• Journal of Platform Technology
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• v.11 no.2
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• pp.26-38
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• 2023

This paper is a study on a transport robot capable of autonomously driving to a destination using a QR code in an indoor environment. The transport robot was designed and manufactured by attaching a lidar sensor so that the robot can maintain a certain distance during movement by detecting the distance between the camera for recognizing the QR code and the left and right walls. For the location information of the delivery robot, the QR code image was enlarged with Lanczos resampling interpolation, then binarized with Otsu Algorithm, and detection and analysis were performed using the Zbar library. The QR code recognition experiment was performed while changing the size of the QR code and the traveling speed of the transport robot while the camera position of the transport robot and the height of the QR code were fixed at 192cm. When the QR code size was 9cm × 9cm The recognition rate was 99.7% and almost 100% when the traveling speed of the transport robot was less than about 0.5m/s. Based on the QR code recognition rate, an experiment was conducted on the case where the destination is only going straight and the destination is going straight and turning in the absence of obstacles for autonomous driving to the destination. When the destination was only going straight, it was possible to reach the destination quickly because there was little need for position correction. However, when the destination included a turn, the time to arrive at the destination was relatively delayed due to the need for position correction. As a result of the experiment, it was found that the delivery robot arrived at the destination relatively accurately, although a slight positional error occurred while driving, and the applicability of the QR code-based destination self-driving delivery robot was confirmed.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.39 no.3
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• pp.218-229
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• 2003

A new biotelemetry method that the installation and the treatment of equipment is convenient and the instantaneously detailed location of the fish attached the pinger is able to track comparatively easily was developed. The receiving system in this biotelemetry method was advanced for track the detailed behavior of the fish by the miniature tracking pinger, because it was a burden to fish to add the pinger with the water temperature and the pressure sensor. By combining of the super short base line (SSBL) method to detect the direction of pinger and the pinger synchronizing method to measure the range from receiving transducer to pinger, the three dimensional locations of fish to the receiving transducer is gotten instantaneously. The receiving system is devised to realize the high precision or wide detection range by application of the basic design method for receiving system of biotelemetry developed by the present authors and the hydrophone array configuration. The measurement distance error in the pinger synchronizing method is minimized through the correction of which the deviation of transmission pluse period of pinger is caused by changing water temperature. A prototype system which is able to track the instantaneously detailed location of the fish by the SSBL and pinger synchronizing biotelemetry (SPB) method was produced.

• Journal of Korean Society of Rural Planning
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• v.20 no.1
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• pp.51-62
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• 2014

The composition of rural Green Village requires higher utilization of renewable energy in those selected rural villages. The purpose of this study is to select the best results of rural green villages when using photovoltaic power system(PV system). 10 different rural villages in Chubumyeon, Keumsan, Chungnam province, were selected as study villages. This study shows measured solar radiation data, a 20-year time series data, and GIS spatial analysis; and whose were used to predict the photovoltaic power generation. PV system is used as a form with capacity of 3kWp to use for personal and public houses. Generation data was calculated by the town, where the economics of the Green Village location analysis was performed; and the solar radiation's correction factor was calculated by the 20-year time series data and measured data by study villages. By applying to the data of DEM, slope and aspect of the study villages were found, therefore performed. Spatial analysis tools were performed by using solar radiation map's tools. Those data found were used to calculate the average needed energy every months. When used the properly calculated data, towns performed economical energy consumption in rural Green Village. Every study villages have showed very high potential for PV system. Sungdangri ranked at the first (7,401kWp/year), Jangdaeri follows behind to the second (7,203kWp/year) and Yogwangri at third (7,89kWp/year) which shows higher developed energy than other study villages. The areas covered of these three towns are as follows: Sungdangri at $33,300m^2$, Jangdaeri covers $18,000m^2$ and Yogwangri shows $46,800m^2$. With these results, analyzing the potentials using GIS spatial analysis before installation of PV system was possible. Also different villages and topography in study villages have showed various results by the area. For convenience and to shorten research time, it is possible and enough to use solar radiation tools when studying spatial analysis of solar radiation.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.2
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• pp.299-306
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• 2016

