• Weed & Turfgrass Science
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• v.5 no.3
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• pp.111-125
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• 2016

Cordgrass (Spartina spp.) is recognized as a highly invasive plant in estuaries throughout the world because of remarkable versatility and resiliency, significant reproduction, strong adaptability, rapid spreading, and vigorous growth. In this review, therefore, to provide insights on the effective management practices, the previous research works were summarized and discussed. Spartina spp. is a perennial halophyte, warm-season (C4) grass that reproduces both sexually through seeds and asexually by rhizomes. Management strategies for cordgrass have included various physical, biological, and chemical controls. Herbicides are usually the most cost-effective means of control. Currently, glyphosate, imazapyr, fluazifop and haloxyfop have been practically used. To improve the control efficacy, a combination of two more than methods (example, mowing-spraying) is needed to be applied consistently every year for at least 3 to 4 years and to be sprayed with enough dry time (>4-6 hr) at an early growth stage (before flowering). Consistently repeated application of same herbicide have to be avoided to prevent an unexpected emergence of herbicide-resistant lines. On the other hand, Spartina spp. have many positive functions for agricultural and eco-engineering purposes. Thus, we have to give more intensive research for effectively managing advantages and disadvantages of Spartina plantations.

• Korean Journal of Materials Research
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• v.9 no.3
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• pp.315-321
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• 1999

Metal matrix composites have been extensively studied because of their excellent characteristics for structural application. $Al_2O_3$ and SiC have been used as a common reinforcement owing to their good mechanical properties. However the manufacturing cost of these ceramic reinforcement is expensive, so the use of the composites has been restricted to special purposes. In this study, we tested the application possibility as a reinforcement of $Al_2O_3$-TiC powder synthesized by SHS(Self-propagating High-temperature Synthesis) process to Al alloy matrix composite. Also, $Al_2O_3$ short fibers were added with the synthesized powders in order to apply to the Al matrix hybrid composites. Squeeze infiltration casting process was used to make the composite with 25vol% of reinforcement. Microstructure and crystal structure were examined by SEM, OM and XRD, also the mechanical properties were studied by the compressive test and wear test.

• Pediatric Infection and Vaccine
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• v.22 no.3
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• pp.136-142
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• 2015

The Korean Society of Pediatric Infectious Diseases (KSPID) has participated in the task force team consisting of government authorities as well as civil medical experts and facilities to block the spread of Middle East Respiratory Syndrome in 2015. KSPID posted the "Middle East Respiratory Syndrome (MERS) Pop-up" in the homepage of The Korean Pediatric Society and The Korean Society of Pediatric Infectious Diseases. KSPID also released the "Guidelines for testing for MERS in children and adolescents" and the "Instructions for the Operation of National Safe Hospital" for children and adolescents in a timely manner. Such actions were aimed to prevent unnecessary anxieties, studies and isolation of pediatric patients with respiratory symptoms and signs caused by other common microbial etiologies as being suspected for MERS patients. This strategy relieved the doctors and parents from unnecessary fear and prevented the loss of unnecessary health care costs, and has proven to be a well-judged guideline and management protocol as evaluated after the final end of MERS outbreak. KSPID and its members should support the presence of pediatric infectious disease (PID) specialists in every medium size hospitals in Korea by developing the need for consultation fees for PID consultation in the hospital based practice and promoting the potential for cost savings related to prevention of health care associated infections and optimal prescription of antimicrobial agents. KSPID and its members need to approach and develop a communication plan to political decision makers to demonstrate and convince them of the importance of a PID specialist service.

