• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2001.09a
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• pp.184-187
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• 2001

This study presents procedure and analysis method for not well known slug interference tests. Results of the slug interference tests were compared with those of pumping and recovery tests and conventional slug tests.

• Journal of computational fluids engineering
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• v.1 no.1
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• pp.134-141
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• 1996

Wall interference is one of the major obstacles to increase the model size and data accuracy. There have been many treatments for wall interference including interference correction and adaptive wall test section. Recently, two-flexible-walled adaptive wall test section is concluded adequate for three-dimensional test. But proper location of target line and pressure holes are critical to its success. In this study, a new adaptive algorithm which dispenses target line and dependency of pressure hole distribution is suggested. The wind tunnel and free air tests are simulated by the numerical computation of Euler equations. The optimum wall shape is achieved by two variable optimization which is composed of two base streamlines. The wall interference is reduced well in the optimized result which is not sensitive to the base streamlines.

• Journal of the Korean Institute of Telematics and Electronics
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• v.26 no.3
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• pp.40-49
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• 1989

A variable-state block interference channel model is presented which matches asynchronous multiple-access slow frequency-hopped spread-spectrum systems which suffer from bursts of interference of variable duration. For variable-state block interference channels test pattern techniques combined with interleaving are presented from which the decoder obtain side information about channel states. By examining test patterns the decoder estimates which parts of data blocks are affected by interference and regards the parts of blocks affected by interference as erasures. Since the presence of test patterns reduces the number of bits for data transmission, test patterns are not useful for variable-state block interference channels for small hit probability, It is shown that test patterns increase the capacities of variable-state block interference channels for large hit probability. It is also shown that test patterns provide a almost full side information about channel states for certain values of parameters.

• Journal of Korean Academic Society of Home Health Care Nursing
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• v.24 no.2
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• pp.189-199
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• 2017

Purpose: This study aimed to investigate the effects of foot bath therapy on the symptom intensity, distress, and interference with usual activities due to chemotherapy-induced peripheral neuropathy (CIPN) in patients with metastatic and recurrent cancer. Methods: Foot bath therapy was administered to the experimental group for >8 sessions in 2 weeks, and the chemotherapy-induced peripheral neuropathy assessment tool (CIPNAT) was used to measure its effects on the symptom intensity, distress, and interference with usual activities due to CIPN. SPSS was used to perform data analyses including descriptive statistics, chi-square test, Fisher's exact test, t-test, paired t-test, and repeated measures ANCOVA. Results: A statistically significant difference in the variation of the symptom intensity, distress, and interference with usual activities due to CIPN was observed between the two groups; however, a statistically insignificant difference was observed between the groups and time of interaction. Conclusion: Foot bath therapy can be used as a simple and effective clinical or home care nursing intervention to improve the symptom intensity, distress and interference with usual activities due to CIPN.

• Aerospace Engineering and Technology
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• v.2 no.1
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• pp.153-163
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• 2003

Electronic equipments and make other electronic systems to operate abnormally by means of electromagnetic interference, or can operate abnormally themselves by electromagnetic interference of other electronic systems. Therefore, electronic equipments are required to reduce their electromagnetic interference as small as for other systems to operate properly and operate properly within electromagnetic interference from other electronic systems. In order to prove that electronic equipments meet such requirements, they should undergo electromagnetic environmental test. In this study, we introduce electromagnetic environmental requirements, test procedures and test results of gimbal engine actuation system of KSR-III.

• Journal of Auto-vehicle Safety Association
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• v.8 no.2
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• pp.30-36
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• 2016

According to revolutionary developments in automobile technologies, various electronically controlled components of vehicles are rapidly increasing. A variety of advanced vehicles (hybrid vehicle, hydrogen fuel-cell vehicle, electric vehicle, etc.) using electrical energy source are increasing, too. The electromagnetic compatibility is getting more important for development of a vehicle because those advanced vehicles are equipped with more new electronic systems. In general, electromagnetic compatibility tests consist of an electromagnetic interference (EMI) test and an electromagnetic susceptibility (EMS) test. In this paper, in order to investigate the electromagnetic interference in the cabin of vehicle by various electric and electronic components of vehicles, a series of narrowband electromagnetic emission tests are conducted. For comparison, the several digital home appliances (smartphone under charging, laptop compuer and digital camera), which are used a lot in daily lives, are tested.

