287 research outputs found

    Process Fault Diagnosis using Neural Networks and Fault Tree Analysis Information

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    Neural nets have recently become the focus of much attention, largely because of their wide range of complex and nonlinear problems. This paper presents a new integrated approach using neural networks for diagnosing process failures. The fault propagation in process is modeled by causal relationships from the fault tree and its minimal cut sets. The measurement patterns required for training and testing the neural network were obtained from fault propagation model. The network is able to diagnose even in the presence of malfunction of certain sensors. We demonstrate via a nitric acid cooler process how the neural network can learn and successfully diagnose the faults

    Fatal traffic accidents and forensic medicine

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    AbstractIn the event of a traffic accident fatality, the death is reported as an “unusual death,” an inquest is conducted, and, if necessary, a forensic autopsy is performed to prove any causal relationship between the accident and the death, identify the vehicle at fault, and determine the cause of the accident. A forensic autopsy of a traffic accident fatality needs to both determine the cause of death and identify the mechanism of injury, an analytical task that requires observation of three major traffic accident factors: the body, the vehicles involved, and the scene of the accident. Also crucial to determining the cause of death is the process of looking into whether the people involved in the accident had any diseases that might affect their driving performance or were under the influence of alcohol or drugs. In order to reduce the number of people killed in traffic accidents, it will be important to promote joint research uniting forensic medicine, clinical medicine, automotive engineering, and road engineering, take measures to limit the impact of inebriated pedestrians and pedestrians suffering from dementia, and ensure proper screening of alcohol and illegal drug consumption in drivers

    Effect of sterical stabilization on macrophage uptake in vitro and on thickness of the fixed aqueous layer of liposomes made from alkylphosphocholines

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    AbstractA serious problem using liposomes for therapeutic purposes is the fast removal from blood circulation by components of the reticuloendothelial system (RES) most likely after opsonization of the vesicles. This study was performed to quantify the reduction in macrophage uptake in vitro of sterically stabilized liposomes (PEG-liposomes) prepared from hexadecylphosphocholine, cholesterol and poly(ethylene glycol2000) distearoylphosphoethanolamine (PEG2000DSPE) for the first time. The uptake was determined using HPC-liposomes of different defined size (125, 250 and 1000 nm) without and with sterical stabilization by incorporating 5 mol% of PEG2000DSPE. HPTS was used as fluorescence marker allowing the discrimination between general uptake and the part of liposomes internalized into the low pH-compartment (Daleke, L.D., Hong, K. and Papahadjopoulos, D. (1990) Biochim. Biophys. Acta 1024, 352–366). Liposomal uptake by J774 mouse macrophage-like cells was time-dependent. Both the uptake and internalization were clearly reduced for PEG-liposomes compared to plain liposomes. Sterical stabilization reduced the general uptake of liposomes in vitro by more than 50% and the internalization by about 50–60%. PEG-liposomes additionally showed a delay in internalization into the macrophages during the first 6 h. Size of used liposomes had only a minor influence on liposomal uptake but highest concentration of lipid was found for large multilammelar vesicles (MLV). The fixed aqueous layer thickness (FALT) was determined by zeta potential measurements of plain and sterically stabilised HPC-liposomes (100 nm) in solutions of different ion concentrations. The calculation of the thickness was based on the linear correlation between ln ζ (zeta-potential) and κ (Debye Hückel-Parameter). FALT was calculated and found to be for plain HPC-liposomes 0.83 ± 0.17 nm and for PEG-HPC-liposomes 3.57 ± 0.17 nm. Exchange of the HPC by an alkylphospholipid with different head group has no or only minor effect (PEG-OPP-liposomes 3.44 ± 0.31 nm). Thus the reduced uptake of HPC-LUVET correlates with an increased thickness of the fixed aqueous layer around these liposomes and could support the hypothesis that the thickness is an important property responsible for preventing opsonization and resulting finally in a reduced macrophage uptake

    Fuzzy fault diagnostic system based on fault tree analysis

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    A method is presented for process fault diagnosis using information from fault tree analysis and uncertainty/imprecision of data. Fault tree analysis, which has been used as a method of system reliability/safety analysis, provides a procedure for identifying failures within a process. A fuzzy fault diagnostic system is constructed which uses the fuzzy fault tree analysis to represent a knowledge of the causal relationships in process operation and control system. The proposed method is applied successfully to a nitric acid cooler process plant</p

    Fabrication of resistively-coupled single-electron device using an array of gold nanoparticles

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    We demonstrated one type of single-electron device that exhibited electrical characteristics similar to those of resistively-coupled SE transistor (R-SET) at 77 K and room temperature (287 K). Three Au electrodes on an oxidized Si chip served as drain, source, and gate electrodes were formed using electron-beam lithography and evaporation techniques. A narrow (70-nm-wide) gate electrode was patterned using thermal evaporation, whereas wide (800-nm-wide) drain and source electrodes were made using shadow evaporation. Subsequently, aqueous solution of citric acid and 15-nm-diameter gold nanoparticles (Au NPs) and toluene solution of 3-nm-diameter Au NPs chemisorbed via decanethiol were dropped on the chip to make the connections between the electrodes. Current–voltage characteristics between the drain and source electrodes exhibited Coulomb blockade (CB) at both 77 and 287 K. Dependence of the CB region on the gate voltage was similar to that of an R-SET. Simulation results of the model based on the scanning electron microscopy image of the device could reproduce the characteristics like the R-SET

