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Accurate modeling of a photon-counting detector is essential for detector design and performance evaluation, system-level performance investigation, and image reconstruction. This modeling is complicated because various factors involve and couple together, including X-ray interactions, fluorescence X-rays escaping and absorption, primary charge cloud distribution, charge diffusion and interactions (repulsion), and charge trapping. In this article, we adapted a comprehensive detector modeling approach, which incorporates all these relevant factors into account. This approach allowed us to evaluate the impact of different physical effects on the detector energy response. In particular, we evaluated the impact of anode street impact on the detector energy response. We found the conductivity difference between the anode street surface and the bulk region within the sensor volume could significantly affect the detector energy response, including reducing peak events and increasing the low-energy tail events. As compared to without considering the anode street conductivity difference, the detection efficiency at 60 keV could be reduced by 5%–15% (40- $\mu \text{m}$ street size), and 12%–33% (70- $\mu \text{m}$ street size) when the threshold was varied from 45 to 57 keV.

Mathematical modeling of the fermentation process is useful for understanding the influence of operating parameters on target production and control performance, depending on the situation, to stabilize the target production at a high-level. However, the previous approaches using physical modeling methods and traditional knowledge-based methods are difficult to apply on working fermentors at a commercial plant scale because they have unknown and unmeasured parameters involved in target production. This study focused on developing an ensemble learning model that can predict the amino acid fermentation process behavior based on observation values, which can be obtained from fermentation tanks and future control input. The results revealed the influence of each control input on lysine production during the culturing period. Furthermore, high-order stability, which achieved the target trajectory for lysine production, was realized using dynamic fermentation controls. Additionally, this study demonstrates that the fermentation behavior on a commercial plant scale is reproduced using the ensemble device. The ensemble learning model will provide novel control system with data-science based model of Industry 4.0 in the field of biotechnological processes.

Monitoring cell growth and target production in working fermentors is important for stabilizing high level production. In this study, we developed a novel soft sensor for estimating the concentration of a target product (lysine), substrate (sucrose), and bacterial cell in commercially working fermentors using machine learning combined with available on-line process data. The lysine concentration was accurately estimated in both linear and nonlinear models; however, the nonlinear models were also suitable for estimating the concentrations of sucrose and bacterial cells. Data enhancement by time interpolation improved the model prediction accuracy and eliminated unnecessary fluctuations. Furthermore, the soft sensor developed based on the dataset of the same process parameters in multiple fermentor tanks successfully estimated the fermentation behavior of each tank. Machine learning-based soft sensors may represent a novel monitoring system for digital transformation in the field of biotechnological processes.

Fracture tests and finite element analysis were conducted to evaluate the temperature dependence of the effective surface energy γ mm corresponding to microcrack propagation across the grain boundary of steels. Steels containing coarse cementite particles were prepared to enable γ mm evaluation. The critical fracture stress of microcrack propagation across the grain boundary is considered larger than the critical fracture stress of microcrack propagation across the interface between a cementite particle and a ferrite grain in these steels because of the large cementite particles; therefore, local fracture stress estimated by finite element analysis and fracture initiation site obtained by fractography reflect the critical fracture stress of microcrack propagation across the grain boundary. Thus, the accuracy of γ mm calculated from local fracture stress is observed to be enhanced by employing the steels prepared for the present study. In addition, the effect of nickel on γ mm was studied using steels containing different concentrations of nickel. Values of γ mm were evaluated considering both the direction of a neighboring facet relative to the crack initiation facet and the mixed mode stress intensity factors. The authors proposed a new temperature dependence of γ mm . Additionally, the negligible effect of nickel addition on γ mm was observed. The results of the present study can be used effectively to develop a probabilistic cleavage fracture model based on microstructural information.

