• Journal of Distribution Science
• /
• v.14 no.11
• /
• pp.83-90
• /
• 2016

Purpose - During the last two years, convenient stores (CS) are emerging as one of the most fast-growing retail trades in Korea. The goal of this work is to forecast and to analyze sales at CS using ARIMA-Intervention model (IM) and exponential smoothing method (ESM), together with sales at supermarkets in South Korea. Considering that two retail trades above are homogeneous and comparable in size and purchasing items on off-line distribution channel, individual behavior and characteristic can be detected and also relative superiority of future growth can be forecasted. In particular, the rapid growth of sales at CS is regarded as an everlasting external event, or step intervention, so that IM with season variation can be examined. At the same time, Winters ESM can be investigated as an alternative to seasonal ARIMA-IM, on the assumption that the underlying series shows exponentially decreasing weights over time. In case of sales at supermarkets, the marked intervention could not be found over the underlying periods, so that only Winters ESM is considered. Research Design, Data, and Methodology - The dataset of this research is obtained from Korean Statistical Information Service (1/2010~7/2016) and Survey of Service Trend of Korea Statistics Administration. This work is exploited time series analyses such as IM, ESM and model-fitting statistics by using TSPLOT, TSMODEL, EXSMOOTH, ARIMA and MODELFIT procedures in SPSS 23.0. Results - By applying seasonal ARIMA-Intervention model to sales at CS, the steep and persisting increase can be expected over the next one year. On the other hand, we expect the rate of sales growth of supermarkets to be lagging and tied up constantly in the next 2016 year. Conclusions - Based on 2017 one-year sales forecasts for CS and supermarkets, we can yield the useful information for the development of CS and also for all retail trades. Future study is needed to analyze sales of popular items individually such as tobacco, banana milk, soju and so on and to get segmented results. Furthermore, we can expand sales forecasts to other retail trades such as department stores, hypermarkets, non-store retailing, so that comprehensive diagnostics can be delivered in the future.

• ALGAE
• /
• v.35 no.3
• /
• pp.225-236
• /
• 2020

Gymnodinium smaydae is a newly described mixotrophic dinoflagellate that feeds on only Heterocapsa spp. and Scrippsiella acuminata among 19 tested algal prey. It is one of the fastest growing dinoflagellates when feeding, but does not grow well without prey. To investigate its spatial-temporal distributions in Korean waters, we quantified its abundance in water samples that were seasonally collected from 28 stations along the Korean Peninsula from April 2015 to October 2018, using quantitative real-time polymerase chain reactions. This dinoflagellate had a wide distribution, as reflected by the detection of G. smaydae cells at 23 of the sampling stations. However, this distribution had a strong seasonality; it was detected at 21 stations in the summer and only one station in winter. The abundance of G. smaydae was significantly and positively correlated with chlorophyll a concentration as well as with water temperature. However, there were no significant correlations between the abundance of G. smaydae and salinity, concentrations of nutrients, or dissolved oxygen concentration. During the study period, G. smaydae was present when water temperatures were 7.6-28.0℃, salinities were 9.6-34.1, concentrations of NO₃ were not detectable-106.0 μM, and concentrations of PO₄ were not detectable-3.4 μM. The highest abundance of G. smaydae was 18.5 cells mL^-1 in the coastal waters of Jinhae in July 2017 when the chlorophyll a concentration was 127 mg m^-3 and water temperature was 23.8℃. Therefore, the spatial-temporal distribution of G. smaydae in Korean coastal waters may be affected by chlorophyll a concentration and water temperature.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.16 no.2
• /
• pp.63-74
• /
• 2013

This study suggests that some of the negative arguments related to naturalized plants raised in academic discussions are unreasonable through an analysis of trends in the academia's research on naturalized plants in South Korea. A total of 117 academic papers related to "naturalized plants" on the Korean Studies Information Service System (KISS) website were re-classified by space, the number of vascular plant species, the number of naturalized plant species, naturalization index (NI), and urbanization index (UI). Correlation between human interference and naturalized plant distribution, and between sizes of conservation areas and naturalized plant distribution were analyzed. According to the results, while there was a tendency between urban population and UI ($r^2$ = 0.70, p = .000), the number of visitors in national parks had no relation to either the NI or the UI (r = 0.028 and r = 0.013, respectively). Likewise, there was no correlation between national parks or conservation areas and naturalized plant distribution (r = 0.014, r = 0.17, respectively). The average NI and the UI of forest areas were approximately twice as low as those of national parks. In estimated regression equation, when one hypothesizes that the entire 4,952 taxa of plants growing in South Korea, the number of naturalized plants, combining paleo-naturalized plants and neo-naturalized plants, amounted to 2,398 taxa, 48.43%. In the academia, Korean Endemic Plants are less than one quarter of 4,952 taxa. Such results signify that, contrary to discussions in the academia, it is meaningless to distinguish between naturalized plants and native plants. In certain aspects, academic discussions on naturalized plants in Korea have proceeded in a manner similar to cultural exclusion by mono-culturalism in a multi-cultural environment.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.15 no.9
• /
• pp.1955-1964
• /
• 2011

