• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.9
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• pp.3517-3523
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• 2010

Single exposure dual X-ray imaging can be used to separate soft and dense-material images for medical and industrial applications. This study keep focusing baggage inspection system(BIS) specifically. New detector modules for single exposure dual X-ray imaging are consisted of low energy detector (LED) and high energy detector (HED). First, the optimized thickness of copper filter coupled HED to separate low energy and high energy was simulated by the given X-ray energy (140 kVp, 1 mA) using Monte Carlo simulation codes, MCNPX. So as a result of simulation, the copper filter thickness is 0.7 mm. For the design of PIN photodiode, ATLAS device simulation tool was used. 16 channels PIN photodiode of 1.5 mm ${\times}$ 3.2 mm for Dual X-ray imaging detector was fabricated in the process of ETRI. And its dark current and quantum efficiency, terminal capacitance were measured. It was proven that the Lanex Fast B coupled HED were a sufficient candidate to replace the CsI(Tl) commerced in dual X-ray system, since these give a strong signal, overcoming system noise. Finally dual X-ray image was acquired through correction of the LED X-ray Image and the HED X-ray Image.

• Bulletin of the Korean Space Science Society
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• 2011.04a
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• pp.23.1-23.1
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• 2011

The SMT is a subsystem of the UFFO (Ultra-Fast Flash Observatory) pathfinder onboard the Lomonosov spacecraft planed to be launched in November 2011. The UFFO is designed for extremely fast observation of optical afterglow of Gamma Ray Burst (GRB). This study is primarily concerned with performance measurement of the SMT optical system under the integration and test phase. SMT is a 100mm Ritchey-Chretien type telescope with a motorized slewing mirror and a $256{\times}256$ pixels Intensified Charge-Coupled Device (ICCD) of 22.2${\mu}m$ in pixel size. SMT is designed to operate over the wavelength coverage between 200 nm and 650 nm. It has 17 arcmin FOV (Field of View), providing 4arcsec in detector pixel resolution. In this study, we describe the integration and test process of the SMT optical system and interim performance measurement results with motorized slewing mirror and ICCD.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.67 no.7
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• pp.969-975
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• 2018

The purpose of this study is to develop a healthcare service based on standard protocol and information communication technology for mother's sustainable postpartum care. The developed service was consisted of a client area where mothers measure, manage and transmit their vital signs using their own smartphone and personal health devices, and a server area that manages and shares with the received mother's vital signs and the results of examination results and personal health records. The client area collects vital signs through the IEEE 11073 Personal Health Device (PHD) using the m-health application of the previous study and Continua Health alliance certified personal health devices and transfers to Health Level Seven (HL7) V2.4, Continuity of Care Record (CCR) and Continuity of Care Document (CCD). The server area consists of a mobile web that manages and shares the HL7 Fast Healthcare Interoperability Resources (FHIR)-compliant personal health records to ensure interoperability of examination results, and a mobile web where the postpartum caregiver enters and manages the results of the mother's examination results and provides it to the mother. In this way, the healthcare service of this study securing continued exchanges between the mother and postpartum caregiver improves the quality of life of the mother not only to satisfy the needs of the mother who was discharged but also through self-management and postpartum. In the future, we will conduct a study applying mothers and postpartum caregiver after approval of a clinical trail at a university hospital to evaluate developed healthcare services.

• Journal of Communications and Networks
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• v.18 no.5
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• pp.837-845
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• 2016

Providing a customer with tailored location-based services (LBSs) is a fundamental problem. For location-estimation techniques with radio-based measurements, LBS applications are widely available for mobile devices (MDs), such as smartphones, enabling users to run multi-task applications. LBS information not only enables obtaining the current location of an MD but also provides real-time push-pull communication service. For indoor environments, localization technologies based on radio frequency (RF) pattern-matching approaches are accurate and commonly used. However, to survey radio information for pattern-matching approaches, a considerable amount of time and work is spent in indoor environments. Consequently, in order to reduce the system-deployment cost and computing complexity, this article proposes an indoor positioning approach, which involves using Asus Xtion to facilitate capturing RF signals during an offline site survey. The depth information obtained using Asus Xtion is utilized to estimate the locations and predict the received signal strength (RF information) at uncertain locations. The proposed approach effectively reduces not only the time and work costs but also the computing complexity involved in determining the orientation and RF during the online positioning phase by estimating the user's location by using a smartphone. The experimental results demonstrated that more than 78% of time was saved, and the number of samples acquired using the proposed method during the offline phase was twice as much as that acquired using the conventional method. For the online phase, the location estimates have error distances of less than 2.67 m. Therefore, the proposed approach is beneficial for use in various LBS applications.

• Journal of Power Electronics
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• v.18 no.4
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• pp.1278-1292
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• 2018

Inductive power transfer (IPT) technology allows for charging of electric vehicles with security, convenience and efficiency. However, the IPT system performance is mainly affected by the magnetic coupling structure which is largely determined by the coupling coefficient. In order to get this applied to electric vehicle charging systems, the power pads should be able to transmit stronger power and be able to better sustain various forms of deviations in terms of vertical, horizontal direction and center rotation. Thus, a novel cross-shaped magnetic coupling structure for IPT charging systems is proposed. Then an optimal cross-shaped magnetic coupling structure by 3-D finite-element analysis software is obtained. At marking locations with average parking capacity and no electronic device support, a prototype of a 720*720mm cross-shaped pad is made to transmit 5kW power at a 200mm air gap, providing a $1.54m^2$ full-power free charging zone. Finally, the leakage magnetic flux density is measured. It indicates that the proposed cross-shaped pad can meet the requirements of the International Commission on Non-Ionizing Radiation Protection (ICNIRP) according to the Australian Radiation Protection and Nuclear Safety Agency (ARPANSA).

