• Restorative Dentistry and Endodontics
• /
• v.45 no.3
• /
• pp.31.1-31.20
• /
• 2020

Matrix metalloproteinases (MMPs) are enzymes that can degrade collagen in hybrid layer and reduce the longevity of adhesive restorations. As scientific understanding of the MMPs has advanced, useful strategies focusing on preventing these enzymes' actions by MMP inhibitors have quickly developed in many medical fields. However, in restorative dentistry, it is still not well established. This paper is an overview of the strategies to inhibit MMPs that can achieve a long-lasting material-tooth adhesion. Literature search was performed comprehensively using the electronic databases: PubMed, ScienceDirect and Scopus including articles from May 2007 to December 2019 and the main search terms were "matrix metalloproteinases", "collagen", and "dentin" and "hybrid layer". MMPs typical structure consists of several distinct domains. MMP inhibitors can be divided into 2 main groups: synthetic (synthetic-peptides, non-peptide molecules and compounds, tetracyclines, metallic ions, and others) and natural bioactive inhibitors mainly flavonoids. Selective inhibitors of MMPs promise to be the future for specific targeting of preventing dentin proteolysis. The knowledge about MMPs functionality should be considered to synthesize drugs capable to efficiently and selectively block MMPs chemical routes targeting their inactivation in order to overcome the current limitations of the therapeutic use of MMPs inhibitors, i.e., easy clinical application and long-lasting effect.

• Journal of Korean Society of Forest Science
• /
• v.108 no.1
• /
• pp.59-66
• /
• 2019

This study was conducted to evaluate the effect of the synthetic forest road network by calculating the optimal road density and layout of the forest road network in order to construct the systematic road network in the forested area. For this, five comparative routes were additionally planed and compared through evaluation indicators. As a result, the optimum road density of the study site was estimated to be 18.4 m/ha, and the synthetic forest road network was the best in the four indicators such as average skidding distance, standard deviation of skidding distance, development index, and circuity factor. In addition, the synthetic forest road network was comparable to the main road network by about 4 %p in the timber volume available and potential area size for logging, but the construction cost of the road was about 20 %p lower. It showed a synthetic forest road network was better in terms of economy.

• International Journal of Computer Science & Network Security
• /
• v.22 no.5
• /
• pp.154-162
• /
• 2022

Digital marketing tools are actively used in managing the development of park and recreation complexes to familiarize the population with the objects of natural heritage. This article aims to empirically evaluate digital marketing tools for popularizing the park and recreational complexes. The methodology was based on the concept of ecosystem value of park and recreation complexes as a natural heritage site. These methods included: identifying and selecting websites with information about park and recreation complexes in Slovakia and Ukraine. structural analysis of the main channels of online details about natural parks. Assessing the current state of online identity of the studied sites from the perspective of Internet users. The results indicate that to manage the development of park and recreational complexes developed their driven official websites in the Internet space, on which sections structure the information with the allocation of data on tourism and recreational potential. The article identifies additional digital marketing tools for managing the development of park and recreation complexes, particularly social networks and tourist websites. There is a sufficient amount of information about tourist recreation sites within these natural parks and tourist routes. Among the main problems of the websites: the information on the websites is entirely textual, there is a lack of sufficient data on social networks, despite the created official pages, there is no video content, which was more attracted tourists and visitors, allowing a visual assessment of the tourist potential; there is a problem of many communication channels to present the natural heritage of the countries. The research proves that the website is the primary and most common digital marketing tool for natural heritage, structuring information about tourism potential and recreation.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.30 no.6D
• /
• pp.599-604
• /
• 2010

In this study, the value of travel time was estimated with reflecting the fuel cost according to travel distance. The main objective of this study is whether the addition of the fuel cost as a factor for route choice behavior is appropriate or not, through the stated preference survey. The route choice model was developed using SP survey technique with the consideration of level difference and the value of travel time, toll and fuel costs. Consequently, the fuel cost is identified as a main factor like travel time and toll cost in choosing routes from drivers' viewpoints. Nevertheless, since toll costs are recognized as out-of-pocket expenses whereas fuel costs as periodical expenses, it seems drivers are more sensitive to toll than fuel costs.

