• Title/Summary/Keyword: extensions

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A Probabilistic Analysis for Periodicity of Real-time Tasks

  • Delgado, Raimarius;Choi, Byoung Wook
    • International Journal of Internet, Broadcasting and Communication
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    • v.13 no.1
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    • pp.134-142
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    • 2021
  • This paper proposes a probabilistic method in analyzing timing measurements to determine the periodicity of real-time tasks. The proposed method fills a gap in existing techniques, which either concentrate on the estimation of worst-case execution times, or do not consider the stochastic behavior of the real-time scheduler. Our method is based on the Z-test statistical analysis which calculates the probability of the measured period to fall within a user-defined standard deviation limit. The distribution of the measured period should satisfy two conditions: its center (statistical mean) should be equal to the scheduled period of the real-time task, and that it should be symmetrical with most of the samples focused on the center. To ensure that these requirements are met, a data adjustment process, which omits any outliers in the expense of accuracy, is presented. Then, the Z-score of the distribution according to the user-defined deviation limit provides a probability which determines the periodicity of the real-time task. Experiments are conducted to analyze the timing measurements of real-time tasks based on real-time Linux extensions of Xenomai and RT-Preempt. The results indicate that the proposed method is able to provide easier interpretation of the periodicity of real-time tasks which are valuable especially in comparing the performance of various real-time systems.

A Study of Pants Pattern Design for Middle-aged Women Based on the BMI Index -For Women Aged 45 to 59 Years- (BMI 지수에 따른 중년여성의 팬츠패턴 설계연구 -45~59세를 대상-)

  • Lee, Jong Kyu;Lim, Ho Sun
    • Journal of the Korean Society of Clothing and Textiles
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    • v.45 no.3
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    • pp.477-494
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    • 2021
  • This study examined four subjects with close to average body-size values in four stages based on the average BMI value of middle-aged women aged 45 to 59 years. The first experimental pants was developed with two kinds of educational materials pants pattern. After using a clothing-suitability evaluation to identify problems, a pants pattern suitable for the body shape of middle-aged women was developed by modifying and supplementing the initial design. The fit assessment revealed that pattern A had a problem with wrinkles in the hip and thigh areas due to the long crotch length, and pattern B had a short bottom length, which caused the bottom to curl in toward the groin or for the bottom to stick at the hips. The second experimental pants was developed to address these issues and overall satisfaction with the dimensions was higher than for the first educational pattern. The proper front and rear length extensions satisfied movement functionality and appearance requirements, and increasing the gradient of the back centerline-rather than expanding the width of the back crotch-improved the functionality.

RESTRICTION OF SCALARS AND CUBIC TWISTS OF ELLIPTIC CURVES

  • Byeon, Dongho;Jeong, Keunyoung;Kim, Nayoung
    • Journal of the Korean Mathematical Society
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    • v.58 no.1
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    • pp.123-132
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    • 2021
  • Let K be a number field and L a finite abelian extension of K. Let E be an elliptic curve defined over K. The restriction of scalars ResKLE decomposes (up to isogeny) into abelian varieties over K $$Res^L_KE{\sim}{\bigoplus_{F{\in}S}}A_F,$$ where S is the set of cyclic extensions of K in L. It is known that if L is a quadratic extension, then AL is the quadratic twist of E. In this paper, we consider the case that K is a number field containing a primitive third root of unity, $L=K({\sqrt[3]{D}})$ is the cyclic cubic extension of K for some D ∈ K×/(K×)3, E = Ea : y2 = x3 + a is an elliptic curve with j-invariant 0 defined over K, and EaD : y2 = x3 + aD2 is the cubic twist of Ea. In this case, we prove AL is isogenous over K to $E_a^D{\times}E_a^{D^2}$ and a property of the Selmer rank of AL, which is a cubic analogue of a theorem of Mazur and Rubin on quadratic twists.

Blending of Contrast Enhancement Techniques for Underwater Images

  • Abin, Deepa;Thepade, Sudeep D.;Maitre, Amulya R.
    • International Journal of Computer Science & Network Security
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    • v.22 no.1
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    • pp.1-6
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    • 2022
  • Exploration has always been an instinct of humans, and underwater life is as fascinating as it seems. So, for studying flora and fauna below water, there is a need for high-quality images. However, the underwater images tend to be of impaired quality due to various factors, which calls for improved and enhanced underwater images. There are various Histogram Equalization (HE) based techniques which could aid in solving these issues. Classifying the HE methods broadly, there is Global Histogram Equalization (GHE), Mean Brightness Preserving HE (MBPHE), Bin Modified HE (BMHE), and Local HE (LHE). Each of these HE extensions have their own pros and cons and thus, by considering them we have considered BBHE, CLAHE, BPDHE, BPDFHE, and DSIHE enhancement algorithms, which are based on Mean Brightness Preserving HE and Local HE, for this study. The performance is evaluated with non-reference performance measures like Entropy, UCIQE, UICM, and UIQM. In this study, we apply the enhancement algorithms on 300 images from the UIEB benchmark dataset and then apply the techniques of cascading fusion on the best-performing algorithms.

