• TTA Journal
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• s.109
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• pp.123-126
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• 2007

IPTV 기술의 국제표준화 추진을 위해 ITU-T의 FG(포커스그룹) IPTV 제3차 회의가 2007년 1월 22일부터 26일까지 미국 캘리포니아 마운틴뷰에서 개최되었다. 본 원고는 제3차 FG IPTV의 주요 결과를 요약, 정리한 것이다.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.37 no.1
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• pp.9-17
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• 2001

To improve the fishing environment of Alaska pollack fishing ground of the East coast in Korea, lost fishing gear were recovered from June to July 1998, May 1999 and from July to August 1999 in the sea near Goseong, Gangwon province. The lost fishing gear was recovered by grapnel. As the results, the lost fishing gear, which was consist of gill nets and traps, was produced from fishing activities, whereas most of them was the bottom gill nets. The weight of lost fishing gears was gill nets of 1,170 t and traps off 4t. The recovered gill nets decreased 12.02 t per mile from 22.74 t, in 1998 to 10.72 t, in 1999. Recovery rate of lost fishing gear was low as 38% in 1998, 41.9% in 1999 and CPUE was 11.27 t/trial in 1998, 7.48 t/trial in 1999. The recovery of lost fishing gear in fishing ground by using grapnel was considered as a useful method.

• Journal of the Korean Wood Science and Technology
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• v.18 no.1
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• pp.39-51
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• 1990

This research was carried out to offer the basis data for development of optimum drying schedule for a domestic oak species (Quercus grosseserrata B1.) by investigating drying rate. stress, defect, and moisuture gradient with board thicknesses and drying schedules (code number T4-C2 and T3-B1). The results were obtained as follows: 1. Average drying rate and total drying time from 52.2% to 5.8% were 0.105%/hr and 486 hours for drying schedule T4-C2 and those from 62.1% to 8.3% were 0.070%/hr. and 811 hours for drying schedule T3-B1. 2. Drying rates for 28mm- and 31mm-thick boards showed similar tendency, but were significantly different from 25mm- thick board in drying schedule T4-C2 and those for 22mm-, 25mm- 28mm- and 31mm-thick boards showed similar tendency but were significantly different from 19mm- thick boards in drying schedule T3-B1. 3. The moisture gradients for drying schedule T4-C2 were steeper than those for drying schedule T3-B1 during drying period. and especially in early drying stage slow slope of moisture gradients of drying schedule T3-B1 was effective in preventing serious problem of surface checks. 4. Drying stresses were lower in drying schedule T3-B1 than in drying schedule T4-C2 during drying period. 5. Drying schedule T4-C2 was appropriate for 25mm-thick board but not for 28mm- and 31mm-thick board because of strong drying condition. Drying schedule T3-B1 was appropriate for 28mm- and 31 mm-thick board but not for 19mm-, 22mm-, and 25mm-thick board because of weak drying condition.

• The Journal of the Korea Contents Association
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• v.19 no.11
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• pp.71-79
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• 2019

This study was conducted to examine the awareness and demands of parents and teachers on the use of IoT healthcare devices at daycare centers. A survey was conducted on 200 teachers and 200 parents. Collected data were analyzed by Frequency analysis, t-test, 𝑥2, using the SPSS WIN 22.0. The results of this study are as follows. First, teachers showed a higher level of preference for using IoT healthcare devices as they showed positive perception and support compared to parents, and showed higher recognition of information leakage than parents. Second, teachers and parents were most hoping to use IoT healthcare devices at emergency response in daycare-centers and had the highest demands for wearable devices. As a result of the both parents and teachers demand cost-sharing. Based on the results of this study, the possibility of utilizing IoT healthcare devices in daycare centers were discussed.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.22 no.6
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• pp.7-12
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• 2022

This paper introduces the implementation of the AWS IoT service and MQTT based smart home system. The smart home system implemented in this study can monitor temperature and humidity, and can manually adjust the air conditioner heating, and can check the visitors with the camera and remotely control the door lock. The implemented smart home system controls door locks, heating and air conditioners using Arduino, and manages the collected data and control information using the AWS IoT service. In this study, the Android app has been developed to allow users to control IoT devices remotely, and the MQTT protocol was used for data communication and control between the app and the AWS IoT server and Arduino. The implemented smart home system has been implemented based on AWS IoT service, which has scalability to add sensors and devices.

• Journal of the Korea Society of Computer and Information
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• v.22 no.9
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• pp.107-113
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• 2017

In this paper, we propose a medication reminder system using IoT platforms and products to help old adults keep track of their medication schedule, one of 10 Korean instrumental activities in daily living (K-IADL). An interworking architecture based on the oneM2M standard platform is designed to allow various IoT products to be connected each other through interworking proxy entities. A prototype system for the medication reminder service is developed, which consists of a pair of off-the-shelf pill bottle and container box embedded with an NFC tag and reader respectively, three types of actuators including a LIFX LED lightbulb, Musaic speaker, Microsoft Band 2, and smartphone applications. The experiment shows that our medication reminder system can make alarms for old adults to take their pills appropriately considering where they are and when they have food inferred from data collected from sensors including ultrasonic sensor and rice cooker, fostering them to keep their medication routine.

