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Previous research indicates a non-monotonic effect of managerial shareholding on various issues, such as firm value, earnings quality, and debt costs. These studies tend to explain non-linearity in terms of convergence of interests and managerial entrenchment, and use non-linear specifications of managerial shareholding, such as piecewise variables, to capture the countervailing effects. However, such research has been criticized for its arbitrary construction of piecewise variables. This study examines the link between managerial shareholding and misreporting by disentangling shareholding into monetary incentives and control rights, captured using CEO stock delta and voting premium, respectively. Consistent with alignment of interests and managerial entrenchment, it provides consistent evidence that CEOs’ monetary incentives regarding shareholding are negatively associated, whereas CEOs’ voting rights are positively associated with a propensity to misreport. Further analysis indicates that managerial entrenchment arises because owner-CEOs create more favorable conditions for misreporting via the board selection process. Overall, the findings confirm the well-known non-monotonic effect of managerial shareholding with new evidence and additional insights. In particular, the results provide greater assurance of non-linearity in managerial shareholding by revealing its underlying mechanisms without using conventional piecewise variables.

In general, Internet of Things (IoT) devices collect status information or operate according to control commands from other devices. If the safety and reliability of externally accessed devices are compromised, the risk of exposure of internally collected privacy information or abnormal operation of internal devices increases. This paper proposes a method of building a safe smart home environment by pre-blocking devices that may cause a risk by performing mutual safety verification between devices prior to data transmission and reception through the Session Initiation Protocol (SIP) of the home network. Using a Samsung’s commercial smartphone, not a development board to implement the device’s own verification function, and using an open source application and a SIP server providing free service, we established a test environment that is practically applicable and proved the feasibility of the attestation operation of the device. As a result of an operation test involving the capturing of packet data on a communication channel between two devices, it was confirmed that the transmission of parameter data for the actual attestation in SIP/Session Description Protocol packets succeeded without any problems. It was also confirmed that the final verification result of the target device was correctly derived. With the proposed method, it is possible to establish a safe trust relationship between smart home devices and external smart devices or between various IoT devices while also securing the smart home environment by blocking communications with devices that intentionally seek to do harm.

Sewage treatment can remove more than 90% of microplastics, yet large amounts of microplastics are discharged into the ocean. Because microfibers (MFs), primarily generated from the washing of synthetic clothes, are the most abundant type of microplastics among various microplastics detected in the sewage treatment, reducing the amount of MFs entering these treatment plants is necessary. This study aimed to test whether the amount of MFs released from the washing process can be reduced by applying a chitosan pretreatment to the garments before washing. Before the chitosan pretreatment, the polyester clothes released 148 MFs/L, whereas 95% of MFs were reduced after the chitosan pretreatment with 0.7% of chitosan solution. The chitosan pretreatment was applied to other types of garments, such as polyamide and acrylic garments, by treating them with 0.7% of chitosan solution, subsequently, MFs reduced by 48% and 49%, respectively. A morphology analysis conducted after washing revealed that chitosan coating on the polyamide and acrylic were more damaged than on polyester, suggesting that the binding strength of polyamide and acrylic with chitosan was weaker than that of polyester garment. Thus, the results suggested that the chitosan pretreatment might be a promising solution for reducing the amount of MFs generated in the laundering process.

When phosphorus and nitrogen concentrations are high in lakes and reservoirs, enough for algae to grow, algal bloom prevention needs to be approached by circulation of stagnant water. A new circulation technology ‘Spiral vortex artificial circulation’ was developed that transports water to the surface without any hose and also provides sufficient oxygen as the water circulates. Artificial thermal and dissolved oxygen stratification was created in a water tank, and thermometers and DO meters were placed at each layer to evaluate the technology’s efficiency by comparing how fast the stratification broke. Two types of booster were used: a flow booster which promotes thorough mixing and a 12 cm flat round booster that protects the bottom of water column from disturbing, yet circulates the surface. Impeller speed was set at 60 rpm and 180 rpm to compare speed difference thus total of four experiments were conducted. The stratified water was completely mixed in two experiments with flow booster. However when 12 cm flat round booster was used at 60 rpm, even after 100 minutes of operation the stratification was not broken whereas it took 75 minutes at 180 rpm. The same or similar settings can be applied in situ without disturbing the benthic zone; if not, nutrients could be released to water bodies which might lead serious eutrophication. The further technology evaluation is in progress for improving its algal bloom suppression and energy efficiency since all technologies required to be environmentally sustainable.

