• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.34 no.6
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• pp.619-627
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• 2016

Cells of a PV (photovoltaic) module can suffer defects due to various causes resulting in a loss of power output. As a malfunctioning cell has a higher temperature than adjacent normal cells, it can be easily detected with a thermal infrared sensor. A conventional method of PV cell inspection is to use a hand-held infrared sensor for visual inspection. The main disadvantages of this method, when applied to a large-scale PV power plant, are that it is time-consuming and costly. This paper presents an algorithm for automatically detecting defective PV panels using images captured with a thermal imaging camera from an UAV (unmanned aerial vehicle). The proposed algorithm uses statistical analysis of thermal intensity (surface temperature) characteristics of each PV module to verify the mean intensity and standard deviation of each panel as parameters for fault diagnosis. One of the characteristics of thermal infrared imaging is that the larger the distance between sensor and target, the lower the measured temperature of the object. Consequently, a global detection rule using the mean intensity of all panels in the fault detection algorithm is not applicable. Therefore, a local detection rule was applied to automatically detect defective panels using the mean intensity and standard deviation range of each panel by array. The performance of the proposed algorithm was tested on three sample images; this verified a detection accuracy of defective panels of 97% or higher. In addition, as the proposed algorithm can adjust the range of threshold values for judging malfunction at the array level, the local detection rule is considered better suited for highly sensitive fault detection compared to a global detection rule. In this study, we used a panel area extraction method that we previously developed; fault detection accuracy would be improved if panel area extraction from images was more precise. Furthermore, the proposed algorithm contributes to the development of a maintenance and repair system for large-scale PV power plants, in combination with a geo-referencing algorithm for accurate determination of panel locations using sensor-based orientation parameters and photogrammetry from ground control points.

• Research in Plant Disease
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• v.20 no.3
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• pp.211-215
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• 2014

This research was performed to examine the protective activities of the mixtures of pine oil and copper hydroxide against bacterial spot and anthracnose on pepper plants. As for bacterial spot, the treatment of pine oil alone displayed high disease incidence (59.6%) and low protective effect (28.9%). In comparison, the treatments of mixtures and copper hydroxide alone showed protective activities of 66.8-76.1%. The mixture of pine oil and copper hydroxide (4:1) suppressed the most effectively bacterial spot on pepper. On the other hand, the mixture of pine oil and copper hydroxide (4:1) also showed the strongest protective effect against pepper anthracnose among the 4 treatments tested; its disease incidence and disease control value were 49.8% and 41.7%, respectively. The other treatments showed low protective activities with control values of 7.4-17.1%. These results suggested that the mixture of pine oil and copper hydroxide (4:1) can be used for the environmental-friendly disease control of bacterial spot and anthracnose on pepper.

• Research in Plant Disease
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• v.20 no.3
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• pp.201-205
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• 2014

Damping-off, caused by Rhizoctonia solani and Pythium ultimum, is a very important plant disease and affects seeds and seedlings of many plant species worldwide. To investigate control efficacy of Serenade formulation (1.34%, SC) against Rhizoctonia and Pythium damping-off diseases, seeds of chili pepper and cucumber were sown in soils inoculated with R. solani and P. ultimum and Serenade formulation was applied by soil-drenching with 9-, 19-, and 39-fold dilutions. Control values of Serenade formulation on Rhizoctonia damping-off of chili pepper was 58% and 29% for 9- and 19-fold dilutions, respectively. In the case of cucumber Rhizoctonia damping-off, Serenade treatments showed similar control efficacy with damping-off of chili pepper. On the other hand, control efficacy of Serenade formulation on Pythium damping-off of cucumber was less than control effects on Rhizoctonia damping-off. Only Pythium damping-off of chili pepper treated with 9-fold dilution Serenade was statistically different with untreated control. This result suggest that Serenade formulation could be effectively used for controlling Rhizoctonia and Pythium damping-off diseases.

