• Journal of the Korean Wood Science and Technology
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• v.37 no.3
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• pp.192-199
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• 2009

This study was carried out to investigate the performance of a radio-frequency/vacuum dryer combined with a mechanical compressive load (RF/VC) with a scale of about $3m^3$ during drying board of Azobe (Lophira alata) and Korean red pine (Pinus densiflora). The degree of vacuum of the RF/VC system was maintained at 80~105 torr, and wood temperature was increased from $40^{\circ}C$ at the beginning of drying to $60^{\circ}C$ at the end of drying and the radiofrequency generator was operated with schedule of 7 minute-ON and 3 minute-OFF. The wood temperatures near charge plate always remained higher than those of the control during all of the drying stage, whereas the wood temperature near ground plate always remained lower than those of the controlled. As drying time proceeding, the temperature of the wood near ground plate presented lower than those of the control. Whereas the temperature of the wood near charge plate presented higher than those of the controlled. The final average moisture contents of the Azobe boards stacked near the input side of the RF generator showed slightly lower than those near the opposite side. Those of the wood stacked in the layers near the charge plate were lower than those of near the ground plate. The average length of surface checks of the Azobe boards stacked near the charge plate was very slight, whereas that toward the ground plate represented high values. The efficiency of input energy was simliar with the commercial systems.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.2
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• pp.191-197
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• 2005

A new method, ToxTemp (TOXcity test based on TEMPerature control) using Ceridaphnia dubia was applied to evaluate the toxicity of insecticide materials and compared with the standard 48 hr acute bioassay. BPMC, diazinon and fenitrothion may cause the inhibition to the biological process in sewage treatment plant and need to detect toxicity within short contact time. The ToxTemp method showed sensitive detection with more shorter contact of 1-1.5 hr time than that of the standard 48 hr acute bioassay. To evaluate toxicity of real wastewater/sewage, the inhibition rate of nitrification and oxygen uptake rate (OUR) using activated sludge, the standard 48hr acute bioassay and ToxTemp method using C. dubia were compared, respectively. On the basis of the inhibition rate of nitrification, the OUR test showed the less sensitive results at the relatively strong toxic sewage. On the other hands, the standard 48hr acute bioassay and ToxTemp method using C. dubia represented the toxicity of each wastewater/sewage with high sensitivity. Even the slightly low (about 1.5%) sensitivity, the ToxTemp method showed the high applicability to the real site of sewage treatment plant.

• JSTS:Journal of Semiconductor Technology and Science
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• v.5 no.3
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• pp.149-158
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• 2005

This paper describes design, fabrication, and application of the silicon based temperature controllable micro reactor. In order to achieve fast temperature variation and low energy consumption, reaction chamber of the micro reactor was thermally isolated by etching the highly conductive silicon around the reaction chamber. Compared with the model not having thermally isolated structure, the thermally isolated micro reactor showed enhanced thermal performances such as fast temperature variation and low energy consumption. The performance enhancements of the micro reactor due to etched holes were verified by thermal experiment and numerical analysis. Regarding to 42 percents reduction of the thermal mass achieved by the etched holes, approximately 4 times faster thermal variation and 5 times smaller energy consumption were acquired. The total size of the fabricated micro reactor was $37{\times}30{\times}1mm^{3}$. Microchannel and reaction chamber were formed on the silicon substrate. The openings of channel and chamber were covered by the glass substrate. The Pt electrodes for heater and sensor are fabricated on the backside of silicon substrate below the reaction chamber. The dimension of channel cross section was $200{\times}100{\mu}m^{2}$. The volume of reaction chamber was $4{\mu}l$. The temperature of the micro reactor was controlled and measured simultaneously with NI DAQ PCI-MIO-16E-l board and LabVIEW program. Finally, the fabricated micro reactor and the temperature control system were applied to the thermal denaturation and the trypsin digestion of protein. BSA(bovine serum albumin) was chosen for the test sample. It was successfully shown that BSA was successfully denatured at $75^{\circ}C$ for 1 min and digested by trypsin at $37^{\circ}C$ for 10 min.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.11
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• pp.99-107
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• 2013

