• JSTS:Journal of Semiconductor Technology and Science
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• v.3 no.3
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• pp.107-113
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• 2003

Microelectronics device performance and its reliability are directly related to and controlled by its constituent materials and their microstructure. Specific processes used to form and shape the materials microstructure need to be controlled in order to achieve the ultimate device performance. Examples of front-end and back-end ULSI processes, packaging process, and novel optical storage materials are given to illustrate such process-structure-property-reliability relationship. As more novel materials are introduced to meet the new requirements for device shrinkage, such under-standing is indispensable for future generation process development and reliability assessment.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.34 no.5
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• pp.70-76
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• 2002

Ten years ago most papermakers were convinced that a system needs to be voluminous and heavy for controllability and stability. In order to improve grade changing dynamics, the author of this paper began developing a compact papermachine wet end. The results have proven that compactness is beneficial even more broadly. Quoting Voith$^1$the trend is now the opposite - the systematic collecting and direct feeding of the individual water flows back into the system". In its gasless form this is actually covered by a POM Technology Patent.tent.

• Transactions of the Korean Society of Automotive Engineers
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• v.18 no.5
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• pp.20-24
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• 2010

The position of the automobile's head restraint is very important for the neck injury in rear end collision. This study is about influence of the head restraint height and distance on neck injury during rear end collision. The effects of the position have been evaluated experimentally. The neck injuries are calculated by the relative acceleration between the upper and lower neck. As a result, It is found that the head restraint should be close enough to the back of the head and high enough to the top of the head.

• International Journal of Concrete Structures and Materials
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• v.11 no.1
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• pp.29-43
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• 2017

This study investigates the blast resistance of fiber-reinforced cementitious composite (FRCC) panels, with fiber volume fractions of 2%, subjected to contact explosions using an emulsion explosive. A number of FRCC panels with five different fiber mixtures (i.e., micro polyvinyl alcohol fiber, micro polyethylene fiber, macro hooked-end steel fiber, micro polyvinyl alcohol fiber with macro hooked-end steel fiber, and micro polyethylene fiber with macro hooked-end steel fiber) were fabricated and tested. In addition, the blast resistance of plain panels (i.e., non-fiber-reinforced high strength concrete, and non-fiber-reinforced cementitious composites) were examined for comparison with those of the FRCC panels. The resistance of the panels to spall failure improved with the addition of micro synthetic fibers and/or macro hooked-end steel fibers as compared to those of the plain panels. The fracture energy of the FRCC panels was significantly higher than that of the plain panels, which reduced the local damage experienced by the FRCCs. The cracks on the back side of the micro synthetic fiber-reinforced panel due to contact explosions were greatly controlled compared to the macro hooked-end steel fiber-reinforced panel. However, the blast resistance of the macro hooked-end steel fiber-reinforced panel was improved by hybrid with micro synthetic fibers.

• Physical Therapy Rehabilitation Science
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• v.10 no.2
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• pp.156-160
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• 2021

Objective: Low back pain easily becomes chronic and has a high recurrence rate. Therefore, it is most important to prevent chronicity and reduce the risk of recurrence in the early stages of back pain or at the stage with mild pain. Therefore, this study was conducted to compare hip joint muscle strength, trunk muscle endurance, and pelvic alignment between subjects with mild low back pain and subjects without back pain. Design: Crossed-sectional study Methods: The study was conducted by recruiting 30 students in their twenties who are enrolled in K University in Gyeongsangnam-do, and classifying them into 15 patients with mild back pain and 15 patients with normal. The subjects who participated in the experiment were measured for hip flexor and extensor muscle strength, trunk flexion and extension muscle endurance, and pelvic alignment. To measure hip joint muscle strength, biodex was used, and muscle endurance of the trunk was recorded at the end range of the trunk flexion and extension. And pelvic alignment was measured using Formetric 4D. Results: There were no significant differences in hip joint muscle strength, pelvic alignment, and trunk extension muscle endurance. The retention time was found to be significantly shorter in the mild low back pain group than in the normal group for trunk flexion muscle endurance. Conclusions: In the early stages of back pain or in the mild pain stage, training to increase muscle endurance of the flexor muscles may be helpful.

