• Journal of Korea Port Economic Association
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• v.36 no.4
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• pp.17-30
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• 2020

In the shipping industry, it is essential to engage in the preemptive prediction of freight rate volatility through market monitoring. Considering that freight rates have already started to fall, the loss of shipping companies will soon be uncontrollable. Therefore, in this study, factors affecting the freight rates of bulk carriers, which have relatively large freight rate volatility as compared to container freight rates, were quantified and analyzed. In doing so, we intended to contribute to future shipping market monitoring. We performed an analysis using a vector error correction model and estimated the influence of six independent variables on the charter rates of bulk carriers by Handy Size, Supramax, Panamax, and Cape Size. The six independent variables included the bulk carrier fleet volume, iron ore traffic volume, ribo interest rate, bunker oil price, and Euro-Dollar exchange rate. The dependent variables were handy size (32,000 DWT) spot charter rates, Supramax 6 T/C average charter rates, Pana Max (75,000 DWT) spot charter, and Cape Size (170,000 DWT) spot charter. The study examined charter rates by size of bulk carriers, which was different from studies on existing specific types of ships or fares in oil tankers and chemical carriers other than bulk carriers. Findings revealed that influencing factors differed for each ship size. The Libo interest rate had a significant effect on all four ship types, and the iron ore traffic volume had a significant effect on three ship types. The Ribo rate showed a negative (-) relationship with Handy Size, Supramax, Panamax, and Cape Size. Iron ore traffic influenced three types of linearity, except for Panamax. The size of shipping companies differed depending on their characteristics. These findings are expected to contribute to the establishment of a management strategy for shipping companies by analyzing the factors influencing changes in the freight rates of charterers, which have a profound effect on the management performance of shipping companies.

• Weed & Turfgrass Science
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• v.4 no.4
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• pp.405-412
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• 2015

Forty schools having natural turf playgrounds were investigated by on-spot investigation and oral interviews with relevant school officials to find out basic information on turfgrass management practices of school playgrounds in Gyeonggi province. Average area of playground was $3,890m^2$ per school and $12m^2$ per student. Ninety five percent of turf playgrounds were managed by school staff and ninety percent of schools spent less than 5 million won per year for turf management. The difficulties in turfgrass management were considered as a major challenge for the schools, followed by turfgrass management cost. Among the management practices, school officials pointed out weed management as the most difficult work, followed by irrigation. The average number of fertilization and mowing was 2 and 6 times per year, respectively. About the half of playgrounds were irrigated only when there was wilting symptom. Zoysiagrass was the most popular choice for the school playgrounds and only three school playgrounds were established with pop-up irrigation system. Fourteen school playgrounds had good turf quality but the rest of school playgrounds had inadequate turf quality requiring minor or full renovation.

• Journal of the Korea Safety Management & Science
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• v.17 no.1
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• pp.93-101
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• 2015

The demand from customers on better products and systems seems to be ever increasing. To meet the demand, the systems are becoming more and more complicated in terms of both scale and functionality, thereby requiring enormous effort in the development. One bright spot of this trend is that such effort has been the driving forces of the remarkable advancement in modern systems development. On the other hand, safety issues appear to be critical in many large-scale systems such as transportation and weapon systems including high-speed trains, airplanes, ships, missiles/rockets launchers, and so on. Such systems turn out to be prone to a variety of faults and thus the resultant failure can cause disastrous accidents. For the reason, they can be referred to as safety-critical systems. The systems failure can be attributed to either random or systemic factors (or sometimes both). The objective of this paper is on how to reduce potential systemic failure in safety critical systems. To do so, a proper system design is pursued to minimize the risk of systemic failure. A focus is placed on the fact that complex systems have a lot of complicated interfaces among the system elements. To effectively handle the sources of hazards at the complicated interfaces and resultant failure, a method is developed by utilizing a design structure matrix. As a case study, the developed method is applied in the design of train control systems.

• Journal of Evidence-Based Herbal Medicine
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• v.2 no.1
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• pp.25-31
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• 2009

The origin and description of the Herba Plantaginis was contemporarily analyzed (family names, scientific names, target regions, preparation, etc.) by comparison to enormous literature in addition to the external features written in the existing books on traditional Korean medicine. Also, galenical description were analyzed in connection with external morphology, internal morphology, microscopy and five senses. The official documents and ancient documents of other countries were reviewed. The technical books on herbage, published in the country and other countries, were compared with each other. Also, on-the-spot surveys were made to learn specialists' know-how. The description of the collected drugstuffs were analyzed in connection with external morphology (size, color, etc.), internal morphology and microscopy. The results of this study can be applied to the publicity and education of galenical test agencies; the effective management of foods and drugs; the improvement of public medical service; the publicity of galenical safety.

