• The Journal of Natural Sciences
• /
• v.8 no.1
• /
• pp.61-69
• /
• 1995

It is hard to synthesize pure $BaTiO_3$ from $BaCO_3$ and $TiO_2$ in solid reaction for the activity of BaO and secondary phase. For this reason, the wet chemical techniques have been studied. Starting material which was used in these methods were expensive and the properties of powder which was synthesized in same defined. So, some process have been studying again to improve soild reaction method. This study which was one of those was to defin the forming mechanism of $Ba_2TiO_4$ and to control some condition of $Ba_2TiO_4$. The synthesis temperature of $BaTiO_3$ in solid reaction was near $1120^{\circ}C$. The quantity and forming temperature of $Ba_2TiO_4$ could be controlled by atmosphere heat treatment. $Ba_2TiO_4$ was related to expansion in Ba-rich region of $BaTiO_3$. $BaTiO_2O_5$ and $BaTiO_3O_7$ was reason to expand in Ti-rich region. The dielectrics of $CeAIO_3$ which was synthesized and sintered in reduction atmosphere and $BaTiO_3$ system were affected by $CeO_2$ which was formed for the decomposition of $CeAIO_3$ heat treatment in air.

• Journal of Ginseng Research
• /
• v.30 no.4
• /
• pp.206-211
• /
• 2006

To investigate mycorrhizal infection by arbuscular mycorrhizal fungi(AMF), samples of fine lateral roots were taken from the wild ginseng(Panax ginseng C.A. Meyer) naturally growing at various locations in Korea. Mycorrhiazal infections were studied by cleaning the root samples and staining fungal hyphae with frypan blue. Wild ginsengs for this study were graded by an appraisal committee consisting of 12 experts of Korea Mountain Ginseng Association. Following five quality groups were recognized: Heaven group(pure natural), Earth group (from seeding of wild ginseng), Man group(from seeding or seedlings of wild ginseng with slight environmental modification), unmarketable, and imported wild ginseng. Morphology of AMF was typical Paris-type which shows intracellular hyphal coils with rare vesicles and lack of arbuscules. Average infection rate of individual wild ginsengs was 58.3% and showed no differences among five quality groups. When portions of fine roots were quantified for mycorrhizal infection, 18.7% of the total length of the primary and secondary roots were infected by AMF. Wild ginsengs from Gyeonggi Province(84.2%), and from mountains lower than 1,200 meters above sea level(about 70%) showed higher infection rate, while the ginseng from Gyeongbuk Province(27.8%) had lower rate. Wild ginsengs at older age showed lower infection rates.

• 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.

• Economic and Environmental Geology
• /
• v.54 no.6
• /
• pp.767-785
• /
• 2021

World-class magnesite deposits are developed in the Dashiqiao mineralized district of the Jiao-Liao-Ji Belt in China. This belt extends to the northern side of the Korean Peninsula and hosts major magnesite deposits in the Dancheon region of North Korea. Magnesite ores from the Pailou deposits in the Dashiqiao district is classified into pure magnetite, chlorite-magnetite, chlorite-talc-magnetite, and dolomite groups depending on the constituent minerals. According to the result of petrographic study, magnesite was formed by the alteration of dolomite, and, talc, chlorite, and apatite were produced as late-stage alteration minerals that replaced the magnesite. Fluid inclusions observed in magnesite are a liquid-type inclusion, with a homogenization temperature of 121-250 ℃ and a salinity of 1.7-22.4 wt% NaCl equiv. The chlorite geothermometer, indicating the temperature of hydrothermal alteration, is 137~293 ℃, slightly higher than the homogenization temperature of fluid inclusions, and the pressure is calculated to be less than 3.2 kb. For magnesite mineralization in the study area, the initially formed-dolomite was subjected to replacement by Mg-rich fluid to form a magnesite ore body, and then it was enriched through regional metamorphism and hydrothermal alteration. It seems that altered minerals such as talc were crystallized by Si and Al-rich late-stage hydrothermal fluids. These results are similar to the genetic environments of the Daeheung deposit, a representative magnesite deposit in North Korea, and it is believed that the two deposits went through a similar geological and ore genetic process of magnesite mineralization.

• Journal of the Daesoon Academy of Sciences
• /
• v.22
• /
• pp.345-385
• /
• 2014

