• KSII Transactions on Internet and Information Systems (TIIS)
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• v.17 no.7
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• pp.1935-1950
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• 2023

The arrival of the Internet of Things and 5G technology enables users to rely on edge computing platforms to process massive data. Data sharing based on edge computing refines the efficiency of data collection and analysis, saves the communication cost of data transmission back and forth, but also causes the privacy leakage of a lot of user data. Based on attribute-based encryption and blockchain technology, we design a fine-grained access control scheme for data in edge computing, which has the characteristics of verifiability, support for outsourcing decryption and user attribute revocation. User attributes are authorized by multi-attribute authorization, and the calculation of outsourcing decryption in attribute encryption is completed by edge server, which reduces the computing cost of end users. Meanwhile, We implemented the user's attribute revocation process through the dual encryption process of attribute authority and blockchain. Compared with other schemes, our scheme can manage users' attributes more flexibly. Blockchain technology also ensures the verifiability in the process of outsourcing decryption, which reduces the space occupied by ciphertext compared with other schemes. Meanwhile, the user attribute revocation scheme realizes the dynamic management of user attribute and protects the privacy of user attribute.

• Nuclear Engineering and Technology
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• v.56 no.4
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• pp.1385-1397
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• 2024

Bentonite is a recommended material for the multiple barriers in the final disposal of low-level radioactive waste (LLW) to prevent groundwater intrusion and nuclear species migration. However, after drying-wetting cycling during the repository construction stage and ion exchange with the concrete barrier in the long-term repository, the bentonite mechanical behaviors, including swelling capacity and hydraulic conductivity, would be further influenced by the groundwater intrusion, resulting in radioactive leakage. To comprehensively examine the factors on the mechanical characteristics of bentonite, this study presented scenarios involving MX-80 and KV-1 bentonites subjected to drying-wetting cycling and accelerated ion migration. The experiments subsequently measured free swelling, swelling pressure, and hydraulic conductivity of bentonites with intrusions of seawater, high pH, and low pH solutions. The results indicated that the solutions caused a reduction in swelling volume and pressure, and an increase in hydraulic conductivity. Specifically, the swelling capability of bentonite with drying-wetting cycling in the seawater decreased significantly by 60%, while hydraulic conductivity increased by more than three times. Therefore, the study suggested minimizing drying-wetting cycling and preventing seawater intrusion, ensuring a long service life of the multiple barriers in the LLW repository.

• Computers and Concrete
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• v.34 no.4
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• pp.427-446
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• 2024

The I-shaped steel reinforced recycled aggregate concrete (SRRC) composite structure has the advantages of high bearing capacity and environmental protection, and the interfacial bond strength is an important theory. To this end, the I-shaped SRRC bond strength and its calculation based on artificial neural network (ANN) will be studied. Firstly, 39 push out tests of I-shaped SRRC were conducted, the load-slip curve has obvious regularity, which is divided into 4 segments by 3 regular points. Three bond strengths were defined based on these three rule points, and the approximate ranges of their values and the laws of influence of each factor on them were found. Secondly, the Elman ANN model used for the prediction of bond strength was established, and the parameters of Elman ANN predicting I-shaped SRRC bond strength were studied, and the effects of detailed parameters on the prediction results were revealed. Finally, the bond strength of SRRC was predicted using Elman and BP (back propagation) neural network models, both of which showed good prediction results. This study is a theoretical basis for the design and fine simulation of I-shaped SRRC composite structures.

• Journal of Biosystems Engineering
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• v.33 no.1
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• pp.38-44
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• 2008