• Journal of Biomedical Engineering Research
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• v.31 no.2
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• pp.123-128
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• 2010

The thermometers is widely used in diagnostic medical devices, and the safety and accurate performance of these devices are important in the diagnosis and monitoring of personal health. Especially, the accuracy of infra-red thermometer is highly emphasized. Here two typical thermometers are utilized for this purpose: the electronic thermometers measure body temperature by contacting to subject while infra-red thermometers measure by no contacting to subject. Therefore, the evaluating items of each thermometer are different, and the standard for each temperature is highly needed. But, there have been no international standards of each thermometer such as IEC. In this paper, we developed the standards of electronic and infra-red thermometer based on national standards such as KS, ASTM, EN, JIS and FDA guidance. The new standards focused on the safety and suitable performance for health care. This standards were applied to enact and revise the electronic medical device standards. So it can be applied to evaluate the safety and performance on technical file review. We predict that this standard will improve the quality of diagnostic medical devices (thermometers) and increase the international competitive power of domestic product.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.10
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• pp.1492-1497
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• 2005

The goal of the trial was to evaluate the effects of ractopamine (20 ppm in the ration) given pregnant sows during three different pregnancy stages (T1: 25 to 50 d; T2: 50 to 80 d; T3: 25 to 80 d of gestation, and T4: control-no ractopamine) on fetal muscle development (through counts of the number of fibers of the semitendinosus muscle), on the growth and carcass characteristics of the progeny. Forty eight weaned piglets (12 per treatment) were assessed for number of muscle fibers, while performance and carcass characteristics were evaluated on a separate 48 animals (12 per treatment) grown to 100 kg. Animals produced by sows treated from 25 to 50 d of pregnancy (T1) resulted in non-significant increase of 6.85% in the number of muscle fibers in the semitendinosus muscle when compared to animals from the control group. Performance results were significantly different (p<0.05), and animals produced by sows from the T1 group gained more weight during the growth I stage (25 to 50 kg) and during the total period (6 to 100 kg) (991 vs. 903 grams, and 844 vs. 772 grams, respectively) when compared to controls. For carcass characteristics, results showed that animals produced by the T1 group of sows were heavier at slaughter (p<0.05) when compared to the controls (T4) (100.17 vs. 93.09 kg). There was a positive correlation between number of muscle fibers and bodyweights, carcass weights, Longissimus dorsi muscle depth and dressing out (0.80, 0.86, 0.67, and 0.50, respectively). Sows treated with ractopamine between 25 to 50 d of pregnancy produced piglets that performed better and had superior carcass characteristics than those produced by untreated sows. The ractopamine used for pregnancy sows (25 to 50 d) can be indicated as a device to increase the progeny performance.

• Journal of Satellite, Information and Communications
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• v.10 no.2
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• pp.24-29
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• 2015

Recently, with developments of various networks, devices and various services, energy efficiency has become one of the most crucial issues with respect to sustainability of mobile devices. For connecting to networks seamlessly to offer services, a scenario of RF energy harvesting which supplies energy to wireless devices with RF signals is assumed. To increase the efficiency of RF energy harvesting, this paper proposes a RF energy harvesting algorithm which is based upon a frequency selective fading map. Through the algorithm, a receiver of mobile device can get fading information at each frequency and select a frequency which has the best quality. At the end, the simulation result demonstrates its superiority by showing a 4.45dB improvement in comparison to a deep fading frequency point.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.21 no.1
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• pp.79-84
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• 2008

We are developing a small-sized high temperature superconducting magnetic energy storage (HTS-SMES) magnet with the nominal storage capacity of 600 kJ, which provides electric power with high quality to sensitive electric loads. Critical current and N-value of a high temperature superconductor with large current, which was selected for the development of the 600 kJ HTS-SMES magnet, were investigated in various oblique external magnetic fields. Based on the critical current and N-value measured for the short sample conductor, we discussed the DC V - I characteristic of a model coil fabricated with the same conductor of 500 m. The results show that the measured critical current and N-value of the conductor for parallel field are constant in external magnetic fields less than about 0.2 T. However, for oblique fields, its critical current and N -value abruptly decrease in all external magnetic fields. Moreover, the measured critical current of the model coil well agrees with the numerically calculated one based on the DC V - I characteristic measured for the short sample conductor. This suggest that losses and critical currents for an HTS-SMES magnet made up of a high temperature superconductor with anisotropic characteristic are predictable from the data of a short sample conductor.

• Korean Journal of Optics and Photonics
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• v.8 no.2
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• pp.169-173
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• 1997

Most conventional lithography systems have been oriented to fabricate electronic devices. Therefore, it is not so easy to fabricate large aspect ratios of waveguide patterns with those systems. When considering costs and efficiencies, a laser lithography system provides number of benefit in realizing waveguide patterns. However, because the conventional laser lithography system could make only positive tone masks, it is inconvenient in determining the direction of the waveguide. A simple and reliable technique to produce negative tone masks was developed by using the laser beam writing. This technique was not sensitive to environmental situations such as dust, vibration, intensity variation. Making use of the technique a variety of device patterns such as Y-branch, directional coupler, and highly smooth S-shape bend could be successfully fabricated with a good contrast.