• Advances in aircraft and spacecraft science
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• v.8 no.1
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• pp.31-51
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• 2021

Selective laser melting (SLM), one of the most widely used powder bed fusion (PBF) additive manufacturing (AM) technology, enables the fabrication of customized metallic parts with complex geometry by layer-by-layer fashion. However, SLM inherently poses several problems such as the discontinuities in the molten track and the steep temperature gradient resulting in a high degree of residual stress. To avoid such defects, thisstudy proposes a temperature thread multiscale model of SLM for the evaluation of the process at different scales. In microscale melt pool analysis, the laser beam parameters were evaluated based on the predicted melt pool morphology to check for lack-of-fusion or keyhole defects. The analysis results at microscale were then used to build an equivalent body heat flux model to obtain the residual stress distribution and the part distortions at the macroscale (part level). To identify the source of uneven heat dissipation, a liquid lifetime contour at macroscale was investigated. The predicted distortion was also experimentally validated showing a good agreement with the experimental measurement.

• Asia Pacific Journal of Corpus Research
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• v.2 no.2
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• pp.1-15
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• 2021

The study aims to explore the use of metadiscourse in the Bank Negara Malaysia Governor's speeches based on Hyland's Interpersonal Model of Metadiscourse. The corpus data consist of 343 speech texts, which were extracted from the Malaysian Corpus of Financial English (MacFE), amounting to 688,778 tokens. Adopting both quantitative and qualitative approaches to data analysis the study investigates (1) the overall use of metadiscourse in the Bank Negara Governor's speech texts and (2) the functions of the most prominent metadiscourse resources used and their functions in the speech texts. The findings reveal that the Governor's speech texts to be interactional rather than interactive, revealing a rich distribution of interactional metadiscourse resources, namely engagement markers, self-mention, hedges, boosters and attitude markers throughout the texts. The interactional metadiscourse resources function to establish speaker-audience engagement and alignment of views, as well as to express degree of uncertainty and certainty and attitudes. The study concludes that the speech texts are not merely informational or propositional, but rather interpersonal.

• The Journal of Asian Finance, Economics and Business
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• v.9 no.8
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• pp.37-45
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• 2022

This study attempts to understand the relationship between accounting information systems AIS and firms' performance; in the first part of the study, a brief introduction that focuses on the technological advancements and the impact of such advancements on the business world, and in the second part, a review of literature that considered different perspectives on the relationship between AIS and firms' performance. The key differences between manual and automated systems were shown in a table later in the literature review, followed by explanations for each comparison aspect. In the third part, four questions are asked regarding the AIS implementation; the questions covered the top management commitment, the users' competencies, the quality of the adopted system, and the impact of the degree of technological investment on the implementation process. Data for the study was acquired from a Saudi SME. The study's purpose is to investigate the impact of AIS on organizational performance in Saudi SMEs. The presented ideas of this study, where the main finding of the study is that AIS implementation has a positive impact on firms' performance.

• Bulletin of the Society of Naval Architects of Korea
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• v.13 no.2
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• pp.13-43
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• 1976

A potential flow approach is used to develop a method and an associated computer program for floating marine structures of general configuration in wave of all water depths with arbitrary heading. It computes the total force distributions and six degrees-of-freedom motion. The hydrodynamic-force equations and derived become identical under certain assumptions to the equations commonly used by the offshore industry, and the two methods are compared in detail. The computed motions of all six degree agree quite well with model-scale and full-scale experimental data for two typical semisubmersible drilling rigs in finite-depth water. Also the presented motion computations are more accurate than a previous work by the second approach. The present computations use experimentally validated or determined values of frequency-dependent hydrodynamic coefficients with the effects of the free surface and both finite and infinite water depths. The present method generates sufficient computation accuracy to use for practical design applications.

• International conference on construction engineering and project management
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• 2022.06a
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• pp.18-24
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• 2022

State highway agencies (SHAs) typically apply a competitive procurement procedure to select contractors for their design-bid-build projects. Since the level of competition affects construction bid prices and project outcomes, the Federal Highway Agency (FHWA) suggests SHAs seek ways to improve competition among contractors continuously. However, they rarely conduct an empirical assessment of the current competition level necessary to identify room for improvement. Besides the number of bidders on a project, other factors such as winning or losing rates among the contractors in previous projects can also indicate the degree of competition; only a few contractors may have won the majority of the projects in a specific region. However, few studies have investigated such factors. This paper proposes a network analysis-based approach to evaluating contractor competition levels of highway projects using historical bid tabulation data. The proposed method provides insights into overall competition levels, the determination of competitive contractors, and winning rate distribution among contractors.

• Korean Journal of Mathematics
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• v.31 no.2
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• pp.145-152
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• 2023

Let $P(z):=\sum\limits^{n}_{j=0}A_jz^j$, A_j ∈ ℂ^m×m, 0 ≤ j ≤ n be a matrix polynomial of degree n, such that A_n ≥ A_n-1 ≥ . . . ≥ A₀ ≥ 0, A_n > 0. Then the eigenvalues of P(z) lie in the closed unit disk. This theorem proved by Dirr and Wimmer [IEEE Trans. Automat. Control 52(2007), 2151-2153] is infact a matrix extension of a famous and elegant result on the distribution of zeros of polynomials known as Eneström-Kakeya theorem. In this paper, we prove a more general result which inter alia includes the above result as a special case. We also prove an improvement of a result due to Lê, Du, Nguyên [Oper. Matrices, 13(2019), 937-954] besides a matrix extention of a result proved by Mohammad [Amer. Math. Monthly, vol.74, No.3, March 1967].

