• Journal of Bio-Environment Control
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• v.22 no.3
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• pp.202-208
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• 2013

This study was conducted to investigate the effect of delayed controlled atmosphere (CA) storage on fruit quality and the incidence of storage disorders during CA storage of 'Fuji' apples (Malus x domestica Borkh.). In the first year of experiment, 'Fuji' apples showed 40% of watercore disorder at the commercial harvest time (Oct. 22). Twenty days delayed CA storage caused to develop the incidence of flesh browning while 30 days delayed CA storage did not. In the second year of experiment, watercore was increased with delaying harvest time. As the estabilishment of delayed CA storage was delayed, the incidence of flesh browning increased at 10 to 30 days delayed CA storage but 40 days delayed CA storage did not have any flesh browning incidence. Respiration rate increased with extending the storage duration. Delayed CA storage reduced respiration rate but was not different compared to the rapid CA. Ethylene production rate was lower in delayed CA storage than in cold storage but higher in delayed CA storage, compared to rapid CA storage. Titratable acidity was lower in delayed CA storage as CA storage progressed. Firmness was not different between rapid CA storage and delayed CA storage after 8 months of CA storage. Therefore, the results indicate that delayed CA storage should be a promising approach to reduce the risk development of flesh browning and watercore during CA storage of 'Fuji' apples.

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.117.2-117.2
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• 2011

Since Gratzel and co-workers developed a new type of solar cell based on the nanocrystalline TiO2 electrode, dye-sensitized solar cells (DSSCs) have attracted considerable attention on account of their high solar energy-to-conversion efficiencies (11%), their easy manufacturing process with low cost production compared to conventional p-n junction solar cells. The mechanism of DSSC is based on the injection of electrons from the photoexcited dye into the conduction band of nanocrystalline TiO2. The oxidized dye is reduced by the hole injection process from either the hole counter or electrolyte. Thus, the electronic structures, such as HOMO, LUMO, and HOMO-LUMO gap, of dye molecule in DSSC are deeply related to the electron transfer by photoexcitation and redox potential. To date, high performance and good stability of DSSC based on Ru-dyes as a photosensitizer had been widely addressed in the literatures. DSSC with Ru-bipyridyl complexes (N3 and N719), and the black ruthenium dye have achieved power conversion efficiencies up to 11.2% and 10.4%, respectively. However, the Ru-dyes are facing the problem of manufacturing costs and environmental issues. In order to obtain even cheaper photosensitizers for DSSC, metal-free organic photosensitizers are strongly desired. Metal-free organic dyes offer superior molar extinction coefficients, low cost, and a diversity of molecular structures, compared to conventional Ru-dyes. Recently, novel photosensitizers such as coumarin, merocyanine, cyanine, indoline, hemicyanine, triphenylamine, dialkylaniline, bis(dimethylfluorenyl)-aminophenyl, phenothiazine, tetrahydroquinoline, and carbazole based dyes have achieved solar-to-electrical power conversion efficiencies up to 5-9%. On the other hand, organic dye molecules have large ${\pi}$-conjugated planner structures which would bring out strong molecular stacking in their solid-state and poor solubility in their media. It was well known that the molecular stacking of organic dyes could reduce the electron transfer pathway in opto-electronic devices, significantly. In this paper, we have studied on synthesis and characterization of dendritic organic dyes with different number of electron acceptor/anchoring moieties in the end of dendrimer. The photovoltaic performances and the incident photon-to-current (IPCE) of these dyes were measured to evaluate the effects of the dendritic strucuture on the open-circuit voltage and the short-circuit current.