Type 1.5 Split Cord Malformation : A New Theory of Pathogenesis

  • Sun, Mengchun;Tao, Benzhang;Luo, Tianbao;Gao, Gan;Shang, Aijia
    • Journal of Korean Neurosurgical Society
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    • v.65 no.1
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    • pp.138-144
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    • 2022
  • To report two cases of type 1.5 split cord malformation (SCM), a subtype of SCM with combined characteristics of types I and II and to review the relevant literature and propose a new possible pathogenetic theory for type 1.5 SCM. A 52-year-old woman had hemicords within a single dural sac with a dorsal bony septum at the L5 level. A 9-year-old boy had hemicords within a single dural sac with a ventral bony septum and fibrous extension at the L3 level. Both patients underwent microsurgical treatments for removing the bony septum, detethering the spinal cord, and sectioning the filum terminale. The surgical procedure revealed an extradural partial bony septum and hemicords within an intact single dural sac in each patient. Both patients were discharged from the hospital without de novo nerve dysfunction. Published cases have validated that types I and II SCM can overlap. We recommend recent type 1.5 SCM as a normative terminology for this overlapping SCM and report two rare cases of this SCM. We propose an associated pathogenesis consisting of uneven distribution and regression to explain type 1.5 SCM. Furthermore, we postulate that the amount of condensing meninx primitiva might determine whether the left bony septum has fibrous extensions to the opposite dura in type 1.5 SCM.

ORE EXTENSIONS OVER σ-RIGID RINGS

  • Han, Juncheol;Lee, Yang;Sim, Hyo-Seob
    • East Asian mathematical journal
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    • v.38 no.1
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    • pp.1-12
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    • 2022
  • Let R be a ring with an endomorphism σ and a σ-derivation δ. R is called (σ, δ)-Baer (resp. (σ, δ)-quasi-Baer, (σ, δ)-p.q.-Baer, (σ, δ)-p.p.) if the right annihilator of every right (σ, δ)-set (resp., (σ, δ)-ideal, principal (σ, δ)-ideal, (σ, δ)-element) of R is generated by an idempotent of R. In this paper, for a given Ore extension A = R[x; σ, δ] of R, the following properties are investigated: If R is a σ-rigid ring in which σ and δ commute, then (1) R is (σ, δ)-Baer if and only if R is (σ, δ)-quasi-Baer if and only if A is (${\bar{\sigma}},\;{\bar{\delta}}$)-Baer if and only if A is (${\bar{\sigma}},\;{\bar{\delta}}$)-quasi-Baer; (2) R is (σ, δ)-p.p. if and only if R is (σ, δ)-p.q.-Baer if and only if A is (${\bar{\sigma}},\;{\bar{\delta}}$)-p.p. if and only if A is (${\bar{\sigma}},\;{\bar{\delta}}$)-p.q.-Baer.

Study on the Anatomical Meaning of 'Geun(筋)' in 『Yeongchu·Gyeonggeun(靈樞·經筋)』 (《영추(靈樞)·경근(經筋)》에서 근(筋)의 해부학적 의미에 대한 연구)

  • Kim, Min-Sik;Song, Jong-Keun;Kim, Chang-Geon;Kim, So-Rim;Lee, Eun-Yong
    • The Journal of Korean Medicine
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    • v.43 no.1
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    • pp.42-59
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    • 2022
  • Objectives: This study was done to establish the anatomical meaning of the term 'Geun(筋)'. Methods: Through analysis of 《HwangJeNaeGyeong(黃帝內經)》, the meaning of 'Geun(筋)', 'GeunMag(筋膜)', 'Yug(肉)', and 'Gi(肌)' were established. Based on analysis, the anatomical meaning of the 'Meridian-muscle(經筋)' was studied by comparing it with anatomy. Results & Conclusions: 'Gyeong(經)' is recognized as a metaphysical expression and "Geun(筋)" means myofascia in anatomy. The concept of 'Geun(筋)' includes the epimysium and perimysium, as well as tendons and ligaments, which are extensions of these. 'Fascia', refers to the fascia of the whole body, and also appertain to 'Geun(筋)'. 'Yug(肉)' means endomysium, muscle fiber, and adipose tissue and layer. The word 'GeunMag(筋膜)' used in the 《HwangJeNaeGyeong(黃帝內經)》 means anatomically a 'tendon'. Therefore, 'Muscle' should be translated as 'GeunYug(筋肉)' in Traditional medicine. 'Meridian-muscle(經筋)' can be defined as the longitudinal muscle and fascia system, which is the basis of whole body encompassing dynamics.

