• Journal of the Earthquake Engineering Society of Korea
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• v.3 no.3
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• pp.63-74
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• 1999

A sliding mode fuzzy control (SMFC) algorithm is presented for vibration of large structures. Rule-base of the fuzzy inference engine is constructed based on the sliding mode control, which is one of the nonlinear control algorithms. Fuzziness of the controller makes the control system robust against the uncertainties in the system parameters and the input excitation. Non-linearity of the control rule makes the controller more effective than linear controllers. Design procedure based on the present fuzzy control is more convenient than those of the conventional algorithms based on complex mathematical analysis, such as linear quadratic regulator and sliding mode control(SMC). Robustness of presented controller is illustrated by examining the loop transfer function. For verification of the present algorithm, a numerical study is carried out on the benchmark problem initiated by the ASCE Committee on Structural Control. To achieve a high level of realism, various aspects are considered such as actuator-structure interaction, modeling error, sensor noise, actuator time delay, precision of the A/D and D/A converters, magnitude of control force, and order of control model. Performance of the SMFC is examined in comparison with those of other control algorithms such as $H_{mixed 2/{\infty}}$ optimal polynomial control, neural networks control, and SMC, which were reported by other researchers. The results indicate that the present SMFC is an efficient and attractive control method, since the vibration responses of the structure can be reduced very effectively and the design procedure is simple and convenient.

• Journal of Korean Academy of Nursing
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• v.5 no.1
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• pp.17-30
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• 1975

The concept and definition of nursing and her role have been changing in accordance with the socio-cultural factors of the initial society. At present, nursing is conceptualized as a health care profession assisting man to restore, maintain and promote health by providing knowledge, wilt strength and resources through various processes of interaction. Man′s behavior, of individual and group activities for health inclusive, is driven by the initial man′s value orientation. The purpose of this study is to investigate the value orientation regarding health of rural health center milieu in order to give data for; 1. the planning for the delivery of community nursing service, 2. the health education plan at all level of nursing care activities, and 3. the planning of curriculum for nursing education. A hundred opinion leaders among the labor population residing in rural areas (P-group), hundred and six professional nurses at rural health centers (N-group) were indirectly interviewed through questionaries. And ninety five of N-group were interviewed likewise of their perceptions of P-group (NP-group) from July 15, to October 15, 1974. The result is as follows: 1. Maintenance of health is revealed to be the most valued component for man′s happiness in all the three groups. (P-group: 7.30 S. D.=1.31), (N-group :7.84 S. D. =49), and (NP-group : 5.93 S. D. =2.28) 2. The average value score of the maintenance of health revealed significant difference by P〈.001 level between each of the three groups. (Between N-group and P-group : T= -4.07 P and NP ; T=-6.93, N and NP: T=-9.35) 3. Basic health maintenance activities necessary for maintenance and promotion of personal health were moderately valued by all the three groups, P-group ; 3.74 (S. D. =.43) , N-group: 3.52 (S. D. =.34), NP-group: 3.07 (S. D. :.55) Among the 8 categories of basic health maintenance activities, "food intake" was highly valued by P-group (mean value score; 4.00 S. D=.51) , "exercise and rest" and "personal cleanliness" was highly valued by both P-group (4.02, 4.08) and N-group (4.08, 4.22). 4. The mean value score of basic health maintenance activities revealed significant difference by P〈.001 level between each of the three groups (between P-group and N-group: T=-4, 07, N-and NP: T=-6.93, P and NP T=-9.35) 5. Among the 30 questionaries, dynamic activities for health maintenance were more valued in comparison to passive activities in an tile three groups. 6. In N-group, correlation between the value of basic health maintenance activities and the personal health status personal revealed moderate significance. Correlation between the value of basic health maintenance activities and the age revealed low significance. 7. In group, correlation between the value of basic health maintenance activities and; perception of personal health status revealed non significance, between the age and sex revealed low sign affiance, and between the educational status revealed moderate significance. Recommendations are as follows ; 1. The efforts towards alteration of value orientation concerning health in general in community nursing practice de focussed be that of family Planning. 2. In order to prepare professional nurses competent in understanding individual and group, social science and behavioral science be strength ended in planning nursing curriculum. 3. Milieu of nursing experience during nursing education be Planned to begin at simple nursing problem and move towards complex, f. e. home care towards health crisis situation in order to achieve dynamic role mastery.

