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The World as Seen from Venice (1205-1533) as a Case Study of Scalable Web-Based Automatic Narratives for Interactive Global Histories

  • NANETTI, Andrea;CHEONG, Siew Ann
    • Asian review of World Histories
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    • v.4 no.1
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    • pp.3-34
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    • 2016
  • This introduction is both a statement of a research problem and an account of the first research results for its solution. As more historical databases come online and overlap in coverage, we need to discuss the two main issues that prevent 'big' results from emerging so far. Firstly, historical data are seen by computer science people as unstructured, that is, historical records cannot be easily decomposed into unambiguous fields, like in population (birth and death records) and taxation data. Secondly, machine-learning tools developed for structured data cannot be applied as they are for historical research. We propose a complex network, narrative-driven approach to mining historical databases. In such a time-integrated network obtained by overlaying records from historical databases, the nodes are actors, while thelinks are actions. In the case study that we present (the world as seen from Venice, 1205-1533), the actors are governments, while the actions are limited to war, trade, and treaty to keep the case study tractable. We then identify key periods, key events, and hence key actors, key locations through a time-resolved examination of the actions. This tool allows historians to deal with historical data issues (e.g., source provenance identification, event validation, trade-conflict-diplomacy relationships, etc.). On a higher level, this automatic extraction of key narratives from a historical database allows historians to formulate hypotheses on the courses of history, and also allow them to test these hypotheses in other actions or in additional data sets. Our vision is that this narrative-driven analysis of historical data can lead to the development of multiple scale agent-based models, which can be simulated on a computer to generate ensembles of counterfactual histories that would deepen our understanding of how our actual history developed the way it did. The generation of such narratives, automatically and in a scalable way, will revolutionize the practice of history as a discipline, because historical knowledge, that is the treasure of human experiences (i.e. the heritage of the world), will become what might be inherited by machine learning algorithms and used in smart cities to highlight and explain present ties and illustrate potential future scenarios and visionarios.

Centroidal Voronoi Tessellation-Based Reduced-Order Modeling of Navier-Stokes Equations

  • 이형천
    • Proceedings of the Korean Society of Computational and Applied Mathematics Conference
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    • 2003.09a
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    • pp.1-1
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    • 2003
  • In this talk, a reduced-order modeling methodology based on centroidal Voronoi tessellations (CVT's)is introduced. CVT's are special Voronoi tessellations for which the generators of the Voronoi diagram are also the centers of mass (means) of the corresponding Voronoi cells. The discrete data sets, CVT's are closely related to the h-means clustering techniques. Even with the use of good mesh generators, discretization schemes, and solution algorithms, the computational simulation of complex, turbulent, or chaotic systems still remains a formidable endeavor. For example, typical finite element codes may require many thousands of degrees of freedom for the accurate simulation of fluid flows. The situation is even worse for optimization problems for which multiple solutions of the complex state system are usually required or in feedback control problems for which real-time solutions of the complex state system are needed. There hava been many studies devoted to the development, testing, and use of reduced-order models for complex systems such as unsteady fluid flows. The types of reduced-ordered models that we study are those attempt to determine accurate approximate solutions of a complex system using very few degrees of freedom. To do so, such models have to use basis functions that are in some way intimately connected to the problem being approximated. Once a very low-dimensional reduced basis has been determined, one can employ it to solve the complex system by applying, e.g., a Galerkin method. In general, reduced bases are globally supported so that the discrete systems are dense; however, if the reduced basis is of very low dimension, one does not care about the lack of sparsity in the discrete system. A discussion of reduced-ordering modeling for complex systems such as fluid flows is given to provide a context for the application of reduced-order bases. Then, detailed descriptions of CVT-based reduced-order bases and how they can be constructed of complex systems are given. Subsequently, some concrete incompressible flow examples are used to illustrate the construction and use of CVT-based reduced-order bases. The CVT-based reduced-order modeling methodology is shown to be effective for these examples and is also shown to be inexpensive to apply compared to other reduced-order methods.

