• Transactions on Electrical and Electronic Materials
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• 제2권2호
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• pp.5-15
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• 2001

The experiment established optimal conditions for over-carbonization. With the use of the electron microscopy and X-ray phase analysis the regularities of carbon deposit formation in process of methane and propane pyrolysis on the zeolites, Kazakhstan natural clays, chrome and bauxite sludge containing metal oxides of iron subgroup, have been studied. In process of over-carbonization the trivalent iron was reduced to metal form. In addition, the carbon tubes of divers morphology had been impregnated with ultra-dispersed metal particles. The kinetic parameters of carbon formation in process of methane decomposition on the zeolite - CoO mixture surface were investigated by method of thermo-gravimetric analysis. The morphology and structure of formed carbon fibrils, with the metal particles fixed at their ends, have been investigated, the formation of branched carbon fibrils pattern, so called octopus, being found. Also, the walnut shells and grape kernel carbonization, their immobilization by the cells of selective absorption of heavy metal and sulfur dioxide ions have been studied. The example of metal-carbon composites used as adsorbents for wastewater purification, C$_3$- C$_4$ hydrocarbon cracking catalysts and refractory materials with improved properties have been considered.

• Geomechanics and Engineering
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• 제8권2호
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• pp.133-152
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• 2015

Mathematical model has been developed for determination of temperature field in multilayer pavement and subgrade, which considers transfer of heat by conduction and convection, receiving of heat from total solar radiation and atmosphere emission, output of heat due to the emission from the surface of pavement. The developed model has been realized by the finite element method for two dimensional problem using two dimensional second order finite element. Calculations for temperature field have been made with the programme realized on the standard mathematical package MATLAB. Accuracy of the developed model has been evaluated by comparison of temperatures, obtained theoretically and experimentally. The results of comparison showed high accuracy of the model. Long-term calculation (within three months) has been made in pavement points in accordance with the data of meteorological station for air temperature. Some regularities have been determined for variation of temperature field.

• 산업경영시스템학회지
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• 제21권45호
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• pp.101-112
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• 1998

Data mining, which is also referred to as knowledge discovery in database, means a process of nontrivial extraction of implicit, previously unknown and potentially useful information (such as knowledge rules, constraints, regularities) from data in databases. The discovered knowledge can be applied to information management, decision making, and many other applications. In this paper, a new data mining problem, discovering sequential patterns, is proposed which is to find all sequential patterns using sampling method. Recognizing that the quantity of database is growing exponentially and transaction database is frequently updated, sampling method is a fast algorithm reducing time and cost while extracting the trend of customer behavior. This method analyzes the fraction of database but can in general lead to results of a very high degree of accuracy. The relaxation factor, as well as the sample size, can be properly adjusted so as to improve the result accuracy while minimizing the corresponding execution time. The superiority of the proposed algorithm will be shown through analyzing accuracy and efficiency by comparing with Apriori All algorithm.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2005년도 추계학술대회논문집
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• pp.139-142
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• 2005

High speed railway, KTX has started commercial service last you and passengers is increasing. To secure the safety and reliability of high speed railway, it is necessary to inspect and maintain the rail regularities. Several methods of measuring track irregularities are developed in other railway advanced countries. In this paper, we introduce foreign track Inspection methods and application scheme to Koreans.

• 한국멀티미디어학회논문지
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• 제22권9호
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• pp.1132-1139
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• 2019

Big data is prominently used as a prediction method in achieving a goal, because it can analyze the regularities to predict future results from a vast amount of past data. Furthermore, big data has huge influence in very diverse academic fields. On such awareness, this study analyzed the regular effect of e-Commerce usefulness from the effects which expectations on big-data service affect the usage purpose of e-Commerce usefulness. This study categorized e-Commerce usefulness into quality recognition, service, and ease, and studied how each category works between the relationship of big-data service expectation and the use intention.

• 대한수학회지
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• 제59권1호
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• pp.129-150
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• 2022

Let L = -∆ + V be a Schrödinger operator, where the potential V belongs to the reverse Hölder class. In this paper, by the subordinative formula, we investigate the generalized Poisson operator P^L_t,σ, 0 < σ < 1, associated with L. We estimate the gradient and the time-fractional derivatives of the kernel of P^L_t,σ, respectively. As an application, we establish a Carleson measure characterization of the Campanato type space 𝒞^𝛄_L (ℝⁿ) via P^L_t,σ.