• Journal of the Korean Society of Systems Engineering
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• v.19 no.1
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• pp.14-28
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• 2023

The spin-off where the principal technology developers take the lead in the active and initiative pursuit of the commercialization of technologies is increasingly drawing attention, breaking away from the traditional means through the technology transfer or licensing of the public technologies created by the developers. This study aimed to determine the reasons for such differences from the perspective of the institutional theory. The results show that only the start-up support system, profit distribution system for researchers, degree of participation in the technology marketing, entrepreneurship of researchers, the use of start-up systems affected the number of start-ups of spin-off companies. Furthermore, an analysis of success factors and a study on the exploration of success paths for the RSOs will also be required

• Asia Marketing Journal
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• v.1 no.3
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• pp.12-33
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• 1999

Recently, consumer researchers have been interested in consumption ritual that expressed condensedly the consumption system in a culture. From various disciplines this study examined the 'ritual' and 'ritualized behavior' which are unique to human beings and analyzed the relation of ritualization of consumption experience and buying behavior. According to the degree of ritualization, consumers were categorized into four types - ritualized, habitualized, involved, and non-ritualized consumers. In the empirical study, the relation between ritualization of "dressing-up (i.e. to put on the clothing with the intention of wearing displaying them publicity)" and buying behaviors related to clothing was explored through in-depth interviews and a questionnaire survey with 434 married Korean women. Through statistical analysis, research questions were identified in an empirical study: as the consumption experience becomes more ritualized, the purchasing frequency, ongoing involvement, brand loyalty, and opinion leadership will increase as part of clothing buying behavior. Herein, the implications of the study and further research issues are discussed.

• Journal of Distribution Science
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• v.14 no.2
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• pp.47-56
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• 2016

Purpose - The purpose of this study is to investigate the difference in the degree of significance and satisfaction perceived by college students and ordinary consumers on the HMR product attributes. Comparison of the difference on HMR product attributes between ordinary consumers and college students who belong to the current and future consumption groups of HMR will provide information for clear marketing strategies and PR on target consumers from the aspects of companies. Also, overall difference on HMR was investigated through IPA(importance-performance analysis) on significance and satisfaction with each product attribute. This result will provide information to food companies that produce or supply HMR products to be supplemented and improved. Finally, IPA was conducted between groups on product attribute to find which difference exists between groups. This result is also expected to provide crucial information to companies as suggested in the first purpose. Research design, data, and methodology - The procedure of analysis is as follows. First, independent sample t-test was conducted on the significance and satisfaction on HMR product attributes. Second, with using IPA, the significance and satisfaction on HMR product attributes of the respondents were checked to investigate marketing strategy direction on overall HRM products. Third, the difference between generations was verified using IPA on the college student and consumer groups. According to this result, the direction of marketing strategy on HRM products was to be proposed to food companies. Results - It was known that consumers consider HMR product attributes statistically and significantly such as nutrient content(nutrition), country of origin, brand, main raw material, packaging, and awareness of manufacturer. They keep after purchase more importantly than college students who considered only volume and price than consumers. In comparison with the difference in satisfaction on HMR product attributes, the college student group was more satisfied than ordinary consumers only in flavor, condition of food additives, and volume. Also, HMR related food companies must maintain taste, cooking method, manufacturing date, expiration date, and safety on current products continuously. Finally, as a result of analysis from the groups, the attributes such as cooking method, manufacturing date, expiration date, and safety were considered significantly with high achievement by the two groups. It was known that college students considered food texture to be important, but consumers considered storage method to be important after purchasing it. Conclusions - There is necessity to differentiate effectiveness of products when releasing HMR products subject to consumers and college students. The result will give great assistance to the improvement of companies, produce or supply HMR products. It will also provide entry strategies on target groups of companies that are planning for entry. The factors that consumers commonly considered not to be significant were brand, package form(appearance), cooking time, and sale(purchase) location, which were found in the comparison with the groups that awareness about manufacturers and storage method after purchase corresponded to college students and that distribution route corresponded to ordinary consumers.

• Progress in Medical Physics
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• v.8 no.1
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• pp.17-24
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• 1997

We developed PC-based planning system for linear accelerator based stereotactic radiosurgery. The system was developed under Windows 95 on Pentium Pro$\^$(R) 200 ㎒ IBM PC with 128 MB RAM. It was programed using IDL$\^$(R)/ of Research Systems, Inc. as a programing tool. CT image data obtained with BRW stereotactic frame is transferred to PC through magnetoptical disk. As loading the image, the system automatically recognizes the location of rods and establishes stereotactic coordinates. It accurately calculates and corrects the coordinates, degree of tilting, and magnification rate of axial images. After the coordinates is defined we can delineate and edit the contours of target and organs of interest on axial images. Upon delineating contours of target, isocenter is determined automatically and we can set up the beam configuration for radiosurgery. The system provides beam's eye view and room's eye view for efficient confuguring of beams. The system calculates dose distribution 3-dimensionally. It takes 1 to 2 minutes to calculate dose distribution for 5 arcs. We can verify the dose distribution on serial axial images. We can analyze the dose distribution quantitatively by evaluation of dose-volume histogram of target and organ of interest. This system, PC-based radiosurgery planning system, includes the basic features for radiosurgery planning and calculates dose distribution within reasonable time for clinical application.