• Journal of Astronomy and Space Sciences
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• v.20 no.4
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• pp.339-350
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• 2003

Engineering qualification model payload for a communications and broadcasting satellite(CBS) was developed by ETRI from May, 2000 to April, 2003. For. the purpose of functional test and verification of the payload, a real-time hardware-in-the-loop(HITL) CBS simulator(CBSSIM) was also developed. We assumed that the spacecraft platform for the CBSSIM is a geostationary communication satellite using momentum bias three-axis stabilization control technique based on Koreasat. The payload hardware is combined with CBSSIM via Power, Command and Telemetry System(PCTS) of Electrical Ground Support Equipment(EGSE). CBSSIM is connected with PCTS by TCP/IP and the payload is combined with PCTS by MIL-STD-1553B protocol and DC harness. This simulator runs under the PC-based simulation environment with Windows 2000 operating system. The satellite commands from the operators are transferred to the payload or bus subsystem models through the real-time process block in the simulator. Design requirements of the CBSSIM are to operate in real-time and generate telemetry. CBSSIM provides various graphic monitoring interfaces and control functions and supports both pre-launch and after-launch of a communication satellite system. In this paper, the HITL simulator system including CBSSIM, communications payload and PCTS as the medium of interface between CBSSIM and communications payload will be described in aspects of the system architecture, spacecraft models, and simulator operation environment.

• KIPS Transactions on Software and Data Engineering
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• v.5 no.12
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• pp.623-634
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• 2016

Most of existing frequent pattern mining methods address time efficiency and greatly rely on the primary memory. However, in the era of big data, the size of real-world databases to mined is exponentially increasing, and hence the primary memory is not sufficient enough to mine for frequent patterns from large real-world data sets. To solve this problem, there are some researches for frequent pattern mining method based on disk, but the processing time compared to the memory based methods took very time consuming. There are some researches to improve scalability of frequent pattern mining, but their processes are very time consuming compare to the memory based methods. In this paper, we present PPFP as a novel disk-based approach for mining frequent itemset from big data; and hence we reduced the main memory size bottleneck. PPFP algorithm is based on FP-growth method which is one of the most popular and efficient frequent pattern mining approaches. The mining with PPFP consists of two setps. (1) Constructing an IFP-tree: After construct FP-tree, we assign index number for each node in FP-tree with novel index numbering method, and then insert the indexed FP-tree (IFP-tree) into disk as IFP-table. (2) Mining frequent patterns with PPFP: Mine frequent patterns by expending patterns using stack based PUSH-POP method (PPFP method). Through this new approach, by using a very small amount of memory for recursive and time consuming operation in mining process, we improved the scalability and time efficiency of the frequent pattern mining. And the reported test results demonstrate them.

• Journal of Korean Society of Water and Wastewater
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• v.31 no.6
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• pp.501-510
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• 2017

In this study, it is estimated that ceramic membrane process which can operate stably in harsh conditions replacing existing organic membrane connected with coagulation, sedimentation etc.. Jar-test was conducted by using artificial raw water containing kaolin and humic acid. It was observed that coagulant (A-PAC, 10.6%) 4mg/l is the optimal dose. As a results of evaluation of membrane single filtration process (A), coagulation-membrane filtration process (B) and coagulation-sedimentation-membrane filtration process (C), TMP variation is stable regardless of in Flux $2m^3/m^2{\cdot}day$. But in Flux $5m^3/m^2{\cdot}day$, it show change of 1-89.3 kpa by process. TMP of process (B) and (C) is increased 11.8, 0.6 kpa each. But, the (A) showed the greatest change of TMP. When evaluate (A) and (C) in Flux $10m^3/m^2{\cdot}day$, TMP of (A) stopped operation being exceeded 120 kpa in 20 minutes. On the other hand, TMP of (C) is increased only 3 kpa in 120 minutes. Through this, membrane filtration process can be operated stably by using the linkage between the pretreatment process and the ceramic membrane filtration process. Turbidity of treated water remained under 0.1 NTU regardless of flux condition and DOC and $UV_{254}$ showed a removal rate of 65-85%, 95% more each at process connected with pretreatment. Physical cleaning was carried out using water and air of 500kpa to show the recovery of pollutants formed on membrane surface by filtration. In (A) process, TMP has increased rapidly and decreased the recovery by physical cleaning as the flux rises. This means that contamination on membrane surface is irreversible fouling difficult to recover by using physical cleaning. Process (B) and (C) are observed high recovery rate of 60% more in high flux and especially recovery rate of process (B) is the highest at 95.8%. This can be judged that the coagulation flocs in the raw water formed cake layer with irreversible fouling and are favorable to physical cleaning. As a result of estimation, observe that ceramic membrane filtration connected with pretreatment improves efficiency of filtration and recovery rate of physical cleaning. And ceramic membrane which is possible to operate in the higher flux than organic membrane can be reduce the area of water purification facilities and secure a stable quantity of water by connecting the ceramic membrane with pretreatment process.

