• Animal Bioscience
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• v.34 no.1
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• pp.74-84
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• 2021

Objective: Feed additives that modify rumen fermentation can be used to prevent metabolic disturbances such as acidosis and optimize beef cattle production. The study evaluated the effects of liquid and powdered forms of polyclonal antibody preparation (PAP) against Streptococcus bovis and Fusobacterium necrophorum on rumen fermentation parameters in ruminally cannulated non-lactating dairy cows that were adapted or unadapted to a high concentrate diet. Methods: A double 3×3 Latin square design was used with three PAP treatments (control, powdered, and liquid PAP) and two adaptation protocols (adapted, unadapted; applied to the square). Adapted animals were transitioned for 2 weeks from an all-forage to an 80% concentrate diet, while unadapted animals were switched abruptly. Results: Interactions between sampling time and adaptation were observed; 12 h after feeding, the adapted group had lower ruminal pH and greater total short chain fatty acid concentrations than the unadapted group, while the opposite was observed after 24 h. Acetate:propionate ratio, molar proportion of butyrate and ammonia nitrogen concentration were generally greater in adapted than unadapted cattle up to 36 h after feeding. Adaptation promoted 3.5 times the number of Entodinium protozoa but copy numbers of Streptococcus bovis and Fibrobacter succinogens genes in rumen fluid were not affected. However, neither liquid nor powdered forms of PAP altered rumen acidosis variables in adapted or unadapted animals. Conclusion: Adaptation of cattle to highly fermentable carbohydrate diets promoted a more stable ruminal environment, but PAP was not effective in this study in which no animal experienced acute or sub-acute rumen acidosis.

• Journal of The Korean Association For Science Education
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• v.35 no.4
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• pp.649-663
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• 2015

This study investigated the current state of writing in research papers of science education with focus on the translationese and basic Korean grammar, and found a way of improving the Korean language. The science education research have characteristics of both social science and natural science, and of having more quantitative than qualitative research, which could influence the writing of the research paper. The translationese means the conventional expression originated from foreign language other than Korean. The basic Korean grammar includes 'agreement,' 'spelling, word spacing, punctuation mark,' 'causative suffix,' 'use of English or loanword,' and the translationese is divided in 'English,' 'Japanese,' and 'English and Japanese.' The sentences in nine research papers in the 'Journal of the Korean Association for Science Education' were analyzed, and the problematic sentences were discussed and provided with alternatives. The cases with high frequency include '-jeok,' 'use of English,' 'expression of the plural,' 'passive voice of the verb with -hada,' '-go inneun,' '-eul tonghayeo,' '-e daehayeo,' 'gajida,' 'genitive case marker -eui,' 'passive voice with subject of thing,' and 'causative suffix, -sikida.' Based on the results, the characteristics of writing of science education research papers were described as 'writing of quantitative research,' 'objective writing of academic research,' and 'writing of research of foreign origin.' In order to improve the writing of research paper of science education, the science education researcher should pay attention to basic Korean grammar and the translationese, and be familiar with the concrete examples of problematic cases. The results of this study could be used in the education of writing and grammar of Korean language.

• Structural Engineering and Mechanics
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• v.30 no.6
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• pp.713-732
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• 2008

Serviceability and durability of the concrete members can be seriously affected by the corrosion of steel rebar. Carbonation front and or chloride ingress can destroy the passive film on rebar and may set the corrosion (oxidation process). Depending on the level of oxidation (expansive corrosion products/rust) damage to the cover concrete takes place in the form of expansion, cracking and spalling or delamination. This makes the concrete unable to develop forces through bond and also become unprotected against further degradation from corrosion; and thus marks the end of service life for corrosion-affected structures. This paper presents an analytical model that predicts the weight loss of steel rebar and the corresponding time from onset of corrosion for the known corrosion rate and thus can be used for the determination of time to cover cracking in corrosion affected RC member. This model uses fully the thick-walled cylinder approach. The gradual crack propagation in radial directions (from inside) is considered when the circumferential tensile stresses at the inner surface of intact concrete have reached the tensile strength of concrete. The analysis is done separately with and without considering the stiffness of reinforcing steel and rust combine along with the assumption of zero residual strength of cracked concrete. The model accounts for the time required for corrosion products to fill a porous zone before they start inducing expansive pressure on the concrete surrounding the steel rebar. The capability of the model to produce the experimental trends is demonstrated by comparing the model's predictions with the results of experimental data published in the literature. The effect of considering the corroded reinforcing steel bar stiffness is demonstrated. A sensitivity analysis has also been carried out to show the influence of the various parameters. It has been found that material properties and their inter-relations significantly influence weight loss of rebar. Time to cover cracking from onset of corrosion for the same weight loss is influenced by corrosion rate and state of oxidation of corrosion product formed. Time to cover cracking from onset of corrosion is useful in making certain decisions pertaining to inspection, repair, rehabilitation, replacement and demolition of RC member/structure in corrosive environment.

