• Geomechanics and Engineering
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• 제38권2호
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• pp.191-203
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• 2024

One of the issues with clayey soils, particularly those with significant quantities of organic matter, is the creep settling problem. Clay soils can be strengthened using a variety of techniques, one of which is the use of stone columns. Prior research involved foundation loading when the soil beds were ready and confined in one-dimensional consolidation chambers. In this study, a particular methodology is used to get around the model's frictional resistance issue. Initially, specimens were prepared via static compaction, and they were then re-consolidated inside a sizable triaxial cell while under isotropic pressure. With this configuration, the confining pressure can be adjusted, the pore water pressure beneath the foundation can be measured, and the spacemen's lateral border may be freely moved. This paper's important conclusions include the observation that secondary settlement declines with area replacement ratio. Because of the composite ground's increasing stiffness, the length to diameter ratio (l/d) and the stone column to sample height ratio (Hc/Hs) both increase. The degree of improvement varies from 12.4 to 55% according to area replacement ratio and (l/d) ratio.

• 제어로봇시스템학회논문지
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• 제22권9호
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• pp.716-722
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• 2016

Coordinate estimation is an essential function for autonomous navigation of a mobile robot. The optical mouse sensor is convenient and cost-effective for the coordinate estimation problem. It is possible to overcome the position estimation error caused by the slip and the model mismatch of robot's motion equation using the optical mouse sensor. One of the simple methods for the position estimation using the optical mouse sensor is integration of the velocity data from the sensor with time. However, the unavoidable noise in the sensor data may deteriorate the position estimation in case of the simple integration method. In general, a mobile robot has ready-to-use motion information from the encoder sensors of driving motors. By combining the velocity data from the optical mouse sensor and the motion information of a mobile robot, it is possible to improve the coordinate estimation performance. In this paper, a coordinate estimation algorithm for an autonomous mobile robot is presented based on the well-known Kalman filter that is useful to combine the different types of sensors. Computer simulation results show the performance of the proposed localization algorithm for several types of trajectories in comparison with the simple integration method.

• 제어로봇시스템학회논문지
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• 제2권4호
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• pp.337-343
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• 1996

In this paper, we investigate the defect detection by making use of pre-made reference image data and classify the defects by using the artificial neural network. The approach is composed of three main parts. The first step consists of a proper generation of two reference image data by using a low level morphological technique. The second step proceeds by performing three times logical bit operations between two ready-made reference images and just captured image to be tested. This results in defects image only. In the third step, by extracting four features from each detected defect, followed by assigning them into the input nodes of an already trained artificial neural network we can obtain a defect class corresponding to the features. All of the image data are formed in a bit level for the reduction of data size as well as time saving. Experimental results show that proposed algorithms are found to be effective for flexible defect detection, robust classification, and high speed process by adopting a simple logic operation.

• 한국멀티미디어학회논문지
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• 제6권1호
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• pp.105-113
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• 2003

CDMA 셀룰러 시스템 내에서 고속이동체에 대한 비효율적인 채널할당으로 호 블록킹 확률이 높아진다. 이를 위하여 고속이동체의 속도에 따른 전용 채널과 큐를 할당하여 계층셀에 적용해 속도에 따른 QoS를 보장하는 방식이 제안되었다. 본 논문에서는 현재 위치한 셀에서의 이동체의 수신 신호세기에 따라 HA에 트래픽이 적을 때에 FA 내에 고속 핸드오프 전용 채널을 할당하였다 또한 FA 내 신호세기가 약한 고속 핸드오프 호에 대하여 새로운 환형 큐 LiFA를 생성하여 고속 핸드오프 호를 LiFA에 호 지속시간 동안 대기시켜 호 강제종료율을 개선하였다.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2010년도 추계학술대회
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• pp.62-65
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• 2010

ITS는(지능형 교통 시스템: Intelligent Transport System)을 이용한 대중교통을 더욱 편리하게 이용하기 위하여 본 논문은 버스와 지하철의 도착 정보를 공용으로 서버처리 시스템을 연동하여 관리하고 네트워크로 실시간 정보를 사용자에게 전송하여 그로 인해 사용자가 편리하게 사용하며, 대중 교통 이용의 효율성을 위해서 관련된 기술이 최근 동향을 분석 간다.

