• Journal of the Korean Applied Science and Technology
• /
• v.35 no.4
• /
• pp.975-984
• /
• 2018

Fast pyrolysis bio-oil has unfavorable properties that restrict its use in many applications. Among the main issues are high acidity, instability, and water and oxygen content, which give rise to corrosiveness, polymerization during storage, and a low heating value. Esterification and azeotropic water removal can improve all of these properties. A 500 g of Quercus mongollica which grounded 0.8~1.4 mm was processed into bio-oil via fast pyrolysis for 2 seconds at $550^{\circ}C$. The esterification consists of treating pyrolysis oil with a high boiling alcohol like n-butanol at $70^{\circ}C$ under reduced pressure (100 hPa). All products are analyzed for water mass fraction, viscosity, higher heating value, pH, FT-IR and GC/MS. The water mass fraction can be reduced by 91.4 % (from 31.5 % to below 2.7 %), the viscosity by 65.8 % (from 36.5 to 12.5 cP) and the higher heating value can be increased by 96.8 % (from 3,918 to 7,712 kcal/kg), the pH by 1.3 (from 2.7 to 4.0). FT-IR and GC/MS analysis indicated that labile acids, aldehydes, ketones and lower alcohols were transformed to stable target products. Using this approach, the water content of the pyrolysis oil is reduced significantly. These improvements should allow the utilization of upgraded pyrolysis liquids in standard boilers and as fuel in CHP (Combined heat and power) plants.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.39 no.2
• /
• pp.61-67
• /
• 2019

This study was conducted to investigate the effect of supplementary feeding levels on livestck and forage productivity and grazing intensity in Elk stags (Cervus canadensis). A fifteen 2-year-old Elk stags about 195 kg were randomly assigned to one of three dietary treatments (five animals per treatment). The dietary treatments consisted of a feeding concentrate of 1.0% of body weight (T1), 1.5% of body weight (T2) and 2.0% of body weight. Total dry matter intake (TDMI) was increased with increased with an increasing supplementary feeding levels. Average daily gain (ADG) were significantly increased with an increasing supplementary feeding levels (p<0.05) and reached a maximum on July and was lower in spring than autumn. The velvet antler production was no differences among treatment groups. Forage productivity of pasture and crude protein content were highest on May and decreased thereafter, however, crude fiber content was the reversed. The grazing intensity of Elk stags was increased in spring (38 to 59 head per ha) than summer and autumn (13 to 32 head per ha). The average grazing intensity of Elk stags ranged from 21 to 34 head per ha, which is affected by supplementary feeding levels. This result suggests that feeding supplementary diet at 1.5 % of body weight was needed to maintain the stable wight gain in antler growing periods and control the proper grazing intensity of Elk deer stags.

• Korean Journal of Heritage: History & Science
• /
• v.48 no.2
• /
• pp.120-141
• /
• 2015

This paper is a preliminary study of architectural characteristics of Jangdae (general's podium), which shows one of the technical changes in fortification of Joseon Dynasty. As a facility for commands of generals and training for officers and men, it was located inside a fortress. Although it is not certain when the first Jangdae was built, the number of them dramatically increased around 18th century. Since the top priority function of the Jangdae was the prospect, it was installed at the hilly spot with open architecture. In addition, the open structure of Eupseong fortress towers on the riverside banks could simultaneously offer the functions as viewing around and Jangdae. Since Jangdae was also a place for military drills and reviews of soldiers, a wide podium was positioned at the front to muster the soldiers. This feature was standardized in the space organization of Jangdae in Joseon, and a mere podium was installed unless the topographic restrictions allows enough space. On the other hand, as a place for a commander, the hierarchy of the Jangdae was revealed through a variety of architectural characteristics. The hierarchy was assigned to the commander's space through the altitude difference, and diverse ornaments were added to show a sense of class. The floor plan of the Jangdae building can be largely categorized into rectangle and square, and the typical sizes of the former are $5{\times}4$ Kans (traditional measuring unit between two columns) and $3{\times}2$ Kans. Out of these two types, buildings of $5{\times}4$ Kans were found in flat land and eupseong fortresses with large space, and the relatively smaller ones of $3{\times}2$ Kans in mountain fortresses. All buildings of square floor plan had $3{\times}3$ Kans style, and the center Kan was twice wider than the side Kan to make the central space wide. It seems that the purpose was to secure the interior space of the upper story because the center Kan accounts for the floor area of the upper story. Some Jangdae's had internal story to form overhead space. The multi-roofed tower style with eaves attached to the upper and lower story is found exclusively in Jangdae. The buildings shows the Onkanmulim style which extends Naejinju (inner column) of the lower story to be the Byeonju (outer column) of the upper story, and the log-framed floor in the upper floor was structured by inserting the Changbang (connecting beam) between the Naejinju's and joining the log frames. In addition, the towers in eupseong fortresses had log-framed floor in the upper floor by setting up the high Nuhaju (column underneath a roof) and joining Cheongbang to the upper part of the column while it cannot be regarded as multi-roofed because only the upper part has a roof.