• Journal of Soil and Groundwater Environment
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• v.13 no.4
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• pp.62-68
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• 2008

The Low Temperature Thermal Desorption (LTTD) System equipped with a soil transfer unit, a rotary kiln, RTO, cyclones and a bag filter etc. was developed. The LTTD system was designed to be economically operated using LPG as a fuel and recirculating the discharged gas from the LTTD system through RTO. For the performance test of LTTD system the soil contaminated with light and heavy oils (2,690 mg TPH/kg soil) and with particle sizes below 50 mm was fed into the rotary kiln of LTTD system at 7$m^3$/hr with retention time of 15 minutes. Operation temperatures of LTTD system for the removal of soil TPH were $567^{\circ}C$ and $692^{\circ}C$. The residual TPH after treatment was 46 mg/kg and 32mg/kg respectively at each temperature condition, which shows high TPH removal efficiencies of the developed LTTD as 98.3% and 98.9%.

• Journal of the Korean Society of Marine Environment & Safety
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• v.25 no.6
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• pp.772-779
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• 2019

The subsea pipeline has received considerable attention as a high-value-added industry linked to the energy and steel industries including natural resource development. The design and installation of the subsea pipeline require a variety of key technologies to carry out the project. In particular, a thorough pre-verification process through pre-commissioning is essential for the safe operation of the subsea pipeline. The hydrotesting stage in the pre-commissioning process of the subsea pipeline is known to be affected significantly by the ambient temperature change; however, there is a little study based on the theoretical and numerical approach. In this study, the method of predicting the internal temperature change using the transient heat transfer method for the stage of hydrotesting during the pre-commissioning process of the subsea pipeline and the prediction method of the pressure variation in the pipeline using it were proposed. The predicted results were compared with field test results and its effectiveness was verified. The proposed analysis procedure is expected to contribute to the productivity improvement of the subsea pipeline installation project by enabling the prediction of pressure variation through pipeline heat transfer simulation from the initial design stage of the subsea pipeline installation project.

• Journal of the Ergonomics Society of Korea
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• v.35 no.1
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• pp.11-27
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• 2016