• Journal of the Korean Institute of Traditional Landscape Architecture
• /
• v.33 no.2
• /
• pp.49-57
• /
• 2015

The purpose of this study is to provide the visual landscape modelling on Josun royal tombs and surrounding. The visual landscape of traditional heritage is illustrated by the main view points of analysis. This analysis examines limited view points and cannot reflect a reality of environments. Nowadays various equipments and methodologies are developed for the visual landscape research. This study used new tools for analysis which are Sketch up (3D simulation) and mini helicopter (UAV). With those tools, this research examines not only view points of the analysis but also axis views and disincentive environments as a complex analysis. First of all, the research examined 3D modelling for the virtual simulation and drew coordinates and routes for the UAV operating. Secondly, UAV followed this routes and took linear and continuous views that are real scenes. As a result, it drew 3D simulation could illustrate and control the changing of environments such as the forest density and seasonal variations. Thus, comparing both of them shows efficiently landscape analysis. Thirdly, the study compared virtual and real landscape. Using this 3D modelling, this paper able to elaborate heritage environment and surrounding which omitted by view point analysis. Although this study has limitation practice and exercise on the field, the results and suggestions contribute to the various historic heritage managements and conservations. Moreover, it helps to explain the complex and dimensional landscape analysis.

• Journal of Korean Society of Transportation
• /
• v.23 no.5 s.83
• /
• pp.157-167
• /
• 2005

Seoul metropolitan public transport reform results in the introduction of the semi-public operation and distance-based fare policies. With implementation of these policies, public transport revenue allocation has been (will be) evolved very complicated because the existing revenue allocation issues have not only been clearly solved, which is generated by the combined relationship among Korea Railroad Corporation (KRC). Seoul Metropolitan Subway Corporation (SMSC). Seoul Metropolitan Rapid Transit Corporation (SMRTC), and Incheon Rapid Transit Corporation (IRTC), but also the revenue allocation problem between bus and urban railroad-related organizations need to be considered in this combined framework. On top of that. based on the future plans such as the private sector's railroad construction plan(s), the light rail transit construction plans of several local governments and the join of remained bus lines of Seoul metropolitan areas, it is understood that the revenue allocation among public transport operating organization will become one of main issues of operation organization as well as local and central governments. As a basic approach for revenue allocation of public transport operation organizations, the purpose of this paper is to propose an integrated model applicable to estimate degree of service contribution in passenger carriage in the combined public transport network. With a hypothesis that the complete electronic card system is deployed, this paper supposes every passenger's loading and alighting stations is recordable. Thereby, this paper limits research scope as to Seoul metropolitan railroad area since used route(s) between origin and destination stations can not be traceded because transfer stations each passenger path through is not recorded. Each model proposed in the paper is as follows: 1. a generalized cost reflecting passenger's transfer behavior; 2.a K path model for determining similar routes between O-D; 3.an assignment model for loading O-D trips onto the detected similar routes using Logit Model.

• Acta Via Serica
• /
• v.1 no.1
• /
• pp.95-104
• /
• 2016

The Silk Route in ancient times served as a link between the World's greatest civilizations and as a source of knowledge, art, religion and philosophy. This network of ancient caravan paths formed the first bridge between East and West, where two different civilizations came in contact with their respective cultural traditions and religious beliefs, as well as their scientific and technological achievements. One of the main routes of the Great Silk Route passed through the Karakoram, linking Kashgar with Kashmir and the Gandhara regions. The Karakoram Highway connects the Chinese province with Pakistan and follows the ancient Silk Route, which connected the Heartlands of Asia with the Western fringes and further beyond the entire continent of Europe. Evidences of the history of humankind, ranging from Pre-historic times to the spread of Buddhism from South Asia to China and the Far East, is depicted in the rocky cliffs on the waysides and on rough boulders scattered in the upper valley of the Indus River and its tributaries. The ancient trade routes also carried scholars, teachers, missionaries and monks of different beliefs and practices, who met and exchanged ideas. The Buddhists as well as Zoroastrians and other missionaries all followed the Silk Route, leaving permanent footprints of their passage. The ancient greater Gandhara is situated in the North-West of the Indian Sub-continent, with the steep mountain ranges of the Karakoram, the Pamir and the Hindu-Kush bordering it and the dry areas of Central Asia to its rear. A number of races from Central Asia migrated to Gandhara because of its mild climate and plentiful farm products and fruits. This area was an entry point of Western Culture into India and at the same times the exit point of Indian Culture, including Buddhism, to the West. In Gandhara, the diffusion of different cultures developed an art form, during the 1-7th centuries CE commonly known after its geographic name as "Gandhara Art". The Buddhism's route of introduction into China originated in Gandhara, then reached in Korea and Japan and other countries. The fame of Gandhara however, rested on its capital, "Taxila" which was a great centre of learning. From the time of the Achaemenians, down through Muslim period, Gandhara continued to establish and maintain a link between East & West, as shown by material evidences recovered from Taxila and other Buddhist centres of Gandhara during the course of archaeological excavations.