With fast deployment of high-speed networks and various online services, the demand for massive content distribution is also growing fast. An approach that is increasingly visible in communication research community and in industry domain is peer-to-peer (P2P) networks. The P2P swarming technique enables a content distribution system to achieve higher throughput, avoid server or network overload, and be more resilient to failure and traffic fluctuation. Moreover, as a P2P-based architecture pushed the computing and bandwidth cost toward the network edge, it allows scalability to support a large number of subscribers on a global scale, while imposing little demand for equipment on the content providers. However, the P2P swarming burdens message exchange overheads on the system. In this paper, we propose a new protocol which provides confidentiality, authentication, integrity, and access control to P2P swarming. We implemented a prototype of our protocol on Android smart phone platform. We believe our approach can be straightforwardly adapted to existing commercial P2P content distribution systems with modest modifications to current implementations.

• The Journal of the Korea Contents Association
• /
• v.10 no.8
• /
• pp.38-50
• /
• 2010

In recent years, the number of users who are actively express their opinions about Internet articles is more and more growing up, as the use of cyber community such as weblog or Internet discussion board increases. In fact, it is not difficult to find an article with hundreds of comments in famous Internet discussion boards. Most of the weblogs or Internet discussion boards present comments in the form of list and do not yet support even the basic operation such as searching comments. In this paper, we analysed large sets of comments in Internet discussion board named AGORA. It was found that from the result that the distribution of comment writers follows power-law. So we suppose a new search structure of comments using skip lists. The main idea of our approach is to reflect the probabilistic distribution properties of the commenters following the power-law to the data structure. Our empirical results show that the proposed method performs more efficient in searching the nodes with fewer number of comparison operations than logN, which is the theoretical time complexity of general indexed structure such as B-trees or typical skip lists.

• Journal of Nutrition and Health
• /
• v.27 no.8
• /
• pp.828-836
• /
• 1994

A low level exposure experiment was conducted on growing rats to investigate the accumulation and organ distribution of protein bound cadmium compared with cadmium chloride. Male Sprague-Dawley rats were fed for 21days with one of the semisynthetic diets, which contains cadmium as either bovine liver- or kidney meal bound cadmium, cadmium chloride with uncontaminated liver meal or cadmium chloride without organ meal, in the levels of ca. 0.5, 1 and 1.5mg/kg diet, respectively. After 21days of exposure cadmium was accumulated in liver, kidney and gastrointestinal tracts depending upon cadmium levels in diet. Inspite of very low cadmium accumulation in whole blood, it tends also to increase with dietary cadmium levels. The blood cadmium concentration of animals fed organ meal containing diets was about 4-7 fold higher than that without organ meal, regardless of cadmium was intrinsically bound to protein or not. However, significant effects of organ protein on cadmium accumulation in liver, kidney and digestive tracts were not detectable, when cadmium was supplemented as cadmium chloride. On the other hands, animals fed diet containing ca. 1.5mg Cd/kg as organ bound cadmium retained more cadmium in liver, kidney and digestive tracts compared to cadmium chloride with organ meal, whereby the increase of cadmium concentration in kidney was greater then in liver. However, when the concentration of protein bound cadmium was<1mg/kg diet, organ bound cadmium was not significantly different from cadmium chloride in bioavailability and organ distribution. From this result it is suggested that the intestinal absorption of protein bound cadmium is influenced of the amount of cadmium bound in protein. When cadmium concentration in protein is relatively low, protein bound cadmium seems to be absorbed in the same way as cadmium ions are absorbed. However, when the concentration is high, at least a small amount of intact protein bound cadmium could be absorbed and accumulated selectively in kidney.

• Journal of the Korea Convergence Society
• /
• v.2 no.1
• /
• pp.1-6
• /
• 2011

The wide use of mobile devices such as smart phones makes the mobile commerce industry be growing-up rapidly. In mobile commerce security, how to secure a copyright of mobile contents and how to distribute it are of major concerns. The user can carry the smart phone regardless of the places. Thus the utilization of it is very high than that of personal computers. The USIM(Universal Subscriber Information Module) inserted in the smart phone binds the user with the device. This means that the smart phone can be used to represent the owner's identity. In this paper, we develop the mobile ID based digital signature scheme. We create the mobile ID by combining USIM with the user's random secret value. In addition, undeniable property of our signature scheme can make ID based applications such as mobile voting and mobile content distribution be possible with the smart phone.

