• Title/Summary/Keyword: CBM

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An Effective Carrier-Based Modulation Strategy to Reduce the Switching Losses for Indirect Matrix Converters

  • Tran, Quoc-Hoan;Lee, Hong-Hee
    • Journal of Power Electronics
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    • v.15 no.3
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    • pp.702-711
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    • 2015
  • In this paper, an effective carrier-based modulation (CBM) strategy to reduce the switching losses for indirect matrix converters (IMCs) is presented. The discontinuous pulse width modulation method is applied to decrease the switching numbers in one carrier cycle, and an optimum offset voltage is selected to avoid commutations of the high output phase currents. By decreasing the switching numbers along with avoiding commutation of the high currents, the proposed CBM strategy significantly reduces the switching losses in IMCs. In addition, the proposed CBM strategy is independent of load conditions, such as load power and power factor, and it has good performance in terms of the input/output waveforms. Simulation and experimental results are provided to verify the effectiveness of the proposed CBM strategy.

Implementation of Collaboration Distance Guarding System based CBM(Computer Based Multimedia) (CBM 기반의 상호참여형 원격 방범시스템 구현)

  • 김석수;신광철
    • Journal of the Korea Society of Computer and Information
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    • v.3 no.2
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    • pp.161-168
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    • 1998
  • This paper proposes the distance-video-guarding system technology based on collaboration CBM personal computer which enables additional functions such as monitoring each room while the guarding is in progress. This system sends the atmosphere of guarding by checking the status of environment with the sensor using ISDN. Current remote guarding desktop system uses leased lines (T1/E1 ) applying fast speed rate and security. This system provides an external monitoring system which runs on ISDN Public line also. Monitoring system transfers the natural status of each site to center controller of the guarding system.

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Analysis Procedure For CBM Using Web-Log (웹 로그를 이용한 고객행동모델 분석방법에 관한 연구)

  • 서장훈;박명규
    • Journal of the Korea Safety Management & Science
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    • v.4 no.4
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    • pp.119-128
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    • 2002
  • In this report, we provide the focus on suggesting a method of estimating and measurement of CBM(Customer Behavior Model). Through the use of internet, a new trend of business for e-CRM on B2C Web Site known as EC has emerged. The purpose of this study is to identify the relationship between the customers of a shopping mall and CBM characteristics. It can be used to gain a better understanding of customers. from this we can determine trends, and so refine business toward customer's needs and target new products to particular customer groups. Result shows that there is a significant relationship between the customers pattern of shopping mall and CBM, CVM(Customer Visit Model).

Effect of Capsella bursa-pastoris (L.) Medicus on fermentation of Kimchi (배추김치 발효에 미치는 냉이의 첨가 효과)

  • Lee, Shin-Ho
    • Journal of the East Asian Society of Dietary Life
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    • v.16 no.5
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    • pp.559-563
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    • 2006
  • This research was performed to investigate the potential use of Capsella bursa-pastoris (L.) as an ingredient to improve the biological function and flavor of kimchi. The quality characteristics were studied for kimchi with or without Capsella bursa-pastoris (L.) Medicus (CBM kimchi) during fermentation for 25 days at $10^{\circ}C$. The pH changes of CBM kimchi were slower than those of control but did not show any significant difference after addition of Capsella bursa-pastoris (L.) Medicus during fermentation. The titratable acidity of CBM kimchi was higher than that of control. The log number of total bacteria was lower about 1.5 $log_{10}$ cycle in CBM kimchi than in control during fermentation. However, lactic acid bacteria did not show significant difference between CMB kimchi and control. Sensory qualities of kimchi such as color, taste, flavor and overall acceptability were significantly improved by addition of 3% Capsella bursa-pastoris (L.) Medicus(p<0.05).