Body temperature (BT) monitoring in cattle could be used to early detect fever from infectious disease or physiological events. Various ways to measure BT have been applied at different locations on cattle including rectum, reticulum, milk, subcutis and ear canal. In other to evaluate the temperature stability and reliability of subcutaneous temperature (ST) in highly fluctuating field conditions for continuous BT monitoring, long term ST profiles were collected and analyzed from cattle in autumn/winter and summer season by surgically implanted thermo-logger devices. Purposes of this study were to assess ST in the field condition as a reference BT and to determine any location effect of implantation on ST profile. In results, ST profile in cattle showed a clear circadian rhythm with daily lowest at 05:00 to 07:00 AM and highest around midnight and rather stable temperature readings (mean${\pm}$standard deviation [SD], $37.1^{\circ}C$ to $37.36^{\circ}C{\pm}0.91^{\circ}C$ to $1.02^{\circ}C$). STs are $1.39^{\circ}C$ to $1.65^{\circ}C$ lower than the rectal temperature and sometimes showed an irregular temperature drop below the normal physiologic one: 19.4% or 36.4% of 54,192 readings were below $36.5^{\circ}C$ or $37^{\circ}C$, respectively. Thus, for BT monitoring purposes in a fever-alarming-system, a correction algorithm is necessary to remove the influences of ambient temperature and animal resting behavior especially in winter time. One way to do this is simply discard outlier readings below $36.5^{\circ}C$ or $37^{\circ}C$ resulting in a much improved mean${\pm}$SD of $37.6^{\circ}C{\pm}0.64^{\circ}C$ or $37.8^{\circ}C{\pm}0.55^{\circ}C$, respectively. For location the upper scapula region seems the most reliable and convenient site for implantation of a thermo-sensor tag in terms of relatively low influence by ambient temperature and easy insertion compared to lower scapula or lateral neck.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.18 no.5
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• pp.77-87
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• 2018

Many researches have been focused on localization in WSNs. However, the solutions for localization in static WSN are hard to apply to the mobile WSN. The solutions for mobile WSN localization have the assumption that there are a significant number of anchor nodes in the networks. In the resource limited situation, these solutions are difficult in applying to the static and mobile mixed WSN. Without using the anchor nodes, a localization service cannot be provided in efficient, accurate and reliable way for mixed wireless sensor networks which have a combination of static nodes and mobile nodes. Also, accuracy is an important consideration for localization in the mixed wireless sensor networks. In this paper, we presented a method to satisfy the requests for the accuracy of the localization without anchor nodes in the wireless sensor networks. Hop coordinates measurements are used as an accurate method for anchor free localization. Compared to the other methods with the same data in the same category, this technique has better accuracy than other methods. Also, we applied a minimum spanning tree algorithm to satisfy the requests for the efficiency such as low communication and computational cost of the localization without anchor nodes in WSNs. The Java simulation results show the correction of the suggested approach in a qualitative way and help to understand the performance in different placements.

• Geophysics and Geophysical Exploration
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• v.11 no.1
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• pp.15-25
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• 2008

Ocean-bottom seismometer (OBS) positions are one of the key parameters in an OBS-airgun seismic survey for crustal structure study. To improve the quality of these parameters, we have developed a new method of determining OBS positions, using airgun shot data and bathymetric data in addition to available distance measurements by acoustic transponders. The traveltimes of direct water waves emitted by airgun shots and recorded by OBSs are used as important information for determining OBS locations, in cases where there are few acoustic transponder data (<3 sites). The new method consists of two steps. A global search is performed as the first step, to find nodes of the bathymetric grid that are the closest to explaining the observed direct water-wave traveltimes from airgun shots, and acoustic ranging using a transponder system. The use of precise 2D bathymetric data is most important if the bottom topography near the OBS is extremely rough. The locations of the nodes obtained by the first step are used as initial values for the second step, to avoid falling into local convergence minima. In the second step, a non-linear inverse method is executed. If the OBS internal clock shows large drift, a secondary correction for the OBS internal clock is obtained, as well as the OBS location, as final results by this method. We discuss the error and the influence of each measurement used in the determination of OBS location.

• Archives of Plastic Surgery
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• v.33 no.2
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• pp.149-154
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• 2006

