• Title/Summary/Keyword: existence of solutions

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Paramagnetic Zn(1-x)MnxO (0.00≤x≤0.06) Nanoparticles Prepared by The Coprecipitation Method

  • Harsono, Heru;Wardana, I Nyoman Gede;Sonief, Achmad As'ad;Darminto, Darminto
    • Transactions on Electrical and Electronic Materials
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    • v.18 no.1
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    • pp.46-50
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    • 2017
  • The Zn1-xMnxO ($0.00{\leq}x{\leq}0.06$) samples have been synthesized in the form of powder by the coprecipitation method at low temperature using $Zn(CH_3COO)_2$. $2H_2O$ and $Mn(CH_3COO)_2$. $4H_2O$ powders, as well as HCl and $NH_4OH$ solutions as starting materials. Characterization was conducted using XRD, TEM, XRF, FTIR and VSM. The result shows that the $Zn_{(1-x)}Mn_xO$ ($0.00{\leq}x{\leq}0.06$) nanoparticles have the wurtzite phase with a hexagonal structure and particle sizes ranging from 17.48 to 118.83 nm. In a qualitative analysis of XRF, the peaks that confirm the existence of the manganese element in Mn-doped ZnO samples were observed. Meanwhile, FTIR test result shows that there are peaks at around $500cm^{-1}$ and $400cm^{-1}$ in the FTIR spectra for Mn doped ZnO samples which clearly reveal the existence of the (Zn, Mn)-O strain mode. The (Zn, Mn)-O absorption peak positions have shifted to a lower wave number with increasing Mn doping content. The peak intensity is also lower if compared to that of the ZnO sample without doping. From the VSM test, it is shown that $Zn_{(1-x)}Mn_xO$ ($0.00{\leq}x{\leq}0.06$) nanoparticles are all paramagnetic having monotonically increased susceptibility as increasing Mn content.

Numerical simulation and investigation of jet impingement cooling heat transfer for the rotor blade

  • Peiravi, Amin;Bozorg, Mohsen Agha Seyyed Mirza;Mostofizadeh, Alireza
    • Advances in aircraft and spacecraft science
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    • v.7 no.6
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    • pp.537-551
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    • 2020
  • Investigation of leading edge impingement cooling for first stage rotor blades in an aero-engine turbine, its effect on rotor temperature and trailing edge wake loss have been undertaken in this study. The rotor is modeled with the nozzle for attaining a more accurate simulation. The rotor blade is hollowed in order for the coolant to move inside. Also, plenum with the 15 jet nozzles are placed in it. The plenum is fed by compressed fresh air at the rotor hub. Engine operational and real condition is exerted as boundary condition. Rotor is inspected in two states: in existence of cooling technique and non-cooling state. Three-dimensional compressible and steady solutions of RANS equations with SST K-ω turbulent model has been performed for this numerical simulation. The results show that leading edge is one of the most critical regions because of stagnation formation in those areas. Another high temperature region is rotor blade tip for existence of tip leakage in this area and jet impingement cooling can effectively cover these regions. The rotation impact of the jet velocity from hub to tip caused a tendency in coolant streamlines to move toward the rotor blade tip. In addition, by discharging used coolant air from the trailing edge and ejecting it to the turbines main flow by means of the slot in trailing edge, which could reduce the trailing edge wake loss and a total decrease in the blade cooling loss penalty.

Fluorescence Behavior of Benzo[f]Quinoline Doped In Lpd Silica Thin Films

  • Mabuchi, Toshiaki;Suzuki, Satoshi;Nakajima, Tsuyoshi;Ino, Juichi;Takemura, Kazuo;Shimizu, Etsuro
    • Journal of Photoscience
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    • v.5 no.3
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    • pp.105-109
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    • 1998
  • By using the liquid -phase-deposition (LPD) process, which has a potetnial of preparing organic inorganic composite materials, samples doped with benzo[f]quinoline (BfQ)into silica thia films wre prepared. We observed the fluorescene and fluorescene excitation spectra of the samples, as well as the fluorescence lifetimes and time-resoluved fluorescence spectra. The comparison of thefluorescence spectra in pH-controlled buffer solutions yields the results that the dominant species of BfQ in the LPD silica films is a protonated one. The fluorescence band assigned to a hydrogen-bonded species was observed on the samples prepared from the dipping solutions of 3 and 2 M hexafluorosilicic acid. The band assignment was confirmed by the fluorescence lifetime measurement. The FT-IR M hexaflurosilicic acid. The band assignment was confirmed by the flurescence lifetime meausurement. The FT-IR data proved the existence of included water in silica films prepared from the LPD process. The appearance of the band corresponding to the hydrogen-bonded species within LPD silica phases was explained by the proesence of included water. Depending on the preparation conditions of LPD silica films, the band assigned to protonated species shows bad shifts in a wavenumber region between the peak of hydrogen-bonded and typical protonated species. This implies that there is some distribution of steric conformation of protonated species of BfQ interacting with adsorbing sites of LPD silica. The time -resolved fluorescence spectra suggest that some relaxation process is involved in the conformation of BfQ doped into the solid phase of LPD silica.