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Heat Transfer Characteristics of 2 t/h-Class Modular Water-Tube-Type Boiler (모듈형 2 t/h급 수관식 보일러의 열전달 특성)

  • Ahn, Joon;Hwang, Sang-Soon;Kim, Jong-Jin;Kang, Sae-Byul
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.36 no.11
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    • pp.1127-1133
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    • 2012
  • A finned-tube-type evaporator module has been proposed for a 2 t/h-class water-tube-type industrial boiler with multiple burners. The geometry of the fins was changed at each module to equalize the evaporation. The modules were designed by considering the energy balance at each row rather than by following a conventional bulk design procedure. The designed module was built into a 2 t/h-class water-tube-type boiler, and its performance was tested. A numerical simulation was also conducted to evaluate the two- or three-dimensional effects of factors such as the inlet conditions. The numerical simulation also included the conjugate heat transfer problem to predict the fin tip temperature. The heat transfer coefficient with fins is lower than that obtained from the empirical correlation of a bare tube. The fin tip temperature from CFD is higher than that from the analytical solution.

Energy-Aware Self-Stabilizing Distributed Clustering Protocol for Ad Hoc Networks: the case of WSNs

  • Ba, Mandicou;Flauzac, Olivier;Haggar, Bachar Salim;Makhloufi, Rafik;Nolot, Florent;Niang, Ibrahima
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.7 no.11
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    • pp.2577-2596
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    • 2013
  • In this paper, we present an Energy-Aware Self-Stabilizing Distributed Clustering protocol based on message-passing model for Ad Hoc networks. The latter does not require any initialization. Starting from an arbitrary configuration, the network converges to a stable state in a finite time. Our contribution is twofold. We firstly give the formal proof that the stabilization is reached after at most n+2 transitions and requires at most $n{\times}log(2n+{\kappa}+3)$ memory space, where n is the number of network nodes and ${\kappa}$ represents the maximum hops number in the clusters. Furthermore, using the OMNeT++ simulator, we perform an evaluation of our approach. Secondly, we propose an adaptation of our solution in the context of Wireless Sensor Networks (WSNs) with energy constraint. We notably show that our protocol can be easily used for constructing clusters according to multiple criteria in the election of cluster-heads, such as nodes' identity, residual energy or degree. We give a comparison under the different election metrics by evaluating their communication cost and energy consumption. Simulation results show that in terms of number of exchanged messages and energy consumption, it is better to use the Highest-ID metric for electing CHs.

Power Allocation Optimization and Green Energy Cooperation Strategy for Cellular Networks with Hybrid Energy Supplies

  • Wang, Lin;Zhang, Xing;Yang, Kun
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.10 no.9
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    • pp.4145-4164
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    • 2016
  • Energy harvesting is an increasingly attractive source of power for cellular networks, and can be a promising solution for green networks. In this paper, we consider a cellular network with power beacons powering multiple mobile terminals with microwave power transfer in energy beamforming. In this network, the power beacons are powered by grid and renewable energy jointly. We adopt a dual-level control architecture, in which controllers collect information for a core controller, and the core controller has a real-time global view of the network. By implementing the water filling optimized power allocation strategy, the core controller optimizes the energy allocation among mobile terminals within the same cluster. In the proposed green energy cooperation paradigm, power beacons dynamically share their renewable energy by locally injecting/drawing renewable energy into/from other power beacons via the core controller. Then, we propose a new water filling optimized green energy cooperation management strategy, which jointly exploits water filling optimized power allocation strategy and green energy cooperation in cellular networks. Finally, we validate our works by simulations and show that the proposed water filling optimized green energy cooperation management strategy can achieve about 10% gains of MT's average rate and about 20% reduction of on-grid energy consumption.