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Influence of complex geological structure on horizontal well productivity of coalbed methane

  • Qin, Bing;Shi, Zhan-Shan;Sun, Wei-Ji;Liang, Bing;Hao, Jian-Feng
    • Geomechanics and Engineering
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    • v.29 no.2
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    • pp.145-154
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    • 2022
  • Complex geological conditions have a great influence on the mining of coalbed methane (CBM), which affects the extraction efficiency of CBM. This investigation analyzed the complicated geological conditions in the Liujia CBM block of Fuxin. A geological model of heterogeneities CBM reservoirs was established to study the influence of strike direction of igneous rocks and fault structures on horizontal well layout. Subsequently, the dual-porosity and dual-permeability mathematical model was established, which considers the dynamic changes of porosity and permeability caused by gas adsorption, desorption, pressure change. The results show that the production curve is in good agreement with the actual by considering gas seepage in matrix pores in the model. Complicated geological structures affect the pressure expansion of horizontal wells, especially, the closer to the fault structure, the more significant the effect, the slower the pressure drop, and the smaller the desorption area. When the wellbore extends to the fault, the pressure expansion is blocked by the fault and the productivity is reduced. In the study area, the optimal distance to the fault is 70 m. When the horizontal wellbore is perpendicular to the direction of coal seam igneous rock, the productivity is higher than that of parallel igneous rock, and the horizontal well bore should be perpendicular to the cleat direction. However, the well length is limited due to the dense distribution of igneous rocks in the Liujia CBM block. Therefore, the horizontal well pumping in the study area should be arranged along the direction of igneous rock and parallel plane cleats. It is found that the larger the area surrounded by igneous rock, the more favorable the productivity. In summary, the reasonable layout of horizontal wells should make full use of the advantages of igneous rock, faults and other complex geological conditions to achieve the goal of high and stable production.

A Study on the Establishment of Cybercrime Business Model(CBM) through a Systematic Literature Review (체계적 문헌 연구를 통한 사이버범죄 비즈니스 모델(CBM) 구축)

  • Park, Ji-Yong;Lee, Heesang
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.6
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    • pp.646-661
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    • 2020
  • Technological innovations and fast-growing new internet businesses are changing the paradigm of traditional business management, having various impacts on society. The development of internet technology is also increasing the adverse effects on technological innovation, and in particular, cybercrime related to computers continues to increase with each technological innovation. The purpose of this study is to construct a cybercrime business model (CBM) by using the business model canvas (BMC) theory for cybercrime in order to reduce cybercrime, and this model is applied and analyzed based on types of Korean cybercrimes. For this study, a systematic literature review was conducted to determine the components of cybercrime, and 60 relevant documents were classified through a keyword-based literature search. Besides, qualitative research in the classified literature has led to the derivation of cybercrime into 18 sub-blocks and nine building blocks. This study applies BMC theory to this derivation of cybercrime and builds the CBM through proper redefinition. Lastly, the developed CBM could be applied to cybercrime in Korea to help cyber incident-response staff understand cybercrimes analytically. This study contributes to the development of a new analysis framework that can reduce cybercrime.

Effect of the light qualities on the growth characteristics and yield in the cultivation of Lyophyllum ulmarium (만가닥버섯 재배시 광 종류에 따른 생육 특성 및 수량)

  • Park, Jae-Seong;Choi, Jae-Sun;Rho, Chang-Woo;Yun, Tae;Lee, Chang-Soo
    • Journal of Mushroom
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    • v.8 no.4
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    • pp.137-141
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    • 2010
  • This experiment was carried out to clarify the effect of light qualities on the growth characteristics and yield of fruiting body in the cultivation of Lyophyllum ulmarium. The intensity of illumination by light qualities was in the order of white light(2,270Lux), yellow light(1,750Lux), blue light(460Lux) and red light(400Lux). An investigation of fruiting body showed these results that the pileus size and stipe diameter of fruiting body on CBM(Chungbuk mushroom)-1757 were much larger than Hypsizigus marmoreus, and an effect of yellow light seemed to be better than those of another light. In comparison with Hypsizigus marmoreus, the growth duration of CBM-1757 was shortened by 8 days which included 2 days for mycelial culture, 1 day for first pinning requirement and 1 day for growth. The growth duration in yellow light illumination was about 70 days showing the tendency of 2~4 days reduction. There were no differences in results such as number of effective stem and fresh weight. The yield of fruiting body per bottle in CBM-1757(95.6g) was little higher than Hypsizigus marmoreus(94.8g). By a white light's standard, the yields of blue and red light illumination were decreased by 2~9%, but that of yellow light illumination was increased by 8%. The chromaticity results showed that brightness, red and yellow coloration of CBM-1757 were higher than those of Hypsizigus marmoreus, and yellow light treatment was more effective than another light.

