• Title/Summary/Keyword: Replacement method

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The Role of Enzyme Replacement Therapy in Fabry Disease in Cardiology Perspective

  • Hongo, Kenichi
    • Journal of mucopolysaccharidosis and rare diseases
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    • v.4 no.1
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    • pp.21-25
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    • 2018
  • Fabry disease is a hereditary lysosomal storage disorder caused by the reduction or absence of lysosomal enzyme alpha-galactosidase A and the accumulation of glycosphingolipids, such as globotriaosylceramide (Gb3), in various organs, including the heart. The prevention of cardiac involvement in Fabry disease can only be achieved by enzyme replacement therapy (ERT), and the method of assessing the efficacy of ERT should be confirmed. Changes in the electrocardiogram, such as the shortening of PQ interval, prolongation of QTc and repolarization abnormalities as well as left ventricular hypertrophy in voltage criteria, can be used to identify Fabry disease patients; however, the usefulness of electrocardiograms for evaluating the efficacy of ERT is limited. The assessment of left ventricular hypertrophy using echocardiography has been established to evaluate the efficacy of ERT during long-term period. A new technique involving speckled tracking method might be useful for detecting early cardiac dysfunction and identifying the effect of ERT for a relatively short period. The estimation of left ventricular hypertrophy using cardiac magnetic resonance (CMR) is also useful for assessing the efficacy of ERT. Identifying late gadolinium enhancement in CMR may affect the effectiveness of ERT, and the new technique of T1 mapping might be useful for monitoring the accumulation of Gb3 during ERT. Histopathology in cardiac biopsy specimens is another potentially useful method for identifying the accumulation of GB3; however, the use of histopathology to evaluate of the efficacy of ERT is limited because of the invasive nature of an endomyocardial biopsy.

Stress Analysis of Femoral Stems on Non-Cemented Total Hip Replacement - A Three-Dimensional Finite Element Analysis -

  • Kim, Sung-Kon;Chae, Soo-Won;Jeong, Jung-Hwan
    • Proceedings of the KOSOMBE Conference
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    • v.1997 no.11
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    • pp.263-266
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    • 1997
  • Three dimensional numerical model based on the finite element method(FEM) were developed to predict the mechanical behavior of hip implants. The purpose of this study is to investigate the stress distribution of two types of cementless total hip replacement femoral component -a straight stem and a curved stem, and to compare their effect on the stress shielding between two types by three dimensional finite element method. The authors analyzed von Mises stress in the cortex & stem and compared the stress between the straight and the curved stem. In comparison of stresses between two different design of femoral stem, there was 25% more decrease of stress in straight stem than curved stem in the medial cortex at proximal region. The straight stem had consistently much lower stresses than the curved stem throughout the whole medial cortex with maximum 70% reduction of stress. However, there was little change in stress between nature and 2 implanted femur throughout the lateral cortex. Stress of femoral stem was much higher in the straight stem than the curved stem up to 60%. The straight stem had more chance of stress shielding and a risk of fatigue fracture of the stem compared with the curved stem in noncement hip arthroplasty. In design of femoral stem still we have to consider to develop design to distribute more even stress on the proximal medial cortex.

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Influence of Iranian low-reactivity GGBFS on the properties of mortars and concretes by Taguchi method

  • Ramezanianpour, A.A.;Kazemian, A.;Radaei, E.;AzariJafari, H.;Moghaddam, M.A.
    • Computers and Concrete
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    • v.13 no.4
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    • pp.423-436
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    • 2014
  • Ground Granulated Blast Furnace Slag (GGBFS) is widely used as an effective partial cement replacement material. GGBFS inclusion has already been proven to improve several performance characteristics of concrete. GGBFS provides enhanced durability, including high resistance to chloride penetration and protection against alkali silica reaction. In this paper results of an experimental research work on influence of low-reactivity GGBFS (which is largely available in Iran) on the properties of mortars and concretes are reported. In the first stage, influence of GGBFS replacement level and fineness on the compressive strength of mortars was investigated using Taguchi method. The analysis of mean (ANOM) statistical approach was also adopted to develop the optimal conditions. Next, based on the obtained results, concrete mixtures were designed and water penetration, capillary absorption, surface resistivity, and compressive strength tests were carried out on highstrength concrete specimens at different ages up to 90 days. The results indicated that 7-day compressive strength is adversely affected by GGBFS inclusion, while the negative effect is less evident at later ages. Also, it was inferred that use of low-reactivity GGBFS (at moderate levels such as 20% and 30%) can enhance the impermeability of high-strength concrete since 28 days age.

