• Title/Summary/Keyword: center loss

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A Numerical Study on the Efficiency of an Industrial Furnace for Oxygen Combustion Conditions (산소부화용 공업로의 운전조건이 열효율에 미치는 영향)

  • Kim, Kang-Min;Lee, Yeon-Kyung;Ahn, Seok-Gi;Kim, Gyu-Bo;Yoo, In;Jeon, Chung-Hwan
    • Journal of Energy Engineering
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    • v.24 no.3
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    • pp.82-88
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    • 2015
  • After a reheating furnace installation, the modification of the size and the heat capacity is very difficult. Therefore, the development of design package tool is required for the computation on the correct specifications before the design and the installation. Prior to development of the design tool, a module that calculates the amount of heat loss of each part according to the specifications for determining the thermal efficiency of a continuous heating furnace was developed and applied to the oxy-fuel industrial furnace. Through this, the effects of fuel type, oxygen fraction and recirculation on the efficiency of the furnace of which the output is 110Ton/hour were analyzed. In oxy-fuel combustion condition, the efficiency was 15% higher than air combustion conditions. With the using COG(Coke Oven Gas) instead of LNG, the efficiency was slightly increased. In the air combustion condition, the efficiency was increased about 33% with the preheated air. But, in oxy-fuel condition, the amount of exhaust gas was reduced, so the efficiency was increased about 7%.

Development of Effective Screening Method for Efficacy Test of Trunk Injection Agents Against Pine Wood Nematode, Bersaphelenchus xylophilus in Japanese Black Pine, Pinus thunbergii (곰솔(Pinus thunbergii)에서 소나무재선충(Bersaphelenchus xylophilus) 나무주사 약제의 효율적인 평가법 개발)

  • Shin, Won Sik;Jung, Young Hack;Lee, Sang Myeong;Lee, Chae Min;Lee, Chang Joon;Kim, Dong Soo;Mun, Il Sung;Lee, Dong Woon
    • The Korean Journal of Pesticide Science
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    • v.19 no.4
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    • pp.440-449
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    • 2015
  • Pine wood nematode (PWN), Bursaphelenchus xylophilus is one of the most serious pests of pine tree. Trunk injection of some nematicides in tree is well known as an effective control method. However there are some limitating factors which hindering the efficacy of trunk injection in field or potted tree. In this study we suggested easy and useful alternative screening methods of nematicides against PWN. Reproduction of PWN was influenced by tree twig moisture (high reproduction in high moisture trig) and paraffin coating was 78.6% reduced moisture loss in tested twig. There were no reproduction different in up and down site from infection site of twig at 1 month after inoculation of PWN and also distance (5 and 10 cm) from inoculation site of PWN did not influence the reproduction of PWN. Numbers of reproduced PWN were higher with decreasing diameter of twig. Numbers of reproduced PWN were similar to P. thunbergii and P. densiflora. However reproduction was increased depending on high inoculation density and longer propagation period. When inoculation of PWN on cut twig injected with emamectin benzoate 2.15% EC and morantel tartrate 8% SL in trunk of Pinus thunbergii in the field, PWN number were significantly reduced than untreated control. We suggest this screening method for PWN control agents.

