• Journal of the Mineralogical Society of Korea
• /
• v.15 no.2
• /
• pp.140-144
• /
• 2002

The sample environment at high temperature for the four circle diffractometer at HANARO in Korea Atomic Energy Research Institute is developed. The performance test was carried out for a structurally known sample through the high temperature experiment with this equipment. In this study we found out that the developed sample environment is stable for a long time experiment at over 900 K. By the neutron diffraction from a single crystal of $LiTaO_3$(phase transition temperature about 900 K) at 298 and 913 K, the lithium atomic positions at both temperatures and disordered state of lithium atom at high temperature were confirmed. These are hardly possible to determine by the conventional X-ray diffraction method.

• 한국기계연구소 소보
• /
• s.15
• /
• pp.25-35
• /
• 1985

During one revolution of a gear, the intensity of the gear-meshing noise or vibration will vary, depending upon the run-out in the pitch diameter of the gear. Here noise can be produced bu excentricity of the shaft with respect to the base circle and by pitch errors. According to the noise generated is clearly dependent on the force and the amount of energy expended in elastically straining the machine member. The purpose of this paper is to discuss the analysis of the noise and technical reduction of gear noise for machine tool.

• Bulletin of the Korean Chemical Society
• /
• v.27 no.10
• /
• pp.1609-1612
• /
• 2006

The determination of the boron isotopic ratio in solutions was achieved by means of a solid state track detector by using an alpha track. The neutron flux was optimized by using a Cd-foil to find the optimum conditions for counting the number of alpha tracks on the selected solid detector caused by the (n, $\alpha$) nuclear reaction of boron. The home-made multi-dot detector plate was utilized in this study to increase the reproducibility of the measurement by uniformly drying the boron solution within the marked circle area on the detector plate. The experimental results of this study verified that the $^{11}B/^{10}B $ isotopic ratio can be measured by observing the number of alpha tracks for different concentrated standard solutions with various isotopic compositions. This technique was applied to the determination of $^{10}B$ enrichment factor in a biological sample for a boron neutron capture therapy.

• Journal of the Korean Solar Energy Society
• /
• v.33 no.6
• /
• pp.62-69
• /
• 2013

In this paper, Korea Institute of Energy Research, building integrated renewable energy monitoring system that utilizes solar power generation forecast data forecast model is proposed. Renewable energy integration of real-time monitoring system based on monitoring data were building a database and the database of the weather conditions and to study the correlation structure was tailoring. The weather forecast cloud cover data, generation data, and solar radiation data, a data mining and time series analysis using the method developed models to forecast solar power. The development of solar power in order to forecast model of weather forecast data it is important to secure. To this end, in three hours, including a three-day forecast today Meteorological data were used from the KMA(korea Meteorological Administration) site offers. In order to verify the accuracy of the predicted solar circle for each prediction and the actual environment can be applied to generation and were analyzed.

• Journal of the Mineralogical Society of Korea
• /
• v.20 no.4
• /
• pp.351-356
• /
• 2007

The crystal structure of $Li(ND_4)SO_4$ was analyzed by X-ray and neutron diffraction methods. The crystal is a deuterated $Li(NH_4)SO_4$ and one of the ferroelectric materials with hydrogen atoms. The crystal is orthorhombic at room temperature, $P2_1nb$, with lattice parameters of $a=5.2773(5)\;{\AA},\;b=9.1244(23)\;{\AA},\;c=8.7719(11)\;{\AA}$ and Z=4. Neutron intensity data were collected on the Four-Circle diffractometer (FCD) at HANARO in Korea Atomic Energy Research Institute and X-ray date were given by Prof. Y. Noda of Tohoku University Japan. The structure was refined by full-matrix least-square to final R value of 0.070 for 1450 observed reflections by X-ray diffraction and to final R=0.049 for 745 observed reflections by neutron diffraction. With X-ray data we obtained only one hydrogen atomic position. However, not only all atomic positions of four hydrogen atoms at $NH_4$ but also the occupation factors of D and H were refined with neutron data. From this results we obtained the average chemical structure of this sample, $LiND_{3.05}H_{0.95}SO_4$.

