• JSTS:Journal of Semiconductor Technology and Science
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• v.16 no.1
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• pp.11-22
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• 2016

Clock skew scheduling is one of the essential steps to be carefully performed during the design process. This work addresses the clock skew optimization problem integrated with the consideration of the inter-dependent relation between the setup and hold times, and clock to-Q delay of flip-flops, so that the time margin is more accurately and reliably set aside over that of the previous methods, which have never taken the integrated problem into account. Precisely, based on an accurate flexible model of setup time, hold time, and clock-to-Q delay, we propose a stepwise clock skew scheduling technique in which at each iteration, the worst slack of setup and hold times is systematically and incrementally relaxed to maximally extend the time margin. The effectiveness of the proposed method is shown through experiments with benchmark circuits, demonstrating that our method relaxes the worst slack of circuits, so that the clock period ($T_{clk}$) is shortened by 4.2% on average, namely the clock speed is improved from 369 MHz~2.23 GHz to 385 MHz~2.33 GHz with no time violation. In addition, it reduces the total numbers of setup and hold time violations by 27.7%, 9.5%, and 6.7% when the clock periods are set to 95%, 90%, and 85% of the value of Tclk, respectively.

• The Journal of Korean Academic Society of Nursing Education
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• v.22 no.4
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• pp.419-429
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• 2016

Purpose: This study investigated the effects of father's occupational stress and rearing attitude on rearing participation. Methods: The participants of this study were 201 fathers who are raising children in J region. The data were collected by self-report using questionnaires from August to September, 2015. The data were analyzed using descriptive statistics. t-test, ANOVA, and Pearson correlation coefficient, Scheffe test, and stepwise multiple linear regression with the SPSS/WIN 21.0 program. Results: The total mean scores of occupational stress on the subjects were 40.98(${\pm}8.36$), rearing attitude were $68.54({\pm}7.18$), rearing participation were $73.16({\pm}11.34$). The study showed that occupational stress is negatively correlated with rearing participation and rearing attitude positively correlated with rearing participation. Working style and rearing attitude were identified of rearing participation. Conclusion: A father's rearing participation level was influenced by father's attitude of caring children above all. In addition, fathers' working styles were also a main factor. Therefore, it is necessary for fathers to learn rearing attitudes in a way that can develop a nursing intervention program to increase their rearing participation level.

• The Korean Journal of Community Living Science
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• v.15 no.2
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• pp.83-92
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• 2004

The purpose of this research is to determine the influence of affectionate child-rearing behavior on children's self esteem. The sample group was composed of 200 forth and sixth grade elementary school students. The statistics used for this data were frequency, percentile, averages, standard deviation, Cronbach's alpha, t-test, Pearson's correlation, and stepwise multiple regression analysis. The major findings of the research were as follows: First, the scores of affectionate child-rearing behavior(3.60), global self-worth(3.58), social acceptance(3.46) and behavior conduct(3.28) were higher than the mean scores. On the contrary the scores of cognitive ability(2.95), physical ability(2.94) and physical appearance(2.85) were lower than the mean scores. Second, there were significant differences in cognitive ability based on gender(p＜.01) and global self-worth based on grade(p<.05). Third, the influence of affectionate child-rearing behavior on children's self esteem was found to be significant due to the sub-areas of self-esteem. Affectionate child-rearing behavior affects all sub-areas of self-esteem. Affectionate child-rearing behavior affects cognitive ability(p<.001), physical ability(p＜.01), physical appearance(p＜.01), social acceptance(p＜.001), behavior conduct(p＜.01) and global self-worth(p＜.001). In addition, gender(p＜.01) affects cognitive ability and grade(p＜.05) affects global self-worth.

• Journal of Korean Academic Society of Home Health Care Nursing
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• v.19 no.2
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• pp.150-161
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• 2012

Purpose: This study was performed to investigate the influencing factors of cognitive function and depression in elderly. Method: From 3 provinces, 282 elders who resided in community and facilities completed structured questionnaires, including cognitive functions, depression, self-esteem, ADL, and IADL. Data were analyzed by applying ${\chi}^2$-test, ANOVA, partial correlation coefficient, and stepwise multiple regression analysis with SAS 8.12. Results: Community dwelling aged people showed higher scores in MMSE-K, self-esteem, ADL and IADL, and showed lower scores in depression than facility elders. MMSE-K was positively correlated in self-esteem, ADL, and personal cognition of health, except depression. Major factors that affect cognitive function of elderly were residual type, age, and IADL. In addition, major factors that affect depression of elderly were self-esteem, personal cognition of health, and marital status. Conclusions: Based on the results above, it is necessary to identify the status of cognition and depression in the elderly, and to develop nursing intervention programs, which improve cognitive function and reduce depression for aged, especially for the facility admitted aged.

• Journal of Families and Better Life
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• v.22 no.3
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• pp.63-74
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• 2004

The purpose of this study was to investigate the variables which account for college students' attitudes toward parent caregiving. The subjects or this research were 204 students(male:98, female:106) who were currently enrolled at three coeducational universities and one women's university located in the metropolitan area. The instruments used for this study were Attachment and Conflict Scale by Song(1986) and Im(1988), and Parent Caregiving Attitudes Scale by Shin(1993). The data were analyzed with descriptive statistics, t-test, Pearson's correlations and stepwise multiple regression. The major results of this study were as follows: First, it turned out that a significant gender difference in attitudes toward parent caregiving exists. Female college students had more positive attitudes toward parent caregiving than male college students. Second, the variables explaining college students'attitudes toward parent caregiving were the extent of attachment with their parents and the experience of cohabitation with their grandparents. The stronger male and female students had attachment with their parents, the more positive attitudes toward parent caregiving they had. In addition, male college students without an experience of cohabitation with their grandparents reported more positive attitudes toward parent caregiving.