We developed the first model to evaluate unstable ductile crack arrestability in offshore pipelines. The proposed model is an integrated one-dimensional model with four sub-models to calculate (a) pipe deformation, (b) gas flow inside pipe, (c) bubble growth, and (d) crack propagation. We validated the proposed model by applying it to two types of tests: laboratory scale underwater rupture tests and existing data of a full-scale burst test of an offshore pipeline. In addition, the calculation results of the proposed model showed that a deep water depth results in increased unstable crack arrestability of the pipeline.

Prevention of unstable ductile crack propagation has been a great issue in pipeline industry. For appropriate pipe design, the authors developed a numerical model to predict unstable ductile crack propagation/arrest using finite difference method. The features of the model are as follows: (1) pipe deformation and gas decompression are formulated based on one-dimensional partial differential equations; (2) the interaction among pipe deformation, gas decompression and crack propagation is considered; (3) soil backfill effect, which constrains pipe deformation, is considered as added density. In this paper, the model is described in detail, and applied to full-scale natural gas pipe burst tests.

In this research, atmospheric and underwater small-scale pipe rupture disk tests were conducted. Tested pipes with rupture disk were pressurized by pure nitrogen, in which internal pressure changes and external pressure changes were measured by pressure transducers. By comparing results of the underwater tests with results of the atmospheric tests, water effects were clarified: (1) gas decompression in the underwater tests delays due to constrained gas leak by bubble generation and growth as compared to gas decompression in the atmospheric tests, and (2) larger external pressure changes were measured in the underwater tests. In addition, 1D finite-difference based coupled model for gas decompression, in which gas flow inside a pipe and bubble growth are considered, was developed. In the model, governing equations for gas flow inside a pipe and a bubble are derived from mass conservation law and momentum conservation law assuming isentropic changes of gas. Bubble growth is formulated based on Rayleigh-Plesset equation. The calculated results for the rupture disk tests using the model showed good agreements with the experimental results, which analytically clarified the above stated water effects. This research reveals an importance of considering the water effects in evaluating fractures in offshore pipelines. In the future, it is expected that the model is extended to incorporate crack propagation and pipe deformation together with gas decompression and bubble growth.

Intramural duodenal haematoma (IDH) is a rare condition forming haematoma within the wall of the duodenum, which was first reported in 1838 by MacLauchlan.1 IDH derived from acute or chronic pancreatitis is rarely described, the mechanism remaining unknown. A 65-year-old man with history of heavy drinking and chronic hepatitis was admitted to our hospital with sudden vomiting and right-lateral abdominal pain. Abdominal pain and vomiting continued after admission, so a nasogastric tube was inserted. Contrast-enhanced CT scans of the abdomen found a 60×80 mm heterogeneous mass with intraluminal leakage of contrast agent-like bleeding along the second portion of the duodenum, diffuse expansion of the pancreatic duct with pancreatic stone and ascites on the surface of the liver (figure 1). We first considered whether …

Critical CTOD is widely used as a fracture toughness parameter for structural steels. Critical CTOD often has a scatter of more than one order of magnitude. To explain this scatter, Beremin proposed a model called Weibull stress or Beremin model, but some researches cast doubts on the model. Some models were proposed so that they consider microcrack nucleation by taking plastic strain into account. However, these models cannot completely describe experiments, nor did they calculate the scatter of fracture initiation points. The aim of the present paper is to propose a new model which more precisely predict fracture toughnesses as well as fracture initiation points.

In the present study, three-dimensional cleavage crack path prediction model is proposed. The model is based on the local fracture stress criterion in which three candidates for a cleavage plane in a computational element is assumed and the one which has maximum value of normal stress divided by local fracture stress is selected. In this model, normal stress acting on each plane is obtained by local stress intensity factor which is calculated by combination of approximate solutions where crack front non-straightness, crack surface irregularity and crack closing force acting at ridges between crack planes are considered. The model also incorporates multiaxial stress field and non-uniform toughness distribution. Therefore, this model is applied to welded joint of ESSO test where welding residual stress and non-uniform toughness distribution exist, and the predicted results of crack paths show a general agreement with the test results. Parametric study is also conducted in order to discuss the effects of applied stress, welding residual stress, toughness distribution and type of welding groove on brittle crack path behavior.

