• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 춘계 학술발표회
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• pp.457-467
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• 2010

The settlement prediction is very important to preloading method for a construction site on a soft ground. At the design stage, however, it is hard to predict the settlement exactly due to limitations of the site survey. Most of the settlement prediction is performed by a regression settlement curve based on the field data during a construction. In Korea, hyperbolic method has been most commonly used to align the settlement curve with the field data, because of its simplicity and many application cases. The results from hyperbolic method, however, may be differed by data selections or data fitting methods. In this study, the analyses using hyperbolic method were performed about the field data of $\bigcirc\bigcirc$ site in Pusan. Two data fitting methods, using an axis transformation or an alternative method, were applied with the various data group. If data was used only after the ground water level being stabilized, fitting results using both methods were in good agreement with the measured data. Without the information about the ground water level, the alternative method gives better results with the field data than the method using an axis transformation.

• 한국환경과학회지
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• 제25권10호
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• pp.1389-1396
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• 2016

A monitoring system for a field magnetometer was configured with assistance of a Raspberry Pi as a data logger. The suggested geomagnetic system uses a semi-real-time data transmission module. The system consists of two parts: a field-observation part and a data-center part. The field-observation part comprises a Raspberry Pi, magnetometer, LTE router, and power source, while the data center part takes samples at the site. The collected magnetometer data are then sent to the data center through the LTE router. The newly designed monitoring system was deployed and checked in Jeju-do island, and found to operate stably. The suggested system is promising in that it is simple and cost saving, providing at least physical insight and knowledge on the complex natural phenomena.

• Wind and Structures
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• 제28권4호
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• pp.239-253
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• 2019

Accurate numericalsimulation of wind field over complex terrain is an important prerequisite for wind resource assessment. In this study, numerical simulation of wind field over complex terrain was further carried out by taking the complex terrain around Siu Ho Wan station in Hong Kong as an example. By artificially expanding the original digital model data, Gambit and ICEM CFD software were used to create high-precision complex terrain model with high-quality meshing. The equilibrium atmospheric boundary layer simulation based on RANS turbulence model was carried out in a flat terrain domain, and the approximate inflow boundary conditions for the wind field simulation over complex terrain were established. Based on this, numerical simulations of wind field over complex terrain under different inflow wind directions were carried out. The numerical results were compared with the wind tunnel test and field measurement data for land and sea fetches. The results show that the numerical results are in good agreement with the wind tunnel data and the field measurement data which can verify the accuracy and reliability of the numerical simulation. The near ground wind field over complex terrain is complex and affected obviously by the terrain, and the wind field characteristics should be fully understood by numerical simulation when carrying out engineering application on it.

• 한국신뢰성학회지:신뢰성응용연구
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• 제18권3호
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• pp.250-259
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• 2018

Purpose: Previously, missile reliability prediction is based on theoretical failure prediction model. It has shown that the predicted reliability is inadequate to real field data. Although an MTTF based reliability prediction method using real field data has recently been studied to overcome this issue. In this paper, we present a more realistic method, considering MTBF concept, to predict missile reliability. Methods: In this paper we proposed a modified survival model. This model is considering MTBF as its core concept, and failed missiles in the model are to be repaired and redeployed. We compared the modified model (MTBF) and the previous model (MTTF) in terms of fitness against the real failure data. Results: The reliability prediction result of MTBF based model is closer to fields failure data set than that of MTTF based model. Conclusion: The proposed MTBF concept is more fitted to real failure data of missile than MTTF concept. The methodology of this study can be applied to analyze field failure data of other similar missiles.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 2000년도 THE THIRD INTERNATIONAL CONFERENCE ON AGRICULTURAL MACHINERY ENGINEERING. V.III
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• pp.819-826
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• 2000

This study was performed to develop a measurement system of tractor field performance for plow and rotary operations. Measurement system for tractor consisted of torque sensors to measure torque of drive axles and PTO axle, speed sensors to measure rotational speed of drive axles and engine, microcomputer to control data logger, and data logger as I/O interface system. The measurement system was installed on four-wheel-drive tractor. Four-element full-bridge type strain gages were used for torque measurement of drive axles and optical encoders were used to measure speeds of drive axles and engine. Slip rings were mounted on the rotational axles. Signals from sensors were inputted to data logger that was controlled by microcomputer with parallel communication. Sensors were calibrated before the field tests. Regression equations were found on completion of the calibrations. The field experiment was performed at paddy fields and uplands. Rotary and plow were used when the tractor was operated in the field. Travelling speeds of the tractor were 1.9 km/h, 2.7 km/h, 3.7 km/h, 5.5 km/h, 8.2 km/h, and 11.8 km/h. Operating depths of implements were maintained approximately 20cm during the tests. Torque data of drive axles were different at each location during plow and rotary operations. Results showed that torque of rear axles were greater than those of front axles. Total torque were 6860 - 11064 Nm at the upland and 7360 - 14190 Nm at the paddy field for plow operations. It was found that torque at the paddy field were about 20% greater than those at the upland for plow operations. Torque data showed that rotary operations required less power than plow operation at the paddy field and the upland. Torque measurements at each axle for rotary operations were only 8 - 16% of plow operations in the upland and 15 - 20% in the paddy field.

