• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1993.10a
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• pp.413-422
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• 1993

Air shipment affords the quickest possible delivery of horticultural products. The price of air shipped horticultural products are relatively high as most of these products are perishable. Usually the temperature in the cargo compartment is not controlled during flight. Thus, special attention should be paid to procooling prior to shipment. The environmental condition during transportation of horticultural products is an essential parameter for maintaining the quality of perishable products. Commonly horticultural products were loaded by ULD(Unit Load Devices) as a container or pallet in the aircraft (except for small aircraft) . Therefore, inside temperature of the container and cargo compartment came into question. Scarce literature on the relationship between environmental condition and quality changes of horticultural products during air shipment can be found. By the stand point of keeping fresh quality, investigations on the actual condition of air shipments were carried out to improve the technique during the distribution process of fresh horticultural products. Temperature, humidity, atmospheric pressure, carbon dioxide, ethylene, impacts, and changes in quality during the air shipment of snapbeans, okras and chrysanthemums were measured. Temperature was measured by recording thermometers, relative humidity by recording hygrometers, atmospheric pressure by a strain -guage type pressure sensor, carbon dioxide by testing tubes, ethylene by sampling bags and a gaschromatograph, impacts and vibrations by impact recorders and a 3D accelerometer. Relationships between environmental conditions and quality changes during air shipments were clarified. It was expected from investigations into actual shipments that the ventilation and insulation properties of air freight containers were related to the quality of agricultural products. Aircraft can no directly load and unload trucks into them. The transshipment is inclined to cause shocks and vibrations, and to invite damages within a short time.

• The KSFM Journal of Fluid Machinery
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• v.13 no.2
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• pp.54-58
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• 2010

The most recent, Vacuum Pipeline for Waste Collecting System, to collect MSW(Municipal Solid Waste) efficiently, is used environmental preservative, to emit less air pollution, in New City. However, it is difficult to monitor broken pipe and filled mass of Waste, because Vacuum Pipeline is laid underground. Therefore, FBG, optical fiber sensor, is used to inspect the temperature change and longitudinal strain to take proper action for unusual situation. I have need to accumlate sensor data of district control. I hope to be used Vacuum Pipeline more than 30 years in New City.

• Journal of Institute of Control, Robotics and Systems
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• v.15 no.8
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• pp.867-875
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• 2009

A wireless sensor network inherently comprises a plurality of sensor nodes widely deployed for sensing environmental information. To add new functions or to correct some faulty functions of an existing wireless sensor network, the firmware for each sensor node needs to be updated. Firmware update would be quite troublesome if it requires the gathering, reprogramming, and redeploy of all of already deployed sensor nodes. Over-the-air programming (OTA) facilitates the firmware update process, thereby allowing convenient maintenance of an already-deployed sensor network. This paper proposes and implements a remote firmware update mechanism for a TDMA-based wireless sensor network, in which the firmware for sensor nodes constituting the TDMA-based sensor network can be easily updated and the update process can be conveniently monitored from a remote site. We verify the validity of the proposed firmware update method via experiments and introduce three wireless sensor networks installed in outdoor sites in which the proposed firmware update mechanism has been exploited.

• The Journal of the Korea institute of electronic communication sciences
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• v.16 no.1
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• pp.183-190
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• 2021

This study is a study on the implementation and operation of smart air cleaning system to improve indoor air quality. Recently, the problem of indoor air quality is getting serious due to various environmental factors. In this study, to improve the problems of indoor air quality, we implement an air cleaning system using IoT sensor. In particular, we proposed a system that can measure air pollution in real time and change different air flow paths according to pollution level. Through this, we examined efficient air quality improvement, extension of filter life, and system energy reduction. In addition, the main functions of the indoor air quality improvement system were constructed and prototypes were manufactured to confirm the operability. Finally, the utility of fine dust resolution through the implementation of the indoor air quality improvement system was examined.

• Corrosion Science and Technology
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• v.20 no.2
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• pp.94-104
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• 2021

Atmospheric corrosion severity associated with aircraft parking environment was studied using metallic specimens, and temperature and humidity sensors installed at each aircraft operating base. Data were analyzed after a year of exposure. Silver was used to measure chloride deposition by integrating X-ray photoelectron spectroscopy depth profiles. Carbon steel was utilized to determine the corrosion rate by measuring the weight loss. The time of wetness was determined using temperature and humidity sensor data. Analysis of variance followed by Tukey's "honestly significant difference" test indicated that atmospheric environment inside the shelter varied significantly from that of unsheltered parking environment. The corrosion rate of unsheltered area also varies with the roof. Hierarchical clustering analysis of the measured data was used to classify air bases into groups with similar atmospheric corrosion. Bases where aircraft park at a shelter can be grouped together regardless of geographical location. Unsheltered bases located inland can also be grouped together with sheltered bases as long as the aircraft are parked under the roof. Environmental severity index was estimated using collected data and validated using the measured corrosion rate.