Controller area network (CAN) was designed for multiplexing communication between electronic control units (ECUs) in vehicles and thus for decreasing the overall wire harness. The increasing number of ECUs causes the CAN bus overloaded and consequently the error probability of data transmission increases. Since the time duration for the data transmission is proportional to CAN frame length, it is desirable to reduce the frame length. In this paper, a CAN message compression method is proposed using Data Length Code (DLC) and compression area selection algorithm to reduce the CAN frame length and the error probability during the transmission of CAN messages. By the proposed method, it is not needed to predict the maximum value of the difference in successive CAN messages as opposed to other compression methods. Also, by the use of DLC, we can determine whether the received CAN message has been compressed or not without using two ID's as in conventional methods. By simulations using actual CAN data, it is shown that the CAN transmission data is reduced up to 52 % by the proposed method, compared with conventional methods. By using an embedded test board, it is shown that 64bit EMS CAN data compression can be performed within 0.16ms and consequently the proposed algorithm can be used in automobile applications without any problem.

• The KIPS Transactions:PartD
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• v.11D no.2
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• pp.443-452
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• 2004

The paper presents an intelligent space management system for ubiquitous computing. The system is basically a home/office automation system that could control light, electronic key, and home appliances such as TV and audio. On top of these basic capabilities, there are four elegant features in the system. First, we can access the system using either a cellular Phone or using a browser on the PC connected to the Internet, so that we control the system at any time and any place. Second, to provide more human-oriented interface, we integrate voice recognition functionalities into the system. Third, the system supports not only reactive services but also proactive services, based on the regularities of user behavior. Finally, by exploiting embedded technologies, the system could be run on the hardware that has less-processing power and storage. We have implemented the system on the embedded board consisting of StrongARM CPU with 205MHz, 32MB SDRAM, 16MB NOR-type flash memory, and Relay box. Under these hardware platforms, software components such as embedded Linux, HTK voice recognition tools, GoAhead Web Server, and GPIO driver are cooperated to support user-friendly intelligent space.

• Journal of Marine Life Science
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• v.7 no.1
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• pp.29-36
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• 2022

Sea cucumber, Aposticopus japonicus, is a major invertebrate species in the coastal regions of Korea. To evaluate the short-term stress levels according to the releasing methods, this study investigated the gene expression profiles of heat shock protein 90 (HSP90) by real-time quantitative polymerase chain reaction. When the juvenile sea cucumbers were packed in the vinyl bag with oxygen followed by transportation for 30 min or air-exposed for 1 h, the HSP90 gene expression levels in the experimental groups were significantly increased compared to those of the control groups (transported group, p=0.001; air-exposed group, p=0.032). The experimental group at 6 h post-release by seed-spreading method and at 2~6 h post-release by underwater hose-releasing method on board a fishing boat showed that the levels of HSP90 gene expression were not statistically significant but decreased slightly compared to the control group (seed-spreading group, p=0.069; hose-releasing group, p=0.093). On the other hand, the HSP90 gene expression showed an increasing pattern as the time passed (~6 h) after underwater release of juvenile sea cucumbers by divers (p=0.061). These results suggest that HSP90 gene expression can be used to investigate short-term stress response and effective releasing methods of juvenile sea cucumbers.

• Journal of Biomedical Engineering Research
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• v.43 no.2
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• pp.81-93
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• 2022

Proprioception training has been considered a secondary method to facilitate postural control ability. This study investigated the effects of two different proprioception training methods - the proprioceptive neuromuscular facilitation (PNF) and visual feedback-based joint position and force reproduction (VF) - on postural control advancements. Sixteen healthy people volunteered for this study, and they randomly grouped two. Each group participated in the PNF and VF training for three weeks. We evaluated each subject's proprioception levels and balance ability before and after the training. We used a clinometer and electromyogram (EMG) for VF training. The joint position reproduction test was also used to evaluate the position and force aspects of the proprioception level. We analyzed the trajectory of the center of pressure (COP) while subjects were standing on the firm floor and balance board with one leg using a pressure mat. The improvement of the position aspect of the proprioception level of the VF group (4.93±4.74°) was larger than that of the PNF group (-0.43±2.08°) significantly (p=0.012). The improvement of the anterior-posterior COP velocity of the PNF group (0.01±0.01 cm/s) was larger than that of VF group(0.002±0.01 cm/s) significantly (p=0.046). Changes of position error in the PNF group (rho=0.762, p=0.028) and tibialis anterior force reproduction error in the VF group showed a significantly strong relationship with balance ability variables. These results showed that different PNF and VF have different effects on improving two aspects of proprioception and their relationship with the balance ability. Therefore, these results might be useful for selecting proprioception or balance rehabilitation considering the clinical and patients' situation.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.7 no.6
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• pp.719-729
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• 2017

