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Network Formation of Polyether-diisocyanate with Anionic Catalystt

Nobuyoshi SASAKI, Tetsuo MORI, Yukio YAMAGUCHI, Tetsuo YOKOYAMA, Takehide TANAKA
1972 NIPPON KAGAKU KAISHI  
doi:10.1246/nikkashi.1972.413 fatcat:v22dopuubrfotpzbyt3ttlthja

Analyzing Trade-offs in Reversible Linear and Binary Search Algorithms [article]

Hiroki Masuda, Tetsuo Yokoyama
2019 arXiv   pre-print
Reversible algorithms are algorithms in which each step represents a partial injective function; they are useful for performance optimization in reversible systems. In this study, using Janus, a reversible imperative high-level programming language, we have developed reversible linear and binary search algorithms. We have analyzed the non-trivial space-time trade-offs between them, focusing on the memory usage disregarding original inputs and outputs, the size of the output garbage disregarding
more » ... arbage disregarding the original inputs, and the maximum amount of traversal of the input. The programs in this study can easily be adapted to other reversible programming languages. Our analysis reveals that the change of the output data and/or the data structure affects the design of efficient reversible algorithms. For example, the number of input data traversals depends on whether the search has succeeded or failed, while it expectedly never changes in corresponding irreversible linear and binary searches. Our observations indicate the importance of the selection of data structures and what is regarded as the output with the aim of the reversible algorithm design.
arXiv:1910.10406v1 fatcat:cbwr4mt7qvcvzb73cxdnqnkqqq

Deterministic second-order patterns

Tetsuo Yokoyama, Zhenjiang Hu, Masato Takeichi
2004 Information Processing Letters  
Second-order patterns, together with second-order matching, enable concise specification of program transformation, and have been implemented in several program transformation systems. However, second-order matching in general is nondeterministic, and the matching algorithm is so expensive that the matching is NP-complete. It is orthodox to impose constraints on the form of higher-order patterns so as to obtain the desirable matches satisfying certain properties such as decidability and
more » ... ability and finiteness. In the context of unification, Miller's higher-order patterns have a single most-general unifier. In this paper, we relax the restriction of his patterns without changing determinism in the context of matching instead of unification. As a consequence, our deterministic second-order patterns cover a wide class of useful patterns for program transformation. The time-complexity of our deterministic matching algorithm is linear in the size of a term for a fixed pattern.
doi:10.1016/j.ipl.2003.12.008 fatcat:6rqesghd5jcjhnekqejadgkyey

Reversible Computing: Foundations and Software

Robert Glück, Tetsuo Yokoyama
2018 New generation computing  
Reversible computing is an emerging field of computer science that has received increasing attention during the past years. The articles in this special issue reflect the broad spectrum of research on reversible computing, including topics such as programming languages and semantics, methods and algorithms, computation models and theoretical foundations. Reversible computing has derived from fundamental questions on inverting programs and computations. Inverse problems arise frequently in
more » ... frequently in mathematics, science and engineering, but the corresponding problems in computer science are yet to be fully understood. This special issue aims at contributing to this long-term endeavor by providing a forum in which answers to important questions are presented in detail. The fully reviewed articles in this special issue are arranged alphabetically and represent the latest research on topics ranging from theoretical investigations to practical studies and applications. Here is a brief summary of the six articles. Jarkko Kari [1] surveys results of and recent developments in research on reversible cellular automata, a massively parallel computation model. The article presents techniques to construct reversible cellular automata and discusses undecidability issues and types of universality. Kazutaka Matsuda and Meng Wang [2] tackle the classic problem of constructing parsers using grammar-based inversion as well as program composition and specialization techniques for generating efficient parsers for context-free languages from unparsers, also known as pretty printers. Torben AEgidius Mogensen [3] investigates dynamic memory management, a central system component for supporting dynamic data structures and pattern matching in reversible functional programming languages, and experimentally evaluates a heap manager algorithm for a reversible intermediate language.
doi:10.1007/s00354-018-0035-5 fatcat:cblgwa6ffba6dbyx7kg7opztbm