We describe the results of immunological studies, reaction kinetics and epitope localization of six inhibitor antibodies to factor IX (FIX) developed in severe haemophilia B patients. Three of the six patients had suffered recent anaphylactoid reactions to FIX concentrates, two others had in the past and one had none. All six inhibitors rapidly inactivated FIX activity in vitro, and the prominent immunoglobulin (IgG) subclass of the antibody was IgG4 when analysed with ELISA. Interestingly, we found an additional IgG1 component in the antibody samples from the patients who had recently experienced anaphylactoid reactions to FIX. When analysed with Western blotting in these three patients, the IgG4 antibody bound with enhanced affinity to the heavy chain or the light chain of FIX, and in two of the three the IgG1 antibody also bound strongly to the FIX heavy chain. The results suggest that the heavy chain of FIX might play a more significant role than the light chain in the pathogenesis of anaphylactoid reactions in haemophilia B patients with FIX inhibitors.

症例は63歳の女性で，閉塞性黄疸で当院に入院となった．黄疸は保存的治療にて軽快するも，腹部CTで肝側の胆嚢内に淡く造影効果を受ける45×50 mmの乳頭型腫瘍とNo.12c，No.13aに著明に腫大したリンパ節を認め，胆嚢癌の診断で手術を施行した．膵頭部領域のリンパ節は膵実質との線維性癒着のみで剥離が容易であった．胆嚢床切徐を伴う胆嚢摘出術，肝外胆管切徐とD2リンパ節郭清，肝管空腸吻合術を施行した．胆嚢内には多量の粘液を認め，病理組織学的には，pap，mp，medullary type，INFα，ly0，v0，pn0，pHinf0，pBinf0，pPV0，pA0，pBM0，pHM0，pEM0，n2（＋），（2/13，No12c，13a），fStageIIIであった．消長した閉塞性黄疸は産生された粘液によるものと考えた．粘液産生胆嚢癌はまれであり，文献的考察を加えて報告する．

n° spécial Full-field Measurements in Composites Testing and Analysis; International audience; Meso-scale (unit cell of an impregnated textile reinforcement) finite element (FE) modelling of textile composites is a powerful tool for homogenisation of mechanical properties, study of stress–strain fields inside the unit cell, determination of damage initiation conditions and sites and simulation of damage development and associated deterioration of the homogenised mechanical properties of the composite. Validation of meso-FE modelling requires registration of details of the deformed state on the scale of individual yarns inside the textile, registered using full-field strain measurements on the surface of the sample. The paper presents examples of such a validation of meso-FE models of woven (carbon/epoxy and glass/polypropylene) and braided (carbon/epoxy) composites. Digital image correlation and digital phase shifting grating shearography are used for full-field strain registration. The resolution of the strain field during elastic deformation is improved and damage onset is identified using time-dependent linear regression of the registered field.

A femoral Prosthesis Stem made from composite material is investigating to apply to real body. The purpose of this study is to propose a design method of novel composite stem. Finite element models of stem and femur have been developed by using CT images. Some design parameters of the stem have been described and the effect of mechanical properties on the femur has been also described and compared with a traditional metal stem. The evaluation procedure for the stem has been proposed and been applied to a composite stem. It is revealed that the stem made of composite is more effective than the traditional stem made of metal.

To make an expansion of composite consumption ever widening with use at demanding and safety critical applications, it is important to establish the evaluation technique of the strength, the safety, etc. To reach the goal with a useful reliable technique, we have developed a numerical simulation program on damage development of composites based on damage mechanics. The following points are the keys to simulate the mechanical behavior; (1) The generation technique of FE model with yarns and matrix, (2) The classification of anisotropic damage mode based on damage mechanics, (3) Multi-scale modeling by Mesh superposition method. In this paper, the numerical technique and the results of multi-scale analysis of woven composites are described.

