• Korean Journal of Food Science and Technology
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• v.26 no.1
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• pp.88-92
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• 1994

The influence of the storage temperature between $0^{\circ}C$ and $30^{\circ}C$ on the biochemical, physical changes and meat qualities in the red muscle(M. sternomandibularis and M. mastoideus) of Korean native cattle postmortem were studied. The results obtained were summarized as follows; The pH-value during the first hours post mortem was dropped faster in storage temperature $0^{\circ}C$ than in $10^{\circ}C$, but the final pH-value reached after about 30 hrs. post mortem. The muscle which was stored in $30^{\circ}C$ reached the final pH within 10 hrs. The muscle which was stored in $0^{\circ}C$ showed the increased R-value at fast speed from the beginning. It reached maximum R-value after 20 hrs as it gradually increase showing low R-value by 10 hrs. in $10^{\circ}C$. The muscle which was stored in $0^{\circ}C$ shortened to about 46% after 10 hrs. It was contracted about 17% after 15 hrs in $10{\sim}20^{\circ}C$. The sarcomere length of Korean native cattle had the least contraction in $10^{\circ}C$ and it was contracted $18{\sim}20%\;(1.60{\sim}1.63\;{\mu}m)$ after 5 hrs., $45{\sim}46%$after 24 hrs in $0^{\circ}C$ and $30^{\circ}C$ which was generated cold shortening and rigor shortening. The meat that was stored in $0^{\circ}C$ and $30^{\circ}C$ showed about 2-fold higher shear force than it that was stored in $10^{\circ}C$ at postmortem 24 hrs. The meat that was stored in $10^{\circ}C$ at postmortem 24 hrs. showed drip loss less than 3% during the 9 days ripening period. The meat with cold shortening and rigor shortening showed the high drip loss.

• Journal of Animal Science and Technology
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• v.48 no.6
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• pp.921-932
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• 2006

Management to improve beef tenderness is always been a historical idea, but during the recent past it has become an issue of prime importance to the meat scientists and the industries as well. Variation in tenderness is the prime explanation for consumer’s dissatisfaction for the concern meat. It has been well documented that both postmortem proteolysis and sarcomere length have significant effect on meat tenderness and its consistency. Electrical stimulation and tenderstretch techniques have been used by a number of countries to underpin carcass quality assurance schemes focused on eating quality. The mechanism(s) by which the postmortem interventions improve tenderness (or prevent toughness) has not been fully elucidated. However, it is evident that electrical stimulation accelerates the development of rigor mortis so that prevention of cold shortening is possible and ageing commences at higher temperatures. On the other hand, tendersretch appears to prevent meat toughness via placing tension of the myofibrils and connective matrix during rigor development. Previous findings indicated that electrical stimulation and tenderstretch improved beef tenderness even for fattened cattle under moderate chilling conditions. Recent studies demonstrate beef tenderness to be one of the most important factors determining satisfaction levels of Korean beef consumers. There are number of studies which reported that electrical stimulation and tenderstretch techniques improved Hanwoo tenderness and color. It is believed that the techniques are mostly useful wherein controls of carcass size, fatness and/or chilling regimes are not easy such as Korean beef industry. However, Korean beef industry is one such area where postmortem intervention techniques have not been adopted so far. Taking into consideration of the Korean beef industry, wherein carcass size and fatness varies the post-slaughter intervention technique could be the most feasible measurement to ensure eating quality. The manuscript attempts to highlight the current knowledge aiming primarily towards the assurance of beef tenderness.

• Korean Journal of Food Science and Technology
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• v.25 no.1
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• pp.57-62
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• 1993

The influence of the storage temperature at $15^{\circ}C$ on the biochemical and structural changes in the red muscles (M. sternomandibularis) of korean native cattle postmortem were studied. The results obtained were summarized as follows; 1.5 to 2 hours postmortem the pH-value had dropped to $6.7{\sim}6.8$, after 18 or 20 hours at $15^{\circ}C$ it had reached its final pH-value (5.5). The irreversible loss of extensibility, i.e. the onset of rigor mortis, arose at $15^{\circ}C$ between 9 and 10 hours postmortem at pH 6.1 to 6.0 and R-value between 1.05/1.10. The complete loss of extensibility postmortem was reached after 18 to 20 hours at pH 5.5/5.6. Muscle and sarcomere length of korean native cattle were contracted about 20% and 15%, respectively at $15^{\circ}C$. Meat of korean native cattle had the highest shear force (4.7 kg) on 1 day after slaughter. The tenderness was increased with the ripening period prolonged and was highest at the end of the 9 day ripening period.