Recently, the field of agriculture has been gaining a new leap with the integration of ICT technology in agriculture. In particular, smart farms, which incorporate the Internet of Things (IoT) technology in agriculture, are in the spotlight. Smart farm technology collects and analyzes information such as temperature and humidity of the environment where crops are cultivated in real time using sensors to automatically control the devices necessary for harvesting crops in the control device, Environment. Although smart farm technology is paying attention as if it can solve everything, most of the research focuses only on increasing crop yields. This paper focuses on the development of a system architecture that can harvest high quality crops at the optimum stage rather than increase crop yields. In this paper, we have developed an architecture using apple trees as a sample and used the color information and weight information to predict the harvest time of apple trees. The simple board that collects color information and weight information and transmits it to the server side uses Arduino and adopts model-driven development (MDD) as development methodology. We have developed an architecture to provide services to PC users in the form of Web and to provide Smart Phone users with services in the form of hybrid apps. We also developed an architecture that uses beacon technology to provide orchestration information to users in real time.

• Journal of Advanced Navigation Technology
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• v.28 no.3
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• pp.254-261
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• 2024

Accurate guidance during landing and take-off is important, and instrument landing system (ILS) has been used for stability and verification. Regular inspections are conducted for stable operation, and there is research to perform inspection using drones in addition to ground vehicles and measurement aircraft. Using SDR and single board computer, which can receive wide frequency range, we designed a small system that receives and processes localizer signals through GNU Radio. To check signal processing characteristics through GNU Radio, we simulated with MATLAB Simulink and confirmed the theoretical values. Difference in depth of modulation (DDM) and approach angle can be calculated when the aircraft enters the runway. And GNU Radio implemented real-time signal processing wirelessly using transmission control protocol (TCP). This gives the results within the error of 0.5% when the aircraft entered the runway center line and 0.27% for the angle of 1° degree. Compared to the inspecting and maintaining ILS signals using aircraft or ground vehicles, it is possible to implement a receiving system using small SDR that can be mounted for drone.

• Korean Journal of Agricultural Science
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• v.17 no.1
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• pp.1-8
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• 1990

The paper board sludge(PBS) itself and compost sludge manure(CSM) mixed with sawdust, fowl droppings and urea to the PBS were treated to soybean plants to find the effects of growing characters, yield components, and nutritional compounds in the plant tissues. 1. Percentages of missing plants were 5-9% and 3.6-4.1% in the treatments of PBS and CSM, respectively. After that, the plants were restored to normal conditions. Anyway it is not desirable to use the paper board sludge and immature compost sludge manure in seeding time or to young seedlings. 2. Growth of the plant height was retarded in early growing phase, but it was normal in later stages. And the width and length of the largest leaf, numbers of main stem nodes and pods were not significant among the treatments. 3. The yield intends to increase through the treatments of 1,200, 1,600, and 2,000Kg PBS per 10a. In the CSM treatments with high rate of sawdust, fowl droppings and urea, the numbers of pods and grains were higher than the treatment of high content of PBS. 100-grain and one liter weights were opposite intention. It was suggested that the excess nitrogen amounts from the compost sludge manure than conventional fertilization affected to the yield components. 4. The contents of the main chemical compounds such as N, $P_2O_5$, $K_2O$, Ca, Mg were determined. The concentrations of nitrogen were higher in the treatment of PBS and CSM than none and control. 5. In conclusion, the nutritional effects of PBS were in evidence. To use the sludges, it should be fermented with adequate additives to improve the aeration, C/N ratio, activity of microbial, and other conditions. The sludges could be used to crops as a fertilizers effectively.