• Journal of the Korean Applied Science and Technology
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• v.19 no.4
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• pp.339-348
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• 2002

Self-diffusion coefficients of colloidal ass9Ciation structures in the aqueous solutions of anionic ammonium dodecyl sulfate (ADS) and cationic octadecyltrimethylammonium chloride (OTAC) surfactants were measured by pulsed-gradient spin echo NMR. The results were interpreted on the basis of the ADS/OTAC/water phase diagram. Crossing the phase boundaries, significant changes in self diffusion coefficients were observed and well correlated to the phase diagram. For the micelles their apparent radii were obtained from Stokes-Einstein equation. Their values were 15 for the ADS micelles and 54 ${{\AA}}$ for the OTAC micelles, respectively. For vesicles which were formed spontaneously at different relative amounts of the surfactants and total surfactant concentrations, the radius was measured as 50 to 200 nm. This result is in fair agreement with those by TEM and light scattering.

• Journal of Communications and Networks
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• v.8 no.4
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• pp.391-400
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• 2006

With the on-going wireless access technologies, the Internet has become accessible anytime anywhere. In wireless networks, link errors significantly degrade the performance of the transmission control protocol (TCP). To cope with this issue, this paper improves the recently-proposed terrestrial REFWA (T-REFWA) scheme by adding a new error recovery mechanism to its original design. In the T-REFWA scheme, senders are acknowledged with appropriate sending rates at which an efficient and fair utilization of network resources can be achieved. As the feedback values are computed independently of link errors, senders can keep transmitting data at high rates even in case of link error occurrences. Using this feature, the proposed error recovery mechanism can achieve high throughput in environments with high bit error rates. The throughput is further improved by disabling the exponential back-off algorithm of TCP so that long idle times are avoided in case of link errors. We show through simulations that the proposed method improves TCP performance in high bit error rates. Compared with several TCP variants, the proposed error recovery scheme exhibits higher link utilization and guarantees system fairness for different bit error rates.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.18 no.6
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• pp.663-673
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• 2008

The purpose of this study is to analyze the appropriate evaluation method for the water supply and drain noise of bathroom in apartment and to propose some fundamental idea on its regulation. For this reason, it was studied the acoustical characteristics of water supply and drain noise as modifying the water supply pressure for the washbasins and toilet stools and suggested the optimum evaluation method through psychoacoustic test. As a result of investigation of the levels by evaluating the adjectives and noise sources with 7-step criteria corresponding to each level of plumbing noises and analysis of the correlation between physical evaluation values by comparing the criteria, dB(A), N, and NC, with subject's response, determination coefficient($R^2$) was shown to be relatively fair or higher ranged from 0.65 to 0.92. It is shown that 'Harsh', 'Nervous', 'Unpleasant', 'Distasteful', and 'Repellent' as a second factor are to be appropriate to evaluate plumbing noise. Above these results could be used in basic data establishing KS(Korean Standard) for evaluation and rating procedure and measures reducing these noise.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.3
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• pp.418-423
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• 2007

Meats with alginate binders including sodium alginate, glucono-delta-lactone and calcium carbonate were tested in restructured steaks made from M. pectoralis profundus of beef steers in terms of meat quality and binding ability by tumbling time. The treatment with 25 min tumbling time was significantly lower (p<0.05) for crude protein than 5 and 15 min, while higher (p<0.05) for moisture content. This corresponded with sensory panel juiciness ratings, which showed the treatment for longer tumbling times to be significantly juicier (p<0.05) than that for a shorter time. Cooking loss decreased (p<0.05) linearly with an increased tumbling time, and Kramer shear force also significant decreased (p<0.05) with tumbling time. This corresponded with sensory panel tenderness ratings, which showed that the treatment for longer tumbling times was more tender (p<0.05). The texture results indicated that longer tumbling time had lower (p<0.05) hardness and chewiness values. Sensory panels ranked binding ability in the order 5 min, 15 min and 25 min from best to worst, and the overall acceptability for slices from roasts of treatments for 5 and 15 min were rated by the sensory panelists as moderate to very acceptable, but those for 25 min were rated as fair to moderate.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.5
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• pp.31-40
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• 2020

This study investigates whether other comprehensive income (OCI) reported in the statement of comprehensive income (one of the main financial statements after the adoption of K-IFRS) predicts a firm's future performance. Using the quarterly data of Korean listed companies, we examine the association between OCI estimates and future earnings. First of all, we find that OCI is positively associated with earnings in both 1- and 2-quarter ahead, supporting the predictive value of OCI. When we break down OCI into its individual components, our results suggest that the net unrealized gains/losses on available-for-sale (AFS) investment securities are positively associated with future earnings, while the other components (e.g., net unrealized gains/losses on valuation of cash flow hedge derivatives) present insignificant results. In addition, we investigate whether the reliability in OCI estimates enhances the predictive value of OCI to predict future performance. We find that the predictive ability of OCI, in particular the net unrealized gains/losses on available-for-sale (AFS) investment securities, becomes more pronounced when firms are audited by the Big 4 audit firms. Overall, our study suggests that information content embedded in OCI can provide decision-useful information that is helpful for the prediction of future firm performance.

