• Journal of Korean Society of Water and Wastewater
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• v.18 no.2
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• pp.113-120
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• 2004

The biodegradability of organics has become essential for the design and modeling of a biological nutrient removal process. Respirometry for the batch test just with wastewater has been conducted to estimate active biomass and readily biodegradable organics in municipal wastewater simultaneously. Municipal wastewater contains significant active biomass, which is estimated about 17% of COD. Compared to the batch test seeded with sludge, the batch test just with wastewater represents a little higher readily biodegradable organics. This might be due to the different environment of the logarithmic growth of active biomass. The nitrate uptake rate test has been also performed for the estimation of the readily biodegradable organics. The nitrate uptake rate test results in a little higher readily biodegradable organics compared to the batch test seeded with sludge and similar organics compared to the batch test just with wastewater. This might be caused by the different sludge of a sequencing batch reactor process. Taking the result of the previous research into account, the readily biodegradable, slowly biodegradable, active biomass, soluble inert, and particulate inert organics are estimated about 11%, 49%, 17%, 11%, and 12% of COD, respectively.

• Environmental Engineering Research
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• v.11 no.3
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• pp.156-163
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• 2006

In this study, substrate removal characteristics were analyzed to reduce the cost of external carbon dosage at Sudokwon Landfill Site Management Corporation in Korea by utilizing oxygen uptake rate (OUR) and nitrate uptake rate (NUR) tests. To estimate and evaluate the substrate removal characteristics obtained by the batch tests, the lab-scale MLE process was operated. By-products of J Co. (sugar manufactory) and S Co. (fine chemical industry) were selected as the concerned carbon sources through a comparison of carbon and nitrogen contents. MeOH was tested as a control experiment. Until the steady state, the fraction of $RBDCOD_{OUR}$ concentration to COD concentration of J Co., S Co. by-products and MeOH increased and reached levels of 98%, 82%, and 100%, respectively. During the 20th operating day, the fraction of $RBDCOD_{NUR}$ concentration to COD concentration was 95%, 81%, and 83%, respectively. These fractions of $RBDCOD_{NUR}$ concentration to $RBDCOD_{OUR}$ concentration increased according to acclimation periods and reached levels of 99%, 97%, and 81%, respectively, on the 20th day. The results obtained from the lab-scale MLE process operation using the concerned carbon sources as external carbon were similar to that observed by OUR and NUR tests.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.5
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• pp.480-486
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• 2006

On account of exchanging main process from chemical precipitation for MLE(Modified Ludzark-Ettinger), an external carbon source was required for supplementation of carbon source shortage that was needed biological denitrification in the S sewage treatment plant(S-STP). In this study, NUR(nitrate uptake rate), OUR(oxygen uptake rate) test and a field application test was conducted for the applicability assessment of Terephtalic acid(TPA) by-product contained about 4.7% acetate as alternative external carbon source. As the results, TPA by-product shows more rapid acclimation than methanol, 8.24 mg ${NO_3}^--N/g$ VSS/hr specific denitrification rate, 3.70 g $COD_{Cr}/g\;NO_3$ C/N ratio and 99.4% readily biodegradable COD contents. In the results of field application, the nutrient removal efficiency was high and effluent T-N concentration is 8.2 mg/L. It is concluded that TPA by-product is the proper alternative external carbon source.

• ETRI Journal
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• v.36 no.6
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• pp.942-952
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• 2014

This paper presents a novel test point insertion (TPI) method for a pseudo-random built-in self-test (BIST) to reduce the area overhead. Recently, a new TPI method for BISTs was proposed that tries to use functional flip-flops to drive control test points instead of adding extra dedicated flip-flops for driving control points. The replacement rule used in a previous work has limitations preventing some dedicated flip-flops from being replaced by functional flip-flops. This paper proposes a logic cone analysis-based TPI approach to overcome the limitations. Logic cone analysis is performed to find candidate functional flop-flops for replacing dedicated flip-flops. Experimental results indicate that the proposed method reduces the test point area overhead significantly with minimal loss of testability by replacing the dedicated flip-flops.

