• Title/Summary/Keyword: Time Delays

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Evaluation of Management Performance for Heritage Buildings Case Study: Greco-Roman Museum - Alexandria, Egypt

  • Adel El-Menchawy;Wael Kamel;Amal Mamdouh;Mirna Eskander
    • Architectural research
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    • v.25 no.3
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    • pp.41-51
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    • 2023
  • Building restoration is a complex process with a high level of uncertainty. Restoration professionals can significantly benefit from the well-established discipline of project management to achieve their targets; however, available evidence shows that the use of the project management body of knowledge in restoration projects is far from the desired level. Several historical organisations have since been established with the goal of preserving and governing cultural identity, and numerous studies have supported the need of preserving architectural heritage. Many owners, investors, academics, and developers believe that it would be considerably more expensive to renovate and restore an old building than to create a new one. Although the project management process is generally recognised, the concept of project management for architectural heritage projects differs due to the uniqueness of each project. It differs from many construction projects in terms of the need for research-based practices to define scope, planning, scheduling, supervision,decision-making,and also performance. The Greco-Roman Museum in Alexandria's planning, design, and building phases are being studied with the aim of identifying and analysing the variables that contribute to project delays. Three project management pillars were established as a result of gathering this data from the project's stakeholders: the first pillar addresses time management for the existing phase and how it will be incorporated into the new extension phase; the second pillar addresses performance in relation to project management issues in the delivery of the best quality of a construction project; and the third pillar addresses the scope of the new extension because it will significantly impact the other two pillars. This paper argues that a contemporary perspective which utilizes project management tools and techniques can contribute to the conservation of architectural heritage in line with the conservation principles.

A Study on the Estimation of Ship Location Information in the Intelligent Maritime Traffic Information System (지능형 해상교통정보시스템의 선박 위치 정보 추정 연구)

  • Deuk-Jae Cho
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2022.06a
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    • pp.313-314
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    • 2022
  • The intelligent maritime traffic information service provides a service to prevent collisions and stranding of ships based on the location information of ships periodically collected from ship equipment such as LTE-Maritime transceivers and AIS installed on ships. provided in real time. However, the above service may reduce the reliability of ship location information because GPS location information for measuring the ship's location may be cut off during transmission through LTE-Maritime or AIS networks, or phenomena such as location jumps and delays may occur. This study aims to estimate reliable position information to some extent even in an abnormal section through ship position prediction based on the existing received position information using the Kalman filter, which is an optimal estimation filter based on probability.

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Thermo-mechanical compression tests on steel-reinforced concrete-filled steel tubular stub columns with high performance materials

  • David Medall;Carmen Ibanez;Ana Espinos;Manuel L. Romero
    • Steel and Composite Structures
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    • v.49 no.5
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    • pp.533-546
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    • 2023
  • Cost-effective solutions provided by composite construction are gaining popularity which, in turn, promotes the appearance on the market of new types of composite sections that allow not only to take advantage of the synergy of steel and concrete working together at room temperature, but also to improve their behaviour at high temperatures. When combined with high performance materials, significant load-bearing capacities can be achieved even with reduced cross-sectional dimensions. Steel-reinforced concrete-filled steel tubular (SR-CFST) columns are one of these innovative composite sections, where an open steel profile is embedded into a CFST section. Besides the renowned benefits of these typologies at room temperature, the fire protection offered by the surrounding concrete to the inner steel profile, gives them an enhanced fire performance which delays its loss of mechanical capacity in a fire scenario. The experimental evidence on the fire behaviour of SR-CFST columns is still scarce, particularly when combined with high performance materials. However, it is being much needed for the development of specific design provisions that consider the use of the inner steel profile in CFST columns. In this work, a new experimental program on the thermo-mechanical behaviour of SR-CFST columns is presented to extend the available experimental database. Ten SR-CFST stub columns, with circular and square geometries, combining high strength steel and concrete were tested. It was seen that the circular specimens reached higher failure times than the square columns, with the failure time increasing both when high strength steel was used at the embedded steel profile and high strength concrete was used as infill. Finally, different proposals for the reduction coefficients of high performance materials were assessed in the prediction of the cross-sectional fire resistance of the SR-CFST columns.

Analysis on Performance Assessment Framework of Construction Phase for Road Construction Projects (도로건설사업 시공단계 성과평가 프레임워크 연구)

  • Mun, Junbu;Lee, Kangwook;Yun, Sungmin
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.43 no.6
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    • pp.801-809
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    • 2023
  • Road construction projects have a long duration so cost overruns and schedule delays are occurred. However, performance assessment system that can manage and prepare for this in advance is insufficient. In addition, road construction are affected by many factors during under construction. Therefore it is necessary to conduct performance assessment considering the characteristics of roads and prepare for similar projects in the future. The purpose of this study is to provide a framework to evaluate construction phase performance and present a performance management plan using road construction information. Also, This study conducted time adjustment between the start and the finish of the project and developed performance metrics based on absolute and relative indicator. This study analyzed the cost, schedule, and changes of the road project construction process, showing the possibility of advancement of performance assessment and how to use it when planning new road construction projects.

