• Journal of the Korea Society of Computer and Information
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• v.14 no.3
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• pp.41-49
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• 2009

Flash memory has become increasingly requestion for the importance and the demand as a storage due to its low power consumption, cheap prices and large capacity medium. This research is to design a high performance flash memory structure for the substitution of a hard-disk by dynamic prefetching of aggressive spatial locality from the spatial smart buffer system. The proposed buffer system in a NAND flash memory consists of three parts, i.e., a fully associative victim buffer for temporal locality, a fully associative spatial buffer for spatial locality, and a dynamic fetching unit. We proposed new dynamic prefetching algorithm for aggressive spatial locality. That is to use the flash memory instead of the hard disk, the proposed flash system can achieve better performance gain by overcoming many drawbacks of the flash memory by the new structure and the new algorithm. According to the simulation results, compared with the smart buffer system, the average miss ratio is reduced about 26% for Mediabench applications. The average memory access times are improved about 35% for Mediabench applications, over 30% for Spec2000 applications.

• Korean small business review
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• v.41 no.3
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• pp.49-75
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• 2019

Market instability offers opportunities as well as the need for careful innovation strategies and learning for a company's survival. Companies that find new opportunities decide to carry out innovation and decide on the size of their investments by considering their position in the market they are aiming for and the intensity of competition. This study was conducted to check whether obstacles to innovation face by SMEs in the manufacturing sector vary depending on the stage of corporate growth and to identify the impact of the government support system on the decision-making process on the performance of innovation. According to the analysis, there were differences in obstacles to innovation depending on the stage of corporate growth. It was found that more innovative SMEs are, more obstacles they face, and to overcome such obstacles, they try to access government support systems more. In addition, the use of a government support system eliminated obstacles to innovation, and the positive and significant effects of investing in innovation were identified. This study is meaningful in that it explicitly approached these hypotheses by applying a multistage model to the process of innovation carried out by SMEs in the manufacturing sector.

• Journal of The Geomorphological Association of Korea
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• v.28 no.3
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• pp.13-26
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• 2021

In mountain gully, channelized debris flow is an important phenomenon in the process of topographical change. Social infrastructure as roads may be damaged by channelized debris flows, but there has been little information about their occurrence and movement to prepare for the risk of the debris flow. Most of the channelized debris flows occur during heavy rains in mountainous valleys that are difficult to access, so there are not many field data. In this study, the topographical characteristics of the catchment, the rainfall and runoff related to the debris flow, the sedimentary pattern and the cross-sectional change of the channel bed, and the underflow velocity of the gravel bed have been investigated and analyzed in the Singi gully where the channelized debris flows occurred. In the catchment, there was almost no sediment runoff because the vegetation combine with the debris landforms and covered the surface. Therefore, the obvious cause of the channelized debris flows is the collapse of the slope and bed of the gully. Even if the gravel, cobbles, and boulders of the channel bed were lost by debris flow, the thalweg change due to debris flow may not be significant because they are supplied from the gully side slope normally. After the gabion structures were installed, the debris flow increased the thalweg change, bed erosion and side slope of the gully. Various sedimentary structures in the gully were classified according to the factors supporting the sedimentation. The hypsometric curve of the gully reflects the debris landforms and vegetation characteristics of the watershed and the sediment runoff due to debris flow, etc. The relationship between the flow velocity and the hydraulic gradient was non-linear under the condition that the porous medium with gully bed gravels is saturated with water. These results may be used as basic data for channelized debris flow research.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.37 no.1
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• pp.88-93
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• 2024

To evaluate the possibility as a multi-level memory medium for the Ge₂Sb₂Te₅/TiN/W-doped Ge₂Sb₂Te₅ cell structure, the crystallization rate and stabilization characteristics according to voltage (V)- and current (I)- pulse sweeping were investigated. In the cell structures prepared by a magnetron sputtering system on a p-type Si (100) substrate, the Ge₂Sb₂Te₅ and W-doped Ge₂Sb₂Te₅ thin films were separated by a barrier metal, TiN, and the individual thicknesses were varied, but the total thickness was fixed at 200 nm. All cell structures exhibited relatively stable multi-level states of high-middle-low resistance (HR-MR-LR), which guarantee the reliability of the multilevel phase-change random access memory (PRAM). The amorphousto-multilevel crystallization rate was evaluated from a graph of resistance (R) vs. pulse duration (T) obtained by the nanoscaled pulse sweeping at a fixed applied voltage (12 V). For all structures, the phase-change rates of HR→MR and MR→LR were estimated to be approximately t<20 ns and t<40 ns, respectively, and the states were relatively stable. We believe that the doublestack structure of an appropriate Ge-Sb-Te film separated by barrier metal (TiN) can be optimized for high-speed and stable multilevel PRAM.

