• Title/Summary/Keyword: Marx

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Characteristics of Lightning Overvoltages Coming in Low-Voltage Power Distribution Systems

  • Lee, Bok-Hee;Lee, Dong-Moon;Lee, Su-Bong;Jeong, Dong-Cheol;Lee, Jae-Bok;Myung, Sung-Ho
    • KIEE International Transactions on Electrophysics and Applications
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    • v.3C no.3
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    • pp.91-98
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    • 2003
  • The importance of improving the quality of electric power is being strongly raised, owing to an increasing use of sensitive and small-sized electronic devices and systems. The transient over-voltages on low-voltage power distribution systems are induced by direct or indirect lightning return strokes. These can cause damage and/or malfunction of the utility systems for home automation, office automation, factory automation, medical automation, etc. The behaviors of lightning overvoltages transferred through the transformer to the low-voltage distribution systems using a Marx generator were experimentally investigated. Furthermore, the coupling mechanisms of lightning overvoltages transferred to the low-voltage systems were clearly illustrated through a theoretical simulation using a Pspice program. The overvoltages in low-voltage ac power systems are rarely limited by the application of the surge arrester to the primary side of the distribution transformer. A superior surge protection scheme is to install surge protection devices at the service entrance switchboard and/or at the load devices in TN power systems.

Lightning Surges Transferred to Low-voltage AC Power Lines through Distribution Transformers (배전용 변압기를 통하여 저압 전원선으로 전파되는 뇌서지)

  • 이복희;이동문;이수봉
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.17 no.4
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    • pp.94-99
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    • 2003
  • A strong need to improve the quality of electric power is increased because of increasing use of the sensitive and small-sized electronic devices. The transient overvoltages on low-voltage AC power distribution systems are induced by direct or indirect lightning return strokes, and they can cause damage and/or malfunction of the utility systems for home automation, office automation and factory automation as well as medical equipment. The behaviors of lightning overvoltages transferred through the transformer to the low voltage AC power distribution systems were experimentally investigated using a Marx generator. The surge voltages in low-voltage ac power systems are rarely limited by the application of the surge arrester to the primary side of distribution transformer and a custom service ground.

Mechanical robustness of AREVA NP's GAIA fuel design under seismic and LOCA excitations

  • Painter, Brian;Matthews, Brett;Louf, Pierre-Henri;Lebail, Herve;Marx, Veit
    • Nuclear Engineering and Technology
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    • v.50 no.2
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    • pp.292-296
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    • 2018
  • Recent events in the nuclear industry have resulted in a movement towards increased seismic and LOCA excitations and requirements that challenge current fuel designs. AREVA NP's GAIA fuel design introduces unique and robust characteristics to resist the effects of seismic and LOCA excitations. For demanding seismic and LOCA scenarios, fuel assembly spacer grids can undergo plastic deformations. These plastic deformations must not prohibit the complete insertion of the control rod assemblies and the cooling of the fuel rods after the accident. The specific structure of the GAIA spacer grid produces a unique and stable compressive deformation mode which maintains the regular array of the fuel rods and guide tubes. The stability of the spacer grid allows it to absorb a significant amount of energy without a loss of load-carrying capacity. The GAIA-specific grid behavior is in contrast to the typical spacer grid, which is characterized by a buckling instability. The increased mechanical robustness of the GAIA spacer grid is advantageous in meeting the increased seismic and LOCA loadings and the associated safety requirements. The unique GAIA spacer grid behavior will be incorporated into AREVA NP's licensed methodologies to take full benefit of the increased mechanical robustness.

A Study on The Business Cycle Theory of Tugan-Baranowsky (투간 바라노프스키의 경기 변동론에 대한 연구)

  • Ryu, Seung-min
    • 사회경제평론
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    • v.29 no.1
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    • pp.71-98
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    • 2016
  • This study reveals the followings in the Tugan's business cycle thoery. First, Tugan tried to construct a business cycle theory based on his market theory. But Tugan' theory is lack of logical consistency. Second, Tugan's critics as well as defenders did not understand his theoretical error. Underconsumption theorists did not evaluate Tugan's periodical crisis theory while only criticizing Tugan's crisis theory neglected a consumption. Bauer developed Tugan's periodical crisis by using the reproduction scheme including a hoarded money. Hilferding only constructed a theory of crisis properly criticizing Tugan's crisis theory on the basis of Marx's concept of crisis.