A Historical Study on the Treatments of 鼻鼽(bí qiú) ('비구(鼻鼽)'에 대한 의사학적 연구)

  • Oh, Byung-Gun;Maeng, Woong-Jae;Kim, Hoon
    • The Journal of Korean Medical History
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    • v.24 no.1
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    • pp.97-110
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    • 2011
  • Rhinitis, inflammation of the nasal cavity caused by the disease in our country that a recent trend is the rapidly increasing number of patients. It causes multiple complications and interfere with daily life and social life in case of being viewed as a mild cold. The rhinitis treatment for symptomatic therapy in modern medicine is staying because the situation is exposing the limitations. so traditional medicine is trying to find a solution but that is not easy. In modern medicine, rhinitis is defined as a set of histological lesions and clinical symptoms, but traditional medicine has developed in dealing with each symptoms in disease. The treatment that doesn't distinguish any treatment in growing numbers of patients does not seem to validate, because doctors treat without considering the difference of recognition. Looking at the symptoms for each, I found that each symptoms and causes are varied according to doctors and era. In spite of considering all of that in treatment, it was ignored or underestimated in modern medicine. Furthermore, in traditional medicine, they just conjugated certain period theory and only had limited treatment by a lack of integrated awareness about definition and mechanism. In addition, in case of mentioning about the causes of prescription in each medical books, there were not enough explain about pathological states. Therefore, these causes should be made to further the research about the validity, pathogenesis and treatment. We can see that theory could be established and modified by the accumulation of clinical experience, observations through classification by each of the causes, prescription and treatment. In traditional medicine simply does not pay attention only to nasal inflammation, such as the impact of Meridian and organs considered to have focused on the fundamental treatment. This increased immune resistance to the modern rhinitis patients may offer new therapeutic approaches. I hope this paper would be helpful to find the treatment with uncovered theory in modern medicine.

Isotope Measurement of Uranium at Ultratrace Levels Using Multicollector Inductively Coupled Plasma Mass Spectrometry

  • Oh, Seong-Y.;Lee, Seon-A.;Park, Jong-Ho;Lee, Myung-Ho;Song, Kyu-Seok
    • Mass Spectrometry Letters
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    • v.3 no.2
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    • pp.54-57
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    • 2012
  • Mass spectrometric analysis was carried out using multicollector inductively coupled plasma mass spectrometry (MC-ICP-MS) for the precise and accurate determination of the isotope ratios of ultratrace levels of uranium dissolved in 3% $HNO_3$. We used the certified reference material (CRM) 112-A at a trace level of 100 pg/mL for the uranium isotopic measurement. Multiple collectors were utilized for the simultaneous measurement of uranium isotopes to reduce the signal uncertainty due to variations in the ion beam intensity over time. Mass bias correction was applied to the measured U isotopes to improve the precision and accuracy. Furthermore, elemental standard solution with certified values of platinum, iridium, gold, and thallium dissolved in 3% $HNO_3$ were analyzed to investigate the formation rates of the polyatomic ions of $Ir^{40}$ $Ar^+$, $Pt^{40}$ $Ar^+$, $Tl^{40}$ $Ar^+$, $Au^{40}$ $Ar^+$ for the concentration range of 50-400 pg/mL. Those polyatomic ions have mass-to-charge ratios in the 230-245 m/z region that it would contribute to the increase of background intensity of uranium, thorium, plutonium, and americium isotopes. The effect of the polyatomic ion interference on uranium isotope measurement has been estimated.

Microcystic Adnexal Carcinoma of the Lower lip: A Case Report (하구순부에 발생한 미세낭포성 피부부속기 암의 치험례)