• International Journal of Internet, Broadcasting and Communication
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• v.15 no.4
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• pp.107-114
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• 2023

In this paper, the results of experiments conducted in indoor wired and outdoor wireless environments to reduce the interference impact of 5G mobile communication on fixed satellite services using RF Interference Reduction Module (IRM) are presented. Test results for interference signals with a 100MHz bandwidth in a wired environment demonstrate that RF IRM can reduce interference by more than 20dB in a 100MHz bandwidth. The performance of RF IRM was also tested in the S-band wireless environments. In the S-band wireless environments with interference signals having a 20MHz bandwidth, RF IRM exhibits interference reduction performance of 12-15dB, for signals with a 50MHz bandwidth, it shows 10-12dB interference reduction, and for signals with a 100MHz bandwidth, it demonstrates 5-10dB interference reduction. This paper shows that RF IRM can be used not only within transceivers but also in wireless environments to mitigate interference.

• Journal of Positioning, Navigation, and Timing
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• v.4 no.1
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• pp.9-16
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• 2015

The applications of Global Navigation Satellite System (GNSS) receivers are becoming wider in various commercial and military systems including even small weapon systems such as artillery shells. The precision-guided munitions such as Small Diameter Bomb (SDB) of United States can be used for pinpoint strike by acquiring and tracking GNSS signals in high mobility situation. In this paper, a small GNSS receiver with embedded interference suppression capability working under high dynamic stress is developed which is applicable to the various weapon systems and can be used in other several harsh environments. It applies a kind of matched filter and multiple correlator schemes for fast signal acquisition and tracking of even weak signals and frequency domain signal processing method to eliminate the narrowband interference. To evaluate the performance of the developed GNSS receiver, the test scenario of high mobility and interference environment with the GNSS simulator and signal generator is devised. Then, the signal acquisition time, navigation accuracy, sensitivity, and interference suppression performances under high dynamic operation are evaluated. And the comparison test with the commercial GNSS receiver which has high sensitivity is made under the same test condition.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.12 no.2
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• pp.43-52
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• 2012

This paper presents and analyzes laboratory test results of Interference Cancellation Digital On Channel Regenerative Repeater(IC-DOCR) to broadcast digital television signals in the Advanced Television Systems Committee(ATSC) transmission systems using single frequency networks(SFN). IC-DOCR laboratory test is classified to receiver test, transmitter test, and feedback interference cancellation test. The receiver part includes random noise, single echo, multi-path ensembles, and adjacent channel interference test. The transmitter part includes out-of channel emission, equality of transmitting signal, and phase noise test. By the laboratory test, the receiver part of the IC-DOCR eliminates 28dB of feedback signal higher than the received signal and has 17.8dB at TOV(Threshold Of Visibility) under random noise environment. Also, the transmitter part satisfies the specification of US FCC(Federal Communications Commission) as well as maintains good output signal quality for guaranteeing more than SNR 30dB.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2002.05a
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• pp.22-26
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• 2002

The goal of this study is to replace the current forward 2-piece propeller shaft of 8 ton large truck made of steel with 1-piece composite propeller shaft. A low cost Glass/Epoxy composite propeller shafts were successfully developed, which satisfy requirements such as the capacity of static torque transfer, fatigue strength and bending natural frequency. Devising secure joining method of a composite tube and metal yoke was the most critical issue in successful development of a high torque composite propeller shaft. In this study, joining method using thermal interference fit was adopted for composite to metal joint. Optimum conditions of heating temperature and interference level of thermal interference fit were determined from thermal stress analysis using 3D finite element method. Static torsion test, fatigue test, RPM and balance test were performed to verify the design.