The thermal performance of flat plate pulsating heat pipes (PHPs) in compact electronic devices can be improved by adopting asymmetric channels with increased pressure differences and an unbalanced driving force. The objective of this study is to investigate the heat transfer characteristics of flat plate PHPs with various asymmetric ratios and aspect ratios in the channels. The thermal performance and flow pattern of the flat plate PHPs were measured by varying the asymmetric ratio from 1.0 to 4.0, aspect ratio from 2.5 to 5.0, and heat input from 2 to 28 W. The effects of the asymmetric ratio and aspect ratio on the thermal resistance were analyzed with the measured evaporator temperature and flow patterns at various heat inputs. With heat inputs of 6 W and 12 W, the optimum asymmetric ratio and aspect ratio for the flat plate PHPs were determined to be 4.0 and 2.5, respectively. With the heat input of 18 W, the optimum asymmetric ratio and aspect ratio were determined to be 1.5 and 2.5, respectively.

This paper examines the impact of shareholder intervention on investment distortions, which we capture using overinvestment of free cash flow by overconfident CEOs. Using this definition and U.S. data for 1996–2014, our fixed effects and difference-in-difference matching estimation results provide consistent evidence that the threat of potential intervention of shareholders can curb overinvestment by overconfident CEOs. Specifically, firms with greater voting premium and hedge fund activism experience less overinvestment and exhibit lower sensitivity of free cash flow to investment. Such disciplining effects are stronger for firms managed by overconfident CEOs. Overall, our results suggest that shareholder intervention is particularly effective at mitigating overinvestment that is more likely to be distorted.

A DHP (dehumidifying heat pump) has been proposed to save energy consumption in electric vehicles during the dehumidifying and heating operation. Since the mean occupancy rate in a vehicle is less than two people, it is required to optimize the performance of the DHP at low occupancy for an effective operation. The objective of this study is to investigate the performance improvement of a DHP by using the additional waste heat source in electric vehicles with low occupancy. The experiments on the DHP were conducted by varying operating modes, according to various numbers of passengers. Even though the air source DHP in an AL (alternating) mode showed 7.6% lower heating capacity on average, compared to that in the DH (dehumidifying and heating) mode, the COP improvement of the air source DHP in the AL mode against the DH mode was approximately 31% for one passenger. In addition, the dual source DHP in the AL mode showed 15.8% higher heating capacity and 5.2% higher COP on average, compared to the air source DHP in the AL mode.

The algae bloom in river has been issued in Korea. In order to alleviate treatment load of water treatment plant and to meet water treatment capacity of the plant, a high-speed algae pretreatment methods connected with water intake pipe are required. In this study, a pilot-scale of pretreatment system was tested. It was consisted of coagulation and electro flotation processes. The algae pretreatment efficiency by the comparisons of chlorophyll-a, nutrients (total nitrogen, total phosphorous), and chemical oxygen demand (COD) concentration was evaluated. As a result, the system showed about 45% of removal efficiency by the only flotation separation without coagulation judged by chlorophyll-a concentration. On the other hand, the removal efficiency was improved with increase of coagulant dosage and electric power. It was improved to about 80% of chlorophyll-a concentration. The system could treat algae containing solution within a few minutes on the basis of residence time of flotation tank. Consequently, this study suggests that the system could be used as an algae pretreatment step in water treatment process.

Recently, environmental pollution from microplastics (MPs) has become a significant reason for increasing the number of studies to develop analysis methods. The Nile red staining method (NR-S), which is staining polymer particles with Nile red (NR) dye, has been widely used for the analysis of MPs in environmental samples. However, this method has several limitations, as it is difficult to stain MPs covered with organic matter residues. In this study, we modified the NR-S method into an NR plate method (NR-P), where the plate is coated with NR instead of staining MPs directly. The optimum concentration of NR solution was obtained (1000 mg/L), and the effectiveness of the NR-P method for the analysis of MPs was assessed using different types (polypropylene, polyethylene, polyethylene terephthalate, and polystyrene), sizes (100&ndash, 1000 &micro, m), and shapes (sphere, fiber, film, and flake) of plastic materials. The NR-P method demonstrated improved resolution in the overall types, shapes, and sizes of MPs and was better than the control (without NR plate method) and NR-S method. In particular, the NR-P method can effectively observe MPs covered with organic matter, which was a major limitation of the NR-S method. Finally, MPs in sewage field samples were analyzed by the NR-P method with an accuracy of 78% confirmed by FT-IR. We demonstrated that this method is a convenient and efficient alternative for identifying MPs, even for field samples.