Some Factors Affecting Bone Mineral Status of Premenopausal Women

  • Oh, Se-In;Bae, Hyeon-Ju
    • Proceedings of the Korean Journal of Food and Nutrition Conference
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    • 2003.07a
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    • pp.76-76
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    • 2003
  • This study was conducted to investigate dietary and other factors affecting bone mineral density (BMD) in Korean premenopausal women. Seventy-eight premenopausal women who visited health promotion center for health examinations volunteered to participate in this study and they were divided into two groups according to the bone status by T-score : normal or osteopenic group and osteoporotic group. The demographic and general characteristics, and dietary intake were surveyed using the questionnaire. BMDs of the lumbar spine and femoral neck of subjects were measured by dual energy X-ray absorptiometry. Serum samples were measured for Lipid concentration, and calcium, phosphorus, alkaline phosphatase as bone formation indicators. Urine was analysed for creatinine as bone resolution indicators. The results are as follows:The mean BMDs of the lumbar spine and femoral neck were 1.21 0.02g/cm$^2$ and 0.97 0.04g/cm$^2$, respectively and the BMD levels of osteoporotic group were significantly lower than that of normal or osteopenic group (p<0.001, respectively). Height in osteoporotic group was significantly lower than that of normal or osteopenic group (p<0.01), and bodyweight did not show any significant difference but had a lower tendency. Mean daily intake of energy was 1720 52ka1. When nutrient intake was compared with recommended dietary allowances (RDA) of subjects, calcium, Fe, vitamin A and riboflavin intakes showed means lower than RDA. The nutrient intake did not show any significant difference between normal or osteopenic group and osteoporotic group except intakes of protein fat and niacin. Serum and urine levels did not show any significant differences between normal or osteopenic group and osteoporotic group and all were within normal range, however, serum alkaline phosphatase level of osteoporotic group was significantly higher than that of normal or osteopenic group (p<0.001). Height showed positive correlations with lumbar spine bone mineral density (LBMD, r=0.332, p<0.01), no correlation was found with femoral neck bone mineral density (NBMD). Age, age at menarche, bodyweight, body mass index (BMI) and obesity showed no correlation with BMD. The BMD of the lumbar spine was significantly and positively related to the intake of niacin and vitamin C (r=0.236, p<0.05; r=0.274, p<0.05). Serum levels of calcium and phosphorus showed a negative correlation with LBMD (r=-0.698, p=0.0001; r=-0.503, p=0.0001, respectively). The results suggested that the BMDs of the lumbar spine was positively related to the intake of niacin and vitamin C in premenopausal women. Therefore, this study confirmed that one of the most effective way to minimize bone loss would be higher intake of niacin and vitamin C rich foods and habitual physical activity may have a beneficial effect on BMD in premenopausal period.

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A comparative study of field measurements of the pressure wave with analytical aerodynamic model for the high speed train in tunnels (고속철도 터널내 압력파 측정과 공기압 해석모델에 대한 기초연구)

  • Kim, Hyo-Gyu;Choi, Pan-Gyu;Hong, Yoo-Jung;Yoo, Ji-Oh
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.17 no.3
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    • pp.319-332
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    • 2015
  • The pressure wave formed by the piston effects of the train proceeds within the tunnel when a train enters the tunnel with a high speed. Depending on the condition of tunnel exit, the compression waves reflect at a open end, change to the expansion waves, transfer to tunnel entrance back. Due to interference in the pressure waves and running train, passengers experience severe pressure fluctuations. And these pressure waves result in energy loss, noise, vibration, as well as in the passengers' ears. In this study, we performed comparison between numerical analysis and field experiments about the characteristics of the pressure waves transport in tunnel that appears when the train enter a tunnel and the variation of pressure penetrating into the train staterooms according to blockage ratio of train. In addition, a comparative study was carried out with the ThermoTun program to examine the applicability of the compressible 1-D model(based on the Method of Characteristics). Furthermore examination for the adequacy of the governing equations analysis based on compressible 1-D numerical model by Baron was examined.

Prevention Methods of Cyber-crimes using the Private Security (민간경비를 활용한 사이버범죄 예방 방안)

  • Kim, Sang-Woon;Jo, Hyun-Bin
    • The Journal of the Korea Contents Association
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    • v.13 no.3
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    • pp.141-151
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    • 2013
  • With the spread of Personal Computers(PC) in the 1980's, many people started to deal businesses with PC. From late 1990's, the Internet age with PC have started and many people have showed keen interest in cyber-space and now they are utilizing it. Since 2000's the use of cyber-space have skyrocketed and it caused significant changes to humans' life. There was a huge prosperity to us but the new kind of crime, cyber-crime, was raised. Unlike past physical type of crimes, those cyber-crimes take place in the cyber-space and they have special features of non-facing, anonymity, specialty, technologic, repetition, continuation. Those cyber-crimes are continually growing since 2003 and in 2010 it almost doubled compared to 2003. General cyber-crimes like phishing-scam pornography circulation was most of them and notably perpetrators of them are younger generation. Recently cyber-crimes are showing the trend of advancing more and more and cyber-bullying, fraud like phishing scam are on the rise. The police are responding by making 'Cyber Terror Response Center', but it does not work effectively with the problems of breakup of prevention and investigation unit, procedure of investigation and the system itself. So, I suggest practical use of private security to remedy our police's weakness and to prevent cyber-crimes. Preventing solutions of cyber-crime with private security are physical defense of large-scale servers and vital computers, building of Back-up system to prevent vital data loss, and building of cyber-crime preventing system combining software and hardware.