Objective: The purpose of this study was to develop and evaluate high technology adaptive driving controls, such as mini steering wheel-lever system and joystick system, for the people with physical disabilities in the driving simulator. Background: The drivers with severe physical disabilities have problems in operation of the motor vehicle because of reduced muscle strength and limited range of motion. Therefore, if the remote control system with driver-by-wire technology is used for adaptive driving controls for people with physical limitations, the disabled people can improve their quality of life by driving a motor vehicle. Method: We developed the remotely controlled driving simulator with drive-by-wire technology, e.g., mini steering wheel-lever system and joystick system, in order to evaluate driving performance in a safe environment for people with severe physical disabilities. STISim Drive 3 software was used for driving test and the customized Labview program was used in order to control the servomotors and the adaptive driving devices. Thirty subjects participated in the study to evaluate driving performance associated with three different driving controls: conventional driving control, mini steering wheel-lever controls and joystick controls. We analyzed the driving performance in three different courses: straight lane course for acceleration and braking performance, a curved course for steering performance, and intersections for coupled performance. Results: The mini steering wheel-lever system and joystick system developed in this study showed no significant statistical difference (p>0.05) compared to the conventional driving system in the acceleration performance (specified speed travel time, average speed when passing on the right), steering performance (lane departure at the slow curved road, high-speed curved road and the intersection), and braking performance (brake reaction time). However, conventional driving system showed significant statistical difference (p<0.05) compared to the mini steering wheel-lever system or joystick system in the heading angle of the vehicle at the completion point of intersection and the passing speed of the vehicle at left turning. Characteristics of the subjects were found to give a significant effect (p<0.05) on the driving performance, except for the braking reaction time (p>0.05). The subjects with physical disabilities showed a tendency of relatively slow acceleration (p<0.05) at the straight lane course and intersection. The steering performance and braking performance were confirmed that there was no statistically significant difference (p>0.05) according to the characteristics of the subjects. Conclusion: The driving performance with mini steering wheel-lever system and joystick control system showed no significant statistical difference compared to conventional system in the driving simulator. Application: This study can be used to design primary controls with driver-by-wire technology for adaptive vehicle and to improve their community mobility for people with severe physical disabilities.

• Journal of Acupuncture Research
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• v.15 no.2
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• pp.105-116
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• 1998

Purpose In this study, We observed the recovery process in the ability to move in the hind limbs of the rats whose spinal cord injuries were treated by Radix acouniti(RA). The purpose of this study is to see the effects of Radix acouniti(RA) water extract on the contraction of rat's spinal cord injury. Procedure First, the rats were subjected to hemisectional spinal cord injuries by a scalpel blade. Those rats, then, were divided into three groups: Sham operated rats group and the experimental group, which received the Radix acouniti(RA) water extract, and the control group, which had no treatment. Their recovery in the ability to walk was observed by the Open Field Test (OFT) for 14 days after the injuries. Method The OFT was applied at four points: the hip, knee, ankle joint, and the tail. Each joint was given a movement rating of from 0 to 3, depending on the amount of movement. A movement rating of 0 designates no movement, a 1 designates slight movement, a 2 designates increased movement, and a 3 designates active movement. Slight movement is defined as a joint displaying less than or equal to 30% of that joint range, increased movement is displaying less than or equal to 60% of that joint's range, and active movement is greater than or equal to 90% of that joint's range. Tail movement is also graded on a scale of 0 to 3. A rating of 0 indicates that the tail is down 100% of the time, one of 1 indicates that the tail is down more than 10%, one of 2 shows that the tail is down less than 50% but more than 10% of the time, and one of 3 shows that the tail is down less than 10% of the time. All four ratings were added together and then averaged to arrive at a single score. Results The sham group which did not go through spinal cord injuries showed near normal results on all 3 joints and tail from right after the operation, which one would expect. The RA oral application group showed more effective recovery of movememt function than the control group around 4 days after the spinal cord injuries. However, after 14 days, both groups displayed almost the same degree of movement recovery. The results of this study are summarized as follows: 1. After 14days the spinal cord injuries, movement was recovered in sham operated group, control group, and experimented group in the hip, the knee, the tail and then the ankle of rats, in that order. 2. Around 7 days after the spinal cord injuries, the experimental group proved the effectiveness of the therapy in terms of movement recovery. 3. The level of ALT, ALP, AST in RA treated group was slightly increased. 4. The level of BUN and creatinine in RA treated group was slightly increased. The above results indicate that RA therapy at an early stage can bring about better movement recovery in patients with spinal cord injuries from traffic accidents or industrial disasters. But there is apparent side effect of RA on clinical, therefore the study on this should be continued.