The freight vehicle is mostly used to transport the fruit. Shock and impact generated by the freight vehicle may give serious damage to fruits hence to reduce the fruits damage, the optimum packaging design during transportation by vehicle is required. In order to design the packaging system for fruit transportation optimally, the comprehension of characteristic for vibration and shock acting on vehicles under various road conditions and loading methods is required. This research was performed to analyze the shock characteristics, acceleration level and power spectral density (PSD) of the fruit transportation vehicles under several travel roads and positions. The vibration signal was measured and analyzed at the transportation vehicle operating on the road of three different surface conditions. The maximum acceleration was measured at the rear-end of the vehicle, and the acceleration in the direction of up-and-down (z-axis) was much greater than those in the directions of back-and-forth (x-axis) or right-and-left (y-axis). The peak acceleration in the direction of up-and-down (z-axis) at the vehicle driving on the expressway, the local road paved with concrete, and unpaved local road were 5.3621 G, 8.232 G, and 14.162 G respectively. PSD at 2.44 Hz showed maximum value at all road conditions. The maximum values of PSD on the expressway, a local road paved with concrete, and unpaved local road were 0.0075222 $G^2/Hz$, 0.058655 $G^2/Hz$, and 0.24598 $G^2/Hz$ respectively. The value of PSD decreased with an increase of the vibration frequency of the transportation vehicle. In most cases, the vibration frequency was below 20 Hz during transportation.

• Journal of the Korean Society of Clothing and Textiles
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• v.36 no.11
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• pp.1197-1207
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• 2012

This study provides information for the design of pediatric inpatient uniforms with functionality and aesthetic beauty through a questionnaire-survey of the conditions of providing, wearing, preferences and improvement requirements for pediatric inpatient uniforms. As a result of the survey, intravenous injections were mostly given on the back of the hand, and the method of changing uniforms after intravenous injections was (in most cases) to pass the injection bottle through a sleeve or pant leg while the needle is inserted. The respondents answered that the sleeve length and pant length did not match. As a result of the preference of the pediatric inpatient design survey, respondents indicated they preferred pajama type, yellow color and medium size animal patterns. A similar ratio of set-in and raglan with no collar but with 3/4 length sleeve of round neck, front end, sleeve top opening, button closing and two pockets were preferred for shirts; however, a 3/4 length with rubber string on the waist, no opening and inner opening were preferred at the same ratio for pants. As for the method to adjust the length to assign functionality to pediatric inpatient uniforms, the most preferred sleeve was a roll-up sleeve with a strap and the most preferred pants were length adjusted pants that used a strap for both shirts and pants with a both sides strap. In addition, the majority of the respondents answered that a hand wrapper that protects the injection location during intravenous injections needs be developed. As for the development type, a half glove type and glove type were preferred in sequential order.

• Journal of Convergence for Information Technology
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• v.9 no.12
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• pp.39-46
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• 2019

The competition for standardization in the enterprise environment starts with the data tier of the back-end and the standard enterprise middle tier is being stabilized by standardization as it is accepted as the Spring Framework. In addition, with the advent of new devices in an increasingly rapid cycle, securing compatibility with web and mobile services has become an important competitive advantage for web service companies. However, companies are unable to secure competent technical personnel appropriate for the rapidly changing environment of the information generation, and the curriculum of educational universities does not reflect the demand of new competency-oriented curriculum. Therefore, in this study, in order to acquire competency-oriented skills required for such an enterprise system platform environment and to develop a curriculum, the system using Spring Data JPA in the Spring Framework environment was implemented through documenting for each analysis and design step. It aims to provide a reference model for the full stack competency-based curriculum and capstone design curriculum that can be applied immediately in the enterprise environment.

• The korean journal of orthodontics
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• v.25 no.1 s.48
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• pp.73-85
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• 1995