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Comparison of Textural Properties of Crab-flavored Sausage with Different Proportions of Chicken Meat (원료육의 혼합비율에 따른 게맛 어육소시지의 조직학적 및 관능적 특성)

  • Jin, Sang-Keun;Kim, Il-Suk;Nam, Young-Wook;Park, Seong-Chan;Choi, Seung-Yun;Yang, Han-Sul;Choi, Young-Joon
    • Food Science of Animal Resources
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    • v.28 no.4
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    • pp.395-400
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    • 2008
  • This study was carried out to compare the textural properties of crab-flavored sausage manufactured with six different formulations. We prepared crab-flavored sausage from Alaska pollack surimi as a control by the washing method, and various mixtures of surimi and chicken breast meat were manufactured (pH 11.0) with 33.33% chicken breast meat (CBM) (T1), 50% CBM (T2), 66.66% CBM (T3), 100% CBM (T4) and 20% commercial mechanically deboned chicken meat (MDCM) (T5). Brittleness, gumminess, chewiness, breaking force, gel strength, jelly strength, sensory flavor. texture, and overall acceptability were significantly lower in the formulations containing chicken meat in proportion to the % CBM (p<0.05). However, cohesiveness and springiness were significantly higher in the formulations containing chicken meat in proportion to the amount of CBM (p<0.05). Folding test and deformation values were significantly lower in the surimi manufactured with CBM at pH 11.0. although T5 showed no significant differences relative to the control. Overall, these results indicate that similar textural properties in the crab-flavored sausage were attained when surimi was prepared with 20% CBM and MDCM.

5 DOF Home Robot Arm based on Counterbalance Mechanism (기계식 중력보상 기반의 가정용 5자유도 로봇 팔)

  • Park, Hui Chang;Ahn, Kuk Hyun;Min, Jae Kyung;Song, Jae-Bok
    • The Journal of Korea Robotics Society
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    • v.15 no.1
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    • pp.48-54
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    • 2020
  • Home robot arms require a payload of 2 kg to perform various household tasks; at the same time, they should be operated by low-capacity motors and low-cost speed reducers to ensure reasonable product cost. Furthermore, as robot arms on mobile platforms are battery-driven, their energy efficiency should be very high. To satisfy these requirements, we designed a lightweight counterbalance mechanism (CBM) based on a spring and a wire and developed a home robot arm with five degrees of freedom (DOF) based on this CBM. The CBM compensates for gravitational torques applied to the two pitch joints that are most affected by the robot's weight. The developed counterbalance robot adopts a belt-pulley based parallelogram mechanism for 2-DOF gravity compensation. Experiments using this robot demonstrate that the CBM allows the robot to meet the above-mentioned requirements, even with low-capacity motors and speed reducers.

Pre-feasibility Study in Mongolia Tavan Tolgoi Coal Bed Methane (Tavan Tolgoi Coal Bed Methane에 대한 몽골에서의 타당성 조사)

  • CHO, WONJUN;YU, HYEJIN;LEE, JESEOL;LEE, HYUN CHAN;JU, WOO SUNG;LIM, OCKTAEK
    • Transactions of the Korean hydrogen and new energy society
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    • v.29 no.1
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    • pp.124-129
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    • 2018
  • Methane is the cleanest fuel and supplies by many distributed type: liquefaction natural gas (LNG), compressed natural gas (CNG), and pipeline natural gas (PNG). Natural gas is mainly composed by methane and has been discovered in the oil and gas fields. Coal bed methane (CBM) is also one of them which reserved in coalbed. This significant new energy sources has emerge to convert an energy source, hydrogen and hydrogen-driven chemicals. For this CBM, this paper was written to analyze the geological analysis and reserves in Mongolian Tavan Tolgoi CBM coal mine and to examine the application field. This paper is mainly a preliminary feasibility report analyzing the business of Tavan Tolgoi CBM and its exploitable gas.