• Korean Journal of Oriental Medicine
• /
• v.1 no.1
• /
• pp.209-244
• /
• 1995

The time therapy in oriental medicine is to reserch physiological activity and pathological variation with time, or time with disease. In that, this therapy is to research the development of disease, progress, diagnosis, treatment, and the meaning of preventive medicine. The theory of time therapy has been developed form heaven-human corresponding principle, and fourtimes of seasons is related with human life. After that, this theory affects in yin-yang five circle principle and organ-meridian match system. The independent development was formed later, but the origin has progressed for a logn times. in relation with time therapy, traditional acupuncture therory suggested five semen. In twenty century, the doctor rheinhold voll suggested energy exchange theory, this theory is based on time therapy, but has partial differance also too. His oppinion is this´ the energy present in the body has a circulation following the acupuncture teaching, i.e., the organs and their meridians are flooded in a certain sequence by this flowing energy. This maximum times of the organs are of physiologic and pathologic significance to man. In next time, we will discuss the indivisual theory in detail, and wil have comparison, and considering too.

• Journal of the Korean Geosynthetics Society
• /
• v.18 no.4
• /
• pp.53-61
• /
• 2019

It is well known there are a lot of undeveloped energy resource in the Arctic circle. As global warming enables the use of Arctic sea routes, the interest in Arctic resource development is increasing. Recently, polar neighbors and developed countries are actively promoting construction project in Arctic circle. However, the issue of environmental pollution caused by Arctic resource development has been raised. Today, environmental issues have a significant impact on the success of the project as well as on the costs of Arctic development projects. Therefore, it is necessary to secure a technology related to energy resource development and transportation for the Arctic resource project. In addition, the establishment of strategy for environmental impact assessment (EIA) is important. This paper shows the characteristics and procedures of EIA for developing Arctic resources, and reviews how to construct the systematically management of the necessary information. This system consists of a database required for environmental impact assessment and its application. The system is expected to be utilized for strategic development projects in the Arctic.

• Journal of the Korean Society for Marine Environment & Energy
• /
• v.5 no.4
• /
• pp.27-40
• /
• 2002

The circulation of sea water was simulated by two dimensional tide model using the main four tidal components and permanent current driven by inflow/outflow across open boundaries. According to the residt of tide model, the maximum speed of eastward flow on the Cheju Strait is twice higher than that of westward flow. According to the result of permanent current, the flow of permanent current showing semi-circle pattern in the southern part of Kojedo was due to variation of topography. According to the result of circulation model in the Cheju Strait, eastward flow entering in the southern waters from the Yellow Sea of Korea were dominant, but outflows westward were weak. These results suggest that it was difficult to move for suspended particulate matter into the Yellow sea from the southern waters through Cheju Strait.

• Journal of Aerospace System Engineering
• /
• v.8 no.4
• /
• pp.32-38
• /
• 2014

Sufficient energy charging during a day is essential for a solar-powered long-endurance aircraft. Variations of flight path that is superior to a basic circle path are sought in this study for more efficient charging. Flight path associated with roll and pitch attitudes are investigated. It seems that the pitch angle can play more important role than the roll angle for the solar charging efficiency. Thus, more energy charging is observed when the entire flight path is tilted toward the direction of the sun.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.35 no.6A
• /
• pp.585-593
• /
• 2010

Geographic routing has been considered as an efficient, simple, and scalable routing protocol for wireless sensor networks since it exploits pure local location information instead of global topology information to route data packets. Geographic routing requires the sources nodes to be aware of the location of sinks. Most existing geographic routing protocols merely assume that source nodes are aware of the locations of sinks. How can source nodes get the locations of sinks was not addressed in detail. In this paper, we propose a sink location service via circle path for geographic routing in wireless sensor networks. In this scheme, a sink sends a Sink Location Announcement (SLA) message along a circle path, and a source node sends a Sink Location Query (SLQ) message along a straight path that certainly passes through the circle path. By this way we can guarantee the SLQ path and SLA path have at least one crossing point. The node located on the crossing point of the two paths informs the source node the sink location. This procedure can correctly work in any irregular profile sensor networks such as network that has holes or irregular shape by some rules. Simulation results show that our protocol is superior to other protocols in terms of energy consumption and control overhead.