Optimization of the Travelling Salesman Problem Using a New Hybrid Genetic Algorithm

  • Zakir Hussain Ahmed;Furat Fahad Altukhaim;Abdul Khader Jilani Saudagar;Shakir Khan
    • International Journal of Computer Science & Network Security
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    • v.24 no.3
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    • pp.12-22
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    • 2024
  • The travelling salesman problem is very famous and very difficult combinatorial optimization problem that has several applications in operations research, computer science and industrial engineering. As the problem is difficult, finding its optimal solution is computationally very difficult. Thus, several researchers have developed heuristic/metaheuristic algorithms for finding heuristic solutions to the problem instances. In this present study, a new hybrid genetic algorithm (HGA) is suggested to find heuristic solution to the problem. In our HGA we used comprehensive sequential constructive crossover, adaptive mutation, 2-opt search and a new local search algorithm along with a replacement method, then executed our HGA on some standard TSPLIB problem instances, and finally, we compared our HGA with simple genetic algorithm and an existing state-of-the-art method. The experimental studies show the effectiveness of our proposed HGA for the problem.

Investigation of the effect of internal curing as a novel method for improvement of post-fire properties of high-performance concrete

  • Moein Mousavi;Habib Akbarzadeh Bengar
    • Computers and Concrete
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    • v.33 no.3
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    • pp.309-324
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    • 2024
  • Internal curing, a widely used method for mitigating early-age shrinkage in concrete, also offers notable advantages for concrete durability. This paper explores the potential of internal curing by partial replacement of sand with fine lightweight aggregate for enhancing the behavior of high-performance concrete at elevated temperatures. Such a technique may prove economical and safe for the construction of skyscrapers, where explosive spalling of high-performance concrete in fire is a potential hazard. To reach this aim, the physico-mechanical features of internally cured high-strength concrete specimens, including mass loss, compressive strength, strain at peak stress, modulus of elasticity, stress-strain curve, toughness, and flexural strength, were investigated under different temperature exposures; and to predict some of these mechanical properties, a number of equations were proposed. Based on the experimental results, an advanced stress-strain model was proposed for internally cured high-performance concrete at different temperature levels, the results of which agreed well with the test data. It was observed that the replacement of 10% of sand with pre-wetted fine lightweight expanded clay aggregate (LECA) not only did not reduce the compressive strength at ambient temperature, but also prevented explosive spalling and could retain 20% of its ambient compressive strength after heating up to 800℃. It was then concluded that internal curing is an excellent method to enhance the performance of high-strength concrete at elevated temperatures.

Data allocation and Replacement Method based on The Access Frequency for Improving The Performance of SSD (SSD의 성능향상을 위한 접근빈도에 따른 데이터 할당 및 교체기법)

  • Yang, Yu-Seok;Kim, Deok-Hwan
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.48 no.5
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    • pp.74-82
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    • 2011
  • SSD has a limitation of number of erase/write cycles and does not allow in-place update unlike the hard disk because SSD is composed of an array of NAND flash memory. Thus, FTL is used to effectively manage SSD of having different characteristics from traditional disk. FTL has page, block, log-block mapping method. Among then, when log-block mapping method such as BAST and FAST is used, the performance of SSD is degraded because frequent merge operations cause lots of pages to be copied and deleted. This paper proposes a data allocation and replacement method based on access frequency by allocating PRAM as checking area of access frequency, log blocks, storing region of hot data in SSD. The proposed method can enhance the performance and lifetime of SSD by storing cold data to flash memory and storing log blocks and frequently accessed data to PRAM and then reducing merge and erase operations. Besides, a data replacement method is used to increase utilization of PRAM which has limitation of capacity. The experimental results show that the ratio of erase operations of the proposed method is 46%, 38% smaller than those of BAST and FAST and the write performance of the proposed method is 34%, 19% higher than those of BAST and FAST, and the read performance of the proposed method is 5%, 3% higher than those of BAST and FAST, respectively.

Effect of Relative Levels of Mineral Admixtures on Strength of Concrete with Ternary Cement Blend

  • Mala, Kanchan;Mullick, A.K.;Jain, K.K.;Singh, P.K.
    • International Journal of Concrete Structures and Materials
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    • v.7 no.3
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    • pp.239-249
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    • 2013
  • In the present scenario to fulfill the demands of sustainable construction, concrete made with multi-blended cement system of OPC and different mineral admixtures, is the judicious choice for the construction industry. Silica fume (SF) and fly ash (FA) are the most commonly used mineral admixtures in ternary blend cement systems. Synergy between the contributions of both on the mechanical properties of the concrete is an important factor. This study reports the effect of replacement of OPC by fly ash (20, 30, 40 and 50 % replacement of OPC) and/or silica fume (7 and 10 %) on the mechanical properties of concrete like compressive strength and split tensile strength, with three different w/b ratio of 0.3, 0.4 and 0.45. The results indicate that, as the total replacement level of OPC in concrete using ternary blend of OPC + FA + SF increases, the strength with respect to control mix increases up to certain replacement level and thereafter decreases. If the cement content of control mixes at each w/b ratio is kept constant, then as w/b ratio decreases, higher percentage of OPC can be replaced with FA + SF to get 28 days strength comparable to the control mix. A new method was proposed to find the efficiency factor of SF and FA individually in ternary blend cement system, based on principle of modified Bolomey's equation for predicting compressive strength of concrete using binary blend cement system. Efficiency factor for SF and FA were always higher in ternary blend cement system than their respective binary blend cement system. Split tensile strength of concrete using binary and ternary cement system were higher than OPC for a given compressive strength level.

