• Journal of the Korean Society of Propulsion Engineers
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• v.16 no.4
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• pp.23-32
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• 2012

The present study is aimed to develop an integrated performance analysis approach for the application of a compressor with variable inlet guide vane (VIGV) and vairable stator vane (VSV) in a small turbofan engine. For the integrated analysis approach, an engine performance analysis program, NPSS and a computer program used for predicting of axial flow compressor performance based on stage stacking method, STGSTK were linked with an optimisation package, Isight. This enables off-design performance analysis for the turbofan engine with VIGV and VSV hence provides the capability to predict stable operation condition of the engine with acceptable surge margin.

• Journal of Korea Multimedia Society
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• v.21 no.12
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• pp.1396-1406
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• 2018

Lane detection is a key function in developing autonomous vehicle technology. In this paper, we propose a lane marker detection algorithm robust to environmental variation targeting low cost embedded computing devices. The proposed algorithm consists of two phases: initialization phase which is slow but has relatively higher accuracy; and the tracking phase which is fast and has the reliable performance in a limited condition. The initialization phase detects lane markers using a set of filters utilizing the various features of lane markers. The tracking phase uses Kalman filter to accelerate the lane marker detection processing. In a tracking phase, we measure the reliability of the detection results and switch it to initialization phase if the confidence level becomes below a threshold. By combining the initialization and tracking phases we achieved high accuracy and acceptable computing speed even under a low cost computing resources in which we cannot use the computing intensive algorithm such as deep learning approach. Experimental results show that the detection accuracy is about 95% on average and the processing speed is about 20 frames per second with Raspberry Pi 3 which is low cost device.

• Smart Structures and Systems
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• v.24 no.5
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• pp.617-630
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• 2019

Currently most of the vision-based structural identification research focus either on structural input (vehicle location) estimation or on structural output (structural displacement and strain responses) estimation. The structural condition assessment at global level just with the vision-based structural output cannot give a normalized response irrespective of the type and/or load configurations of the vehicles. Combining the vision-based structural input and the structural output from non-contact sensors overcomes the disadvantage given above, while reducing cost, time, labor force including cable wiring work. In conventional traffic monitoring, sometimes traffic closure is essential for bridge structures, which may cause other severe problems such as traffic jams and accidents. In this study, a completely non-contact structural identification system is proposed, and the system mainly targets the identification of bridge unit influence line (UIL) under operational traffic. Both the structural input (vehicle location information) and output (displacement responses) are obtained by only using cameras and computer vision techniques. Multiple cameras are synchronized by audio signal pattern recognition. The proposed system is verified with a laboratory experiment on a scaled bridge model under a small moving truck load and a field application on a footbridge on campus under a moving golf cart load. The UILs are successfully identified in both bridge cases. The pedestrian loads are also estimated with the extracted UIL and the predicted weights of pedestrians are observed to be in acceptable ranges.

• Structural Engineering and Mechanics
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• v.83 no.4
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• pp.451-463
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• 2022

The present study deals with forced vibrations of an elastic circular plate supported along its circular edge by unilateral elastic springs. The plate is assumed to be subjected to a uniformly distributed and a concentrated load. Under the combination of these loads, equations of motion are explicitly derived for static and dynamic response analyses by assuming a series of the displacement functions of time and other unknown parameters which are to be determined by employing Lagrangian functional. The approximate solution is sought by applying the Lagrange equations of motions by using the potential energy of the external forces that includes the contributions of the edge forces and the external moments, i.e., those of the effects of the boundary condition to the analysis. For the numerical treatment of the problem in the time domain, the linear acceleration procedure is adopted. The tensionless character of the support is taken into account by using an iterative process and, the coordinate functions for the displacement field are selected to partially fulfill the boundary conditions so that an acceptable approximation can be achieved faster. Numerical results are presented in the figures focusing on the nonlinearity of the problem due to the plate lift-off from the unilateral springs at the edge support.