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"God Always Find a Way": The Crisis of Civilization and Its Overcoming through the Worldview of Daesoon Jinrihoe

  • CHA Seonkeun
    • Journal of Daesoon Thought and the Religions of East Asia
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    • v.3 no.2
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    • pp.13-34
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    • 2024
  • This article is a compilation of civilizational crises and their overcoming from the worldview of Daesoon Jinrihoe, based on the premise that religion can offer advice on the crises faced by modern civilization. It is a reinterpretation of human history from a religious perspective, focusing on mutual contentions, grievances, grudges, and their overcoming. Daesoon Jinrihoe explains that modern civilizational crises were first recognized by divine beings in the 18th and 19th centuries, and then later recognized by humans in the 20th and 21st centuries. Unable to resolve the civilization crises, the divine beings asked the Supreme God to intervene in human history, and the Supreme God was born in a human body to reveal the root causes and development of various civilizational crise sand to propose solutions to overcome them. These solutions encompass setting the world aright and ushering in a new era through the Reordering Works of Heaven and Earth (天地公事), attaining enduring peace by practicing grievance resolution for mutual beneficence (解冤相生), and reconstructing the relationship between divine beings and humans in harmonious coexistence. Devotees hold that Daesoon Jinrihoe is a religion that originated as a solution to a problem faced by God rather than humankind. As such, it considers the crises of civilization and their overcoming as the reason for existence. According to the religion's worldview, the Supreme God has already provided the solution to these civilizational crises. With a tip of the hat to the film Interstellar (2014), it could be said, "God Found a Way. He Always Has." Now, Daesoon Jinrihoe posits that it is up to humans to implement the way that God found.

A Study on the Preparation and Characterization of $Zn_xSr_{1-x}S$ Thin Films ($Zn_xSr_{1-x}S$ 박막의 제작과 특성에 관한 연구)

  • 이상태
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.5 no.6
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    • pp.1136-1142
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    • 2001
  • $Zn_xSr_{1-x}S$ thin films were prepared in the whole composition range by rf sputtering, using powder targets of a mixture of ZnS and SrS with the required mole fraction. The possibility of existence of $Zn_xSr_{1-x}S$ solid solutions was systematically investigated from the results of thin film growth, in terms of structural, optical characteristics and the chemical bonding of the constituent atoms. The XRD, XPS and optical results made it clear that the solid solutions with a single-phased zincblende structure and a single-phased rocksalt structure were formed at $0.86~0.93{\leq}x{\leq}1\;and\;0{\leq}x{\leq}0.29$, respectively. The miscibility gap, including phase separation regions was found to exist in $0.3{\leq}x{\leq}0.86~0.91$, in which lattice constants, binding energy and absorption edges kept almost constant by the same values as those at border compositions. The experimental results on phase transition agreed well with the fraction of ionic character fi based on the Phillips' dielectric theory.

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A study on the preparation and characterization of $Zn_xSr_{1-x}S$ thin films ($Zn_xSr_{1-x}S$ 박막의 제작과 특성에 관한 연구)

  • 이상태
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2001.10a
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    • pp.660-664
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    • 2001
  • $Zn_xSr_{1-x}S$ thin films were prepared in the whole composition range by rf sputtering, using powder targets of a mixture of ZnS and SrS with the required mole fraction. The possibility of existence of $Zn_xSr_{1-x}S$ solid solutions was systematically investigated from the results of thin film growth, in terns of structural, optical characteristics and the chemical bonding of the constituent atoms. The XRD, XPS and optical results made it clear that the solid solutions with a single-phased zincblende structure and a single-phased rocksalt structure were formed at $0.86~0.93{\leq}x{\leq}1$ and $0{\leq}x{\leq}0.29$, respectively. The miscibility gap, including phase separation regions was found to exist in $0.3{\leq}x{\leq}0.86~0.91$, in which lattice constants, binding energy and absorption edges kept almost constant by the same values as those at border compositions. The experimental results on phase transition agreed well with the fraction of ionic character $f_{i}$ based on the Phillips'dielectric theory.

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Study of Properties of High-K Strontium Oxide Alignment Layer Using Solution Process for Low Power Mobile Information Device (저전력 휴대용 통신단말을 위한 Solution Process를 이용한 고 유전율 Strontium Oxide 배향막의 특성 연구)

  • Han, Jeong-Min;Kim, Won-Bae
    • Journal of Satellite, Information and Communications
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    • v.10 no.2
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    • pp.90-94
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    • 2015
  • We stuidied liauid crystal alignment treatment using solution process for making thin oxide layer in liquid crystal display. It is the one of very effient and popular process in making thin oxide layer in electronical industrial fields. Particularly, this process has highly potential value in liquid crystal display industrial fields because it cause automatically induced alignment process without tranditional alignment process in liquid crystal alignment process. We made several different kinds of mol density solutions using strontium oxide solution. And those solutions were treated for solidification layers using annealing process for 2 hours. And we stuided pretilt angle properties of these alignment layers of strontium oxide for clarifying the relationship of liquid crystal molecules and thin strontium oxide layer. And we also tested the existence of strontium oxide thin layer on substrate using XPS measurement. We expected the hig gain of electro-optical properties in liquid crystal display using strontium oxide thin layer because it has high K property material than the other metal-based oxide layers. In this results, we measured 1.447 to 1.613 thresholds volts as 0.1 mol to 0.4 mol density in 0.1 mol density steps. This is significant better characteristics than conventional liquid crystal display as higher than 1.85 thresholds volts. And it make possible to making next-generation liquid crystal display which present low-power consumption and wide gray scale in liquid crystal display.

