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Predicting the CPT-based pile set-up parameters using HHO-RF and PSO-RF hybrid models

  • Yun Dawei;Zheng Bing;Gu Bingbing;Gao Xibo;Behnaz Razzaghzadeh
    • Structural Engineering and Mechanics
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    • v.86 no.5
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    • pp.673-686
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    • 2023
  • Determining the properties of pile from cone penetration test (CPT) is costly, and need several in-situ tests. At the present study, two novel hybrid learning models, namely PSO-RF and HHO-RF, which are an amalgamation of random forest (RF) with particle swarm optimization (PSO) and Harris hawks optimization (HHO) were developed and applied to predict the pile set-up parameter "A" from CPT for the design aim of the projects. To forecast the "A," CPT data along were collected from different sites in Louisiana, where the selected variables as input were plasticity index (PI), undrained shear strength (Su), and over consolidation ratio (OCR). Results show that both PSO-RF and HHO-RF models have acceptable performance in predicting the set-up parameter "A," with R2 larger than 0.9094, representing the admissible correlation between observed and predicted values. HHO-RF has better proficiency than the PSO-RF model, with R2 and RMSE equal to 0.9328 and 0.0292 for the training phase and 0.9729 and 0.024 for testing data, respectively. Moreover, PI and OBJ indices are considered, in which the HHO-RF model has lower results which leads to outperforming this hybrid algorithm with respect to PSO-RF for predicting the pile set-up parameter "A," consequently being specified as the proposed model. Therefore, the results demonstrate the ability of the HHO algorithm in determining the optimal value of RF hyperparameters than PSO.

Has Container Shipping Industry been Fixing Prices in Collusion?: A Korean Market Case

  • Jaewoong Yoon;Yunseok Hur
    • Journal of Korea Trade
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    • v.27 no.1
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    • pp.79-100
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    • 2023
  • Purpose - The purpose of this study is to analyze the market power of the Korea Container Shipping Market (Intra Asia, Korea-Europe, and Korea-U.S.) to verify the existence of collusion empirically, and to answer whether the joint actions of liner market participants in Korea have formed market dominance for each route. Precisely, it will be verified through the Lerner index as to whether the regional market of Asia is a monopoly, oligopoly, or perfect competition. Design/methodology - This study used a Lerner index adjusted with elasticity presented in the New Imperial Organization (NEIO) studies. NEIO refers to a series of empirical studies that estimate parameters to judge market power from industrial data. This study uses B-L empirical models by Bresnahan (1982) and Lau (1982). In addition, NEIO research data statistically contain self-regression and stability problems as price and time series data. A dynamic model following Steen and Salvanes' Error Correction Model was used to solve this problem. Findings - The empirical results are as follows. First, λ, representing market power, is nearly zero in all three markets. Second, the Korean shipping market shows low demand elasticity on average. Nevertheless, the markup is low, a characteristic that is difficult to see in other industries. Third, the Korean shipping market generally remains close to perfect competition from 2014 to 2022, but extreme market power appears in a specific period, such as COVID-19. Fourth, there was no market power in the Intra Asia market from 2008 to 2014. Originality/value - Doubts about perfect competition in the liner market continued, but there were few empirical cases. This paper confirmed that the Korea liner market is a perfect competition market. This paper is the first to implement dynamics using ECM and recursive regression to demonstrate market power in the Korean liner market by dividing the shipping market into Deep Sea and Intra Asia separately. It is also the first to prove the most controversial problems in the current shipping industry numerically and academically.

Clinical and radiological characteristics of odontomas: A retrospective study of 90 cases

  • Dung Kim Nguyen;Duong Van Huynh
    • Imaging Science in Dentistry
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    • v.53 no.2
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    • pp.117-126
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    • 2023
  • Purpose: Odontomas represent a common clinical entity among odontogenic tumors, but are not well-addressed in the Vietnamese population. The present study aimed to determine the clinical and preclinical characteristics of odontomas and associated factors in the Vietnamese population. Materials and Methods: This retrospective study retrieved data from histopathological diagnoses from 2 central hospitals of Odonto-Stomatology in Ho Chi Minh City, Vietnam during 2004-2017. The odontomas were classified as complex (CxOD) or compound (CpOD) subtypes. The epidemiological, clinical, and radiological characteristics of the odontomas, stratified by subtype and sex, were obtained and analyzed. Results: Ninety cases, consisting of 46 CxODs and 44 CpODs, were included. The average age of patients was 32.4 (±20.2) years. The patients with CxOD were older than those with CpOD (P<0.05). Clinically, 67% of patients showed an intraoral bone expansion. Approximately 60% of patients with CxOD exhibited a painful symptom, about 3-fold more than those with CpOD (P<0.05), whereas almost all patients with CpOD exhibited perturbations of dentition, unlike those with CxOD (P<0.05). Radiologically, CxOD was characterized by a larger dimension than CpOD in both sexes (P<0.05), and CpOD induced complications in adjacent teeth more often than CxOD (P<0.05). The development of odontoma with advancing age differed significantly in odontoma subtypes related to their pathological origins, and between the sexes, resulting from different physiological states. Conclusion: The findings of this study highlight the value of clinical and radiological features of odontomas and their associated factors for the early diagnosis and adequate treatment of younger patients.

