• Title/Summary/Keyword: Current limiting

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Effects of Maternal Nutrition during Pregnancy on the Body Weight, Muscle Fiber Number, Carcass Traits, and Pork Quality Traits of Offspring

  • Choe, J.H.;Choi, Y.M.;Ryu, Y.C.;Lee, S.H.;Kim, B.C.
    • Asian-Australasian Journal of Animal Sciences
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    • v.23 no.7
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    • pp.965-971
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    • 2010
  • The purpose of the current study was to examine the influence of different maternal nutrition treatments during pregnancy on body weight, muscle fiber number, carcass traits, and pork quality traits of offspring. A total of 18 crossbred sows (Landrace${\times}$Yorkshire${\times}$Duroc) were randomly assigned to one of three nutritional treatment groups; control, high energy, and high protein. The control group was fed a standard diet, the high energy group was fed a diet that contained 30% increased metabolizable energy, and the high protein group was fed a diet that contained 30% increased limiting amino acids compared to the control. The sows in each group were fed equal quantities of each diet (1.9 kg/d) for the entire gestational period. A total of 36 piglets from each sow were used to evaluate changes in body weight, muscle fiber number in the longissimus dorsi muscle at birth, carcass traits, and pork quality traits. Birth weight of offspring born to sows in the high energy diet group was significantly higher compared to the high protein diet group (p<0.05). However, body weight of offspring after birth was not significantly different between the groups. Muscle fiber number for the longissimus dorsi muscle at birth was not significantly different between the groups. In addition, there were no significant differences in carcass traits or pork quality traits between offspring born to sows in the control group and those born to sows that received high energy or high protein diets during pregnancy. Based on these results, it appears that maternal nutrition treatment during pregnancy, regardless of whether it is with high energy or high protein diets, does not have a significant effect on body weight, muscle fiber number at birth, carcass traits, or pork quality traits.

Effects of thinning intensity on nutrient concentration and enzyme activity in Larix kaempferi forest soils

  • Kim, Seongjun;Han, Seung Hyun;Li, Guanlin;Yoon, Tae Kyung;Lee, Sang-Tae;Kim, Choonsig;Son, Yowhan
    • Journal of Ecology and Environment
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    • v.40 no.1
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    • pp.5-11
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    • 2016
  • Background: As the decomposition of lignocellulosic compounds is a rate-limiting stage in the nutrient mineralization from organic matters, elucidation of the changes in soil enzyme activity can provide insight into the nutrient dynamics and ecosystem functioning. The current study aimed to assess the effect of thinning intensities on soil conditions. Un-thinned control, 20 % thinning, and 30 % thinning treatments were applied to a Larix kaempferi forest, and total carbon and nitrogen, total carbon to total nitrogen ratio, extractable nutrients (inorganic nitrogen, phosphorus, calcium, magnesium, potassium), and enzyme activities (acid phosphatase, ${\beta}$-glucosidase, ${\beta}$-xylosidase, ${\beta}$-glucosaminidase) were investigated. Results: Total carbon and nitrogen concentrations were significantly increased in the 30 % thinning treatment, whereas both the 20 and 30 % thinning treatments did not change total carbon to total nitrogen ratio. Inorganic nitrogen and extractable calcium and magnesium concentrations were significantly increased in the 20 % thinning treatment; however, no significant changes were found for extractable phosphorus and potassium concentrations either in the 20 or the 30 % thinning treatment. However, the applied thinning intensities had no significant influences on acid phosphatase, ${\beta}$-glucosidase, ${\beta}$-xylosidase, and ${\beta}$-glucosaminidase activities. Conclusions: These results indicated that thinning can elevate soil organic matter quantity and nutrient availability, and different thinning intensities may affect extractable soil nutrients inconsistently. The results also demonstrated that such inconsistent patterns in extractable nutrient concentrations after thinning might not be fully explained by the shifts in the enzyme-mediated nutrient mineralization.

Seasonal Variations in Nutrients and Chlorophyll-a Concentrations in the Northern East China Sea

