• Title/Summary/Keyword: chain rule

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Kinetic Study on the Thermal Degradation of Poly(Methyl Methacrylate) and Poly(Acrylonitrile Butadiene Styrene) Mixtures (Poly(methyl methacrylate)와 Poly(acrylonitrile butadiene styrene)와의 혼합에 의한 열분해속도에 관한 연구)

  • Moon, Deok-Ju;Kim, Dong-Keun;Seul, Soo-Duk
    • Elastomers and Composites
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    • v.24 no.1
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    • pp.11-18
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    • 1989
  • The thermal degradation of Poly(methyl methacrylate) (PMMA) and poly(acrylonitrile butadiene styrene)(ABS) terpolymer as well as their mixtures were carried out using the thermogravimetry and differential scanning calorimetry(DSC) in the stream of nitrogen and air with 50 ml/min at the various heating rate from 4 to $20^{\circ}C/min$ and temperature from 200 to $300^{\circ}C$ The values of activation energies of thermal degradation determined by TG and DSC in the various PMMA/ABS mixtures were $34{\sim}58Kcal/mol,\;35{\sim}54Kcal/mol$ in the stream of nitrogen. The values of activation energy of ABS20% mixture was appeared high in camparison with addition rule. According to increasing the composition of ABS, the temperatures of glass transition and initial decomposition temperature were increased. PMMA/ABS mixtures by the analysis of infrared spectrophotometer were decomposed by main chain scission in the stream of nitrogen.

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An Innovative Approach of Bangla Text Summarization by Introducing Pronoun Replacement and Improved Sentence Ranking

  • Haque, Md. Majharul;Pervin, Suraiya;Begum, Zerina
    • Journal of Information Processing Systems
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    • v.13 no.4
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    • pp.752-777
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    • 2017
  • This paper proposes an automatic method to summarize Bangla news document. In the proposed approach, pronoun replacement is accomplished for the first time to minimize the dangling pronoun from summary. After replacing pronoun, sentences are ranked using term frequency, sentence frequency, numerical figures and title words. If two sentences have at least 60% cosine similarity, the frequency of the larger sentence is increased, and the smaller sentence is removed to eliminate redundancy. Moreover, the first sentence is included in summary always if it contains any title word. In Bangla text, numerical figures can be presented both in words and digits with a variety of forms. All these forms are identified to assess the importance of sentences. We have used the rule-based system in this approach with hidden Markov model and Markov chain model. To explore the rules, we have analyzed 3,000 Bangla news documents and studied some Bangla grammar books. A series of experiments are performed on 200 Bangla news documents and 600 summaries (3 summaries are for each document). The evaluation results demonstrate the effectiveness of the proposed technique over the four latest methods.

A Study on the Implications and Trends of Logistics Security Assurance Programs for International Trade Facilitation (국제물류보안 인증제도 동향 및 시사점에 관한 연구)

  • Ko, Hyun-Jeung
    • Journal of Korea Port Economic Association
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    • v.27 no.2
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    • pp.333-354
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    • 2011
  • After the terrorist attack of 9/11 on the USA, the security concern to global trade has been raised. In particular, the USA has actively promoted a series of initiatives and rules such as CSI, 24 hour rule, C-TPAT, and so on in the area of logistics activities, which aimed to better protect the country against the potential terrorist threats. While implementing such schemes called as a multi-layed logistics security strategy, a large number of countries trading with USA are facing with the issues of additional time and costs for inspecting cargos in their logistics facilities. As a result, most countries all over the world have sought a way to minimize the impacts from such strategy. The Korea also is preparing the several security programs operated by various ministries, which are aiming to not only improve the efficiency of trade flows but also to ensure supply chain security. However, many companies are expressing the inefficiency of operating such programs. Thus, this paper analyzed several global supply chain security programs currently adopted by international organizations(ISO, WCO, and IMO) and major countries(USA, EU, and Singapore) and suggested a guideline for developing the national logistics security system.