Performance comparison of machine learning classification methods for decision of disc cutter replacement of shield TBM (쉴드 TBM 디스크 커터 교체 유무 판단을 위한 머신러닝 분류기법 성능 비교)

  • Kim, Yunhee;Hong, Jiyeon;Kim, Bumjoo
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.22 no.5
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    • pp.575-589
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    • 2020
  • In recent years, Shield TBM construction has been continuously increasing in domestic tunnels. The main excavation tool in the shield TBM construction is a disc cutter which naturally wears during the excavation process and significantly degrades the excavation efficiency. Therefore, it is important to know the appropriate time of the disc cutter replacement. In this study, it is proposed a predictive model that can determine yes/no of disc cutter replacement using machine learning algorithm. To do this, the shield TBM machine data which is highly correlated to the disc cutter wears and the disc cutter replacement from the shield TBM field which is already constructed are used as the input data in the model. Also, the algorithms used in the study were the support vector machine, k-nearest neighbor algorithm, and decision tree algorithm are all classification methods used in machine learning. In order to construct an optimal predictive model and to evaluate the performance of the model, the classification performance evaluation index was compared and analyzed.

The Effects of Home Care Exercise Program on Knee Joint Function and Quality of Life in Patients with Total Knee Replacement Arthroplasty (슬관절 전치환술 환자의 조기퇴원 후 가정간호 운동 프로그램이 슬관절기능 상태와 삶의 질에 미치는 효과)

  • Lee, Mi-Kyoung;Lee, In-Hee;Ju, Jung-Hea;Hwang, Mun-Suk;Seo, Jai-Gon;Sung, Young-Hee
    • Journal of muscle and joint health
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    • v.12 no.2
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    • pp.143-154
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    • 2005
  • Purpose: The aim of this study was to investigate the effects of home care exercise program on knee joint function(WOMAC) and the quality of life in patient with total knee replacement arthroplasty. Method: Forty-one subjects were sampled according to research criteria, and divided into two groups : 21 out of experimental group and 20 out of control group. The patients having treatment of total knee replacement arthroplasty were out of the hospital. After surgery executed, it took 8days for them to recovere their health conditions since 10th day, the experimental group received the home care exercise program per regularly four days interval. Results: 1) After applying home care exercise program, the total score on the WOMAC Index for the control group was $3.09{\pm}.76$. The score of the experimental group was $3.55{\pm}.55$ which is statistically higher than that of the control group. (P=.007). 2) After applying home care exercise program, the score of the quality of life for the control group was $3.09{\pm}.50$. The score of the experimental group was $3.46{\pm}.35$ Which is statistically higher than that of the control group. (P=.007). Conclusion: This figures show that home care exercise program has good results. These findings also indicate that the services of home care exercise program are alternatives for the hospitalization.

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Methodology for Variable Optimization in Injection Molding Process (사출 성형 공정에서의 변수 최적화 방법론)

  • Jung, Young Jin;Kang, Tae Ho;Park, Jeong In;Cho, Joong Yeon;Hong, Ji Soo;Kang, Sung Woo
    • Journal of Korean Society for Quality Management
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    • v.52 no.1
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    • pp.43-56
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    • 2024
  • Purpose: The injection molding process, crucial for plastic shaping, encounters difficulties in sustaining product quality when replacing injection machines. Variations in machine types and outputs between different production lines or factories increase the risk of quality deterioration. In response, the study aims to develop a system that optimally adjusts conditions during the replacement of injection machines linked to molds. Methods: Utilizing a dataset of 12 injection process variables and 52 corresponding sensor variables, a predictive model is crafted using Decision Tree, Random Forest, and XGBoost. Model evaluation is conducted using an 80% training data and a 20% test data split. The dependent variable, classified into five characteristics based on temperature and pressure, guides the prediction model. Bayesian optimization, integrated into the selected model, determines optimal values for process variables during the replacement of injection machines. The iterative convergence of sensor prediction values to the optimum range is visually confirmed, aligning them with the target range. Experimental results validate the proposed approach. Results: Post-experiment analysis indicates the superiority of the XGBoost model across all five characteristics, achieving a combined high performance of 0.81 and a Mean Absolute Error (MAE) of 0.77. The study introduces a method for optimizing initial conditions in the injection process during machine replacement, utilizing Bayesian optimization. This streamlined approach reduces both time and costs, thereby enhancing process efficiency. Conclusion: This research contributes practical insights to the optimization literature, offering valuable guidance for industries seeking streamlined and cost-effective methods for machine replacement in injection molding.