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名古屋大学博士学位論文 学位の種類 : 博士(医学)(論文) 学位授与年月日:平成5年2月19日 竹中晃氏の博士論文として提出された

This study used the multiple methods of classroom observation, interview with teachers and students, and paper-and-pencil test to investigate the ability development of seventh-grade students in learning two-dimensional linear systems of equations and the corresponding error analysis. Hopefully, the results of this study can be as a reference for the middle school math teachers to plan the suitable teaching strategies when they teach two-dimensional linear systems of equations to their students. At the beginning, the researcher entered two seventh-grade classrooms of one middle school in Kaohsiung to make the preliminary observations and let students (also the teachers) to get used to the appearance of the researcher in the classroom during the period that one-variable linear equations were taught. Subsequently, the formal observations were carried out for 40 class periods that two-dimensional linear systems of equations were taught. All the observations made about how teachers taught and how students learned were recorded and content analyzed. Two paper-and-pencil tests were administered during the period of preliminary observations. And three paper-and pencil tests were given during the period of the formal observations. All the test results were collected and analyzed in numerous ways. Based on the literature survey and the interviews with six middle school math teachers, all relevant abilities of mastering two-dimensional linear systems of equations were classified into three categories: Character Symbols (10 sub-abilities), Operational Principals (five sub-abilities), and Other Abilities (16 sub-abilities). Based on the results of the content analyses of classroom observations and the error analyses of five paper-and-pencils tests for each sub-abilities of mastering the subject, it was observed that during the period of developing the abilities on solving two-dimensional linear systems of equations, most students showed some signs of obstacles and puzzles. Even by the end of the course on two-dimensional linear systems of equations, most students still did not master the subject well. Based on the results of this study, it is proposed that the length of teaching period needs to be increased and more efficient learning strategies need to be introduced to the students when two-dimensional linear systems of equations are taught.

We have studied the electronic properties of AlxGa1-xN/GaN heterostructures by using Shubnikov¡Vde Haas(SdH) measurement. Two SdH oscillations were detected on the samples of x=0.35 and 0.31, due to the population of the first two subbands with the energy separations of 128 and 109 meV, respectively. For the sample of x=0.25, two SdH oscillations beat each other, probably due to a finite zero-field spin splitting. The spin-splitting energy is equal to 9.0 meV. The samples also showed a persistent photoconductivity effect after illuminating by blue light-emitting diode. For the part of experiment , we installed a "Regulator" on low temperature and high magnetic field system, in order to control the temperature of sample from 0.3K to 10K accurately. For the convenience of SdH measurements at different tempertures.

Abstract The development of colorectal cancer ( CRC ) is believed to follow series progress of pathological changes and with correspondent genetic changes of many genes. This includes intestinal epithelial crypts, aberrant focus, adenoma and carcinoma, each of that commonly involved genetic and proteomic alterations. And in genetic level, it usually includes mutations of APC, p53, K-ras and microsatellite instability. The somatic mutations of APC gene mostly occur in MCR ( Mutation Cluster Region ) in codon 1286-1513. The p53 mutations is dispersed in whole gene with 3 hot spots: codon 175, 248 273. K-ras codon 12 and 13 mutations is preferentially involved in polyps growth of CRC. And microsatellite instability is found in 15-25% CRC patients. We collect polyps and various stages CRC samples in Taiwan, and design 6 primer pairs of APC and p53 which is widely used in western countries to analyze mutations of the local CRC genetic changes. We also use two-dimensional electrophoresis and mass spectrometry to identify protein expression changes in CRC. We have found 30 proteins that exhibited either a significant decrease or increase between normal colon tissue and carcinoma, and 3 out of ( TSD1, TSD2, and TSD3 ) these were significantly associated with tumor progression. TSD3 is annotated by mass spectrometry and is identified to be a c1q-related protein. Though there are no report on the function of c1q-related protein, a NCBI virtual northern analysis shows its expression is varied in various cancer. On the other hand, there are only about 56 % genetic changes of APC and p53 during carcinogensis, which is much less than the 70-85 % mutational rate in western CRC patients. It indicates different genetic mutational pattern of CRC in Taiwan.

Ultrasonic guided waves having the ability to inspect long distance pipeline is one of the non-destructive testing methods. The reflected echoes as well as mode conversion phenomena indicate the presence of defect or other features on the pipe. To study the feasibility of guided wave quantification of sludge inside pipes, this thesis applies the transient simulation by finite element method to analyze the scattering of the guided T(0,1) mode by non-axisymmetry layer inside a pipe. Both the Two-dimensional Fourier transform and Wavelet transform were used to process the signals to understand the scattering behavior. The numerical analyses revealed the following phenomena. First, partial energy of the T(0,1) mode will leaky into the asymmetric layer when T(0,1) mode propagates along the pipe and impinge onto the asymmetric layer inside a pipe named a composite pipe. The T(0,1) mode will convert to the propagating modes of the composite pipe model. Secondly, the composite pipe will reflect the T(0,1) and modes of higher circumferential order. The percentage of asymmetric layer inside a pipe is one of the parameter controlling the reflection spectrum response. To sum up, in this study, the reflection spectrum response could used to predict the quantified accumulation of sludge by wavelet transform through time-frequency analysis.