The Glass Transition of Aliphatic Ionenes

Adi Eisenberg, Hiroshi Matsuura, Tetsuo Yokoyama
1971 Polymer journal  
The glass-transition temperatures of a wide range of ionenes have been studied as a function of the spacing of ions and the dielectric constant of the plasticizer. For solvents of a high dielectric constant the extrapolated glass transition of most ionenes has a value of ca. 0°C, while for plasticizers of a low dielectric constant the value centers around -80°C. It is suggested that a conformational transition is responsible for this drastic change in the extrapolated T0 values. A qla effect
more » ... es. A qla effect was also found, the slope of the T0 vs. qla plot being 695, i.e., quite similar to that for the phosphates, silicates, and acrylates.
doi:10.1295/polymj.2.117 fatcat:voweu4ckebcwhlu7lifdcycdgi

Post-traumatic Pituitary Apoplexy

Haruaki UCHIYAMA, Shigeru NISHIZAWA, Akihiko SATOH, Tetsuo YOKOYAMA, Kenichi UEMURA
1999 Neurologia medico-chirurgica  
A 60-year-old female and a 66-year-old male presented with post-traumatic pituitary apoplexy associated with clinically asymptomatic pituitary macroadenoma manifesting as severe visual disturbance that had not developed immediately after the head injury. Skull radiography showed a unilateral linear occipital fracture. Magnetic resonance imaging revealed pituitary tumor with dumbbell-shaped suprasellar extension and fresh intratumoral hemorrhage. Transsphenoidal surgery was performed in the
more » ... rformed in the first patient, and the visual disturbance subsided. Decompressive craniectomy was performed in the second patient to treat brain contusion and part of the tumor was removed to decompress the optic nerves. The mechanism of post-traumatic pituitary apoplexy may occur as follows. The intrasellar part of the tumor is fixed by the bony structure forming the sella, and the suprasellar part is free to move, so a rotational force acting on the occipital region on one side will create a shearing strain between the intra-and suprasellar part of the tumor, resulting in pituitary apoplexy. Recovery of visual function, no matter how severely impaired, can be expected if an emergency operation is performed to decompress the optic nerves. Transsphenoidal surgery is the most advantageous procedure, as even partial removal of the tumor may be adequate to decompress the optic nerves in the acute stage. Staged transsphenoidal surgery is indicated to achieve total removal later.
doi:10.2176/nmc.39.36 pmid:10093459 fatcat:76oiok6ifnhvfasqztr7yauhwq

A Case of Maxillary Neurofibroma

Yukisato Kitamura, Michiaki Yokoyama, Tetsuo Yamamoto, Kiyoshi Inaga
1985 Practica Oto-Rhino-Laryngologica  
上 顎 洞 に 発 生 し たNeurofibromaの1例 北 村 幸 郷 ・横 山 道 明 山 本 哲 夫 ・稲 賀 潔 A Case of Maxillary Neurofibroma Yukisato Kitamura, Michiaki Yokoyama, Tetsuo Yamamoto and Kiyoshi Inaga (Tottori University) A case of maxillary  ... 
doi:10.5631/jibirin.78.8special2_1847 fatcat:v5uhcqa4k5dspgfb3ovianfxle

Reversible Computation and Reversible Programming Languages

Tetsuo Yokoyama
2010 Electronical Notes in Theoretical Computer Science  
Yokoyama / Electronic Notes in Theoretical Computer Science 253 (2010) 71-81 The swap operator x1 <=> x2 is syntactic sugar for the statement sequence x1^= x2; x2^= x1; x1^= x2. 4 Some of the original  ... 
doi:10.1016/j.entcs.2010.02.007 fatcat:jkfz6vwpnncttkhnudpl4r6ze4

Program Optimizations and Transformations in Calculation Form [chapter]

