• Journal of Appropriate Technology
• /
• v.6 no.2
• /
• pp.136-145
• /
• 2020

Agriculture is the backbone of the economy of most developing countries. In these countries, agriculture or farming is mostly done manually with little integration of machinery, intelligent systems and data monitoring. Irrigation is an essential process that directly influences crop production. The fluctuating amount of rainfall per year has led to the adoption of irrigation systems in most farms. The absence of smart sensors, monitoring methods and control, has led to low harvests and draining water sources. In this research paper, we introduce a 433 MHz Radio Frequency and 2G based Smart Irrigation Meter System and a water prepayment system for rural areas of Tanzania with no reliable internet coverage. Specifically, Ngurudoto area in Arusha region where it will be used as a case study for data collection. The proposed system is hybrid, comprising of both weather data (evapotranspiration) and soil moisture data. The architecture of the system has on-site weather measurement controllers, soil moisture sensors buried on the ground, water flow sensors, a solenoid valve, and a prepayment system. To achieve high precision in linear and nonlinear regression and to improve classification and prediction, this work cascades a Dynamic Regression Algorithm and Naïve Bayes algorithm.

• Journal of the Korea institute for structural maintenance and inspection
• /
• v.27 no.4
• /
• pp.1-10
• /
• 2023

In the seismic design of structures, seismic forces are calculated based on structural models and analysis. In order to accurately address the dynamic characteristics of the actual structure in the structural model, calibration based on actual measurements is required. In this study, a 4-story frame test specimen was manufactured to simulate frame building, accelerometers were attached at each floor, and 1-axis shaking table test was performed. The natural period of the specimen was similar to that of the actual 4 story frame building, and the columns were designed to behave with double-curvature having the infinite stiffness of the horizontal members. To investigate the effects seismic waves characteristics, historical and artificial excitations with various frequencies and acceleration magnitudes were applied. The natural frequencies, damping ratios, and mode shapes were obtained using frequency response functions obtained from dynamic response signals, and the mode vector deviations according to the input seismic waves were verified using the Mode assurance criterion (MAC). In addition, the damping ratios obtained from the vibration tests were applied to the structural model, and the method with refined dynamic characteristics was validated by comparing the analysis results with the experimental data.

• Proceedings of the Korean Institute Of Construction Engineering and Management
• /
• 2008.11a
• /
• pp.753-757
• /
• 2008

The objects of this study are to increase the efficiency and competitiveness for construction management and field supervision by using IT technology which is a trend of construction industry thesedays. Using RFID technology can play an important role to achieve the goal, but it is necessary to research a standard of using frequency, specific, protocol, package method and reading method because it is hard to apply RFID to physical, chemical, environmental specifics. In this study as a part of planning research to standardize, a limitation item Is conducted with RFID tag attached building materials, and RFID Tag goods which solve the restriction are produced to conduct a field application test. From the result, available reading distance is different according to physical and environmental specifics. Furthermore because the different application method and attaching method make a various management efficiency, the current management of construction materials is analyzed and applied to a construction field to provide to various limitation items and recovery plan.

• The Journal of Society for e-Business Studies
• /
• v.12 no.3
• /
• pp.75-93
• /
• 2007

This paper presents real-time online early fire warning systems developed for preserving cultural properties of Bulguksa which is a world heritage designated by UNESCO. The system is based on the ubiquitous sensor network employing 900MHz and 2.4GHz bands. In this paper, we analyze requirements that should be considered in building effective management systems of cultural heritages by using wireless sensor network. Finally, we introduce the architecture, sensor and network design, and software design of the fire warning systems which is an initial version of U-Bulguksa. The current version of systems has been operating in Bukguksa for a few months. U-Bukguksa project sponsored by National Information Society Agency is ultimately aimed at developing an integrated system of U-cultural heritage management and U-tourism. The former aims to conserve and manage intangible cultural properties by providing a variety of environmental information such as erosion, crack, and gradient as well as fire which are important causes of loss and damage in real-time and online. The latter refers to the intelligent tourism information and guidance systems allowing tourists to get the personalized content on cultural heritages and help guidance with mobile devices in Bulguksa.

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
• /
• v.8 no.4
• /
• pp.1-69
• /
• 1997

국립기술품질원은 최근 전기용품안전관리법에 의한 전기용품기술기준의 내용 중 전자파장해와 관련된 시험기준 및 측정방법을 대폭 개정하였다. 이 개정은 국립기술품질원 고시 제 1997-140호(1997. 7. 9.)에 의해 이루어졌는데 개정내용의 주요골자는 기존 전자파장해 분야의 기준 및 측정방법을 전면적으로 수정, 보완하고 전자파내성분야의 기준 및 측정방법을 신규로 추가 삽입한 것으로 판단된다. 주지하다시피 전자파장해와 관련해서 우리나라의 국가규격은 전파법에 의한 기술규격과 전기용품 안전관리법에 의한 기술규격으로 양분화되어 있다. 전파법에 의한 기술규격은 작년에 정보통신부 고시 제1996-78, -79, -80, -81호(1996. 10. 9.)에 의해 종전의 전자파장해검정규칙에 따른 시험방법을 CISPR에 의한 모든 대상기기에 대해 전자파장해 및 전자파내성 관련 기술기준 및 시험방법을 대폭 개정한바 있으며, 본 전기용품안전관리법에 의한 기술기준 개정은 전자파장해 및 내성에 관련 내용을 최근의 국제기술동향에 부응하도록 망라하여 정리한 것이라는 관점에서는 전파법에 의한 개정내용과 유사한 것으로 여겨지나, 다만 그 대상기기가 전기 용품으로 한정된 것이 다른 것으로 사료된다. 종전의 전기용품안전관리법에 의한 전자파장해 기술규격은 국제규격인 CISPR의 권고사항을 따르되, 국내 산업계의 의견을 반영하여 측정주파수 범위, 기술기준, 측정방법 등의 내용에 있어서 다소의 수정을 가하였으며, 정보기술기기에 대해서는 미국의 FCC기술기준을 위주로 하여 제정된 것이었다. 금번 기술기준 개정은 전자파장해 분야에 있어서 이와 같은 종전의 기술기준을 최초의 CISPR 기술동향을 최대한 여과없이 반영시키도록 수정하였으며, 전자파내성 분야에 대해서는 전체적으로 IEC 1000-4-Series의 내용을 기본으로 하였으나, 여기에 추가적으로 디지털 무선전화기에 대한 방사내성 시험항목을 ENV55024의 내용을 위주로 하여 신규로 작성한 것으로 볼 수 있다. 따라서 기술기준의 개정사항은 주로 전자파장해 분야로 국한되어 있으며, 전자파내성 분야는 신규 제정한 것으로서 본고에서는 종전의 기술기준에서 전자파장해분야의 변경사항과 신규로 제정된 전자파내성 측정방법과 시험기준을 소개하는 거승로 하겠다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2006.05a
• /
• pp.931-934
• /
• 2006

