• Asian-Australasian Journal of Animal Sciences
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• v.22 no.9
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• pp.1279-1287
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• 2009

Concentrated livestock production has led to soil nutrient accumulation concerns. To reduce the environmental impact, it is necessary to understand current recommended livestock feeding practices. Two experiments were conducted to compare the effects of trace mineral supplementation on performance, carcass composition, and fecal mineral excretion of phase-fed, grow-finish pigs. Crossbred pigs (Experiment 1 (Exp. 1), (n = 528); Experiment 2 (Exp. 2), (n = 560)) were housed in totally-slatted, confinement barns, blocked by weight, penned by sex, and randomly assigned to pens at approximately 18 kg BW. Treatments were allocated in a randomized complete block design (12 replicate pens per treatment) with 9 to 12 pigs per pen throughout the grow-finish period. In Exp. 1, the control diet (Io100) contained Cu as $CuSO_{4}$, Fe as $FeSO_{4}$, and Zn (of which 25% was ZnO and 75% was $ZnO_{4}$) at concentrations of 63 and 378 mg/kg, respectively. Treatment 2 (O100) contained supplemental Cu, Fe, and Zn from organic sources (Bioplex, Alltech Inc., Nicholasville, KY) at concentrations of 19, 131, and 91 mg/kg, respectively, which are the commercially recommended dietary inclusion levels for these organic trace minerals. Organic Cu, Fe, and Zn concentrations from O100 were reduced by 25% and 50% to form treatments 3 (O75) and 4 (O50-1), respectively. In Exp. 2, treatment 5 (Io25) contained 25% of the Cu, Fe, and Zn (inorganic sources) concentrations found in Io100. Treatment 6 (O50-2) was identical to the O50-1 diet from Exp. 1. Treatment 7 (O25) contained the experimental microminerals reduced by 75% from concentrations found in O100. Treatment 8 (O0) contained no trace mineral supplementation and served as a negative control for Exp. 2. In Exp. 1, tenth-rib backfat, loin muscle area and ADG did not differ (p>0.05) between treatments. Pigs fed the control diet (Io100) consumed less feed (p<0.01) compared to pigs fed diets containing organic trace minerals, thus, G:F was greater (p = 0.03). In Exp. 2, there were no differences among treatment means for loin muscle area, but pigs fed the reduced organic trace mineral diets consumed less (p<0.05) feed and tended (p = 0.10) to have less tenth-rib backfat compared to pigs fed the reduced inorganic trace mineral diet. Considering that performance and feed intake of pigs was not affected by lower dietary trace mineral inclusion, mineral excretion could be reduced during the grow-finish phase by reducing dietary trace mineral concentration.

• The korean journal of orthodontics
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• v.21 no.2 s.34
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• pp.259-272
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• 1991

Orthodontic traction has been suggested as the treatment of choice for intrusive luxation injuries. Prior research has shown orthodontic forces to be ineffective in the presence of ankylosis or in cases with zero mobility following the injury. If orthodontic traction is to be effective, it must be initiated prior to the onset of ankylosis. The purpose of this study was to describe the effects of intrusive luxation at various times following the injury, and to determine the time of the onset of ankylosis, and to examine what effect immediate partial luxation has on the onset of ankylosis. Eight young mongrel dogs were utilized for this study. Intrusive luxation was produced with an axial impact using a gravity hammer and a specially designed holding device on 4 teeth (2 max. and 2 man. first premolars) in each dog. The teeth were intruded approximately 3-4mm in an axial direction. One maxillary and one mandibular premolars were partially luxated with the other two teeth being untouched. Pre and posttrauma tooth position was documented with plaster models and radiographs taken with an individualized X-ray jig. Dogs were sacrificed immediately following the injury and at 1, 2, 4, 7, 10, 14 and 21 days respectively. Tetracycline was administered as a vital bone marker 24 hours before sacrifice. Block sections of the tooth and alveolus were prepared for decalcified and non decalcified histologic sections. The effects of traumatic intrusion were analyzed by means of model casts, radiographs, tetracycline bone marking and histologic preparations. The results obtained were as follows: 1. The animal sacrificed immediately following the injury displayed alveolar fractures, torn periodontal ligaments, and areas of direct tooth-bone contact. 2. The odontoblastic layer of the pulp was disorganized as early as 24 hours after the injury. 3. Bony remodeling was noted at 4 days along with active surface resorption. 4. Ankylosis was first seen 7 days after the injury. 5. Osteogenesis in the dentin (thick tetracycline bands) was observed 7 days after the injury. 6. There was no progressive root resorption and ankylosis where the periodontal ligament has been healed. 7. The Luxated group showed significantly more root resolution and ankylosis than the Nonluxated group with increased observation periods. The results suggest that ankylosis may occur within the first week following the injury, and hence orthodontic traction should be initiated as soon after the injury as possible.