• Korean Journal of Heritage: History & Science
• /
• v.49 no.1
• /
• pp.84-97
• /
• 2016

One of the assimilation policies of Japanese imperialism for the permanent domination in the colonial Joseon is the theory of integration of Japan and Joseon. The theory of integration of Japan and Joseon is a logic that Joseon (Korea) and Japan (Wae) were connected to the same ancestor on the basis of ancient myths. Also it is the assimilation ideology to justify the Colonial rule of those days through the objectification of historical identity or affinity of political and cultural relations of ancient Korean peninsula and Japan (Wae). Japan reorganized our history to meet the colonial point of view, as part of the assimilation policies based on the theory of integration of Japan and Joseon. On the other hand Japan attempted to objectify them through archaeological research and the reinterpretation of the historical remains. The survey, reinterpretation and tourist of the historic sites in historic cities such as Gyeongju and Buyeo were promoted in this context. In particular, the Buyeo, a capital of Baekje, was emphasized upon the close relevance and affinity between Sabi, Baekje and ancient Asuka (飛鳥) in Japan through research and reinterpretation on the Historic Sites. Based on them, Historic Sites Tourism was conducted by reconstructed historic sites toward the colonial Korean. In addition, after the Sino-Japanese war in 1937, Japan tried to realize the politics of space by upgrading and idealizing Buyeo as homeland or Shinto (神都) related to Japanese ancient mythology of the Asuka culture. This paper investigated in what context research, reinterpret and tourist of the historic sites progressed on Buyeo area and how it had soaked through the general public in the Japanese colonial era. First, it is on historic sites. Historic sites research on Buyeo area made an attempt by Sekino Tadashi in 1909 for the first time and the re-excavation of the old burial mounds and temple sites during the Japanese colonial period. Sekino set up a cultural relationship and influences between the ancient China (梁), Korea (百濟) and Japan (倭). Also, he emphasized that Sabi, Baekje largely received influence of Chinese culture and Baekje and Japan Asuka culture had closely relations and affinity. These views had been consistent during the Japanese colonial period. Second, it is the reinterpretation on Historic sites. Buyeo Historic Sites Preservation Society (Buyeo Gojeok Bojonhoe) was established in 1915 and Osaka Kintaro, curator of Baekje exhibition hall redefined the relationship between ancient Japan and Baekje as perspective of the assimilation ideology through the post contextual interpretation. In particular, they emphasized on the close relevance between Baekje's Historic sites and Japan, through the reinterpretation of Nakhwaam, Goransa and Cheongmasanseong. Third, it is the tourist on Historic sites. Buyeo Historic Sites Preservation Society played a leading role in Tourist on Historic sites at the Buyeo region. The main tourist destinations and course were restructured through a reinterpretation on the historic sites. Japan would like to show Buyeo as ideology area, homeland of ancient Japanese culture, toward the Koreans under Japanese colonial era. Thus, research, reinterpretation, and tourism on Historic sites were promoted while they were closely related to each other. The promoting body was Joseon Chongdokbu and pro-Japanese interest group. It's point was 'made' and 'shown' by the eyes of others and a rediscovery of Buyeo as representational space of colony.

• Journal of the Korean Applied Science and Technology
• /
• v.35 no.4
• /
• pp.985-994
• /
• 2018

Bio-heavy oil for power generation is a product made by mixing animal fat, vegetable oil and fatty acid methyl ester or its residues and is being used as steam heavy fuel(B-C) for power generation in Korea. However, if the fuel supply system of the fuel pump, the flow pump, the injector, etc., which is transferred to the boiler of the generator due to the composition of the raw material of the bio-heavy oi, causes abrasive wear, it can cause serious damage. Therefore, this study evaluates the fuel characteristics and lubricity properties of various raw materials of bio-heavy oil for power generation, and suggests fuel composition of biofuel for power generation to reduce frictional wear of generator. The average value of lubricity (HFRR abrasion) for bio-heavy oil feedstocks for power generation is $137{\mu}m$, and it varies from $60{\mu}m$ to $214{\mu}m$ depending on the raw materials. The order of lubricity is Oleo pitch> BD pitch> CNSL> Animal fat> RBDPO> PAO> Dark oil> Food waste oil. The average lubricity for the five bio-heavy oil samples is $151{\mu}m$ and the distribution is $101{\mu}m$ to $185{\mu}m$. The order of lubricity is Fuel 1> Fuel 3> Fuel 4> Fuel 2> Fuel 5. Bio-heavy oil samples (average $151{\mu}m$) show lower lubricity than heavy oil C ($128{\mu}m$). It is believed that bio-heavy oil for power generation is composed of fatty acid material, which is lower in paraffin and aromatics content than heavy oil(B-C) and has a low viscosity and high acid value, resulting in inhibition of the formation of lubricating film by acidic component. Therefore, in order to reduce friction and abrasion, it is expected to increase the lubrication of fuel when it contains more than 60% Oleo pitch and BD pitch as raw materials of bio-heavy oil for power generation.