Fiber reinforced composite materials have been applied widely to many structures, because they have some advantages like easy handling, high specific strength, etc. The numerical method like finite element method has been applied to design and to evaluate the material properties and behavior as the development of Computer Aided Engineering. It is very difficult to calculate with accuracy not only in structural scale but also in detail material scale (for example, the order of fiber diameter) by the traditional FEM, becausecompositematerials like woven fabric composites have the geometrical complexityand the large difference between above mentioned scales. The development of multi-scale analysis method is one of the major topics in computational mechanics. Mesh superpositionis one of multi-scale analysis methods and is an effective method to solve the problems which have the large difference between the structure scale and the reinforcement scale. We have expanded the finite element mesh superposition method with 3 scales and have defined as M3 (Macro-Meso-Micro) method. In this paper, we have proposed a new approach method combined with M3 method and homogenized method to obtain the mechanical properties and to simulate the behavior of woven fabric composites. In addition, the elastic-plastic mechanics and the damage mechanics have been introduced into M3 method to investigate the effects of matrix-crack on the structural and material properties. From the numerical results, it is revealed that it is very useful for the evaluation of mechanical properties of composite materials.

To predict the mechanical properties of composite materials by using computer is complicated, because it is difficult to model directly by ordinary FEM. A calculation method by using the mesh superposition method and periodic boundary condition has been proposed in order to obtain the equivalent mechanical properties of composite materials easily. The numerical results by proposed method have shown good agreement with ones by the traditional procedure. The proposed method is efficient for the materials with complicated structure like woven fabric composites etc.

We prospectively investigated whether the wound-protective Alexis (Applied Medical, Rancho Santa Margarita, CA) wound retractor was effective in preventing surgical site infection (SSI).We examined the actual condition of SSI in a 12-month randomized, controlled trial consisting of 221 patients who had undergone nontraumatic gastrointestinal surgery. The patients were divided into a With Alexis retractor group (n = 111) and a Without Alexis retractor group (n = 110). We also analyzed SSI separately on the basis of surgical sites such as gastric surgery or colorectal surgery.Overall estimation showed a significant decrease in wound infection (superficial incisional SSI) in the With Alexis retractor group. In the analysis based on surgical sites, a significant decrease in wound infection was noted in the With Alexis retractor group, the members of which had undergone colorectal surgery. There was no significant difference between the two groups in the occurrence of organ/space SSI, including anastomotic leak or intraperitoneal abscess.It was suggested that the use of the Alexis wound retractor would protect surgical wounds from contamination by bacteria and thus prevent infection.

We developed an image recognition processor, “Visconti,” based on a configurable processor. Three VLIW processors that execute three instructions in parallel are integrated into a single chip with peripheral modules such as video I/Os and an SDRAM controller. Each VLIW processor has a RISC processor core and a VLIW coprocessor dedicated to image processing. The coprocessor executes SIMD instructions such as 8-parallel byte. Visconti was fabricated using 0.13μm CMOS technology, operates at 150MHz, and consumes about 1W. We present actual application examples of Visconti, onboard surveillance for automobiles and face recognition. Compared to cases in which only the processor core is used, execution speed per one processor increases about 16 times for onboard surveillance and about five times per three processors for face recognition. These applications can be processed in real time.

