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Development of Ultrasonic Sediment-level Sensor for Sewage Pipe Application (하수관 퇴적물 감지를 위한 초음파 퇴적센서 개발)

  • Park, Buem-Keun;Shin, Jeong-Hee;Paik, Jong-Hoo;LEE, Young-Jin
    • Journal of Sensor Science and Technology
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    • v.30 no.1
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    • pp.25-29
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    • 2021
  • In this study, we successfully developed a highly reliable ultrasonic sediment sensor to detect the sediment levels in sewer pipes in harsh environments. The ultrasonic transducer employed in the ultrasonic sediment sensor was designed so as to possess a simple structure. The developed sensor was carefully optimized by simulating the electromechanical characteristics, radiated sound wave pressures, and directivity via finite element analysis. It was also designed to possess a simple mounting structure minimizing the flow disturbance in a 400-mm sewer pipe; additionally, eight ultrasonic transducers were arranged in a four-channel mode, allowing for measurement of the sediment height in five easy steps. Through experimental evaluations, we verified the performance of the ultrasonic sediment-level sensor and its industrial applicability. The results suggested that although the precision value was notably low at 15 mm, the sediment detection performance was adequate; therefore, the developed sensor can potentially be used in industrial applications.

Environmental Assessment of Blasting Noise and Vibration in Residential Area

  • Kim, Jang-Ho;Seo, Seok-Jin;Son, Joo-Young;Sung, Han-Ki;Park, Dong-Hoon;Kim, Suck-Taek;Park, Won-Chul
    • Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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    • v.3 no.1
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    • pp.75-80
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    • 1999
  • An investigation of noise and vibration caused by the reclamation of the foreshore around J village resulted in noise measurements of 56-84 dB at the first point, 62-81 dB at the second point, and 68-78 dB at the third point. These measurements were higher than the standard level of environmental noise that is 55 dB at noon and 45 dB at night. The vibration measurements were 61-83 dB at the first point, 63-88 dB at the second point, and 58-77 dB at the third point. These measurements were also higher than the standard level of environmental vibration that is 60 dB at noon and 54 dB at night. The measurements of scattering dust were 80 $\mu\textrm{g}$/$\textrm{m}^3$ at the first point, 120 $\mu\textrm{g}$/$\textrm{m}^3$ at the second point, and 169 $\mu\textrm{g}$/$\textrm{m}^3$ at the third point. These measurements were lower than the standard level of environmental dust that is 300 $\mu\textrm{g}$/$\textrm{m}^3$/day. Although the maximum vibration level was higher than the standard level of environmental vibration, it had no influence on the construction.

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Hypoglycemic activity of diospyros peregrina fruits in diabetic rats

  • Dewanjee, Saikat;Maiti, Anup;Kundu, Mintu;Mandal, Subhash C
    • Advances in Traditional Medicine
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    • v.8 no.3
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    • pp.279-285
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    • 2008
  • Diospyros peregrina Gurke. (Ebenaceae) is a small middle sized tree grows luxuriantly in the plains of costal West Bengal, India. The objective of the study was to explore the antidiabetic activity of methanol extract of matured fruits of Diospyros peregrina to substantiate the folklore claim of traditional practitioners. It was also aimed to establish correlation with reduction of oxidative state associated with diabetes. Methanol extract of matured fruits of Diospyros peregrina was administered orally at doses of 150 and 300 mg/kg body weight for 12 consecutive days to normal and streptozotocin induced diabetic rats. Fasting blood glucose level was estimated in both normal and diabetic rats while serum lipid profiles, liver glycogen level and pancreatic thiobarbituric acid reactive substances (TBARS) were evaluated for diabetic rats. Initial and final changes in body weight were also recorded. Oral glucose tolerance test was performed during the course of study. Experimental findings showed significant antidiabetic potential of extract in term of reduction of fasting blood glucose level of both normal and diabetic rats. It was found that extract at the dose of 300 mg/kg body weight is more effective and percentage reduction (55.64) of elevated blood glucose level is comparable to that of standard drug glibenclamide (60.60) at a dose of 10 mg/kg body weight. Observed data found statistically significant in reduction of serum lipid and pancreatic TBARS levels whilst improvement was observed in liver glycogen level and body weight profiles in extract treated diabetic rats.

