• 제목/요약/키워드: existence of solutions

검색결과 944건 처리시간 0.024초

디지털시대에 있어서 주택임대차 존속기간에 대한 문제점과 개선방안 (Problems and Solutions for the Term of Existence of the Housing Lease in the Digital age)

  • 박종렬
    • 한국컴퓨터정보학회논문지
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    • 제20권4호
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    • pp.139-146
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    • 2015
  • 주택임대차보호법은 임차인의 주거생활과 법적지위를 개선하기 위하여 1981년 3월5일 법률 제3379호로 제정된 이후에 많은 문제점은 있었으나, 몇 차례의 개정을 걸쳐 종래의 미흡했던 부분을 개선하기도 했었다. 하지만 무주택영세민들의 지위강화를 실질적으로 보장해 주기 위해서는 아직도 많은 문제점을 해결해야할 필요성이 제기되고 있는 가운데, 국회는 2015년 2월14일 임차인 계약갱신청구권 도입을 두고 서민주거복지특별위원회를 가동하여 임시국회에서 현안을 논의하기로 했었으나 현재 찬반양론의 대립이 뚜렷하게 보이고 있는 실정이다. 그동안 임차인의 계약갱신청구권이 보장되지 않았었기 때문에 임대차의 최단존속기간이 경과하게 되면 임대인의 의사에 따라 계약갱신의 여부가 좌우됨으로서 무주택영세민들의 주거안정이 불안정할 수 있었다. 따라서 본 논문에서는 열악한 지위에 있는 임차인들의 주거생활 안정을 위해 우리의 존속기간규정을 분석하고, 각국의 존속기간과 비교 검토를 통하여 문제점에 대한 구체적인 입법방안을 제시하고자 한다.

직사각형 평판의 비선형 진동 (Non-linear Vibration of Rectangular Plates)

  • Chang, Seo-Il;Lee, Jang-Moo
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 1994년도 추계학술대회논문집; 한국종합전시장, 18 Nov. 1994
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    • pp.35-39
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    • 1994
  • One of the important characteristics of the response of nonlinear systems is the existence of subharmonic resonances. When some conditions in parameter space are satisfied. It is possible even in the presence of damping for a periodically excited nonlinear system to possess a response which is the combination of a contribution at the excitation frequency and a component at the system natural frequency. The system natural frequency being a submultiple of the excitation frequency implies that the resulting response is a subharmonic oscillation. In general, there also co-exists, for the system, a response at the excitation frequency, and initial conditions determine which of the steady-state responses is achieved in an experiment or a numerical simulation. In single-degree-of-freedom systems with harmonic excitation, depending on the type of the nonlinearity, e.g., cubic or quadratic the frequency of subharmonic response is respectively, one-third or one-half of that of the excitation frequency. Although subharmonic resonance is one of the principal characteristics of a nonlinear system the subharmonic responses of structures in the presence of internal resonances have been studied very rarely. In this work, we consider subharmonic responses in the two-mode approximation of the plate equations. It is assumed that the two modes are in one-to-one internal resonance. Constant and periodic steady-state solutions of the averaged equations are studied. Finally, the results of direct time integration of the original equations of motion are presented and compared with those obtained from the averaged equations.

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고로슬래그의 지오폴리머 축중합반응에 미치는 양생온도의 영향 (Effect of Curing Temperature on Geopolymeric Polycondensation of Blast Furnace Slag)

  • 전창섭;송태웅
    • 한국세라믹학회지
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    • 제48권6호
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    • pp.610-616
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    • 2011
  • The effect of curing temperature on basic geopolymeric reactivity and hardening behaviour of blast furnace slag were investigated using the mixture of pulverized slag and several alkaline solutions of relatively high concentration. For the pastes prepared at several different temperatures between 20$^{\circ}C$ and 90$^{\circ}C$, setting time and heat of reaction were examined while mineralogical and morphological examinations were performed for the hardened paste after curing period at same temperature. The geopolymeric reaction of slag was revealed to be accelerated strongly according to the curing temperature regardless of the sort and concentration of the alkaline solution. The increase of concentration of the alkaline solution within 9M and the existence of silicic ion in the solution also promoted the reaction severely. The mineral component and their ratio of the hardened paste were revealed to be influenced by the chemical species and silicic ion contained in alkaline solution rather than by the curing temperature. The higher temperature and longer period of curing stage were effective for the sustained formation of geopolymer and succeed improvement of density and uniformity of morphology of the final hardened body.