• Korean Institute of Interior Design Journal
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• v.20 no.6
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• pp.208-217
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• 2011

Recently the importance of the elderly facilities and the eco-friendly buildings is on the rise, due to the rapid increase of the aged population and the more and more serious global environment issues, respectively. Thus, the purpose of this study is to suggest an eco-environmental improvement plan which aims to improve the quality of life for the aged in planning nursing homes hereafter by reviewing the theory of the eco-friendly architectural concept and the same conceptual design, which become the issues of late, and thus analyzing the state of applying the eco-friendly design techniques to the municipal nursing homes located in Seoul. In this study its direction of the eco-friendly design required in nursing homes was established by reviewing the characteristics which the aged and nursing homes may have, and thus extracting the elements required for the quality of life for them. The theoretical studies showed that the environment-friendly natural elements necessary for the nursing houses are light, air and plants, from which three design elements are obtained: daylighting, natural ventilation and natural landscape. In conclusion, the eco-friendly nursing homes must be planned to improve the quality of life for the aged by recognizing that the eco-friendly architecture concept, emerged as a new paradigm, is the one to be put before all the considerations for those who are sensitive to the environment, and thus reviewing the characteristics found out from them.

• Korean Journal of Social Welfare
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• v.61 no.3
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• pp.5-28
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• 2009

The purpose of this study is to examine the legal attribute of subsidiarity principle on the National Basic Livelihood Security Act. The principle of subsidiarity is applied to the regulation for 'fundamental principle of benefits' on the National Basic Livelihood Security Act, therefore it functions as legal theory. However, due to its both positive and negative characteristics it becomes to be interpreted and applied in a different meaning depending on the normative characteristics of related laws. In brief, as the passive meaning of subsidiarity principle guarantees the freedom of civilian by limiting national power, it is reasonable in social control norm like criminal law. However, as nation's active role of intervention and support is required in order to protect basic standard of human life according to the principle of Social(welfare)State, the active meaning of subsidiarity principle is reasonable in Social Security law, especially in public assistance. Hence, the principle of subsidiarity on the National Basic Livelihood Security Act becomes to realize, justice, goal fitness and legal stability when it is operated by system with interpreting in an active meaning.

• Corrosion Science and Technology
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• v.17 no.2
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• pp.68-73
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• 2018

Substitution of hip and knee joints by CoCr alloys is in great demand due to their high wear resistance and good biocompatibility. Understanding of tribocorrosion in joint replacements requires study of variables such as coefficient of friction and the choice of a proper corrosive medium in wear-corrosion tests carried out in the lab. The objective of this study was to characterize tribocorrosion behaviour of CoCr alloy with low (LCCoCr) and high carbon (HCCoCr) contents in several corrosive media: NaCl, Phosphate Buffer Solution (PBS), and PBS with hyaluronic acid (PBS-HA). Tribocorrosion tests were carried out on a pin-on-disk tribometer with an integrated electrochemical cell. A normal load of 5N was applied on the alumina ball counterpart at a rotation rate of 120 rpm. Coefficient of friction (COF) was measured and tribocorrosion behaviour was characterized by in situ application of electrochemical techniques. HCCoCr alloy immersed in PBS-HA showed the best tribocorrosion behaviour with the lowest COF. In this case, in situ measurement of corrosion potential and the impedance data under wear corrosion process showed an active state while passive film was continuously destroyed without possibility of regeneration.

• 한국전산유체공학회:학술대회논문집
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• 2009.04a
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• pp.19-19
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• 2009

Dynamic Stall is a flow phenomenon which occurs on the retreating side of helicopter rotor blades during forward flight. It also occurs on blades of stall regulated wind turbines under yawing conditions as well as during gust loads. Time scales occurring during this process are comparable on both helicopter and wind turbine blades. Dynamic Stall limits the speed of the helicopter and its manoeuvrability and limits the amount of power production of wind turbines. Extensive numerical as well as experimental investigations have been carried out recently to get detailed insight into the very complex flow structures of the Dynamic Stall process. Numerical codes have to be based on the full equations, i.e. the Navier-Stokes equations to cover the scope of the problems involved: Time dependent flow, unsteady flow separation, vortex development and shedding, compressibility effects, turbulence, transition and 3D-effects, etc. have to be taken into account. In addition to the numerical treatment of the Dynamic Stall problem suitable wind tunnel experiments are inevitable. Comparisons of experimental data with calculated results show us the state of the art and validity of the CFD-codes and the necessity to further improve calculation procedures. In the present paper the phenomenon of Dynamic Stall will be discussed first. This discussion is followed by comparisons of some recently obtained experimental and numerical results for an oscillating helicopter airfoil under Dynamic Stall conditions. From the knowledge base of the Dynamic Stall Problems, the next step can be envisaged: to control Dynamic Stall. The present discussion will address two different Dynamic Stall control methodologies: the Nose-Droop concept and the application of Leading Edge Vortex Generators (LEVoG's) as examples of active and passive control devices. It will be shown that experimental results are available but CFD-data are only of limited comparison. A lot of future work has to be done in CFD-code development to fill this gap. Here mainly 3D-effects as well as improvements of both turbulence and transition modelling are of major concern.