• Korean Journal of Remote Sensing
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• v.34 no.2_2
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• pp.431-437
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• 2018

We analyzed the feasibility of detecting wave gliders moving on the sea surface using SAR images. For the experiment, a model was constructed and placed on the sea using a towing ship before and after the satellite observation time. In the acquisition of KOMPSAT-5 image, high resolution SAR data of spotlight mode was collected considering the small size of wave glider. As a result of the backscattering intensity analysis around the towing ship along with wave glider, several scattering points away from the ship were observed, which are not strong but clearly distinguished from the surrounding clutter values. Considering the distance from the center of the ship, it seems to be a signal by the wave glider. On the other hand, it is confirmed that the wave glider can be detected even at the very low false alarm rate ($10^{-6}$) of the target detection using CFAR. Although the scatter signal by the wave glider could be distinguished from the surrounding ocean clutter in the high resolution SAR image, further research is needed to determine if actual wave gliders are detected in various marine environments.

• Korean Journal of Soil Science and Fertilizer
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• v.33 no.6
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• pp.398-404
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• 2000

We examined the effect of soil:water ratio on the equivalent concentration of individual electrolyte species and the electrical conductivities (EC) of the diluted extracts of 24 soil samples (loam or silt loam) collected from rose-cultivated plastic houses to estimate the EC of saturated soil-paste extracts (ECe) from diluted soil extracts. With increasing volume ratio of water (higher dilution), the equivalent concentrations of each electrolyte species and their sum increased. The relative contribution to the EC, however, was highest for $NO_3{^-}$, irrespective of soil:water ratio. The measured ECe was 6.36 for loam and $8.09dS\;m^{-1}$ for silt loam soils and the corresponding soil:water ratio was 0.38 and 0.50, respectively. The EC_e estimated from the EC of diluted extracts at 1:1, 1:2, or 1:5 soil:water ratios using their corresponding uniform diluted factors was lower than the measured EC_e and this difference was greater with higher dilution and EC values. Therefore, the alternative diluted factors (y) for each soil: water ratio were obtained following the definition of diluted factor and were correlated significantly with volume ratios of added water (x): y=1.55x+0.5 for loam and y=1.21x+0.48 for silt loam soils. On the other hand, correlation analyses of the EC of soil extracts (y) to the volume ratio of added water (x) on log-log scale yielded linear models: logy = -0.805logx + logb, SD of slope=0.05, b=sample specific constant, n=24). With known saturation percentage of a sample representing a group and and the EC of diluted extract of a given soil, the EC_e could be predicted using the proposed logarithmic equation.

• Journal of Chest Surgery
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• v.8 no.1
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• pp.19-28
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• 1975

The thoracoscopic study was reported on 21 cases of spontaneous pneumothorax requiring surgical management, and clinical values of thoracoscopic examination on spontaneous pneumothorax were also discussed. patients were treated in the Department of .Thoracic Surgery, Hanyang University Hospital for the period of two Years from May 1972 to April 1974. For exact detection of etiologic factors on spontaneous pneumothorax, the thoracoscopic examination in the intrapleural space was performed in parallel with X-ray study. this study, the difference of diagnostic and therapeutic significance between radiological and thoracoscopic findings were observed and compared simultaneously. The results are summerized as follows: Patients age was distributed between 3 and 70 years old with highest incidence in the age group of sixty decade [33. 3%], and sex ratio of male to female was 5:2. The tuberculous processes which developed superficial subpleural layer in the lung parenchyme, on the pulmonary surface could be observed by thoracoscopic examination in a characteristic picture. detection ratio of pulmonary tuberculosis by the radiologic study to that by thoracoscopy was 8:2. The adhesion between the visceral and the parietal pleura which could possibly make a rupture of the alveola and the visceral pleura was found to be localized in a small area of the lung surface. The other part of the lung surface was free of the adhesion and, therefore, the movement of the lung took place completely without any difficulty. The ruptured orifice of the pleura and pathological changes surrounding the orifice can be detected by thoracoscopy, but not by other means such as radiologic examination. A single tuberculous bleb and multiple emphysematous blebs were found on 6 cases out of 21 cases of spontaneous pneumothorax. Among these cases, radiologic Study revealed the bleb only in one patient. On the other hand, the blebs were found in all the six patients by means of thoracoscopic examination. It gives the detection ratio of bleb by radiologic study to that by thoracoscopy was 1:6. By thoracoscopy, the rupture on the lung surface were visualized on the 10 patients out of a total of 21 patients [10 patients of visual rupture]. However, the rupture of the pleura was not observed on the rest of 11 patients even by thoracoscopic examination [11 patients of non visual rupture]. Five patients [50%] out of ten who had the visual rupture on the lung surface was required a surgical operation to remove pneumothorax. For the patients who were detected to have the visual rupture of the pleura by thoracoscopy, be considered in the early stage of closed thoracostomy. of 21 patients, 16 patients [11 patients of non visual rupture of the pleura and 5 patients of visual rupture of the pleura] who received no surgical management, were treated with closed thoracostomy with continuous suction, and the` pneumothorax was healed completely up in each cases. Therapeutic measures for the remaining 5 patients of visual rupture of the pleura who were subjected to surgical approach for radical treatment of spontaneous pneumothorax were accordingly complicated, and the following different procedures were properly indicated case by case, that is, rib resection thoracostomy, simple closure of ruptured visceral pleura, wedged resection of the lung, and lobectomy.

