• Journal of Positioning, Navigation, and Timing
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• v.9 no.3
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• pp.285-292
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• 2020

This paper introduces a new computational efficient Dilution of Precision (DOP)-based landmark exclusion method while ensuring the safety of the LiDAR-based navigation system that uses an innovation-based Nearest-Neighbor (NN) Data Association (DA) process. The NN DA process finds a correct landmark association hypothesis among all potential landmark permutations using Kalman filter innovation vectors. This makes the computational load increases exponentially as the number of landmarks increases. In this paper, we thus exclude landmarks by introducing DOP that quantifies the geometric distribution of landmarks as a way to minimize the loss of integrity performance that can occur by reducing landmarks. The number of landmarks to be excluded is set as the maximum number that can satisfy the integrity risk requirement. For the verification of the method, we developed a simulator that can analyze integrity risk according to the landmark number and its geometric distribution. Based on the simulation, we analyzed the relationship between DOP and integrity risk of the DA process by excluding each landmark. The results showed a tendency to minimize the loss of integrity performance when excluding landmarks with poor DOP. The developed method opens the possibility of assuring the safety risk of the Lidar-based navigation system in real-time applications by reducing a substantial amount of computational load.

• Journal of Korean Society of Water and Wastewater
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• v.23 no.4
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• pp.397-406
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• 2009

This study was conducted to monitor the floc sizes forming in the mixing zone in the water treatment plant. The dosing amount of poly aluminium chloride(PAC) was determined by particle dispersion analyzer(iPDA) in the lab and field scale test. During a field test period, PAC coagulant was used and the raw water was taken from Nakdong river. PAC wad diluted to activate the coagulant, leading to bring the more homogeneous dispersion in the shorter time. To monitor the floc sizes, the unit of floc size index(FSI) was used. With increasing of raw water turbidity, FSI value was increased. Also, the increased dosing amount of PAC brought the increased FSI and with overdosing of coagulant was in turn decreased. When the PAC was fed into the raw water after dilution in a field scale test, the width of FSI was narrower compared with the feeding of the mother liquor of PAC, implying that the formed flocs are denser and more uniform sizes. The width of FSI in average was varied on depending on the basicity of coagulant. Also, dF value, fractal dimension was evalued with the different coagulants, showing from 2.01 to 2.03. On-line floc monitor was effective for the optimal dosing in the drinking water plant.

• Food Science and Biotechnology
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• v.15 no.1
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• pp.91-95
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• 2006

Effects of cultivars, cooking, and processing on hemagglutinin activity were evaluated by observing macroscopic hemagglutination using serial twofold dilution of trypsinized human blood type-O or rabbit blood. Hemagglutinin activity was expressed as maximal geometric dilution fold. Agglutination of rabbit blood was more sensitive compared to human blood. Hemagglutinin activities of glyphosate-tolerant soybean, HS2906, and imported conventional soybeans were not statistically different, although significant differences were observed among conventional soybean cultivars cultivated in Korea (286 to 1535 HU/mg protein). Time required to reach fifty percent inhibition of hemagglutinin activity ($IT_{50}$) value decreased with increasing cooking temperature and pressure. Most effective conventional cooking method to inhibit hemagglutinin activity was pressure-cooking ($IT_{50}$: 1.36 min). Calculated activation energy based on reaction rate constant was 4.88 kcal. No hemagglutinin activities were detected in processed soybean products such as tofu, soybean paste, and soysauce.

• Biotechnology and Bioprocess Engineering:BBE
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• v.10 no.2
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• pp.115-121
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• 2005

Using a general Saccharomyces cerevisiae as a model strain, continuous ethanol fermentation was carried out in a stirred tank bioreactor with a working volume of 1,500 mL. Three different gravity media containing glucose of 120, 200 and 280 g/L, respectively, supplemented with 5 g/L yeast extract and 3 g/L peptone, were fed into the fermentor at different dilution rates. Although complete steady states developed for low gravity medium containing 120 g/L glucose, quasi-steady states and oscillations of the fermented parameters, including residual glucose, ethanol and biomass were observed when high gravity medium containing 200 g/L glucose and very high gravity medium containing 280 g/L glucose were fed at the designated dilution rate of $0.027\;h^{-1}$. The observed quasi-steady states that incorporated these steady states, quasi-steady states and oscillations were proposed as these oscillations were of relatively short periods of time and their averages fluctuated up and down almost symmetrically. The continuous kinetic models that combined both the substrate and product inhibitions were developed and correlated for these observed quasi-steady states.