The object of this thesis is to consider the meaning of sincerity(誠), reverence(敬) and faith(信) through Cha gyungseok's historical record. Cha gyungseok(車京石, 1880-1936) is a key disciple of Kang Jeungsan Sangjenim(姜甑山, 1871~1909) to whom Cha kyungseok has begun to follow since 1907, completing his wandering around Yeonghak-gye(英學契), Iljin-hoe(一進會) and Cheondo-gyo(天道敎) after the loss of his father[Cha Jikoo(車致九), 1851-1894] in Tonghak peasants revolution. To examine the meaning of sincerity, reverence and faith as cardinal points in Daesoonjinrihoe(大巡眞理會) creed, this research has taken note of Cha kyungseok's sincerity, reverence and faith who is said to be thought of himself as a head of Reconstruction Work for the Tonghak spitit's resolution of grievances, despite the Sangjenim's intention of using him for different usage due to his sincerity, reverence and faith. Especially, emphasis was given to the illumination of Cha gyungseok's change of sincerity, reverence and faith through closely reviewing his life prior to the encounter with Sangjenim, the process of following Sangjenim and his whereabouts after the ascension of Sangjenim. In addition, through Jeonkyeong(典經), this research also examines Cha kyeong seok's sincerity, reverence and faith along with his ambition contained in that sincerity, reverence and faith. Up to his ascension, Sangjenim has never saved his advice on Cha gyungseok's ambition. Leaving Sangjenim's advice behind, Cha gyungseok moves on to become a head of the Reconstruction Work for the Tonghak spitit's resolution of grievances without deserting the dream of being the Son of Heaven. Although, he showed his prowess as a religious sect leader called Bocheon-gyo boasting its 6 million believers and as a provisional emperor of the country named Sikuk, he ends his life as a head for the Resolution of grievances of kings, princes, generals and premiers due to the change of faith on Sangjenim and interruption of Japanese Imperial Government, without accomplishing his dream. The feature of past disciples suggests the direction of cultivation for our cultivators. Through Cha gyungseok's sincerity, reverence and faith, we could look back upon the meaning of sincerity, reverence and faith and conclude that a real sincerity, reverence and faith is the heart-mind trying to participate in Reconstruction Work of Heaven and Earth with a pure mind, contrary to the one coming out of greed.

• SUVANNABHUMI
• /
• v.6 no.1
• /
• pp.107-135
• /
• 2014

Cham identities which are socially constructed and multilayered, display their markers in a variety of elements, including homeland attachment to the former Kingdom of Champa, religion, language and cultural traditions, to mention a few. However, unlike other contemporary diasporic experience which binds the homeland and the host country, the Cham diaspora in Cambodia has a unique pattern as it seems to have no voice in the political and economic spheres in Vietnam, its homeland. The relations between the Cham in Cambodia and Vietnam seem to be limited to cultural heritages such as Cham musical traditions, traditional clothing, and the architectural heritage. Many Cham people have established networks outside Cambodia with areas of the Muslim world, like Malaysia, Indonesia, southern Thailand and the Middle Eastern countries. Pursuing education or training in Islam as well as working in those countries, especially Malaysia has become a way for the Cham to widen their networks and increase their knowledge of particularly, Islam. Returning to Cambodia, these people become religious teachers or ustadz (Islamic teachers in the pondok [Islamic boarding school]). This has developed slowly, side by side with the formation of their identity as Cham Muslims. Among certain Cham, the absence of an ancient cultural heritage as an identity marker has been replaced by the Islamic culture as the important element of identity. However, being Cham is not a single identity, it is fluid and contested. Many scholars argue that the Cham in Cambodia constitute three groups: the Cham Chvea, Cham, and Cham Bani (Cham Jahed). The so-called Cham Jahed has a unique practice of Islam. Unlike other Cham who pray five times a day, Cham Jahed people pray, once a week, on Fridays. They also have a different ritual for the wedding ceremony which they regard as the authentic tradition of the Cham. Indeed, they consider themselves pure descendants of the Cham in Vietnam; retaining Cham traditions and tending to maintain their relationship with their fellow Cham in Central Vietnam. In terms of language, another marker of identity, the Cham and the Cham Jahed share the same language, but Cham Jahed preserve the written Cham script more often than the Cham. Besides, the Cham Jahed teaches the language to the young generation intensively. This paper, based on fieldwork in Cambodia in 2010 and 2011 will focus on the process of the formation of the Cham identity, especially of those called Cham and Cham Jahed.

• Journal of the Daesoon Academy of Sciences
• /
• v.46
• /
• pp.33-68
• /
• 2023

Simwudo (尋牛圖), known as Ox Seeking Pictures, originated in the 11th-12th century and have consistently played a guiding role in the teachings of various religions in East Asia. Some Korean religions that emerged during modern times conveyed their teachings through depictions of ox seeking or herding. Among them, Daesoon Jinrihoe stands out as a representative religion. The belief system of this particular religion elucidates its distinct doctrine and worldview by reimagining Simwudo, into a new set of six panels (seven or nine panels in some variations). The Simwudo of Daesoon Jinrihoe differs from that of Buddhism, particularly in its treatment of meditation (禪), both in terms of context and significance. While they share similarities in the aspect of ox-seeking, the Buddhist Simwudo symbolizes human nature, whereas the Simwudo of Daesoon Jinrihoe represents the great Dao of Heaven and Earth propagated by Kang Jeungsan and brought into completion by Jo Jeongsan. In the Buddhist context, the subject of the search is the Ox, signifying the restoration of a deluded human's pure nature in order to achieve personal salvation and in some version of Simwudo, reenter society to perform salvific actions for others. On the other hand, in the Simwudo of Daesoon Jinrihoe depicts the process of a human attaining immortality and following the teachings of Jeungsan and Jeongsan. This culminates in the final image which is the redemption of the world. The final phase of the Buddhist Simwudo, depending on the version, is either enlightenment (personal salvation) or reentering society to perform salvific actions (as a bodhisattva), whereas the Simwudo of Daesoon Jinrihoe show the simultaneous achievement of the perfection of humanity and the redemption of the world. This distinction highlights the fundamental differences between the Simwudo of these two distinctly different religious traditions. These differences arise from the contrasting purposes pursued by Buddhism and Daesoon Jinrihoe.

