• Fisheries and Aquatic Sciences
• /
• v.12 no.4
• /
• pp.331-338
• /
• 2009

This study presents physiological rates of respiration and excretion, clearance rate, and assimilation efficiency of the ark shell Scapharca broughtonii, determined during 2007 from specimens collected in Gamak Bay on the south coast of Korea. Physiological parameters were measured monthly under static, laboratory controlled conditions with ambient conditions, and measurements were performed seasonally in order to estimate scope for growth and its probable sources of variation. Temperature directly influenced respiration and excretion. Clearance rates showed a tendency to be low during May-August, which is a period of gametogenesis. Assimilation efficiency was not significantly different seasonally and was independent of the concentration of chlorophyll a. The scope for growth was negative during high-temperature months (July-August), reflecting the high temperature and low clearance rate, and had its highest positive values during spring and autumn. The energy budget or growth potential of bivalves has been applied to other economically important species. Data on the physiological parameters and scope for growth of S. broughtonii obtained in this study will be used to assess the carrying capacity for ark shell cultivation.

• The Bulletin of The Korean Astronomical Society
• /
• v.42 no.1
• /
• pp.49.1-49.1
• /
• 2017

In order to investigate the origin of multiple stellar populations in the halo and bulge of the Milky Way, we have constructed chemical evolution models for the low-mass proto-Galactic subsystems such as globular clusters (GCs). Unlike previous studies, we assume that supernova blast waves undergo blowout without expelling the pre-enriched gas, while relatively slow winds of massive stars, together with the winds and ejecta from low and intermediate mass asymptotic giant branch stars, are all locally retained in these less massive systems. We first applied these models to investigate the origin of super-helium-rich red clump stars in the metal-rich bulge as recently suggested by Lee et al. (2015). We find that chemical enrichments by the winds of massive stars can naturally reproduce the required helium enhancement (dY/dZ = 6) for the second generation stars. Disruption of these "building blocks" in a hierarchical merging paradigm would have provided helium enhanced stars to the bulge field. Interestingly, we also find that the observed Na-O anticorrelation in metal-poor GCs can be reproduced, when multiple episodes of starbursts are allowed to continue in these subsystems. Specific star formation history with decreasing time intervals between the stellar generations, however, is required to obtain this result, as would be expected from the orbital evolution of these subsystems in a proto-Galaxy. The "mass budget problem" is also much alleviated by our models without ad-hoc assumptions on star formation efficiency and initial mass function.

• The Bulletin of The Korean Astronomical Society
• /
• v.43 no.1
• /
• pp.46.1-46.1
• /
• 2018

In order to investigate the origin of multiple stellar populations in the halo and bulge of the Milky Way, we have constructed chemical evolution models for the low-mass proto-Galactic subsystems such as globular clusters. Unlike previous studies, we assume that supernova blast waves undergo blowout without expelling the pre-enriched gas, while relatively slow winds of massive stars, together with the winds and ejecta from low and intermediate mass asymptotic-giant-branch stars, are all locally retained in these less massive systems. We find that the observed Na-O anti-correlations in metal-poor GCs can be reproduced when multiple episodes of starbursts are allowed to continue in these subsystems. A specific form of star formation history with decreasing time intervals between the stellar generations, however, is required to obtain this result, which is in good agreement with the parameters obtained from our stellar evolution models for the horizontal-branch. The "mass budget problem" is also much alleviated by our models without ad-hoc assumptions on star formation efficiency and initial mass function. We also applied these models to investigate the origin of super helium-rich red clump stars in the metal-rich bulge as recently suggested by Lee et al. (2015). We find that chemical enrichments by the winds of massive stars can naturally reproduce the required helium enhancement (dY/dZ = 6) for the second-generation stars. Disruption of proto-globular clusters in a hierarchical merging paradigm would have provided helium enhanced stars to the bulge field.

• Journal of the Korean housing association
• /
• v.26 no.5
• /
• pp.113-121
• /
• 2015

Several housing improvement programs for low-income have done by Ministry of Health & Welfare, Ministry of Trade, Industry & Energy, Ministry of Security and Public Administration, Ministry of Environment, and Ministry of Land, infrastructure and Transport up to now. Each program practiced separately based on each agency's function and territory, but there are also negative opinion on beneficiary duplication, beneficiary omission, and the inefficient execution of the government budget. This study analyzes the housing improvement programs of each agency on the aspects of coordination, and suggests the integration system with coordination and delivery system. We selected 3 indexes such as similarity, integration effect and availability for integration system and analyzed the effects of integrated programs into one based on cost, repair effect and management. We proposed that the similar housing improvement programs of each agency should be coordinated for integration. But it is not easy to integrate similar programs into one program, therefore similar programs which support the house owner are needed to integrate into housing benefit except same beneficiary who owned own house.