• Korean Journal of Optics and Photonics
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• v.18 no.5
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• pp.351-361
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• 2007

The samples composed of a GST thin film and the protective layers of $ZnS-SiO_2$ or $Al_2O_3$ coated on c-Si substrate were prepared by using the magnetron sputtering method. Samples of three different structures were prepared, that is, i) the GST single film on c-Si substrate, ii) the GST film sandwiched by the protective $ZnS-SiO_2$ layers on c-Si substrate, and iii) the GST film sandwiched by $Al_2O_3$ protective layers on c-Si substrate. The ellipsometric constants in the temperature range from room temperature to $700^{\circ}C$ were obtained by using the in-situ ellipsometer equipped with a conventional heating chamber. The measured ellipsometric constants show strong variations versus temperature. The variation of ellipsometric constants at the temperature region higher than $300^{\circ}C$ shows different behaviors as the ambient medium is changed from in air to in vacuum or the protective layers are changed from $ZnS-SiO_2$ to $Al_2O_3$. Since the long heating time of 1-2 hours is believed to be the origin of the high temperature variation of ellipsometric constants upon the heating environment and the protective layers, a PRAM (Phase-Change Random Access Memory) recorder is introduced to reduce the heating time drastically. By using the PRAM recorder, the GST samples are heated up to $700^{\circ}C$ decomposed preventing its partial evaporation or chemical reactions with adjacent protective layers. The surface image obtained by SEM and the surface micro-roughness verified by AFM also confirmed that samples prepared by the PRAM recorder have smoother surface than the samples prepared by using the conventional heater.

• Journal of Embryo Transfer
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• v.20 no.1
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• pp.55-62
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• 2005

This study was undertaken to access the effect of collection methods on the collection efficiency, blastocyst rate and pregnancy rate after IVP embryo transfer. The ovaries of Hanwoo were obtained from an abattoir and kept on 25 to $28^{\circ}C$ and transported to laboratory within 4 hrs. The oocytes were collected by aspiration of follicles $(2\~6\;mm)$ with or without slicing of ovaries after aspiration. The oocytes were matured in vitro (IVM) for 20 to 24 hrs in TCM-199 supplemented with $10\%$ fetal bovine serum at $39^{\circ}C$ under $5\%\;CO_{2}$ in air. Following routine IVM/IVF procedure, the oocytes and presumed zygotes were cultured for three day in CRlaa medium with BSA. The cumulus cells at 2 to 8-cell stage of embryos removed then the embryos and were cultured in CRlaa medium containing $10\%$ fetal bovine serum in $5\%\;CO_{2}$ at $39^{\circ}C$. The fresh blastocysts cultured for 7 to 9 days were transferred into recipients. The numbers of oocytes recovered form two different methods, the aspiration and slicing after aspiration, were compared to know what. The number of oocytes per ovary was 8.2 and 6.5 in aspiration combining slicing, and aspiration groups, respectively (p<0.05). The cleavage rate in aspiration method are significantly (p<0.05) high than those in slicing post aspiration $(27.9\%)$, and aspiration $(25.5\%)$. The pregnancy .ate in aspiration method $(62.5\%)$ was high than that in slicing method after aspiration $(54.4\%)$. The pregnancy rates of aspiration method and slicing method after aspiration in nullipara $(58.1\%\;vs\;68.2\%)$ was high than that in pluripara $(49.5\%\;vs\;53.2\%)$. The results obtained that the increased number of oocytes per ovary in slicing method after aspiration could be better than that in aspiration method. Pregnancy rate in aspiration method was slightly higher in than that in slicing method after aspiration.