• Asian Journal of Atmospheric Environment
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• v.12 no.3
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• pp.232-243
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• 2018

The construction, development and maintenance of an economically, environmentally and socially sustainable campus involves the integration of measuring tools and technical information that invites and encourages the community to know the actual state to generate positive actions for reducing the negative impacts over the local environment. At the Universidad Nacional de Colombia - Campus $Bogot{\acute{a}}$, a public area with daily traffic of more than 25000 people, the Environmental Management Bureau has committed with the monitoring of the noise pollution and air quality, as support to the campaigns aiming to reduce the pollutant emissions associated to the student's activities and campus operation. The target of this study is based in the implementation of mobile air quality and sonometry monitoring equipment, the mapping of the actual air quality and noise pollution inside the university campus as a novel methodology for a sub-area inside a megacity. This results and mapping are proposed as planning tool for the institution administrative sections. A mobile Kunak$^{(R)}$ Air & OPC air monitoring station with the capability to measure particulate matter $PM_{10}$, $PM_{2.5}$, Ozone ($O_3$), Sulfur Oxide ($SO_2$), Carbon Monoxide (CO) and Nitrogen Oxide ($NO_2$) as well as Temperature, Relative Humidity and Latitude and Longitude coordinates for the data georeferenciation; and a sonometer Cirrus$^{(R)}$ 162B Class 2 were used to perform the measurements. The measurements took place in conditions of academic activity and without it, with the aim of identify the impacts generated by the campus operation. Using the free code geographical information software QGIS$^{(R)}$ 2.18, the maps of each variable measured were developed, and the impacts generated by the operation of the campus were identified qualitative and quantitively. For the measured variables, an increase of around 21% for the $L_{Aeq}$ noise level and around 80% to 90% for air pollution were detected during the operation period.

• The Korean Journal of Physiology
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• v.9 no.2
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• pp.7-15
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• 1975

The maximum breathing capacity (MBC) and the maximum mid-expiratory flow rate (MMF) are widely used in evaluation of the ventilatory function, among various parameters of pulmonary function. The MBC volume is the amount of gas which can be exchanged per unit time during maximal voluntary hyperventilation. Performance of this test, unlike that of single breath maneuvers, is affected by the integrity of the respiratory bellows as a whole including such factors are respiratory muscle blood supply, fatigue, and progressive trapping of air. Because of this, the MBC and its relation to ventilatory requirement correlates more closely with subjective dyspnea than does any other test. The MMF is the average flow rate during expiration of the middle 50% of the vital capacity. The MMF is a measurement of a fast vital capacity related to the time required for the maneuver and the MMF relates much better to other dynamic tests of ventilatory function and to dyspnea than total vital capacity, because the MMF reflects the effective volume, or gas per unit of time. Therefore, it is important to have a prediction formula with one can compute the normal value for the subject and the compare with the measured value. However, the formulas for prediction of both MBC and MMF of the Korean children and adolescents are not yet available in the present. Hence, present investigation was attempt to derive the formulas for prediction of both MBC and MMF of the Korean children and adolescents. MBC and MMF were measured in 1,037 healthy Korean children and adolescents (1,035 male and 1,002 female) whose ages ranged from 8 to 18 years. A spirometer (9L, Collins) was used for the measurement of MBC and MMF. Both MBC and MMF were measured 3times in a standing position and the highest values were used. For measurement, the $CO_2$ absorber and sadd valve were removed from the spirometer in order to reduce the resistance in the breathing circuit and the subject was asked to breathe as fast and deeply as possible for 12 seconds in MBC and to exhale completely as fast as possible after maximum inspiration for MMF. During the measurement, investigator stood by the subject to give a constant encouragement. All the measured values were subsequently converted to values at BTPS. The formulas for MBC and MMF were derived by a manner similar to those for Baldwin et al (1949) and Im (1965) as function of age and BSA or age and height. The prediction formulas for MBC (L/min, BTPS) and MMF (L/min, BTPS) of the Korean children and adolescents as derived in this investigation are as follows: For male, MBC=[41.70+{$2.69{\times}Age(years)$}]${\times}BSA$ $(m^{2})$ MBC=[0.083+{$0.045{\times}Age(years)$}]${\times}Ht$ (cm) For female, MBC=[45.53+{$1.55{\times}Age(years)$}]${\times}BSA$ $(m^2)$ MBC=[0.189+{$0.029{\times}Age(years)$}]${\times}Ht$ (cm) For male, MMF= [0.544+{$0.066{\times}Age(years)$}]${\times}Ht$ (cm) For female, MMF=[0.416+{$0.064{\times}Age(years)$}]${\times}Ht$ (cm)