Characteristics of Cyclic Shear Stress Ratio by Silt Content for Nak-Dong River Sand (낙동강 모래의 실트함유량 변화에 따른 반복전단응력비 특성)

  • Kim, Young-Su;Kim, Dae-Man
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.29 no.6C
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    • pp.277-285
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    • 2009
  • A series of undrained cyclic triaxial tests were carried out to investigate the cyclic shear stress strength characteristics of sands with respect to the silt content. Silty sand was collected around the basin of Nak-Dong River and remolded in laboratory with the range of silt content 0~50% in sand located. As results, with the change of silt content cyclic shear stress ratio (CSR) at N=10 showed the maximum value at 5% and the minimum at 20% in all relative density. The development tendency of the pore water pressure analyzed by the relationship cyclic ratio and pore water pressure ratio is unrelated the change of CSR varying silt content. Comparing the results of the void ratio and skeleton void ratio after consolidation, CSR varying silt content was much affected by skeleton void ratio which is known to affect shear behavior of silty sand.

Economic Feasibility Analysis for Introducing Integrated Management System for Supporting Underground Construction (지하구조물건설 현장지원 통합관리시스템 도입을 위한 경제적 타당성 분석)

  • Baek, Hyeon Gi;Jang, Yong Gu;Seo, Jong Won
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.30 no.5D
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    • pp.513-522
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    • 2010
  • Underground construction for traffic networks, complexes, and storage facilities has risen as an effective land use plan for dealing with emerging problems such as overcrowded urban cities and traffic jams. This paper performed an economic feasibility analysis of the development of the integrated field management system which provides field workers and managers with 3D-based location tracking and clear communication during underground construction works. To conduct the analysis, processes and problems of field management for underground construction were analyzed and deduction in accidents and field management costs and productivity improvement were estimated as expected benefits. Based on computed benefits and costs, an economic analysis was conducted using Benefit/Cost ratio(B/C), Net Present Value(NPV), and Internal Rate of Return(IRR) and then sensitivity analysis was performed to cope with the uncertainty of assumed variables.

The Function of the Author and the Poetic Experiments in Lyrical Ballads of 1798 (1798년 『서정민요집』의 저자의 기능과 시적 실험)

  • Joo, Hyeuk Kyu
    • Journal of English Language & Literature
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    • v.56 no.5
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    • pp.973-998
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    • 2010
  • This paper aims at assessing the significance of Lyrical Ballads of 1798, the agreed inaugurator of English Romanticism, in terms of such key concepts as poetic "experiments," "conversation," and the authorial function. The 1798 volume marks an interesting incidence in which an author with no tangible substantiality can wield his authorial function over his works. The volume is signed without the named proper noun-its author is neither William Wordsworth nor Samuel Taylor Coleridge. The figure of the author in this case is realized by the poems he writes; he produces, and is produced by, his works-a fact that constitutes part of the poetic experiments manifested in the Advertisement. Working under this reciprocal production, the Author of the 1798 volume and his poems are collectively aiming at establishing a new class of poetry and an interpretive community. The notion of "conversation" is a key element in the thematic, stylistic ties among individual poems. Poems of the 1798 volume effect multi-layered, "blended" voices. Readers are expected to draw out the topological interweaving among poems through the practices of dialogic reading. In this light, the sequential necessity of "The Rime" and "Tintern Abbey" should be emphasized. They are stitched together in a logic of textual placement and the transition from one to the other is never arbitrary. Most of all, they are working under the same authorial function, complementing each other, and addressing the same poetic project in different textual locations. As an inaugural work of English Romanticism, Lyrical Ballads of 1798 in fact makes so many things happen and yet again anticipates something yet to come with elusiveness. The value of this poetic experiments should be judged not only by what is claimed in it, but what it sets out to do and "how far" it will be performed, as implied in the Advertisement. The efficacy of the volume, more than anything else, is dependent upon the performative power of words.

A Study on Drift Phenomenon of Trained ML (학습된 머신러닝의 표류 현상에 관한 고찰)

  • Shin, ByeongChun;Cha, YoonSeok;Kim, Chaeyun;Cha, ByungRae
    • Smart Media Journal
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    • v.11 no.7
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    • pp.61-69
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    • 2022
  • In the learned machine learning, the performance of machine learning degrades at the same time as drift occurs in terms of learning models and learning data over time. As a solution to this problem, I would like to propose the concept and evaluation method of ML drift to determine the re-learning period of machine learning. An XAI test and an XAI test of an apple image were performed according to strawberry and clarity. In the case of strawberries, the change in the XAI analysis of ML models according to the clarity value was insignificant, and in the case of XAI of apple image, apples normally classified objects and heat map areas, but in the case of apple flowers and buds, the results were insignificant compared to strawberries and apples. This is expected to be caused by the lack of learning images of apple flowers and buds, and more apple flowers and buds will be studied and tested in the future.

