• Journal of Wetlands Research
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• 제22권4호
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• pp.312-320
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• 2020

Various LIDs with natural water circulation function are applied to reduce urban environmental problems and environmental impact of development projects. However, excessive Infiltration and evaporation of LID facilities dry the LID internal soil, thus reducing plant and microbial activity and reducing environmental re duction ability. The purpose of this study was to develop a real-time measurement system with complex sensors to derive the management plan of LID facilities. The test of measurable sensors and Internet of Things (IoT) application was conducted in artificial wetlands shaped in acrylic boxes. The applied sensors were intended to be built at a low cost considering the distributed LID and were based on Arduino and Raspberry Pi, which are relatively inexpensive and commercialized. In addition, the goal was to develop complex sensor measurements to analyze the current state o f LID facilities and the effects of maintenance and abnormal weather conditions. Sensors are required to measure wind direction, wind speed, rainfall, carbon dioxide, Micro-dust, temperature and humidity, acidity, and location information in real time. Data collection devices, storage server programs, and operation programs for PC and mobile devices were developed to collect, transmit and check the results of measured data from applied sensors. The measurements obtained through each sensor are passed through the Wifi module to the management server and stored on the database server in real time. Analysis of the four-month measurement result values conducted in this study confirmed the stability and applicability of ICT technology application to LID facilities. Real-time measured values are found to be able to utilize big data to evaluate the functions of LID facilities and derive maintenance measures.

• Journal of the Korea Organic Resources Recycling Association
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• 제11권1호
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• pp.149-153
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• 2003

This study was conducted to survey the utilization possibility of composting system of small scale static pile with animal manure produced from cattle shed and the effect of addition of microorganism on the maturity of compost. Microorganisms added in composting substrate were bacteria+lactobacillus(BL)+photo.(BLP). The composting practiced was a windrow system without aeration equipment and turning was practiced periodically. The water content of substrate mixed with cow manure, rice husk, and sawdust was about 60%. The temperature during the composting process was increased at over $60^{\circ}C$ within 3 days after composting starting. Increase of temperature at the early stage of composting was fasten in BLP and BL than Control. Because the pH of the raw material was high, the changes of pH during composting was little and stabilized in weak alkaline condition. EC value was high for accumulation of manure and urine excreted continuously by animal and the changes of those during composting occurred in 5~10% increase. Reduction rates of C/N ratio were the largest as the 22.7% in BLP and 19.2and 17.5% in BL and Control respectively. In the evaluation of phytotoxicity, there was stabilized within the short time in BLP and not the difference between BL and Control. Treatment of animal manure produced from small scale cattle shed was possible by using the small scale static pile composting system with reasonable water content and turning and the addition of microorganism in composting substrate was effected on the temperature increase at the early stage of composting and reduction of plant toxicity compounds but little on the maturity of compost.

• The Korean Journal of Pesticide Science
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• 제12권2호
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• pp.162-167
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• 2008

To enhance the control efficacy against cockroaches in dwelling space, repellent ("Push") was set down on one comer and a poison bait including attractant ("Pull") was on the opposite side. And we tested the control efficacy of Push-Pull strategy by behavior-stimuli of cockroaches. In a mini-field test, German cockroach males primarily chose shelters nearest to the attractant-treated surfaces and farthest from the repellent-treated surfaces. The consumption of food or bait was also highest from food nearest to the preferred shelters by push-pull effect. We evaluated the push-pull insecticidal efficacies of five essential oils belong to Citrus plant, namely, grapefruit, lemon, lime, orange, and petitgrain. The combined push-pull treatments appeared to be faster and higher insecticidal effects than single (pull) treatment, and the repellent efficacy of Citrus oils was in the order of grapefruit > lemon > lime > orange > petitgrain. Therefore, we propose the effective control of the german cockroach using Citrus oils as repellents and push-pull method into a limited area.

