• Journal of the Korean Society of Hazard Mitigation
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• v.10 no.6
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• pp.147-154
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• 2010

In this study, flood control effects for infiltration trench which is one of runoff reduction facilities were analyzed based on hydraulic experiments. Hydraulic experiments were conducted using 25 cm diameter circular pipe, and water depths for boundary conditions are 5, 10, 15, 20, 25 cm. Infiltration volume, runoff volume, runoff initiation time, final infiltration capacity and final infiltration capacity reached time etc. were measured from infiltration trench hydraulic experiment. We assumed that drainage area of each infiltration trench is $130\;m^2$ ($6.5\;m{\times}20\;m$) and calculated CN with area based on those experimental characteristics. In AMC-I condition, the calculated CN with five water depths is 84 for 2% pipe slope, 83 for 5% pipe slope. In AMC-III condition, the calculated CN is 84 for 2% and 5% pipe slope.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.8 no.1
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• pp.11-19
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• 1975

Yellow croaker, Pseudosciaena manchurica Jordan et Thompson, in the Yellow Sea and the East China Sea are subjected to be caught by trawl nets, stow nets and gill nets throughout the year. Monthly indices of population size are calculated. Mathematic models (I) were used in order to determine catchability coefficient, natural mortality, fishing mortality, coefficient coefficient of the fishing ground and dispersion coefficient from the fishing ground. The results are summarized as follows: 1971 1972 1973 $$Catchability\;coefficient\;(C)=1.9369\times10^{-5}\;7.5459\times10^{-6}\;1.2670\times10^{-5}$$ Natural mortality (M) = 0.1645 0.6152 0.4367 Population for the first half season (February 1 to May 31) 1971 1972 1973 Initial\;population=\;107,100M/T 209,100M/T 214,400M/T Dispersion=83,000' 159,700' 133,400' Natural mortailty= 4,700' 32.700' 19,100' Final population= 2,800' 4,500' 49,000' Population for the latter half season (June 1st to the following January 31st) 1971 1972 1973 Initial population= 44,500M/T 67,500M/T 83,800MT Recruitment= 19,000' 183,900' 67,100' Natural mortality= 5,900' 67,900' 38,500' Final population= 37,000' 168,300' 92,400'.

• KSBB Journal
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• v.11 no.6
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• pp.654-662
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• 1996

Bacterial strains which degrade crude oil were isolated by liquid culture from oil-spilled soil, and four isolates were selected among them. The strain Hl7-1 was finally selected after testing emulsifying activity and oil conversion rate. The strain Hl7-1 was identified as a Nocardia sp. based on the test for morphological, biochemical and physiological characteristics. It appears to be highly specialized for growth on crude oil in minimal salts medium since it showed preference for oil or degradation products as substrates for growth. It was found that it could grow on at least fifteen different hydrocarbons. The optimum cultural and environmental conditions were seeked. Cell growth and emulsification activity as a function of time were also determined. Crude oil degradation and the reduction of product peak was identified by the analysis of remnant oil by gas chromatography after 3 days of cultivation. Approximately 83% of oil were converted into a form no longer extractable by organic solvents.

• Journal of the Korean Society of Marine Environment & Safety
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• v.25 no.1
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• pp.130-137
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• 2019

In this study, a centrifugal seawater cooling pump was analyzed to investigate its cavitation behavior over different operating flow rates. 3D two-phase simulations were carried out with ANSYS-CFX commercial code. The $k-{\varepsilon}$ turbulence and Rayleigh-Plesset cavitation models were employed in the simulations. A head drop characteristics curves for three discharge rates was built based on numerical predictions. At higher flow rates, the impeller was more vulnerable to bubble cavitation. The 3 % head drop points of the pump working at 0.7Q, Q, and 1.3Q (Q: design flow rate) corresponded with NPSHa 1.21 m, 1.83 m, and 3.45 m, respectively. The volume of vapor bubbles was estimated and cavitation locations were anticipated to visualize the development of the cavity within the impeller. Moreover, the distribution of pressure coefficient and a blade loading chart are specifically presented, bringing out the harmful impacts of cavitation on the pump operation.