• Journal of Dairy Science and Biotechnology
• /
• v.37 no.2
• /
• pp.115-128
• /
• 2019

Lactic acid bacteria obtained from traditional Kimchi were selected on the basis of their caseinolytic activity and lactose usability and examined for availability as a starter in probiotic activity. Thirty-two strains were selected as lactic acid producing bacteria in BCP agar, and two strains (KC23 and KF26) with more than 90% resistance for both acid and bile salts were selected. The two strains were identified as L. plantarum (KC23) and L. paracasei (KF26) by API 50 CHL system and 16S rRNA sequence analysis. L. plantarum (KC23) was finally selected based on its biochemical characteristics for lactose and raffinose usability. Free tyrosine content increased rapidly in 10% skimmed milk medium, from $24.1{\mu}g/mL$ after 8 h to $43.9{\mu}g/mL$ after 16 h. Additionally, the caseinolytic clear zone of 12 mm of L. plantarum (KC23) was greater than the 9 mm zone of commercial L. acidophilus CSLA. The bacterium exhibited mesophilic growth and yielded $8.9{\times}10^8CFU/mL$ when incubated at $37^{\circ}C$ for 12 h at pH 4.25. Moreover, L. plantarum KC23 exhibited antibacterial activity as it formed a clear zone of 8-13 mm for the 5 pathogens. Adherent activity was 2.23 fold higher than that of LGG. The acidity of 10% skimmed milk fermented for 12 h was 0.74%.

• Korean Journal of Heritage: History & Science
• /
• v.41 no.2
• /
• pp.5-25
• /
• 2008

Seoul's community beliefs originated from the ritual performed by the shrines affiliated to each government office in the Joseon Dynasty. Lower branches of government officials were assigned to perform these rituals. Generally, these shrines were called Bugundang(府君堂). Records show that Bugundang(府君堂) was generally one to three units and enshrined the portrait of Bugun(府君), the worshipped, inside. According to historical records, the worshipped were mostly General Choi Young(崔瑩將軍) or Madame Song(宋氏夫人). In fact, however, each Bugundang(府君堂) worshipped different persons. Some of the worshipped were historical characters from the Goryeo Dynasty or the founding period of Joseon Dynasty, Guan Yu(關羽) and Zhuge Liang(諸葛孔明) that became gods after the Japanese Invasion of 1952, Wanggun(王建), Dangun(檀君), General Nam Yi(南怡將軍), Kim Yoo Shin(金庾信), Lim Gyeong Up (林慶業), King Gongmin(恭愍王), King Taejo(Lee Sung Gye, 太祖 李成桂), Joban(趙?) who is one of the supporters of the foundation of Joseon Dynasty, Sir Hong(洪氏大監) and his women who appear in the legend of Nanhansanseong(南漢山城) area, and many other historical figures. It is difficult to compare the rituals of these shrines from community Gut(Shaman ritual) performances of Seoul. According to historical records, Gut and ceremony coexisted in rituals. As time passed, these rituals spread as the community Beliefs of commoners and have been transmitted in the context of Seoul's cultural change. This study examined the existence of affiliated shrines of local government offices in the Joseon Dynasty and discussed the cases of Jangchung-dong Gwanseong Shrine(將忠洞 關聖廟), Bangsan-dong Seongje Shrine(方山洞 聖帝廟), and Seobinggo Bugundang(西氷庫 府君堂) to trace the succession of rituals at these shrines as folk customs of commoners. Bangsan-dong Seongje Shrine(方山洞 聖帝廟) spread to the public as Gwanwoo(關羽), who was considered the god of soldiers, transformed into the god of merchants along with historical transition. It clearly shows the process as to how merchants from a certain region developed a community religion. Jangchung-dong Gwanseong Shrine(將忠洞 關聖廟) is Bugundang(府君堂) of the soldiers of Nampyoug(南營). As the ritual was succeeded by a ritual group called Yeoungsinsa(永信社), composed of nearby residents, it was naturally spread and succeeded by the residents in local community. Seobinggo Bugundang(西氷庫 府君堂) was related to the changes in the historical background of ice gathering in the late Joseon Dynasty.

