• Title/Summary/Keyword: 산학서(算學書)

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Characterization of CO Oxidatation Using the Cu, Mn impregated zeolit 13X catalyst (Cu, Mn 함침 제올라이트13X 촉매의 CO 산화 전환 반응특성)

  • Jung, Eui-Min;Kim, Dae-Kyung;Lee, Joo-Bo;Peng, Mei Mei;Song, Sung-Hwa;Moon, Mi-Mi;Jeon, Lee-Seul;Ahn, Seon-Hee;Jang, Hyun-Tae
    • Proceedings of the KAIS Fall Conference
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    • 2012.05a
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    • pp.30-32
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    • 2012
  • 본 연구에서는 Cu, Mn을 함침 시킨 상용 제올라이트13X 촉매에 CO 산화 전환 반응에 영향을 연구하였다. 촉매 제조는 담지량별로 Cu, Mn을 서로 다른 비율로 물리 혼합하여 상용 제올라이트에 담지하였다. 함침방법은 과잉용액 함침법을 사용하였고, 건조 후 공기분위기에서 소성하여 산화물 형태로 담지하였다. 기본적인 촉매 특성은 X-선 회절분석, 질소흡탈착 등온곡선을 이용하여 기공크기, 기공부피, 비표면적을 구하였으며, FT-IR, 주사현미경, $NH_3$-TPD/TPR, EDX로 특성을 분석하였다. 촉매 산화반응 실험은 고정층 반응기에서 수행하였으며, 외경1/4 inch(내경 4 mm)석영관에 촉매를 중진하고 Gas Chromatograph로 배출가스를 측정하여 Cu-Mn 제올라이트 촉매의 일산화탄소 산화반응을 연구하였다. 일산화탄소 농도, 온도 및 공간속도, Cu-Mn 함량 비율에 따른 산화반응 실험을 수행하여 최적 산화조건과 촉매를 도출하였다.

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A Study on the Differences of Opinion among Groups regarding the Street Landscape in the Old Urban Center -Focused on the Old Urban Center in Gimhae City- (구도심 가로경관에 대한 집단별 인식차이 연구 -김해시 구도심을 중심으로-)

  • Kang, Hye-Won;Seo, You-Seok;Ko, In-Seok
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.14 no.10
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    • pp.5192-5198
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    • 2013
  • The purpose of this study is to investigate the differences of opinion among the user groups in revitalizing the old urban center. To this end, the old downtown commercial street users in Gimhae traders, local and foreign visitors were surveyed. To examine the statistical significance, the chi-square test was performed. There were differences of opinion among three groups about the present condition and improvement of the street. Therefore, in activating the old commercial street we should reflect not only the opinions of merchants but also those of visitors. The results of this study are intended to be used as a reference to the revitalization of old commercial street.

A Study on the Smoking Cessation Self-efficacy and Counseling Satisfaction of University Students Using a University Smoking Cessation Clinic (일부 대학교보건소 금연클리닉 이용 대학생의 자기효능감과 상담만족도)

  • Park, Hyun-Suk
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.14 no.10
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    • pp.5048-5058
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    • 2013
  • This study analyzed the smoking and smoking cessation characteristics, smoking cessation self-efficacy and counseling satisfaction of 140 college students using smoking cessation clinics in 2 universities, located in D Metropolitan City and C Province. The results can be summarized as follow; As motives for signing up for a smoking cessation clinic, 47.8% responded that they were recommended by others. 61.4% said that they had tried to stop smoking for the past one year. As the first reason for stopping smoking, 45.7% responded that it was to prevent diseases in the future. As factors affecting the smoking cessation self-efficacy, the smoking temptation score was the most significant variable, followed by the smoking cessation confidence score and the smoking amount. As a factor affecting the smoking cessation counseling satisfaction, whether to perceive health problems was the most significant variable, followed by the smoking cessation confidence score and the smoking temptation score.

Development of Stiffness Estimation Algorithm for Nonlinear Static Analysis of Bilinear Material Model (전단벽 모형화 방법에 따른 구조해석 신뢰성에 대한 고찰)

  • Jung, Sung-Jin;Park, Se-Hee
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.3
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    • pp.718-723
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    • 2017
  • When structural analysis modelling methods of practical fields are investigated, a slab is generally modeled by a finite element mesh using plate elements and a shear wall is modeled using a shell element or wall element for 3-D structural analysis. The point worthy of notice in this practice is that a shear wall is modelled using only one wall or shell element divided by floors and column lines to produce structural models. The modeling method like this can cause analysis errors according to the type of computer programs in use, and these errors reduce the reliability of the analysis results. Therefore, to secure the reliability of structural analysis, studies of the causes of errors and finding reasonable modeling methods are necessary. In this study, the causes of analysis errors according to the modelling methods of a shear wall, which are used in practical fields, were investigated and some considering matters for modelling a shear wall are presented to reduce the analysis errors on these analysis results.

