• Journal of the Korea Society of Computer and Information
• /
• v.13 no.5
• /
• pp.117-124
• /
• 2008

It improves human being's life quality that all people can have mure convenient medical service under pervasive computing environment. For a pervasive health care application for cardiac patient, we've implemented a health care system, which is composed of three parts. Various sensors monitor outer as well as inner environment of human such as temperature, humidity, light and electrocardiogram, etc. These sensors form a network based on Zigbee. And medical information server accumulates sensing values and performs back-end processing. To simply transfer these sensing values to a medical team is a simple level's medical service. So, we've designed a new service model based on back propagation neural network for more improved medical service. Our experiments show that a proposed healthcare system can give high level's medical service because it can recognize human's context more concretely.

• Polymer(Korea)
• /
• v.32 no.5
• /
• pp.415-420
• /
• 2008

The porcine small intestinal submucosa (SIS) without immunorejection responses and hyalunonic acid (HA) can be used as biomaterials. In this study, we tried to design and characterize novel sponge. SIS- HA sponge was prepared by freeze-drying after addition 1wt% HA solution into fabricated SIS sponge. Sponge was crosslinked with 1-ethyl-(3-3-dimethyl aminopropyl) carbodiimide hydrochloride (EDC) solution with 100mM concentration for 24 hrs and lyophilized. SIS-HA sponge was characterized by scanning electron microscopy and fourier transform infrared spectrometer. And water absorption ability of sponge was evaluated. We seeded NIH/3T3 cells in SIS-HA sponge and cellular attachment was assayed by 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltertazolium-bromide (MTT) test. We demonstrated presence of HA in SIS-HA sponge from C-O functional group observed by the FT-IR analysis. Moreover, we confirmed low cytotoxicity and high cell viability of the SIS-HA sponges. Therefore, we could expect that SIS- HA scaffolds are applicable for the tissue regeneration.

• Journal of the Korea Convergence Society
• /
• v.12 no.12
• /
• pp.117-123
• /
• 2021

The purpose of this study is to convergence comparison the ankle joint angle change during walking of college students in their 20s with flat foot according to the heel height of insole shoes. Qualisys Track Manager Software ver. 2.8 (Qalisys Track Manager) was used for 15 college students. Functional shoes with insoles were manufactured, and the heel heights of the shoes were set to 3cm and 7cm. The subjects wore shoes with two high heels and gaited by attaching a reflex marker to the side of the ankle joint. The angle change of the ankle joint was measured in the gait stance phase. The angle of the ankle joint significantly decreased both heel strike, foot flat, midstance, and toe off to the heel height increased when the subjects with flat feet wore insole shoes. Therefore, it is thought that flat feet should wear low shoes when wearing insoles to reduce the fatigue of the soles and to walk comfortably.

• The Journal of the Korea Contents Association
• /
• v.19 no.7
• /
• pp.393-401
• /
• 2019

In this study, based on the general reasoning that the higher the resolution of the HMD, the greater the presence and immersion of the audience and the greater the presence experience, the difference in the presence experience according to the resolution of the virtual reality device is verified empirically Presence effect. To do this, 300 college students were included in the population, and VR simulations of the Oculus store were conducted using HMD and mobile devices with different resolutions (HD, FHD, WQHD) as stimuli. As a result, there was a significant difference in the presence experience of the audience according to the resolution of the mobile device attached to the virtual reality HMD, and the presence effect had a significant influence on the awakening. On the other hand, no significant influence was found in the effect of emotion. Therefore, we can prove a general reasoning hypothesis that the higher the resolution of the virtual reality device, the greater the presence experience of the audience. However, since the confounding effect and the impression are contradictory in the presence effect side, additional experiments research is required.

• Journal of the Korean Geosynthetics Society
• /
• v.17 no.4
• /
• pp.189-197
• /
• 2018

A sprayable waterproofing membrane which has relatively high adhesive property onto concrete enables faster construction with better waterproof performance compared with a conventional sheet membrane. However, the sprayable waterproofing membrane is a recently developed material and its performance and behavior with structures are not sufficiently reported. Therefore, in this study, the shear behavior of sprayable waterproofing membrane was numerically analyzed using the results of previous studies of composite shotcrete with sprayable waterproofing membrane. From the previous study, shear behavior of shotcrete with sprayable waterproofing membrane was different from shotcrete case and there was a limitation to express the behavior of the interface in general shear strength method. Therefore, in this study, the direct shear test was numerically simulated using two contact models, and then the best suitable method to express the shear behavior of the sprayable waterproofing membrane was suggested.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.18 no.4
• /
• pp.16-25
• /
• 2019