Recently, as the problems related to agricultural product's safety occur continuously, the system with traceability that can quickly trace back the agricultural products with problems occurred and enable the analysis of causes and prohibition of distribution is required. Therefore, the recording of distribution data is important for this system and for this purpose, the RFID technology that can perceive tags from remote place through radio frequency can be effectively used. But, since the RFID is a technology that is being watched recently, the system that processes RFID tags and distribution data is trifling. Hereby, this thesis designed and implemented the RFID processing system that enables the career trace by analyzing and managing the data on recorded RFID tags and career data based on the standard of traceability.

• The Journal of the Acoustical Society of Korea
• /
• v.40 no.1
• /
• pp.92-98
• /
• 2021

The noise management in the interior of the power plant is difficult because the interior is large and the noise level varies greatly from location to location. Therefore, a noise visualization system capable of analyzing the noise distribution is required in order to effectively manage the interior noise. A noise mapping system was developed that can model the inside of the turbine room and create a noise map by measuring the noise level at selected points. And in order to increase the reliability of the model, the model was modified through a method of comparing the noise map and the actual noise measurement results. Facility abnormalities can be determined through regular analysis of noise maps, and a method of effectively managing the interior noise is presented by comparing and analyzing the frequencies and levels of the current and previous noise at a specific point. By using the mapping system, it is possible to establish noise countermeasures that can improve the working environment, check the machine for abnormalities, and increase the reliability of the facility through preventive maintenance.

• Korean journal of applied entomology
• /
• v.50 no.1
• /
• pp.39-46
• /
• 2011

This study analyzed effects of different sound treatments in frequencies and intensities on digestion and immune physiological processes of the beet armyworm, Spodoptera exigua larvae. Without effect on egg hatch, sound treatments with 100-5,000 Hz at 95 dB suppressed feeding behavior and inhibited a digestive enzyme activity. In addition, two dimensional electrophoresis of midgut luminal proteins indicated a marked difference of the sound-treated larvae. In response to 5,000 Hz at 95 dB, larvae showed a significant decrease in hemocyte nodule formation against fungal challenge along with significant suppression in phospholipase $A_2$ activity in hemocyte and plasma. With increase of sound frequencies, the treated larvae showed an enhanced susceptibility to insecticides. Such sound frequency effect was significantly modulated with different sound intensities. These results suggest that sound treatment may give adverse stress to physiological processes of S. exigua larvae and may be applied to a nonchemical insect pest control.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.21 no.2
• /
• pp.109-121
• /
• 2003

Lots of various utilities are buried under the surface. The effective management of underground utilities is becoming the very important subject for the harmonious administration of the city. Ground Penetrating Radar(GPR) survey including other various underground survey methods, is mainly used to detect the position and depth of buried underground utilities. However, GPR is not applicable, under the circumstances of shallow depth and places, where subsurface materials are inhomogeneous and are composed of clay, salt and gravels. The aim of this study is to overcome these limitations of GPR and other underground surveys. High-frequency electromagnetic (HFEM) method is developed for the non-destructive precise deep surveying of underground utilities. The method is applied in the site where current underground surveys are useless to detect the underground big pipes, because of poor geotechlical environment. As a result, HFEM survey was very successful in detecting the buried shallow and deep underground pipes and in obtaining the geotechnical information, although other underground surveys including GPR were not applicable. Therefore this method is a promising new technique in the lots of fields, such as underground surveying and archaeology.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2015.10a
• /
• pp.669-672
• /
• 2015

Recent Internet of Things (IoT, Internet of Things) that can be applied to various fields as the development of technology has been developed a lot of service and has been developed with the service also for crop management. To manage the essential elements of soil moisture in the crop growth but existing a direct person measuring the fluid point to carry the measuring instrument, if you take advantage of the WPAN (Wireless Personal Area Network) in this paper to manage sensor data, a fixed 3 points (30, 60, 90 cm) and can be managed can be scientifically analyzed the state of growth of the crop. Open field environment is utilized as it is less disturbance of the interference and the frequency of the radio frequency signal of the structure provides a relatively comfortable environment. Therefore, WPAN building and data transmission scheme of the minimum cost is to be developed. In addition, the operation to enter low power mode, the algorithm is necessary because a lot of restrictions on the power supply applied to the sensor nodes and the gateway is constructed in the open field. In the experiment, verifying the effectiveness by using a network configuration of each of the sensor nodes and the gateway, and provides a method for time synchronization of the operation and a low power mode. The study protocol for the RF communication with the LoRa and to enhance communication efficiency is needed in the future.