• The Journal of the Korea Contents Association
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• v.21 no.11
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• pp.518-527
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• 2021

This study verifies the polyphenol and flavonoid contents of a dried extract, as well as its antioxidant effect and growth inhibitory effect on cancer cells to investigate the potential of yellow cherry tomatoes as a physiologically active food material. The polyphenol and flavonoid contents were determined as 10.96 ± 1.57 and 4.12 ± 0.41 mg/g, respectively. The antioxidant activity was confirmed by measuring DPPH and ABTS radical scavenging ability, and RC50-the concentration that reduces free radicals by 50%-were determined as 490.83 ± 17.35 ㎍/mL and 355.90 ± 0.79 ㎍/mL, respectively. The dried extract showed no cytotoxicity with respect to normal hepatocytes (Chang) and no growth inhibitory activity with respect to A549 lung cancer cells, whereas dried extract showed growth inhibitory activities of 15.2% and 18.4% with respect to human cervical adenocarcinoma (HeLa) and human hepatocellular carcinoma (HepG2) cells, respectively, when treated with a concentration at 100㎍/mL. The results of this study confirm the potential of yellow cherry tomatoes as a physiologically active food material by verifying their antioxidant activity and their growth inhibitory activity with respect to cervical and liver cancer cells.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.21 no.3
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• pp.83-95
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• 2022

This paper proposes a system that performs object detection and distance estimation for application to autonomous vehicles. Object detection is performed by a network that adjusts the split grid to the input image ratio using the characteristics of the recently actively used deep learning model YOLOv4, and is trained to a custom dataset. The distance to the detected object is estimated using a bounding box and homography. As a result of the experiment, the proposed method improved in overall detection performance and processing speed close to real-time. Compared to the existing YOLOv4, the total mAP of the proposed method increased by 4.03%. The accuracy of object recognition such as pedestrians, vehicles, construction sites, and PE drums, which frequently occur when driving to the city center, has been improved. The processing speed is approximately 55 FPS. The average of the distance estimation error was 5.25m in the X coordinate and 0.97m in the Y coordinate.

• Korean Journal of Agricultural Science
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• v.50 no.4
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• pp.861-867
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• 2023

Lairages serve several functions, such as providing post-mortal inspections and providing a reservoir of animals to ensure the slaughter line runs efficiently. High stress lairage conditions can contribute to the accumulation of transport stress in pigs, causing poor pork quality and still stressed pigs at slaughter. The objective of this study was to investigate meat quality, blood profile and behavior changes according to lairage stocking density in in high temperature. Density treatments were as follows: LD, low density (lower than 0.5 m²/100 kg); ND, normal density (0.5 m²/100 kg to 0.83 m²/100 kg); HD, high density (higher than 0.83 m²/100 kg). Air temperature treatment was as follows: HT, high temperature (higher than 24℃). Pigs stocked with LD showed lower pH, WHC (water holding capacity), and higher DL (drip loss) and CL (cooking loss) than those stocked with HD. Pigs stocked with LD showed lower cortisol level than those stocked with HD. Therefore, Pigs exposed to high stock density (lower than 0.5 m²/100 kg) in high air temperature during pre-slaughter caused acute stress and lead to PSE (pale, soft, exudative) pork incidence. Based on obtained results, stocking of too high (lower than 0.5 m²/100 kg) density is generally not good for meat quality and animal welfare at high temperatures.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.31A no.1
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• pp.65-70
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• 1994

GaAs power MESFETs with 0.8$\mu$m gate lengths are fabricated using image reversal (IR) methods on the wafer with an undoped surface layer grown by MOCVD. The fabricated GaAs power MESFETs with an undoped surface layer show that an ideality factor 1.17, a built-in potential 0.83 V, a pinch-off voltage -2.7 V, a specfic contact resistance 1.21$\times$10$^{5}$ ~3.42$\times$10$^{2}$$\Omega$-cm$^{2}$ and an extrinsic g$_{m}$ = 103.5 mS/mm. The maximum RF output power densities of the 0.8$\mu$m devices are 360 mW/mm and 499 mW/mm, and power added efficiencies 29.67% and 29.05%, for the unit gate width 150$\mu$m and 200$\mu$m at 12 GHz.