• Korean Journal of Organic Agriculture
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• v.28 no.1
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• pp.1-30
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• 2020

This study argues that expanding the multifunctionality of agriculture (MFA) may mitigate existing agricultural problems. To do that this study redefines the concept and scope of the MFA and presents practical tasks to achieve it. Theorizing the MFA begins with the theory of sustainability and first identifies the link between sustainability and MFA. Later, considering the limitations of the existing sustainability theories, we examined where the false linkages leading to the destruction of environmental and social relations originated, and employed the (Re)productivity [(Re)produktivitat] theory in order to obtain alternatives. Research shows that welfare effects of the MFA on humans and the environment are not less than those derived from the agricultural products supplied to the real market, but the values are not recognized. The absence of proper care and compensation is the basis of agricultural problems in Korea. Therefore, this study acknowledges that the MFA is as much worthy as real agricultural production, and insists that appropriate compensation and care should be given to humans (farmers) and nature (agricultural ecosystem) in order to maintain and expand the MFA. In other words, a virtuous cycle between sustainability and the MFA means that the process spreads sustainable farming methods to expand the MFA, forms social consensus on it, and pays fair remuneration for agriculture from the public sector. Transition to such a virtuous cycle requires re-establishing the definition and scope of the MFA, implementing targeting policy, motivating policy targets, strengthening human capacity, and arranging maturity time.

• Journal of Communications and Networks
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• v.5 no.3
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• pp.249-257
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• 2003

Ring networks are very commonly exploited among local area and metropolitan area networks (LAN/MAN), whereas cells or small fixed-size packets are widely used in synchronized ring networks. In this paper, we present an analytical method for evaluating the delay-throughput performance of a MAC protocol with multiple self-tokens in a slotted ring network under uniform traffic. In our analysis, we introduce the stationary probability, which indicates the number of packets in a node. Also, it is assumed that each node has a sufficiently large amount of self-tokens, and a slotted ring has the symmetry. The analytical results with respect to delay-throughput performance have similar values to computer simulated ones. Furthermore, in order to achieve fair access under non-uniform traffic, we propose an adaptive MAC protocol, where the number of self-tokens in a node dynamically varies, based on the number of packets transmitted within a specified period. In the proposed protocol, when the number of packets transmitted by a node within a specified period is larger than a specified threshold, the node decreases the number of self-tokens in a per-node distributed method. That results in creating free slots in the ring, thus all nodes can obtain an equal opportunity to transmit into the ring. Performance results obtained by computer simulation show that our proposed protocol can maintain throughput fairness under non-uniform traffic.

• Journal of the Korean Society of Tobacco Science
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• v.20 no.2
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• pp.139-143
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• 1998

The occurrence and physico-chemical properties of flat leaves found in 1997 curing trial related to the prevention of occurrence of flat leaves at bulk curing of flue-cured tobacco were investigated and compared with those of normal leaves. Cured leaves of NC82 were separated into 4 classes of none, slight, fair and severe symptoms of flat leaf by the percentage of flattened parts to whole leaf area. The flat leaves were mostly found among the leaves of lower stalk position, and it was estimated that growth rate of lower leaves also influenced on the occurrence of flat leaves. In chromatic aberration of cured leaf, flat leaves showed remarkably lower b and L values than in those of normals but there was no difference in a value. On the other hand, in chemical analyses of flat leaf samples, nicotine, total sugar, ether extract and total nitrogen contents were decreased with the degree of flat symptoms. In physical properties, filling capacity of cured leaves was decreased with the degree of flat symptoms comparing with those of normal leaves, while shatter index was showed a reverse tendency, and then within the same leaf, flat parts were decreased in total sugar, ether extract and filling capacity compared with those of normal ones, but remarkably increased in shatter index, and there was no difference in nicotine and total nitrogen contents.

• Korean Journal of Veterinary Research
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• v.16 no.2
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• pp.179-185
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• 1976

The gross appearance, cellular constituents, and quality of mucin clot of synovial fluid from the normal tibiotarsal joints of 57 healthy Korean cattle were investigated. The results obtained were summarized as followings. 1. The gross appearance of the synovial fluid were quite clear without any minute particles of flocculent, colourless (78.95%) or slightly yellowish (21.05%), and it did not coagulate within the 24 hours after sampling. 2. The mean number of leucocytes for the entire group was $127.68{\pm}13.84/mm^3$ (SE) with a range of 0 to $627/mm^3$ for individual samples. In the total cell count no significance among the investigated age and sex categories was found. 3. The mean differential values for the groups ware: neutrophil, $9.36{\pm}1.67%$; lymphocyte, $57.66{\pm}8.34%$; monocyte, $24.70{\pm}2.22%$; eosinophil, $1.45{\pm}0.27%$; and macrophage, $5.83{\pm}1.13%$. No basophils were observed in stained smears of synovial fluid. 4. Normal mucin clot quality was recorded for 94.7% of the animals, but 5.3% were observed to have fair mucin clot quality. Quality of mucin clot was approximately equal for bulls, cows, and calves.

• Journal of Arbitration Studies
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• v.23 no.2
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• pp.165-190
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• 2013

As intellectual property rights are perceived as the key element of creating added values and securing competitiveness, the result of intellectual property rights disputes play an important role in the success of companies. As seen from above strong points of an Alternative Dispute Resolution (ADR) system in Chapter III, intellectual property rights disputes increasingly tend to be resolved by ADR rather than litigation. Discussions about and operation of ADR are already being actively carried out in many countries, and major ADR institutions have been acquiring experience in a variety of intellectual property rights disputes. To enhance the use and recognition of ADR as the way of resolving the Intellectual Property Rights disputes in Korea, this study suggested the following three ways. First, domestic ADR institutions, the Korean Commercial Arbitration Board (KCAB) will need to establish cooperative systems with prominent overseas institutions to lead the disputing parties to fair resolutions as well as to instill trust in international arbitration institutions. Second, they will need to contribute to the promotion of arbitration systems throughout society by developing and applying a variety of arbitration systems as well as securing a pool of professionals. Finally, the arbitration rules will need to be continuously improved to deal with disputes promptly and reinforce privacy protection.