Cyanobacteria frequently dominate the freshwater phytoplankton community in eutrophic waters. Cyanotoxins can be classified according to toxicity as neurotoxin (Anatoxin-a, Anatoxin-a(s), Saxitoxins) or hepatotoxin (microcystins, nodularin, cylindrospermopsin). Microcystins are present within cyanobacterial cells generally, and they are extracted by the damage of cell membrane. It has been reported that cyanotoxins caused adverse effects and they are acculmulated in aquatic oganisms of lake, river and ocean. In natural, microcystins are removed by biodegradation of microorganisms and/or feeding of predators. However, in process of water treatment, the use of copper sulfate to remove algal cells caused extraction of a mess of microcystins. Microcysitns are removed by physical, chemical and biological methods according to reports. The reduction of nutrients (N and P) inflow is basic method of prevention of cyanobacteria bloom formation. However, it is less effective than investigation because nutrients already present in the eutrophic lake. In natural lake, cyanobacteria bloom are not formed because macrophytes invade from coastal lake by eutrophication. Therefore, a coastal lake has to recover to prevent of cyanobacteria bloom formation.

The clamping force should be applied to a proton electrolyte membrane (PEM) fuel cell due to its structural characteristics. The clamping force affects the ohmic and mass transport resistances in the PEM fuel cell. In this study, the effects of the clamping force on the water transport and performance characteristics of a PEM fuel cell are experimentally investigated with variations in the relative humidity and current density. The water transport characteristics were analyzed by calculating the net drag coefficient. The ohmic resistance decreased with the increase in the clamping force due to the reduced contact resistance and more even membrane hydration. However, the mass transport resistance increased with the increase in the clamping force due to the gas diffusion layer compression. The net drag coefficient decreased with the increase in the clamping force due to high water back-diffusion. Additionally, the relationship between the total resistance and the net drag coefficient was investigated.

This research was conducted to investigate the magnitude and nature of the emission of runoff pollutants with the goal of quantifying stormwater pollutant concentrations from driveways site. A statistical summary for concentration characteristics of driveway runoff is provided based on the various analysis techniques. Runoff water qualities in temporal variation were generally higher in wet season than in dry season with a high degree of variability. The 95 % confidence intervals of washed-off pollutant concentration are ranged to 82.4-141.4 mgL -1 for TSS, 53.3-87.6 mgL -1 for Turbidity, 19.0-38.7 mgL -1 for BOD, 34.0-59.2 mgL -1 for COD, 16.4-27.4 mgL -1 for DOC, 4.3-5.6 mgL -1 for TN and 0.25-0.34 mgL -1 for TP, showing the high values based on the surface or lake quality standards in Korea. The first flush effect is mostly occurred within initial 30 min of storm duration. Concentrations of water quality constituents in urban stormwater are often expressed in probabilistic terms using statistics such as the mean and standard deviation and selected quintiles. Three probability distributions, weibull in TSS and Turbidity, lognormal in BOD and COD and gamma in DOC, TN and TP were fitted and the goodness-of-fit was assessed using the Anderson-Darling test. The correlation matrix of all water quality variables shows significant relationships between all parameters (P

In electric vehicles, air-conditioning (AC) units and electric heaters have been used for dehumidifying and heating the cabin. However, the air heating process in the electric heater causes higher power consumption due to a lower air temperature entering the electric heater from the sensible cooling in the humidifying process. In this study, a heat pump (HP) and a dual-evaporator heat pump (DHP) combined with a heater are proposed as effective dehumidifying and heating units using waste heat recovery from the dehumidifying process. The performances of the AC, HP, and DHP systems were measured and compared by varying the indoor air wet bulb temperature and compressor speed ratio. Generally, the HP and DHP systems showed superior performance to the conventional AC system in the dehumidifying and heating operation. At the indoor air wet bulb temperature of 13 °C, the DHP system showed 53% and 62% higher specific moisture extraction rate and COP, respectively, than the HP system.