Zhenjiang Hu, Tetsuo Yokoyama, Masato Takeichi
2006 Lecture Notes in Computer Science  
The world of program optimization and transformation takes on a new fascination when viewed through the lens of program calculation. Unlike the traditional fold/unfold approach to program transformation on arbitrary programs, the calculational approach imposes restrictions on program structures, resulting in some suitable calculational forms such as homomorphisms and mutumorphisms that enjoy a collection of generic algebraic laws for program manipulation. In this tutorial, we will explain the
more » ... will explain the basic idea of program calculation, demonstrate that many program optimizations and transformations, such as the optimization technique known as loop fusion and the parallelization transformation, can be concisely reformalized in calculational form, and show that program transformation in calculational forms is of higher modularity and more suitable for efficient implementation.
doi:10.1007/11877028_5 fatcat:yg2ftladibbstbmu4jhzwfts2a

Cerebellar Ganglioglioma

Shigeru NISHIZAWA, Tetsuo YOKOYAMA, Hiroshi RYU, Toshiaki NINCHOJI, Ichiro SHIMOYAMA, Kengo SATOH, Seiji YAMAMOTO, Kenichi UEMURA
1991 Neurologia medico-chirurgica  
A 14-year-old boy presented with cerebellar ganglioglioma manifesting as severe headache and confu sion. Computed tomographic scans showed a huge, partly enhanced cystic cerebellar tumor. The tumor was totally removed. Histological examination disclosed glial cells and mature ganglion cells. The latter were identified by Nissl's staining and immunostaining for neurofilaments. Ganglion cells were present in the cerebellum and the surrounding subarachnoid space. This heterotopic growth of
more » ... c growth of ganglion cells enabled a firm diagnosis of cerebellar ganglioglioma.
doi:10.2176/nmc.31.777 pmid:1726226 fatcat:da2sy3mkefe5bhuxrzjxbad36a

Deterministic Higher-Order Patterns for Program Transformation [chapter]

Tetsuo Yokoyama, Zhenjiang Hu, Masato Takeichi
2004 Lecture Notes in Computer Science  
Higher-order patterns, together with higher-order matching, enable concise specification of program transformation, and have been implemented in several program transformation systems. However, higherorder matching generally generates nondeterministic matches, and the matching algorithm is so expensive that even second-order matching is NP-complete. It is orthodox to impose constraint on the form of patterns so as to obtain the desirable matches satisfying certain properties such as
more » ... such as decidability and finiteness. In the context of unification, Miller's higher-order patterns have a single most general unifier. We relax the restriction of his patterns without changing determinism in the context of matching instead of unification. As a consequence, our deterministic higher-order pattern (DHP) covers a wide class of useful patterns for program transformation. Our deterministic matching algorithm is efficient which is linear in the size of the term for a fixed pattern.
doi:10.1007/978-3-540-25938-1_12 fatcat:4rulvvmx65dnpfu52o3mfsqnp4

Development of Polyurethane/Chitin Composites
ポリウレタン/キチン系複合材料の開発

Kyoko HIRAOKA, Tetsuo YOKOYAMA
1997 NIPPON GOMU KYOKAISHI  
A novel functional composite by combining chitin and polyurethane elastomers was developed. Diisocyanates were reacted with polymer glycols at 80°C in a nitrogen atmosphere to form NCO-terminated prepolymers. Various amounts of chitin powder were added to a prepolymer with catalyst and mixed thoroughly. Then the reaction mixtures were molded by a press at 70 -90°C for l 7 hr. After synthetic conditions were examined, it was found that the proper range of the amount of chitin, the optimum time,
more » ... the optimum time, temperature, and pressure required for pressure-molding were 60wt%, 4hr, 90°C, and 30MPa, respectively. After screening several polymer glycols and diisocyanates, poly(oxytetramethylene) glycol and hexamethylene diisocyanate were found to be suitable for compatibility with chitin. Swelling, thermal property, tensile property, SEM, and water sorption of polyurethane/chitin composites were measured. The composites were brittle, but the wet composites became elastomeric. The composites had good humid-breathing function.
doi:10.2324/gomu.70.155 fatcat:mpx6dptty5h75pxjqwvvayzcgq