  • Kim, Dong-Seon;Shim, Jeong-Hee;Yoo, Sin-Jae
    • Ocean Science Journal
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    • v.41 no.3
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    • pp.125-137
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    • 2006
  • Nutrients, chlorophyll-a, particulate organic carbon (POC), and environmental conditions were extensively investigated in the northern East China Sea (ECS) near Cheju Island during three seasonal cruises from 2003 to 2005. In spring and autumn, relatively high concentrations of nitrate ($2.6{\sim}12.4\;{\mu}mol\;kg^{-1}$) and phosphate ($0.17{\sim}0.61\;{\mu}mol\;kg^{-1}$) were observed in the surface waters in the western part of the study area because of the large supply of nutrients from deep waters by vertical mixing. The surface concentrations of nitrate and phosphate in summer were much lower than those in spring and autumn, which is ascribed to a reduced nutrient supply from the deep waters in summer because of surface layer stratification. While previous studies indicate that upwellings of the Kuroshio Current and the Changjiang (Yangtze River) are main sources of nutrients in the ECS, these two inputs seem not to have contributed significantly to the build-up of nutrients in the northern ECS during the time of this study. The lower nitrate:phosphate (N:P) ratio in the surface waters and the positive correlation between the surface N:P ratio and nitrate concentration indicate that nitrate acts as a main nutrient limiting phytoplankton growth in the northern ECS, contrary to previous reports of phosphate-limited phytoplankton growth in the ECS. This difference arises because most surface water nutrients are supplied by vertical mixing from deep waters with low N:P ratios and are not directly influenced by the Changjiang, which has a high N:P ratio. Surface chlorophyll-a levels showed large seasonal variation, with high concentrations ($0.38{\sim}4.14\;mg\;m^{-3}$) in spring and autumn and low concentrations ($0.22{\sim}1.05\;mg\;m^{-3}$) in summer. The surface distribution of chlorophyll-a coincided fairly well with that of nitrate in the northern ECS, implying that nitrate is an important nutrient controlling phytoplankton biomass. The POC:chlorophyll-a ratio was $4{\sim}6$ times higher in summer than in spring and autumn, presumably because of the high summer phytoplankton death rate caused by nutrient depletion in the surface waters.

Saussurea Lappa Radix-induced cytotoxicity via ROS generation in A549 lung cancer cells (A549세포에 대한 목향추출물의 ROS 매개 세포독성)

  • Lee, Young-Joon;Ku, Sae-Kwang;Kang, Su-Jin
    • Journal of Society of Preventive Korean Medicine
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    • v.17 no.2
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    • pp.169-178
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    • 2013
  • Objectives : Many cancers acquired resistance to chemotherapy, thus limiting its anticancer efficacy. It is known that Glutathione (GSH) is related to the development of drug resistance. The expression of GSH synthesizing glutamylcysteine ligase (GCL) was controlled by nuclear factor-E2-related factor(Nrf2). Previous studies showed that pharmacological depletion of GSH results in ROS increase, apoptotic response, and sensitization to oxidizing stimuli. In the current study, we examined Saussurea Lappa (SL) have the inhibitory effect on Nrf2 activity using human lung cancer A549 cells overexpressing Nrf2. Methods : Cell viability of A549 cells on SL treatment was determined by MTT assay. To detect the apeptosis in SL-treated A549 cells, sub-G1 population was measured by flow cytometry analysis (FACS). The level ROS was determined by FACS and fluorescence microscopy. To investigate whether SL have effect the suppression on Nrf2, we performed western blotting analysis. The GSH content was measured since GSH plays an important role in response to oxidative stress and was regulated by Nrf2. Results : A549 cells treated with an SL extract showed a substantial decrease in cell viability, along with a concomitant increase in apoptosis compared to untreated cells. Treatment of the SL extract led to increased Reactive oxygen species (ROS) production and a suppression of Nrf2. In addition, the antioxidant NAC attenuated SL-induced ROS generation, Nrf2 inhibition, and apoptosis. Taken together, these data show that the SL extract induced the production of ROS, and the inhibition of Nrf2, consequently resulting in A549 cell death. Conclusions : These results suggest that SL might be an effective agent to enhance anticancer drug sensitivity via Nrf2 inhibition.

Analysis of a Harmonics Neutralized 48-Pulse STATCOM with GTO Based Voltage Source Converters

  • Singh, Bhim;Saha, Radheshyam
    • Journal of Electrical Engineering and Technology
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    • v.3 no.3
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    • pp.391-400
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    • 2008
  • Multi-pulse topology of converters using elementary six-pulse GTO - VSC (gate turn off based voltage source converter) operated under fundamental frequency switching (FFS) control is widely adopted in high power rating static synchronous compensators (STATCOM). Practically, a 48-pulse ($6{\times}8$ pulse) configuration is used with the phase angle control algorithm employing proportional and integral (PI) control methodology. These kinds of controllers, for example the ${\pm}80MVAR$ compensator at Inuyama switching station, KEPCO, Japan, employs two stages of magnetics viz. intermediate transformers (as many as VSCs) and a main coupling transformer to minimize harmonics distortion in the line and to achieve a desired operational efficiency. The magnetic circuit needs altogether nine transformers of which eight are phase shifting transformers (PST) used in the intermediate stage, each rating equal to or more than one eighth of the compensator rating, and the other one is the main coupling transformer having a power rating equal to that of the compensator. In this paper, a two-level 48-pulse ${\pm}100MVAR$ STATCOM is proposed where eight, six-pulse GTO-VSC are employed and magnetics is simplified to single-stage using four transformers of which three are PSTs and the other is a normal transformer. Thus, it reduces the magnetics to half of the value needed in the commercially available compensator. By adopting the simple PI-controllers, the model is simulated in a MATLAB environment by SimPowerSystems toolbox for voltage regulation in the transmission system. The simulation results show that the THD levels in line voltage and current are well below the limiting values specified in the IEEE Std 519-1992 for harmonic control in electrical power systems. The controller performance is observed reasonably well during capacitive and inductive modes of operation.