Two new species of Pseudostaurosiropsis (Bacillariophyta, Fragilariophyceae) from the United States of America, with taxonomic comments on the genus

  • Morales, Eduardo A.
    • ALGAE
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    • v.37 no.1
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    • pp.33-47
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    • 2022
  • Two new species of Pseudostaurosiropsis are described based on material collected from rivers in southern United States of America, P. californicus sp. nov. and P. elaboratus sp. nov. Both species have specific characters that set them apart from taxa currently ascribed to the genus. Pseudostaurosiropsis californicus sp. nov. has lanceolate valves with subrostrate, broadly rounded apices, an axial area at the same level as the virgae in internal and external views and both are at the same level as striae in external view, the spine tips are dentate and their growth is produced by filamentous extensions, and it has equal-sized apical pore fields on both valve extremes. On the other hand, P. elaboratus sp. nov. has heavily silicified valves, the virgae are slender than the striae in outer view and wider in inner view, it only has a single, externally occluded apical pore field on one valve extreme, and the spines have a solid core. All species within Pseudostaurosiropsis are contrasted with one another and unique features are described for each based on literature and newly collected image data from type material. The genus is reconsidered and two distinguishing features are recognized: rotae externally occluding the areolae and areolae that are funnel-shaped. These features are contrasted with those in other genera and additional published species that should be included in Pseudostaurosiropsis are discussed.

Investor Sentiment Timing Ability of Mutual Fund Managers: A Comparative Study and Some Extensions

  • CHUNHACHINDA, Pornchai;WATTANATORN, Woraphon;PADUNGSAKSAWASDI, Chaiyuth
    • Journal of Distribution Science
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    • v.20 no.9
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    • pp.83-95
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    • 2022
  • Purpose: This study aims to explore an ability to time market-wide investor sentiment of mutual fund managers in an emerging market. Research design, data, and methodology: Based on data of Thai mutual fund market over the period of 2000-2019, our sample includes 283 equity funds, consisting of 204 bank-related funds and 79 nonbank-related funds. We perform our regression analyses at the aggregate and portfolio levels. Results: Under the non-normal distribution of return, we find different behaviors between the best- and worst-performing funds in an ability to time market-wide investor sentiment in Thailand, which is dissimilar to the findings in the U.S. Bottom fund managers act as sentiment hedgers, who decrease (increase) an exposure of investment portfolios when the investor sentiment is high (low). Oppositely, top fund managers are likely to chase investor sentiment. Conclusion: We find that only the worst-performing fund managers, especially for bank-related funds are able to time the market-wide investor sentiment. An advantage of gaining information from their bank's clients is a key success. A competition in the mutual fund industry, an ability to predict fundamentals, and financial literacy are possible reasons to explain the main findings found in this study.

Multimedia Document Databases : Representation, Query Processing and Navigation

  • Kalakota, Ravi S.;Whinston, Andrew B.
    • The Journal of Information Technology and Database
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    • v.1 no.1
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    • pp.31-62
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    • 1994
  • Information systems for application areas like office automation, customer service or computer aided manufacturing are usually highly interactive and deal with complex document structures composed of multiple media formats. For the realization of these systems, nonstandard database systems, which we call document databases, need to handle different types of coarse-and fine-grained document objects(like full-text documents, graphics and images), hierarchical and non-hierarchical relationships between objects(like composition-links and cross-references using hypertext structures) and document attributes of different types such as formatting/presentation information and access control. In this paper, we present the underlying data model for document databases based on descriptive markup languages that provide mechanisms for specifying the logical structure(or schema) of individual documents stored in the database. We then describe extensions to the data model for supporting notion of composite structures("join" operators for documents) --composition and hyperlinking mechanisms for representing compound documents and inter-linked documents as unique entites separate from their components. Furthermore, due to the interactive nature of the application domains, the database system in conjunction with clients(or browsers) has to support visual navigation and graphical query mechanisms. We describe the functionality of a new user interface paradigm called HyBrow for meeting the above mentioned requirements. The underlying implementation strategy is also discussed.discussed.

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