial space can create a strong cultural atmosphere, so that the city presents a smart look. Art management has a positive impact on K-Wave production and operation activities, which can promote the shaping of art commercial space, the promotion of urban cultural atmosphere.

Negotiations in Space and Time: Changing Gender Relations in Thai Tourist-oriented Encounters

  • King, Victor T.;Rotheray, J.
    • SUVANNABHUMI
    • /
    • v.11 no.2
    • /
    • pp.25-57
    • /
    • 2019
  • The paper addresses Erik Cohen's pioneering work on tourism in Thailand, specifically his publications on the relations between Thai women and foreign (farang) men in tourist-oriented encounters. Of sociological-anthropological interest is his conceptualization of these relations as "open-ended prostitution as a skilful game of luck" based on his study of a Bangkok soi (lane) in 1981-1984, and his exploration of Thai culture in terms of ambiguity and contradiction. On the basis of recent ethnographic research in the northern Thai tourist hub of Chiang Mai and wide-ranging observations on tourism development in Thailand, we examine continuity and change in these male-female engagements since Cohen's research, especially in the context of the increasing availability of such electronic agencies as social media, messaging, video chat, and internet dating. Whereas Cohen's concept of ambiguity and illusion has tended to disappear from physical spaces, it seems to have resurfaced in virtual space. The complexities of host-guest relations, and particularly the interactions both within the variegated category of "guests" themselves and then between their "hostesses" are explored in terms of sites of tourism-oriented encounters in both physical and virtual space so as to deconstruct these oppositional categories which have been formative in studies of tourism.

  • PDF