• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2015.05a
• /
• pp.363-364
• /
• 2015

On the area which is restricted an unauthorized WiFi service, mobile WiFi hotspot causes security problems like leaking and gathering internal data. In this paper, we modify a wireless lan driver and implement a detector that periodically scans the wireless channels.

• Proceedings of the KAIS Fall Conference
• /
• 2008.05a
• /
• pp.189-191
• /
• 2008

본 논문에서는 스캔 체인의 레이아웃 거리를 고려한 효율적인 Test Wrapper 설계 방식을 제안한다. SoC내의 스캔체인들을 테스트 하기 위해서는 외부 TAM line에 각 스캔체인들을 할당해야 한다. IP 내에 존재하는 스캔체인들은 스캔체인간 레이아웃 거리를 갖게 되며 이 거리가 클럭주기를 넘어가는 경우 체인의 타이밍 위반(Timing violation)이 발생될 수 있다. 본 논문에서는 타이밍 위반이 발생하지 않도록 체인간 거리를 고려하여 스캔체인을 할당하는 새로운 test wrapper 설계 방식을 제안하였다.

• Proceedings of the Korea Society for Industrial Systems Conference
• /
• 1998.10a
• /
• pp.861-866
• /
• 1998

본 논문은 프로우브 급전한 주기적인 위상 배열 마이크로스트립 안테나의 계산된 결과를 제시한다. 수치적인 마들은 엄밀한 그린 함수와 캘러킨 (Galerkin)해에 근거를 둔다. 임의의면(plane)에서의 입력 임피던스를 스캔 각도에 따라 계산하여 반사계수를 구하고 유전체의 유전율과 두께가 위상 배열 안테나에 미치는 영향을 제시한다. 표면파에 의한 스캔 블라인드 현상을 설명하고 유전체의 두께에 따른 E-면과 H-면에서의 입력 임피던스 대역폭을 계산한다.

• The Korean Journal of Nuclear Medicine
• /
• v.25 no.2
• /
• pp.211-218
• /
• 1991

1983년 1월부터 1991년 2월까지 서울대학교 병원에서 진단된 위 암환자를 대상으로 시행한 359예의 골스캔을 후향적으로 재검토하여 골전이 빈도와 양상을 관찰하였으며 환자들의 의무기록을 검토하여 위암의 임상상과 비교하였다. 그 결과는 다음과 같았다. 1) 359예의 골스캔 중에서 골전이에 부합되는 이상소견은 167예(46.5%)이었다. 2) 관찰된 167예의 이상소견 빈도는 척추(66%)에 가장 많이 관찰되었고, 늑골(58%), 골반부(43%), 대퇴골(31%), 두개골(22%)순이었다. 3) 척추전이에서 흉추(65.6%)와 요추(64.5%)의 전이빈도는 거의 비슷하였고, 경추(23.6%)는 낮았다. 4) 골전이 빈도는 임상적 병기 3기 환자에서 진단후 1년 이내에 급격히 증가되었고 그 이후는 증가되지 않았다. 5) 골전이는 임상적 병기가 증가됨에 따라 증가되었으나, 조직학적 세포형태와는 무관하였다. 6) 혈청 alkaline phosphatase 치와 골스캔 상의 골전이 유무와 통제적으로 유의 한 상관관계가 관찰되었다. 이상의 결과로 위암환자의 상당 수에서 골전이가 진단되었으며 위 암환자, 특히 진행암 환자에서 골전이에 대한 주기적인 추적 검사가 필요할 것으로 생각된다.

• Journal of the Korean Society of Radiology
• /
• v.15 no.3
• /
• pp.293-299
• /
• 2021

In order to reduce the irresistible radiation exposure of patients who perform periodic examinations using a CT among various scan parameters a method to reduce patient dose was investigated through changes in the tube voltage close to X-ray penetrating power. As a result of the experiment 100 kVp was applied instead of 120 kVp which is commonly used in clinical practice and CTDI decreased by about 41% during scan. In addition the degree of change in image quality was measured as 1046.1±3.7 HU for CT value and 71.4±7.9 for Pixel value and statistical analysis showed no significant difference (0.05

• The Korean Journal of Nuclear Medicine
• /
• v.31 no.3
• /
• pp.346-355
• /
• 1997