• Food Science of Animal Resources
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• v.23 no.2
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• pp.109-114
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• 2003

This study was conducted to investigate the effect of sarcomere length, carcass and quality traits on tenderness of Hanwoo beef at 24 hr postmortem. Immediately after slaughter, a total number of 30 carcasses(Hanwoo bull) selected, and sarcomere length was determined during rigor development(1, 3, 6, 12 and 24 hr). Tenderness group of longissimus dorsi muscle classified into tender group($\leq$7.5 kg/$\textrm{cm}^2$, n=9), or tough group($\geq$9.0 kg/$\textrm{cm}^2$, n=9) by shear force value at 24 hr postmortem, and estimated carcass traits, meat color, connective tissue and sensory property at 24 hr postmortem. Results showed that tender group had heavier carcass weight, thicker back fat, higher marbling score, lighter meat color, more white fat color and lower texture score(p<0.05). The change of sarcomere length was linearly decreased(p<0.05) from 3 hr postmortem, and the sarcomere length of tender group was significantly(p<0.05) longer than that of tough group at 3, 6 and 24 hr postmortem. The tender group showed significantly lower(p<0.05) shear force value of intramuscular connective tissue(IMCT), better(p<0.05) tenderness and overall acceptability compared to the tough group. Results indicated that tenderness of beef longissimus dorsi muscle could be improved by thicker back fat, higher marbling score and lower texture score, and predicted by sarcomere length of pre-rigor(3 and 6 hr postmortem). Also, the tenderness of beef longissimus dorsi muscle could be closely related to shear force value of IMCT, compared to total collagen and soluble collagen content in the same age.

• Food Science of Animal Resources
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• v.41 no.4
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• pp.650-663
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• 2021

The objective of this study was to examine the relationship between meat quality attributes and the changes of sarcoplasmic protein acetylation and myofibrillar protein acetylation in lamb longissimus thoracis et lumborum muscles at different postmortem phases. Protein acetylation, color, pH, shear force, myofibril fragmentation index and cooking loss were measured. The total level of acetylated sarcoplasmic proteins showed a negative relation with pH, a positive relation with a^*, b^* and cooking loss at the pre-rigor phase. Sarcoplasmic proteins acetylation affected postmortem pH by regulating glycolysis, which in turn affects color and cooking loss. The total level of acetylated myofibrillar proteins showed a positive relation with shear force at the pre-rigor phase. Myofibrillar proteins acetylation affected meat tenderness by regulating muscle contraction. This study indicated that acetylation played a regulatory role of meat color, water-holding capacity, and tenderization process at early postmortem.

• East Asian mathematical journal
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• v.31 no.4
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• pp.459-481
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• 2015

In this study, we investigated whether the theorem is established even if we replace a 'square' element in the Euclidean proof of the Pythagorean theorem with different figures. At this time, we used different figures as equilateral, isosceles triangle, (mutant) a right triangle, a rectangle, a parallelogram, and any similar figures. Pythagorean theorem implies a relationship between the three sides of a right triangle. However, the procedure of Euclidean proof is discussed in relation between the areas of the square, which each edge is the length of each side of a right triangle. In this study, according to the attached figures, we found that the Pythagorean theorem appears in the following three cases, that is, the relationship between the sides, the relationship between the areas, and one case that do not appear in the previous two cases directly. In addition, we recognized the efficiency of Euclidean proof attached the square. This proving activity requires a mathematical process, and a generalization of this process is a good material that can experience the diversity and rigor at the same time.