• Clinical and Experimental Pediatrics
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• 제60권4호
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• pp.99-105
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• 2017

Food allergy (FA) is a serious health problem, and severe FA such as food-induced anaphylaxis can often be life threatening. The incidence of FA has been increasing especially in children. They usually develop early in life and affect up to 10% of children. The 2 most common food allergens worldwide are milk and eggs, while the third one varies depending on the countries: peanuts in the United States and Switzerland, wheat in Germany and Japan, tree nuts in Spain, sesame in Israel, and walnuts in Korea. These common food allergens are different and difficult to identify because of differing study methodologies, population, geography, age, and dietary exposure patterns. The current management of FA relies on the strict avoidance of culprit allergens, the prompt treatment of allergic reactions, including epinephrine use for food-induced anaphylaxis, monitoring, and education to prevent further reactions. Newer approaches for tolerance induction to FA and FA immunotherapy have been under investigation but are not yet ready for real-world application. Thus, consistent and systematic education of patients, caregivers, and food-handling people is of primary importance for the management and prevention of FA reactions. This review assesses and compares IgE-mediated FA in children in Korea and other countries, with a focus on summarizing the prevalence, common triggers, and management of FA.

• 한국자동차공학회논문집
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• 제2권4호
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• pp.91-99
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• 1994

Tunable KrF Excimer Laser is used here for measuring OH and $O_2$ density distribustion in an open $H_2$/air premixed flame and in a combustion bomb. Laser Rayleigh Scattering(LRS) and Planar Laser Induced Predissociative Fluorescence(PLIPF) methods are used to obtain two-dimensional images of total and specific densities. Laser Excitation wavelengths are calibrated via flame images and combustion bomb images show good qualitative a greement with theoretical calculation. Furthermore images in a combustion bomb can be developed to study real Spark-Ignition engine combustions. Our experimental images show that there are no more collisional quenching problem at high pressure environment(including atmospheric pressure) using predissociative fluorescence technique. Further development to obtain two-dimensional temperature dustribution is ready to use eventhough it is not reported in this paper.

• 한국건축시공학회지
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• 제13권1호
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• pp.38-47
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• 2013

When building with concrete in cold weather, an insulation method of heat curing must be determined, and a holistic curing plan that considers the characteristics of structures, the heat loss coefficient of a curing sheet, the joint condition of the curing materials and the quantity of heat produced by a heating apparatus is an essential prerequisite for protection against early frost damage. But on a number of national construction sites, there have been serious problems in cold weather concreting due to the unreliability of the information obtained from practical experience. In the construction field in Japan, there is a specification for heat curing prepared by Japanese Architectural Society, which provides an equation for calculating heat quantity. It is also necessary to adopt a detailed specification for a standard heat curing method that is applicable to all national construction sites. In this study, the effect of bubble sheets on the economic feasibility of cold weather concrete is investigated through a comparison with the blue sheets commonly prescribed in national construction sites. In conclusion, this study found that bubble sheets had the effect of reducing the cost of curing materials and the fuel cost consumed by a heating apparatus, compared to the use of blue sheets.

• 한국콘텐츠학회논문지
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• 제7권3호
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• pp.87-92
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• 2007

본 논문은 셋톱박스내의 개인형 비디오 레코더를 활용하여 디지털 텔레비전의 양방향성 구현하기 위한 해법을 다루고 있다. 지금까지는 디지털방송 중에 시청자가 요구하는 방대한 양의 다양한 인터랙티브 콘텐츠들을, 그것들이 데이터방송이건 HD급 방송이건간에, 소화해 내기란 힘든 일이었으며, 더군다나 IPTV가 출현하기 전까지는 상상도 못할 일이었다. 비록 초고속 인터넷을 통한 IPTV가 양방향 서비스를 가능하도록 하고는 있지만, 셋톱박스를 통해서 한 번에 방대한 양의 콘텐츠를 수신하기란 그리 쉬운 일은 아니다. 이 논문에서 본인은 디지털 방송에서 대용량의 인터랙티브 콘텐츠를 제공받는데 장애가 되는 다운로드 딜레마에 대한 효율적인 해법을 개인형 비디오 레코더가 장착된 셋톱박스를 통해 제시하고자 한다.

• 융합신호처리학회논문지
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• 제9권3호
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• pp.224-229
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• 2008

In the paper, a new Constraint algorithm is proposed to solve the fan-in problem occurred in the encoding circuitry of an ADC. The Flash ADC architecture uses a Double-Base Number System(DBNS). The DBNS has been known to represent the Multidimensional Logarithmic Number System (MDLNS) used for implementing the multiplier accumulator architecture of FIR filter in Digital Signal Processing (DSP) applications. The authors use the DBNS with the base 2 and 3 in designing ADC encoder circuits, which is called as Double Base Integer Encoder(DBIE). A symmetric map is analyzed first, and then asymmetric map is followed to provide addition ready DBNS for DSP circuitry. The simulation results of the DBIE circuits in 6-bit and 8-bit ADC show the effectiveness of the Constraint algorithm with $0.18{\mu}m$ CMOS technology. The DBIE yields faster processing speed compared to the speed of Fat Tree Encoder (FAT) circuits by 17% at more power consumption by 39%.