A HGSHP (hybrid ground-source heat pump) is proposed to solve the performance degradation of the GSHP (ground-source heat pump) under imbalanced load conditions. The HGSHP is composed of three flow loops: a refrigerant flow loop, a GFL (ground flow loop), and a SFL (supplemental flow loop). In this study, the transient performance characteristics of the HGSHP were measured and analyzed in the cooling mode at various flow loop configurations, including the HGSHP S (HGSHP with the serial configuration) and HGSHP P (HGSHP with the parallel configuration), and GSHP. During the hybrid operation, the HGSHP S showed relatively higher COP (coefficient of performance) than the HGSHP P due to the lower heat accumulation in the ground under the degraded ground thermal condition. In addition, under the steady state condition, the COPs in the HGSHP S and HGSHP P were 15% and 7% higher, respectively, than that in the GSHP.

The objective of this study was to evaluate the separation of fine particles using several frequencies and hydraulic retention times (HRTs) in an acoustic standing wave reactor without any separate cooling devices. The acoustic standing wave reactor consisted of sufficient space (over 100 mm) between the transducer and reflector, resulting in a slight increase in temperature. However, the increase in temperature did not affect the formation of standing waves and particle aggregations in our experiments. The results indicated that the turbidity removal efficiencies of fine kaolin particles, when using frequencies of 580 kHz, 1, and 2 MHz, increased with longer standing wave operation time. Especially, the turbidity removal efficiencies for 1 and 2 MHz were higher than that for 580 kHz because the wavelength (λ) of the 580 kHz wave was longer than that of the 1 and 2 MHz waves. Furthermore, the turbidity removal efficiency of kaolin in a continuous reactor improved with increasing hydraulic retention times (HRTs), and the reactor was more effective with 1 and 2 MHz used in parallel instead of 1 and 2 MHz used individually under the same HRT conditions with the entrance length (EL) having no adverse effect.

Cultivated lands within the river district are likely non-point sources of pollution that could be directly discharged into rivers and lakes, as well as identified as significantly risky areas for pollutant run-off during floods. In this study, major non-point sources in surface run-offs, from cultivated lands within the river districts, and their effects on the bodies of water in North Han River Basin were examined. It was found that pollutant concentrations in the run-offs from farms appeared to be generally higher than in the run-offs from paddies. Initial concentrations of pollutants during rainy seasons were usually higher than the medians of their concentration ranges, though not necessarily the highest. The unit loads of BOD from cultivated lands within river districts, which were proposed in this study for the first time in Korea, were 4.56, 3.35, and 10.26 kg/km2/year for paddies, farms, and greenhouses, respectively. Likewise the unit loads of total nitrogen (TN) were proposed as 1.54, 8...

A multi-heat pump has been widely used to provide cooling and heating in a building. In addition, the demands for a cascade heat pump water heater have been increased due to its higher energy efficiency with high water temperature. In this study, a cascade multi-functional heat pump, which combines a multi-heat pump using R410A for air heating and cooling with a cascade heat pump using R134a for water heating, is considered to provide simultaneous air heating, air cooling, and water heating in a building. The performance of the cascade multi-functional heat pump was measured and analyzed in four operation modes: full-heating hot water, heating-main hot water, full-cooling hot water, and cooling-main hot water. The performance of the cascade multi-functional heat pump in each of the four operation modes was optimized by adjusting control parameters such as the compressor rotation speed and EEV opening and by modifying the refrigerant flow path.

A heat pump has been considered as an alternative to an electric heater to increase the efficiency of the heating unit in electric vehicles. However, the heating performance of a single source heat pump has yet to be improved at low outdoor temperatures. This study investigates the feasibility of a dual source heat pump using both air and waste heat in electric vehicles. The performance of the dual source heat pump was measured at various operation modes: air source-only, waste heat-only and dual heat source. The heating performance of the dual source heat pump was higher than those of the single source heat pumps. In addition, an alternating single mode operation of air source-only and waste heat-only modes was proposed to improve performance at low outdoor air temperatures.