• Journal of Korean Society of Water and Wastewater
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• v.26 no.4
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• pp.591-598
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• 2012

Denitrification is an important biological mechanism in wastewater treatment process because this process is technically to remove nitrogen from water to air. There have been lots of study about denitrification engineering and molecular biological research about denitrifying bacteria, respectively. However, combination of these researches was unusual and rare. This study is about the correlation between quantity of denitrifying bacteria and denitrification potential, and consists of NUR batch test as analysis method of denitrification potential and quantitative molecular analysis for denitrifying bacteria. Three reactors (A/O, MLE and A/O of nitrogen deficiency) are operated to get activated sludge with various denitrification potential. All samples which were acquired from reactors were measured denitrification potential by NUR test and NUiR test. Also, Real-time PCR was conducted for quantification of denitrifying bacteria composition in activated sludge. The various denitrification potentials were measured in the reactors. The denitrifiaction potential was the highest in MLE process and the reactor of the nitrogen deficiency showed the lowest. Genomic DNA of activated sludge was obtained and consequently, real-time PCRuse the primer sets of nirK and nirS　were conducted to quantify genes involving denitrification reductase production. As the result of real-time PCR, nirK gene showed more significant influence on denitrification potential comapred with nirS gene.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.9
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• pp.926-934
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• 2006

In this study, nitrate uptake rate(NUR) and oxygen uptake rate(OUR) tests were conducted for the assessment of application of Terephtalic acid(TPA) by-product as an alternative external carbon source for sewage treatment plant(STP). With the ASM1 installed in GPS-X the substrate removal characteristic was investigated with simulation by obtained data from NUR and OUR test. As a result, the fraction of RBDCOD(readily biodegradable COD) was mort than 90% and specific denitrification rate was observed about 8.00 mg $NO_3^-$-N/g VSS/hr that was similar to conventional external carbon source. In the next step, sensitivity analysis for heterotrophic biomass in ASM1 was conducted. Optimized parameters of ${\mu}_{max,H}$, $K_s$, ${\eta}_g$, and $b_H$ were 6.60/day, 23.3 mg/L, 0.88, and 0.54/day, respectively. Then, relative mean squared error(RMSE) was reduced to about 40%. Optimized parameters value were well corresponded with the substrate removal characteristics of high maximum and final endogenous specific OUR and high specific NUR.

• Journal of Biosystems Engineering
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• v.39 no.3
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• pp.158-165
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• 2014

Purpose: The objective of this paper was to compare test standards regarding the performance and safety of agricultural tractors to identify the differences in test conditions, measurement tolerances, and test procedures. Based on the comparison, some recommendations were proposed for possible revisions or improvements to current tractor test standards. Methods: The test standards and codes of major standards development organizations (SDOs), such as the Organization for Economic Cooperation and Development (OECD), the International Organization for Standardization (ISO), the American Society of Agricultural and Biological Engineers (ASABE), EC type approval, and the board of actions of the Nebraska Tractor Test Laboratories (NTTL), were selected and analyzed. Comparison of the test standards: The ISO provides references for fuel and lubricants for tractor tests, and the OECD provides additional measurements for calculating fuel consumption characteristics during the power take-off (PTO) tests. The ISO, EC type approval, and the ASABE provide PTO protective device and the safety requirements. During drawbar power tests, seven transmission ratios are selected for fully automatic transmissions, according to the OECD. In case of hydraulic lift tests, ISO 789-2 and OECD Code 2 advise the use of a static lift force, while SAE J283 advises the use of additional dynamic lift capacity tests for a better representation of in-field operations. The OECD, the ISO, and EC type approval determine the seat index point (SIP), whereas the ASABE determines the seat reference point (SRP) for roll-over protective structure (ROPS) tests. Diversified measurement tolerances were among the braking performance test standards. The European Union (EU) has developed daily limits for vibration exposures with adaptations from ISO 2631-1. Electromagnetic compatibility evaluations are emerging of high-efficiency tractors due to the long-term conformance to electromagnetic emissions and interferences. Comparisons of tractor test standards discussed in this paper are expected to provide useful information for tractor manufacturers and standards development personnel to improve the performance and safety test standards of tractors.