• Korean Journal of Remote Sensing
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• v.34 no.2_1
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• pp.213-225
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• 2018

In order to access the accuracy of the gridded daily Advanced Scatterometer (hereafter DASCAT) ocean surface wind data in the surrounding of Korea, the DASCAT was compared with the wind data from buoys. In addition, the reanalysis data for wind at 10 m provided by European Centre for Medium-Range Weather Forecasts (ECMWF, hereafter ECMWF), National Centers for Environmental Prediction and National Center for Atmospheric Research (NCEP/NCAR, hereafter NCEP), Modern Era Retrospective-analysis for Research and Applications-2 (MERRA-2, hereafter MERRA) were compared and analyzed. As a result, the RMSE of DASCAT for the actual wind speed is about 3 m/s. The zonal components of wind of buoys and the DASCAT have strong correlation more than 0.8 and the meridional components of wind them have lower correlation than that of zonal wind and are the lowest in the Yellow Sea (r=0.7). When the actual wind speed is below 10 m/s, the EMCWF has the highest accuracy, followed by DASCAT, MERRA, and NCEP. However, under the wind speed more than 10 m/s, DASCAT shows the highest accuracy. In the nature of error according to the wind direction, when the zonal wind is strong, all dataset has the error of more than $70^{\circ}$ on the average. On the other hand, the RMSE of wind direction was recorded $50^{\circ}$ under the strong meridional winds. ECMWF shows the highest accuracy in these results. The RMSE of the wind speed according to the wind direction varied depending on the actual wind direction. Especially, MERRA has the highest RMSE under the westerly and southerly wind condition, while the NCEP has the highest RMSE under the easterly and northerly wind condition.

• Asia pacific journal of information systems
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• v.23 no.2
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• pp.1-20
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• 2013

Social commerce has been gaining explosive popularity, with typical examples of the model such as Groupon and Level Up. Both local business owners and consumers can benefit from this new e-commerce model. Local business owners have a chance to access potential customers and promote their products in a way that could not have otherwise been easily possible, and consumers can enjoy discounted offerings. However, questions have been increasingly raised about the value and future of the social commerce model. A recent survey shows that about a third of 324 business owners who ran a daily-deal promotion in Groupon went behind. Furthermore, more than half of the surveyed merchants did not express enthusiasm about running the promotion again. The same goes for the case in Korea, where more than half of the surveyed clients reported no significant change or even decrease in profits compared to before the use of social commerce model. Why do local business owners fail to exploit the benefits from the promotions and advertisements through the social commerce model and to make profits? Without answering this question, the model would fall under suspicion and even its sustainability might be challenged. This study aims to look into problems in the current social commerce transactions and provide implications for the social commerce model, so that the model would get a foothold for next growth. Drawing on justice theory, this study develops theoretical arguments for the effects of transaction characteristics on consumers' distributive justice and purchase intention in the social commerce. Specifically, this study focuses on two characteristics of social commerce transactions-the discount rate and the purchase rate of products-and investigates their effects on consumers' perception of distributive justice for discounted transactions in the social commerce and their perception of distributive justice for regular-priced transactions. This study also examines the relationship between distributive justice and purchase intention. We conducted an online experiment and gathered data from 115 participants to test the hypotheses. Each participant was randomly assigned to one of nine manipulated scenarios of social commerce transactions, which were generated based on the combination of three levels of purchase rate (high, medium, and low) and three levels of discount rate (high, medium, and low). We conducted MANOVA and post-hoc ANOVA to test hypotheses about the relationships between the transaction characteristics (purchase rate and discount rate) and distributive justice for each of the discounted transaction and the regular-priced transaction. We also employed a PLS analysis to test relations between distributive justice and purchase intentions. Analysis results show that a higher discount rate increases distributive justice for the discounted transaction but decreases distributive justice for the regular-priced transaction. This, coupled with the result that distributive justice for each type of transaction has a positive effect on the corresponding purchase intention, implies that a large discount in the social commerce may be helpful for attracting consumers, but harmful to the business after the promotion. However, further examination reveals curvilinear effects of the discount rate on both types of distributive justice. Specifically, we find distributive justice for the discounted transaction increases concavely as the discount rate increases while distributive justice for the regular-priced transaction decreases concavely with the dscount rate. This implies that there exists an appropriate discount rate which could promote the discounted transaction while not hurting future business of regular-priced transactions. Next, the purchase rate is found to be a critical factor that facilitates the regular-priced transaction. It has a convexly positive influence on distributive justice for the transaction. Therefore, an increase of the rate beyond some threshold would lead to a substantial level of distributive justice for the regular-priced transaction, threrby boosting future transactions. This implies that social commerce firms and sellers should employ various non-price stimuli to promote the purchase rate. Finally, we find no significant relationship between the purchase rate and distributive justice for the discounted transaction. Based on the above results, we provide several implications with future research directions.