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.43 no.8 s.350
• /
• pp.47-58
• /
• 2006

Due to the movement of nodes, ad-hoc networks suffer from the problems such as the decrease of data delivery ratio, the increase of end-to-end delay, and the increase of routing overhead. The backup routing schemes try to solve these problems by finding the backup routes during the route discovery phase and using them when a route fails. Generally the backup routing schemes outperform the single-path routing schemes in terms of data delivery ratio, end-to-end delay, and routing overhead when the nodes move rapidly. But when the nodes don't move rapidly, the backup routing schemes generate more routing traffics than the single-path routing schemes because they need to exchange packets to find the backup route. In addition, when the backup route fails earlier than the main route, it can not use the backup route because in many backup route algorithms, the backup route is found only at the initial route discovery phase. RBR(Reactive Backup Routing Algorithm) proposed in this paper is an algorithm that provides more stable data delivery than the previous backup routing schemes through the selective maintenance of backup route and the backup route rediscovery. To do that RBR prioritize the backup routes, and maintain and use them selectively Thus it can also decrease the routing overheads. Also, RBR can increase data delivery ratio and decrease delay because it reestablishes the backup route when the network topology changes. For the performance evaluation, OPNET simulator is used to compare RBR with the single-path routing scheme and some of the well known backup routing schemes.

• Journal of the Korean Institute of Traditional Landscape Architecture
• /
• v.32 no.4
• /
• pp.37-49
• /
• 2014

This paper aims to interpret the transformation process of town plan of Gosan-up(高山), which was provincial administrative focus town in Josun dynasty, basing on morphological viewpoint. Morphological concepts, such as morphological frame, urban plan, kernel, colonization, route system, fixation line, fringe belt, plan unit & plan division, morphological period derived from the study of Conzen, M.R.G. and Caniggia, G. epidome district, break point, broken plot, urban fallow, privatization are adopted for the interpretation of urban form. Morphological period of Gosan can be divided in four ; formation of kernel & morphological structure, disintegration & redevelopment of the kernel, augmentative development of the kernel & formation of modern epidome district, outwards expanding of urbanized area, transition & reorganization of epidome district. Especially public leading projects such as construction of new regional connection road and public facilities such as myeon(township) office, agricultural cooperatives federation office, market, are main factors of morphological transformation of townplan. In the early stage, under the Japanese imperialism, construction of the new matrix route(Gosan-ro) through the kernel and followed planned routes gave way to disintegrating traditional areal plan unit and forming small block plan units in administrative facilities area. And linear plan units with commercial buildings were formed along the new matrix route and planned route adjacent to periodical market. In the latter stage, with development of public facilities, private sectors' large circulation institution and terminal outside the kernel with planned routes formed areal block based plan units with commercial and public buildings. And part of the spatial area with the linear plan unit were turned into urban fallow. With the transformation of town plan, new roads outside the kernel have substituted for traditional fixation line of waterway with road and topographical feature. Fringe belts were made successively along the new road and around the major intersections outside of existing urbanized area. Land use in fringe belts, constituting of outer locational tendency early on formation, was gradually replaced with commercial & business buildings.

• Journal of the Korean association of regional geographers
• /
• v.5 no.2
• /
• pp.119-132
• /
• 1999

The Korean Peninsula, jutting southward from the Asian mainland into the Pacific Ocean, is surrounded by numerous bays and islands on three sides. The study area of this research is the coastal area surrounding the Sacheon Bay, which is located in the mid-southern tip of the peninsula. Historically, the bay region took the role of the main gate leading to the western part of Kyung-nam Do(Province) due to the fact that the bay is the nearest coast to Chinju, the central city of the province. The Sacheon Bay had provided important sea routes from the old days until the early twentieth century. Because of the bay's sea routes, the bay region has been militarily of great significance. Recently, road/rail/highway/airplane transportation functions have become gradually increased but sea transportation function has been decreased in the region. As the Sacheon Bay was rich in fishery resources, dozens of fishing villages in the bay region depended on fishery and marine product industries for long years. But the inflow of the fresh water used to cause serious damage to the fishing industry in the bay region after a drainage canal from the Nam River was constructed in 1969. As a result, the industry has dwindled gradually for last decades. Recently, a couple of industrial parks were constructed along the coast and many manufacturing factories were built on the parks. It has been expected that many jobs lost in fishery and agriculture are replaced by new opportunities in industry. More than half of the workers employed in the parks' factories commute from the city of Chinju. It is asserted in this paper that the transportation, fishery, manufacturing, and tourism functions of the Sacheon Bay region are closely associated with. The characteristics of the region can be well understood through the functional changes and associations.