Quantitative Analysis of the Effect of Perforation Interaction on Sand Production Using the Finite Element Method

The study investigates perforation interaction in order to find the optimum perforation design which yields the highest productivity while maintaining mechanical stability. The study is composed of i) evaluation of flow performance and ii) evaluation of mechanical stability. Both evaluations were performed by using the finite element method with multi-perforation mesh to distinguish the effect of perforation interaction. The flow evaluation quantitated the productivity for various cases, allowing us to find the most prolific perforation design. In the stability evaluation, perforation stability was quantitated under various conditions with the effect of perforation interaction. It provides us with a new insight into the effect of shot density on perforation stability

Quantitative Analysis of the Effect of Perforation Interaction on Sand Production Using the Finite Element Method

The study investigates perforation interaction in order to find the optimum perforation design which yields the highest productivity while maintaining mechanical stability. The study is composed of i) evaluation of flow performance and ii) evaluation of mechanical stability. Both evaluations were performed by using the finite element method with multi-perforation mesh to distinguish the effect of perforation interaction. The flow evaluation quantitated the productivity for various cases, allowing us to find the most prolific perforation design. In the stability evaluation, perforation stability was quantitated under various conditions with the effect of perforation interaction. It provides us with a new insight into the effect of shot density on perforation stability

Quantitative Analysis of the Effect of Perforation Interaction on Sand Production Using the Finite Element Method

The study investigates perforation interaction in order to find the optimum perforation design which yields the highest productivity while maintaining mechanical stability. The study is composed of i) evaluation of flow performance and ii) evaluation of mechanical stability. Both evaluations were performed by using the finite element method with multi-perforation mesh to distinguish the effect of perforation interaction. The flow evaluation quantitated the productivity for various cases, allowing us to find the most prolific perforation design. In the stability evaluation, perforation stability was quantitated under various conditions with the effect of perforation interaction. It provides us with a new insight into the effect of shot density on perforation stability

The mineralogy of gold-copper skarn related porphyry at the Batu Hijau deposit, Sumbawa, Indonesia

Clacic gold-copper bearing skarn in the Batu Hijau porphyry deposit is located in the western part of Sumbawa Island, Indonesia. Skarn mineralizations were found at the deep level of the deposit (-450m to -1050mL) by drilling program 2003. No evidence around Batu Hijau has limestone although most skarn are metasomatiz ed from carbonate-rich rock as limestone or marble. Most skarn-type metasomatic alteration and mineralization occurs at the contact of andesitic volcanic rock and intermediate tonalite porphyry intrusion and within intermediate tonalite in some. Although both endoskarn and exoskarn can be developed, it has no clear minerals to known the endoskarn. Exoskarn is more principle skarn zone. The formation of skarn occurred two min stages: (1) prograde and (2) retrograde. The prograde stage is temporally and spatially divided into two sub-stages as early prograde (sub-stage I) and prograde metasomatic (sub-stage II). Sub-stage I begin immediately after the intrusion of the tonalite stock into the calcium rich volcanic rocks. Then, sub-stage II originated with segregation and evolution of a fluid phase in the pluton and its invasion into fractures and micro-fractures of host rocks developed during sub-stage I. The introduction of considerable amount of Fe, Si and Mg led to the large amounts of medium- to coarse-grained anhydrous calc-silicates. From the texture and mineralogy, the retrograde metasomatic stage can be divided into two sub-stages: (a) early retrograde and (sub-stage III) and (b) late retrograde (sub-stage IV). During sub-stage III, the previously formed skarn zones were affected by intense multiple hydro-fracturing phases in the gold-copper bearing stocks. Therefore, the considerable amounts of hydrous calc-silicates (epidote), sulfides (pyrite, chalcopyrite, sphalerite), oxides (magnetite, hematite) and carbonates (calcite) replaced the anhydrous calc-silicates. Sub-stage IV was coexisting with the intrusion of relatively low temperature, more highly oxidizing fluids into skarn system, bringing about partial alteration of the early-formed calc-silicates and developing a series of very fine-grained aggregrates of chlorite, clay, hematite and calcite

A Method to Detect the Syllable Strings of Self-repair in Spontaneous Speech Using N -gram Model

This paper proposes a method to detect the strings of self-repairs occuring in spontaneous speech, which are assumed to be represented with strings of syllables obtained correctly by accoustic processing, using n-gram model and Markov models of syllables. This method os decomposed of the following two steps: The first step is to detect all of the pairs (celled as n-gram pair) with the same substrings appeared in dialogue sentence using n-gram extraction methods. The second step is to determine whether n-gram pair is self-repair or not. using Markov models of syllables. This method is experimentally evaluated to be effective using ATR database of dialogue

Fetal presentation of Klippel-Trénaunay-Weber syndrome with massive pleural effusion and ascites

Background: Although fetuses with Klippel-Trénaunay- Weber syndrome (KTS) show various morphological abnormalities on imaging studies, fetal presentation with hydrops fetalis is relatively uncommon in KTS. Case: A 28-year-old Japanese woman who had previously given birth to a healthy infant was referred to us at gestational week (GW) 22 due to huge pleural effusion and ascites. The possibility of fetal pulmonary hypoplasia prompted us to place bilateral thoracoamniotic shunts at GW 23 after extensive discussion with both parents. The bilateral shunts were effective in preventing recurrence of pleural effusion. However, ascites gradually increased and clinical signs of fetal cardiac failure necessitated cesarean section at GW 34. A male infant, weighing 4252 g at birth and 2860 g after removal of ascites, survived to the neonatal period and did not require oxygen after postnatal day 63. The infant left hospital on day 103 with a diagnosis of KTS. Conclusion: Fetuses with KTS may present with massive pleural effusion and ascites. Thoracoamniotic shunting may be effective in such hydropic fetuses with KTS

Essential thrombocythemia as a risk factor for stillbirth

Introduction: The risk of abortion is known to be high in women with essential thrombocythemia (ET). However, a few studies have focused on the risk of stillbirth among fetuses reaching gestational age compatible with life. Methods: Review of medical charts of pregnant women with ET who received cares at a single center between January 2003 and June 2013 and the English literature in which more than 20 pregnancies with ET were dealt with regarding outcomes. Outcomes were classified into three categories: spontaneous abortion or preterm delivery before GW 24, stillbirth at and after GW 24, and live birth (LB). Japan national statistics was used to estimate the risk of stillbirth among women with GW 22 or more. Results: In all nine pregnancies in four women with ET at our hospital, two miscarriages, one stillbirth (intrauterine death at GW 35), and six LBs occurred. There were six reports in the English literature in which a total of 374 pregnancy outcomes were described: 110 miscarriages (29%), 14 stillbirths (3.7% of all 374 pregnancies and 5.3% of 264 pregnancies with GW >= 24), and 250 LBs (67%) occurred. Japan national statistics between 1995 and 2011 indicated that the risk of stillbirth was less than 0.50% among women with GW >= 22. Conclusions: The risk of still birth was extremely high among women with ET. More intensified monitoring of fetal wellbeing may be required to improve outcome of pregnancy complicated with ET. (C) 2013 Elsevier Ltd. All rights reserved

加速器中性子源による環境トレーサー132Csの製造及び実用化に向けた検討

修士（工学