• Journal of Dairy Science and Biotechnology
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• v.41 no.1
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• pp.1-8
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• 2023

Response surface methodology (RSM) is a statistical approach widely used in food processing to optimize the formulation, processing conditions, and quality of food products. The homogenization process is achieved by subjecting milk to high pressure, which breaks down fat globules and disperses fat more evenly throughout milk. This study focuses on an application of RSM including the logit transformation to predict the efficiency of milk homogenization, which can be maximized by minimizing the relative difference in fat percentage between the top part and the remainder of milk. To avoid a negative predicted value of the minimum of this proportion, the logit transformation is used to turn the proportion into the logit, whose possible values are real numbers. Then, the logit values are modeled and optimized. Subsequently, the logistic transformation is used to turn the predicted logit into the predicted proportion. From our model, the optimum condition for the maximized efficiency of milk homogenization was predicted as the combination of a homogenizer pressure of 30 MPa, a storage temperature of 10℃, and a storage period of 10 days. Additionally, with a combination of a homogenizer pressure of 30 MPa, a storage temperature of 10℃, and a storage period of 50 days, the level of milk homogenization was predicted to be acceptable, even with the problem of extrapolation taken into account.

• Advances in concrete construction
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• v.15 no.1
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• pp.41-46
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• 2023

Sport has no age limit and can be done anywhere and in any condition with minimal equipment. The existence of sports spaces in all parts of the world is considered a citizen's right. One of the activities carried out in this field is installing sports equipment and structures in parks and encouraging citizens to use this equipment for physical health with the least cost and facilities. Installing sports structures in open spaces such as parks is a practical step for developing citizens' sports. Although using devices in parks is acceptable, it is more critical to meet scientific and technical standards. The components of these structures must have high strength and endurance against changes in environmental conditions such as humidity, temperature difference, and corrosion. Among the various causes of material degradation, corrosion has always been one of several fundamental causes of metal equipment failure. Sports structures in open spaces are not safe from corrosion. Uniform corrosion is the most common type of corrosion. This corrosion usually occurs uniformly through a chemical or electrochemical reaction across the surface exposed to the corrosive environment. Rust and corrosion of outdoor sports structures are examples of this corrosion. For this reason, in this research, with the green synthesis of silica nanoparticles and its application in outdoor sports structures, the life span of these structures can be increased for the use of physical exercises as well as their quality.

• International conference on construction engineering and project management
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• 2017.10a
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• pp.201-209
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• 2017

Facade structure system plays an important role in modern architecture and design. Many contractors start using Building Information Modeling (BIM) to help design and lay-out façade walls in recent years. However, there are still some users refuse to accept BIM on façade construction. Therefore, we employed Technology Acceptance Model (TAM) to assess the users acceptable of BIM work flow, with using a practical case of facade construction in Chongqing Wanda City. The factors that will affect the builder's decision of whether using BIM or not when construct façade, and the relationship among them will be found via this model. Through the analysis using TAM, this research found that the direct factors influencing the completely acceptance of BIM in façade construction is the BIM quality and Result Demonstrating, and the parameter impacting the intuition engendering is the Exterior Condition. Therefore, this paper proposes a more systemic model of BIM acceptance in curtain wall to analyze the user's acceptance. The solution can also offer a reference for future research and construct on façade structure. The acceptance model has the significance that it can help to analyze the reason why users refuse to use BIM in façade construction, thus to help users accept BIM.