Clinical Study of Empyema Thoracis (농흉에 대한 임상적 고찰)

  • Kim, Tae-Nyeun;Lee, Young-Hyun;Chung, Jae-Chun;Kim, Chong-Suhl
    • Journal of Yeungnam Medical Science
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    • v.3 no.1
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    • pp.87-94
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    • 1986
  • Empyema thoracis following pneumonia, intra-abdominal pathology, trauma, and surgical procedure continues to be a source of major morbidity and mortality. Thirty seven adult and eleven pediatric patients with empyema thoracis were treated at the University of Yeungnam Medical Center from May 1983 to November 1986. Age distribution ranged from 6 months to 72 years and showed a double-peaked curve with the highest incidence between 36 and 65 years and below 15 years of age. There were male predominence in patients above 16 years of age. The most common predisposing factors was impaired consciousness due to either alcoholism or head injury. The causes of empyema were as follows: pneumonia 64.6%, lung abscess 6.4%, intraabdominal pathology 6.4%, and surgical procedure 6.4%. The cardinal symptoms were fever, cough, chest pain, dyspnea, sputum, weight loss, anorexia, and night sweat in orders. Culture of empyema fluid were positive in 50% of patients. The isolated organisms were Gram-negative bacilli 33.3%, staphylococcus aureus 25%, and streptococcus 25%. The patients received antibiotics in conjunction with various invasive procedures : chest tube drainage 77.1%, decortication 6.3%, and repeated thoracentesis 10.3%. There were 4 deaths, 1 child and 3 adults, with a overall mortality of 8.3%.

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Quality of Dry Noodle Prepared with Wheat Flour and Immature Rubus coreanus (Bogbunja) Powder Composites (미숙복분자 분말을 첨가한 건면의 품질특성)

  • Lee, Yong-Nim;Song, Guen-Seoup;Kim, Young-Soo
    • Applied Biological Chemistry
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    • v.43 no.4
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    • pp.271-276
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    • 2000
  • Dry noodles were prepared with wheat flour and immature Rubes coreanus (Bogbunja) powder, and the effects of added immature bogbunja powders on dough rheology and noodle quality were examined. Particle size distribution of immature bogbunja powder ranged from 0.04 to $500\;{\um}m$, which was different from that of wheat flour. The initial pasting temperature, peak and final viscosities as well as setback increased in amylograph with the increase of immature bogbunja powder. The water absorption and dough development time increased, but the dough stability decreased in farinograph with the increase of immature bogbunja powder. Decrease of L and b values and increase of a value were shown with the increase of immature bogbunja powder in wheat flour-immature bogbunja powder composite as well as dry noodles. The cooked weight and volume of noodles decreased, but the cooking loss increased with the addition of immature bogbunja powder. Most of texture parameters (hardness, cohesiveness, chewiness, gumminess and tension) of cooked noodles decreased with the addition of immature bogbunja powder. From the result of sensory evaluation, dry noodles containing 1 and 2% immature bogbunja powder were rated as higher quality dry noodles than the others.

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Hydraulic Experiments on the Measuring Equipments of Ronoff and Soil Loss (유출수 및 유실토량 측정장치에 관한 수리시험)

