• Journal of Internet of Things and Convergence
• /
• v.8 no.1
• /
• pp.23-29
• /
• 2022

The product to be developed in this study is a heat recovery device which generates steam or hot water at high temperature and high pressure by heating water using exhaust gas from diesel engine, gas engine, gas turbine, etc. as an exhaust gas boiler off heat boiler(EGB) type for ship and power generation. The steam vapor or the created warm water is used as the power source required for the steerage heating and hot water facility or the HFO heating of the ship, and the turbine drive. The principle of waste heat boilers serves to heat water as high temperature exhaust gas with heat pass through the tube of the boiler. The heated water is a structure that is sent to a cabin or turbine device in the form of steam. In this study, the objective of this study is to maximize the efficiency by increasing the heat transfer surface by replacing the tube which is the heat transfer part of EGB with the plate tube.

• (The)Study of the Eastern Classic
• /
• no.35
• /
• pp.161-188
• /
• 2009

Confucianism's concept of Ye is ruled by the absolute principle of the universe on one hand, and by "the rules of Ye(節文)" and "the rules of ceremony(儀則)", the principle of relative articulation on the other hand. The realizations of the absolute principle of Ye is depending on its usage in everyday life which is fundamentally conditioned by time and space. Thus, Ye's usage can be maximized when the fundamental principle and the condition of its usage make a mutual harmony. Of course, Ye and Ak(樂) are doing complementary roles for each other, since Ye is a principle of a division and Ak is a principle of combining features. However, the essence of Ye can be figured out as the characteristics of mutual reciprocity among things of hierarchy between the classes. Not only in Modern one But also in the medieval society, Ye was not a one-sided force. The essence of Ye does not retain the interests of an individual and the power of a group. If so, the formal aspects of Ye had been distorted. Confucianism demands a strict morality and ethics of a normal person as well as of the ruler. The characteristics of Ye is democratic and open to the condition of time and space. Yegyo should be rooted in everyday lives and realized as a usualness. Therefore, Shirak was an inevitable feature of Yegyo. During the 16th and the 17th century, Ye insinuated into everyday lives of the public in the Korean society. Yulgok Yiyi(李珥)'s Haejuhyangyak(海州鄕約) was estimated as the exemplary feature of Shirak.

• Journal of the Computational Structural Engineering Institute of Korea
• /
• v.29 no.6
• /
• pp.529-538
• /
• 2016

The simplified plate theory is presented for static and free vibration analysis of power-law(P) and sigmoid(S) Functionally Graded Materials(FGM) plates. This theory considers the parabolic distribution of the transverse shear stress, and satisfies the condition that requires the transverse shear stress to be zero on the upper and lower surfaces of the plate, without the shear correction factor. The simplified plate theory uses only four unknown variables and shares strong similarities with classical plate theory(CPT) in many aspects such as stress-resultant expressions, equation of motion and boundary conditions. The material properties of the plate are assumed to vary according to the power-law and sigmoid distributions of the volume fractions of the constituents. The Hamilton's principle is used to derive the equations of motion and Winkler-Pasternak elastic foundation model is employed. The results of static and dynamic responses for a simply supported FGM plate are calculated and a comparative analysis is carried out. The results of the comparative analysis with the solutions of references show relevant and accurate results for static and free vibration problems of FGM plates. Analytical solutions for the static and free vibration problems are presented so as to reveal the effects of the power law index, elastic foundation parameter, and side-to-thickness ratio.

• Journal of the Korean institute of surface engineering
• /
• v.49 no.2
• /
• pp.166-171
• /
• 2016

Cathodic protection is widely recognized as the most cost effective and technically appropriate corrosion prevention methodology for the port, offshore structures, ships. When applying the cathodic protection method to metal facilities in seawater, on the surface of the metal facilities a compound of calcium carbonate($CaCO_3$) or magnesium hydroxide($Mg(OH)_2$) films are formed by $Ca^{2+}$ and $Mg^{2+}$ ions among the many ionic components dissolving in the seawater. And calcareous deposit films such as $CaCO_3$ and $Mg(OH)_2$ etc. are formed by the surface of the steel product. These calcareous deposit film functions as a barrier against the corrosive environment, leading to a decrease in current demand. On the other hand, the general calcareous deposit film is a compound like ceramics. Therefore, there may be some problems such as weaker adhesive power and the longer time of film formation uniting with the base metal. In this study, we tried to determine and control the optimal condition through applying the principle of cathodic current process to form calcareous deposit film of uniform and compact on steel plate. The quantity of precipitates was analyzed, and both the morphology, component and crystal structure were analyzed as well through SEM, EDS and XRD. And based on the previous analysis, it was elucidated mechanism of calcareous deposit film formed in the sacrificial anode type (Al, Zn) and current density (1, 3, $5A/m^2$) conditions. In addition, the taping test was performed to evaluate the adhesion.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.17 no.7
• /
• pp.86-91
• /
• 2016