To evaluate the utility of I-131, T1-201 scintigraphy, and serum thyroglobulin(Tg) in the follow-up of differentiated thyroid cancer, we compared retrospectively the data from 33 patients who underwent total or subtotal thyroidectomy. I-131 scintigraphy was performed after optimal endogenous TSH stimulation ($TSH>50{\mu}U/ml$). Total 41 cases of I-131 and T1-201 scintigraphy pairs were examined. Concomitant serum thyroglobulin levels were measured for 41 pairs of scan. Tg-off levels(that measured after discontinuation of the thyroid hormone) higher than 40ng/m1 were considered positive, and Tg-on levels(that measured during the thyroid hormone replacement) higher than 5ng/ml were considered positive. The concordance rates between I-131 therapeutic scintigraphy and T1-201 scintigraphy was 48% in the 38 case of total scan pairs(59% in the 17 cases of postoperative preablation group, and 38% in the 21 cases of postoperative postablation group). Of 17 studies before the I-131 ablation therapy(preablation group), 7 showed positive I-131 therapeutic scintigraphy despite of negative T1-201 scintigraphy. Among patients with negative I-131 therapeutic scintigraphy, no patients had abnormal T1-201 uptake. However, of 21 studies which were done after radioiodine therapy(postablation group) 6 had abnormal uptake on T1-201 scintigraphy which were not seen on I-131 therapeutic scintigraphy, and Tg-off levels also elevated in this 4 of 6 cases. As a result, I-131 therapeutic scintigraphy showed highest positive rate at postoperative preablation follow-up study in differentiated thyroid cancer patients. T1-201 scintigraphy may be useful in postablation studies, and the use of the combined modalities(T1-201 and Tg levels) provides a higher diagnostic yield.

• Convergence Security Journal
• /
• v.7 no.1
• /
• pp.63-75
• /
• 2007

Most of computer systems to be connected to network have been exposed to some network attacks and became to targets of system attack. System managers have established the IDS to prevent the system attacks over network. The previous IDS have decided intrusions detecting the requested connection packets more than critical values in order to detect attacks. This techniques have False Positive possibilities and have difficulties to detect the slow scan increasing the time between sending scan probes and the coordinated scan originating from multiple hosts. We propose the port scan detection rules detecting the RST/ACK flag packets to request some abnormal connections and design the data structures capturing some of packets. This proposed system is decreased a False Positive possibility and can detect the slow scan, because a few data can be maintained for long times. This system can also detect the coordinated scan effectively detecting the RST/ACK flag packets to be occurred the target system.

• Proceedings of the Korea Contents Association Conference
• /
• 2010.05a
• /
• pp.272-273
• /
• 2010

The method of interrupt control is attempted to recognize the button-pushed result from a keyboard scan through control of 30ms appropriate period instead of key scan control method for a microprocessor system. This experimental study shows the reduced processing load of a microprocessor and prevention of the error by an algorithm when the keyboard buttons are both pushed at the same time as we recognize the result of a keyboard scanning by an interrupt method. In addition, an algorithm is provided to recognize the result of scanning by C programming as the keyboard button of a microprocessor system is pushed.

• Journal of Korea Multimedia Society
• /
• v.15 no.11
• /
• pp.1358-1368
• /
• 2012

A tag sequence estimation scheme is to estimate the physical sequence of passive RFID tags that are linearly spread using the movement of a RFID reader. Since RFID readers communicate with the passive tags by very weak radio waves, scanning passive tags are unstable. In this paper, we applied round-trip scanning of a reader to enhance the tag sequence estimation. Proposed scheme first determines the turning point of the reader movement, and then estimates the sequence of the tags using the tag sets scanned in each read cycles. Test experiments show that the proposed scheme can improve the estimation accuracy.

• The Journal of Korean Academy of Prosthodontics
• /
• v.57 no.4
• /
• pp.432-438
• /
• 2019

Accurate impression taking for the success of implant prosthesis is a very important process. Methods of taking implant impression include the conventional method using impression coping and impression material, and the digital method using an intraoral scanner and scanbody. However, the impression coping or the scanbody must install after remove healing abutment. Because of this, the dentist must repeat the process of removing and installing the healing abutment, the impression coping or the scanbody several times. In addition, the impression coping or the scanbody rises higher than the occlusal surface, so the patient has the inconvenience of constantly maintaining the open state. Recently, a scannable healing abutment, which can be scanned by a intraoral scanner directly, without the need to remove the healing abutment by applying a scannable part of the scanbody to the healing abutment, was introduced. We present a case of single posterior implant prosthesis using a scannable healing abutment.