• 제목/요약/키워드: inexpensive

검색결과 1,271건 처리시간 0.026초

Dual compasses를 이용한 스프레더의 자세 제어 (Spreader Pose Control Using Dual-electric Compasses)

  • 한순신;정희석;이장명
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2007년도 심포지엄 논문집 정보 및 제어부문
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    • pp.366-368
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    • 2007
  • A spreader pose control system using dual-electric compasses has been implemented by measuring the skew angle of the spreader with dual-electric compasses. In the conventional spreader pose measurement, CCD cameras, laser sensors or tilt sensors are mostly used. However those sensors are not only sensitive to the weather and disturbances but also expensive to build the system. To overcome the shortcomings, an inexpensive and efficient system to control the spreader pose has been implemented using the dual-magnetic compasses. Since the spreader iron-structures are noise sources to the magnetic compass, it is not considered to use the magnetic compass to measure the orientation of the spreader. An algorithm to eliminate the interferences of metal structures to the dual compasses has been developed in this paper. The 10:1 reduction model of a spreader control system is implemented and the control performance is demonstrated to show the effectiveness of the dual-magnetic compasses proposed in this research.

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ESD에 의한 반도체소자의 손상특성 (Damage and Failure Characteristics of Semiconductor Devices by ESD)

  • 김두현;김상렬
    • 한국안전학회지
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    • 제15권4호
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    • pp.62-68
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    • 2000
  • Static electricity in electronics manufacturing plants causes the economic loss, yet it is one of the least understood and least recognized effects haunting the industry today. Today's challenge in semiconductor devices is to achieve greater functional density pattern and to miniaturize electronic systems of being more fragile by electrostatic discharges(ESD) phenomena. As the use of automatic handling equipment for static-sensitive semiconductor components is rapidly increased, most manufacturers need to be more alert to the problem of ESD. One of the most common causes of electrostatic damage is the direct transfer of electrostatic charge from the human body or a charged material to the static-sensitive devices. To evaluate the ESD hazards by charged human body and devices, in this paper, characteristics of electrostatic attenuation in domestic semiconductor devices is investigated and the voltage to cause electronic component failures is investigated by field-induced charged device model(FCDM) tester. The FCDM simulator provides a fast and inexpensive test that faithfully represents ESD hazards in plants. Also the results obtained in this paper can be used for the prevention of semiconductor failure from ESD hazards.

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A Study of the Real-time Sensing by the Optical Current Sensor for GIS

  • Park, Won-Zoo;Kim, Yeong-Min
    • 조명전기설비학회논문지
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    • 제23권7호
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    • pp.75-80
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    • 2009
  • In this study, a Web server was constructed using LabVIEW's DataSocket, which makes possible acquisition, analysis, and saving in real time. The output value of the optical current sensor at the web server PC was measured and the output value was displayed using the Web browser of the client PC. DataSocket by LabVIEW makes the construction of a Web server easier than other languages and is compatible with other application programs. An optical current sensor was composed using a 1310 [nm] laser diode, and 9/125 [${\mu}m$] standard single mode optical fiber and was created to be a close type sensor. Data measurement using Web servers has the advantage of monitoring electric power systems at a great distance and can fuse IT technology and electric power systems. Also, this measurement uses inexpensive mounting and programming when compared to existing measurement equipment allowing the construction of a measurement system in any situation or surrounding.

Epoxidized soybean oil(ESO)의 합성 및 4 관능성 에폭시 수지/ESO 블렌드 시스템의 물성 (Synthesis of Epoxidized Soybean Oil (ESO) and its Blends with Tetrafunctional Epoxy Resins)

  • Lee, Jae-Rock;Jin, Fan-Long;Park, Soo-Jin
    • 한국복합재료학회:학술대회논문집
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    • 한국복합재료학회 2003년도 춘계학술발표대회 논문집
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    • pp.180-183
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    • 2003
  • In this work. a potential inexpensive epoxy resin. epoxidized soybean oil (ESO) was synthesized and applied as a toughening agent for 4.4'-tetradiglycidyl diaminodiphenyl methane (TGDDM). The chemical structure of ESO was characterized by FT-IR, $^1H NMR, and ^{13}C NMR$ spectroscopy. The curing behaviors. thermal stabilities. fracture toughness. and flexural strength of TGDDM/ESO blend systems were investigated by using the dynamic DSC. thermogravimetric analysis (TGA). and flexural tests. The thermal stabilities of TGDDM/ESO blend systems were decreased with increasing ESO contents. whereas the critical stress intensity factor ($K_{IC}$) and flexural strength ($\sigma_f$) were increased with ESO contents up to 10 wt% ESO.

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열대류형 초소형 가속도계의 최적 설계 (Optimal Design of a Convective MEMS Accelerometer)

  • 박병규;김준원;문일권;김동식
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2008년도 추계학술대회A
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    • pp.1951-1956
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    • 2008
  • Various MEMS accelerometers are used in engineering applications including automobiles, mobile phones, military systems, and electronic devices. Among them, the thermal accelerometer employing the temperature difference induced by the convective flow inside the micro cavity has been a topic of interest. As the convective sensor does not utilize a solid proof mass, it is compact, lightweight, inexpensive to manufacture, sensitive and highly endurable to mechanical shock. However, the complexity of the convective flow and various design constraints make optimization of a device a crucial step before fabrication. In this work, optimization of a 2-axis thermal convective MEMS accelerometer is conducted based on 3-dimensional numerical simulation. Parametric studies are performed by varying the several design variables such as the heater shape/size, the cavity size and types of the gas medium and the position of temperature probes in the sensor. The results of optimal design are presented.