• Journal of the Korean Association of Geographic Information Studies
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• v.14 no.4
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• pp.161-171
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• 2011

Most public organizations which charge for measuring or collecting environmental information provide web-based information services. In the case of Seoul, it is provided smart phone app for information services on region or district unit. However, there is no smart phone application for environment information services considering location-based services with the concept of personalization. The purpose of this study is to deign and implement a smart phone app for air environment and radioactive information services with these features. Hybrid type is adopted, so that several things are possible: access to a variety of devices by web languages, and N-Screen support is available. According as social needs with respect to more environmental information and their contents are increasing, this approach will be useful.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.4
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• pp.233-239
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• 2013

This study was carried out to develop the realtime evaluation system of $NH_3$ absorption efficiency with gas sensors which were installed on the inlet and outlet of lab-scale scrubber system. The $NH_3$ absorption amount, calculated by sensor outcomes for 3 hr, 6 hr, and 12 hr of absorption process, was compared with the results analysed by Indo-phenol method for the absorption solution. Even though the difference between two methods was about 20%, the correlation coefficient between the two results was very high, more than 0.99. In addition, we could find very good correlation between pH, absorption amount and reaction time. Also we could find out the breakthrough time in the middle of absorption process. With more diverse experiment in the future, we can make gas sensor system for the realtime evaluation of the odor and/or air pollution treatment efficiency.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.49 no.2
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• pp.147-154
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• 2021

In this paper, the configuration and design of the test equipment are presented to examine the impact of rapid temperature change in cooling-air that may occur during the operation of the fixed wing aircraft Environmental Control System (ECS) on avionic electronic equipment. At the start of the ECS, the temperature of the air supplied by the aircraft ECS may be increased to 5.0℃ per second. In order to ensure operating of the avionic electronic equipment that is mounted on the aircraft and receives cooling-air from the ECS, testing equipment that can implement the cooling-air characteristic test environment is required. During design of test equipment was verified cooling-air rapid rate of temperature change by performing a thermal/flow analysis, performance of the test equipment implemented was verified by applying an avionic electronic equipment.

• Journal of Environmental Science International
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• v.17 no.5
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• pp.501-507
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• 2008

The concentrations of HCHO(formaldehyde), $PM_{10}$(particulate matter), $CO_2$(carbon dioxide) and TBC(total bacteria counter) distribution in schools(Chung-Nam Area) were examined, and the results were compared with the recommended criterion of the administration law of indoor air. The subjects were an elementary school, a middle school and a high school in Chung-Nam area, and the concentration of TBC was examined by Single Stage Air Cascade Sampler, which applied the inertia collision catching method of 28.29L/min(flux) during 5 months from March, 2007 to July, 2007. The instrument(LD-3B, SIBATA Company)was used to examine $PM_{10}$, by a light scattering method and a light transmission method. The instrument(Airboxx(KD Engineering) was used to examine $CO_2$. The instrument(Z300XP(Environmental sensor)was used to examine HCHO. The result indicated that the $PM_{10}$ average concentrations of the surveyed classrooms were $49{\mu}g/m^3$ in Spring and $59{\mu}g/m^3$ in Summer. The $CO_2$ average concentration of the surveyed schools were 576 ppm in the classroom and 527 ppm in the stateroom. The average concentration of TBC were $729CFU/m^3$ in an elementary school, $401CFU/m^3$ in a middle school, $381CFU/m^3$ in a high school. The HCHO average concentration of the surveyed schools were 0.03 ppm in the classroom, 0.02 ppm in the stateroom.

• Proceedings of the KSRS Conference
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• 2005.10a
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• pp.392-393
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• 2005

Due to the temporal and spatial simultaneity and the high-frequency repetition, the data set retrieved from the satellite observation is considered to be the most desirable ones for the study of air-sea interaction. With rapidly developing sensor technology, satellite-retrieved data has experienced improvement in the accuracy and the number of parameters. Nevertheless, since it is still impossible to directly measure the heat fluxes between air and sea, the bulk method is an exclusive way for the evaluation of the heat fluxes at the sea surface. It was noted that the large deviation of air temperature in the winter season by the linear regression despite good correlation coefficients. We propose a new algorithm based on the Fourier series with which the SST and the air temperature. We found that the mean of air temperature is a function of the mean of SST with the monthly gradient of SST inferred from the latitudinal variation of SST and the spectral energy of air temperature is related linearly to that of SST. An algorithm to obtain the air temperature over the sea was completed with a proper analysis on the relation between of air temperature and of SST. This algorithm was examined by buoy data and therefore the air temperature over the sea can be retrieved based on just satellite data.