Recently, due to labor shortages in rural areas within South Korea, the demand for upland-field machinery is growing. In addition, there is a lack of development of systematic performance testing of upland-field machinery. Thus, this study examined structural safety and drawbar pull based on soil properties, as a first step for systematic performance testing on the test bed. First, the properties of soil samples from 10 spots within the experimental site were examined. Second, the strain was measured and converted into stress on 8 points of an onion harvester that are likely to fail. More specifically, the chosen parts are linked to the power, along with the drawbar pull, using a 6-component load cell equipped between the tractor and the onion harvester. The water content of the soil ranged between 5.7%-7.5%, and the strength between 250-1171 kPa. The test soil was subsequently classified into loam soil based on the size distribution ratio of the sieved soil. The onion harvester can be considered as structurally safe based on the derived safety factor and the drawbar pull of 115-1194 kgf, according to the working speed based on agricultural fieldwork.

• The Journal of the Acoustical Society of Korea
• /
• v.38 no.3
• /
• pp.334-339
• /
• 2019

In this study, the vibration test method to nondestructively evaluate the possibility of vehicle BSR (Buzz, Squeak, Rattle) noise generation in spot-welded structures was proposed. The weld quality was predicted by analyzing the local vibration transmission characteristics for the beam-shaped structure attached to testing spots. The bending stiffness was evaluated from the identified vibration properties. From the change in the stiffness, the weld quality was evaluated. For verification of the proposed method, the welded specimens were fabricated with partial changes in welding parameters. The local vibration transfers were measured. The frequency bands affected by the weld quality was identified. The capability of evaluating the welding parameters including defect position and quality variations was investigated. The proposed method enables fast quality evaluation to minimize the possibility of BSR noise generation in the manufactured vehicle.

• The Journal of Engineering Geology
• /
• v.31 no.3
• /
• pp.321-332
• /
• 2021

Though development of reinforced earth wall is on the rise recently, safety verification for various methods remains behind which has caused the problems including collapse after installation. This study aims to evaluate the field applicability of the shape of flexible strip reinforcement according to pullout resistance test and field damage test. The test specimens were 3 shape of reinforcement, the typical flexible band reinforcement, developed luged band reinforcement, and band type reinforcement made by cutting geogrid. It was found that reinforcement of type have strengths and weaknesses, respectively. The best type of flexible strip reinforcements can be selected, if the conditions are considered with the installation conditions of the reinforcing earth retaining wall and the particle size of the backfill materials.

• Journal of the Korea Institute of Building Construction
• /
• v.20 no.6
• /
• pp.481-488
• /
• 2020

The arc thermal metal spraying method (ATMSM) has been used in Korea to improve the electromagnetic pulse (EMP) shielding effect of building and infrastructure by three machines of MS, KMS and HMS (Metal Spray, Korea Metal Spray, High-frequency Meta Spray). The adhesion ability of sprayed metal was found to be 58.32, 64.66 and 87.62% for MS, KMS and HMS, respectively. The metal sprayed area per hour of MS, KMS and HMS was calculated and found to be 14.3, 19.25 and 22.16㎡/h, respectively. The HMS showed the highest metal spray area attributed to the diameter of metal wire i.e. 1.6mm which sprayed 80 mm with 18 m/min. There was minimum loss of metal and the highest efficiency by HMS compared to others. Therefore, it is suggested to use HMS for metal spraying by ATMSM to enhance the EMP shielding effect.

• Journal of Platform Technology
• /
• v.8 no.4
• /
• pp.20-28
• /
• 2020

In this paper, a voice, object, and optical character recognition platform including voice recognition-based smart wearable devices, smart devices, and web AI servers was proposed as an appropriate technology to help the visually impaired to live independently by learning the life cycle of the visually impaired in advance. The wearable device for the visually impaired was designed and manufactured with a reverse neckband structure to increase the convenience of wearing and the efficiency of object recognition. And the high-sensitivity small microphone and speaker attached to the wearable device was configured to support the voice recognition interface function consisting of the app of the smart device linked to the wearable device. From experimental results, the voice, object, and optical character recognition service used open source and Google APIs in the web AI server, and it was confirmed that the accuracy of voice, object and optical character recognition of the service platform achieved an average of 90% or more.