Trends in adherence to dietary recommendations among Korean type 2 diabetes mellitus patients

  • Park, Kyong
    • Nutrition Research and Practice
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    • v.9 no.6
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    • pp.658-666
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    • 2015
  • BACKGROUND/OBJECTIVES: The current study examined trends in adherence to dietary recommendations and compared the levels of adherence between diagnosed and undiagnosed subjects with type 2 diabetes mellitus (T2DM) in Korea over the past 14 years. SUBJECTS/METHODS: Data were collected from the 1998-2012 Korea National Health and Nutrition Examination Surveys (KNHANES). Diagnosed diabetes was defined as giving a positive response to questions about awareness of the disease, a physician's diagnosis of diabetes, or medical treatment for diabetes, whereas undiagnosed diabetes was defined as having a fasting glucose level ${\geq}126mg/dl$. Assessment of adherence level was based on 6 components of dietary guidelines, considering meal patterns and intake levels of calories, carbohydrates, vegetable/seaweed, sodium, and alcohol. The participants received 1 point if they met the criteria for each of the 6 components, and the total possible score ranged from 0 to 6 points. Multivariate generalized linear regression was performed, taking into account the complex survey design. RESULTS: Among all diabetic patients aged 30 years or older, the proportion of diagnosed diabetes increased dramatically, from 40.9% in 1998 to 75.9% in 2012 (P for trend < 0.001). The overall adherence levels to dietary recommendations were low and did not significantly differ between diagnosed and undiagnosed subjects with T2DM for all survey years. Several improvements were observed, including increased adherence to maintaining sufficient vegetable/seaweed consumption (increased from 0.12 to 0.16 points) and limiting sodium intake (increased from 0.12-0.13 points to 0.19-0.24 points; P for trend < 0.001), while adherence to maintaining moderate alcohol consumption decreased. CONCLUSIONS: Analysis of data collected by the KNHANES indicates that Korean T2DM patients have poor adherence to dietary recommendations and maintenance of a healthy lifestyle, regardless of disease awareness. This finding suggests that development of practical, evidence-based guidelines is necessary and that provision and expansion of educational programs for T2DM patients is critical after diagnosis.

Development and Assessment of Multi-sensory Effector System to Improve the Realistic of Virtual Underwater Simulation (가상 해저 시뮬레이션의 현실감 향상을 위한 다감각 효과 재현 시스템 개발 및 평가)

  • Kim, Cheol-Min;Youn, Jae-Hong;Kang, Im-Chul;Kim, Byung-Ki
    • Journal of Korea Multimedia Society
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    • v.17 no.1
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    • pp.104-112
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    • 2014
  • With recent development of virtual reality technology, coupled with the growth of the marine industry, virtual underwater simulation systems are under development in various studies, for educational purposes and to simulate virtual reality experiences. Current literature indicates many underwater simulation systems to date have focused on the quality of visual stimulus delivered through three-dimensional graphics user interface, limiting the reality of the experience. In order to improve the quality of the reality delivered by such virtual simulations, it is crucial to develop multi-sensory technology rather than focus on the conventional audio-visual interaction, which limits experiencer from the sense of underwater immersion and existence within the simulation. This work proposes the immersive multi-sensory effector system, delivering the users with a more realistic underwater experience. The sense of reality perceived was evaluated, as the main factor of the virtual reality system.