Fluid generated within the sonic or ultrasonic waves are reflected by the wall, while the opposite direction forming a predetermined sound wave to the acoustic standing wave is referred to. In this study, the frequency of 1.0 MHz and 2.0 MHz acoustic standing wave generation module is installed in a continuous particle separation device, the laminar flow of influent, taking into account the hydraulic retention time (HRT) in accordance with changes in particle separation characteristics investigated. Operation of a standing wave in the particle separation device about temperature is increased, but did not significantly affect the formation of standing waves. During operation, the HRT 1 hr frequency 1.0 MHz 2 hr, 4 hr longer as the particle separation efficiency (turbidity) were 64.1%, 70.0%, 74.3% and, 2.0 MHz has 58.0%, respectively, depending on HRT, 61.8%, 70.7% in the respectively. That is, the same frequency, the HRT treatment efficiency is 10% or more, depending on differences in generation and, 1.0 MHz frequency, 2 hr, 2.0 MHz 4 hr at about 70% or more of the processing efficiency can be maintained. Frequency of 1.0 MHz and 2.0 MHz operation at the same time, as a result, HRT 1 hr, 2 hr, 4 hr particle separation efficiency of 63.8%, respectively, 70.6%, 77.6%, rather than the generation of standing waves appear continuous HRT is affecting a lot of particles to separate could know.

We measured chrominance of chrysotile powder using a colorimeter and a luminance meter under different light sources with seven color filters to test feasibility for the real time asbestos detector development. Chrysotile powder was prepared by heating asbestos fabric at 150 °C for 1hr and hydrochloric acid treatment was followed to remove other elements. Refractive index liquid was used as a color changing analyte to observe the change in chrominance of chrysotile. From the measurements, it revealed that a colorimeter was more suitable for the chrysotile detection by the maximum change in chrominance, especially in the short wave length range of blue regions. A luminance meter was not able to separate the difference in chrominance depending on different color and light sources regardless dyeing. It might be due to that reflected light from chrysotile particle was relatively weaker than that from illuminated area. It is our suggestion that the real time monitoring of asbestos in indoor air can be possible using a color sensor, specified to the unique wavelength of dyed chrysotile based on our chrominance data.

The purpose of this study was to remove sediments obtained from breeding ground using supersonics and micro-air flotation method. Sediments from Tongyong breeding grounds showed no contaminations of heavy metals but had great amount of organics. Thus, efficient removal of sediments was required to preserve water quality near breeding ground. Supersonics treatment for sediments was determined to be essential because higher removal efficiency of sediments was obtained when supersonics treatment was used. In addition, application of coagulants increased removal efficiency because its usage increased particle size of sediments, which enabled easy trapping of sediments particle into micro-air bubbles. Removal efficiency of sediments slightly decreased from 95.8% (1 g/L) to 83.9% (8 g/L) at the tests for different amount of sediments, but most of tiny particles were removed from water where sand size particles were left in the bottom of reactors.

A small air-conditioner or chiller for a constant temperature bath normally uses a constant speed compressor. The constant speed compressor is relatively inexpensive, but it uses on/off control for capacity modulation. The on/off control has several disadvantages, specifically energy loss and large temperature fluctuation. Continuous operation with a bypass system can be an alternative to on/off control, for capacity modulation. In this study, a heat pump system having a hot-gas bypass and a liquid bypass was adopted. The performance of the bypass-type heat pump was measured, by varying the bypass valve opening. The differences of the COP between the hot-gas bypass and the liquid bypass, in the cooling and heating operations, were within 2% and 1%, respectively. The liquid bypass showed a wider range of capacity control in the cooling operation but the hot-gas bypass showed a wider range of capacity control in the heating operation.

The high-speed algae pretreatment system consisted of coagulation and electro coagulation process was tested. This study examined algae removal efficiency by the comparison of chlorophyll-a concentration before and after treatment. As a result, the system showed about 45% of removal efficiency by the only flotation separation without coagulation. As increase of electric power and coagulant dosage, the removal efficiency was improved to about 80%. The system could treat algae containing solution with a few minutes on the basis of residence time of flotation tank. Consequently, this study suggests that the system could be used as a pretreatment step in water treatment process.

The field study was carried out to investigate runoff characteristics of non-point source (NPS) by cultivation activity in river district. Two sites were selected mainly as G region (paddy field, green house), located in Kwangju, Gyeonggi Province, and S region (ordinary field), located in Namyangju, Gyeonggi Province, those belong to Paldang reservoir watershed. The paddy field with water storage capacity showed a slow increase in runoff as rainfall intensity increases. Meanwhile, both green house and ordinary filed revealed a rapid increase. The average BOD runoff concentration of paddy field, green house, and ordinary field was 2.0 mg/L, 2.8 mg/L, 7.9 mg/L, respectively. It indicates that ordinary field shows the highest value in BOD, SS, T-N, and T-P concentration due to the soil loss during rainfall. As a result of runoff load estimation according to the field, a T-N runoff load of paddy field was 1,793.9 kg/year, higher than that of ordinary field. It was estimated that a SS runoff load of ordinary field was 69,704 kg/year and accounts for more than 70% of overall runoff load.