• Journal of KIISE:Computer Systems and Theory
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• v.36 no.1
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• pp.26-32
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• 2009

The multi-level storage architecture has been widely adopted in servers and data centers. However, while prefetching has been shown as a crucial technique to exploit sequentiality in accesses common for such systems and hide the increasing relative cost of disk I/O, existing multi-level storage studies have focused mostly on cache replacement strategies. In this paper, we show that prefetching algorithms designed for single-level systems may have their limitations magnified when applied to multi-level systems. Overly conservative prefetching will not be able to effectively use the lower-level cache space, while overly aggressive prefetching will be compounded across levels and generate large amounts of wasted prefetch. We design and implement a hierarchy-aware lower-level prefetching strategy called PMS(Prefetching strategy for Multi-level Storage system) that applicable to any upper level prefetching algorithms. PMS does not require any application hints, a priori knowledge from the application or modification to the va interface. Instead, it monitors the upper-level access patterns as well as the lower-level cache status, and dynamically adjusts the aggressiveness of the lower-level prefetching activities. We evaluated the PMS through extensive simulation studies using a verified multi-level storage simulator, an accurate disk simulator, and access traces with different access patterns. Our results indicate that PMS dynamically controls aggressiveness of lower-level prefetching in reaction to multiple system and workload parameters, improving the overall system performance in all 32 test cases. Working with four well-known existing prefetching algorithms adopted in real systems, PMS obtains an improvement of up to 35% for the average request response time, with an average improvement of 16.56% over all cases.

• Korean Journal of Remote Sensing
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• v.24 no.4
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• pp.381-388
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• 2008

In the common practice of air-photographing measurement aerial-photogrammetric, the location of camera at the time of photographing is identified by performing aerotriangulation. However, installing ground-base station to enable aerotriangulation takes majority portion of a map making cost. Aerial-photogrammetric has shown a great improvement helped by steady upgrading in equipment and development in quantitative study. Aerotriangulation can be replaced by Direct Georeferencing, which uses GPS/INS to identify a camera location and to produce detailed information. An innovative technique replacing aerotriangulation, it has a disadvantage that base station has to be available in the area of photographing. The study intends to suggest a method applying VRS in GPS/INS aerotriangulation. Despite the fact that Direct Georeferencing is the innovated technique which substitutes existing aerotriangulation, it still need to install the ground-base station in GPS/INS aerotriangulation. GPS/INS data was analyzed with 4 different cases in order to accomplish the purpose of this study. In addition, in the thesis, it was approved that VRS can be utilized to make small-scale map as accurate as base station. This study is expected to improve the efficiency of work by showing that VRS can be used not only in base station but also enabling base station in the ground-access challenging area.

• Journal of the Society of Naval Architects of Korea
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• v.53 no.6
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• pp.503-513
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• 2016

In order to reduce the green-house gas exhaustion, International Maritime Organization (IMO) has been reinforcing carbon gas regulations. Due to the regulations, a lot of competitions for designing Eco ship in the shipbuilding industry are progressing now. It is faced with the necessity of reducing hull weight by combining automated systems for optimal compartment arrangement with hull structural design. Most researches on optimum structural design method have been consistently in progress and applied to minimize weight and cost of mid-ship section in preliminary ship design stage based on analytical structural analysis method on fixed compartment arrangement. In order to reduce design period and to improve international technical competitiveness by shortening the period of hull structural design and enhancing design accuracy, it has been felt necessity to combine optimized compartment arrangement with optimum design of ship structure based on the international regulations and rules. So in this study, the automated design algorithm for longitudinal members has been developed to combine automated algorithm of compartment arrangement with hull structural design system for oil tanker. The SeaTrust-Hullscan software developed by Korean Register is used to perform ship structural design for mother ship and selected design cases. The effect of weight reduction is verified with comparison of ship weight between mother ship and the cases suggested in this study.

• Food Science and Preservation
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• v.17 no.5
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• pp.571-580
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• 2010

We sought to define the main motivational factors promoting consumption of Prunus mume products. We surveyed both specialized high-volume consumers and public consumers, and focused on consumption of and preferences for Prunus mume and Prunus mume products. We investigated how products were preferentially consumed, purchase experience, purchase location, purchase price, consumption experience, factors important in a purchase decision, preference factors, dissatisfaction factors, consumption outlook, comments on new processed foods, and activation of consumption. A total of 534 responses were received and data were analyzed using the SAS program (Version 9.1) of the Frequency test; Chi-square test was used to detect significant factors. A greater percentage of high-volume(compared with low-volume) consumers processed personal products at home. The public consumer tended to buy commercial products. However, public consumers who were older, who had higher incomes, and who were heads of households, tended to both buy commercial products and to prepare foods at home. The common purchase methods used by high-volume consumers were internet and direct marketing, but the public consumer frequented department stores and hypermarkets. High-volume consumers observed that commercial products were expensive, and such consumers seemed to be particularly cost-sensitive. The decisive factor triggering purchase decisions in high-volume consumers was the geographical origin of the fruit, whereas the public consumer was more concerned with taste. In public, positive factors were that the product was good for health and had a pleasant taste. Some of those surveyed complained of a lack of variety in Prunus mume products and that the amount of Prunus mume in certain products was low. To promote and increase consumption, convenient-to-eat products with healthy images are needed.