• Journal of Acupuncture Research
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• v.25 no.1
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• pp.121-130
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• 2008

Objectives : Cupping therapy is a stimulation therapy similar to acupuncture and moxibustion with effects that differ depending on the degree of stimulus. To make the strength of the skin objective in cupping therapy for this study, we measured negative pressure in the cupping jar and calculated the expansion rate of the skin. Subjects and Methods : In this study, we experimented with cupping therapy jars made for sale and used in clinics. We studied the pressure in the jars and the changes on the skin surface by measuring properties. We used commercial jars of four different volumes and diameters and tried to discover the properties on the size of the jar. Results : The results of experiment with the cupping therapy are as follows: 1. The lowest pressure in a jar was measured at $-600{\sim}610mmHg$, and the number of operating of vacuum pump for reaching lowest pressure was increased recording where the volume of the jar would be big, but the lowest pressure was not increased recording where the size of that would be big. 2. As the vacuum pump continued to operate, the pressure gradient in the jar got smaller which shows that the expansion rate of the skin was not linear. The pressure gradient shows different operational numbers on the vacuum pump near 0mmHg/operation unrelated to jar volume. 3. When negative pressure worked on the jar, air in the jar decreased. The percentage of air gradually reduced as the negative pressure acted in the jar. For example, the percentage of skin was 37-66% when the negative pressure, reatched -500mmHg. According to out results, different test areas generate different percentages of air in the jar, presumably related to skin elasticity. This phenomenon was most pronounced with the smallest jars. 4. At -500mmHg, the expansion rate of the skin was 1.57-1.9 on the abdomen, and $1.52{\sim}1.68$ on the back. The expansion rate of the skin appeared greater when the jar was relatively small, and it appeared smaller when the jar volume was relatively large relatively.

• Journal of the Korean Arthroscopy Society
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• v.12 no.1
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• pp.32-39
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• 2008

Purpose: To evaluate the effectiveness of MRI after ACL reconstruction with femoral tunnel at 10 o'clock position. Materials and Methods: MRI findings of 29 patients after ACL reconstruction using hamstring tendon autograft were evaluated. The mean period from operation to MRI was 18.9 months($7{\sim}40$ months). Signal intensity, morphology and continuity of graft, femoral insertion, graft angle, roof impingement, cross pin breakage and position were evaluated. Those findings were compared with KT-2000, Lysholm knee score and pivot shift test. Results: There was no significant correlation between signal intensity of graft and the duration to MRI. Most common pattern of the morphology was straight, and the continuity was well-preserved. 13 cases of femoral tunnel insertion were zone 4 and 16 were zone 3. There were no roof impingement. 10 cases showed cross pin breakages, of which 5 were found at the outside of distal femoral posterior cortex. 9 showed cross pin directed posteriorly in axial view. There was no significant correlation between clinical results and cross pin breakage. Conclusion: MRI examinations after ACL reconstructions are useful to evaluate the graft status, position of the graft and cross pins. Since the direction of the cross pin is important especially in 10 o'clock femoral position, care should be taken to avoid cross pin breakage.

• Journal of the Korean Association of Geographic Information Studies
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• v.9 no.3
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• pp.25-35
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• 2006

Standardization or standard-related study are regarded as main issues in GIS applications. Though several GIS standards and specifications have been released, there are a few actual application cases adapting those. In this study, we designed and implemented a geo-spatial information processing system with editing, storing, and disseminating functions, in which standard GIS transportation data model by TTA linked with OGC-GML, XML-based geographic features encoding standard. The system developed in this study enables us to transfer and edit transportation entities based on TTA standards to GML, importing ESRI shapefile. In web-based system, GML-based databases are transformed to SVG file, for the purpose of web publishing. TTA GIS transportation data model is used in this study, and tested; however, standard data models from other application fields also can be easily applied because this system basically provides data importing and editing functions. This system as practical tools can be utilized for applicability test of GIS standard data model and practical operation of standard specification.