• Journal of Sensor Science and Technology
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• v.30 no.5
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• pp.337-341
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• 2021

In this paper, we describe the fabrication of a paper-based enzyme-linked immunosorbent assay (ELISA) to detect polygalacturonase (PG), which is used as a biomarker to determine whether a plant is infected with a disease. The proposed paper-based ELISA can analyze the concentration of PG in a short time using a small sample compared to the traditional ELISA, which is generally performed using a well plate. To increase the resolution of the sensor, we optimized the dilution ratio of the HRP-conjugated goat anti-rabbit IgG antibody and the dilution ratio of the anti-PG and HRP-conjugated goat anti-rabbit IgG antibodies. Furthermore, for quantitative analysis of PG concentration, Delta RGB analysis was conducted to detect color changes in the sensing window displayed by the PG samples at various concentrations. Based on the experiment, the fabricated paper-based ELISA could measure at least 0.25 ㎍ of PG and the measurement range was 0.25-2 ㎍. Therefore, the paper-based ELISA for detecting PG is expected to be able to determine the presence or absence of disease in crops at the infection stage in the future.

• Particle and aerosol research
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• v.14 no.4
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• pp.191-203
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• 2018

IIn this study, we have developed drying systems for reducing the error by humidity on measuring particulate matter (PM) in the ambient air with optical particle measuring instruments. Two types of drying systems were designed: drying systems using heating and dilution methods. In addition, 3 types of drying systems using a heating method were designed: Type A (1 hole), B (3 holes) and C (7 holes). After making them, the laboratory and field tests were carried out to evaluate the developed drying systems. As a result, it was shown that the PM concentrations obtained by PM monitoring devices with drying systems agree well with that of the reference devices. Therefore, it could be concluded that the drying systems can be applied to PM monitoring devices for real-time monitoring of the ambient aerosols.

• Journal of Veterinary Clinics
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• v.22 no.4
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• pp.353-356
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• 2005

This study was performed to examine the antibacterial efecacy of topical agent extracted from Phellodendri cortex, Forsythia fructus and Glycyrrhizae radix as an alternative dermatological agent. Also, the most efficacious concentration of this agent and the skin-contact time inhibiting the vegetation of bacterial cells in various dilutions were determined. Five strains of Staphylococcus intermedius were exposed to various dilutions of this agent. The efficacy was assessed after exposure for time periods varying between 0 and 30 min. The antibacterial efficacy was shown to be the strongest at dilution of 1: 2. The number of viable organisms decreased significantly after 8 minutes of exposure time and was the smallest after 30 minutes of exposure time. This alternative dermatological agent is considered to be effective against Staphylococcus intermedius and has a potential to be a new topical agents far the treatment of pyoderma in dogs.

• Magazine of the Korean Society of Agricultural Engineers
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• v.45 no.1
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• pp.91-101
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• 2003

Boryeong Seadike located at southwestern seashore of Korean peninsula completed in 1997. Sluice gate operation can be an important factor to maintain lake water quality and reduce retaining time of pollutants within lake. The lake water quality simulation model, WASPS was adopted and tested to find out proper gate operation timing and discharge amount. From the simulation of sluice gate operation, the results showed that the later the time of discharge for loosing 1 day successively to 6 days, the better the quality of water. Discharge amount showed relatively minor changes of water quality. This means that pollutants flowed into lake from watershed do not have enough time to mix up with deep water when the gate opened at early time. About 3 days delay of discharge caused the dilution effect to stabilize the lake water quality in case of Boryeong freshwater lake.

• Journal of Magnetics
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• v.18 no.1
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• pp.1-4
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• 2013

Structural and magnetic properties of $Fe_{50}Mn_{50}$ nanocrystalline alloys prepared by the mechanical alloying technique (using commercial Fe and Mn powders as the precursors) are studied as a function of milling time, 1 hr to 48 hrs. The nano-crystallite size and shape are examined by using scanning electron microscopy (SEM). The effect of milling time on structural characterization was investigated using X-ray diffractometer (XRD) and extended X-ray absorption fine structure spectroscopy (EXAFS). Both XRD and EXAFS studies showed that the alloying process should be completed after 36 hrs milling. Concerning the magnetic behavior, the data obtained from superconducting quantum interference devices (SQUID) exhibited both magnetic saturation ($M_s$) and coercivity ($H_c$) depend strongly on the milling time, which are related to the changes in the crystallite size and magnetic dilution.

• Mycobiology
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• v.29 no.2
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• pp.90-95
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• 2001

During the study of microbial structures in root-regions of tomato and red pepper from fields, various soil-inhabiting fungi were isolated with the dilution plate technique. Among them an ascomycete, Emericellopsis mirabilis and three hyphomycetes, Gliocladium solani, Humicola veronae and Verticillium chlamydosporium are presented for the first time in Korea along with Talaromyces trachyspermus, Chaetomium globosum and Doratomyces microsporus.