• 한국방재학회:학술대회논문집
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• 한국방재학회 2007년도 정기총회 및 학술발표대회
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• pp.391-394
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• 2007

The field survey of a tsunami damage is carried out to collect and obtain real data. There data can be used to make the countermeasures against possible tsunami attackings. In the survey, many data collecting techniques such as interviewing with local people, taking pictures of the inundated field, recording the location by the GPS, measuring the level and distance of the maximum flood level can be used for practical and effective survey.

• 한국도서관정보학회지
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• 제51권4호
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• pp.83-100
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• 2020

오픈 사이언스 시대 연구데이터의 공개를 가속화하고 접근성 및 인용가능성 개선 및 연구데이터에 대한 표준화된 기술문서 제공은 또 다른 과학적 발견에 기여할 수 있어 데이터 출판이 주목을 받고 있다. 또한 출판된 데이터 역시 연구논문과 동등한 지위를 유지할 수 있는 방안으로 데이터 논문이 대두되고, 새로운 학술출판의 유형으로 데이터 저널 발간이 증가추세에 있다. 특히 생태학 분야는 대규모 연구데이터가 생산되고 관리되어야 하는 분야로 전세계적으로 데이터 저널 발간이 활발하다. 반면 국내에는 데이터 저널 연구가 초기 단계이고, 생태학 분야 데이터 저널이 전무하다. 이에 본 연구에서는 생태 분야의 데이터 저널을 발간하기 위한 전략을 탐색하고 제시하였다. 먼저 국내외 데이터 저널 발간 현황과 국내 저널 출판 현황을 조사하였다. 또한 학술출판 및 오픈액세스 정책 전문가, 생태학 학술지 발간 전문가로 구성된 전문가그룹 인터뷰를 수행하였다. 현재 데이터 저널 발간 인프라가 제대로 구축되지 않고 이에 대한 평가체제가 갖추어 지지 않은 국내 학술출판 관행을 반영하고 국내외 조사결과와 전문가 FGI를 실시 결과를 바탕으로 생태학 분야 데이터 저널 출간 방향, 데이터 논문 투고지침, 저널 구성 및 발행주기, 저널 편집위원 구성, 원고의 수급 측면에서 전략을 제시하였다.

• 한국농공학회논문집
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• 제50권3호
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• pp.83-89
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• 2008

Estimations of paddy field area are important for agricultural water supply planning. Especially these estimations have to be excused by drainage basin. In this research, we developed a paddy field estimation model considering shift-share effects such as national growing, structural, local effects. National growing effects are estimated by adopting the result of KREI-ASMO model which predict farm land area in national level. Paddy field structural effects are estimated using statistical data about farmhouse numbers and cultivation areas. Local allocation effects are calculated by differences of estimations and real data. The results using data from 1998 to 2003 show that developed model estimates 2006 paddy field areas in each province in 5% error and is applicable to predict future change of paddy field.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2000년도 춘계학술대회논문집
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• pp.1752-1761
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• 2000

This paper describes the far-field estimation using the near-field measurement data. Measurement in far-field region gives us the acoustical characteristics of the source but in general measurement is made in near-field such as acoustic water tank or anechoic chamber, so far-field acoustical characteristics of the source should be predicted from near-field data. In this case, the number of measurement points in the near field which relates to the accuracy of the predicted field and the amount of data processing, should be optimized. Existing papers say that measurement points is proportional to kL and depends on geometry and directivity of the source. But they do not give us any definite criterion for the required number of measurement points. Boundary Collocation Method which is one of the far-field prediction methods, is analyzed based on Helmholtz integral equation and Green function and it has been found that the number of measurement points is optimized as 0.54kL which is about one half of the existing results.

• 정보관리학회지
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• 제37권3호
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• pp.77-106
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• 2020

본 연구에서는 학제 간 연구가 가장 활발하고 응용가능성이 가장 높은 응집물질물리분야의 연구데이터를 체계적으로 관리하기 위한 개선방안을 제안하였다. 이를 위해 연구데이터 관리 도구인 Data Asset Framework (DAF)와 데이터 공유 및 재사용을 위한 FAIR원칙을 바탕으로 설문 내용을 구성하여 14명의 연구자를 대상으로 응집물질물리분야의 연구데이터 관리 현황을 수집하였다. 수집된 데이터는 설문에 응답한 연구자의 특성 및 기초정보, 데이터 보존 및 관리, 데이터 공유 및 접근에 관한 데이터로 구성되었다. 수집된 설문결과를 분석하여 응집물질물리분야의 연구데이터 특징과 데이터 수집과 생산, 데이터 보존과 관리, 데이터 공유 및 접근에 대한 9가지 문제점을 도출하였으며, 각 측면에서 도출된 문제점에 대한 개선방안을 제언하였다.