High-level dietary crude protein decreased backfat thickness and increased carcass yield score in finishing Hanwoo beef cattle (Bos taurus coreanae)

  • Jeon, Seoyoung;Lee, Mingyung;Seo, Jakyeom;Kim, Jeong-Hoon;Kam, Dong-Keun;Seo, Seongwon
    • Journal of Animal Science and Technology
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    • v.63 no.5
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    • pp.1064-1075
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    • 2021
  • Recently, a high level of dietary crude protein (CP) has become of interest as a possible practice to improve the carcass quality of beef cattle, and its level has been increasing in the field. However, there is little scientific evidence that supports this. This study was conducted to test whether a high dietary CP level would improve growth performance, body metabolism, and carcass traits in Hanwoo beef cattle. A total of 32 Hanwoo finishing beef cattle (18 multiparous cows, six heifers, and eight steers) participated in a 12-weeks feeding trial. Two kinds of total mixed rations were prepared to contain two different CP; 156 g/kg for the control (CON) and 173 g/kg of CP for the treatment (HCP), while maintaining a similar level of metabolizable energy. The experiment was ended when more than half of the steers reached the target body weight (730 kg). Blood was collected at the end of the experiment. After harvesting, the carcass trait was evaluated at the slaughterhouse according to Korean standards. The carcass yield score and grade were also calculated based on revised criteria. Overall, dry matter intake, average daily gain, blood metabolites concentration, and the carcass traits, except for backfat thickness and the yield score, did not differ between the treatments. The HCP had lower backfat thickness than those of CON. There was no difference in the carcass yield grade, but the yield score was higher in the HCP treatment. According to the newly revised carcass grading criteria, both yield score and grade were higher in HCP than in CON. Increasing CP supply decreased the carcass's backfat thickness without altering growth performance and body metabolism, resulting in improved yield score and grade. Therefore, feeding a high CP diet may be beneficial in the farm income, although it may also increase feed cost and nitrogen excretion to the environment.

Germination Rate and Radicle Growth Inhibition in Crops by Total Petroleum Hydrocarbons (TPH) (Total petroleum hydrocarbon에 의한 작물의 발아 및 유근생장 저해)

  • Lim, Sung-Jin;Kim, Jin-Hyo;Choi, Geun-Hyoung;Kwon, Yu-Bin;Kim, Doo-Ho;Park, Byung-Jun
    • Korean Journal of Environmental Agriculture
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    • v.32 no.4
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    • pp.273-278
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    • 2013
  • BACKGROUND: Total petroleum hydrocarbons (TPH), which are main materials of soil contamination by oil, are a term used for any mixture of hydrocarbons. Korea Ministry of Environment established the maximum permissible level of TPH in farmland by 500 mg/kg, and reported that the TPH level of soil in 266 installation such as gas station, transport company, and military unit ranged from 1,356 to 55,117 mg/kg and were much higher than the maximum permissible level in 2011. METHODS AND RESULTS: To determine the effect of TPH on crops, we investigated the effect of gasoline, kerosene, and diesel on the germination and radicle growth of mainly consumed crops. The germination rates of control in investigated all crops ranged from 80.0-100%. The germination and radicle growth in majority of investigated crops were not inhibited even at 2,500 mg/L. However, germination in onion, leek, and green perilla and radicle growth in leek, rape, tomato, and green perilla were significantly inhibited by increasing concentrations of gasoline, kerosene and diesel treatment. Germination and radicle growth inhibition of green perilla by kerosene and diesel were the highest, the percent inhibition at the 500 mg/L were 100 and 98.6%, 100 and 88.2%, respectively. 50% inhibition of germination in green perilla by kerosene and diesel were 39.96 and 29.87 mg/L, and 50% inhibition of radicle growth were 52.76 and 177.96 mg/L, respectively. Conclusion(s): These results suggest the possibility that the maximum permissible level of TPH might to be established general level with exception by crops.

Removal of Fecal Indicator Bacteria from Bivalves under Natural and Electrolyzed Water (패류 중 자연정화 및 인공정화에 의한 위생지표세균의 변화)