DYNAMICS OF GUN VIOLENCE BY LEGAL AND ILLEGAL FIREARMS: A FRACTIONAL DERIVATIVE APPROACH

  • Chandrali, Baishya;P., Veeresha
    • 호남수학학술지
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    • 제44권4호
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    • pp.572-593
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    • 2022
  • Crime committed by civilians and criminals using legal and illegal firearms and conversion of legal firearms into illegal ones has become a common practice around the world. As a result, policies to control civilian gun ownership have been debated in several countries. The issue arose because the linkages between firearm-related mortality, weapon accessibility, and violent crime data can imply diverse options for addressing criminality. In this paper, we have projected a mathematical model in terms of the Caputo fractional derivative to address the issues viz. input of legal guns, crime committed by legal and illegal guns, and strict government policies to monitor the license of legal guns, strict action against violent crime. The boundedness, existence and uniqueness of solutions and the stability of points of equilibrium are examined. It is observed that violent crime increases with the increase of crime committed by illegal guns, crime committed by legal guns and, decreases with the increase of legal guns, the deterrent effect of civilian gun ownership, and action of law against crime. Further, legal guns increase with the increase of the limitation of trade of illegal guns and decrease with the increase of conversion of legal guns into illegal guns and increase of the growth rate of illegal guns. Again, as crime is committed by legal guns also, the policy of illegal gun control does not assure a crime-free society. Weak gun control can lead to a society with less crime. Theoretical aspects are numerically verified in the present work.

Effects of Sodium Fluoride on the Water Transport in Leaves of Barley and Rice under Salt Stress in the Light

  • Hwang, Hong-Jin;Oh, Kwang-Hoon;Park, Phun-Bum;Lee, Choon-Hwan
    • Journal of Photoscience
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    • 제11권1호
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    • pp.25-28
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    • 2004
  • The kinetics of the loss of leaf fresh weight during incubation of barley and rice leaves in 9% or 15% NaCl solutions were biphasic, indicating the existence of a controlling mechanism for water transport. The first rapid phases reached their plateaus within 1 and 2 h in the case of rice and barley leaves, respectively. When barley leaves were fed with sodium fluoride, an inhibitor of phosphatase inhibitor, through their epicotyls for 3 h in darkness, prior to the treatment of NaCl, the biphasic pattern shown during NaCl treatment was disappeared resulting in linear decreases in the relative fresh weights. The results suggest that NaF accelerates salt-induced water efflux from plant cells, possibly by inhibiting the protection mechanism that may act in NaF-untreated leaves. The linear water loss can be explained in terms of phosphorylation of aquaporin by blocking its dephosphorylation in the presence of the phosphatase inhibitor to keep aquaporin in a phosphorylated form. However, the effect of NaF shown in barley leaves were not observed in rice. These results suggest that the regulation of water transport depends on plant species, and the mechanism for the controlling water transport in rice is different from that of barley.

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The effect of phosphate corrosion inhibitor on steel in synthetic concrete solutions

  • Sail, L.;Ghomari, F.;Khelidj, A.;Bezzar, A.;Benali, O.
    • Advances in materials Research
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    • 제2권3호
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    • pp.155-172
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    • 2013
  • The study of the corrosion inhibition of armatures made of steel conceived for reinforced concrete by sodium phosphate is the aim object of our experimental tests. Gravimetric and electrochemical measurements were carried in three different Mediums contaminated by chlorides (3% NaCl) with addition of increasing concentrations of sodium phosphate. Inhibitory efficiency reached 80% at an optimal concentration of $7,5{\times}10^{-3}M$, the results obtained using the gravimetric measurements are in good agreement with those obtained by electrochemical methods. However, the monitoring of the pH evolution after 24h shows in the three studied environments, that the pH decreases slightly at 24 hours from the initial pH at $t_0$, due to the presence of corrosion products which change the state of the final solution. Also, scanning electron microscopy revealed the existence of layers of apatite on the metal surface previously treated with the sodium phosphate which confirms the formation of a protective film around the surface of the metal.

Effects of Foreign Direct Investment and Quality of Informal Institution on the Size of the Shadow Economy: Application to Vietnam

  • NGOC, Bui Hoang
    • The Journal of Asian Finance, Economics and Business
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    • 제7권5호
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    • pp.73-80
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    • 2020
  • Tax is the main revenue of Government, so fighting tax evasion and sustainable growth have been the primary macroeconomic goals being pursued by every developing country, Vietnam included. The existence and development of the shadow economic sector are synonymous with the national budget losing out. In Vietnam, foreign direct investment projects do not promote economic growth and is also a sector that gives way to tax evasion.The purpose of this study is to investigate the impact of foreign direct investment, the quality of the informal institution on the size of the shadow economy in Vietnam, during the period 1991-2015. By applying the Autoregressive Distributed Lag approach and Toda and Yamamoto test, we found evidence to conclude that the quality of the informal institution harms the size of the shadow economy. The results of the causality test show that there is a unidirectional causality running from the shadow economy and the quality of the informal institution to foreign direct investment attraction in Vietnam. Political solutions need to be implemented carefully to counter the harmful effects of the shadow economy. Policymakers should adopt several economic policies to improve the 'human capital' and drive the shadow economy into the formal economy.

