• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.5
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• pp.792-797
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• 2006

In this paper, an internal integrated microstrop patch for PCS handset is designed. To increase the bandwidth of microstrip patch antenna, a configuration of stacked type using parasitic element is used. Furthermore, to reduce the size of microstirip patch antenna, the main radiator in the substrate is shorted to the ground plane using five shorting-posts while three parasitic elements on the superstrate are also shorted to the ground plane using two shorting-posts respectively. The antenna bandwidth and radiation characteristics are calculated by HFSS 7.0 software, and compared with the experimental results. Experimental results show that the return loss is less than -10dB over the band of 1766MHz to 1900 MHz(134MHz) and the size of the fabricated microstrip patch antenna are $23\times20\times6.35mm$.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.10
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• pp.2269-2274
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• 2015

In this paper, the reduced size in horizontal sizes of the narrow band pass filter (BPF) with λg/4 short stub using S shaped folded coupling structure is presented. This BPF with narrow bandwidth show flexible bandwidth with variation of the position of the stubs using the Qe(external quality factor) without changing the impedance value. On the other hand, by replacing the horizontal quarter-wavelength transmission lines with the equivalent S shaped coupled line, the BPF with reduced the size of horizontal can be realized. The proposed BPF shows the insertion loss of 1.46 dB and the return loss of 16.5 dB with bandwidth of 3.4 % at the center frequency of 5.8 GHz, respectively.

• The Journal of the Korea institute of electronic communication sciences
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• v.16 no.2
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• pp.287-292
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• 2021

In this paper, we propose an efficient CNN application method by analyzing the effect of activation function on the failure diagnosis of the inductive motor stator. Generally, the main purpose of the inductive motor stator failure diagnosis is to prevent the failure by rapidly diagnosing the minute turn short. In the application of activation function, experiments show that the Sigmoid function is 23.23% more useful in accuracy of diagnosis than the ReLu function, although it is shown that ReLu has superiority in overall fixer failure in utilizing the activation function.

• Fire Science and Engineering
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• v.16 no.3
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• pp.8-11
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• 2002

Recently, the spark and the overheat due to in the failure of pressure contacts on connecting points and the momentary short circuit have been the major causes of electrical fire because these may cause the deposition and the graphite of insulating materials in electrical wiring system. Also, because in these cases the current is a surge one, the losses and faults of a communication, a home appliances, a computer and a measuring instrument may occur. Especially, in such cases, we are very difficult to detect the failure of pressure contacts on connecting points and the momentary short circuit. In this paper, we have developed an auxiliary control device, the electrical fire prevention control device(EFPCD), of an earth leakage breaker(ELB). And we can pre-vent the electrical fire caused by the spark and the overheat occurring in the failure of pressure contacts in connecting points and the momentary short circuit with the EFPCD.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2003.05a
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• pp.530-533
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• 2003

본 논문에서는 2GHz의 패치폭과 그라운드면의 폭이 같은 QMSA의 구조를 설계 및 제작하였고, QMSA의 구조를 변형하여 용량을 장하한 QMSA와 기생소자를 갖는 QMSA를 제안하였다. QMSA의 구조는 한 쪽 끝이 전기적으로 단락된 λ/4의 구조로 설계하였으며, 용량을 갖는 QMSA는 상측 평행 평판과 하측 평행 평판 사이의 용량을 구성시킴으로써 리턴로스와 공진주파수의 변화를 비교 평가하였다. 또한, 기생소자를 갖는 QMSA의 구조는 상측 평행 평판위에 기생소자를 가변함으로써 안테나를 소형화할 수 있었다. QMSA는 2GHz의 중심주파수를 갖고 2%의 대역폭을 갖으며, 용량의 변화와 기생소자의 길이에 따라 공진주파수의 변화를 보였다.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 2004.07a
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• pp.437-437
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• 2004

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2000.05a
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• pp.115-118
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• 2000

본 논문에서는 4 개의 다이폴 소자로 구성한 4 섹터 지향성 절환 원형 배열 다이폴 안테나의 기본 특성을 검토하고 있다. 안테나의 방사 지향성이 순차적으로 4 섹터 절환이 가능하도록 하기 위해 급전 및 무급전 소자를 적절히 이용하고 있으며, 무급전 소자의 유도 전류에 의한 원형 배열 안테나의 특성 개선을 위해 급전 소자를 제외한 나머지 소자들을 단락 또는 개방시켜 방사 지향성 및 이득 특성 등을 계산하고 있다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2002.05a
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• pp.219-222
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• 2002

본 논문에서는 기존의 QMSA에 비해 안테나 전체 길이를 소형화함은 물론 전기력선이 미치는 범위가 제한받지 않도록 그라운드 판을 접어 올려 방사 패치와 단락시키고 급전점의 위치를 조절하여 더욱 소형화할 수 있는 QMSA를 제안하고 설계 제작했다. 그리고 안테나에 잡음지수가 낮아지도록 LNA를 연결하여 본래의 QMSA에 비해 이득이 높고, 잡음에 강한 능동안테나를 설계·제작하였다. QMSA와 LNA는 1.8 ㎓대로 설계하여 각각의 이득과 안정도를 확인하고, 안테나와 증폭기가 통일한 평면상에 구성된 능동안테나와 QMSA를 비교 평가하였다.

• The Journal of the Korea institute of electronic communication sciences
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• v.10 no.4
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• pp.433-439
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• 2015

Enclosures for CCTV internal short circuit are prevented due to wetting to maintain a constant humidity and temperature, to avoid condensation due to temperature difference, a constant temperature and humidity requirements of the equipment, such as high-temperature resistant and a constant temperature of the structure, degree of energy utilization is optimized for developing this corresponding housing automatic control system and humidity is required. Device being an expensive imaging equipment in side of the enclosure according to the temperature conversion from a hazard protection, there is a need for a constant temperature and humidity control apparatus that can prevent a short-circuit failure. This is a system in which the accessory device is absolutely required for the storage and transmission of an image in recording reliability and field conditions.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.24 no.12A
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• pp.2008-2014
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• 1999

IDDQ testing is an effective testing method to detect various physical defects occurred in CMOS circuits. In this paper, we consider intra-gate shorts within circuit under test and implement IDDQ test pattern generator to find test patterns which detect considered defects. In order to generate test patterns, gate test vectors which detect all intra-gate shorts have to be found by type of gates. Random test sets of 10,000 patterns are applied to circuit under test. If an applied pattern generates a required test vector of any gate, the pattern is saved as an available test pattern. When applied patterns generate all test vectors of all gats or 10,000 patterns are applied to circuit under test, procedure of test pattern generation is terminated. Experimental results for ISCAS'85 bench mark circuits show that its efficiency is more enhanced than that obtained by previously proposed methods.