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.2
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• pp.58-65
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• 2020

3D Models of offshore plant piping materials designed by 3D CAD systems are provided to the production processes in the form of 2D piping drawings and 2D piping installation drawings. In addition to the standard engineering information, the purchasing, procurement, manufacturing, installation, and inspection of raw materials are managed systematically in an integrated process control system. The existing integrated process management system can help reduce the processing time by managing the flow and progress of resources systematically, but it does not include 3D design model information. Hence, it is difficult to understand complicated pipe structures before installing the pipe. In addition, when design changes or immediate design modifications are required, it is difficult to find related data or exchange information quickly with each other. To solve this problem, an offshore plant-piping process-monitoring system was developed based on a 3D model. The 3D model-based piping monitoring system is based on Visual Studio 2017 C# and UNITY3D so that the piping-process work information can be linked to the 3D CAD model in real time. In addition, the 3D model could check the progress of the pipe installation process, such as block, size, and material, and the progress of functional inspection items, such as cleaning, hydraulic inspection, and pneumatic inspection.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.8
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• pp.839-846
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• 2008

The flocculation characteristics of polyacrylamide base flocculants were estimated to reduce the moisture content of the dehydrated cakes. The dewaterability for sewage sludge was found to have a marked effect depending on the flocculant type, agitating speed and time, kind of dissolution water, etc. The optimal agitating speed and time were 700 rpm and 3 sec, respectively, in this experimental condition. and the dewaterability was proportion to the agitating speed upto 700rpm. When recycle water as the dissolution water was used, the solution viscosity of all kind of flocculants was decreased. However, the change of its viscosity are not proportioned to the dewaterabilities for each flocculant. Flocculation system of combinations of the first and sencond flocculation using single flocculant was investigated. Effects of the ratio of first and second dosage for dual flocculation on the dewaterability were also investigated. The optimum conditions of dual flocculation system are 75% and 50% as first dosages for low and high viscous flocculant for total dosage of common flocculation, respectively. Based on the results, an overall mechanism of dual flocculation system is proposed and it is envisaged that optimization of flocculation processes in this way can result in considerable savings in cost.

• Korean Journal of Poultry Science
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• v.33 no.4
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• pp.263-271
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• 2006

This experiment was conducted to evaluate the effects of dietary Hwangto on growth performance and body composition in broiler chicks. A total of 216 one-day old 'Ross' broilers were assigned to 6 treatments in a completely randomized design. The six dietary treaoents were control no Hwangto added and diets containing 0.5, 1.0, 2.0, 4.0 and 8.0% of Hwangto supplementation. The weight gain of broilers tended to reduce with increasing level of Hwangto. However, there were no significant differences in feed intake and feed conversion ratio of broilers fed control and diets containing different level of Hwangto supplementation (P>0.05). There were no significant differences in TBA value of meat from broilers fed control and Hwangto supplemented diets (P>0.05). The meat cholesterol content was significantly lower in Hwangto treatment than of the control (P>.0.05). $NH_3$ concentration in feces was reduced in all Hwangto treatments (P<0.05). The Mg and Mn concentrations of meat we.e significantly higher in 8.0% Hwangto treatment than that of the control (P<0.05). The large intestine weight was significantly reduced in 2.0, 4.0 and 8.0% treatments (P<0.05).

• Journal of Bio-Environment Control
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• v.21 no.2
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• pp.140-146
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• 2012