• Journal of the Mineralogical Society of Korea
• /
• v.27 no.1
• /
• pp.17-30
• /
• 2014

Waste cement generated from recycling processes of waste concrete is a potential raw material for mineral carbonation. For the $CO_2$ sequestration utilizing waste cement, this study was conducted to obtain basic information on the aqueous carbonation methods and the characteristics of carbonate mineral formation. Cement paste was made with W:C= 6:4 and stored for 28 days in water bath. Leaching tests using two additives (NaCl and $MgCl_2$) and two aqueous carbonation experiments (direct and indirect aqueous carbonation) were conducted. The maximum leaching of $Ca^{2+}$ ion was occurred at 1.0 M NaCl and 0.5 M $MgCl_2$ solution rather than higher tested concentration. The concentration of extracted $Ca^{2+}$ ion in $MgCl_2$ solution was more than 10 times greater than in NaCl solution. Portlandite ($Ca(OH)_2$) was completely changed to carbonate minerals in the fine cement paste (< 0.15 mm) within one hour and the carbonation of CSH (calcium silicate hydrate) was also progressed by direct aqueous carbonation method. The both additives, however, were not highly effective in direct aqueous carbonation method. 100% pure calcite minerals were formed by indirect carbonation method with NaCl and $MgCl_2$ additives. pH control using alkaline solution was important for the carbonation in the leaching solution produced from $MgCl_2$ additive and carbonation rate was slow due to the effect of $Mg^{2+}$ ions in solution. The type and crystallinity of calcium carbonate mineral were affected by aqueous carbonation method and additive type.

• Journal of the Mineralogical Society of Korea
• /
• v.28 no.1
• /
• pp.39-49
• /
• 2015

Recently, carbon capture and storage (CCS) techniques have been globally studied. This study was conducted to use waste cement powder as an efficient raw material of mineral carbonation for $CO_2$ sequestration. Direct aqueous carbonation experiment was conducted with injecting pure $CO_2$ gas (99.9%) to a reactor containing $200m{\ell}$ reacting solution and the pulverized cement paste (W:C = 6:4) having particle size less than 0.15 mm. The effects of two additives (NaCl, $MgCl_2$) in carbonation were analyzed. The characteristics of carbonate minerals and carbonation process according to the type of additives and pH change were carefully evaluated. pH of reacting solution was gradually decreased with injecting $CO_2$ gas. $Ca^{2+}$ ion concentration in $MgCl_2$ containing solution was continuously decreased. In none $MgCl_2$ solution, however, $Ca^{2+}$ ion concentration was increased again as pH decreased. This is probably due to the dissolution of newly formed carbonate mineral in low pH solution. XRD analysis indicates that calcite is dominant carbonate mineral in none $MgCl_2$ solution whereas aragonite is dominant in $MgCl_2$ containing solution. Unstable vaterite formed in early stage of experiment was transformed to well crystallized calcite with decreasing pH in the absence of $MgCl_2$ additives. In the presence of $MgCl_2$ additives, the content of aragonite was increased with decreasing pH whereas the content of calite was decreased.

• Journal of the Korean earth science society
• /
• v.28 no.3
• /
• pp.298-310
• /
• 2007

Intercomparison between eight radiative transfer codes used for the studies of COMS (Communications, Ocean, and Meteorological Satellite) in Korea was performed under pure molecular, i.e., Rayleigh atmospheres in four shortwave fluxes: 1) direct solar irradiance at the surface, 2) diffuse irradiance at the surface, 3) diffuse upward flux at the surface, and 4) diffuse upward flux at the top of the atmosphere. The result (hereafter called the H15) from Halthore et al.'s study (2005) which intercompared and averaged 15 codes was used as a benchmark to examine the COMS models. Uncertainty of the seven COMS models except STREAMER was ${\pm}4%$ with respect to the H15, comparable with ${\pm}3%$ of Halthore et al.'s (2005). The uncertainty increased under a large $SZA=75^{\circ}$. The SBDART model generally agreed with the H15 better than the 6S model, but both models in the shortwave infrared region were equally good. The direct solar irradiance fluxes at the surface, computed by the SBDARTs of four different users, were different showing a relative error of 1.4% $(12.1Wm^{-2})$. This reason was partially due to differently installing the wavelength resolution in the flux integration. This study may be useful for selecting the optimum model in the shortwave region.