• Journal of the Korea Convergence Society
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• v.12 no.5
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• pp.127-138
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• 2021

The aim of this study is to demonstrate interaction as a describable field and tries to understand interaction from the perspective of attributes, thus building a theoretical to help interactive designer understand this field by common rule, rather than waste huge time and labor cost on iteration. Since the concept of interaction language has been brought out in 2000, there are varies of related academical studies, but all with defect such as proposed theoretical models are built on a non-uniform scale, or the analyzing perspective are mainly based on researcher's personal experience and being too unobjective. The value of this study is the clustered resource of research which mainly based on academical review. It collected 21 papers researched on interaction paradigm or interaction attributes published since 2000, extracting 19 interaction attribute models which contains 174 interaction attributes. Furthermore, these 174 attributes were re-clustered based on a more unified standard scale, and the two theoretical models summarized from it are respectively focuses on interaction control and interaction experience, both of which covered 6 independent attributes. The propose of this theoretical models and the analyzation of the cluster static will contribute on further revealing of the importance of interaction attribute, or the attention interaction attribute has been paid on. Also, in this regard, the interactive designer could reasonably allocate their energy during design process, and the future potential on various direction of interaction design could be discussed.

• The Journal of Korean Academy of Prosthodontics
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• v.59 no.2
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• pp.164-172
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• 2021

Purpose: The purpose of this study was to analyze the level of interest that common Internet users have in dental implant using a Google Trends, and to compare the level of interest with big data from National Health Insurance Service. Materials and methods: Google Trends provides a relative search volume for search keywords, which is the average data that visualizes the frequency of searches for those keywords over a specific period of time. Implant was selected as the search keyword to evaluate changes in time flows of general Internet users' interest from 2015 to 2019 with trend line and 6 month moving average. Relative search volume for implant was analyzed with the number of patients who received National Health Insurance coverage for implant. Interest in implant and conventional denture was compared and popular related search keywords were analyzed. Results: Relative search volume for implant has increased gradually and showed a significant positive correlation with the total number of patients (P<.01). Interest in implant was higher than denture for most of the time. Keywords related to implant cost were most frequently observed in all years and related search on implant procedure was increasing. Conclusion: Within the limitations of this study, the public interest in dental implant was gradually increasing and specific areas of interest were changing. Web-based Google Trends data was also compared with traditional data and significant correlation was confirmed.

• Korean Journal of Environment and Ecology
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• v.33 no.4
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• pp.408-421
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• 2019

This study estimated and analyzed the incremental profits to compare the imported buff-tailed bumblebees, Bombus terrestris, and their pollination alternatives. A result of the analysis showed that the incremental profit, which is defined as the sales revenue minus the common production cost, was higher when using pollinator insects than when using the artificial pollination and that the incremental costs were lower when using domestic bumblebees or artificial pollination than when using imported bumblebees or honeybees. The incremental profits of each alternative were 46,801 million won for imported bumblebees, 47,170 million won for domestic bumblebees, 46,975 million won for honeybees, and 29,839 million won for artificial pollination. The incremental profit means the accounting profit that can be realized from each alternative. However, not all of the accounting profits can be attributed to pollen-mediated alternatives since they include potential costs such as imputed rent or normal profits. Considering the opportunity costs, which are the potential costs, it appears that the alternative of using imported bumblebees can lead to an economic loss. It means that fruit and vegetable farmers can expect additional economic profits if they choose other alternatives instead of using imported bumblebees.