Capital Theory and Capital Measurement Problem (자본이론과 자본측정문제)

  • 박일근
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.8 no.11
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    • pp.57-68
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    • 1985
  • Theories of capital have historically been amongst the most fertile sources of economic controversy. Many aspects of the modern debate, if not the techniques employed in its exposition, would have been as familiar to Marx, Ricardo, Bohm-Bawerk or Wicksell as to any present-day Cambridge economist. That conotroversies should arise in the course of theorizing cm the concept of capital and the function of profit is not surprising: that these debates have been so vigorous and virluent cannot be divorced from the general ideological and specific implications associated with the theories. In the context of a textbook on the theories of economic growth, the central question associated with capital that must he faced is whether the existence in the real world of heterogeneous capital goods inevitably invalidate; the conclusions of simple theories of "parables" which incorporate no more than a conception of a single, malleable, capital good. All the Cambridge writers have, to a greater or lesser extent, been concerned to deny that any unit can be found in which heterogeneous capital goods can be aggregated so as to simultaneously satisfy the pair of neoclassical requirements described above. Some of them have been more prepared than others to countenance such a possibility or, for practical purposes, to use some concept of aggregate capital in their models, but they are all deeply suspicious of attempts to use aggregate production function, incorporating aggregate "capital", so as to explain the flow of output, relative factor prices and the distribution of income.tribution of income.

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Ramon Guillermo, Scholar-Activist of Indonesian and Philippine Society

  • Eliserio, UZ.
    • SUVANNABHUMI
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    • v.12 no.1
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    • pp.157-175
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    • 2020
  • This paper presents the work of Southeast Asian scholar Ramon Guillermo. Using sophisticated computer-aided methods, Guillermo approaches a range of topics in the wide fields of social sciences and the humanities. A creative writer as well as an activist, Guillermo grounds his studies in nationalism and Marxism. Particularly interested in Indonesian and Philippine society and culture, Guillermo engages with the writings of labor leaders Tan Malaka and Lope K. Santos, translations of Marx's Capital into Bahasa and Filipino, and studies as well the discursive and historical connections between the Communist Parties of both countries. The paper aims to introduce the innovations of Guillermo's studies, particularly in the fields of cultural studies and translation studies. The type of cultural studies Guillermo practices is empirical, taking inspiration from innovations done in the digital humanities. Guillermo is most opposed to trendy, fashion-seeking approaches that are not grounded on history. He reserves particular ire for "hip" postcolonialism, and instead praises studies that are founded on politics and materialism. In translation studies, Guillermo goes beyond the mere cataloguing of mistakes. For him, it is the mistakes and "perversities" of a translation that is interesting and illuminating. Guillermo himself is a translator, and the paper ends with a brief discussion of his production in this field.

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Primary versus revision total shoulder arthroplasty: comparing relative value and reimbursement trends

  • Carney, John Joseph;Gerlach, Erik;Plantz, Mark;Swiatek, Peter Raymond;Marx, Jeremy;Saltzman, Matthew;Marra, Guido
    • Clinics in Shoulder and Elbow
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    • v.25 no.1
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    • pp.42-48
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    • 2022
  • Background: Total shoulder arthroplasty (TSA) has been demonstrated to be an effective treatment for multiple shoulder pathologies. The purpose of our study was to compare the relative value units (RVUs) per minute of surgical time for primary and revision TSA. Methods: The American College of Surgeons National Surgical Quality Improvement Program database was queried to identify patients that underwent primary TSA, one-component revision TSA, and two-component revision TSA between January 1, 2015 and December 31, 2017 using current procedure terminology codes. RVUs were divided by mean operative time for each procedure to determine the amount of revenue generated per minute. Rates were compared between the groups using a one-way analysis of variance with post-hoc Tukey test. Statistical significance was set at p<0.05. Results: When dividing compensation by surgical time, we found that two-component revision generated more compensation per minute compared to primary TSA (0.284±0.114 vs. 0.239±0.278 RVU per minute or $10.25±$4.11 vs. $8.64±$10.05 per minute, respectively; p=0.001). Conclusions: The relative value of revision TSA procedures is weighted to account for the increased technical challenges and time associated with these procedures. This study confirms that reimbursement is higher for revision TSA compared to primary TSA.