• The Journal of Korean Society for Radiation Therapy
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• 제26권1호
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• pp.37-42
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• 2014

Purpose : At the time of the pelvis cancer radiation treatment using the belly board, set-up error is large because of a prone position. In order to improve the reproducibility, we made Vac-lock type belly board. In this study, we attempt to validate its utility. Materials and Methods : We compared belly board and Vac-lock type belly board through the OBI. OBI was performed three times with entire course of treatment and the setup errors in the direction of X axis, Y axis, Z axis were recorded and calculated the distance from the isocenter. Results : X axis, Y axis, Z axis setup errors with existing belly board were 0.32 cm, 0.41 cm, 0.29 cm. The setup errors with the vac-lock type belly board were 0.12 cm, 0.19 cm, 0.17 cm. Further, errors of 0~0.29 cm were increased from 48% to 83% when using VLT belly board. Error of 0.5 cm or more was reduced from 21% to 2%. Conclusion : Vac-lock type belly board is able to maintain the efficacy of existing and create to match the characteristics of the patient. Therefore We think that vac-lock type belly board is very useful in pelvic cancer patients.

• Journal of Korean Society of Environmental Engineers
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• 제31권10호
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• pp.901-908
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• 2009

We examine the processing method of the food wastewater to direct spray at living waste incinerator. The demoscale stoker system is used as a incineration facility. The results show that it brings effect on the reduction of nitrogen oxide ($NO_x$) concentration as well as the ammonia ($NH_3$) amount in SNCR (selective non-catalytic reduction) by the incineration of food wastewater which is containing a plentiful ammoniac nitrogen ($NH_3$-N). Furthermore, the stability of incineration facility and the extension of operation period is actualized as a improvement of clogging phenomenon on outer wall of water pipe as the 870~$950^{\circ}C$ maintain of exit temperature in a second combustor by spray of the food wastewater. The 26 items of air pollution matter of nitrogen oxide ($NO_x$), sulfur oxide ($SO_x$) and dioxin etc. are measured. The results show that it is under the value of allowable exhaust standard.

• Journal of Korean Society of Environmental Engineers
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• 제31권2호
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• pp.90-95
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• 2009

Sludge pre-treatment utilizing cavitation is one of the commercialized methods at present. Cavitation can be generated by two different methods, sonotrode and hydrodynamic principle, and there has been no direct comparison between the two methods. In this study, solubilization efficiency, changes in sludge size distribution, and the methane production potential after pre-treatment by the two methods were compared. The maximum solubilization efficiency per unit energy input with the two methods was similar, and was 302 mg ${\Delta}SCOD/g$ TS at the energy input of 0.18 kWh/L. Break-up of sludge flocs were dominant during the early period of pre-treatment, while cell disintegration continued through the pre-treatment with the increase in the number of particles with less than 1 ${\mu}m$. BMP test results indicated that the methane potential increased up to 24.3% without differences between the two pre-treatments, and the increase in methane potential did not proportional to energy input. Although the energy efficiency of the two methods was quite similar, hydrodynamic methods might be a better choice for field application considering the operation and maintenance cost, and its potential improvement in energy efficiency.

• Journal of Korean Society of Environmental Engineers
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• 제37권5호
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• pp.262-268
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• 2015