• Clean Technology
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• v.22 no.1
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• pp.35-44
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• 2016

In this study, a computational chemistry methodology called as molecular modeling was been applied to explain several experiment results mechanistically. The reaction chosen for this study was to remove carbon dioxide, known as a primary greenhouse gas, by an epoxide via the carbon dioxide fixation to produce carbonates. This reaction inherently needs the use of catalysts because it has a significantly high activation barrier (55~59 kcal/mol). Among various types of catalysts, we studied in zeolitic imidazolate framework 90 (ZIF-90)/ionic liquid immobilized ZIF-90 (IL-ZIF-90), polystyrene-supported quaternized ammonium salt, KI/KI-glycine, and dimethylethanolamine (DMEA). First, probable reaction pathways were proposed based on calculated energetics by computational chemistry. The energetics was then used for the thermodynamic interpretation on the activity of catalysts. In the case of ZIF-90/IL-ZIF-90 and KI/KI-glycine, IL-ZIF-90 and KI-glycine showed better yields compared to their counterparts. The calculation proposed interesting results that it is not from the lowering of activation energy but from the unstable intermediates of ZIF-90 and KI-glycine. For DMEA, the calculated activation energy was ~42 kcal/mol, much lower than that of the non-catalytic reaction. A possible reaction pathway was located to confirm the interaction between −NH group from ammonium and oxygen from epoxide for polystyrene-supported quaternized ammonium salt.

• Journal of the Korean Magnetics Society
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• v.23 no.5
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• pp.149-153
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• 2013

The electronic structures of $TCr_2O_4$ (T = Fe, Co, Ni) spinel oxides have been investigated by employing synchrotron radiation-based soft X ray absorption spectroscopy (XAS). The measured 2p XAS spectra of transition-metal ions reveal that Cr ions are trivalent ($Cr^{3+}$), and all the T (T = Fe, Co, Ni) ions are divalent ($Fe^{2+}$, $Co^{2+}$, $Ni^{2+}$). It is also found that most of T (T = Fe, Co, Ni) ions occupy the A sites under the tetrahedral symmetry, while Cr ions occupy mainly the B sites under the octahedral symmetry. These findings show that the structures of $TCr_2O_4$ (T = Fe, Co, Ni) are very close to the normal spinel structures. Based on these findings, it is expected that Jahn-Teller (JT) effects are important in $FeCr_2O_4$ and $NiCr_2O_4$. In contrast, $CoCr_2O_4$ maintains the cubic structure without having the JT distortion since both $Cr^{3+}$ and $Co^{2+}$ ions are non-JT ions. This work suggests that the antiferromagnetic interaction between $Cr^{3+}$ and $T^{2+}$ ions plays an important role in determining the magnetic properties of $TCr_2O_4$ (T = Fe, Co, Ni).

• Journal of the Korean Society for Library and Information Science
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• v.30 no.2
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• pp.167-188
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• 1996

The lack of an understanding of the characteristics and searching abilities of a specific user group in computer-based information systems in libraries hinders library and information science professionals in making the best decisions when designing, acquiring, and managing information systems. The objective of this study was to provide information on the characteristics and searching abilities of specific groups such as Korean college students & ones who study abroad, male & female, undergraduate & graduate students, etc. This study also has focused on the methods of loaming to use OPACs and non-user study. Questionnaire was administered to both Korean college students in the city of Taegu, Korea and students who study abroad in the state of Texas, US.A. 345 usable questionnaires were obtained and analyzed. These were analyzed using descriptive, inferential statistics, multiple correlation, and SPSS software. The. major findings of this study are: (1) There was a significant difference among specific student user groups except undergraduate and artiste-athlete students in the distribution of their knowledge about how to use OPACs: (2) There was a significant difference among specific groups in the means of their knowledge: (3) There was no significant difference among un. groups in the distribution of loaming method to use OPAC systems : (4) The correlation between the number of searching methods that the respondents knew in using OPACS and the amount of using computers (0.6635) is comparatively higher than my other correlation to the searching methods. Also, years of experience using computers, frequencies of computer use, and frequencies of OPAC use are comparatively higher than frequencies of library use and frequencies of manual card catalog un: (5) Frequencies of manual card catalog use have low negative correlations with the number of searching methods that the respondents knew in using OPACs: (6) Frequencies of manual card catalog use have little if any negative negative with OPAC and computer use. Conclusions are drawn from the findings in this paper, and recommendations an proposed when designing, adopting, or managing a new system. Topics fur future studies on the characteristics of OPAC systems and their use are also suggested.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.10
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• pp.1550-1557
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• 2018