• Journal of Sensor Science and Technology
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• v.22 no.3
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• pp.185-190
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• 2013

We report on direct finding of how the morphology (i.e. filopodia width) of $CD4^+$ T lymphocytes correlates with the size of the quartz nanohohole arrays (QNHAs, 140, 200, 270, and 550 nm in diameter) via scanning electron microscopy (SEM). This research exhibits that the filopodia of $CD4^+$ T-lymphocytes extended on the QNHA substrates were observed to increase in width by increasing the size of QNHA in diameter from 140 to 550 nm. This strong linear response ($R^2$=0.988, n = 6) in filopodia's width of surface-bound $CD4^+$ T-cells with topographical structures of QNHA can be explained by contact guidance between the cells and solid-state substrates. Furthermore, this research suggests that the protruded filopodia of surface-bound T-lymphocytes can be used as a biosensor for sensing the topographical information of the nano-patterned substrates.

• Journal of Environmental Science International
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• v.22 no.3
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• pp.379-383
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• 2013

This study was conducted to investigate the changes in nitrogen and soluble reactive phosphorus(SRP) contents from hanwoo manure using probiotics to feed and manure additives during 5 weeks. A total of 45 hanwoo(24 months old) with averaging $580{\pm}20$ kg in weight were randomly assigned to 3 dietary treatments with 3 replicates per treatment(5 hanwoo per pen, $5{\times}8m$). The treatment were supplemented, control, T1(10 kg roughage + 2 kg concentrate(2% probiotics as-fed basis)), and T2(10 kg roughage + 2 kg concentrate(2% probiotics as-fed basis) + 7 kg probiotics on the surface of hanwoo manure (top-dressing)). During the experimental period, there were statistically significant differences(P<0.05) in pH values at 3 and 5 weeks; TN contents at 5 weeks; and SRP contents at 5 weeks in all treatments. Adding probiotics to feed or feed and manure increased manure pH in comparison with controls. As time increased, changes in TN contents decreased in the order: T2 > Control > T1. Especially, the reduction in SRP contents in all treatments at 5 weeks was in following order: T1 > T2 > Control. This result suggests that it is possible to make efficient use of probiotics as feed and manure additives for reducing environmental pollution or to provide fundamental information on livestock managements to producers.

• Journal of the Korean institute of surface engineering
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• v.51 no.6
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• pp.354-359
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• 2018

NaCl-induced hot corrosion behavior of ASTM T22 (Fe-2.25Cr-1Mo), T91 (Fe-9Cr-1Mo), T92 (Fe-9Cr-1.8W-0.5Mo), 347HFG (Fe-18-Cr-11Ni), and 310H (Fe-25Cr-19Ni) steels was studied after spraying NaCl on the surface. During corrosion at $600-800^{\circ}C$ for 50-100 h, thick, non-adherent, fragile, somewhat porous oxide scales formed. All the alloys corroded fast with large weight gains owing to fast scaling and destruction of protective oxide scales. Corrosion rates increased progressively as the corrosion temperature and time increased. Corrosion resistance increased in the order of T22, T91, T92, 347HFG, and 310H, suggesting that the alloying elements of Cr, Ni, and W beneficially improved the corrosion resistance of steels. Basically, Fe oxidized to $Fe_2O_3$, and Cr oxidized to $Cr_2O_3$, some of which further reacted with FeO to form $FeCr_2O_4$ or with NiO to form $NiCr_2O_4$.

• Journal of Internet Computing and Services
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• v.22 no.5
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• pp.27-33
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• 2021

With the broad adoption of the Internet of Things (IoT) in a variety of scenarios and application services, management and orchestration entities require upgrading the traditional architecture and develop intelligent models with ultra-reliable methods. In a heterogeneous network environment, mission-critical IoT applications are significant to consider. With erroneous priorities and high failure rates, catastrophic losses in terms of human lives, great business assets, and privacy leakage will occur in emergent scenarios. In this paper, an efficient resource slicing scheme for optimizing federated learning in software-defined IoT (SDIoT) is proposed. The decentralized support vector regression (SVR) based controllers predict the IoT slices via packet inspection data during peak hour central congestion to achieve a time-sensitive condition. In off-peak hour intervals, a centralized deep neural networks (DNN) model is used within computation-intensive aspects on fine-grained slicing and remodified decentralized controller outputs. With known slice and prioritization, federated learning communications iteratively process through the adjusted resources by virtual network functions forwarding graph (VNFFG) descriptor set up in software-defined networking (SDN) and network functions virtualization (NFV) enabled architecture. To demonstrate the theoretical approach, Mininet emulator was conducted to evaluate between reference and proposed schemes by capturing the key Quality of Service (QoS) performance metrics.