• The Transactions of the Korea Information Processing Society
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• v.13 no.9
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• pp.413-420
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• 2024

RISC-V is an open-source instruction set architecture, used in various hardware implementations, and can be flexibly expanded to meet system requirements through the RV64I base instruction set and 16 standard extensions. Currently, the RISC-V architecture employs the shadow stack technique to protect return addresses. This paper compares the performance of the compact shadow stack mechanism and the parallel shadow stack mechanism in the RISC-V architecture using the SPEC CPU 2017 and beebs benchmarks. Experimental results show that the parallel shadow stack mechanism exhibits higher overhead than the compact shadow stack mechanism. This suggests that the efficiency of the parallel mechanism is reduced due to the limitations of the RISC-V architecture, making the compact shadow stack more suitable for RISC-V. Additionally, this paper identifies the security limitations of the existing RISC-V shadow stack and proposes directions for enhancing the performance and security of shadow stack mechanisms to ensure a secure execution environment for RISC-V.

• Journal of Korean Society of Forest Science
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• v.48 no.1
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• pp.40-50
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• 1980

This research was carried out to examine the substitutional feasibility of low-priced materials produced in waste of forest instead of wheat flour which is extended for plywood adhesives. Wheat, pine bark, wood flour and pine foliage of coniferous trees or poplar foliage of hardwood species were selected and pulverized into 60-100 mesh minute powder after they were dried at $100-105^{\circ}C$ during 24 hours in the drying oven. The prepared particles as above were added to urea formaldehyde resin, urea-melamine copolymer resin and water soluble phenol formaldehyde resin in the ratio of 10, 20, 30 and 50%. After plywoods were processed by the above extending ratios, shear strength of extended plywoods were analyzed and discussed. The results obtained at this study were summarised as follows; 1. In the case of urea formaldehyde resin, both dry and wet shear strength of plywoods extended by wheat flour were shown the highest value. 2. Dry shear strength of urea-melamine copolymer resin was better than that of urea formaldehyde resin on the whole, while plywoods extended by wheat flour were shown excellent results. 3. Among 10% and 20% extensions of urea-melamine copolymer resin, the best results were shown by poplar leaves powder, wheat powder and wood flour. They had no significant difference statistically. 4. In the case of water soluble phenol formaldehyde resin, although dry shear strength of pine leaves powder was higher than that of wheat flour in the ratio of 10%, there was no significant difference between them in the ratio of 10 and 20%. 5. Among 20, 30 and 50% extensions of water soluble phenol formaldehyde resin, wet shear strength of wood flour and bark powder was higher than that of wheat flour. Wet shear strength of wood flour in the ratio of 10% was shown the same tendency as above.

• Journal of Distribution Science
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• v.10 no.2
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• pp.29-41
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• 2012

This paper undertakes a conceptual review of transaction cost to broaden the understanding of the transaction cost analysis (TCA) approach. More than 40 years have passed since Coase's fundamental insight that transaction, coordination, and contracting costs must be considered explicitly in explaining the extent of vertical integration. Coase (1937) forced economists to identify previously neglected constraints on the trading process to foster efficient intrafirm, rather than interfirm, transactions. The transaction cost approach to economic organization study regards transactions as the basic units of analysis and holds that understanding transaction cost economy is central to organizational study. The approach applies to determining efficient boundaries, as between firms and markets, and to internal transaction organization, including employment relations design. TCA, developed principally by Oliver Williamson (1975,1979,1981a) blends institutional economics, organizational theory, and contract law. Further progress in transaction costs research awaits the identification of critical dimensions in which transaction costs differ and an examination of the economizing properties of alternative institutional modes for organizing transactions. The crucial investment distinction is: To what degree are transaction-specific (non-marketable) expenses incurred? Unspecialized items pose few hazards, since buyers can turn toalternative sources, and suppliers can sell output intended for one order to other buyers. Non-marketability problems arise when specific parties' identities have important cost-bearing consequences. Transactions of this kind are labeled idiosyncratic. The summarized results of the review are as follows. First, firms' distribution decisions often prompt examination of the make-or-buy question: Should a marketing activity be performed within the organization by company employees or contracted to an external agent? Second, manufacturers introducing an industrial product to a foreign market face a difficult decision. Should the product be marketed primarily by captive agents (the company sales force and distribution division) or independent intermediaries (outside sales agents and distribution)? Third, the authors develop a theoretical extension to the basic transaction cost model by combining insights from various theories with the TCA approach. Fourth, other such extensions are likely required for the general model to be applied to different channel situations. It is naive to assume the basic model appliesacross markedly different channel contexts without modifications and extensions. Although this study contributes to scholastic research, it is limited by several factors. First, the theoretical perspective of TCA has attracted considerable recent interest in the area of marketing channels. The analysis aims to match the properties of efficient governance structures with the attributes of the transaction. Second, empirical evidence about TCA's basic propositions is sketchy. Apart from Anderson's (1985) study of the vertical integration of the selling function and John's (1984) study of opportunism by franchised dealers, virtually no marketing studies involving the constructs implicated in the analysis have been reported. We hope, therefore, that further research will clarify distinctions between the different aspects of specific assets. Another important line of future research is the integration of efficiency-oriented TCA with organizational approaches that emphasize specific assets' conceptual definition and industry structure. Finally, research of transaction costs, uncertainty, opportunism, and switching costs is critical to future study.