  • Lee, Chae Su;Rah, Dong Kyun;Kim, Sang Kyum;Tark, Kwan Chul
    • Archives of Plastic Surgery
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    • v.35 no.3
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    • pp.329-332
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    • 2008
  • Purpose: Microcystic adnexal carcinoma is a rare malignant appendage tumor, first described by Goldstein et al in 1982. Here, we present our experience in treatment of a case on the lower lip. Methods: A 52-year-old female with an asymptomatic nodule on the chin, previously misdiagnosed as trichoadenoma by needle aspiration biopsy, was treated by wide excision combined with multiple circumferential frozen biopsies. Results: Pathological examination revealed typical features of microcystic adnexal carcinoma, such as basaloid and squamous cells forming nests and cord-like patterns, horn cysts, and minimal cytologic atypia. The patient has been followed up for 6 months. No sign of recurrence is noted to date. Conclusion: Differentiation from other benign adnexal neoplasms is important for its appropriate treatment. Differentiation can be difficult histologically because it is difficult to acquire an adequate biopsy due to its invasiveness, and clinically due to its asymptomatic and slow growing features. Complete excision is the key treatment, but it may not always be the best solution considering the huge defect that may result and the low incidence of metastasis & deaths owing to the tumor. We add this case to the approximately 300 cases reported worldwide with a review of literature.

Practical Considerations for Perforator Flap Thinning Procedures Revisited

  • Prasetyono, Theddeus O.H.;Bangun, Kristaninta;Buchari, Frank B.;Rezkini, Putri
    • Archives of Plastic Surgery
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    • v.41 no.6
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    • pp.693-701
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    • 2014
  • Background A thin perforator flap is one of the best methods for covering defects. This study aimed to revisit and further test the rapidly advancing field of flap thinning techniques. Methods We performed two cadaveric studies to test the known flap thinning methods, and then applied these methods to a clinical series. In the first study, five cadavers were used to observe the anatomical relation of the perforator with the subdermal plexuses and the subcutaneous fat layer by injecting a colored latex solution. The second study was done on four cadavers independently from the first study. Last, a clinical series was performed on 15 patients. Results The areolar fat lobules of 10 anterolateral thigh perforator (ALT), seven deep inferior epigastric artery perforator (DIEAP), and six thoracodorsal artery perforator (TAP) flaps were dissected to reduce the flap thickness guided by the colored vascular pattern. On average, the ALT, DIEAP, and TAP flaps were reduced to $32.76%{\pm}9.76%$, $37.01%{\pm}9.21%$, and $35.42%{\pm}9.41%$, respectively. In the second study, the areolar fat lobules were directly dissected in six ALT, six TAP, and four MSAP flaps, and an average reduction in flap thickness of $53.41%{\pm}5.64%$, $52.30%{\pm}2.88%$, and $47.87%{\pm}6.41%$, respectively, was found. In the clinical series, 13 out of the 15 cases yielded satisfactory outcomes with an average thickness reduction of $37.91%{\pm}7.15%$. Conclusions These multiple studies showed that the deep fat layer could be safely removed to obtain a thin yet viable perforator flap. This evidence suggests that the macroscopic flap thinning technique can achieve thin flaps. Surgeons should consider this technique before embracing the latest technique of supermicrosurgery.

Stochastic Optimization Approach for Parallel Expansion of the Existing Water Distribution Systems (추계학적 최적화방법에 의한 기존관수로시스템의 병열관로 확장)

  • Ahn, Tae-Jin;Choi, Gye-Woon;Park, Jung-Eung
    • Water for future
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    • v.28 no.2
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    • pp.169-180
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    • 1995
  • The cost of a looped pipe network is affected by a set of loop flows. The mathematical model for optimizing the looped pipe network is expressed in the optimal set of loop flows to apply to a stochastic optimization method. Because the feasible region of the looped pipe network problem is nonconvex with multiple local optima, the Modified Stochastic Probing Method is suggested to efficiently search the feasible region. The method consists of two phase: i) a global search phase(the stochastic probing method) and ii) a local search phase(the nearest neighbor method). While the global search sequentially improves a local minimum, the local search escapes out of a local minimum trapped in the global search phase and also refines a final solution. In order to test the method, a standard test problem from the literature is considered for the optimal design of the paralled expansion of an existing network. The optimal solutions thus found have significantly smaller costs than the ones reported previously by other researchers.

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