Due to its irregular structure, the efficiency of the pelletized fibrous filter can be improved if the target substance is line-shaped. Thus, this study was conducted to examine the applications of the pelletized fibrous filter for biological sewage water with line-shaped particles. Towards this end, the pelletized fibrous filter was applied to advanced treatments in which the particles in the sewage water in the supernatant using solid-liquid separation from the final-settling reservoir was filtered with pelletized fibrous filters. To determine the process efficiency of the filter device, a multiparameter water quality analyzer and a data transmission system were established, which showed the efficient process even at a large distance, as well as the good operational status of the filter device. The pilot plant operation results showed that the concentration of TSS in the influent at 20-75 mg/L was reduced to 0.4-10 mg/L in the processed water. The average processing efficiency was 94.9% between 71.4 and 97.9%, and particularly, that of the suspended solids was very high. The results also showed that 27.2% CODMn, 22.5% T-N, and 30.0% T-P were removed.

A simultaneous cooling and heating multi-heat pump can improve thermal comfort and energy efficiency through heat recovery at partial load conditions. The performance of a simultaneous heating and cooling multi-heat pump with four indoor units was measured by varying the compressor speed, EEV opening, and fan speed at full and partial load conditions in five operating modes. In the cooling-only and heating-only modes, the heating and cooling capacities were properly controlled by varying the compressor speed. However, in the cooling-main and heating-main modes under partial load conditions, a large imbalance between the cooling and heating capacities was observed even though the compressor speed was optimized. This capacity imbalance under partial load conditions was optimized by adjusting the EEV openings in the mode change unit and the outdoor unit. In addition, in the entire-heat recovery mode, rating compressor speed ratios were proposed under the full and partial load conditions.

In this research, micro-sized copper bump for multi-layered printed circuit board (PCB) was successfully developed using pulse-reverse electroplating method. The electroplating parameters of current density, pulse-reverse ratio and brightener content were optimized for fabrication of suitable micro-bumps. The pulse-reverse electroplated micro-bumps were characterized using various analytical tools and techniques such as optical microscopy, scanning electron microscopy, atomic force microscopy and hydraulic bulge testing. Optical microscope and scanning electron microscope analysis results indicated good electroplating uniformity in the current density range of 1.4–3.0 A/dm 2 , pulse-reverse ratio of 1:1, and brightener concentration of 600 ppm.

In case of cleaning the tap water in Korea, focus has been concentrated on how to improve water quality during the process of purification after taking in original water. However, the interest in human health has been increased, so 'secondary contamination' ,polluted in the process of crossing water reservoir, distributing pipes, indoor water tanks and water pipes after water left a filtration plant, is soared up as an important object of water quality control. Especially the copper pipe for the tap water, its characteristic was acknowledged as a pipe with many merits such as excellent corrosion resistance and easy assembly at the time to lay, is being frequently used in the advanced countries like East Europe, North America, Australia, etc, and is also being used as the material of pipe laying among the pipes for distributing water in Germany and Netherlands. But in case of Korea, the blue or green water problem is found even in the less than 6 year old copper pipes after being installed newly in indoor pipe laying for water distributing that causes to bring about aesthetic distrust to citizens, so the necessity of study is raised to control this situation. In this study tried to control the corrosion and the blue and green water problem happening in the copper pipe using corrosion inhibitors to settle down the various problems available to happen by this problem and suggested an optimized method to manage this situation.

EPP(Expanded Polypropylene) media with a large surface area was developed to treat the first flush of storm water from motorway. A series of studies have been carried out concerning the main mechanism of physical characteristics with the filtration and adsorption of EPP media in EcoTank system in order to evaluate the performance risk for treating trace metals (Cd, Cr, Cu, Pb and Zn) under uncertainty. In view of quantitative and qualitative risk analysis, this study assesses the uncertainty analysis involved in predicting of treating heavy metals from road runoff using an EcoTank system. Results of treatment performance estimation after the treatment of trace metals using an uncertainty analysis were 50.0.% probability (class 3; moderate) for Cd, 52.0% probability (class 4; high) of Cr, 47.1% probability (class 3; moderate) for Cu, 44.4% probability (class 3; moderate) for Pb and 51.2% probability (class 4; high) for Zn, respectively. The performance risk values of all the heavy metals satisfied the acceptable criteria.

