• 소음진동
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• 제5권4호
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• pp.543-553
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• 1995

Modern steam turbine generators are being built as a higher power and larger system, experiencing more frequent starts and stops of operation due to a constant change of power demands. Hence, they are inevitably more vulnerable to various vibrations, and more often exposed to the danger of sudden vibration accidents than ever before. Even under the circumstances, in order to secure the system reliability of steampower plants and there by to supply safely the public electricity, it is important to prevent a sudden vibration accident in one hand and even when it happens, to raise an operating efficiency of the plants throught swift and precise treatments in the other. In this study, an interactive vibration diagnostic system has been developed to make the on-site vibration diagnosis of steam turbine generators possible and convenient, utilizing a note-book PC. For this purpose, at first the principal vibration phenomena, such as various unbalance and unstable vibrations as well as rubbing, misalignment, and shaft crack vibrations, have been systematically classified as grouped parameters of vibration frequencies, amplitudes, phases, rotating speeds at the time of accident, and operating conditions or condition changes. A new complex vibration diagnostic table has been constructed from the causal relations between the characteristic parameters and the principal vibration phenomena. Then, the diagnostic system has been developed to screen and issue the corresponding vibration phenomena by assigning to each user-selected combination of characteristic parameters a unique characteristic vector and comparing this vector with a diagnostic vector of each vibration phenomenon based on the constructed diagnostic table. Moreover, the diagnostic system has a logic whose diagnosis may be performed successfully by inputing only some of the corresponding characteristic parameters without having to input all the parameters. The developed diagnostic system has been applied to perform the diagnosis of several real cases of steam turbine vibration accidents. And the results have been quite satisfactory.

• Journal of Acupuncture Research
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• 제23권3호
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• pp.231-239
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• 2006

Functional medicine is a system which utilizes certain investigative and treatment methods that are primarily oriented toward the recognition of functional disorder. Functional disorders take place on an energetic plane. This plane is not capturable using our regular investigatory techniques, such as X -ray. ultrasound, computer tomography and laboratory analyses. The 7-zone-diagnostic system(VEGA-DFM 722 and ABR-2000, etc) is a diagnostic device Which applies pulse signals to predetermined bodily locations. Applying alternating positive and negative stress to tissues with positive and negative pulses first manifests itself as negative and positive wave forms. The skin has many functions as an organ. It is the organism's interlace with the outsider world. Hence, the manner in which the skin reacts to external stimuli reflects the current state of the organism(as meridian systems). This system make a diagnosis of functional disorder or some typical organic diseases include stress of the mind or the body, and the energetic situation, reserves. We are known a disorder or disease throw the result chart. This result chart contain disorder flow wave forms and some valuable diagnostic hints (letters ; S, OM, RA, etc). In spite of this 7-zone-diagnostic system that is applied plentifully in the clinical application, there is not a statistics which is suitable. Therefor we must carry out many various research in the future.

• 대한상한금궤의학회지
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• 제8권1호
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• pp.67-85
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• 2016

Objectives: In this paper, two cases which showed the meaningful results on the patients' chief complaints were analyzed. The patients were treated with the Mahwang-Haengin-Gamcho-seokgo-tang herbal medication based on Shanghanlun disease pattern identification diagnostic system. Methods: The patients were diagnosed based on Shanghanlun, disease pattern identification diagnostic system. In case 1, the change of menstruation cycle was noted and pre-menstrual discomforts were measured with Menstrual Distress Questionnaire(MDQ). In case 2, Quality of life questionnaire for adult Korean asthmatics (QLQAKA) was used to estimate the quality of the patient's life. Results: All the symptoms were improved after the Mahwang-Haengin-Gamcho-seokgotang treatment. In case 1, the menstruation cycle decreased to 30 days average. MDQ score decreased 143 to 103. In case 2, the change of the QLQAKA score as 1.647 average point is considered as a meaningful improvement. Conclusion: With great difference to a 'Symptom-Medicine' diagnostic system, the disease pattern identification diagnostic system seeks the pathologic pattern through the patient's whole life. More studies and multiple cases based on the diagnostic system are needed to prove this possibility later.