• The Journal of the Korea Contents Association
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• v.14 no.4
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• pp.37-46
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• 2014

Industrialization and urbanization have led automobiles to transform into more than just modes of transportation; they have become daily necessities as well as extensions of living spaces where a variety of activities can be done and automotive applications of the latest information technology are accelerated. Though material abundance has increased in the modern society, the conflicts and the stress emerging from a social structure focused on competition have increased as well. Such lifestyles generate a need for personal space and media content for healing the body and the mind. This research explores the automotive application of video content with the goal of refreshing the minds of the passengers. To this end, previous studies have investigated the emotional effect of videos, focusing on the responses of diverse groups of adults (age group of 20 to 60) who frequently used automobiles, which had video displays installed in them. The results showed that watching video contents on a full window inside a car influenced the creation of positive feelings7 and emotional satisfaction. The research attempts to study the methods of providing video contents and the effects of watching them that could aid the emotional well-being of passengers, and presents the possibility of emotional satisfaction created by a convergence of cars and multimedia contents in the future.

• The Journal of Fisheries Business Administration
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• v.24 no.1
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• pp.65-86
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• 1993

In this paper, fishery economics is reviewed to extend a basic opportunity for developing new fishery economics and to evaluate the effects of the import liberalization on the fish trade structure of Korea. The principle outline of extensions emphasis to realize the modern fishery problems based on fishery economics and develop the practical methodology in order to analyze the impacts of the import liberalization on the fishery and fishermen welfare. During the process of export - oriented industrilization, the role and position of fishery in the economy is changed dynamically. When faced with the imperative of the role and position of fishery in the economy, fishery economists and domestic policy makers must decide how to organize themselves for solving fishery problems under the new regime in the import liberalization on the fish trade. Fishery problems impacted by the new regime can not be solved by fishery itself but be solved by the centralized efforts of all contributors in national views. Therefore the new systematic analytical methodology must be develop and the traditional fishery economics must be related to the regional development strategy and fishery sociology as subsidiary theories specialized. Due to the impacts of the import liberalization on the fish trade structure, fishery economists face with radical changes in the domestic fishery : a place of the resources harvest to place of the combination resource harvest and its demand, a fishing as a resource exploitation to a fishing as a resource management, a traditional small scale costal fishing to a modernized and scaled fishing, fishery using the given natural resource itself to fishery as technology intensive industry, and a food supply industry to a welfare indusry based on the regional and economic resource and social environment. As these changes, fishery and its community's regional and economic resource and social environments as multiple roles of the regional economic development are emphasized in fishery economics under the new regime in the import liberalization on the fish trade. Furthermore, domestic policy makers and administrators in a public sector must realize the above radical changing trends in fishery and understand a social and economic environment in fishery and develop a new fishery structure focusing on the fishing system and the fishery laws. As this point, they make efforts to improve and develop fishery as a food supply industry. Japan, for example, has a non - governmental organization to conflict the problem of international fishery such as a movement of a civil environmental protection. Also fishermen in Japan already realized conservation and pollution problems in fishing as fundamental issues of human being.

• Journal of the Institute of Electronics and Information Engineers
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• v.53 no.8
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• pp.85-92
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• 2016

Mobile cloud computing (MCC) is not just extensions of cloud concepts into mobile environments, but the service technologies that all mobile devices including smartphone can use the desired services by using cloud technology without the constraints of time and space. Currently, a lot of works on mobile cloud computing have been actively researching, whereas user interfaces are not so much researched. The main features and contributions of this paper are as follows. First, develop UI considering UX that is different from conventional interfaces supported by SPICE. Second, combine two button interface into one button interface when keyboard is used in mobile cloud computing clients. Third, develop a mouse interface suitable for mobile cloud computing clients. Fourth, in mobile cloud computing client, solve a problem that the selection of button/files/folder has at the corner. Finally, in mobile cloud computing clients we change mouse scroll mapping functions from volume button to scroll interface in touch-screen. The results of performance evaluation shows that users can input easily with the increased and fixed mouse interface. Since shortcut keys instead of the complex button keys of keyboard are provided, the input with 3-6 steps is reduced into 1 step, which can simply support complex keys and mouse input for users.