Safety and Effectiveness of Food Allergen Immunotherapy (Oral): A Systematic Literature Review and Meta-analysis

  • Mo, Jin-A;Joo, Yea-Il
    • International Journal of Contents
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    • v.14 no.3
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    • pp.39-45
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    • 2018
  • Purpose: Food Allergen Immunotherapy (Oral) is a form of immunotherapy administered to patients who are allergic to foods such as egg, milk, and peanut. The food allergen is orally administered to the patient in an escalating dose for desensitization or tolerance development. The safety and effectiveness of the therapy were assessed using a systematic literature review and meta-analysis. Methods: For a literature search, 8 national databases and a number of international databases including Ovid-MEDLINE, Ovid-EMBASE, and Cochrane Library were used; and 13 articles (all from international databases) were selected. The target of Food Allergen Immunotherapy (Oral) included patients with food allergy, and the intervention was food allergen immunotherapy without limiting the food type. The safety and effectiveness of Food Allergen Immunotherapy (Oral) were assessed by reviewing all the articles reporting on the therapy. The control group received standard therapies including aversion therapy, no treatment, anti-histamine treatment, and placebo. Safety was assessed through the incidence of complication and emergency medication. Effectiveness was assessed based on therapy success rate, symptomatic improvement, and quality of life. Results: Although Food Allergen Immunotherapy (Oral) was shown to have successful desensitization in patients with food allergy, the safety of the technique has not yet reached an acceptable level; the possible reason is due to the high rate of complication and frequency of emergency medication. Also, each study employed varying protocols while relying on a small number of participants and a short monitoring period. Conclusion: The results of assessment suggest that the level of evidence from current literature review is low and further research is necessitated for the verification of the safety and effectiveness of the therapy (Grade of Recommendation: A; Level of Technology: II-b).

A Study of Over Voltage Ground Relay Operation Status at Opening of No-load Charged Cable (무부하 충전케이블 개방시 잔류전압에의한 과전압계전기 동작현상 연구)

  • Kim, Yeong-Han;Choi, Jong-Hyuck;Yoon, Ki-Seob
    • Proceedings of the KIEE Conference
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    • 2000.07a
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    • pp.185-187
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    • 2000
  • Fault current is flowed into 154/23kV M. Tr when line-to-ground fault occurs in power system. NGR(Neutral Grounded Reactor) is set up in order to prevent M.Tr fault by limiting magnitude of fault currents. Here, disconnection of NGR causes voltage increase by L-C resonance and line-to-ground fault in an unearthed system results in voltage increase at healthy phases. So Over Voltage Ground Relay(OVGR) is used for tripping M.Tr. Also, buses at second phases of M.Trs are all connected with section circuit breakers closed for the purpose of parallel operation and load shedding. In case of speciality buses are comprised of power cable in part for GIS connection. When no-load charged cable or bus is open by a section CB, unbalanced voltage charged on the bus is induced. Also discrepant opening time for circuit breakers on different phases gives rise to unbalanced zero sequence voltage. It was observed that this zero sequence voltage detected in the 22.9kV P.T (Potential Transformer for bus) mal-operated 59GT and tripped M.Tr. The zero sequence voltage of which vanishing time is longer than relay operating time came out by EMTDC simulation. Also, it was shown that the voltage waves of actual test are similar to those of simulation. On the basis of above results, R-C circuit complement on the relay without any effect on a power system made operating time of the relay longer than vanishing time of distorted waves. Consequently, operating time of the relay was delayed and magnitude of distorted waves was decreased by increasing time constant of the relay.

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A Case Study on the Status and Problems of Regulations of Land Use in Gyeonggi-do (경기도 토지이용규제 현황과 문제점 고찰)

  • Kim, Young-Hoon;Kwon, Gyoung-Nam
    • KIEAE Journal
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    • v.16 no.6
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    • pp.57-67
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    • 2016
  • Purpose: Laws and regulations of land use are enormous, and the appliance of regulations is overlapped redundantly. Therefore, there are many problems such as time consuming in the process, limiting individual property rights, and interrupting enterprises' economic activities. This study will discuss problems of redundant regulations of land use and its improvement by figuring out current regulations of land use in Gyeonggi-do, one of provinces which applies the most various regulations of land use. Method: This study reviews laws on national land-use planning system and characteristics of land-use regulation in Korea. The extent of the review is limited to "framework act on the regulation of land use" with categories of national land, urban planing, architecture, etc. Through case studies in Gyeonggi-do, the status and problems of redundant regulations of land use are defined. For example, it is overlapped in "Seoul Metropolitan Area Readjustment Planning Act", Development Restriction Zone, Paldang Special District, and so on. It is mainly referred to 2015 Gyeonggi-do land-use restriction map. Result: First, Gyeonggi-do confronts many problems related to the development restrictions and the financial increasement for environmental management by redundant regulations. The development restrictions include supplying additional land for industrial use, relocating colleges, and height limitation relating to military facilities. Second, in order to organize redundant regulations, it is required to combine similar regulations and adjust through communication system among other departments. Third, regulations should consider unique local condition of each district. Lastly, efficient application of regulations is necessary so as to maximize the function of land, protect individual property rights, and stimulate local development.