• 컴퓨터교육학회논문지
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• 제6권3호
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• pp.197-205
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• 2003

효과적인 교수활동을 위해서는 교수자가 학습자의 현 수준을 정확히 파악해야 한다. 학습자의 수준 파악을 위해서는 일반적으로 진단평가를 활용한다. 그러나 시간상의 제약으로 인해 교수자가 필요로 하는 모든 경우에 학습자의 수준 파악을 위한 진단평가를 실시하기는 어렵다. 이에 본 논문에서는 교수자 교수방법의 효율화를 위한 웹 기반 진단평가시스템을 제안한다. 제안하는 시스템에서는 교수자가 웹을 통해 원하는 평가문제를 수시로 입력하는 것이 가능하며 학습자는 자신의 수강과목의 일정에 따라 시공간 제약 없이 개별적으로 온라인 진단평가를 수행할 수 있다. 또한 제안하는 시스템에서는 각 학습자의 평가결과를 자동으로 처리하여 교수자가 학습자의 현재 수준을 분석하고 교육 수준을 결정할 수 있는 다양한 통계 자료를 제시해준다.

• 대한핵의학회지
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• 제8권1_2호
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• pp.39-47
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• 1974

The purpose of this study is to evalute the diagnostic value of the brain scanning and compare the diagnostic accuracy between the scan and carotid angiography. 109 cases which are proved by specific method to each disease, are analized to evalute the diagnostic value of the brain scanning. The 70 cases among the proven 109 case are performed both the scanning and the arteriography and analized to compare the accuracy between the scanning and the arteriography. The results are as follows; 1. The diagnostic accuracy of the brain scanning in the diseases of the central nervous system is 64.2%. 2. The diagnostic accuracy of the brain scanning in the brain tumor is 88%, especially brain abscess. glioma, glioblastoma multiforme, menirgioma and metastic tumor show high positive rate. 3. The diagnostic accuracy in the disease of the brain vessels is 54 %. 4. The comparison of the diagnostic value between the scanning and the arteriography is as follows; 1) The diagnostic value in all diseases of the central nervous system is nearly equal. 2) The diagnostic accuracy in the intracranial tumor is slightly higher in the brain scanning (90.9%) than in the arteriography (81.8%). 3) The diagnostic accuracy in the disease of the brain vessel is higher in the arteriography (77.3%) than in the scanning (54.5%). 5) The diagnostic value when combining the scanning and the arteriography, is 83% in the all central nervous system-lesions, 97% in the cranial tumor and 81.8% in the disease of the central nervous system-vessel. The brain scanning is simple and safe procedure, and moreover has excellent diagnostic value in the diagnosis of the central nervous system lesion.

• Tribology and Lubricants
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• 제17권2호
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• pp.153-161
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• 2001

The development of techniques in diagnosing the state of the system is one of the essential tools in establishing the automation and unmanned manufacturing system for the realization of CIM/FMS in the fields. In this paper, we developed various diagnostic schemes for the journal bearing supported rotor system. Up to now, vibration of the shaft, measurement of the displacement and the temperature have been used for diagnostic tools, however, the statistical features only could not differentiate the state from states. Thus, we identified the sensor data f3r the steady state in the signal processing and then applied the fuzzy c-mean technology to cope with the nonlinear characteristics of the system. This will, in return, establish a possible diagnostic system for the rotor system in the fields.

• 한국임상수의학회지
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• 제40권6호
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• pp.429-437
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• 2023

In veterinary medicine, most radiographic images are obtained by restraining patients, inevitably exposing the restrainer to secondary scattered radiation. Radiation exposure can result in stochastic reactions such as cancer and genetic effects, as well as deterministic reactions such as skin burns, cataracts, and bone marrow suppression. Radiation-shielding equipment, including aprons, thyroid shields, eyewear, and gloves, can reduce radiation exposure. However, the risk of radiation exposure to the upper arms, face, and back remains, and lead aprons and thyroid shields are heavy, restricting movement. We designed a new radiation-shielding system and compared its shielding ability with those of conventional radiation-shielding systems. We hypothesized that the new shielding system would have a wider radiation-shielding range and similar shielding ability. The radiation exposure dose differed significantly between the conventional and new shielding systems in the forehead, chin, and bilateral upper arm areas (p < 0.001). When both systems were used together, the radiation-shielding ability was better than when only one system was used at all anatomical locations (p < 0.01). This study suggests that the new radiation-shielding system is essential and convenient for veterinary radiation workers because it is a step closer to radiation safety in veterinary radiography.