• The Korean Journal of Nuclear Medicine
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• v.33 no.4
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• pp.368-380
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• 1999

Purpose: The purpose of this study was to evaluate and compare the scintigraphic findings and diagnostic accuracy of double-phase Tc-99m sestamibi scan in primary and secondary hyperparathyroidism (HPT). Materials and Methods: We retrospectively reviewed 16 cases of primary (18 lesions) and 11 cases of secondary HPT (44 lesions) who underwent Tc-99m-sestamibi scan before the surgical intervention. Scan was performed using LEM camera (Siemens, Germany) after the injection of 740MBq of Tc-99m sestamibi. Routine image consisted of baseline and 3-hour delayed images and each image was obtained using both parallel and pine hole collimator. The study population was 27 patients (male/female=5/22, age: $49.1{\pm}10.8$). Results: Eighteen lesions of primary HPT consisted of 13 adenomas and S hyperplasias, while all lesions of secondary HPT were hyperplasias. Among the case of primary HPT, we could detect all the lesions of 13 adenomas but only 2 lesions of 5 hyperplasias (40%) could be detected by double phase scintigraphy. Three cases of primary lesion showed decreased uptake in delayed images compared with baseline. The sensitivity, specificity, positive predictive value and accuracy of primary and secondary HPT were 58.8% (10/17), 83.3% (10/12), 83.3% (10/12), 75.9% (22/29), and 37.5% (15/40), 50% (2/4), 88.2% (15/17), 38.6% (17/44), respectively. Overall sensitivity, specificity, positive predictive value and accuracy were 43.9% (25/57), 75% (12/16), 86.2% (25/29), and 53.4% (39/73). There were no statistical difference between the weight of primary and secondary HPT lesion (p>0.05). Conclusion: Tc-99m sestamibi scan is fairly good modality to detect parathyroid lesion in patient with primary HPT before the surgical intervention. However, since some of cases may reveal decreased uptake in delayed image, a careful attention to the findings of baseline images may be helpful. Still the low accuracy of sestamibi scan in diagnosis of secondary HPT prohibits routine use of it for this disease.

• Journal of Aquaculture
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• v.18 no.4
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• pp.293-298
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• 2005

We examined the effects of GnRHa on expression of the gonadotropin subunit gene in the pituitary and on syn-thesis of the plasma sex steroids (testosterone and 17$\beta$-estradiol) in protandrous black porgy. Fish were injected intraperitoneally with 0.2g GnRHa/g and then both the pituitary and the plasma were sampled 0, 6, 12, 24 and 48 hours after injection. The mRNA level of the FSH subunit increased at 6 hours post-injection, while the LH mRNA levels expressed are same with or without GnRHa treatment. Also, GnRHa stimulation caused a significant increase of the plasma testosterone (T) and 17$\beta$-estradiol ($E_2$) after 24 hours. The homologies of black porgy FSH to red seabream, Pagrus majoy FSH, snakehead fish, Channa maculata FSH and striped bass, Morone saxatilis FSH were $83.3\%,\;79.2\%$ and $76.0\%$ respectively. Amino acid homology analysis using the GenBank and EMBL general searches indicated that black porgy FSH has a high homology with yellowfin seabream, Acanthopagrus latus LH ($97.7\%$ identity) and red seabream LH ($83.3\%$ identity).