• The Journal of the Korea Contents Association
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• v.13 no.12
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• pp.595-603
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• 2013

Touchscreen is now installed in the majority of information devices thanks to the developed digital technology. In case of copiers, although touchscreen was installed earlier than any other information device, current user interface indicates that conventional methods have been maintained without any special re-validation. But, since common office devices such as copiers have brief usage time and clear, straightforward purposes, user experience between an user and device is perhaps an important element. Nevertheless, conservativeness of the market and the fact that users and buyers are not always the same are a stumbling block to actively changing UI. Recently, however, as hardware element, buttons, have moved to touchscreen mostly for smartphone, and common and public devices have seen rapid changes in UX, mostly with touchscreen, it has led to high demand for changes in UX of copiers. To remedy the issues with copiers, a literature review was conducted through existing studies and user evaluation based on user survey and prototype was done to examine the copier's UI elements and relevant changes in usage. In particular, a new direction for UX of copiers was suggested by analyzing the impact of differences between software button-oriented UI and hardware button-oriented UI on users and usability. This study findings could be used as basic data for improving the usability of future common devices including copier and UX design.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.5
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• pp.54-63
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• 2018

In this study, the stability and economic feasibility of a MSE (Mechanically stability earth) wall with a pre-cast concrete pacing panel was investigated for a standard section of highway. Based on the design criteria, the MSE walls of the panel type were designed considering the load conditions of the highway, such as the dead load of the concrete pavement, traffic load, and impact load of the barrier. The length of the ribbed metal strip was arranged at 0.9H according to the height of the MSE walls. Because the length of the reinforcement was set to 0.9H according to the height of the MSE wall, the external stability governed by the shape of the reinforced soil was not affected by the height increase. The factor of safety (FOS) for the bearing capacity was decreased drastically due to the increase in self-weight according to the height of the MSE wall. As a result of examining the internal stability according to the cohesive gravity method, the FOS of pullout was increased and the FOS of fracture was decreased. As the height of the MSEW wall increases, the horizontal earth pressure acting as an active force and the vertical earth pressure acting as a resistance force are increased together, so that the FOS of the pullout is increased. Because the long-term allowable tensile force of the ribbed metal strip is constant, the FOS of the fracture is decreased by only an increase in the horizontal earth pressure according to the height. The panel type MSE wall was more economical than the block type at all heights. Compared to the concrete retaining wall, it has excellent economic efficiency at a height of 5.0 m or more.

• The Korean Journal of Financial Management
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• v.26 no.1
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• pp.65-94
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• 2009

The event of change in KOSPI 200 Index composition is one of the main subjects for the test of EMH. According to EMH, when a certain event is not related with firm's fundamental value, stock price should not change after the announcement of news. This hypothesis leads us to the conclusion of horizontal demand curve of stock. This logic was questioned by Shleifer(1986) and argued that downward sloping demand curve hypothesis was supported. But Harris and Gruel(1986) found a different empirical evidence that price reversal occurs in the long run, which is called price pressure hypothesis. They argued that short term price effect by large block trading (price pressure) is offset in the long run because these event is unrelated to fundamental value. Therefor, they argued that EMH can not be rejected in the long run. Until now, there are two empirical studies with Korean market data in this area. Using a data with same time period of $1996{\sim}1999$, Kweon and Park(2000) and Ahn and Park(2005) showed that stock price or beta is not significantly affected by change in index composition. This study retested this event expanding sample period from 1996 to 2006, and analyzed why this event was considered an uninformative events in the preceding studies. We analyzed a market impact by separating samples according to firm size and market condition. In case of newly enlisted firm, we found the evidence supporting price pressure hypothesis on average. However, we found the long run price effect in the sample of large firms under bearish markets. At the same time, we know that the number of samples under the category of large firms under bearish markets is relatively small, which drives the same result of supporting the hypothesis that change in index composition is a non-informative event on average. Also, the long run price effect of large size firms under bearish markets was supported by the analyses using trading volumes. On the other hand, in case of delisting from the index, we found the long run price effect but that was not supported by trading volume analyses.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.37 no.4
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• pp.729-738
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• 2017

With the signing of the Paris Agreement, which is the new climate change agreement at the end of 2015, it will have a great impact on Korea environmental policy. The construction industry, which accounts for 42% of Korea's total $CO_2$ emissions, has been implementing various policies to improve the environmental problems. However, it is only applying passively to other projects except eco-friendly building certification. This is because most of the eco-related systems are based on building facilities. Therefore, there is a need for a new eco - friendly design evaluation model that can be widely applied not only to architecture but also to civil engineering facilities. In this study, a new model is developed based on the existing VE model, which adds new factors to evaluate the environmental friendliness, potential environmental pollution concept and environmental risk of facilities. This model is an eco-friendly design evaluation model that enables decision makers to effectively select alternative environmental criteria at the design stage. As a result of the case analysis of the block retaining wall and the alternative retaining wall, the value of the eco - friendly value of the alternative was 1.026 times higher than the original one. If this model is used at the design stage, it is expected to contribute not only to the construction of environmentally friendly facilities but also to the reduction of carbon emissions.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.48 no.5
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• pp.16-24
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• 2011