• Journal of the Korean Geotechnical Society
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• v.26 no.5
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• pp.49-55
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• 2010

The large scale rock falling had occurred on 22nd February, 2007 in the Cheongbuldong valley area of Seoraksan National Park, and the visiting pass had been closed for a while. Similar cases of rock falling have occurred in the latest years according to a great variety of crack, joint, weathering of solid rock and surface water caused by a recent climatic change in the Seoraksan National Park. In this study, rock falling energy was estimated and the movement of rockslide was analysed based on detailed investigation on large scale rockslides occurring at the spot 80 m high from the bottom of the valley. From analysing results, the effective management method for rock falling was proposed. The method could minimized the dangerous factors with no change of natural environment of the National Park.

• Fisheries and Aquatic Sciences
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• v.15 no.4
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• pp.313-316
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• 2012

Two unrecorded species of the snapper, Lutjanus malabaricus (296.0 mm standard length [SL]) and L. stellatus (350.0 mm SL) belonging to the family Lutjanidae, were first collected from the western coastal waters of Jeju Island, Korea. L. malabaricus is characterized by having a dark marking on the upper half of the caudal peduncle, a band of vomerine teeth that does not protrude posteriorly at the middle, and nine anal soft rays. Compared to its Korean relative, L. malabaricus is distinguishable by having rows of scales that run obliquely in the dorsal-posterior direction above the lateral line (vs. parallel to the lateral line in L. argentimaculatus). L. stellatus can be identified by the absence of wavy blue lines on the head (vs. many blue lines in L. rivulatus) and presence of a white spot above the lateral line (vs. a black blotch on the lateral line in L. rivulatus). We propose new Korean names, "Jin-hong-tung-dom" and "Huin-jeom-tung-dom," for L. malabaricus and L. stellatus, respectively.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.6
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• pp.954-959
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• 2020

This study aimed to verify the effectiveness of rescue apparatus, that can capture crabs using external stimuli such as food and electricity, without relying on divers. In this study, a microcomputer-based controller and an IC-device-based controller were developed, and spot inspection was conducted using 20 modules and 30 sea urchin removal modules. Accordingly, 58, 18, 17, and 74 sea urchins were introduced in the first, second, third and fourth experiments, respectively. The result of evaluating the lure of each removal mechanism, based on the catch per unit effort, with an electrical stimulus was 1.1 (32/10), with a feeding stimulus was 3.4 (100/29), and with electrical and feeding stimuli was 3.5 (35/10).

• The Journal of the Korea Contents Association
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• v.9 no.11
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• pp.465-474
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• 2009

To measure the amount of nonpoint source pollution, some efforts are tried to utilize satellite imagery. But, as the factors for water models do not relate with the landcover categories for satellite imagery, satellite imagery are adapted to roughly classified thematic map or used only for the image interpretation. The purpose of this study is to establish the landcover categories of satellite imagery to relate with the water models. To establish the categories of the landcover for the water models, it was investigated to get main factors of water flow models for the nonpoint source pollution and to review the existing study and the classification system. For this result, it was convinced that the basic unit on the nonpoint source pollution, landcover coefficients of SCS Curve Number, the crop factor of Universal Soil Loss Equation, Manning's roughness coefficients are the useful parameters to extract information from the satellite imagery. After the setup the categories for the landcover classification, it was finally defined from the consultation of the water model specialist. Woopo wetland watershed was selected to the study area because it is a representative wetland in Korea and needs the management system for nonpoint source pollution. There were used Landsat ETM Plus and SPOT-5 satellite imagery to assess the result of the image classification.

• Journal of Korea Multimedia Society
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• v.18 no.4
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• pp.546-556
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• 2015

Since the concept of software engineering was first used in 1968 by NATO Science Committee, a lot of research work and improvements have been made on software development methodology and software quality control, but they still fall short of ensuring successful development of small and medium scale software systems. Under these circumstances, Center for Software Engineering (CSE) at National IT Industry Promotion Agency(NIPA) has been conducting studies on quality control methodologies of software visualization well-suited for small and medium scale software systems, and also working on the systemization and quantification of software quality control. In this paper, we attempt to scope on the software development management of domestic and foreign small and medium-sized enterprises that are lying in the blind spot, compared to large enterprises with well-organized software development systems. In particular, based on software visualization that CSE is pursuing for small and medium-sized developers, we propose a practical quality control methodology well-suited for small and medium scale projects, and a low-cost quality control management tool by combining open-source quality control tools. Our proposal is expected to induce developers' mind change in SI-specialized small and medium-sized software enterprises, increase their profits and improve customer satisfaction through project quality control.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.26 no.6
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• pp.872-880
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• 2022

This paper present a design and implementation of a Contents Management System (CMS) to be integrated into a game that uses a Digital Game-based Learning (DGBL) approach for helping tourists learn about tourism spots as a part of the Package Tour Application. In terms of design, this paper shows a system architecture that consists of a database to store the game's content such as tourism spot information, score and question configuration, score history, et cetera, a web application to manage the content and a Rest API to delivers the content to the mobile game. Meanwhile, in terms of implementation, MySQL database and PHP programming language are used. Moreover, a time response performance evaluation is conducted which resulted in between 0.77 s to 1.4 s from CMS to the database. Once successfully integrated with the game, the CMS will allow the game to be played on multiple tours simultaneously, without having to rebuild the game for every package tour group.