• Journal of information and communication convergence engineering
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• v.21 no.1
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• pp.68-74
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• 2023

This study examines the response of users' feelings from a gender perspective toward interactive video mobile learning (IVML). An IVML prototype was developed for the Android platform allowing users to install and make use of the app for m-learning purposes. This study aims to measure the level of feelings toward the IVML prototype and examine the differences in gender perspectives, identify the most responsive feelings between male, and female users as prominent feelings and measure the correlation between user-friendly feeling traits as an independent variable in accordance with gender attributes. The feelings response could then be extracted from the user experience, user interface, and human-computer interaction based on gender perspectives using the Kansei engineering approach as the measurement method. The statistical results demonstrated the different emotional reactions from a male and female perspective toward the IVML prototype may or may not have a correlation with the user-friendly trait, perhaps having a similar emotional response from one to another.

• Parasites, Hosts and Diseases
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• v.47 no.4
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• pp.427-429
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• 2009

To establish a definite diagnosis for pulmonary hydatid disease, combination of radiology and serology is useful. In this study, 19 preoperative sera from patients with surgically confirmed pulmonary hydatidosis, 40 sera from patients with other parasitosis and pulmonary diseases, and 20 sera from healthy donors were evaluated using 4 different serological tests, i.e., the commercial ELISA (ELISA-kit) test, the ELISA (ELISA-lab) test prepared in our laboratory, the commercial indirect hemagglutination assay kit (IHA-kit) test, and the IHA test using sensitized sheep red blood cells with tannic acid (IHA-TA). The ELISA-kit was the most sensitive (84.2%) and the most specific test (100.0%). The ELISA-kit also demonstrated the highest positive (100.0%) and negative (95.2%) predictive values. The sensitivity of the ELISA-lab test, that we prepared, was found to be 73.6%, whereas the IHA-kit test and the IHA-TA test were found to be 73.6% and 68.4%, respectively. The specificity of these tests was 96.6%, 98.3%, and 83.3%, respectively. When all 4 tests were assessed together, it was found that the sensitivity had risen to 94.7%. When the ELISA-kit was assessed with the IHA-kit and IHA-TA together, it was found that the sensitivity was 89.5% and 84.2%, respectively. Likewise, the combination of the ELISA-lab and IHA-kit or IHA-TA allowed us to achieve a sensitivity of 84.2% in cases of pulmonary echinococcosis. In conclusion, the diagnosis would be imminent if least 2 tests were applied together.

• Journal of Biosystems Engineering
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• v.39 no.1
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• pp.21-33
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• 2014

Background: Significant technological development and changes happened in the tractor industries. Contrariwise, the test procedures of the major standard development organizations (SDO's) remained unchanged or with a little modification over the years, demanding new tractor test standards or improvement of existing ones for tractor performance, safety, and comfort. Purpose: This study focuses on reviewing the research trends regarding performance, safety and comfort evaluation of agricultural tractors. Based on this review, few recommendations were proposed to revise or improve the current test standards. Review: Tractor power take-off power test using the DC electric dynamometer reduced human error in the testing process and increased the accuracy of the test results. GPS signals were used to determine acceleration and converted into torque. High capacity double extended octagonal ring dynamometer has been designed to measure drawbar forces. Numerical optimization methodology has been used to design three-point hitch. Numerous technologies, driving strategies, and transmission characteristics are being considered for reducing emissions of gaseous and particulate pollutants. Engine emission control technology standards need to be revised to meet the exhaust regulations for agricultural tractors. Finite Element Analysis (FEA) program has been used to design Roll-Over Protective Structures (ROPS). Program and methodology has been presented for testing tractor brake systems. Whole-body vibration emission levels have been found to be very dependent upon the nature of field operation performed, and the test track techniques required development/adaptation to improve their suitability during standardized assessment. Emphasizes should be given to improve visibility and thermal environment inside the cab for tractor operator. Tractors need to be evaluated under electromagnetic compatibility test conditions due to large growing of electronic devices. Research trends reviewed in this paper can be considered for possible revision or improvement of tractor performance, safety, and comfort test standards.