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세균성 폐렴과 항생제 선택 (Antibiotics for bacterial pneumonia in children)

  • 염혜영
    • Clinical and Experimental Pediatrics
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    • 제52권3호
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    • pp.283-288
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    • 2009
  • Pneumonia remains the leading cause of mortality in children. Diagnosis depends on a combination of factors, including clinical assessment, radiological and laboratory findings. Although Streptococcus pneumoniae remains the most important cause of childhood bacterial pneumonia, the great majority of cases of community-acquired pneumonia (CAP) are of viral etiology. A new, rapid, and inexpensive test that differentiates viral from bacterial pneumonia is needed to decide empiric antibiotic treatment. Antibiotics effective against the expected bacterial pathogens should be instituted where necessary. The role of emerging pathogens and the effect of pneumococcal resistance and heptavalent conjugate pneumococcal vaccines are to be considered in practice. There are reports supporting the valid and highly efficacious use of penicillin as a first-line drug for treating CAP. This review raises the issue of the overuse of unnecessary antibiotics in viral CAPs and the use of second or third-line antibiotics for non-complicated pneumonias in most clinical settings.

국제전자상거래시대(國際電子商去來時代)를 대비(對備)한 BOLERO Project와 TradeCard System (The Comparison of BOLERO project and TradeCard syetem as Settlement Method in International Trade)

  • 안병수
    • 무역상무연구
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    • 제13권
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    • pp.933-977
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    • 2000
  • BOLERO project and TradeCard System are attracted public attention as new settlement method that is able to substitute for documentary letter of credit. BOLERO is the business processes and methods, together with the digital information system, which are provided by Bolero International for communicating Messages and Documents and facilitating business transactions. TradeCard aim to make international business-to-business e-Commerce easy, fast, inexpensive and secure while innovating current documentary compliance and financial settlement mechanisms. The main purpose of this paper is to search the possibility of paperless trade. Since, this paper examine the international legal feasibility of these systems and compare the strength and weakness.

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A Framework for ASP service

  • Go, Cheol-Young;Sohn, Joo-Chan;Baik, Jong-Myeong
    • 한국전자거래학회:학술대회논문집
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    • 한국전자거래학회 2001년도 International Conference CALS/EC KOREA
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    • pp.477-482
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    • 2001
  • Under rapidly changing business surrounding, companies need information systems to keep their competitive powers and forecast business surroundings beforehand. In these trends, interests of ASP (Application Service Provider) service is increasing because of the advantage for efficiency to maintain a system and an inexpensive investment to build a system, and this service is rapidly spreading to many parts from simple functions to ERP system. In this research, we argue about these problems and about administrative framework technology for efficient ASP service of ERP system.

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선박용 광섬유 자이로콤파스의 제작에 관한 연구 (A Study on the Fabrication of a Fiber Optic Gyrocompass for Ships)

  • 이석정;배정철;홍창희
    • 한국항해항만학회:학술대회논문집
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    • 한국항해항만학회 1998년도 춘계학술발표회 논문집
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    • pp.56-63
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    • 1998
  • A fiber optic gyrocompass for ships was made in consideratino of cost, reliability and convenience. In order to reduce the cost a cheaper fiber sensor was used inthis system. The accuracy was increased by replacing a 180ppr-slit disk with a 1000ppr-encoder. The reliability was also increased by improving the signal processing electronics. This system was made as a heading angle display type for convenience. Although more inexpensive FOG than that of the previous system was used , the accuracy of this compass was increased about 0.5$^{\circ}$. Moreover, it has a very fast warm-up time of about 5minutes. Therefore, this compass can show the prospect of proactical use on ships if it is installed ona stabilizer against the dynamic motion such as rolling and pitching.

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외상성 뇌손상환자에서 Amantadine의 사용 (The use of Amantadine in Traumatic Brain Injury Patients)

  • 정한용;김양래
    • 생물정신의학
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    • 제7권1호
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    • pp.55-63
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    • 2000
  • Avariety of symptoms can occur following traumatic brain injury(TBI) or other types of acquired brain injury. These symptoms can include problems with short-term memory, attention, planning, problem solving, impulsivity, disinhibition, poor motivation, and other behavioral and cognitive deficit. These symptoms may respond to certain drugs, such as dopaminergic agents. Amantadine may protect patients from secondary neuronal damage after brain injury as a effect of NMDA receptor antagonists and may improve functioning of brain-injured patients as a dopaminergic agonist. Clinically, based on current evidence, amantadine may provide a potentially effective, safe, and inexpensive option for treating the cognitive, mood, and behavioral disorders of individuals with brain injury. The rationales for using amantadine are discussed, and pertinent literatures are reviewed.

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