Some Problems on Quenched Steels. III : On the Mechanism of Temper Hardening in Some Quenched Special Steels

The mechanism of temper hardening in Mn-steels and high C-Cr-steel was investigated by means of hardness, dilatometric and microscopic observations. When the retained austenite was tempered, carbides were precipitated from it, and the precipitation could be observed as the contraction in dilatometic curves and be conformed directly by microscopic analysis. The precipitation of carbide played an important role in the hardening, independent of Ar" transformation. The γ-α transformation of retained austenite took place after some amount of carbide had been precipitated

Microstructural Approach to Legume Seeds for Food Uses

This review summarizes the microstructures of several seed legumes based on previous work and some new findings. Fifteen species of tropically grown legumes , adzuki bean and soybeans (a leading variety and two local va rietie s) were examined by light and transmission electron microscopy in relation to food uses. Processing of adzuki beans to form Q!l bean paste is dis cussed to illustrate the effects of processing on microstructure of starch g rains. Differences in contents, shape and size of starch grains are emphasized in a comparison of soybeans wi th other legumes

バイリンガル ヒタイショウ モデル ノ ニホンゴ エ テキヨウ カンジ カラ エイゴ エノ ホンヤク ト カナ カラ エイゴ エノ ホンヤク トノ アイダ ノ カイリ

This study addresses two questions: the first question is about whether backward translation (i.e. the second language to the first language or L2-to-L1) exploits a different mental process from forward translation (i.e. the first language to the second language or L1-to-L2). A qualitatively difference has been proposed by Kroll and Stewart\u27s (1994) asymmetry model of bilingual memory representation: forward translation is largely conceptually mediated whereas backward translation is largely lexically mediated. Thus, the model predicts that backward translation will be faster than forward translation and also both L1 and L2 picture naming. We have examined this hypothesis using Japanese learners of English, who have rarely been taken up so far in the research of the bilingual memory. Our results of the backward translation task by Japanese-English bilinguals show that backward translation is conceptually mediated like forward translation, a contradicting result to Kroll and Stewart\u27s model. The second question is how kanji (Japanese logographic script) will be processed in the forward translation, i.e., whether kanji script accesses L1 lexicon (the set of L1 phonological labels) through or without phonological mediation. Our experiments show that kanji in the first encounter is most likely processed via phonological mediation. Thus we have obtained decisive evidence regarding the phonological-mediation controversy in the area of kanji recognition.　Keywords： asymmetry model, forward translation, backward translatio

Routine Method of 77Kr Production

開始ページ、終了ページ: 冊子体のページ付

Relation between Mental Health Status and Psychosocial Stressors among Pregnant and Puerperium Women in Japan: From the Perspective of Working Status

Mental health problems during pregnancy and postpartum periods are one of the alarming health issues among women in Japan. This study analyzed data on the Japanese version of the Kessler 6 (K6), specific psychosocial stressors, and working status of pregnant and puerperium women (n=1126) from respondents in the Comprehensive Survey of People’s Living Conditions (CSPLC) conducted in 2007 by Ministry of Health, Labour and Welfare in Japan. Multiple logistic analyses showed the significant associations between mental health and psychosocial stressors: “family relationship,” “pregnancy and birth,” and “incomes/ family budgets/ debts”, regardless of “employed” or “unemployed”. After stratified by working status, whereas “one’s job” stressor had an association with mental health only for employed females, stressors for “one’s disease/long -term care” and “housework” had associations only for unemployed ones. For employed women, the primary factor for mental health was “family relationship” stressor. Although mental health status measured by K6 was not different between employed or unemployed female population, primary stressors related mental health was revealed to differ with working status. Especially, “family relationship” stressor was the highest risk factor of mental health in employed women. More importantly, the results provided evidence on the differences in associations between mental health and specific psychosocial stressors by working status. Psychosocial risk assessments and interventions on working status among pregnant and puerperium women should be imperative to pay attention for social politics.DOI: http://dx.doi.org/10.11591/ijphs.v1i2.80

Some Problems on Quenched Steels. II : On the Mechanism of Temper Hardening in Quenched High Speed Steel

The cause of the secondary hardening in a quenched high speed steel was studied by measuring dilatation, high temperature hardness and electric resistance, and the following conclusions were obtained : (1) The cause of the decrease in hardness by tempering at the temperature 100～350° is the relief of the internal stresses induced by the structural change during quenching. (2) The secondary hardening is due to the precipitation of a special carbide from the residual austenite, and the martensitization of the residual austenite give the phenomenon a small effect

Non-Preemptive Scheduling on Machines with Setup Times

Consider the problem in which n jobs that are classified into k types are to be scheduled on m identical machines without preemption. A machine requires a proper setup taking s time units before processing jobs of a given type. The objective is to minimize the makespan of the resulting schedule. We design and analyze an approximation algorithm that runs in time polynomial in n, m and k and computes a solution with an approximation factor that can be made arbitrarily close to 3/2.Comment: A conference version of this paper has been accepted for publication in the proceedings of the 14th Algorithms and Data Structures Symposium (WADS

The vertex leafage of chordal graphs

Every chordal graph $G$ can be represented as the intersection graph of a collection of subtrees of a host tree, a so-called {\em tree model} of $G$. The leafage $\ell(G)$ of a connected chordal graph $G$ is the minimum number of leaves of the host tree of a tree model of $G$. The vertex leafage \vl(G) is the smallest number $k$ such that there exists a tree model of $G$ in which every subtree has at most $k$ leaves. The leafage is a polynomially computable parameter by the result of \cite{esa}. In this contribution, we study the vertex leafage. We prove for every fixed $k\geq 3$ that deciding whether the vertex leafage of a given chordal graph is at most $k$ is NP-complete by proving a stronger result, namely that the problem is NP-complete on split graphs with vertex leafage of at most $k+1$. On the other hand, for chordal graphs of leafage at most $\ell$, we show that the vertex leafage can be calculated in time $n^{O(\ell)}$. Finally, we prove that there exists a tree model that realizes both the leafage and the vertex leafage of $G$. Notably, for every path graph $G$, there exists a path model with $\ell(G)$ leaves in the host tree and it can be computed in $O(n^3)$ time