Managerial Overconfidence and Stock Price Delay (경영자과신성향이 주가지체에 미치는 영향)

  • Myung-Gun Lee;Young-Tae Yoo
    • Asia-Pacific Journal of Business
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    • v.14 no.3
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    • pp.187-204
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    • 2023
  • Purpose - This study deals with the manager's overconfidence and stock price delay, and verified whether the stock price delay phenomenon changes as the overconfidence increases. Design/methodology/approach - Manager overconfidence means that managers have over confidence in their positions or abilities, and was measured according to Schrand and Zechman (2012). Stock price delay is a phenomenon in which information of company is not immediately reflected in the stock price, but is reflected over time, and was measured by the method suggested in a study by Hou and Moskowitz (2005). The analysis subjects used in this study are companies listed on the KOSPI market between 2011 and 2019, and the final sample is 5,509 company-years. Findings - As a result of the verification, it was shown that the stock price delay decreased as the manager's overconfidence increased, and this effect was amplified as the foreign shareholder's share ratio increased and the number of follow-up financial analysts increased. This means that as the manager's overconfidence increases, he actively provides high-quality information to the capital market. In addition, as a result of subdividing the manager's overconfidence into the investment and capital raising aspects, the capital raising aspect has a significant effect on reducing stock delays. This can be interpreted as the fact that managers with overconfident tendencies have a greater incentive to satisfy investors' information needs. Research implications or Originality - In previous studies, the characteristics of managers with strong overconfidence have both positive and negative aspects. The results of this study are significant in that they clearly demonstrated the positive aspect through the market variable of stock price delay, and it is expected to help capital market stakeholders understand the characteristics of managers with a strong propensity for overconfidence.

Evidence-based management of isolated dentoalveolar fractures: a systematic review

  • Samriddhi Burman;Babu Lal;Ragavi Alagarsamy;Jitendra Kumar;Ankush Ankush;Anshul J. Rai;Md Yunus
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.50 no.3
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    • pp.123-133
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    • 2024
  • Dentoalveolar (DA) trauma, which can involve tooth, alveolar bone, and surrounding soft tissues, is a significant dentofacial emergency. In emergency settings, physicians might lack comprehensive knowledge of timely procedures, causing delays for specialist referral. This systematic review assesses the literature on isolated DA fractures, emphasizing intervention timing and splinting techniques and duration in both children and adults. This systematic review adhered to PRISMA guidelines and involved a thorough search across PubMed, Google Scholar, Semantic Scholar, and the Cochrane Library from January 1980 to December 2022. Inclusion and exclusion criteria guided study selection, with data extraction and analysis centered on demographics, etiology, injury site, diagnostics, treatment timelines, and outcomes in pediatric (2-12 years) and adult (>12 years) populations. This review analyzed 26 studies, categorized by age into pediatrics (2-12 years) and adults (>12 years). Falls were a common etiology, primarily affecting the anterior maxilla. Immediate management involved replantation, repositioning, and splinting within 24 hours (pediatric) or 48 hours (adult). Composite resin-bonded splints were common. Endodontic treatment was done within a timeframe of 3 days to 12 weeks for children and 2-12 weeks for adults. Tailored management based on patient age, tooth development stage, time elapsed, and resource availability is essential.

Issues and Implications of Disputes related to Network Usage Fees (망이용대가 관련 분쟁의 쟁점과 함의)

  • Chang-Hee Rho;Joonho Do
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.24 no.3
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    • pp.123-131
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    • 2024
  • The dispute between SK and Netflix, which has been going on for more than three years, ended in the direction of dropping the lawsuit and establishing a cooperative relationship between the two companies. However, as Internet traffic usage is likely to increase further in the future due to digital transformation and activation of generated AI, conflicts between domestic mobile carriers and global CP operators over network usage fees can arise at any time. In this study, the issues of the dispute related to network usage fees that occurred between SK and Netflix were examined, and different implications were drawn for each issue. The cost and scope of network usage considerations are an issue that must be determined entirely by negotiations between operators. However, if a dispute occurs between operators, user damage such as speed delays may occur, so it is necessary to prepare a policy alternative. As the domestic media industry has grown cooperatively with global CPs, it is considered important to form a reciprocal relationship between domestic mobile telecommunication operators and global CP operators regarding network usage fees in the future.