• Journal of Internet Computing and Services
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• v.16 no.3
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• pp.21-32
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• 2015

Since spatio-temporal local features for video representation have become an important issue of modeless bottom-up approaches in action recognition, various methods for feature extraction and description have been proposed in many papers. In particular, BoF(bag of features) has been promised coherent recognition results. The most important part for BoF is how to represent dynamic information of actions in videos. Most of existing BoF methods consider the video as a spatio-temporal volume and describe neighboring 3D interest points as complex volumetric patches. To simplify these complex 3D methods, this paper proposes a novel method that builds BoF representation as a way to learn 2D interest points directly from video data. The basic idea of proposed method is to gather feature points not only from 2D xy spatial planes of traditional frames, but from the 2D time axis called spatio-temporal frame as well. Such spatial-temporal features are able to capture dynamic information from the action videos and are well-suited to recognize human actions without need of 3D extensions for the feature descriptors. The spatio-temporal BoF approach using SIFT and SURF feature descriptors obtains good recognition rates on a well-known actions recognition dataset. Compared with more sophisticated scheme of 3D based HoG/HoF descriptors, proposed method is easier to compute and simpler to understand.

• Journal of Life Science
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• v.28 no.9
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• pp.1068-1075
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• 2018

Kaempferia parviflora, an herbaceous plant in the family Zingiberaceae, is popular in many tropical regions. It is called as black ginger or krachaidum in Thailand and Laos, and its raw or dried root have been used as spices and teas. The rhizomes also have been traditionally used to treat gastrointestinal disorders, ulcers, gout, dysentery, allergies and to improve physical work capacity. Recently, its anti-obesity, anti-oxidant, anti-inflammatory and blood clot-lysis activities were reported. In this study, the anti-thrombosis activity of black ginger was investigated, since improvement in blood fluidity leads to the prevention of various lifestyle-related diseases. The hot water and ethanol extract and their subsequent solvent fractions (hexane, ethylacetate, butanol fractions and water residue) were prepared, and their anti-coagulation and platelet aggregation inhibitory activities were determined, respectively. Among the black ginger extracts and their fractions, the ethylacetate fraction (EAF) of ethanol extract only showed significant extensions of blood coagulation time determined by thrombin time (TT), prothrombin time (PT), and activated partial thromboplastin time (aPTT). At 5 mg/ml concentration, TT, PT and aPTT were extended to 1.22, 1.49 and >15-folds compared to non-treatment. The EAFs of ethanol and hot water extract showed strong inhibitions against collagen-induced platelet aggregations, which are comparable to inhibitions of aspirin. Also the EAFs from black ginger did not show any hemolysis activity against human RBC up to 0.5 mg/ml. Our results suggest that the EAF of black ginger has a potential as novel anti-coagulation and ant-platelet aggregation agent. This report provides the first evidence of anti-coagulation activity of black ginger.

• Journal of the Korea Concrete Institute
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• v.18 no.1 s.91
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• pp.47-56
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• 2006

The repeated loading responses of four shear-critical reinforced concrete beams with two different shear span-to-depth ratios, were studied. One series of beams was reinforced using pairs of bundled stirrups with $90^{\circ}$ standard hooks, haying free end extensions of $6d_b$. The companion beams contained shear reinforcement made with larger diameter headed bars anchored with 50mm diameter circular heads. A single headed bar had the same area as a pair of bundled stirrups and hence the two series were comparable. The test results indicate that beams containing headed bar stirrups have a superior performance to companion beams containing bundled standard stirrups with improved ductility, larger energy absorption and enhanced post-peak load carrying capability. Due to splitting of the concrete cover and local crushing, the hooks of the standard stirrups opened resulting in loss of anchorage. In contrast, the headed bar stirrups did not lose their anchorage and hence were able to develop strain hardening and also served to delay buckling of the flexural compression steel. Excellent load-deflection predictions were obtained by reducing the tension stiffening to account for repeated load effects.

• Magazine of the Korea Concrete Institute
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• v.11 no.2
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• pp.187-196
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• 1999

An experimental investigation was conducted to study the structural behavior of concrete columns confined with welded grids. The full-scale columns with different volumetric ratio, spacing and arrangement of welded reinforcement grids were tested under simulated seismic loading. The columns were subjected to constant axial compression of approximately 20% or 40% of their capacities accompanied by incrementally increasing lateral deformation reversals. The results indicate that the welded reinforcement grid can be used effectively as confinement reinforcement provided that the steel used, have sufficient ductility and the welding process employed does not alter the strength and elongation characteristics of steel. The grids improved the structural performance of columns, which developed lateral drift ratios in excess of 3% with the spacing and volumetric ratio of transverse reinforcement similar to those required by the ACI 318-95 Building Code. Drift capacity further increased when grids with larger number of cells were used. Furthermore, the use of grids reduced congesting of reinforcement while the dimensional accuracy provided perfect support to longitudinal reinforcement.