  • Oh, Eun-Gyoung;Yoo, Hyun-Duk;Yu, Hong-Sik;Ha, Kwang-Soo;Shin, Soon-Bum;Lee, Tae-Seek;Lee, Hee-Jung;Kim, Ji-Hoe;Son, Kwang-Tae
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.45 no.1
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    • pp.11-16
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    • 2012
  • In coastal areas that are affected by continuous, seasonal or occasional pollution sources, bivalves accumulate biological contaminants such as pathogenic bacteria. We investigated the effect of natural seawater relaying and electrolyzed seawater depuration on the bacteriological quality of artificially contaminated oysters Crassostrea gigas and short-necked clams Ruditapes philippinarum to suggest an alternative method of shellfish sanitation control.When artificially contaminated oysters and short-necked clams (fecal coliform level 1,700 MPN/100 g) were relayed into a sea area of safe bacteriological water quality, the fecal coliform level dropped to below 110 MPN/100 g after 1 day. The bacteriological quality of oysters and short-necked clams that are contaminated at a fecal coliform level of 1,700 MPN/100 g could be improved, and become appropriate for raw consumption by a single day relay under proper environmental conditions. When artificially contaminated oysters (fecal coliform level 330 MPN/100 g) were depurated with electrolyzed seawater, 94% of fecal coliform was eliminated after 12 h and fecal coliform was undetectable after 24 h. After 24 h depuration with electrolyzed seawater, the fecal coliform level of short-necked clams with initial fecal coliform of 2,400 MPN/100 g was below 20 MPN/100 g. However, the fecal coliform level of short-necked clams with initial fecal coliform of 17,000 MPN/100 g was relatively high, at 790 MPN/100 g, even after 24 h of depuration with electrolyzed seawater, because of the repeated cycle of excretion and accumulation of fecal coliform in shellfish tissue under the closed depuration environment. Such natural seawater relaying and electrolyzed seawater depuration can be restrictively applied to improve or secure the bacteriological quality of oysters and short-necked clams in accordance with safety levels for bivalves for raw consumption.

Current Uniformity Enhancement for AMOLED Data Driver IC

  • Bae, Han-Jin;Bae, Joon-Ho;Choi, Byong-Deok;Kwon, Oh-Kyong
    • 한국정보디스플레이학회:학술대회논문집
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    • 2005.07b
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    • pp.1436-1439
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    • 2005
  • A novel current-type data driver for active matrix organic light emitting diode (AMOLED) is proposed for current uniformity enhancement among its output channels. New architecture is composed of shadow DACs that precharge output stages, a single-real DAC that correct the output level to a real target current level and output stages that operate in 3 states of sampling, correcting and driving. Simulation results show that the proposed driving method and circuits improve the current uniformity among output channels of a current-type driver IC.

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Protective Effect of Methanol Extract of Swietenia macrophylla Seeds on Oxidative States Associated with Streptozotocin Induced Diabetic Rats

  • Maiti, Anup;Dewanjee, Saikat;Kundu, Mintu;Mandal, Subhash C.
    • Natural Product Sciences
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    • v.13 no.4
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    • pp.295-299
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    • 2007
  • The methanol extract of seeds of Swietenia macrophylla King. (MESM) was studied for its antidiabetic activity in streptozotocin induced diabetic rats. It was principally aimed to correlate the efficacious role of MESM on reduction of oxidative state associated with diabetes. The extract was found to be potent antidiabetic evidenced by significant reduction of blood glucose level in diabetic rats (47.96% reduction of blood glucose level, at 300 mg/kg, on day 10). It was found that, MESM at 300 mg/kg, significantly decreased TBARS (35.03 and 22.22%) whilst increased GSH (86.75 and 31.45%), SOD (93.05 and 45.88%) and CAT (56.99 and 68.46%) levels in liver and kidney respectively in diabetic rats.

Anatomical Repair of Congenitally Physiologically Corrected Transposition with Dextrocardia, Situs Inversus and the Interruption of Right Pulmonary Artery. (우폐동맥단절과 우심증을 동반한 완전내장역위 수정대혈관전위의 해부학적 교정)

  • Kim, Si-Ho;Park, Young-Hwan;Lee, Sak;Cho, Bum-Koo
    • Journal of Chest Surgery
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    • v.33 no.12
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    • pp.959-962
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    • 2000
  • A 4-year and 11-month old child was diagnosed as having dextrocardia, pulmonary atresia, atrioventricular discordance, aorta from right ventricle, PDA, the interruption of right pulmonary artery and postoperative state of Blalock-Taussing shunt on right pulmonary artery. Anatomical repair so called \"double switch operation\" was performed; the Ratelli procedure on ventricular level and the Mustard procedure on atrial level. We report the successful anatomical repair of congenitally Physiologically Corrected Transposition even with Dextrocardia, Situs Inversus and the interruption of Right Pulmonary Artery.ry Artery.

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