• International Journal of Computer Science & Network Security
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• 제21권11호
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• pp.177-180
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• 2021

The theoretical and methodological provisions that allow to systematically and comprehensively study the postgraduate pedagogical education of teachers; the essence and features of postgraduate pedagogical education of teachers of diverse training institutions, providing professional and pedagogical training of this category of pedagogical personnel, have been determined; regularities, principles and conditions for the implementation of promising directions of development of the system of postgraduate pedagogical education for teachers of diverse training have been developed; developed technological support for the development of postgraduate pedagogical education for teachers of multidisciplinary training; identified and substantiated promising directions for the development of postgraduate pedagogical education for teachers of multidisciplinary training in vocational education, due to the modernization.

• 대한화학회지
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• 제9권1호
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• pp.16-22
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• 1965

Sodium alginate-$CaSO_4{\cdot}$1/2 $H_2O$의 gel에 미치는 alkali鹽의 遲延효果를 Miyake date와 比較하고, Schwedoff法을 改良한 連續的 測定方法을 써서, 金屬酸化物의 添加에 依한 彈性 gel의 生成速度 및 彈性의 變化를 硏究하였다. 즉 (1) sample의 張力變化를 連續的으로 測定하여, sodium alginate와 $CaSO_4{\cdot}$1/2 $H_2O$ aqueous sol의 gel化 過程을 觀察하였다. (2) 彈性 gel의 生成速度에 미치는 $Na_3PO_4$의 遲延효果는 $Na_2CO_3$보다 크다는 點에서는 Miyake 報告와 一致하였으나, Miyake date처럼 兩者間에 그리 큰 差가 없었다. (3) 金屬酸化物이 彈性 gel生成速度에 미치는 影響에 어떤 規則性은 없었지마는 $SiO_2$와 MgO는 比較的 큰 速度增大효果를 나타내고 ZnO는 比較的 적었다. 그러나 $Al_2O_3$, $Sb_2O_3$와 $TiO_2$는 速度低下효果를 나타냈다. 結果的으로 酸化物의 種類나 그 添加量에 따라 어떤 明確한 規則性을 觀察하지 못하였다. (4) 彈性率과 生成速度에 미치는 효果사이에 比例關係는 없없으나 金屬酸化物을 添加하면 一般的으로 彈性率이 增加하였다. 이들 酸化物 中에서 彈性率增大효果가 가장 큰 것은 MgO였다.

• 한국농촌건축학회논문집
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• 제4권3호
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• pp.23-37
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• 2002

Buddhist Architecture should be set for worship and an ascetic life, which is its main function as it is a religious facility and its space and form can be considered as means to achieve efficiently a religious function. Every religion concludes its religious function through its ideas and form of faith based on scriptures and religious precepts. The thing should be paid attention to from this point of view is how Buddhist doctrines are reflected on the architecture and the background recognition about the fundamental doctrines and religious system should be preceded to clarify it. Existing researches have studied the characteristics of Buddhist temples on the point of functional view and architectural spacial view through phenomenal ways. Though fruitful results bore about the Korean space through that way, more internal viewpoint is required to clarify the fundamental regularities and spatial concepts indwelling in temple architecture. Considering what structural elements were required to compose one space in traditional Korean architecture is the fundamental subject and important. This thesis searches architectural characteristics through inquiring about the main building and annexes and understanding symbolic characteristics about the arrangement of the Buddhist statue and solemn things in the Buddhist temples of tangible cultural assets or above located in Seoul area.

• Journal of Electrical Engineering and Technology
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• 제12권1호
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• pp.295-301
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• 2017

$SF_6$ decomposition products can be used to detect partial discharge (PD), but the metal materials in a PD area can significantly affect $SF_6$ decomposition characteristics. Disregarding the effect of metal materials on such characteristics inevitably result in certain errors when using them to diagnose the internal insulation faults of gas-insulated switchgears. This paper investigates the influence regularity on the main stable decomposition components of $SF_6$ (namely $SO_2F_2$ and $SOF_2$) of the commonly metal materials uesd in GIS, such as aluminum (Al), copper (Cu) and stainless steel (SS). Firstly, an experimental platform is constructed to simulate $SF_6$ decomposition under a PD area, and the influence regularities of Al, Cu and SS on the concentration, formation rate and saturation time of $SO_2F_2$ and $SOF_2$ are obtained. Secondly, the influence mechanism of Al, Cu and SS are preliminary explored combined with the chemical activity of the metal materials.