This study established an analytical method to simultaneously determine six organophosphorous pesticides [methyldemetone-S, diazinon, fenitrothion, parathion, phentoate, and O-ethyl O-(4-nitrophenyl) phenylphosphonothioate (EPN)] and carbaryl in water using a gas chromatography/mass spectrometry (GC/MS) system coupled with on-line micro extraction by packed sorbent (MEPS) and programmed temperature vaporizer (PTV) injector. Polystyrene divinylbenzene (PDVB) was used as a sorbent of MEPS. The effects of elution solvents, pH, elution volume and draw-eject cycles of samples on sample pretreatment process were investigated. Also, quality assurance and quality control (QA/QC) and the recovery of the pesticides in environmental samples were evaluated. The elution was performed using $30{\mu}L$ of a mixed solvent (acetone : dichloromethane = 80 : 20 (v/v)). Sample pretreatment processes were optimized with seven cycles of draw-eject of sample (1 mL) spiking an internal standard and sulfuric acid. At lower pH, the analytical sensitivity of diazinon decreased, but that of carbaryl increased. The method detection limit and the limit of quantification for this method were 0.02~0.18 and $0.08{\sim}0.59{\mu}g/L$, respectively. The method precision and accuracy were 1.5~11.5% and 83.3~129.8%, respectively, at concentrations of $0.5{\sim}5.0{\mu}g/L$. The recovery rates for all the pesticides except carbaryl in various environmental samples ranged 75.7~129.3%. The recovery rate of carbaryl in effluent sample was over 200% whereas carbaryl in drinking water, groundwater, and river water were in the acceptable range.

• Journal of the Korean Society for Marine Environment & Energy
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• 제8권2호
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• pp.78-82
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• 2005

Fishermen have higher risk of occupational injuries and disease due to frequent machine usage and direct contact to live biological materials. Moreover, growing elderly workers makes the susceptibility to occupational injuries and disease higher. This study was performed to investigate the occupational safety and health status among fishermen. The interview was carried out at Jumunjin and Geojin ports which were representative port at North East side of Korea. The structured questionnaire were used to interview the fishermen from AM 6:00 to PM 11:00 and total respondent were 97 workers. The results were followed; 7 fishermen of all respondents experienced occupational injuries during their work, 5 fishermen were needed to admission longer than 4 days. The injury types were contusion(4 persons), fracture(1 persons) and amputation(2 persons). The cause of injury might be the lack of caution and the unstability of working condition. These results suggested the ergonomical evaluation of working condition and proper management. But there was limited concern and studies on the policy on occupational safety and health on fishermen. So, further study was required to establish the sound policy of fishermen's occupational safety and health.

• Journal of the Korean Applied Science and Technology
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• 제33권1호
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• pp.67-74
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• 2016

The Prussian Blue Analogue(PBA) has three dimensional structure and the metal - organic framework material, and it has a variety configurations depending on the type of organic ligands. PBA has been receving an attention in the fields of biosensors, optical, catalytic, and hydrogen storage device. Also, it is an environmental friendly substance with a chemical stability. In addition, PBA is widely used in the filed of adsorption art since we can adjust the size of the fine pores. In this study, we synthesized $Mn_3[Fe(CN)_6]_2$, an organometallic framework chains by using a hydrothermal synthesis method. We used $K_4[Fe(CN)_6]$ and $MnCl_2$ as precursors. We also produced a manganese iron oxide, by baking the synthesized material. The effect of the size and shape of the particles was examined by controling pH of the precursor solution, the molar concentration of the precursor, and reaction time as the experimental variables. Synthesized absorbent was analyzed by XRD, SEM, FT-IR, UV-Vis, and TG / DTA to evaluate the adsorption properties of several dyes.

• Journal of the Earthquake Engineering Society of Korea
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• 제14권6호
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• pp.1-9
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• 2010

Most of shear wall structures require openings in shear walls and thus shear walls are linked by floor slabs or coupling beams resulting in the coupled shear wall structures. When these structures are subjected to seismic excitations, excessive shear forces are induced in coupling beams. Accordingly, brittle failure of coupling beams may occur or shear walls may yield first. To avoid this problem, damping devices can be installed in coupling beams. It can increase the vibration control effect and improve the seismic resistance performance of the coupled shear wall structure by avoiding stress concentration and the brittle failure of coupling beams. Based on this background research, an LRB (lead rubber bearing) was introduced in the middle of the coupling beam in this study and the authors investigated the seismic response control effect and stress distribution of the proposed system. To this end, a modeling technique that can effectively predict the structural behavior of coupled shear wall structures has been proposed. With this proposed technique, time history analyses of the example coupled shear wall structure subjected to seismic excitation were performed and the vibration control effects of the seismic responses were investigated.