The commercial product "pyto-patch" prepared as nano sized silver particle less than 5 nm, has effective antifungal activity against Collectotrichum gloeosporioides, Botrytis cinerea, Sclerotinia sclerotiorum in vitro. As a fungal growth inhibiton mechanism, it can reduce spore germination rate and mycelial growth. As s promising fungicide, Phyto-patch can control anthracnose effectively. The spore of C. gloeosporioides dipped in 5 ppm phyto-patch dilute suppressed germination rate to 13.2%, and mycelial growth stopped for 15 days at 10 ppm. The spore postinoculated on 10 ppm phyto-path smeared PDA surface could not germinate for 3 days and prohibit pathogen infection effectively. In field test, the anthracnose development of 4 ppm phyto-patch treated plot was less than 7% after 21 days compaired to 40% of it in untreated plot. In heavy rainfall season, pepper anthracnose effectivly contrrolled by regular 10 ppm phytopatch spraying every 7 days. The diseased pepper fruit decreased to 5.8% compaired to 94.6% in untreated plot. During drying period, the diseased pepper fruit havested in phyto-patch treated plot was 24.2%, but pepper fruit havested in untreated plot destroyed to 100% within 3 days. The nano silver particle coated on multching textile prevented late blight of pepper effectively and disease occurance delayed about month.

• Preventive Nutrition and Food Science
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• v.4 no.2
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• pp.130-133
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• 1999

Body fat-reducing ability of oyster mushroom (Pleurotus ostreatus) water extract (OMWE) was investigated of mice by supplying it drinking water. OMWE(2.95% solid content ) was prepared by extracting a low grade of the mushroom at 12$0^{\circ}C$ for 10min. The solid material of OMWE was composed of 65.2% reducing sugar, 0.23% crude fat, 0.5%total protein, 1.2% ash and 32.9% others. OMWE was appropriately diluted with drinking water. Seventy two male ICR mice(25$\pm$1 g, 7~8 weeks of age, 6 mice/cage, 18 mice/treatment) housed in polycarbonate cages containing $\beta$-chips were adopted in a temperature-and humidity-controlled facility with free access to water and diet. One week later, the mice were subjected to one of the treatments for 36days : 0 (control), 10, 50 and 100% OMWE. Drinking wter with or without OMWE was supplied twice (40ml each, 80ml in total ) daily per cage. Body weight and fed intake were recorded every three days. At the end of the experiment, mice were sacrificed to determine the chemical composition (fat, protein, ash and water). Body weight of mice treated with OMWE (10, 50 and 100%) at day 36 was 35.9, 35.9and 35.5g per mouse , respectively, and not significantly reduced as compared to that (36.5g/mouse) of control mice. Average body fat of 0,10,50 and 10% OMWE -treated mice was 14.3, 13.1, 10.7 and 12.0% , respectively. Body fat reduction by 50% OMWE treatment was 25.2% (p<0.05) relative to control. OMWE did not affect feed intake. The contents of body protein and ash were increased with respect to body fat decrease, while water content was not changed much. These results suggest that OMWE could reduce body fat of the mice without body weight change, giving the best effect by 50% OMWE.

• Journal of the Korean Recycled Construction Resources Institute
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• v.12 no.2
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• pp.196-205
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• 2024

In this study, sample collection and quantification analysis of Tire and Road Wear Particles (TRWP) from the road surface were conducted to predict the amount of TRWP generated on the road surface moving by environmental compartment depending on rainfall intensity. Samples were collected from TRWP remaining on the road surface two days after the 3 days average rainfall (0-60 mm/day) occurred and the road surface was completely dry. Only TRWP were separated from the collected samples through size and density separation, and the difference in the content of TRWP remaining on the road surface after rainfall was based on the value of 60.2 g o f TRWP o n a day witho ut rain (0 mm/day). By calculating, it was co nfirmed that 0-49.4 g o f TRWP can mo ve to the environmental compartment depending on the intensity of rainfall. In addition, it was confirmed that when the rainfall intensity was 60 mm/day, the amount of TRWP moving to each environmental section was 3.75 times higher compared to 5 mm/day, and using the results of previous research, the total amount of TRWP that can be transported to the environmental compartment by rainfall from the domestic road environment annually is 9,592 tons, and 288 tons of this can be affected by marine microplastics. However, this study has limitations in terms of limited space and predicted results, but it would like to mention the need to improve the domestic road environment and sewage treatment system to reduce TRWP. In the future, we plan to conduct sample collection and concentration analysis studies of TRWP in real environmental compartments to verify the results of this study.