• The Journal of Korean Academic Society of Nursing Education
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• v.3 no.2
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• pp.246-254
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• 1997

Nursing have been caught between the paradigm of medical science with a body part view of a person and the paradigm of medical science with an emphasis on unsurpassable control, rigor, objectivism, and neutrality of value. But it is inappropriate to apply impersonal, objective model of science for the personal unique and gestalt experiences of nursing phenomena. Jean Watson proposed a theory of human caring based on human science paradigm to explain human phenomena. This study reviewed the theory of nursing by Jean Watson and the researches based on Waton's theory. In this study the researcher examined the philosophical back ground, value system and key concepts of Watson's theory Watson's perspective of person and human existence includes humanistic and phenomenological characteristics. She also emphasized nurse-patient relationship as an intersubjective(transpersonal) caring relationship. Examination of the studies based on Watson's theory consistantly revealed Watson's theory of human caring based on the human science paradigm is more appropriate than traditional medical science paradigm for explaining nursing phenomena. For the purpose of refining the theory and promoting usefulness of the theory, it would be desirable to test the theory to the nursing phenomena and to apply the theory to practice and education.

• Journal of Korean Academy of Nursing Administration
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• v.19 no.1
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• pp.63-75
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• 2013

Purpose: The goal of this study was to identify the current status of research on job stress conducted in Korea and to suggest directions for future nursing research. Methods: A total of 395 articles (76 nursing science, 100 health science, 219 social science) selected from 'Korean Research Foundation Registered Journals' were reviewed. The papers were classified by criteria, focusing on research frameworks, topics and methodologies. Results: There has been a rapid increase in the number of articles since the 1990s. However, the following issues were discovered: lack of theoretical frameworks about factors related to job stress, a paucity of attention to sophisticated methodologies including the development of strong measurement tools, and incoherence among the level of theory, level of measurement, and/or level of statistical analysis. Conclusion: Based on the key findings of this study the following are proposed: increased efforts to develop theoretical framework to guide empirical investigations, improvements in methodological rigor, research conduct with various job groups with different approaches such as qualitative or experimental research, and encouragement for interdisciplinary approaches to the study on job stress.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2004.04a
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• pp.111-114
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• 2004

Management of human knowledge is an interesting concept that has attracted the attention of philosophers for thousands of years. Artificial intelligence and knowledge engineering has provided some degree of rigor to the study of knowledge systems and expert systems(ES) re able to use knowledge to solve the problems and answer questions. Therefore, the process of conceptualization and inference of knowledge are fundamental problem solving activities and hence, are essential activities for solving the problem of software ES construction Especially, the access to relevant, up-to-date and reliable knowledge is very important task in the daily work of physicians and nurses. In this study, we propose the conceptualization and inference mechanism for implicit knowledge management in medical diagnosis area. To this purpose, we combined the dynamic knowledge map(KM) and relational database(RDB) into a dynamic knowledge map(DKM). A graphical user-interface of DKM allows the conceptualization of the implicit knowledge of medical experts. After the conceptualization of implicit knowledge, we developed an RDB-based inference mechanism and prototype software ES to access and retrieve the implicit knowledge stored in RDB. Our proposed system allows the fast comfortable access to relevant knowledge fitting to the demands of the current task.

• Structural Engineering and Mechanics
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• v.31 no.3
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• pp.265-276
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• 2009

Various Pushover analysis methodologies have evolved as an easy as well as designers-friendly alternative of nonlinear dynamic analysis for estimation of the inelastic demands of structures under seismic loading for performance based design. In fact, the established nonlinear dynamic analysis to assess the same, demands considerable analytical and computational background and rigor as well as intuitive insight into inelastic behavior for judging suitability of the results and its interpretation and hence may not be used in design office for frequent practice. In this context, the simple and viable alternative of Pushover analysis methodologies can be accepted if its efficacy is thoroughly judged over all possible varieties of the problems. Though this burning issue has invited some research efforts in this direction, still a complete picture evolving very clear guidelines for use of these alternate methodologies require much more detailed studies, providing idea about how the accuracy is influenced due to various combinations of basic parameters regulating inelastic dynamic response of the structures. The limited study presented in the paper aims to achieve this end to the extent possible. The study intends to identify the range of applicability of the technique and compares the efficacy of various alternative Pushover analysis schemes to general class of problems. Thus, the paper may prove useful in judicial use of Pushover analysis methodologies for performance based design with reasonable accuracy and relative ease.