• Archives of design research
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• v.18 no.4 s.62
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• pp.225-236
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• 2005

As a fresh trial using humorous items to escape from economic recession and uncertain state of mind regarding politics and society, fun is emerging as a keyword in design area. This study classified various use of fun reflected in modern fashion design according to the theme, and analyzed the mod of expression to identify formative characteristics. Through these processes, this study built conceptual structure of fun in fashion design. 412 fashion designs which represent fun were collected from 2001 $S/S{\sim}2005$ F/W collections. Data were analyzed and categorized. Results showed that the theme of fun in the modern fashion design could be classified into humor, kidult, irony, satire/parody, storytelling, and play. The design elements mainly used were color silhouette, letter, object, and drawing, while the design principles were distortion/exaggeration, incongruity, and repetition. In addition, these expressions were related to the traditional humor theory: incongruity-resolution, superior, and relief theories. The fun in modern fashion design has such value as affirmation, warmness, entertainment, youth, contradiction, surprise, deviate, allusion, attack, and description, Finally, in regard to the subject, the fun provides active experience like play as well as passive acceptance.

• Journal of Oral Medicine and Pain
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• v.14 no.1
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• pp.57-66
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• 1989

66 patients with temporomandibular disorders were selected for experimental group, and 45 normal subjects who were Dental students were selected for control group. Average age of experimental group was 30.5 years, Male to Female ratio was 2 : 3, and their age distribution were teen-ages to seventh decades. Transcranial radiography (TR) with Denar Accurad 100 was used for each group to get the values of width in joint spaces and to investigate the bony changes of articular surfaces and relative condylar position to articular fossa. In addition to TR, clinical interview and routine charting about amount of mandibular movements and occlusal variations were carried out in experimental group. The obtained results were as follows : 1. The mean values of joint space with in control group were 2.15mm to anterior, 2.98mm to superior and 2.29mm to posterior and the value of relative condylar position to the deepest portion of articular fossa was 0.21mm to anterior. In experimental group, those values were 2.01mm, 2.14mm 2.22mm and 0.12mm to posterior in sequence, respectively. Joint spaces in experimental group, therefore, were inclined to decreased, and relative condylar position was inclined to retrude. Joint space in control group showed symmetric condylar position, but in experimental group showed asymmetry. 2. Non-affected joints with no bony changes in experimental group showed the narrowest joint spaces which were thought to manifest the abnormal stress to non-affected side to dysfunctional state of contralateral affected joints. 3. Amount of mandibular movements in experimental group were within normal values in lateral movements and in protrusive movement but in opening movement with or without passive stretch, those were lower than normal values. Frequency of occlusal variation, for example, protrusive posterior contacts, open bite, median line shift to lateral side were inclined to increase with bony changes and with crepitus.

• Journal of Institute of Control, Robotics and Systems
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• v.6 no.8
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• pp.638-651
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• 2000

When the bandwidth resources in a packet-switched network are shared among sessions by MAX-MIN flow control each session is required to transmit its data into the network subject to the MAX-MIN fair rate which is solely determined by network loadings. This passive behavior of sessions if fact can cause seri-ous QoS(Quality of Service) degradation particularly for real-time multimedia sessions such as video since the rate allocated by the network can mismatch with what is demanded by each session for its QoS. In order to alleviate this problem we extend the concept of MAX-MIN fair bandwidth allocations as follows: Individual bandwidth demands are guaranteed if the network can accommodate them and only the residual network band-width is shared in the MAX-MIN fair sense. On the other hand if sum of the individual bandwidth demands exceeds the network capacity the shortage of the bandwidth is shared by all the sessions by reducing each bandwidth guarantee by the MAX-MIN fair division of the shortage. we present a novel flow control algorithm to achieve this extended MAX-MIN fairness and show that this algorithm can be implemented by the existing ATM ABR service protocol with minor changes. We not only analyze the steady state asymptotic stability and convergence rate of the algorithm by appealing to control theories but also verify its practical performance through simulations in a variety of network scenarios.