The levator and $M{\ddot{u}}ller^{\prime}s$ muscle balanced tucking was performed to correction myogenic or aponeurotic blepharoptosis. Through the blepharoplasty incision, the upper half of tarsal plate was exposed and the orbital was opened to show the levator aponeurosis. the $M{\ddot{u}}ller^{\prime}s$ muscle dissected from the upper border of the tarsal plate and from the posteriorly located conjunctiva with sharp scissors. $M{\ddot{u}}ller^{\prime}s$ muscle was advanced about 3 mm to 8 mm on anterior surface of the tarsal plate and fixed approximately upper one third of the tarsal plate with three horizontal 6-0 Nylon mattress sutures. The amount of tucking of $M{\ddot{u}}ller^{\prime}s$ muscle was controlled by the location of the upper eyelid margin 2 mm below the upper limbus in primary gaze after first temporary fixations suture in the maximum superior point of the limbus. The amount of advancement of levator aponeurosis was controlled by the location of the upper eyelid margin 1 mm below the upper limbus in primary gaze after first temporary fixations suture in the maximum superior point of the limbus. And then levator aponeurosis was fixed with three horizontal 6-0 Nylon mattress on beside the point that was tucked $M{\ddot{u}}ller^{\prime}s$ muscle. We have been thirty cases with levator and $M{\ddot{u}}ller^{\prime}s$ muscle balanced tucking from January 2004 to Jun 2005. 3 cases were traumatic blepharoptosis with 3-5 mm ptosis and poor levator function. 27 cases were myogenic or aponeurotic blepharoptosis with 2-5 mm ptosis with and more than 4 mm of levator function. the age of the patients ranged from 6 to 78 years. The levator aponeurosis and $M{\ddot{u}}ller^{\prime}s$ muscle tucking procedure can reduce the amount of the levator and $M{\ddot{u}}ller^{\prime}s$ muscle resection, and improve discomfort when the patients open eyes.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.17 no.5
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• pp.85-90
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• 2017

Indoor location-based services have been developed based on the Internet of Things technologies which measure and analyze users who are moving in their daily lives. These various indoor positioning technologies require separate hardware and have several disadvantages, such as a communication protocol which becomes complicated. Based on the fact that a reduction in signal strength occurs according to the distance due to the physical characteristics of the transmitted signal, RSSI technology that uses the received signal strength of the wireless signal used in this paper measures the strength of the transmitted signal and the intensity of the attenuated received signal and then calculates the distance between a transmitter and a receiver, which requires no separate costs and makes to implement simple measurements. It was applied calculating the value for the average RSSI and the RSSI filtering feedback. Filtering is used to reduce the error of the RSSI values that are measured at long distance.It was confirmed that the RSSI values through the average filtering and the RSSI values measured by setting the coefficient value of the feedback filtering to 0.5 were ranged from -61 dBm to - 52.5 dBm, which shows irregular and high values decrease slightly as much as about -2 dBm to -6 dBm as compared to general measurements.

• The KIPS Transactions:PartA
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• v.13A no.4 s.101
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• pp.335-342
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• 2006

As PRC linear interpolation algorithm is applied after analysed and verified in this paper, the unknown location of a user can be identified by using PRC information of multi-DGPS reference station. The PRC information of each GPS satellite is not varying rapidly, which makes it possible to assume that PRC information of each GPS satellite varies linearly. So, the PRC regeneration algorithm with linear interpolation can be applied to improve the accuracy of finding a user's location by using the various PRC information obtained from multi-DGPS reference station. The desirable PRC is made by the linear combination with the known position of multi-DGPS reference station and PRC values of a satellite using signals from multi-DGPS reference station. The RTK-GPS result was used as the reference. To test the performance of the linearly interpolated PRC regeneration algorithm, multi-channel DGPS beacon receiver was built to get a user's position more exactly by using PRC data of maritime DGPS reference station in RTCM format. At the end of this paper, the result of the quantitative analysis of the developed navigation algorithm performance is presented.

• Journal of the Korea Society of Computer and Information
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• v.26 no.11
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• pp.1-9
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• 2021

3D-NAND flash memory provides high capacity per unit area by stacking 2D-NAND cells having a planar structure. However, due to the nature of the lamination process, there is a problem that the frequency of error occurrence may vary depending on each layer or physical cell location. This phenomenon becomes more pronounced as the number of write/erase(P/E) operations of the flash memory increases. Most flash-based storage devices such as SSDs use ECC for error correction. Since this method provides a fixed strength of data protection for all flash memory pages, it has limitations in 3D NAND flash memory, where the error rate varies depending on the physical location. Therefore, in this paper, pages and layers with different error rates are classified into clusters through the K-means machine learning algorithm, and differentiated data protection strength is applied to each cluster. We classify pages and layers based on the number of errors measured after endurance test, where the error rate varies significantly for each page and layer, and add parity data to stripes for areas vulnerable to errors to provides differentiate data protection strength. We show the possibility that this differentiated data protection policy can contribute to the improvement of reliability and lifespan of 3D NAND flash memory compared to the protection techniques using RAID-like or ECC alone.