• BMB Reports
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• 제47권9호
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• pp.475-482
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• 2014

Ubiquitin (Ub) is a versatile signaling molecule that plays important roles in a variety of cellular processes. Cellular Ub pools, which are composed of free Ub and Ub conjugates, are in dynamic equilibrium inside cells. In particular, increasing evidence suggests that Ub homeostasis, or the maintenance of free Ub above certain threshold levels, is important for cellular function and survival under normal or stress conditions. Accurate determination of various Ub species, including levels of free Ub and specific Ub chain linkages, have become possible in biological specimens as a result of the introduction of the proteomic approach using mass spectrometry. This technology has facilitated research on dynamic properties of cellular Ub pools and has provided tools for in-depth investigation of Ub homeostasis. In this review, we have also discussed the consequences of the disruption of Ub pool dynamics and homeostasis via deletion of polyubiquitin genes or mutations of deubiquitinating enzymes. The common consequence was a reduced availability of free Ub and a significant impact on the function and viability of cells. These observations further indicate that the levels of free Ub are important determinants for cellular protection.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제49권6호
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• pp.354-359
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• 2023

The temporomandibular joint is a unique structure composed of the joint capsule, articular disc, mandibular condyles, glenoid fossa of the temporal bone, surrounding ligaments, and associated muscles. The condyle is one of the major components of a functional temporomandibular joint. Reconstruction of large mandibular defects involving the condyle is a surgical challenge for oral and maxillofacial surgeons. To restore large mandibular defects, there are different options for free flap method such as fibula, scapula, and iliac crest. Currently, the vascularized fibula free flap is the gold standard for reconstruction of complex mandibular defects involving the condyle. In the present report, neocondyle regeneration after mandible reconstruction including the condyle head with fibula free flap was evaluated. In this report, two patients were evaluated periodically, and remodeling of the distal end of the free fibula was observed in both cases after condylectomy or mandibulectomy. With preservation of the articular disc, trapezoidal shaping of the neocondyle, and elastic guidance of occlusion, neocondyle bone regeneration occured without ankylosis. Preservation of the articular disc and maintenance of proper occlusion are critical factors in regeneration of the neocondyle after mandible reconstruction.

• 대한생식의학회:학술대회논문집
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• 대한불임학회 2001년도 제41차 추계학술대회
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• pp.103-103
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• 2001

• 대한생식의학회:학술대회논문집
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• 대한불임학회 2002년도 제42차 춘계학술대회
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• pp.88-89
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• 2002

• 한국철도학회:학술대회논문집
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• 한국철도학회 2002년도 춘계학술대회 논문집
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• pp.213-218
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• 2002

A new German high speed railway slab track was investigated. The construction objective was to provide a durable and maintenance free track system consisting of precast concretepanels of consistently high quality and highest achievable accuracy in track geometry. The System on the basis of precast panels similar to the slab track system constructed on the line Dachau- Karlsfeld in 1997.

• Structural Monitoring and Maintenance
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• 제5권2호
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• pp.273-295
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• 2018

In this study, an investigation of a damage detection methodology for global condition assessment is presented. A particular emphasis is put on the utilization of wireless sensors for more practical, less time consuming, less expensive and safer monitoring and eventually maintenance purposes. Wireless sensors are deployed with a sensor roving technique to maintain a dense sensor field yet requiring fewer sensors. The time series analysis method called ARX models (Auto-Regressive models with eXogeneous input) for different sensor clusters is implemented for the exploration of artificially induced damage and their locations. The performance of the technique is verified by making use of the data sets acquired from a 4-span bridge-type steel structure in a controlled laboratory environment. In that, the free response vibration data of the structure for a specific sensor cluster is measured by both wired and wireless sensors and the acceleration output of each sensor is used as an input to ARX model to estimate the response of the reference channel of that cluster. Using both data types, the ARX based time series analysis method is shown to be effective for damage detection and localization along with the interpretations and conclusions.