    Gate-tuned negative differential resistance observed at room temperature in an array of gold nanoparticles

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    We fabricated a single-electron (SE) device using gold nanoparticles (Au NPs). Drain, source, and gate electrodes on a SiO2/Si substrate were formed using electron beam lithography (EBL) and thermal evaporation of Au. Subsequently, solutions of 3-nm-diameter and 5-nm-diameter Au NPs were dropped on the device to make current paths through Au NPs among the electrodes. Measurements of the device exhibited negative differential resistance (NDR) in the current-voltage characteristics between the drain and source electrodes at room temperature (298 K). The NDR behavior was tuned by applying a gate voltage

    Thin anterior uterine wall with incomplete uterine rupture in a primigravida detected by palpation and ultrasound: a case report

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    <p>Abstract</p> <p>Introduction</p> <p>Uterine rupture is an obstetric complication associated with significant maternal and fetal morbidity and mortality. This disorder usually occurs with a scarred uterus, especially in a uterus with prior Cesarean section. Uterine sacculation or diverticulum may also lead to a thin uterine wall during pregnancy.</p> <p>Case presentation</p> <p>A 27-year-old Japanese primigravid woman was admitted to our hospital due to weak, irregular uterine contractions in her 38<sup>th </sup>week of gestation. She had no past history of uterine surgery or known diseases. A hard mass was palpable in her abdomen. An ultrasound revealed that the anterior uterine wall was thin and bulging, with a fetal minor part beneath it which corresponded to the palpated mass. A Cesarean section was performed which revealed a thin anterior uterine wall with incomplete uterine rupture. The woman and baby were healthy.</p> <p>Conclusions</p> <p>Although extremely rare, an unscarred primigravid uterus can undergo incomplete rupture even without discernable risk factors or labor pains. Abdominal palpation and ultrasound may be useful in detecting this condition.</p

    One-dimensional array of small tunnel junctions fabricated using 30-nm-diameter gold nanoparticles placed in a 140-nm-wide resist groove

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    We present percolative arrays of gold nanoparticles (NPs) formed in a resist groove. To enhance the con nection probability, the width of the resist groove (140 nm) was designed to be approximately five times larger than the diameter of gold NPs (30 nm). Two-stage deposition of gold NPs was employed to form bridge connections between the source and drain electrodes. Dithiol molecules coated on surfaces of gold NPs worked as tunnel barriers. 5 of 12 samples exhibited Coulomb blockade characteristics, in one of which the gate response was confirmed

    Effect of acidity on the physicochemical properties of α- and β-chitin nanofibers

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    Published online 11 Apr 2017We have investigated whether acidity can be used to control the physicochemical properties of chitin nanofibers (ChNFs). In this study, we define acidity as the molar ratio of dissociated protons from the acid to the amino groups in the raw chitin powder. The effect of acidity on the physicochemical properties of α- and β-ChNFs was compared. The transmittance and viscosity of the β-ChNFs drastically and continuously increased with increasing acidity, while those of the α-ChNFs were not affected by acidity. These differences are because of the higher ability for cationization based on the more flexible crystal structure of β-chitin than α-chitin. In addition, the effect of the acid species on the transmittance of β-ChNFs was investigated. The transmittance of β-ChNFs can be expressed by the acidity regardless of the acid species, such as hydrochloric acid, phosphoric acid, and acetic acid. These results indicate that the acidity defined in this work is an effective parameter to define and control the physicochemical properties of ChNFs.ArticleINTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES. 102:358-366 (2017)journal articl

    Effect of Keishi-bukuryo-gan on asymptomatic cerebral infarction for short term

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    無症候性脳梗塞患者に対する桂枝茯苓丸の効果を検討した。142例(男性32例,女性110例,平均年齢68.9才)を対象とし,副作用のため内服を中止した3例を除く139例に対して,桂枝茯苓丸エキス1日量7.5gを12週間投与した。投与開始時と比較して,改訂長谷川式簡易知能評価スケール,Apathyスケール(やる気スケール),SDS(うつ状態スケール)は有意に改善した。また,頭重感,頭痛,めまいの自覚症状も桂枝茯苓丸の投与により改善し,拡張期血圧は投与前に比べ有意に低下した。これらの結果から,桂枝茯苓丸が無症候性脳梗塞に伴う認知機能の低下,精神症状や自覚症状の悪化に対して有効である可能性が示唆された。 The efficacy of Keishi-bukuryo-gan in patients suffering from asymptomatic cerebral infarction was studied. 142 patients, 32 males and 110 females, with a mean age of 68.9 years, were enrolled and analyzed, and 139 completed the study. They were given Keishi-bukuryo-gan extract (7.5g/day) three times a day for 12 weeks. In comparison to the beginning of the study, Keishi-bukuryo-gan showed improvement with statistical significance in the mean revised version of Hasegawa\u27s dementia scale, Apathy scale and Self-rating depression scale. The number of patients with subjective symptoms as headdullness, headache and dizziness decreased by the treatment with Keishi-bukuryo-gan, and diastolic blood pressure was decreased with statistical significance as compared to the beginning of the study. These results suggest that Keishi-bukuryo-gan is effective against dysfunction of acknowledgment, emotional disorder and subjective symptoms with asymptomatic cerebral infarction
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