Objective: Circular RNAs (circRNAs) are a newfound class of non-coding RNA in animals and plants. Recent studies have revealed that circRNAs play important roles in cell proliferation, differentiation, autophagy and apoptosis during development. However, there are few reports about muscle development-related circRNAs in livestock. Methods: RNA sequencing analysis was employed to identify and annotate circRNAs from longissimus dorsi of sheep. Reverse transcription followed by real-time quantitative (q) polymerase chain reaction (PCR) analysis verified the presence of these circRNAs. Targetscan7.0 and miRanda were used to analyse the interaction of circRNA-microRNA (miRNA). To investigate the function of circRNAs, an experiment was conducted to perform enrichment analysis hosting genes of circRNAs using gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) pathways. Results: About 75.5 million sequences were obtained from RNA libraries of sheep skeletal muscle. These sequences were mapped to 729 genes in the sheep reference genome. We identified 886 circRNAs, including numerous circular intronic RNAs and exonic circRNAs. Reverse transcription PCR (RT-PCR) and DNA sequencing analysis confirmed the presence of several circRNAs. Real-Time RT-PCR analysis exhibited resistance of sheep circRNAs to RNase R digestion. We found that many circRNAs interacted with muscle-specific miRNAs involved in growth and development of muscle, especially circ776. The GO and KEGG enrichment analysis showed that hosting genes of circRNAs was involved in muscle cell development and signaling pathway. Conclusion: The study provides comprehensive expression profiles of circRNAs in sheep skeletal muscle. Our study offers a large number of circRNAs to facilitate a better understanding of their roles in muscle growth. Meanwhile, we suggested that circ776 could be analyzed in future study.

• Journal of the Korean Applied Science and Technology
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• v.14 no.1
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• pp.61-76
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• 1997

Triacylglycerols of the seeds of Ginkgo biloba have been resolved by high-performace liquid chromatography(HPLC} in the silver-ion and reverse-phase modes. The fatty acids were identified by a combination of capillary gas chromatography and gas-chromatography /mass spectrometry as the methyl and /or picolinyl ester. The main components are $C_{18:2{\omega}6}$(39.0mol%), $C_{18:1{\omega}7}$(asclepic acid 21.5mol%), and $C_{18:1{\omega}9}$(oleic acid, 13.8mol%). Considerable amounts of unusual acid such as $C_{20:3{\Delta}^{5,11,14}$ (5.7mol%), $C_{18:2{\Delta}^{5,9}$(2.8mol%), and $C_{18:3}{\Delta}^{5,9,12}$(1.6mol%), were checked. In addition, an anteiso-branched fatty acid, 14-methylhexadecanoic acid, was also present as a minor component(0.9 mol%). The triacylglycerols were separated into 17 fractions by reverse-phase HPLC, and the fractionation was achieved according to the partition numnber(PN) in which a ${\Delta}^5$-non methylene interrupted double bond($^5$-NMDB) showed different behaviour from a methylene interrupted double bond in a molecule with a given cahinlength. Silver-ion HPLC exhibited excellent resolution in which fractions(23 fractions) were resolved on the basis of the number and configuration of double bonds. In this instance, the strength of interaction of a ${\Delta}^5$-NMDB system with silver ions seemed to be weaker than a methylene interrupted double bond system. The principal triacylglycerol species are as follows ; $(C_{18:2{\omega}6)2}/C_{18:1{\omega}7}$, $C_{18:1{\omega}9}/C_{18:1{\omega}7}/C_{18:2{\omega}6}$, $(C_{18:1{\omega}7)2}/C_{18:2{\omega}6}$, $C_{16:1{\omega}7}/C_{18:1{\omega}9}/C_{20:3}{\Delta}^{5,11,14}$, $C_{16:1{\omega}7}/C_{18:1{\omega}7}/C_{20:3}{\Delta}^{5,11,14}$, $C_{18:1{\omega}9}/C_{18:1{\omega}7}/C_{18:2{\omega}6}$, $C_{18:1{\omega}9}/C_{18:2}{\Delta}^{5,5}/C_{20:3}{\Delta}^{5,11,14}$, $(C_{18:1{\omega}7)2}/C_{18:2{\omega}6}$ and $(C_{18:1{\omega}9)2}/C_{18:2{\omega}6}$, while simple triacylglycerols without $C_{18:2{\omega}6})_3$ were not present. Stereospecific analysis showed that fatty acids with ${\Delta}^5$-NMDB system and saturated chains were predominantly located at the site of sn-3 carbon of glycerol backbones. It is evident that there is asymmetry in the distribution of fatty acids in the TG molecules of Ginkgo nut oils.