• Food Science and Preservation
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• v.17 no.3
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• pp.398-404
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• 2010

It is known that onions, or bioactive compounds therein, providehealth benefits. The present study was designed to investigate whether a concentrated onion extract lowered blood lipid levels in rats fed a high-fat diet. Initially, male Sprague-Dawley rats were housed singly in an environment in which temperature and light duration were controlled, and had free access to a nutritionally adequate AIN-93G diet and deionized water. After an acclimatization period, rats were weight-matched and assigned to one of the following five groups: 1) a control group, fed the AIN-93G diet mixed with 10% (w/v) lard and 0.7% (w/v) cholesterol to induce hyperlipidemia (control); 2) three experimental groups, fed the AIN-93G diet mixed with a high-fat source plus concentrated onion extract at three different levels (termed the low-dose, medium-dose, and high-dose groups); and, 3) a placebo group, fed the AIN-93G diet with fats plus the same concentrated extract but devoid of onion-derived material. All five groups freely ingested their respective diets over 6 weeks. At 0, 3, and 6 weeks, blood samples were collected from the orbital sinus following overnight food deprivation. At 6 weeks, livers were collected. Both control and experimental groups continually gained body weight throughout the study. No significant differencein body weight gain was observed among groups. However, the serum concentrations of triglycerides, total cholesterol, and non HDL-cholesterol were significantly reduced by ingestion of concentrated onion extract. Also, the hepatic levels of total lipids and total fatty acids, especially C18:1 (oleic acid), were significantly decreased in rats fed a high level of concentrated onion extract, compared with the control and placebo groups. These results provide clear evidence that ingestion of a concentrated onion extract has a profound inhibitory effect on serum lipid levels in rats fed a high-fat diet. Our findings indicate that a concentrated onion extract may be used to alleviate hyperlipidemia by lowering serum cholesterol and triglyceride levels.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.23
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• pp.155-219
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• 2004

This paper focuses on two recent legislative developments in electronic commerce: the "Uniform Computer Information Transactions Act" ("UCITA") of USA and the "preliminary draft convention on the use of data message in [international trade] [the context of international contracts]" ("preliminary draft Convention") of UNCITRAL. UCITA provides rules contracts for computer information transactions. UCITA supplies modified contract formation rules adapted to permit and to facilitate electronic contracting. UCITA also adjusts commonly recognized warranties as appropriate for computer information transactions; for example, to recognize the international context in connection with protection against infringement and misappropriation, and First Amendment considerations involved with informational content. Furthermore, UCITA adapts traditional rules as to what is acceptable performance to the context of computer information transactions, including providing rules for the protection of the parties concerning the electronic regulation of performance to clarify that the appropriate general rule is one of material breach with respect to cancellation (rather than so-called perfect tender). UCITA also supplies guidance in the case of certain specialized types of contracts, e.g., access contracts and for termination of contracts. While for the most part carrying over the familiar rules of Article 2 concerning breach when appropriate in the context of the tangible medium on which the information is fixed, but also adapting common law rules and rules from Article 2 on waiver, cure, assurance and anticipatory breach to the context of computer information transactions, UCITA provides a remedy structure somewhat modeled on that of Article 2 but adapted in significant respects to the different context of a computer information transaction. For example, UCITA contains very important limitations on the generally recognized common law right of self-help as applicable in the electronic context. The UNCITRAL's preliminary draft Convention applies to the use of data messages in connection with an existing or contemplated contract between parties whose places of business are in different States. Nothing in the Convention affects the application of any rule of law that may require the parties to disclose their identities, places of business or other information, or relieves a party from the legal consequences of making inaccurate or false statements in that regard. Likewise, nothing in the Convention requires a contract or any other communication, declaration, demand, notice or request that the parties are required to make or choose to make in connection with an existing or contemplated contract to be made or evidenced in any particular form. Under the Convention, a communication, declaration, demand, notice or request that the parties are required to make or choose to make in connection with an existing or contemplated contract, including an offer and the acceptance of an offer, is conveyed by means of data messages. Also, the Convention provides for use of automated information systems for contract formation: a contract formed by the interaction of an automated information system and a person, or by the interaction of automated information systems, shall not be denied on the sole ground that no person reviewed each of the individual actions carried out by such systems or the resulting agreement. Further, the Convention provides that, unless otherwise agreed by the parties, a contract concluded by a person that accesses an automated information system of another party has no legal effect and is not enforceable if the person made an error in a data message and (a) the automated information system did not provide the person with an opportunity to prevent or correct the error; (b) the person notifies the other party of the error as soon as practicable when the person making the error learns of it and indicates that he or she made an error in the data message; (c) The person takes reasonable steps, including steps that conform to the other party's instructions, to return the goods or services received, if any, as a result of the error or, if instructed to do so, to destroy such goods or services.