• 산업경영시스템학회지
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• 제30권1호
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• pp.25-32
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• 2007

Automobile manufacturing companies should provide the products and service that can satisfy consumers who usually want various kinds of automobiles. This paper studied the relations among several demographic characteristics(gender, age, occupation, income) of consumers and automobile's attributes(engine performance, engine displacement, price, maintenance expenses, color, etc.) and preferred automobile(kind, size, company, price). For the relation research we established a model and related hypotheses and used a questionnaire survey, where 350 subjects were questioned. After the analysis, many statistically significant results are obtained : consumer's gender has relations with the preference for engine performance, engine displacement, price, color, and design; age has relations with the preference for engine displacement, maintenance expenses, free checking during A/S period, etc., occupation has relations with the preference for engine performance, engine displacement, price, maintenance expenses, fuel efficiency, etc. : income has relations with the preference for engine performance, engine displacement, price, maintenance expenses, mileage, reputation of car manufacturing companies, etc.; price and fuel efficiency has relations with the preference for car manufacturing companies. These results suggest the consumer-oriented sales of automobiles and are expected to be helpful for the effective strategy development of automobile marketing.

• 국제학술발표논문집
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• The 10th International Conference on Construction Engineering and Project Management
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• pp.949-956
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• 2024

While Building Information Modeling (BIM) is an important tool for digitization in the architecture industry, its introduction rate in the field of facility maintenance and management is still low. Accordingly, this study aims to spread BIM to this field. The introduction of BIM enables centralization of facility data that has been managed separately in two-dimensional data and allows analysis across data in three-dimensional space. This study includes three phases. Phase 1 is to create a BIM model of the head office building in Japan as an example, phase 2 is to link the BIM model with the building data, and phase 3 is to create an analysis environment based on the data-linked BIM created. The BIM model is linked to three sheets of data using Dynamo; data showing the seating ratio of the seats in the free-address office owned by the facility, the amount of electricity used, and the repair work history of the building. Finally, an analysis environment is created for using the BIM model with data linkage in actual facility maintenance and management operations. As the platform created in this study now makes it possible to analyze multiple sets of data in a three-dimensional environment, it is expected to provide multifaceted solutions through analysis across multiple datasets.

• 한국항행학회논문지
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• 제15권4호
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• pp.502-509
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• 2011

GPS 반송파를 이용한 정밀 항법 수행 시 미지 정수 결정이 필수적이다. 한번 결정된 미지 정수는 사이클 슬립이 발생하지 않는 한 변하지 않는다. 그러나 전파 관측 환경의 변화에 따라 사이클 슬립이 발생하게 되며, 이러한 상황에서 연속적인 항법 정보 제공을 위한 적절한 대응 조치를 취해 주어야 한다. 그러나 이러한 조치들은 매우 번거로우며, 소프트웨어적인 복잡성을 야기 한다는 문제가 있다. 본 논문에서는 미지 정수 유지 및 재검색 과정을 단순화하기 위해 시스템 운동 모델을 이용하여 사이클 슬립에 무관한 위치 제공 기법을 제안하였다. 제안된 방법은 고의적으로 사이클 슬립을 발생시켜 대응 성능을 확인하였으며, 이 결과 사이클 슬립과 무관하게 항법 정보를 제공할 수 있음을 확인하였다.

• Structural Monitoring and Maintenance
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• 제10권4호
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• pp.361-379
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• 2023

In cable structure maintenance, particularly for cable-stayed bridges, cable safety assessment relies on estimating cable tension. Conventionally, in Japan, cable tension is estimated from the natural frequencies of the cable using the higher-order vibration method. In recent years, dampers have been installed on cables to reduce cable vibrations. Because the higher-order vibration method is a method for damper-free cables, the damper must be removed to measure the natural frequencies of a cable without a damper. However, cables on some cable-stayed bridges have two dampers: one on the girder side and another on the tower side. Notably, removing and reinstalling the damper on the tower side are considerably more time- and labor-intensive. This paper introduces a tension estimation method for cables with two dampers, using natural frequencies. The proposed method was validated through numerical simulation and experiment. In the numerical tests, without measurement error in the natural frequencies, the maximum estimation error among 100 models was 3.3%. With measurement error of 2%, the average estimation error was within 5%, with a maximum error of 9%. The proposed method has high accuracy because the higher-order vibration method for a damper-free cable still has an estimation error of 5%. The experimental verification emphasizes the importance of accurate damper modeling, highlighting potential discrepancies between existing damper design formula and actual damper behavior. By revising the damper formula, the proposed method achieved accurate cable tension estimation, with a maximum estimation error of approximately 10%.