A Minimalist's Reversible While Language

Robert GLÜCK, Tetsuo YOKOYAMA
2017 IEICE transactions on information and systems  
The paper presents a small reversible language R-CORE, a structured imperative programming language with symbolic tree-structured data (S-expressions). The language is reduced to the core of a reversible language, with a single command for reversibly updating the store, a single reversible control-flow operator, a limited number of variables, and data with a single atom and a single constructor. Despite its extreme simplicity, the language is reversibly universal, which means that it is as
more » ... that it is as powerful as any reversible language can be, while it is linear-time self-interpretable, and it allows reversible programming with dynamic data structures. The four-line program inverter for R-CORE is among the shortest existing program inverters, which demonstrates the conciseness of the language. The translator to R-CORE, which is used to show the formal properties of the language, is clean and modular, and it may serve as a model for related reversible translation problems. The goal is to provide a language that is sufficiently concise for theoretical investigations. Owing to its simplicity, the language may also be used for educational purposes. key words: reversible programming language, reversible self-interpreter, while language, translation, program inversion * Reversible Turing machines have a four-line inverter, e.g. [6] .
doi:10.1587/transinf.2016edp7274 fatcat:3ipg2pgkvvedlmugdpwkuouxxu

Synthesis and Properties of Polyurethane Elastomer Graded Spherulite Size

Takahiko Okazaki, Mutsuhisa Furukawa, Tetsuo Yokoyama
1997 Polymer journal  
Poly(oxytetramethylene)glycol (PTMG)-4,4' -diphenylmethane diisocyanate (MDl)-based polyurethane elastomer (PUE) was prepared by a mold with a temperature gradient. Effect of the temperature gradient on morphologies and mechanical properties were studied by DSC, polarizing microscopy, tensile test, micro-hardness test, friction test, and DIN abrasion test. The prepared PUE had graded super-structures. Spherulite sizes of the PUE depended significantly on the temperature gradient. Spherulite of
more » ... ent. Spherulite of PUE in contact with the mold at low temperature was significantly smaller and more dense than that contacting the mold at high temperature. Micro-hardness of the PUE linearly increased from low temperature mold side to the high temperature mold side. Friction coefficient of the surface contact with the low temperature mold plate became more lowered compared to the surface in contact with the high temperature mold plate. Abrasion resistance of the surface in contact with the low temperature mold plate evaluated by DIN abrasion test were better than that at the high temperature mold plate. KEY WORDS Polyurethane Elastomer / Temperature Gradient / Graded Micro-domain Size / Graded Mechanical Property /
doi:10.1295/polymj.29.617 fatcat:i5pgwcuybrhm7grre6g5kjp43m

Triphasic AVP Secretion in Encephalopathy

YUKIHIRO HASEGAWA, TOMONOBU HASEGAWA, TETSUO YOKOYAMA, SHINOBU KOTO, TOSHIRO NAGAI, HIDEO CHO, YUTAKA TSUCHIYA
1990 Endocrinologia Japonica  
A patient with encephalopathy developed triphasic changes in the clinical course, starting with diabetes insipidus (DI), then the syndrome of inappropriate ADH secretion (SIADH), and followed by the final phase of DI. The clinical course of encephalopathy was very rapid. The patient lost consciousness completely within only one day after the onset. During the early phase, he lapsed into a condition of "brain death". We could not identify the etiology of the encephalopathy. The triphasic change
more » ... e triphasic change referred to above is similar to previous reports of cats model after stereotactic destruction of the supraopticohypophyseal tract. We speculate that our case may have been associated with neurohypophyseal dysfunction caused by supraopticohypophyseal tract damage.
doi:10.1507/endocrj1954.37.171 pmid:2226336 fatcat:kt7c2bezqvethblj3iswdusbai
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