비이온계 계면활성제 수용액이 PET직물의 습윤특성에 미치는 영향 제1보 : Span 20과 Tween 20의 혼합계와 희석계 (Effect of Nonionic Surfactant Solutions on Wetting and Absorbancy of PET Fabric 1. Mixtures and Dilutions of Span 20 and Tween 20)

  • 김천희
    • 한국의류학회지
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    • 제27권9_10호
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    • pp.1153-1159
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    • 2003
  • The effects of changing aqueous solution properties by nonionic surfactants on wetting behavior and water retention properies of hydrophobic PET (polyethylene terephthalate) fabric were reported. The aqueous solution properties were diversified by mixing and diluting two nonionic surfactants, i.e., sorbitan monolaurate (Span 20) and polyoxyethylene(20) sorbitan monolaurate (Tween 20). The surface wetting properties ($cos{\theta}$) of PET fabric were greatly improved by adding $10^{-1}g/dl$ Tween 20 and further improved by mixing Span 20 to the system. The water retention properties (W) of PET fabric were also greatly increased by addition of $10^{-1}g/dl$ Tween 20. In diluted surfactant systems, the $cos{\theta}'s$ were increased with decreasing surface tension of aqueous liquids. The ratios of aqueous liquid retained in the pore structure to liquid retention capacity (W/H) were also increased with decreasing surface tension, however, W/H values were dramatically increased right after critical micelle concentration (cmc). The existence of micelles was important for the retention of aqueous liquids in the fabric. The critical surface tension of PET fabric used was found to be 28.7dyne/cm.

존재론적 장소개념에 의한 전통공간 해석에 관한 연구 (The Interpretation of Traditional Space Based on the Theory of Ontological Space)

  • 이옥재;김문덕
    • 한국실내디자인학회논문집
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    • 제23권4호
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    • pp.94-102
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    • 2014
  • Nowadays when the social and cultural paradigm is changing, the incomplete space is becoming a matter of controversy. In order to figure out the solutions to it, are being held a variety of spatial discourses for spatial essence and meaning to be cleared. Accordingly, this study has tried to seek for any probability to interpret the ontology shown at any traditional space on the ground of Heidegger's Ontological Thinking Structure which has a considerable impact on Modern Space, whose conclusions are the followings. First, Heidegger's ontological space theory, which provided a foundation of Placeness concept, includes not only the character of interdisciplinary learning among philosophy, arts and any related studies but also that of mutual oriental and occidental cultures. Second, between the thoughts of Heidegger and Lao-tzu are considerable similarities from the methodical viewpoint that materializes the meaning of existence as an essence. Third, for a convenient interpretation, the ontological spatial concept of Lao-tzu's philosophy shown at traditional spaces have been categorized into Typology-Incident, Morphology-situation and Topology-meaning generation with Schultz's Existential Spatial Concept based on Heidegger's Ontology as a medium. In particular, the meaning generation which materializes the placeness has the trait of being clarified as the product of interactions between incidents and situations.

서울일대 암반을 대상으로 한 Geotechnical Information System(GTIS)의 개발 및 활용(1) (A Development and Utilization of Geotechnical Information System(GTIS) of the Rock Mass in A Seoul Metropolitan Area(1))

  • 김정엽;전효택;박형동
    • 터널과지하공간
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    • 제5권4호
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    • pp.336-346
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    • 1995
  • Geotechnical Information System (GTIS) for efficient management of three dimensional borehole data has been developed. Some problems were raised during the input process of borehole data, and alternative solutions were sought. According to the previous geotechnical reports, there is no unified weathering classification scheme. A criterion, 100 times/30cm from SPT, was turned out inappropriate to the discrimination of weathered rock from weathered soil. It has also been suggested that weathered soil, weathered rock, soft rock, and hard rock should be defined as CW, HW, MW, and SW~fresh condition. For better comparison of RQD, the use of NX size coring is recommended for the whole area although BX size coring has been used in excavated area. The limit of drilling depth up to 1 m from the top of surface of hard rock should be extended to avoid possible wrong interpretation of rock head due to the existence of corestone. The input data were analysed by geostatistical methods. It is found that the range in semivariogram is about 300m, and the variance of gneiss is greater than that of granite. It is because the granite data analysed came from almost single uniform rock mass(i.e.Seoul granite), but gneiss data came from the rock mass(i.e. Gyeonggi gneiss complex experienced several metamorphic metamorphic processes.

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