A Study on Predictive Traffic Control Algorithms for ABR Services (ABR 서비스를 위한 트래픽 예측 제어 알고리즘 연구)

  • 오창윤;장봉석
    • Journal of Internet Computing and Services
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    • v.1 no.2
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    • pp.29-37
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    • 2000
  • Asynchronous transfer mode is flexible to support multimedia communication services using asynchronous time-sharing and statistical multimedia techniques to the existing data communication area, ATM ABR service controls network traffic using feedback information on the network congestion situation in order to guarantee the demanded service qualities and the available cell rates, In this paper we apply the control method using queue length prediction to the formation of feedback information for more efficient ABR traffic control. If backward node receive the longer delayed feedback information on the impending congestion, the switch can be already congested from the uncontrolled arriving traffic and the fluctuation of queue length can be inefficiently high in the continuing time intervals, The feedback control method proposed in this paper predicts the queue length in the switch using the slope of queue length prediction function and queue length changes in time-series, The predicted congestion information is backward to the node, NLMS and neural network are used as the predictive control functions, and they are compared from performance on the queue length prediction. Simulation results show the efficiency of the proposed method compared to the feedback control method without the prediction, Therefore, we conclude that the efficient congestion and stability of the queue length controls are possible using the prediction scheme that can resolve the problems caused from the longer delays of the feedback information.

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Comparison of Network-RTK Surveying Methods at Unified Control Stations in Incheon Area (인천지역 통합기준점에서 Network-RTK 측량기법의 비교)

  • Lee, Yong Chang
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.32 no.5
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    • pp.469-479
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    • 2014
  • N-RTK(Network based RTK) methods are able to improve the accuracy of GNSS positioning results through modelling of the distance-dependent error sources(i.e. primarily the ionospheric and tropospheric delays and orbit errors). In this study, the comparison of the TTFF(Time-To-Fix-First ambiguity), accuracy and discrepancies in horizontal/vertical components of N-RTK methods(VRS and FKP) with the static GNSS at 20 Unified Control Stations covering Incheon metropolitan city area during solar storms(Solar cycle 24 period) were performed. The results showed that the best method, compared with the statics GNSS survey, is the VRS, followed by the FKP, but vertical components of both VRS and FKP were approximately two times bigger than horizontal components. The reason for this is considered as the ionospheric scintillation because of irregularities in electron density, and the tropospheric scintillation because of fluctuations on the refractive index take the place. When the TTFF at each station for each technique used, VRS gave shorter initialization time than FKP. The possible reasons for this result might be the inherent differences in principles, errors in characteristics of different correction networks, interpolating errors of FKP parameters according to the non-linear variation of the dispersive and non-dispersive errors at rover when considering both domestic mobile communication infra and the standardized high-compact data format for N-RTK. Also, those test results revealed degradation of positing accuracy, long initialization time, and sudden re-initialization, but more failures to resolve ambiguity during space weather events caused by Sunspot activity and solar flares.

Delayed Transfer of Major Trauma Patients Under the Current Emergency Medical System in Korea (현재의 국내 응급의료체계에서 중증외상환자의 이송 지연)

  • Jung, Kyoung-Won;Jang, Jeong-Moon;Kim, Ji-Young;Baek, Suk-Ja;Song, Seo-Young;Gang, Chan-Suk;Lee, Kug-Jong
    • Journal of Trauma and Injury
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    • v.24 no.1
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    • pp.25-30
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    • 2011
  • Purpose: Major trauma patients should be transferred to a definitive care facility as early as possible because prompt management will prevent death. This study was designed to discover the obstacles leading to delayed transfers under the current emergency medical system in Korea and whether there are any negative outcomes associated with conducting procedures at primary care hospitals prior to transferring patients to higher levels of care. Methods: The medical records of major trauma patients with an Injury Severity Score above 15 within the past year were reviewed. Patients were divided three groups as follows: (A) came directly to our emergency center, (B) were transferred without CT or MRI scan at the primary care hospital and (C) transferred with CT or MRI scans. The transfer time of each group were compared and analyzed statistically. Additionally, the number and type of imaging performed at the primary care hospital were analyzed. Results: All qualified patients (n=276) were enrolled in this study: 121 patients in group A; 104 in group B; 51 in group C. There was a statistically significant difference in the transfer time between the three groups (p-value<0.001), and 79 (28.6%) were transferred to an emergency medical center within one hour. In group C, CT or MRI scans were performed an average of 1.86 times at the primary care hospital, and the median transfer time was 4 hours 5 minutes. Conclusion: Only 28.6% of the cases in the study arrived within the golden hour at a definitive care facility. Such delays are in part the result of prolonged times at the primary care hospital for radiologic examinations, such as CT or MRI scans. Major multiple trauma patients should be transferred to a definitive care facility directly or as soon as the primary survey and the resuscitation of Advanced Trauma Life Support guideline are completed at the primary care hospital.