A new feature specification for vowel height (모음 높이의 새로운 표기법에 대하여)

  • Park Cheon-Bae
    • MALSORI
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    • no.27_28
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    • pp.27-56
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    • 1994
  • Processes involving the change of vowel height are natural enough to be found in many languages. It is essential to have a better feature specification for vowel height to grasp these processes properly, Standard Phonology adopts the binary feature system, and vowel height is represented by the two features, i.e., [\pm high] and [\pm low]. This has its own merits. But it is defective because it is misleading when we count the number of features used in a rule to compare the naturalness of rules. This feature system also cannot represent more than three degrees of height, We wi31 discard the binary features for vowel height. We consider to adopt the multivalued feature [n high] for the property of height. However, this feature cannot avoid the arbitrariness resulting from the number values denoting vowel height. It is not easy to expect whether the number in question is the largest or not It also is impossible to decide whether a larger number denotes a higher vowel or a lower vowel. Furthermore this feature specification requires an ad hoc condition such as n > 3 or n \geq 2, whenever we want to refer to a natural class including more than one degree of height The altelnative might be Particle Phonology, or Dependency Phonology. These might be apt for multivalued vowel height systems, as their supporters argue. However, the feature specification of Particle Phonology will be discarded because it does not observe strictly the assumption that the number of the particle a is decisive in representing the height. One a in a representation can denote variant degrees of height such as [e], [I], [a], [a ] and [e ]. This also means that we cannot represent natural classes in terms of the number of the particle a, Dependency Phonology also has problems in specifying a degree of vowel height by the dependency relations between the elements. There is no unique element to represent vowel height since every property has to be defined in terms of the dependency relations between two or more elements, As a result it is difficult to formulate a rule for vowel height change, especially when the phenomenon involves a chain of vowel shifts. Therefore, we suggest a new feature specification for vowel height (see Chapter 3). This specification resorts to a single feature H and a few >'s which refer exclusively to the degree of the tongue height when a vowel is pronounced. It can cope with more than three degrees of height because it is fundamentally a multivalued scalar feature. This feature also obviates the ad hoc condition for a natural class while the [n high] type of multivalued feature suffers from it. Also this feature specification conforms to our expection that the notation should become simpler as the generality of the class increases, in that the fewer angled brackets are used, the more vowels are included, Incidentally, it has also to be noted that, by adopting a single feature for vowel height, it is possible to formulate a simpler version of rules involving the changes of vowel height especially when they involve vowel shifts found in many languages.

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The Substates with Mutants That Negatively Charged Aspartate in Position 172 Was Replaced with Positive Charge in Murine Inward Rectifier Potassium Channel (Murine Kir2.1)

  • So, I.;Ashmole, I.;Stanfield, P.R.
    • The Korean Journal of Physiology and Pharmacology
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    • v.7 no.5
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    • pp.267-273
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    • 2003
  • We have investigated the effect on inducing substate(s) of positively charged residues replaced in position 172 of the second transmembrane domain in murine inward rectifier potassium channels, formed by stable or transient transfection of Kir2.1 gene in MEL or CHO cells. Single channel recordings were obtained from either cell-attached patches or inside-out patches excised into solution containing 10 mM EDTA to rule out the effect of $Mg^{2+}$ on the channel gating. The substate(s) could be recorded with all mutants D172H, D172K and D172R. The unitary current-voltage (I-V) relation was not linear with D172H at $pH_i$ 6.3, whereas the unitary I-V relation was linear at $pH_i$ 8.0. The relative occupancy at $S_{LC}$ was increased from 0.018 at $pH_i$ 8.0 to 0.45 at $pH_i$ 5.5. In H-N dimer, that was increased from 0.016 at $pH_i$ 8.0 to 0.23 at $pH_i$ 5.5. The larger the size of the side chain or $pK_a$ with mutants (D172H, D172K and D172R), the more frequent the transitions between the fully open state and substate within an opening. The conductance of the substate also depended upon the pKa or the size of the side chain. The relative occupancy at substate $S_{LC}$ with monomer D172K (0.50) was less than that in K-H dimer (0.83). However, the relative occupancy at substate with D172R (0.79) was similar to that with R-N dimer (0.82). In the contrary to ROMK1, positive charge as well as negative charge in position 172 can induce the substate rather than block the pore in murine Kir2.1. The single channel properties of the mutant, that is, unitary I-V relation, the voltage dependence of the mean open time and relative occupancy of the substates and the increased latency to the first opening, explain the intrinsic gating observed in whole cell recordings.