• Journal of Korea Water Resources Association
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• v.41 no.2
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• pp.212-228
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• 2008

Five representative reference evapotranspiration(RET) equations were selected, and these equations were compared with pan evaporation by correlation analysis. Pan coefficients were also estimated. Furthermore, five selected RET equations were compared to find the similarity among those at the 21 meteorological stations located in South Korea. Five RET equations selected from 4 different category were Penman(combination approach), FAO Penman-Monteith(FAO P-M) (single source approach), Makkink and Priestley-Taylor (radiation approach) and Hargreaves(temperature approach) equations. In this study, the geographical and topographical conditions were considered for the selection of study stations. The daily meteorological data measured from 1970 at an interval of 5 years were applied in this study. The evapotranspiration estimates obtained by applying evapotranspiration equations were evaluated with numerical and graphical methods. The correlation coefficients between pan evaporation and RET in study stations were above 0.9 indicating very high correlation; however, the slopes of the individual regression lines show the values greater or less than 1.0. Hargreaves equation(temperature approach) shows the most similar evapotranspiration estimates to those of FAO P-M equation from 12 study stations, which are located near to seashore except Daegu station. On the other hand, Priestley-Taylor equation(radiation approach) shows the most similar evapotranspiration estimates to those of FAO P-M equation from 8 study stations, which are located in inland.

• Journal of Korea Water Resources Association
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• v.42 no.2
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• pp.117-129
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• 2009

Evaporation over the world is expected to increase owing to increase in temperature by global warming. However, pan evaporation around the world has decreased in the past few decades. This study, which has been conducted in 18 meteorological gauging stations in Korean peninsula, investigates the changes in pan evaporation and climate variables such as precipitation, temperature, relative humidity, wind speed, sunshine hours, and percentage of sunshine, which can affect evaporation processes; the changes in these variables have been recorded between 1960 and 2007. At most gauging stations, pan evaporation shows statistically significant downward trends. The relative humidity, wind speed, sunshine hours, and percentage of sunshine also show downward trends. On the other hand, precipitation and temperature show upward trends. The spatial distribution of the downward trend in sunshine hours and percentage of sunshine correspond to that of the downward trend in pan evaporation. Scatter plots imply that pan evaporation has a strong positive correlation with the sunshine hours and percentage of sunshine, while it has a negative correlation with precipitation. At the Gangneung gauging station, the open water evaporation estimated using the Penman equation does not show the significant downward trend shown by pan evaporation. This result implies that pan evaporation is not a good indicator of potential or open water evaporations during the investigation of their long-term variability. Finally, this study explains the complementary relationship between pan and actual evaporations. Decreases in the pan evaporation can act as an evidence for the ever-increasing actual evaporation.