• The Journal of the Korea Contents Association
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• v.20 no.2
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• pp.581-593
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• 2020

The purpose of this study was to examine the eye-fixation times on different parts of a student avatar and the virtual presence with two scenarios in the virtual reality-based teaching simulation. This study was to identify user attention while he or she is interacting with a student avatar. By examining where a user is gazing during a conversation with the avatar, we have a better understanding of non-verbal communication. For this study, forty-five college students (21 females and 24 males) participated in the experiment. They had a conversation with a student avatar in a virtual reality-based teaching simulation. The participants had verbal interactions with the student avatar with two scenarios. While they were having a conversation with the virtual character in the teaching simulation, their eye-movements were collected through a head-mounted display with an eye-tracking function embedded. The results revealed that there were significant differences in eye-fixation times. Participants gazed a longer time on facial expression than any other area. The fixation time on the facial expression was more prolonged than on gestures (F=3.75, p<.05). However, the virtual presence was not significantly different in two scenario levels. This result suggested that users focus on the face more than the gesture when they emotionally interact with the virtual character.

• Korean Journal of Cognitive Science
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• v.4 no.1
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• pp.51-86
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• 1993

The purpose of this study was to investigate on-line comprehension processing in pronoun resolution. The two important constraints investigated in this study were the gender cue of pronoun and the antecedent case. Using antecedent probe recognition task. Experiment 1 investigated the effects of gender cues and antecedent cases on probe recognition time. There were on signigicant effects of employed variable. This result suggest the possibilty of immediate antecedent assignment depending on the degree of syntactic constraints satisfaction. In Experiment 2. using antecedent probe recognition task. the primed activation level differences between antecedents and non-antecedents over time-course intervals from 0 to 250msec were measured. The effect of gender cues was obtained over 0-250msec time-course condition. This indicates that the gender cues can determine the assignment of proper antecedent for a pronoun. In Experiment 3, subect-case pronouns were used only:Unambiguous gender cues were given and the time-course intervals of 250 and 750msec were employed. A signigicant interaction effect of antecedent cases with probe conditions was obtained. All the results of this research suggest that gender cues are powerful constraints for pronoun resolution.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.3
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• pp.376-380
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• 2006

An experiment was conducted to study the effect of temperature and pH on in vitro nutrient degradability, volatile fatty acid profile and methane production. The fermenter used was the semi-continuous system, known as the rumen simulation technique (RUSITEC). Sixteen cylinders were used at one time with a volume of 800 ml, the dilution rate was set at 3.5%/hour, the infused buffer being McDougall's artificial saliva. Basal diet (9.6 g DM) used in RUSITEC consisted of (DM) 6.40 g Timothy hay, 1.86 g crushed corn and 1.34 g soybean meal. The food for the fermentation vessel was provided in nylon bags, which were gently agitated in the liquid phase. The experiment lasted for 17 d with all the samples taken during the last 5 d. Treatments were allocated at random to four vessels each and were (1) two temperature levels of $39^{\circ}C$ and $41^{\circ}C$ (2) two pH levels of 6.0 and 7.0. The total diet contained ($g\;kg^{-1}$ DM) 957 OM, 115 CP and $167MJ\;kg^{-1}$ (DM) GE. Although increase in temperature from $39^{\circ}C$ to $41^{\circ}C$ reduced degradation of major nutrients in vitro, it was non-significant. Interaction effect of temperature with pH also reflected a similar trend. However, pH showed a significant (p<0.05) negative effect on the degradability of all the nutrients in vitro. Altering the in vitro pH from 7 to 6 caused marked reduction in DMD from 60.2 to 41.8, CPD from 76.3 to 55.3 and GED from 55.3 to 35.1, respectively. Low pH (6) depressed total VFA production (61.9 vs. 34.9 mM) as well as acetate to propionate ratio in vitro (from 2.0 to 1.5) when compared to pH 7. Compared to pH 7, total gas production decreased from 1,841 ml to 1,148 ml at pH 6, $CO_2$ and $CH_4$ production also reduced from 639 to 260 ml and 138 to 45 ml, respectively. This study supported the premise that pH is one of the principal factors affecting the microbial production of volatile fatty acids and gas. Regulating the ruminal pH to increase bacterial activity may be one of the methods to optimize VFA production, reduce methane and, possibly, improve animal performance.