• 정보처리학회논문지A
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• 제16A권6호
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• pp.481-488
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• 2009

가스절연개폐장치(Gas Insulated Switchgear:GIS)는 SF6가스를 절연 매체로 하는 대용량 전력 차단기기이다. GIS는 단순한 구조로 고장이 적고 신뢰성이 높은 편이지만 내부를 볼 수 없어 고장 확인이 어렵고 고장이 발생하면 파급 효과가 크고 복구가 어렵다. 따라서 GIS 내부의 이상 징후를 초기에 찾아낼 수 있도록 GIS 예방진단시스템이 도입되었다. GIS 예방진단시스템은 센서에서 수집, 분석한 정보로 이상 징후를 판 단하기 때문에 데이터의 신뢰성과 적시성이 중요하다. 하지만 기존 시스템은 중앙 집중 데이터 수집 방식으로 효율이 낮고 신뢰성과 적시성의 보장이 어렵다. 이러한 신뢰성과 적시성을 보장하기 위하여 GIS 예방진단시스템은 실시간성을 보장하는 미들웨어를 탑재해야 한다. 따라서 본 논문에서는 GIS 예방진단시스템의 신뢰성 향상을 위하여 실시간 분산 컴퓨팅의 적시성 보장을 위해 제안된 TMO를 적용한 미들웨어를 사용한 다. 그리고 TMO를 적용한 데이터 수집 및 감시, 제어 방법을 적용한 새로운 GIS 예방진단 시스템을 제안한다. 논문에서 제안하는 시스템은 TMO의 실시간 기능을 활용하여 데이터의 분산 처리가 가능한 통신제어장치를 개발하여 사용한다. 통신제어장치는 TMO를 통해 실시간 데이 터 수집 및 처리 과정의 적시성을 보장하고 데이터의 신뢰성을 높여 시스템의 성능 향상에 기여한다. 또한, 기존의 서버의 데이터 수집 및 처 리 과정을 통신제어장치가 부담하여 서버의 부하를 줄이고 향후 분산 환경을 지원할 수 있도록 설계하였다. 따라서 제안하는 시스템은 통신제 어장치의 적시성 보장을 통해 GIS 예방진단시스템의 신뢰성과 성능을 향상시키고 GIS의 안정적인 운영을 보장할 수 있다.

• 전자공학회논문지B
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• 제32B권12호
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• pp.1687-1696
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• 1995

An integrated fault diagnosis system for heterogeneous manufacturing environments is developed. This system has a contrast with existing diagnosis systems in the respect that they are mostly for diagnosing faults on individual machines. In addition to the usual (e.g., audio, electrical) diagnostic signals, the characteristics of products from the machines are considered as the unifying diagnostic parameters among heterogeneous machines in the diagnosis. The system is composed of a knowledge representation scheme and a diagnostic query processing mechanism. Its knowledge representation scheme allows the diagnostic knowledges from heterogeneous unit diagnostic systems to be uniformly expressed in terms of the causal relations among relevant data items. It is flexible in the sense that causes for one relation can be effects for another may be reflected on our knowledge representation scheme. The diagnosis mechanism is based on a probabilistic inferencing method. This probablistic diagnosis mechanism provides more general diagnosis than existing ones in that it accommodates multiple causes and takes complication among causes into account. These scheme and mechanism are applied to a typical example to demonstrate how our system works.

• 한국정밀공학회지
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• 제13권10호
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• pp.112-122
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• 1996

In order to monitior machine tool condition and diagnose alarm states due to electrical and mechanical faults, and expert system using diagnostic parameters of NC machine tools was developed. A model-based knowledge base was constructed via searching and comparing procedures of diagnostic parameters and state parameters of the machine tool. Diagnostic monitoring results generate through a successive type inference engine were graphically displayed on the screen of the console. The validity and reliability of the expert system was rcrified on a vertical machining center equipped with FANUC OMC through a series of experiments.