A Study on Train Braking Performance Assessment Methods Using Braked Weight Percentage (제동중량비율을 이용한 도시철도차량 제동성능 평가방법 연구)

  • Choi, Don-Bum;Lee, Kang-Mi;Yoon, Yong-Ki
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.11
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    • pp.545-551
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    • 2016
  • In this study, we evaluate the braking performance of an urban railway vehicle to verify its basic safety condition. The braking performance evaluation methods, deceleration measurement and braked weight percentage, were compared for trains with different numbers of cars, in order to assess the advantages of each method and their compatibility. With a probabilistic braking model, the effect of the adhesion coefficient distribution was analyzed in accordance with the train composition. A train with many cars has a narrower deceleration distribution width than one with few cars. The braked weight percentage method is expected to be useful in the design of train signal systems, because it allows the braking distance to be calculated for various initial brake velocities. The deceleration distribution model and its results are expected to be useful as a basis for precise train signal design.

Design Optimization Method of Inertial Parameters of Serial Manipulators for Improving the Energy Efficiency (에너지 효율 향상을 위한 직렬형 머니퓰레이터의 관성 파라미터 설계 최적화 방법)

  • Hwang, Soon-Woong;Kim, Hyeon-Guk;Choi, Youn-Sung;Shin, Kyoo-Sik;Han, Chang-Soo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.11
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    • pp.395-402
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    • 2016
  • This paper presents a design methodology for improving the energy efficiency by considering the inertial properties of serial manipulators. This method employed is to put the inertia matrix, which has a critical effect on the equation of motion, into the constraints of the optimization problem. Through the optimization process, we propose a design algorithm that can double-check whether the optimized parameters satisfy the required performance or not by using an auxiliary index associated with the inertia and energy. Using this design algorithm, we were able to improve the energy efficiency by minimizing the torque. We applied this method to a 3 degrees of freedom serial manipulator and simulated it.

The Study on the Graded Index Antireflection(AR) Coating (구배형 굴절률 반사방지막 연구)

  • Kim, Chang-Bong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.5
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    • pp.565-570
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    • 2017
  • The various techniques proposed previously to obtain a good antireflection(AR) coating induce a scattering of incident light by nanoparticles or control the refractive index by using different materials. This paper compares a suggested graded index profile with the quintic index profile previously suggested for producing an index profile that gives good performance from an AR coating. We assume the structure of the AR coating has three, six, and nine layers with 180 nm total thickness. The wavelength of incident light ranges from 300 nm to 1100 nm. We use the transfer matrix theory for a single layer to obtain the reflectivity of three, six, and nine layers. The reflectivity of two different index profiles with three, six, and nine layers is compared. As a result, the suggested graded index profile shows lower reflectivity than the quintic index profile with three layers, especially in the wavelength range from about 600 nm to 1100 nm. Therefore, we expect that these results can be applied to optical devices and filters in the range from visible(red) to near infrared.

Improvement of Frame Rate of Electro-Optical Sensor using Temporal Super Resolution based on Color Channel Extrapolation (채널별 색상정보 외삽법 기반 시간적 초해상도 기법을 활용한 전자광학 센서의 프레임률 향상 연구)

  • Noh, SangWoo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.5
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    • pp.120-124
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    • 2017
  • The temporal super resolution is a method for increasing the frame rate. Electro-optical sensors are used in various surveillance and reconnaissance weapons systems, and the spatial resolution and temporal resolution of the required electro-optical sensors vary according to the performance requirement of each weapon system. Because most image sensors capture images at 30~60 frames/second, it is necessary to increase the frame rate when the target moves and changes rapidly. This paper proposes a method to increase the frame rate using color channel extrapolation. Using a DMD, one frame of a general camera was adjusted to have different consecutive exposure times for each channel, and the captured image was converted to a single channel image with an increased frame rate. Using the optical flow method, a virtual channel image was generated for each channel, and a single channel image with an increased frame rate was converted to a color channel image. The performance of the proposed temporal super resolution method was confirmed by the simulation.

Finite Element Modeling Method for SRM Design (SRM 설계를 위한 유한 요소 모델링 기법)

  • Bae, Jae-Nam;Lee, Sung-Gul;Kim, Won-Ho
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.4
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    • pp.586-592
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    • 2018
  • SRMs are difficult to design using a simple mathematical model and, consequently, numerical analysis based characteristics analysis is used including drive circuits. In this process, it is necessary to analyze the trends according to the change of the design factors, however, many of the design factors affect each other. In order to shorten the design time and achieve a proper design, a modeling technique based on the design parameters is needed. For this purpose, this paper summarizes the formulas employed for shape modeling by minimizing the number of major design factors of the SRM, and proposes a methodology for SRM design using these formulas. In particular, we propose a design method for a 6/4-pole model, one which has been studied for a long time, and showed an example of a design produced by the proposed method.

A Design of A Modbus Application Protocol for Multiple SCU Connections (다중 제어 장치 연결을 위한 Modbus 응용 Protocol 설계)

  • Song, Jeong-Ho;Kim, Bo-Hun;Kim, Hwang-Rae
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.4
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    • pp.642-649
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    • 2018
  • The Modbus protocol is the most widely used protocol for connecting multiple slave control units (SCUs) in the master control unit. However, the Modbus protocol does not identify which SCU response message corresponds to the service request message. Therefore, when using the Modbus protocol, one service request message can be transmitted after processing the previous message. In this paper, we propose a Modbus application protocol with an index code and a service code to solve the problem. As a result of experimentation, it is possible to transmit the next service request message without processing the previous service request message. And when a communications error occurs, it is possible to identify what type of error occurred using an error detection algorithm. Also, with simultaneous multiple service requests, the proposed protocol can improve processing time by about 66.2%, compared to the original Modbus protocol.