• Journal of IKEEE
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• v.27 no.1
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• pp.109-115
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• 2023

In this paper, we design and implement an Ultra-Wide Band (UWB, 3.1~10.6 GHz) antenna with 5G mobile communication (3.42~3.70 GHz) and Wireless Local Area Network (WLAN, 5.15~5.825 GHz) bands rejection characteristics. The proposed antenna consists of a planar radiation patch with two slots. The upper slot contributes to reject 5G mobile communication band and the lower slot contributes to reject WLAN band. The Voltage Standing Wave Ratio (VSWR) values of the proposed antenna show good performances in whole UWB band except for rejection bands based on VSWR 2.0. The proposed UWB antenna was simulated using High Frequency Struture Simulator (HFSS) by Ansoft. The simulated antenna showed dual rejection bands of 3.31~3.92 GHz and 5.04~5.90 GHz in UWB band, and measured antenna showed dual rejection bands of 3.35~3.97 GHz and 5.06~5.97 GHz. The largest VSWR values measured at each rejection band are 13.60 at 3.64 GHz and 10.25 at 5.52 GHz. The measured maximum gain is 5.31 dBi at 10.00 GHz. The lowest gains for the measured antenna at rejection bands are -8.73 dBi at 3.70 GHz and -4.36 dBi at 5.56 GHz.

• Journal of applied mathematics & informatics
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• v.40 no.1_2
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• pp.47-59
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• 2022

This paper concerns the problem of simultaneous fault detection and disturbance reject control(SFDDRC) for a class of linear time-invariant system. In the framework of fault detection, residual generators are required to be robust to disturbances existing in the system. Different from most of the existing simultaneous fault and control(SFDC) methods, SFDDRC rejects the influences of disturbances on residual generators by disturbance observer-based control(DOBC). This not only effectively improves the accuracy of fault detection, but also solves the problem that most of the existing SFDC methods require that the disturbance must be bounded. Finally, a numerical example is given to verify the validity of the method.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.11 no.2
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• pp.240-251
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• 2000

This study was a preliminary study on the adolescent psychiatric patients that show the characteristics of peer group neglect or rejection. We divided the adolescent psychiatric patients(n=25) into neglect-reject group(n=15) and non-neglect group(n=10). Each patient answered 8 scales and several questions about general relationships with friends. And, both the score of each 8 scales and answer about qusetions were examined. Lastly, records of 5 cases from neglect-reject group were analyzed. The depression dimension score of SCL-90-R, anxiety dimension score of SCL-9O-R, paranoid dimension score of SCL-90-R, interaction anxiousness scale(IAS) score were significantly different between 2 groups. On the result of case analysis about 5 patients of neglect-reject group, the adolescent psychiatric patients had a tendency to be rejected or neglected in case of having developmental problems(for example, language development or cognitive impairment).

• Korean Chemical Engineering Research
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• v.55 no.6
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• pp.816-821
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• 2017

An integrated slow mixing/sedimentation and net fit fiber filtration system has been developed to reduce the high concentrations of suspended solid (SS) and total phosphorus (T-P) in the reject water from sewage/wastewater. A filtration device used in this experiment consists of coagulation, in-line mixing, air injection, slow mixing/sedimentation, and filtration processes. The performance test using this device was carried out with six operational modes for reject water from sewage treatment plant. Experimental conditions used were 16.7, 33.3, 41.7 and 50.0 ton/day of flow rate and 2~4 of Al/P molar ratio. By injection of coagulant in each operational mode, the high removal efficiencies of SS and T-P were obtained, but continuous operation time was decreased to 7.8~11.4 min in most modes. However, when the Mode 5 of the developed filtration device was applied, the continuous operation time was maintained up to 88.2 min. Also, it was found that the continuous operation time in the Mode 5 using the developed system was increased from 8 to 11.3 times longer than those in other modes. Backwashing flow rate was also very low at 5.4% of total filtered water. Therefore, it can be concluded that the Mode 5 of the developed filtration system was the most efficient treatment method for the removal of high concentrations of SS and T-P.

• The Journal of the Acoustical Society of Korea
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• v.20 no.2
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• pp.27-34
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• 2001

Utterance verification is used in variable vocabulary word recognition to reject the word that does not belong to in-vocabulary word or does not belong to correctly recognized word. Utterance verification is an important technology to design a user-friendly speech recognition system. We propose a new utterance verification algorithm for no-training utterance verification system based on the minimum verification error. First, using PBW (Phonetically Balanced Words) DB (445 words), we create no-training anti-phoneme models which include many PLUs(Phoneme Like Units), so anti-phoneme models have the minimum verification error. Then, for OOV (Out-Of-Vocabulary) rejection, the phoneme-based confidence measure which uses the likelihood between phoneme model (null hypothesis) and anti-phoneme model (alternative hypothesis) is normalized by null hypothesis, so the phoneme-based confidence measure tends to be more robust to OOV rejection. And, the word-based confidence measure which uses the phoneme-based confidence measure has been shown to provide improved detection of near-misses in speech recognition as well as better discrimination between in-vocabularys and OOVs. Using our proposed anti-model and confidence measure, we achieve significant performance improvement; CA (Correctly Accept for In-Vocabulary) is about 89％, and CR (Correctly Reject for OOV) is about 90％, improving about 15-21％ in ERR (Error Reduction Rate).

• Journal of information and communication convergence engineering
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• v.9 no.3
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• pp.256-259
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• 2011

In this article, new microstrip slow-wave bandpass filters using open loop resonator loaded with inter-digital capacitive fingers is proposed. The filter features not only compact in size, but also exhibits spurious stop-band rejection. Filters of this type with elliptic function and Chebyshev response are demonstrated. There is good agreement between experimental and full-wave electromagnetic (EM) simulation results.

• Journal of Environmental Impact Assessment
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• v.3 no.1
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• pp.31-41
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• 1994

The choice of economic development over environmental protection has been used to explain the decline in the quality of the environment in developing countries. The authors reject this explanation and propose a theory of negligence to explain this decline. They point to the advantages of environmental impact assessments in dealing with the problem of negligence and presents case studies from four countries. Organizational models for Environmental Impact Assessments in Developing Countries are proposed as useful policy measures.

• Proceedings of the KIEE Conference
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• 1988.11a
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• pp.28-31
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• 1988

This paper proposes a new linear adaptive position controller of DC servo motor. The proposed method can improve the drive performance and rapidly reject the state error caused by both parameter variations and force disturbance. The structure of this adaptive control method is based multiloop feedback control and model reference control. Simulation results are presented to verify the improved response when parameter variations and load disturbance give relatively significant effects to the servo system.

• Proceedings of the KIEE Conference
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• 1988.11a
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• pp.430-433
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• 1988

An adaptive control system for D.C servo drive is developed via minimum variance control theory. The problem of designing this controller under varying load conditions is discussed. A robust self tuning controller that can track a constant reference and reject constant load disturbance is developed. Simulation study shows that the controller has excellent adaptation, capability as well as transient recovery under load changes.

• International Journal of Reliability and Applications
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• v.6 no.1
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• pp.31-39
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• 2005

An economic life test sampling plan for products with exponential lifetime distribution is developed. To reduce test time, a test plan with curtailed Type II censoring is considered. A cost model is constructed which involves three cost components; test cost, accept cost, and reject cost. Determination of optimal plan minimizing the expected average cost per lot is discussed with a constraint related to consumer's risk. Some numerical examples are provided.