To solve the problem of the excessive error caused by using a single value for the shielding effect of the neutral line of an electric power distribution line in the calculation of the voltage it induces in a telecommunication line, the general expression that was previously developed to reflect the mechanism of voltage induction by a distribution line with multiple grounds is employed in this paper to represent the relationship between the leakage current rates at each ground pole. In this way, the formula for calculating the shielding effect of the neutral line can be factorized against the unbalanced current flowing in the neutral line, which is the root current of induction. This shielding coefficient of the neutral line is not constant, but can vary when a range of induced voltages is generated in the whole power distribution line. The calculation method developed herein reduces the error rate to one tenth of that of the existing calculation result in the case of overestimation and increases it by 14% in the case of underestimation.

• Journal of Advanced Marine Engineering and Technology
• /
• v.40 no.7
• /
• pp.635-641
• /
• 2016

In order to drive a hybrid propulsion device which combines an engine and an electric propulsion unit, battery packs that contain dozens of unit cells consisting of a lithium-based battery are used to maintain the power source. Therefore, it is necessary to more strictly manage a number of battery cells at any given time. In order to manage battery cells, generally voltage, current, and temperature data under load condition are monitored from a personal computer. Other important elements required to analyze the condition of the battery are the internal resistances that are used to judge its state-of-health (SOH) and the open-circuit voltage (OCV) that is used to check the battery charging state. However, in principle, the internal resistances cannot be measured during operation because the parallel equivalent circuit is composed of internal loss resistances and capacitance. In most energy storage systems, battery management system (BMS) operations are carried out by using data such as voltage, current, and temperature. However, during operation, in the case of unexpected battery cell failure, the output voltage of the power supply can be changed and propulsion of the hybrid vehicle and vessel can be difficult. This paper covers the implementation of a high safety battery management system (HSBMS) that can estimate the OCV while the device is being driven. If a battery cell fails unexpectedly, a DC power supply with lithium iron phosphate can keep providing the load with a constant output voltage using the remainder of the batteries, and it is also possible to estimate the internal resistance.

• Journal of Ecology and Environment
• /
• v.45 no.3
• /
• pp.105-116
• /
• 2021

Background: The creation of the National Institute of Ecology began as a national alternative project to preserve mudflats instead of constructing the industrial complexes by reclamation, and achieve regional development. On the other hand, at the national level, the research institute for ecology was needed to cope with the worsening conditions for maintaining biodiversity due to accelerated climate change such as global warming and increased demand for development. In order to meet these needs, the National Institute of Ecology has the following objectives: (1) carries out studies for ecosystem change due to climate change and biodiversity conservation, (2) performs ecological education to the public through exhibition of various ecosystem models, and (3) promotes regional development through the ecological industry. Furthermore, to achieve these objectives, the National Institute of Ecology thoroughly followed the basic principles of ecology, especially restoration ecology, in the process of its construction. We introduce the principles and cases of ecological restoration applied in the process. Results: We minimized the impact on the ecosystem in order to harmonize with the surrounding environment in all the processes of construction. We pursued passive restoration following the principle of ecological restoration as a process of assisting the recovery of an ecosystem degraded for all the space except in land where artificial facilities were introduced. Reference information was applied thoroughly in the process of active restoration to create biome around the world, Korean peninsula forests, and wetland ecosystems. In order to realize true restoration, we pursued the ecological restoration in a landscape level as the follows. We moved the local road 6 and high-voltage power lines to underground to ensure ecological connectivity within the National Institute of Ecology campus. To enhance ecological diversity, we introduced perch poles and islands as well as floating leaved, emerged, wetland, and riparian plants in wetlands and mantle communities around the forests of the Korean Peninsula in the terrestrial ecosystem. Furthermore, in order to make the public aware of the importance of the intact nature, the low-lying landscape elements, which have disappeared due to excessive land use in most areas of Korea, was created by imitating demilitarized zone (DMZ) landscape that has these landscape elements. Conclusions: The National Institute of Ecology was created in an eco-friendly way by thoroughly reflecting the principles of ecology to suit its status and thus the impact on the existing ecosystem was minimized. This concept was also designed to be reflected in the process of operation. The results have become real, and a result of analysis on carbon budget analysis is approaching the carbon neutrality.