With the acceleration of urbanization, impervious surface spreads due to increase of rainfall effluent; consequently, plenty of pollutants occur instantaneously, and severity of a problem caused by being worse of the river and water system is coming to the forefront. Nation Water Quality Inventory reported that 30% of the cause of water quality getting worse is caused by non-point pollutants, and 64% of the cause of polluted water quality of the lake around North Carolina is resulted from non-point pollutants of urban area. This study developed a system that treats and removes pollutants occurring in an impervious area of the urban district by using polymer media. Polymer media, made from polypropylene materials, has float ability and an irregular form. Also this study showed that polymer media has an excellent filtering function of pollutants due to porosity on the surface, and the increase of specific surface area, so that it has an excellent function to remove suspended solids (SS), organic materials and nutritive salts in effluent water on the road side. Treatment efficiency of pollutants in an impervious area of the urban district through application of polymer media to the site is 92.1% and average EMC of suspended solids (SS) is 19.74 mg/L. In addition, treatment efficiency of CODcr is 82.3%, and the efficiency of TN and TP is 50.4% and 73.9%, respectively.

The cost for nonpoint source in urban area tends to increase as it's distanced farther from the pollution source. Thus it's more effective to dispose of the pollution at the pollution source. It becomes more difficult when nonpoint source is flowed into the surface water by stormwater. In case of combined sewer, increasing stormwater on impermeable surface causes the Combined Sewer Overflows (CSOs) containing the high level of pollutants which runs into the water system through the storm overflow diverging tank without treatment process. A huge amount of CSOs is generated instantly and as it carries the pollutants on impermeable surface as well as the deposits in sewage pipe, it's necessary to develop the technology for treatment of CSOs. This study was intended to develop the solid fabric filter which will be suitable for treatment of CSOs and the characteristic and performance of solid fabric filter were evaluated.

In this study, to effectively control urban non point source pollution, natural and artificial materials which were processed in various ways were charged as a filter media in a real size urban non point source pollution plant(EcoTank) and compared and evaluated the efficiency of filtering solid and organic compounds. The efficiency of filter media was evaluated after collecting dust from urban surface and artificially producing runoffs to evaluate runoff control efficiency of pollutants that caused from pollution in urban streets. To evaluate the efficiency of pollutants runoff control depending on different filter types, EPP(Expanded polypropylene), GAC(Granular activated carbon), Zeolite, Mix-1(EPP in the upper part, GAC in the lower part), Mix-2(GAC in the upper part, EPP in the lower part) was charged to the EcoTank and conducted experiments in an identical condition[6]. As a result of the filter evaluation using real size reactor, EPP was identified as the best filter media for non point source pollution runoff control, and the efficiency was in the following order: EPP > Mix-1 > Mix-2 > GAC > Zeolite.

Joining of NiO–YSZ cermet with 316 stainless steel was carried out using B–Ni3 brazing alloy (4.5 wt% Si, 3.2 wt% B, 0.06 wt% C, 0.02 wt% P, Ni-balance, m.p. 982–1038 °C) to realize reliable sealing of the NiO–YSZ cermet anode/316 stainless steel interconnect structure in a SOFC. In the present research, interfacial (chemical) reactions during brazing at the NiO–YSZ/316 stainless steel interconnect were promoted by either of the two processing methods, (a) addition of an electroless nickel-plate to NiO–YSZ cermet as a coating or (b) deposition of titanium layer onto NiO–YSZ cermet by magnetron plasma sputtering method, with relevant process variables and procedures optimized during either of the pre-processing. Brazing was performed in a cold-wall vacuum furnace at 1080 °C under vacuum level of 10−3 Torr. Post-brazing examination of interfacial morphologies between NiO–YSZ cermet and 316 stainless steel was made using SEM and EDS. The results indicate that B–Ni3 brazing filler alloy was fused fully during brazing and continuous interfacial layer formation significantly depended on the method of pre-coating NiO–YSZ cermet. The inter-diffusion of elements was possibly promoted by titanium-deposition which reduced the diffusion reaction thickness of the interfacial area to less than 16 μm compared to 180 μm for electroless nickel-deposited NiO–YSZ cermet.