Study on frequency response of implantable microphone and vibrating transducer for the gain compensation of implantable middle ear hearing aid (이식형 마이크로폰과 진동체를 갖는 인공중이의 이득 보상을 위한 주파수 특성 고찰)

  • Jung, Eui-Sung;Seong, Ki-Woong;Lim, Hyung-Gyu;Lee, Jang-Woo;Kim, Dong-Wook;Lee, Jyung-Hyun;Kim, Myoung-Nam;Cho, Jin-Ho
    • Journal of Sensor Science and Technology
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    • v.19 no.5
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    • pp.361-368
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    • 2010
  • ACROSS device, which is composed of an implantable microphone, a signal processor, and a vibrating transducer, is a fullyimplantable middle ear hearing device(F-IMEHD) for the recovery of patients with hearing loss. And since a microphone is implanted under skin and tissue at the temporal bones, the amplitude of the sound wave is attenuated by absorption and scattering. And the vibrating transducer attached to the ossicular chain caused also the different displacement from characteristic of the stapes. For the gain control of auditory signals, most of implantable hearing devices with the digital audio signal processor still apply to fitting rules of conventional hearing aid without regard to the effect of the implanted microphone and the vibrating transducer. So it should be taken into account the effect of the implantable microphone and the vibrating transducer to use the conventional audio fitting rule. The aim of this study was to measure gain characteristics caused by the implanted microphone and the vibrating transducer attached to the ossicle chains for the gain compensation of ACROSS device. Differential floating mass transducers (DFMT) of ACROSS device were clipped on four cadaver temporal bones. And after placing the DFMT on them, displacements of the ossicle chain with the DFMT operated by 1 $mA_{peak}$ current was measured using laser Doppler vibrometer. And the sensitivity of microphones under the sampled pig skin and the skin of 3 rat back were measured by stimulus of pure tones in frequency from 0.1 to 8.9 kHz. And we confirmed that the microphone implanted under skin showed poorer frequency response in the acoustic high-frequency band than it in the low- to mid- frequency band, and the resonant frequency of the stapes vibration was changed by attaching the DFMT on the incus, the displacement of the DFMT driven with 1 $mA_{rms}$ was higher by the amount of about 20 dB than that of cadaver's stapes driven by the sound presssure of 94 dB SPL in resonance frequency range.

In Situ-DRIFTS Study of Rh Promoted CuCo/Al2O3 for Ethanol Synthesis via CO Hydrogenation

  • Li, Fang;Ma, Hongfang;Zhang, Haitao;Ying, Weiyong;Fang, Dingye
    • Bulletin of the Korean Chemical Society
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    • v.35 no.9
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    • pp.2726-2732
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    • 2014
  • The promoting effect of rhodium on the structure and activity of the supported Cu-Co based catalysts for CO hydrogenation was investigated in detail. The samples were characterized by DRIFTS, $N_2$-adsorption, XRD, $H_2$-TPR, $H_2$-TPD and XPS. The results indicated that the introduction of rhodium to Cu-Co catalysts resulted in modification of metal dispersion, reducibility and crystal structure. DRIFTS results of CO hydrogenation at reaction condition (P=2 MPa, $T=260^{\circ}C$) indicated the addition of 1 wt % rhodium improved hydrogenation ability of Cu-Co catalysts. The ethanol selectivity and CO conversion were both improved by 1 wt % Rh promoted Cu-Co based catalysts. The alcohol distribution over un-promoted and rhodium promoted Cu-Co based catalysts obeys A-S-F rule and higher chain growth probability was got on rhodium promoted catalyst.

Stock investment with a redistribution model of the history-dependent Parrondo game (과거의존 파론도 게임의 재분배 모형을 이용한 주식 투자)

  • Jin, Geonjoo;Lee, Jiyeon
    • Journal of the Korean Data and Information Science Society
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    • v.26 no.4
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    • pp.781-790
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    • 2015
  • The Parrondo paradox is the counter-intuitive phenomenon: when we combine two losing games we can win the game or when we combine two winning games we can lose the game. In this paper, we assume that an investor adopts the rule of the history-dependent Parrondo game for investment in the stock market. Using the KRX (Korea Exchange) data from 2012 to 2014, we found the Parrondo paradox in the stock trading: the redistribution of profits among accounts can turn the decrease of the expected cumulative profit into the increase of the expected cumulative profit. We also found that the opposite case, namely the reverse Parrondo effect, can happen in the stock trading.