• Korean Journal of Heritage: History & Science
• /
• v.51 no.2
• /
• pp.78-91
• /
• 2018

Sangjogam, located in Goseong, Gyeongsangnam-do, was designated as Natural Monument #411, because of its diverse geological heritage, such as fossils, ripple marks, dykes, and columnar joints. In the area, Byeongpungbawi, with its beautiful columnar joints vertical to the bedding plane of the underlying sedimentary rocks and spectacular coastal view, was named after its overall shape reminiscent of a huge folding screen. The purpose of this study was to investigate the formation process of the columnar joints using the anisotropy of magnetic susceptibility (AMS) method. AMS measurements showed that the k1 and k3 values representative of directions of the long and short axes of a magnetic particle at each point strongly clustered, and the oblate magnetic foliation structure in Byeongpungbawi developed during sill-type intrusion rather than lava flow. In summary, Byeongpungbawi was produced by sill-type intrusion along the bedding plane of the underlying sedimentary layer, and the subsequent formation of columnar joints was accompanied by the cooling and contraction of intruding rhyolite magma. This study potentially provides a basic research tool in understanding the formation mechanism of columnar joints which are widely distributed in southern Korea.

• Korean Journal of Heritage: History & Science
• /
• v.39
• /
• pp.59-93
• /
• 2006

Wolseong in Gyeongju is a historic fortress site of Silla constructed under the reign of Pasanisageum that played politically and militarily important roles. The moat surrounding Wolseong had a function of protecting the fortress in wartimes but became a part of gardening in the unified Silla era. Lots of relics have been excavated from Wolseong moat since 1985. Among them a great number and kinds of convex roofing tiles are regarded as invaluable sources to show different aspects of Silla, from its earlier time through to the unified and on. Roofing tiles were widely used for national buildings such as royal palaces, temples and fortresses and even for other popular architecture and have been dug out a lot more than any other relics. Research on them, however, has been done poorly. Vigorous study is in progress with increasing number of roofing tiles coming from many recent excavations, though it has been limited to the studies on general genealogy of patterns and manufacture processes. Thus this essay seeks to find which are dongbeomwas, roofing tiles of a same mold, out of convex tiles with the pattern of a unilobed lotus flower dug out of Wolseong moat. It also attempts to identify dongbeomwas by examining detail characteristics of roofing tiles which have been confusingly termed as yusawa, similar roofing tiles, or donghyeongwa, roofing tiles of the same shape. The significance of identifying dongbeomwas could be emphasized by various facts resulting from researches on dongbeomwas; the ways to identify them correctly, their time sequence and their excavated sites. In conclusion, dongbeomwas were identified out of many kinds of convex tiles. If they were excavated from the same site, they share some common features. The sites where they were dug out also tell what changes were made with passage of time and what relations they had with neighboring Anapji. Since roofing tile molds haven't been found yet, the only way to identify dongbeomwas is to examine details of roofing tiles. Dongbeomwas excavated in Wolseong moat help to discuss the time of each district of it. Meanwhile it should be noted that the term 'dongbeomwa' be used only after exact examining.

• Economic and Environmental Geology
• /
• v.53 no.6
• /
• pp.687-694
• /
• 2020

Two oxidizing agents (KMnO4, H2O2), and one neutralizing agent (NaOH) were applied to evaluate Mn removal in mine drainage. A Mn2+ solution and artificial mine drainage were prepared to identify the Fe2+ influence on Mn2+ removal. The initial concentrations of Mn2+ and Fe2+ were 0.1 mM and 1.0 mM, respectively. The injection amount of oxidizing and neutralizing agents were set to ratios of 0.1, 0.67, 1.0, and 2.0 with respect to the Mn2+ mole concentration. KMnO4 exhibited a higher removal efficiency of Mn2+ than did H2O2 and NaOH, where approximately 90% of Mn2+ was removed by KMnO4. A black MnO2 was precipitated that indicated the oxidation of Mn2+ to Mn4+ after an oxidizing agent was added. In addition, MnO2 (pyrolusite) is a stable precipitate under pH-Eh conditions in the solution. However, relatively low removal ratios (6%) of Mn2+ were observed in the artificial mine drainage that included 1.0 mM of Fe2+. The rapid oxidation tendency of Fe2+ as compared to that of Mn2+ was determined to be the main reason for the low removal ratios of Mn2+. The oxidation of Fe2+ showed a decrease of Fe concentration in solution after injection of the oxidizing and neutralizing agents. In addition, Mn7+ of KMnO4 was reduced to Mn2+ by Fe2+ oxidation. Thus, the concentrations of Mn increased in artificial mine drainage. These results revealed that the oxidation method is more effective than the neutralization method for Mn removal in solution. It should also be mentioned that to achieve the Mn removal in mine drainage, Fe2+ removal must be conducted prior to Mn2+ oxidation.