Dispute on Freudian Legacy and a Paradigm Shift (프로이트 비판 논쟁과 패러다임의 변화)

  • Kwon, Teckyoung
    • Journal of English Language & Literature
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    • v.56 no.1
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    • pp.157-178
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    • 2010
  • A critique on Freud's remembering taken place in the 80's and 90s has a significant impact on a paradigm shift: from the discursive constructivism to the neo-empiricism. Along with Marx and Nietzsche, Freud was one of the main intellectual sources in formulating the Cultural Studies, known as the political corrections in the later period of Post-modern era. In the wake of feminism, there was a social happening, namely, a memory restoration, when a woman therapist helped a woman patient to restore the past and come up with her father as the cause of her trauma. Finally, 'the false memory syndrome' brought up a hot issue firing on the controversy about Freudian remembering. Freud as a clinical therapist began to be a sole target to be criticized. Strangely enough, however, Freud was continually utilized by such theorists as Julia Kristeva, Homi Bhabah, and Žižek, while having dissenters like Deleuze, Quattari, and Butler. Of those intellectual claims, this paper focuses on the debates by the dissenters not from the discursive theorists but from the clinical studies: Sulloway, Grunbaum, and Crews. My argument directs to the empirical side of Freud for the conclusion that the dispute on him was a seed of a paradigm shift towards the neo-empiricism, after one century's flourishing of constructivism.

FEATURES OF HISTOPATHOLOGIC AND RADIOGRAPHIC FINDINGS IN BISPHOSPHONATE-RELATED OSTEONECROSIS OF JAW-CLINICAL REVIEW (Bisphosphonate-related osteonecrosis of the jaw의 병리조직학적 소견 및 방사선학적 특징에 대한 임상적 고찰)

  • Ohe, Joo-Young;Kwon, Yong-Dae;Kim, Yeo-Gab;Lee, Baek-Soo;Yoon, Byoung-Wook;Choi, Byoung-Jun
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.34 no.5
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    • pp.550-554
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    • 2008
  • Bisphosphonates (BPs) are a class of agent used to treat patient with osteoporosis or malignant bone metastases. BPs can be categorized into 2 groups: nitrogen-containing and non-nitrogen containing. Nitrogen-containing BPs are considered to have more toxicity. Despite their clinical benefits, bisphosphonate-related osteonecrosis of jaw(BRONJ) is a significant complication to patients receveing these drugs. Since the first description of BRONJ in 2003 by Marx, the number of reports on BRONJ has been rapidly increasing. BRONJ is considered as an emerging problem in oral & maxillofacial surgery. Generally, osteonecrosis in the maxilla is rare, however BRONJ is found both in the maxilla and the mandible. This is an important feature of BRONJ compared to common infectious osteomyelitis of the jaw. Growing number of case reports, suggest that bisphosphonate therapy may cause exposed, necrotic bone. BRONJ has simillar features compared to IORN (infected osteoradionecrosis). BRONJ has meaningful features established through the interestigation on histopathologic and radiographic findings. These features have an impact on treatment plan and prognosis. This presentation contemplates on features of histopathologic and radiographic findings in bisphosphonate-related osteonecrosis of the jaw.

Potential Reduction and Energy Dispersion Due to Ionization Around the Submerged Ground Rod (수중에 잠긴 접지전극 주변에서의 이온화에 의한 전위저감 및 에너지방출)

  • Choi, Jong-Hyuk;Ahn, Sang-Duk;Yang, Soon-Man;Lee, Bok-Hee
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.23 no.1
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    • pp.92-99
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    • 2009
  • Deeply-driven ground rod in the rainy season may contact with rainwater and ground water. When surge voltages are applied to the submerged ground rods, the ionization around the ground rods are occurred. Ionization in soil and/or water is affected in dynamic performance of ground rod systems. This work aims at studying the transient performance of ground rod system under impulse voltage using scale model in an electrolytic tank. The potential reduction and energy dispersion caused by ionization were treasured and quantitatively analyzed using the Matlab Program. As a result, the peak voltage at the terminal of ground rod was varied with water resistivity and charging voltage of Marx generator. The potential at the terminal of the ground rod was approximately reduced to a half of the applied voltage just below breakdown voltage. Also the energy more than half of the applied energy was dispersed through the ground rod due to ionization just below breakdown voltage.