• Journal of the Korea Society for Simulation
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• v.26 no.2
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• pp.9-17
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• 2017

The problem of social phenomenon is getting more complicated than past decades, and the simulation engineers need more computation power to solve the problem. Therefore, the needs of the computational resources of the modeling and simulation environment are increasing. In the perspective of the simulation, it is necessary to allocate computational resources flexibly so that the simulation can be performed per the available budget range. As an alternative to the simulation environment to accommodate these requirements, cloud service has emerged as an environment in which computing resources can be used flexibly. This paper proposes a web-based simulation framework which consists of a front-end that reconstructs the simulation model using the web, and a back-end that executes the discrete event simulation. This paper also carried out a case study which shows web-based simulation framework has better overall runtime than standalone simulation framework.

• Journal of the Korea Society of Computer and Information
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• v.16 no.3
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• pp.229-236
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• 2011

In this paper we present light weighted English-to-Korean and Korean-to-English mobile translators on smart phones. For natural translation and higher translation quality, translation engines are hybridized with Translation Memory (TM) and Rule-based translation engine. In order to maximize the usability of the system, we combined an Optical Character Recognition (OCR) engine and Text-to-Speech (TTS) engine as a Front-End and Back-end of the mobile translators. With the BLEU and NIST evaluation metrics, the experimental results show our E-K and K-E mobile translation equality reach 72.4% and 77.7% of Google translators, respectively. This shows the quality of our mobile translators almost reaches the that of server-based machine translation to show its commercial usefulness.

• Journal of the Korea Society of Computer and Information
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• v.15 no.9
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• pp.129-136
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• 2010

With mobile computing, wireless sensor network and sensor technologies, ubiquitous computing services are being realized and could satisfy the feasibility of ubiquitous healthcare to everyone. This u-Healthcare service can improve life quality of human since medical service can be provided to anyone, anytime, and anywhere. To confirm the vision of u-Healthcare service, we've implemented a healthcare system for heart disease patient which is composed of two components. Front-end collects various signals such as temperature, blood pressure, SpO2, and electrocardiogram, etc. As a backend, medical information server accumulates sensing data and performs back-end processing. To simply transfer these sensing values to a medical team may be too trivial. So, we've designed a model based on context awareness for more improved medical service which is based on artificial neural network. Through rigid experiments, we could confirm that the proposed system can provide improved medical service.

• Journal of the Korean Geosynthetics Society
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• v.21 no.3
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• pp.49-59
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• 2022

This study was conducted to find out the rational and appropriate design of drilled shaft. In other words, in order to find out the variation of ultimate bearing capacity according to the change in the support layer of drilled shaft, back analysis was performed using the bi-directional pile load test performed on drilled shaft. Based on the back-analyzed data, numerical analysis of the pile head load was performed, and the ultimate bearing capacity in the target ground was evaluated using the Davisson method. As a result of numerical analysis of one case where the end of the pile was seated on the top of the weathered rock layer, and three cases where the end of the pile was embedded at different locations in the weathered soil, it was found that sufficient ultimate bearing capacity was secured in all cases. In other words, the case where the end of the pile is seated on the top of the weathered rock layer, not embedded the weathered rock, and the drilled shaft embedded into the weathered soil also have sufficient bearing capacity, so it can be used as a support layer for drilled shaft.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.5
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• pp.2499-2522
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• 2017

Multi-hop networks are a low-setup-cost solution for enlarging an area of network coverage through multi-hop routing. Carrier sense multiple access with collision avoidance (CSMA/CA) is frequently used in multi-hop networks. Multi-hop networks face multiple problems, such as a rise in contention for the medium, and packet loss under heavy-load, saturated conditions, which consumes more bandwidth due to re-transmissions. The number of re-transmissions carried out in a multi-hop network plays a major role in the achievable quality of service (QoS). This paper presents a statistical, analytical model for the end-to-end delay of contention-based medium access control (MAC) strategies. These strategies schedule a packet before performing the back-off contention for both differentiated heterogeneous data and homogeneous data under saturation conditions. The analytical model is an application of Markov chain theory and queuing theory. The M/M/1 model is used to derive access queue waiting times, and an absorbing Markov chain is used to determine the expected number of re-transmissions in a multi-hop scenario. This is then used to calculate the expected end-to-end delay. The prediction by the proposed model is compared to the simulation results, and shows close correlation for the different test cases with different arrival rates.