Multi-Vertical Loop Arch Wire(MVLAW) is a kind of appliance for uprighting the mesially inclined posterior teeth axes simultaneously. In this study MVLAW was classified as 3 types by modifing the vertical loop design and named type A, B and C. Each MVLAW was fabricated from .017'x.025' TMA wire and preactivated at the distal end of the open vertical loop with 10 degree tip-back bend(type B has an electric welding stop at the distal end of each loop and type C has no electric welding stop). Type A MVLAW was preactivated at the apex of each open vertical loop with 10 degree tip-back bend(the electric welding stop of type A is positionod at the mesial side of each loop). The aim of the present study was to identify when and which MVLAW is more effective to correct the buccal segment axes simultaneously. The Photoelastic overview of the upper and lower right quadrant showed that stress concentrations were observed in its photoelastic model. The obtained results were as follows : 1. Higher level compression can be seen clearly at the distal curvature of the lower 1st and 2nd molar when A type MVLAW was applied without short class m elastic, but mild compression cannot be seen at the distal curvature of lower anterior teeth using the class m elastic. 2. Higher concentration was presented at the mesial curvature from the lower 1st premolar to the 2nd molar than the anterior teeth when B type MVLAW without short class III elastic was applied, but using the short class III elastic, higher concentration of compression was presented in the anterior teeth area. 3. Areas of higher compression and tension were not observed at the mesial and distal curvature of the entire 1ower teeth except lower central and lateral incisors in C type MVLAW without short class III elastic, but using the short class III elastic, higher concentration was seen at the mesial curvature of the lower 1st premolar and 1ower anterior teeth.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.05a
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• pp.70-73
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• 2012

In this paper, we introduce a design method for a quasi-Yagi antenna (QYA) with broadband characteristics of an impedance bandwidth ratio of > 2 : 1 and a gain of > 4 dBi. The QYA is fed by a microstrip line fabricated on a coplanar strip line and it consists of 3 elements; a planar dipole, a nearby director close to the dipole, and a ground plane reflector. By placing a rectangular patch-type director with large width near to the dipole driver, broadband characteristics are achieved. An optimized 3-element QYA for operation over 1.6-3.5 GHz (bandwidth ratio 2.2 : 1) is fabricated on an FR4 substrate with a size of $90mm{\times}90mm$ and tested experimentally. The results show an impedance bandwidth of 1.56-3.74 GHz (bandwidth ratio 2.4 : 1) for VSWR < 2, a peak gain of 4.41-6.53 dBi, and a front-to-back ratio (FBR) > 13.6 dB within the bandwidth.

• Korean Institute of Interior Design Journal
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• v.17 no.1
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• pp.3-10
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• 2008

This study is concerned with the process of development and architectural characteristics of secular stained glass in the 20th century. Stained glass had been architectural art from the origin. But it had declined since the Renaissance era, and began to revive in the early 20th century. Stained glass work is very flourish in Korea today, but it is still treated as simple decoration or 2-dimensional mosaic. Architect and interior designer even have little understanding of architectural character of stained glass. In order to recover the architectural nature of stained glass, I have considered the process of development of secular stained glass in the 20th century, and analysed the works of Frank Lloyd Wright, the postwar German artists, Georg Meistermann, Ludwig Schaffrath, Johannes Schreiter, and English artist, Brian Clarke. Major findings of the study are as followings : First, stained glass has come to life again from the secular glass painting decoration in the end of the 19th century, through Art-Nouveau, De Stil, Bauhaus in the beginning of the 20th century, and L'Art $Sacr\acute{e}$. Second, Frank Lloyd Wright, the postwar German artists and Brian Clarke have established the architectural concept and potentiality of the modem stained glass in the secular field. Third, They have done by coming back to the basic creative method by traditional lead-came technique in spite of the development of various materials and techniques. Forth, stained glass fundamentally has architectural characteristics as the characters of Space, Time, Place, Context, and they have showed the new possibility of stained glass by recovery of these characters.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.20 no.12
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• pp.2199-2205
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• 2016

In this paper, a design method for a coplanar waveguide (CPW)-fed 2-element quasi-Yagi antenna (QYA) is studied. A balun between CPW and coplanar strip (CPS) which feeds a planar dipole is implemented by connecting the one end of ground strips in a CPW to a signal strip. The antenna size is reduced by bent strip dipole and reflector, and an integrated balun. The proposed antenna was designed for the operation in a UHF radio frequency identification (RFID) band of 902-928 MHz, and the effects of various parameters such as dipole length, reflector length, distance between dipole and reflector, feed position were examined. The antenna with a size of $90mm{\times}80mm$ was fabricated on an FR4 substrate, and the experiment results reveal a frequency band of 885-942 MHz for a voltage standing wave ratio < 2, a gain > 4.3 dBi, and a front-to-back ratio > 7 dB over the frequency band for the UHF RFID.