Main Revisions and Some Recommendations of the Incoterms(R) 2010 (인코텀즈 2010의 주요 개정내용과 적용상의 유의점)

  • Choi, Myung-Kook
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.49
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    • pp.3-41
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    • 2011
  • In this article, the author have studied on main revisions and some recommendations of the Incoterms(R) 2010. Main revisions are as belows. 1. Two new Incoterms rules -DAT and DAP- have replaced the Incoterms 2000 rules DAF, DES, DEQ and DDU. 2. New classification of the Incoterms(R) 2010 are adopted. First class is Rules for any mode or modes of transport(EXW, FCA, CPT, CIP, DAT, DAP and DDP belong to this class.) and second class is rules for sea and inland waterway transport(FAS, FOB, CFR and CIF belong to this class.). 3. Incoterms(R) 2010 rules formally recognizes that they are available for application to both international and domestic sale contracts. 4. The Guidance Notes and Introduction are not part of the actual Incoterms(R) 2010 rules. 5. Under the FOB, CFR and CIF, all mention of the ship's rail as the point of delivery has been omitted in preference for the goods being delivered when they are "on board" the vessel. 6. Incoterms(R) 2010 rules include the obligation to 'procure goods shipped' as an alternative to the obligation to ship goods in the relevant Incoterms rules. 7. Incoterms(R) 2010 rules give electronic means of communication the same effect as paper communication. 8. Incoterms(R) 2010 rules have allocated obligations between the buyer and seller to obtain or to render assistance in obtaining security-related clearances. such as chain-of custody information. Some recommendations are as belows. 1. The parties must incorporate the Incoterms(R) 2010 rules into their contract of sale. 2. The parties must choose the appropriate Incoterms(R) 2010 rules. 3. Specify the place or port as precisely as possible in their contract of sale. 4. Remember that Incoterms(R) 2010 rules do not give the parties a complete contract of sale. 5. Incoterms(R) 2010 rules do not prohibit alteration of Incoterms rule, but there are dangers in so doings. In order to avoid any unwelcome surprises, the parties would need to make the intended effect of such alterations extremely clear in their contract.

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Recent results on the analysis of viscoelastic constitutive equations

  • Kwon, Youngdon
    • Korea-Australia Rheology Journal
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    • v.14 no.1
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    • pp.33-45
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    • 2002
  • Recent results obtained for the port-pom model and the constitutive equations with time-strain separability are examined. The time-strain separability in viscoelastic systems Is not a rule derived from fundamental principles but merely a hypothesis based on experimental phenomena, stress relaxation at long times. The violation of separability in the short-time response just after a step strain is also well understood (Archer, 1999). In constitutive modeling, time-strain separability has been extensively employed because of its theoretical simplicity and practical convenience. Here we present a simple analysis that verifies this hypothesis inevitably incurs mathematical inconsistency in the viewpoint of stability. Employing an asymptotic analysis, we show that both differential and integral constitutive equations based on time-strain separability are either Hadamard-type unstable or dissipative unstable. The conclusion drawn in this study is shown to be applicable to the Doi-Edwards model (with independent alignment approximation). Hence, the Hadamardtype instability of the Doi-Edwards model results from the time-strain separability in its formulation, and its remedy may lie in the transition mechanism from Rouse to reptational relaxation supposed by Doi and Edwards. Recently in order to describe the complex rheological behavior of polymer melts with long side branches like low density polyethylene, new constitutive equations called the port-pom equations have been derived in the integral/differential form and also in the simplifled differential type by McLeish and carson on the basis of the reptation dynamics with simplifled branch structure taken into account. In this study mathematical stability analysis under short and high frequency wave disturbances has been performed for these constitutive equations. It is proved that the differential model is globally Hadamard stable, and the integral model seems stable, as long as the orientation tensor remains positive definite or the smooth strain history in the flow is previously given. However cautious attention has to be paid when one employs the simplified version of the constitutive equations without arm withdrawal, since neglecting the arm withdrawal immediately yields Hadamard instability. In the flow regime of creep shear flow where the applied constant shear stress exceeds the maximum achievable value in the steady flow curves, the constitutive equations exhibit severe instability that the solution possesses strong discontinuity at the moment of change of chain dynamics mechanisms.