Internet Multicast Routing Protocol Supporting Method over MPLS Networks (MPLS망에서의 인터넷 멀티캐스트 라우팅 프로토콜 지원 방안)

  • 김영준;박용진
    • Journal of the Institute of Electronics Engineers of Korea TE
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    • v.37 no.3
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    • pp.93-103
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    • 2000
  • This paper describes Internet multicast routing protocols over MPLS (Multiprotocol Label Switching) networks. Internet multicast routing protocols are divided into 3 categories in terms of tree types and tree characteristics: a shortest path tree, a shared tree and hybrid tree types. MPLS should support various multicast mechanisms because of extremely different IP multicast architectures, such as uni-/bi-directional link, Flooding/prune tree maintenance mechanism, the existence of different tree types with the same group, etc. There are so many problems over MPLS multicast that the solutions can't be easily figured out. In this paper, we make a few assumptions on which the solutions of IP multicast routing protocols over MPLS networks are given. A broadcasting label is defined for the shortest path tree types. Cell interleaving problems of the shared tree types is solved by using block-based transmission mechanism. Finally, the existing hybrid-type multicast routing protocol is reasonably modified to support MPLS multicast.

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Internet Multicast Routing Protocol Model using MPLS Networks (MPLS망을 이용한 인터넷 멀티캐스트 라우팅 프로토콜 모델)

  • Kim, Young-Jun
    • The KIPS Transactions:PartC
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    • v.10C no.1
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    • pp.77-86
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    • 2003
  • This paper describes the new method for Internet multicast routing protocols using MPLS (Multiprotocol Label Switching) networks. Internet multicast routing protocols are divided into three categories in terms if tree types and tree characteristics : a shortest path tree a shared tree and hybrid tree types. MPLS should support various multicast mechanisms because of extremely different IP multicast architectures, such as uni-/bi-directional link, Flooding/prune tree maintenance mechanism. the existence of different tree types with the same group, etc. There are so many problems over MPLS multicast that the solutions can't be easily figured out. In this Paper, we make a few assumptions on which the solutions of IP multicast routing protocols over MPLS networks are given. A broadcasting label is defined for the shortest path tree types. Cell interleaving problems of the shared tree types is solved by using block-based transmission mechanism. Finally, the existing hybrid-type multicast routing protocol is reasonably modified Shortest Path tree type to support MPLS multicast. It has been shown that these modifications give better performance (transmission delay) than the orignal method.

A Study on Definition and Classification System of Wastes (폐기물의 개념 및 분류체계에 관한 연구)

  • Hong, Dong-Hee
    • Journal of Environmental Policy
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    • v.3 no.2
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    • pp.113-137
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    • 2004
  • The objective of this study is to introduce the definitions and classification methods of wastes in international agreements and legislations, examine the concept of wastes and their classification systems in Korea, and finally analyze and compare the concept of wastes in different countries for finding better solutions and suggestions. The study summarizes the concept of wastes as introduced in the Basel Convention, OECD, EU, US, and UK. First, each of the member countries adapt to the same concepts of wastes as defined in their international agreements; second, the intention of the wastes holder and the conditions of the wastes are considered at the same time when defining the concepts. Upon close examination of the classification of wastes systems as introduced in the Basel Convention, OECD, EU, US, and UK, the wastes are classified into toxic and non-toxic wastes according to the existence of poisonous substances. Therefore, it is classified as a toxic waste when any toxic substance on its list is included in the waste, while others are considered as a non-toxic waste if they don't contain poisonous substances. Secondly, in the UK, the matter of toxic or non-toxic wastes are classified, not according to the existence of the poisonous substances, but based on the generation of sources. In Korea, the concepts of wastes are divided into the two categories - a concept as defined in actual legislations and a concept in its translation. The Korean classification of the wastes include Wastes Management Act, amended in 1995, which stipulates that toxic substances should be managed in a special way as the designated wastes. It appears that the Act utilizes the classification method that classifies the wastes according to the existence of poisonous substance. Korea's concepts of wastes should be changed after recognition of the concepts in international agreement (Basel Convention, EU) and other foreign laws(US, UK) that consider subjective and objective standards at the same time when they define the concepts. Also, the development of technology in recycling and reuse of the wastes can remove the current absolute notion of the wastes so that it also should not be passed over. Also, because a classification structure of wastes has a close relationship with a disposal structure, its classification system should be fixed gradually to come up with the development of wastes disposal technology and its policy.

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