• The Korean Journal of Archival Studies
• /
• no.4
• /
• pp.63-91
• /
• 2001

This study is intended to examine the existing condition of records and archives management and seek its improvement and progress on a concrete model of Daejon Diocese as a kind of case study, because it is necessary to recognize the importance of records and archives management and to develop the records and archives management system. Daejon Diocese which has the catholic jurisdiction covering the areas of Daejon city and Chung Cheong Nam - Do province, celebrated the 40th anniversary of the diocese in 1998. At that, time, the authority of Daejon Diocese claimed to establish its church history institution and to plan the publication of "40 years history of Daejon Diocese". However, its publication could not be achieved until now for several reasons. Since my search for the cause of this situation, I immediately recognized that the lack of materials might be a common condition in almost all of the associations, especially with respect to management, preservation and access of the records and archives. The records in the archival repository of Daejon Diocese have been considerably lost because of the past intemperate destruction and these records have just piled for long time without any reasonable disposal programme. Therefore, in these poor conditions, it is inevitable to delay the publication of "40 years history of Daejon Diocese." This thesis deals with the archival arrangement and the ways of improvement by means of studying the records and archives management, as the essential issues. The archival arrangement based on the principle of provenance, the date of creation, and form division. The methods of improvement include the preservation environment, the scope of archives, archival staff, disposal and so on. Records have the legal and social value after being produced and they can remain as historical and cultural inheritances under the excellent condition of management and preservation. However, in examining the case of the management and preservation of records and archives in Daejon Diocese, I understand that it will need considerable time, man power, and financial cost in order to maintain the desirable level of records and archives management system Therefore, it is a important step for Catholic Daejon to recognize the necessity of the change over records and archives management.

• Journal of Korean Medical classics
• /
• v.29 no.3
• /
• pp.57-74
• /
• 2016

Subject : Treatment of acupuncture & moxibustion in Huangdineijing Objectives : Discover the principles and substances of acupuncture & moxibustion treatment of Huangdineijing Methods : The author reviewed the Huangdineijing: Suwen, Lingshu to gain a realistic sense of the facts and the medical book's contents that deal with the practices of acupuncture & moxibustion treatment for clinical praxis. Conclusions : 1. The acupuncture & moxibustion of Huangdineijing can be defined as follows. A treatment for correcting of meridian's drift by proper selection of surgical site, using suitable implementation and appropriate manipulation skill from a correct judgement of meridian's flowing through sensing the pulse for diagnosis when the meridian's flowing which come and go constantly driven by the tidal order of defensive Qi tactually appeared hard or soft caused by diseases, thus bring out the soft & gradual 50 laps circulation of nutrient Qi moderately driven by defensive Qi. 2. Today's acupuncture & moxibustion treatments greatly differ from those of Huangdineijing in that we do not know the substance of that treatment which is correcting of meridian's drift and do not obligatorily carry out feeling of the pulse for diagnosis which is a measure & judgement of meridian's flowing against a preliminary treatment in parallel with treatment so reduce use and power of that treatment. 3. I could form a list of general principle from the substances of acupuncture & moxibustion of Huangdineijing like as the flowing or fate of meridian Qi(tidally going in order of defensive Qi and nutrient Qi), deficiency or excess of Meridian flowing, comparing diagnosis before and after treatment, bring out the soft & gradual Qi. That was imposing "the concept of time" on recognition and treatment to human body.

• Journal of the Korean Institute of Gas
• /
• v.28 no.1
• /
• pp.53-58
• /
• 2024

Due to the development of industry and improvement of living standards, the amount of natural gas used in the world is constantly increasing, and related industrial facilities such as power plants, storage facilities, and supply pipelines are constantly increasing. Natural gas is a convenient and clean fuel that does not pollute the environment, but in the event of an accident due to leakage, it can cause human casualties, large-scale property damage, and negative effects on the global warming effect. In addition to the severe penalties under the Severe Disaster Punishment Act, it is necessary to ensure safety. Therefore, by applying the principle of laser-based absorption spectroscopy, we developed a long-range portable methane leakage gas detection system that can detect the concentration of methane leaking from a distance of up to 30 meters and verified its effectiveness.