Rewriting Georgic: Anna Letitia Barbauld's "Washing-Day" (죠직 다시 쓰기 -아나 레티셔 바볼드의 「빨래하는 날」)

  • Shin, Kyung-Sook
    • Journal of English Language & Literature
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    • v.56 no.5
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    • pp.947-971
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    • 2010
  • Anna Letitia Barbauld's poem "Washing-Day" (1797) has sparked a variety of feminist critical endeavors over the past two decades. While many feminist literary critics try to salvage the poem as a successful tongue-in-cheek riposte directed at the male dominant literary world, more rigorous Marxist feminists accuse Barbauld of being limited by her own middle-class woman's view on women's domestic labor. Legitimate as they may be, these readings fail to elucidate Barbauld's place in a larger literary and intellectual discourse during the eighteenth century. In this paper I read "Washing-Day" as a woman's georgic, a genre or mode concerned with agricultural labor, the public value of which was highly recognized in eighteenth-century England. Alluding to canonical texts by writers like Shakespeare, Milton, and Pope, Barbauld's "loaded lines" in mock-heroic form create a space in which the women's domestic labor of washing interrupts men's daily routines and disrupts their poetic assumptions. While she makes women's work visible, Barbauld also addresses its quintessential nature. Women's work is affective labor; women have to labor physically and mentally to produce the desired domestic comfort. By allowing the image of the soap "bubble" to echo with many "bubbles" in other writers' texts, from the soap bubbles the narrator used to play with as a child to the hot-air balloon "bubble" of the Montgolfier brothers, Barbauld pleasantly equates work and day-dreaming, men's toil and children's play, and finally public, scientific, and recognized labor and private, domestic, and imaginative activities.

Literary Texts in the English Classroom: An Integrated Approach to English Instruction (영어 교실의 문학 텍스트 -영어교육의 통합적 접근)

  • Kang, Gyu Han
    • Journal of English Language & Literature
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    • v.55 no.1
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    • pp.107-128
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    • 2009
  • Literature had been at center-stage in the traditional grammar-translation-focused English classrooms up to the mid-twentieth century. As the Audiolingual Method and the Communicative Language Teaching have gained popularity in the English classrooms, however, literature has receded into the background of English education. The main reasons for using literary texts in the English classrooms for communication-focused English instruction need to be examined. First of all, students can come in touch with the subtle and varied uses of language through literature-based teaching. They also feel close to certain characters in the literary work and share the emotional reponses with them. They get personally involved in the plot of the story. Universal human experience and cultural enrichment are two other merits which can be conferred on students by literary texts. Such linguistic and literary experiences can be significantly integrated into the literature-based instruction. More significantly, the four language skills (reading, writing, listening and speaking) can be combined with one another and integrated into a literature-focused curriculum for English education. The value of literary texts in the English classrooms can be clearly demonstrated by effective ways of using such texts as Charlotte's Web for integrated instruction. The full array of benefits that literature can bring to English instruction, however, has yet to be fully realized. These potentials need to be materialized into classroom practice.

The influence of sodium hypochlorite concentration on the fibrin structure of human blood clots and transforming growth factor-beta 1 release: an ex vivo study

  • Anisha Mishra ;Velmurugan Natanasabapathy;Nandini Suresh
    • Restorative Dentistry and Endodontics
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    • v.47 no.4
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    • pp.42.1-42.11
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    • 2022
  • Objective: This study investigated the effects of various concentrations of sodium hypochlorite (NaOCl) on human whole-blood clotting kinetics, the structure of the blood clots formed, and transforming growth factor (TGF)-β1 release. Materials and Methods: Human whole blood was collected from 5 healthy volunteers and divided into 4 groups: CG (control, 0.5 mL of blood), BN0.5 (0.5 mL of blood with 0.5 mL of 0.5% NaOCl), BN3 (0.5 mL of blood with 0.5 mL of 3% NaOCl), and BN5.25 (0.5 mL of blood with 0.5 mL of 5.25% NaOCl). The effects of NaOCl on clotting kinetics, structure of fibrin and cells, and release of TGF-β1 were assessed using thromboelastography (TEG), scanning electron microscopy (SEM), and enzyme-linked immunosobent assay, respectively. Statistical analysis was conducted using the Kruskal Wallis and Mann-Whitney U tests, followed by the post hoc Dunn test. A p value < 0.05 indicated statistical significance. Results: The blood samples in BN0.5 and BN3 did not clot, whereas the TEG of BN5.25 showed altered clot formation. Samples from the CG and BN3 groups could only be processed with SEM, which showed that the latter lacked fibrin formation and branching of fibers, as well as clumping of red blood cells with surface roughening and distortion. TGF-β1 release was significantly highest in BN3 when all groups were compared to CG (p < 0.05). Conclusions: Each concentration of NaOCl affected the release of TGF-β1 from blood clots and altered the clotting mechanism of blood by affecting clotting kinetics and cell structure.