The IEEE 802.11 wireless LAN (Local Area Network) is widely used for wireless access due to its easy deployment and low cost. Multicast in wireless LANs is very useful for transmitting data to multiple receivers compared to unicast to each receiver. In the IEEE 802.11 wireless LAN, multicast transmissions are unreliable since multicast data packets are transmitted without any feedback from receivers. Recently, various protocols have been proposed to enhance the reliability of multicast transmissions. They still have serious problems in reliability and efficiency due to the excessive control overhead by the use of a large number of control packets in the error recovery process, and due to a large number of retransmissions to satisfy all receivers. In this paper, we propose an effective scheme called PTRM(Proactive Transmission based Reliable Multicast). The proposed scheme uses a block erasure code to generate parity packets and to reduce the impact of independent packet error among receivers. After generating parity packets, the PTRM transmits data packets as many as receivers need to recover error, and then requests feedback from them. The simulation results show that the proposed scheme provides reliable multicast while minimizing the feedback overhead.

• Polymer(Korea)
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• v.33 no.6
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• pp.608-614
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• 2009

The cation-exchange membrane which was sulfonated styrene-ethylene/buthlene-styrene(SEBS) block copolymer containing the high impact polystyrene (HIPS) was prepared via post-sulfonation and casting method using the epoxidized polybutadiene and divinylbenzene as crosslinking agents. Post-sulfonation was carried out with sulfuric acid as sulfonating agent and silver sulfate as initiator in the nitrogen atmosphere. The basic properties of membranes, degree of sulfonation (DS), water uptake, ion-exchange capacity (IEC), electrical resistance, and modulus have been examined. DS of membrane increased with increasing the sulfonation time. The maximum DS of membrane containing 10 wt% HIPS was 83.6 %. The water uptake and IEC of membranes gradually increased as increasing the DS. The maximum water uptake and IEC of membranes were 43.8 % and 1.14 meq/g, respectively. The lowest electrical resistance of membrane containing the 20 wt% HIPS was $83\;\Omega{\cdot}cm^2$. The electrical conductivity of membrane containing 10 wt% HIPS was $1.22\times10^{-4}S/cm$. The modulus of membrane increased with increasing DS and these values were 153 and $204\;kgf/cm^2$ before and after sulfonation, respectively.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.48 no.1
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• pp.81-88
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• 2020

Flight data recorder is a equipment that records data required for investigation of aircraft accidents and should be developed in compliance with the ED-112A standard. Unlike general data storage device, flight data recorder must be able to recover data after an aircraft accident, requiring a housing and a memory board to protect data in extreme environments. To attain this performance, we designed a housing that can withstand the test by analyzing the physical environment of the impact, shear/tensile, penetration resistance and static crush test of the crash survival test and minimized the size and weight compared to the existing one in consideration of the installation of the aircraft in this paper. Insulation material and thermal block material were applied to endure high and low temperature fire so that the internal temperature does not rise above 150℃ even in 260℃, 10 hour environment. In addition, the memory board is designed to minimize the size and we devise a hoping programming method to prevent continuous data loss of more than 16 seconds. Through this, Crash protected memory module that satisfies ED-112A was completed.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.12
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• pp.1923-1932
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• 2019

Objective: We investigated visual marbling level (VML) influence on pork loin physicochemical traits, consumer palatability responses, VML liking, purchase intent, and their relationships. Methods: For each of five slaughtering dates, at 24-h postmortem, nine paired Duroc castrated male boneless Longissimus dorsi (LD) muscles were categorized into low (LM, score 1 to 2, n = 3), medium (MM, score 3 to 4, n = 3), and high (HM, score 5 to 6, n = 3) VML. Meat physicochemical quality traits and consumer responses (n = 389) on palatability and VML liking, and purchase intent were evaluated. The experiment was in randomized complete block design. Analysis of variance, Duncan's multiple mean comparisons, and correlation coefficients were determined. Results: VML correspond to crude fat (r = 0.91, p<0.01), but both were reversely related to moisture content (r = -0.75 and -0.91, p<0.01, respectively). As VML increased, ash (p<0.05) and protein (p = 0.072) decreased, pH and $b^{\star}$ increased (p<0.05), but drip, cooking (p<0.05) and thawing (p = 0.088) losses decreased. Among treatments, muscle fiber diameter, sarcomere length, total and insoluble collagen contents, $L^{\star}$, and $a^{\star}$ did not differ (p>0.05). Compared to the others, HM had lower collagen solubility percentage (p<0.05), but similar (p>0.05) Warner-Bratzler shear force (WBSF). No differences (p>0.05) were found in juiciness, overall flavor, oiliness, and overall acceptability, but HM was more tender (p<0.05) than the others. Based on VML, consumers preferred MM to HM (p<0.05), while LM was similar to MM and HM (p>0.05). Corresponding to VML preference (r = 0.45, p<0.01), consumers (83%) would (p<0.01) definitely and probably buy MM, over LM (74%), and HM (68%), respectively. Conclusion: Increasing VML in pork LD altered its chemical composition, slightly increased pH, and improved water holding capacity, thereby improving its tenderness acceptability. Marbling might reduce chewing resistance, as lower collagen solubility in HM did not impact tenderness acceptability and WBSF. While HM was rated as most tender, consumers visually preferred and would purchase MM.