• Journal of Ecology and Environment
• /
• v.33 no.2
• /
• pp.121-131
• /
• 2010

Betula platyphylla var. japonica and Betula ermanii segregate vertically at an elevation of approximately 1,850 m on Mt. Neko in Nagano Prefecture, Japan. B. platyphylla var. japonica and B. ermanii were the dominant species below and above this altitude, at which the mean-annual and growing-season air temperatures were $4^{\circ}C$ and $14.1^{\circ}C$, respectively. Based on a modification of Kira's warmth index which employs cumulative temperature represented as $^{\circ}C$ day, leaf unfolding in both species was observed to be initiated at $58^{\circ}C$ day and $169^{\circ}C$ day, respectively. In 1996, leaf unfolding was initiated on 18 May in B. platyphylla var. japonica (+/-6 days) and on 5 June in B. ermanii (+/-8 days), shortly after the last frost which occurred on 5 May 1995 above 1,850 m; below this elevation there was no risk of frost at the time. At elevations above 1,850 m, the unfolded leaves of B. platyphylla were damaged by late frost, while B. ermanii escaped injury because the leaves were still protected by winter buds. The optimum temperature for seed germination in both B. platyphylla and B. ermanii was $30^{\circ}C$. Temperature alternation from 10 to $30^{\circ}C$ and moist storage of seeds at $4^{\circ}C$ (stratification) prior to incubation increased germination rates in both species. The seedlings of B. ermanii had a greater survival rates than those of B. platyphylla var. japonica when planted above 1,850 m. Comparisons of the timing of leaf unfolding and the latest frost at a site appeared to be the main factors affecting the vertical distribution of these species.

• Journal of Oriental Neuropsychiatry
• /
• v.12 no.1
• /
• pp.169-182
• /
• 2001

The clinical study was carried out the 33 patients with insomnia who were treated in Daejeon University Oriental Hospital from 17 March 1997 to 12 May 2001. The results were summarized as follows. 1. The ratio of male and female was 10:23 and sleep initiation insomnia and sleep maintenance insomnia were the highest frequence(97%), the beginning of insomnia was frequent at 30s(27.3%). 2. Living accident by mental attack was the most inducing factor and many patients came to our hospital by way of west-neuropsychiatry(55.6%). 3. In admission period most of the patients were within 15 days(78.8%) and Liver-Qi- depression was the main cause and in classification of Four Human coporeal constitution the number of patients Sho-Eum-In(少陰人) was remarked mostly and in distribution of the prescription drugs of growing heart and warming gall bladder such as GUIBIONDAMTANG(歸脾溫膽湯) and ONDAMTANGGAMI (溫膽湯加味) were many, 4. Relatively most patients were well treated(69.7%) and insomnia was mainly caused by Anxiety Disorder and Depression and Hwabyoung and in the age distribution the highest frequence was 30s but we know insomnia appeared at all ages. 5. In distribution of the period of the clinical history was various and within 15 days were all improved and the treatments group of drug and acupuncture and aid treatments etc. and hypnotics was more improved than not used hypnotics treatments group but using hypnotics was temporal. I.

• Journal of Bio-Environment Control
• /
• v.8 no.4
• /
• pp.223-231
• /
• 1999

The one of basic functional conditions of suspended overhead sprayer, which is openly made use of irrigating on bedding plants in greenhouse, is to be kept the growing uniformity of bedding plants by making uniformly the spraying irrigation depending on the distribution of sprayed water. This study was performed to find out the optimum position of sector formed injection nozzle which is placed from the top of plant 0 the tip of the nozzle to keep spraying uniformity. The test of spraying distribution using a overhead sprayer, which was installed in a row of sector formed injection nozzles, was performed The measuring factor to represent spraying distribution was the water weight filled in each cup when the overhead sprayer was moving across the upside of the cups which were placed directly under the nozzles on keeping the distance from nozzle tip. The test results were as following , The standard mr of weights of each cup filled with spraying water was lower values at Position far from more than 60cm under nozzle tip. The driving speed variation of sprayer was not effected on spraying uniformity but the spraying water weight was inversely proportioned to the speed. To make best spraying uniformity, it was represented that the tip of the nozzle is positioned to keep the distance which the top of plants is placed at the second cross point of each injection sector of nozzles.