• Clinics in Shoulder and Elbow
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• v.26 no.3
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• pp.312-322
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• 2023

Background: Silicone radial head prostheses (SRHP) are considered obsolete due to reports of frequent failure and destructive silicone-induced synovitis. Considering the good outcomes of modern non-radial silicone joint implants, the extent of scientific evidence for this negative view is unclear. The aim of this research was to systematically analyze the clinical evidence on complications and outcomes of SRHP and how SRHP compare to both non-SRHP and silicone prostheses of other joints. Methods: A systematic literature review was conducted through the Cochrane, PubMed, and Embase databases. Results: Eight cohort studies were included, consisting of 142 patients and follow-up periods ranging from 23 months to 8 years. Average patient satisfaction was 86%, range of 71%-100%, and 58 complications were seen, but no cases of synovitis. These outcomes were in line with non-SRHP. Four case series with 11 cases of synovitis were found, all due to implant fractures years to decades after implantation. Six systematic reviews of currently used non-radial silicone joint implants showed excellent outcomes with low complication rates. Conclusions: Since SRHP have satisfactory clinical results and an acceptable complication rate when selecting a patient group in suitable condition for surgical indications, it is considered that SRHP can still be chosen as a potential surgical treatment method in current clinical practice.

• Archives of design research
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• v.13 no.3
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• pp.221-234
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• 2000

This thesis aims to study the space concept of the constructive mode in the work space of the postmodernism artists since 1970s. According to the changing view of the world artists, they are searching for the characteristics of having the parameter of formative organization on how they are related to the constructive system which represents the work styles. First, this study searches for the theoretical approaches of the constructive system and parameters that were studied by Le Corbusier - the module concept as the meaning of order system being used for the basic formative construction Second, when it is regarded as a formative construction in making art as the'principles of organization'(the law of living form), which was defined by Suzanne Langer in the formative theory as the organized structure shown in growth structure in mu and ecological system, the principles governing the module rules were arthmetically analysed art-work space through the dynamic symmetry of Jay Hambidge. Therefore, this study shows the principles working on the parameters for new formative organization as follows: First, the module in the work space should be designed and built from the dynamic symmetry. Second, the module should satisfy the human needs that it must be acceptable, efficient, flexible, which are the necessary and sufficient condition for the dynamic symmetry. Third, the dynamic symmetry which has the principle of Reciprocity and the principle of Complement as its primary construction principle has the common properties and the reciprocity in the construction of the work space and when it has the self similarity, it segments organically the total space without damaging the continuum.

• Journal of Embryo Transfer
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• v.28 no.1
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• pp.31-39
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• 2013

Alpha-tocopherol as an antioxidant acts in preservation of chilled semen by preserving cell membrane damage from lipid peroxidation. Optimum concentrations of ${\alpha}$-tocopherol in egg yolk-citrate (EYC) extender need to be studied in crossbred bull's semen. Different concentrations of ${\alpha}$-tocopherol viz. 0, 1, 2, 4 and 6mg per ml of extender were used. Semen was collected once a week from four bulls used to regular collection, aged 4 to 7 years, weighing 320 to 450 kg, and with body condition score 4 to 4.5 and scrotal circumference 23 to 32 cm. Semen was evaluated routinely and sperm morphology was viewed under light microscope at ${\times}1,000$ magnification after fixing with buffered formal saline. Over 90% had normal head, acrosome, mid-piece and tail. Semen was diluted with egg-yolk-citrate extender to produce $15{\times}10^6$ spermatozoa/ml and 0, 1, 2, 4 and 6 mg/ml ${\alpha}$-tocopherol were added. The semens amples were kept at $8^{\circ}C$. Sperm motility and viability were examined daily up to 5 days under light microscopy at ${\times}200$ magnification. Sperm viability was acceptable (${\geq}40%$) up to the $4^{th}$ day with all concentrations of ${\alpha}$-tocopherol and up to the $5^{th}$ day with 2 mg/ml ${\alpha}$-tocopherol. Sperm motility was acceptable (${\geq}40%$) up to the $3^{rd}$ day irrespective of ${\alpha}$-tocopherol concentration, and up to the $4^{th}$ day with 2 mg/ml ${\alpha}$-tocopherol. It is suggested that the lifespan of chilled semen may be extended up to 4 days by adding 2mg/ml ${\alpha}$-tocopherol.