  • 유한열
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.10 no.1
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    • pp.1377-1387
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    • 1968
  • In order to measure runoff and soil losses produced in a small test plot during rainfall, it is usually insufficient to use a tank only, necessitating the combined use of a main tank and a subsidiary tank. Accordingly. exact measurement largely depends on how to connect those two measuring tanks. The main purpose of this thesis is to improve the connecting parts of two measuring tanks so as to assure exact measurement of runoff and soil losses. In this experiment, two types of main tank, i. e. A-type and B-type, were used. A-type is a square tank having a flume at its end. At the flume, ten apertures are provided by using metal columns so as to be able to catch one tenth of total muddy flow discharging at the end of the flume, One tenth of total flow is led to the subsidiary tank through a slot sampler fixed to an aperture. B-type differes in that its flume does not have apertures and slot sampler is fixed directly to the end of the flume, other features being the same as those of A-type. Discharge volumes were measured by using weighing tanks and compared. The effect of baffle screen provided in the flume was also observed in connection with exact measurements. In order to keep main tank and its flume in a horizontal position, bolts and nuts mechanism was used. Vertical and horizontal screens were provided in the main to prevent coarse sands coming into the flume. The conclusion derived through this experiment is as follows: (1) The discharge through slot sampler at each aperture is almost the same for A-type. However, it is slightly more than one tenth of total discharge volume. (2) In case that baffle screen is provided in the flume of A-type tank, the discharge volume of slot sampler is less than that of the same type without screen. (3) For B-type tank, slot sampler discharge increases as slot sampler nears toward the center of flume. (4) When baffle screen is provided in the flume of B-type, slot sampler discharge is less than that of the same type without screen, and this phenomenon is more apparent as compared with A-type. (5) In case that the slot width of slot sampler for B-type is one inch, slot sampler discharge exceeds one tenth of total discharge volume. (6) When the slot width for B-type is 15/16 inch and slot sampler is fixed 3/8 inch apart from either flume wall, slot sampler discharge is approximately equal to one tenth of total discharge volume.

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Consideration of Metaphors Appeared on Shaun Tan's 3D Short Animation, (숀 탠 (Shaun Tan)의 3D 애니메이션 에 나타난 은유적 표현에 대한 고찰)

  • Jang, Eun-Young
    • Cartoon and Animation Studies
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    • s.23
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    • pp.1-17
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    • 2011
  • The paper analyzed the metaphoric expressions appeared in whose cinematic quality has been subjectively recognized on the global stage by winning the Oscar for Best Animated Short Film. Many contents and visual effects of the film were expressed with metaphor. Story and sequence were analyzed through the language system-based 'Conceptual Metaphor Analysis Framework'. In addition, characters have been analyzed through the 'Visual Metaphor Analysis Framework'. The framework is to analyze visual dimensions which are derived when concepts are structuredin animation. This paper has attempted to investigate and reveal patterns how animation self-organizes or how animation self-realizes through linguistic objectives. That is, it is to reveal how animation communicates with the audience from the metaphoric perspective among many conventional ones. In an animated film, metaphor is a fundamental means to connect fragmented images, produce a holistic view and therefore induce creative communication with the audience. The essential motive of metaphor which is expressed in various styles in is modern people's feeling of loss and sense of missing something. Train, bottle top, food, lost-and-found center, in-between space and lost items have significance across the movie. According to an analysis, metaphor offers simplicity and freshness as an aesthetic function. In addition, the metaphor expresses lengthy contents and various meanings implicitly, delivering an economic function. With a creative function, metaphor is a tool to generate new meanings. In other words, an animated film is a medium to inspire and move the general public as a means of communication and thinking, not just an entertainment for young generations. After all, metaphoric expressions have been used to deliver diverse and deep meanings in animated films.

Spoilage Lactic Acid Bacteria in the Brewing Industry

  • Xu, Zhenbo;Luo, Yuting;Mao, Yuzhu;Peng, Ruixin;Chen, Jinxuan;Soteyome, Thanapop;Bai, Caiying;Chen, Ling;Liang, Yi;Su, Jianyu;Wang, Kan;Liu, Junyan;Kjellerup, Birthe V.
    • Journal of Microbiology and Biotechnology
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    • v.30 no.7
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    • pp.955-961
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    • 2020
  • Lactic acid bacteria (LAB) have caused many microbiological incidents in the brewing industry, resulting in severe economic loss. Meanwhile, traditional culturing method for detecting LAB are time-consuming for brewers. The present review introduces LAB as spoilage microbes in daily life, with focus on LAB in the brewing industry, targeting at the spoilage mechanism of LAB in brewing industry including the special metabolisms, the exist of the viable but nonculturable (VBNC) state and the hop resistance. At the same time, this review compares the traditional and novel rapid detection methods for these microorganisms which may provide innovative control and detection strategies for preventing alcoholic beverage spoilage, such as improvement of microbiological quality control using advanced culture media or different isothermal amplification methods.