• Journal of Korean Society of Forest Science
• /
• v.90 no.3
• /
• pp.346-354
• /
• 2001

This study was conducted to investigate the status and problems, and suggest the proper improvement of provincial rotation hunting system in Korea. There were many problems in recently provincial rotation hunting system, such as, difficulty of budget interiority, low participation rate of hunters, low specialization degree of officers on their job, and extremity of illegal capture of wildlife by the absence of wildlife manager. The municipal hunting system, which have many merits, such as, increase of hunters' participation and income of municipality, creation of engagement, and prohibit of illegal capture of wildlife would be suggest for the improvement of hunting system.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2009.09a
• /
• pp.677-694
• /
• 2009

While the budget has been allocated more for repairs and reinforcements, casualties are gradually increased due to slope disaster. Slope disaster causes road damaged as well as casualties. It also causes significant social and economic loss. The measurement device, which is installed inside ground of slope like inclinometer, has the high loss rate when slope is being slided. The electric type and the vibrating wire type have low durability because of corrosion. To cover the demerit of the present slope monitoring, the measurement method using the Multi-Antenna GPS has been developed. The Multi-Antenna GPS has been installed in the local slope as the regular monitoring system for slope. Although the initial cost of the Multi-Antenna GPS for installation is high, the additional cost is low. So it is the suitable method for large slope. The regular monitoring system using the Multi-Antenna GPS is the suitable measurement method for watching slope collapse, which is occurred widely, because it is economical, has high durability, and collects data with high resolution.

• Korea Journal of Hospital Management
• /
• v.16 no.4
• /
• pp.111-130
• /
• 2011

The purpose of this study is to find moderating effects of re-use intention by trust factors between patients satisfaction and hospital images. Survey a general hospital in Seoul was performed, and a total of 202 questionnaires has been analyzed. Result of multiple regression analysis are verified moderating effects by trust factors with hospital image and re-use intention(F=8.223**). And patient satisfaction and re-use intention are verified moderating effects by trust factors(F=4.255*). In addition, classify them into high trust group and low trust group by median split method, even if there are felt the equal level of satisfaction or image that high trust group will be re-visit the hospital better than low trust group. As a result, trust factors must consider different level from satisfaction or image, it is necessary that hospitals will be prepare to improve the trust.

• Journal of Sensor Science and Technology
• /
• v.14 no.2
• /
• pp.116-124
• /
• 2005

In this paper range measurement systems are designed using an ultrasonic sensor and a camera. An ultrasonic sensor provides the range measurement to a target quickly and simply but its low resolution is a disadvantage. We tackle this problem by employing a camera. Instead using a stereoscopic sensor, which is widely used for 3D sensing but requires a computationally intensive stereo matching, the range is measured by focusing and structured lighting. In focusing a straightforward focusing measure named as MMDH(min-max difference in histogram) is proposed and compared with existing techniques. In the method of structure lighting, light stripes projected by a beam projector are used. Compared to those using a laser beam projector, the designed system can be constructed easily in a low-budget. The system equation is derived by analysing the sensor geometry. A sensing scenario using the systems designed is in two steps. First, when better accuracy is required, measurements by ultrasonic sensing and focusing of a camera are fused by MLE(maximum likelihood estimation). Second, when the target is in a range of particular interest, a range map of the target scene is obtained by using structured lighting technique. The systems designed showed measurement accuracy up to 0.3[mm] approximately in experiments.

• Korean Journal of Childcare and Education
• /
• v.16 no.6
• /
• pp.1-17
• /
• 2020

Objective: The purpose of this study is to examine whether the 'Ordinance for Guaranteeing Children's Right to Play' is has been implemented well and investigate play practice in elementary school. Methods: For this study, a survey was conducted on 319 elementary school teachers in Jeollanam-do. Results: First, elementary school teachers' perception of the enactment of the 'Ordinance on Children's Right to Play' is high. And their perception is positive about the effect of the 'Ordinance on Children's Right to Play'. Second, among the roles of the Office of Education, play-related training and club support were relatively low. The role of the elementary school director was relatively low in the analysis and disclosure of play performance. Third, the time that children mainly play in school is the middle play time. The sufficiency and safety of play spaces differed by region. Fourth, the contents to be added to the 'Ordinance' are securing play space, budget support, and mandatory play time. Conclusion/Implications: In the future, 'Ordinance on Children's Right to Play' should go through a process of improvement so that children's play is realized as a right.

• Journal of the Korean Society of Visualization
• /
• v.21 no.1
• /
• pp.110-118
• /
• 2023

Characterizing the extensional rheological properties of non-Newtonian fluids is crucial in many industrial processes, such as inkjet printing, injection molding, and fiber engineering. However, educational institutions and research laboratories with budget constraints have limited access to an expensive commercial extensional rheometer. In this study, we developed a custom-made extensional rheometer using a CO₂ laser cutting machine and 3D printer. Furthermore, we utilized a smartphone with a low-cost microscopic lens for achieving a high spatial resolution of images. The aqueous polyethylene-oxide (PEO) solutions and a Boger fluid were prepared to characterize their extensional properties. A transition from a visco-capillary to an elasto-capillary regime was observed clearly through the developed rheometer. The extensional relaxation time and viscosity of the aqueous PEO solutions with a zero-shear viscosity of over 300 mPa·s could be quantified in the elasto-capillary regime. The extensional properties of the solutions with relatively small zero shear viscosity could be calculated using a smartphone's slow-motion feature with increasing temporal resolution of the images.