A service load like random load has been analyzed by the rain flow method extensively. When the reliability of a structure is estimated, mean stresses on fatigue life are probably ignored because it is not easy to measure. The purpose of this study is to propose a practical estimation method of a structural reliability for fatigue under service loads by Miner's law. In addition, the fatigue tests to obtain S-N curve is carried out under constant amplitude loading. However, the each stress ratio of cyclic stress counted with rain flow method is different. In the proposed method, the effect of stress ratio has been considered by fatigue limit diagram with failure probability. On this diagram, the increment of cumulative cycle ratio ΔDpf for each cyclic stress can be calculated with failure probability by a computer program. The expected life Npf is defined as the period when Dpf reaches 1.0. If we assume the ergodicity of the sampling time T, Npf is T/Dpf. It gives fatigue life distribution, when a structure is under service loads. In conclusion, we have got a reliability curve of the structure for fatigue life. This curve can be obtained with service load or design stress easily by using our developed program. This proposed method is practical and the industrial applicability is wide.

It is very important for the damage tolerance design of a structure to reveal the behavior of fatigue cracks of the used material. They have some uncertainties, the random applied loads or the residual strength caused by manufacturing process and so on. It is difficult to evaluate the behaviors of real fatigue cracks. In this paper, an evaluation method for fatigue life based on fatigue crack length has been proposed. Fokker-Planck equation, which can describe fatigue crack propagation under random load and random propagation resistance, has been proposed. The distribution of fatigue life has been analyzed by combining both of the distribution of crack initiation life and the distribution of propagation life.

Diaphragms made of a stainless steel plates are widely used as switching parts in electronic devices. Due to the cyclic loading applied to these diaphragms, the estimation of the lives of diaphragms is important to decide that of the electronic devices. The fatigue characteristic of the diaphragm must be discussed with considering the large scatter of material properties induced by the anisotropy. In this study, the tensile and the fatigue tests have been carried out some specimens with a direction to cold rolling direction. A pulley driving system was adopted as a fatigue testing apparatus because the load can be easily applied even when the thickness of the specimen is less than 0.1mm. From the experimental results, we have decided the S-N curve by applying large scatter of fatigue lives to the probability distribution based on reliability, and drew the Goodman diagram to avoid the effect of the mean stress. The obtained results can be used for fatigue design considering the anisotropy in the case of high cycle fatigue for diaphragms.

Fatigue characteristics of a metal diaphragm in a light touch switch are evaluated with experimental approach considering a cyclic load acting on it. The approach consumes much time and costs for evaluation. In previous paper, we have described that the mechanical properties of stainless steel have anisotropy and the fatigue characteristic must be discussed with considering the large scatter of material properties induced by the anisotropy. Therefore, the purpose of this study is to establish a simple method to evaluate the reliability of diaphragms with the consideration of anisotropy. The proposed approach consists of three procedures. Firstly, residual stress after press forming is evaluated by FEM, and feeling curves when the pushing load by is applied on the diaphragm are also analyzed. And, the stress amplitude and the mean stress at every point on the diaphragm can be calculated. Secondly, the experimental database about S-N curve and Goodman diagram considering the effect of anisotropy have been prepared. Finally, the fatigue lives considering failure probability on the diaphragm can be estimated by comparison of Goodman diagram and numerical results. From the obtained results, it is revealed that the proposed approach is very useful for the reliability evaluation of the diaphragm.

Diaphragms made of stainless steel plates are widely used as switching parts in electrical devices. Since the cyclic loading is applied to these diaphragms by the repeated switching mode of on/off, the estimation of the fatigue life of diaphragms is very important. The fatigue characteristics of the diaphragm must be discussed considering the large scatter of material properties induced by the anisotropy. In this study, the tensile and the fatigue tests have been carried out for some specimens with a direction to cold rolling direction. A pulley driving system has been adopted as a fatigue testing apparatus because the load can be applied even when the thickness of the specimen is less than 0.1mm. From the experiment, it is recognized that the experimental data is scattered largely. In addition, the residual stress is generated by a press forming process and the stress acts on the diaphragm as a mean stress. In order to estimate the reliability of a diaphragm, therefore, the Goodman diagram with a design margin which can be considered the mean stress for fatigue can be obtained. We have proposed the method which can evaluate the reliability of a diaphragm to design life by Goodman diagram.