• Korean Journal of Community Nutrition
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• v.5 no.3
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• pp.493-501
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• 2000

The purpose of this study was to assess the nutritional status of iron of the elderly residing in the Jeonju area. The anthropometric parameters, nutrient intake and biochemical status of iron, were measured for 60 korean elderly(23 elderly men and 37 elderly women aged 60 - 79 years old). The level of hemoglobin(Hb), hematocrint(Hct), serum iron(Fe), total iron binding capacity(TIBC) and serum ferritin(Ferritin) were measured and transferrin saturation(TFsaturation) was calculated. Mean values of Hb, Hct, Fe, TIBC, TFsaturation and Ferritin were 14.49$\pm$0.93g/이, 42.47$\pm$2.59%, 125.48$\pm$52,.46$\mu\textrm{g}$/dl, 338.13$\pm$45.92$\mu\textrm{g}$/dl, 193.00$\pm$125.03$\mu\textrm{g}$/l in elderly men and 12.82$\pm$0.99$\mu\textrm{g}$/dl, 37.66$\pm$2.90%, 100.08$\pm$42.82$\mu\textrm{g}$/dl, 356.41$\pm$54.65$\mu\textrm{g}$/dl, and 99.35$\pm$117.22$\mu\textrm{g}$/l in elderly women, respectively. Prevalence of iron deficiency varied greatly with biochemical indices of iron. It was 13.0% when judged by Fe(60 $\mu\textrm{g}$/dl) and TFsaturation(15%) whereas 34.78% by Hct(41%) in elderly men. However 13.5% of the elderly women showed iron depletion(Ferritin<20$\mu\textrm{g}$/l) and 43.2% showed suppressed erythropoiesis with iron deficiency(TIBC>360$\mu\textrm{g}$/dl). The anemic subjects assessed with TFsaturation(<15%) represented 13.5% of the elderly women, whereas 18.9% of the subjects possessed less than 12g/dl of Hb. The Hb concentration was positively correlated with Hct(r=0.980, p<0.001), Fe(r=0.384, p<0.01) and TFsaturation(r=0.349, p<0.01). On the other hand, Ferritin concentration showed a significantly negative correlation with TIBC(r=0.349, p<0.05) and a positive correlation with TFsaturation(r=0.362, p<0.01). Major food groups of iron intake in the elderly were vegetables, cereals, and fish. The mean daily intake of iron was not significantly different between elderly men and women(12.82mg vs 10.35mg). Intake of heme iron however, was significantly higher(p<0.01) in elderly men(1.03mg) than women(0.42mg). Total absorbable iron caculated by the method of Monsen was 0.55mg, 0.40mg in elderly men and women, respectively and bioavailability of dietary iron 4.29% and 3.87%.

• Environmental and Resource Economics Review
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• v.24 no.1
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• pp.1-53
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• 2015

In environmental policy areas, a greater use of economic instruments (EIs) has recently been observed in many countries. However, EIs are heterogeneous policy tools. The textbook case of a Pigouvian tax is far from widely used, mainly due to the information requirements and other structural and institutional constraints. The successful implementation of EIs might heavily depend on pre-existing structural and institutional conditions. Moreover, these institutional conditions are particularly unfavorable in developing countries. Using a simple analytical general equilibrium model, this paper examines how these constraints affect the welfare gain from the introduction of environmental taxes in developing countries. First, this paper solves for the second-best optimal Pigouvian tax and output tax in the presence of a distortionary tax on market use of labor. The result confirms that an environmental output tax achieves a socially-efficient level of emissions in the least-cost manner only if the nature of the linkage between the tax base and the environmental damage is fixed. Second, incorporating structural and institutional constraints into the model through a set of parameter values from China and the US, this paper calculates the net welfare effects of either using the ideal Pigouvian tax or instead using an output tax. The numerical simulation results show that the net welfare gain from the use of an ideal Pigouvian tax could be more than six times larger than that of an output tax in developing countries. On the other hand, the welfare gain is only 50 percent in developed countries. This means that the potential welfare disadvantage from using output taxes instead emissions tax for environmental purposes could be much greater in the case of developing countries.