• Economic and Environmental Geology
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• v.17 no.2
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• pp.141-147
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• 1984

For the discussion of palaeogeomagnetic field direction and the movement and rotation of geotectonic blocks it is prerequisite to eliminate the secondary remanent magnetization component out of the NRM vector of given rock samples. Among various techniques alternating field and thermal demagnetization methods are most easily applicable and most widely used ones. Physical principle underlying these methods is the concept of relaxation time: Either with an action of external magnetic field or with an elevated temperature relaxation time of magnetic minerals can be drastically shortened. It has been furthermore shown experimentally that the secondary remanent magnetization can be more easily demagnetized than the primary remanent magnetization. Through careful stepwise demagnetization it should also be possible to discriminate the kind of various remanent magnetizations. In addition to the introduction to the underlying physical principles and experimental results of the alternating field and thermal demagnetization this paper gives various practical tips in earring out the demagnetization experiments. Each alternating field and thermal demagnetization instrumentation which is easily adaptable to domestic palaeomagnetic laboratories is also introduced. This paper provides a compact and practical introduction to the methods in palaeomagnetism and would be of interest to present workers and to those who want to embark on research in this field.

• Journal of Marine Bioscience and Biotechnology
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• v.1 no.4
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• pp.311-316
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• 2006

Enzymatic ethanolysis of fish oil with immobilized lipase was investigated for reducing the free fatty acid contents and enhancing the function of fish oil. Ethanolysis reactions were carried out in erlenmeyer flask (25ml) containing a mixture of squid viscera oil and 99.9% ethanol using 1% (based on w/w squid viscera oil) immobilized lipase. The reaction mixtures were incubated at $50^{\circ}C$ and shaken at 100rpm. Ethanol was added into the mixture by stepwise addition method of Shinmada[9]. Measurement of free fatty acid molar amounts was studied by Acid Value. Tendency of oil variation during transesterification was studied by TLC method. Enzymatic ethanolysis composed diglyceride, monoglyceride and fatty acid ethyl ester with reducing free fatty acid contents. Also, selective ethanolysis by Lipozyme TL-IM and Lipozyme RM-IM mostly did not react at the sn-2 position of squid viscera oil. Lipozyme RM-IM was more suitable enzyme to reduce the free fatty acid contents by ethanolysis than Lipozyme TL-IM. Squid viscera oil was transformed into suitable properties (5 in Acid Value) for functional fish oil production.

• Bulletin of the Korean Chemical Society
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• v.28 no.8
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• pp.1341-1345
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• 2007

The surface chemistry of D2O dosed Zircaloy-4 (Zry-4) surface followed by Ar-ion bombardment and annealing was studied by means of X-ray photoelectron spectroscopy (XPS) and Ultraviolet photoelectron spectroscopy (UPS). In the XPS study, Ar-ion bombardment caused decrease of the oxygen on the surface region of Zry-4 and therefore led to change the oxidation states of the zirconium from oxide to metallic form. In addition, oxidation states of zirconium were changed to lower oxidation states of zirconium due to depopulation of oxygen on the surface region by annealing. Up to about 787 K, the bulk oxygen diffused out to the subsurface region and after this temperature, the oxygen on the surface of Zry-4 was depopulated. UPS study showed that the valence band spectrum of the D2O exposed Zry-4 exhibited a dominant peak at around 13 eV and no clear Fermi edge was detected. After stepwise Ar+ sputtering processes, the decrease of the oxygen on the surface of Zry-4 led to suppress the dominant peak around 13 eV, the peak around 9 eV and develop a new peak of the metallic Zr 4d state (20.5-21.0 eV) at the Fermi level.

• Physical Therapy Korea
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• v.22 no.4
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• pp.27-33
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• 2015

The purpose of this study was to find which spatiotemporal gait parameters gained from stroke patients could be predictive factors for the gait part of Tinetti Performance-Oriented Mobility Assessment (POMA-G). Two hundred forty-six stroke patients were recruited for this study. They participated in two assessments, the POMA-G and computerized spatiotemporal gait analysis. To analyze the relationship between the POMA-G and spatiotemporal parameters, we used Pearson's correlation coefficients. In addition, multiple linear regression analyses (stepwise method) were used to predict the spatiotemporal gait parameters that correlated most with the POMA-G. The results show that the gait velocity (r=.67, p<.01), cadence (r=.66, p<.01), step length of the affected side (r=.49, p<.01), step length of the non-affected side (r=.53, p<.01), swing percentage of the non-affected side (r=.47, p<.01), and single support percentage of the affected side (r=.53, p<.01) as well as the double support percentage of the non-affected side (r=-.42, p<.01) and the step-length asymmetry (r=-.64, p<.01) correlated with POMA-G. The gait velocity, step-length asymmetry, cadence, and single support percentage of the affected side explained 67%, 2%, 2%, and 1% of the variance in the POMA-G, respectively. In conclusion, gait velocity would be the most predictive factor for the POMA-G.

• Journal of Families and Better Life
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• v.29 no.1
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• pp.127-138
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• 2011

This study analyzed the internal-external controls, psychological well-being and depression of mothers as factors that affect mothers's parenting style of young children. The participants were 228 mothers of preschoolers. Data were analyzed by descriptive statistics, Pearson's productive correlation, and stepwise multiple regression analysis. Results showed that positive mothers parenting style had positive relationships with internal control and psychological well-being. On the other hand, positive mother's parenting style had negative relationships with external control and depression. In addition, negative mother's parenting style had positive relationships with external control and depression. On the other hand, negative mother's parenting style had no relationship with psychological well-being and internal control. Psycholobrical well-being had the strongest effect on positive mother's parenting style and external control had the strongest effect on negative mother's parenting.