Models based on various types of automata are ubiquitous in modern science. These models allow reasoning about deep theoretical questions and provide a basis for the development of efficient algorithms to solve related computational problems. This work discusses several types of automata used in such models, including cellular automata and mandatory results automata. The first part of this work is dedicated to cellular automata. These automata form an important class of discrete dynamical systems widely used to model physical, biological, and chemical processes. Here we discuss a way to study the dynamics of one-dimensional cellular automata through the theory of two-dimensional picture languages. The connection between cellular automata and picture languages stems from the fact that the set of all space-time diagrams of a cellular automaton defines a picture language. We will discuss a hierarchy of cellular automata based on the complexity of the picture languages that they define. In addition to this, we present a characterization of cellular automata that can be described by finite-state transducers. The second part of this work presents a theory of runtime enforcement based on mech- anism models called Mandatory Results Automata (MRAs). MRAs can monitor and trans- form security-relevant actions and their results. Because previous work could not model general security monitors transforming results, MRAs capture realistic behaviors outside the scope of previous models. MRAs also have a simple but realistic operational seman- tics that makes it straightforward to define concrete MRAs. Moreover, the definitions of policies and enforcement with MRAs are significantly simpler and more expressive than those of previous models. Putting all these features together, we argue that MRAs make good general models of (synchronous) runtime mechanisms, upon which a theory of run- time enforcement can be based. We develop some enforceability theory by characterizing the policies deterministic and nondeterministic MRAs enforce.

There is a vast deposit of viscous and heavy oil, especially in Canada and Venezuela. Typically thermal methods are used to recover heavy oil. However, thermal methods are inefficient when the depth of the reservoir is high and pay thickness is low. Non-thermal methods need to be developed for viscous and heavy oils. Alkaline-surfactant-polymer (ASP) floods can be used for improving the displacement efficiency, but its effect on sweep efficiency in viscous oil recovery has not been studied. The objective of this research was to investigate 2D ASP floods in a quarter five-spot pattern. Through careful phase behavior screening, the surfactant formulation was developed that produced ultra-low interfacial tension with reservoir viscous oil (100 cp). After verifying that the design of surfactant formulation was robust and can recover more than 90% of oil in a 1D ASP sandpack flood, it was tested in a 2D geometry. Both stable and unstable tertiary ASP floods were performed in a 2D quarter five-spot sandpack using the surfactant formulation developed in 1D ASP sandpack flood. In a stable ASP quarter five-spot sandpack flood, the oil recovery was excellent (~97% of ROIP). Oil recovery in the stable 2D ASP flood behaved similar to oil recovery in the 1D stable ASP flood. However, pressure drop obtained was high which would be unsustainable in field applications. Interestingly, unstable 2D flood performed well even with an adverse mobility ratio between oil/water bank and ASP slug with a recovery of 80% ROIP. Decreasing the viscosity of ASP slug 6 times decreased the maximum pressure drop 5 times; thus, the maximum pressure drop was almost proportional to the ASP slug viscosity in a 2D pattern. This research showed that unstable ASP flood in a 2D geometry can recover significant amount of oil with a practical pressure gradient. / text

There are numerous connections between the theory of formal languages and that of symbolic dynamics. In each, the transition from one dimension to two dimensionsis accompanied by much difficulty due in large part to the emptiness problem, which is related to the presence (or lack thereof) of periodic points and is known to be undecidable. Here, we focus on two-dimensional languages that have the property that all blocks allowed by the language can be extended to a configuration of the plane satisfying the structure of the language; for such languages the emptiness problem is not an issue. We first show that dot systems may be associated with two-dimensional languages having this property, so that we might employ these languages as varied examples. We next define a new type of finite automaton and with it, a tool for recognizing two-dimensional "strings" of data. It is then shown that these automata correctly represent the sofic shift spaces that result from the application of block maps to shifts of finite type. Thereafter, these automataare utilized to investigate properties of transitivity in the two-dimensional languages that they represent. More specifically, new definitions for different types of two-dimensional transitivity are adapted from topological dynamics and then illustrated through the use of dot systems. The appearance of periodic points in the languages represented by these automata is also explored, with a main result being that the existence of a periodic pointis guaranteed under certain conditions. Finally, issues of equivalence are introduced in the two-dimensional setting with regards to formal languages (syntactic monoids) and symbolic dynamics (the follower sets of a graph representing a sofic shift space).

<p>Spin-imbalanced Fermi gases serve as a testbed for fundamental notions and are efficient table-top emulators of a variety of quantum matter ranging from neutron stars, the quark-gluon plasma, to high critical temperature superconductors. A macroscopic quantum phenomenon which occurs in spin-imbalanced Fermi gases is that of phase separation; in three dimensions, a spin-balanced, fully-paired superfluid core is surrounded by an imbalanced normal-fluid shell, followed by a fully polarized shell. In one-dimension, the behavior is reversed; a balanced phase appears outside a spin-imbalanced core. This thesis details the first density profile measurements and studies on spin-imbalanced quasi-2D Fermi gases, accomplished with high-resolution, rapid sequential spin-imaging. The measured cloud radii and central densities are in disagreement with mean-field Bardeen-Cooper-Schrieffer theory for a 2D system. Data for normal-fluid mixtures are well fit by a simple 2D polaron model of the free energy. Not predicted by the model is an observed phase transition to a spin-balanced central core above a critical polarization.</p> / Dissertation