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Development of Heated-Air Dryer for Agricultural Waste Using Waste Heat of Incineration Plant (소각장 폐열을 활용한 농업폐기물 열풍 건조장치 개발)

  • Song, Dae-Bin;Lim, Ki-Hyeon;Jung, Dae-Hong
    • Journal of agriculture & life science
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    • v.53 no.5
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    • pp.137-143
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    • 2019
  • To manufacturing of solid fuel by reuse of the wastes, the drying unit which have 500 kg/hr of drying capacity was developed and experimentally evaluate the performance. The spinach grown in Nam-hae island were used for the experiments and investigated of the heated-air drying characteristics as the inlet amount of raw materials, raw material stirring status, conveying type and drying time. The drying air heated by the energy derived from the steam which is supplied from the incineration plant. The moisture contents of raw materials were measured 85.65%. The inlet flow rate of drying air made a difference as the depth of the raw materials loaded on the drying unit and temperature has showed 108~144℃. The drying speed of the mixed drying more than doubled as that of non mixed drying under the same drying type, inlet amount, drying time and drying air temperature. In each experiment, the drying capacity have showed over 500 kg/hr. A drying efficiency of the ratio of drying consumption energy to input energy was 33.46%, lower than the average of 57.76% for the 157 conventional dryers. Because developed dryer must have a drying time of less than one hour, it is considered that the dry efficiency has been reduced due to the loss of wind volume during drying. If waste heat from incineration plant is used as a direct heat source, the dry air temperature is expected to be at least 160℃, greatly improving the drying capacity.

Cytotoxic Effect and Protein Expression by Korean Regional Propolis on HeLa Ovarian Cancer Cell Line (HeLa 암세포주에 대한 국산 프로폴리스의 독성 효과 및 단백질 발현 변화)

  • Kim, Sung-Kuk;Woo, Soon Ok;Han, Sang Mi;Kim, Se Gun;Bang, Kyung Won;Kim, Hyo Young;Choi, Hong Min;Moon, Hyo Jung
    • Journal of Apiculture
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    • v.34 no.3
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    • pp.245-254
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    • 2019
  • We investigated the anti-tumor effects and molecular mechanism of Brazil, China and Korean regional propolis on HeLa ovarian cancer cell line. Each propolis extracts was prepared by ethanol extraction method. Cytotoxicity of propolis extracts was determinated by EZ-cytox cell viability assay. To necessity of anti-tumor effect and molecular mechanism of propolis, we must be adjusting propolis concentration. Due to 100 ㎍/mL of propolis extract were reduced cell viability to less than 50%, we adjusted all of propolis concentration to 100 ㎍/mL. By Western blotting analysis, we confirmed that anti-tumor mechanism of Brazil, China and Korea regional propolis has significantly difference. All of propolis was activated apoptosis related molecules such as PARP, caspase-3. However, cell proliferation signaling molecules including Akt1, ERK and Bcl-2 were reduced the protein expression level. Especially, the expression of tumor suppressor protein p53 was significantly increased in propolis-treated group such as Gyeonggi, Chungbuk, Chungnam, Jeonbuk, Gyeongnam and China. The phosphorylation of Bax which as apoptosis indicator was appeared in propolis-treated group such as Gyeonggi, Gangwon, Chungnam, Gyeongbuk, China. In this results showed that the regional propolis has completely different mechanism in anti-tumor. Thus, propolis extracts may be useful source of functional materials on anti-cancer and it will be able to choose the suitable propolis for cancer therapy by analyzing individual characteristics.

Studies on the Structure and Function of the Subsidiary Baekje Temple Building Attachments - Focusing on the Buyeo Wangheungsa Temple - (백제 사찰 부속건물지의 구조와 기능 - 부여 왕흥사지를 중심으로 -)

  • Lee, Sangil
    • Korean Journal of Heritage: History & Science
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    • v.54 no.1
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    • pp.138-163
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    • 2021
  • The Buyeo Wangheungsa Temple was excavated 15 times by the Buyeo National Research Institute of Cultural Heritage by 2015. In doing this, it was confirmed that the attached buildings were placed in the east and west along with the central Sangharama building. Various building sites were established in the western section of the temple, and various buildings were placed inside, and this pattern was estimated in the eastern section. In this article, the structure and function of the attached buildings of the Wangheungsa Temple were focused on the planar structure and excavated artifacts. The most distinctive feature of the attached buildings of the Wangheungsa Temple is their construction alongside the central Sangharama building. It is different from the building to the Neungsan-ri Temple, which was expanded gradually. The attached buildings in the east and west of the lecture hall are presumed to be living space for monks who used solitary rooms, and the attached buildings in the east and west of the main hall were a combination of public work space used for things such as administration, ceremonies, and reception. Next, looking at the outer space of the central Sangharama, the western section was likely constructed at the same time as the central Sangharama. However, if you look at the building site inside the western section, the function has been changed in two stages. The first stage was a ritual space, and it is evident that the western section has a separate entrance and sidewalk and that the workshop was used as a monastery space in the second stage. Finally, there is a distinct possibility that the eastern part of the complex was an important section. Although this space is presumed to be composed of triple towers and halls, it must be have been approached in various ways and included structures related to the operation of temples, such as the monastery space. From this point on, the overall appearance of Baekje temples can be recovered through access to temple structures in a wide variety of ways, including studies of the attached buildings.

Study of Minimum Passage Size of Subterranean Termites (Reticulitermes speratus kyushuensis) (국내 흰개미(Reticulitermes speratus kyushuensis)의 최소 통과 직경 연구)

  • Kim, Sihyun;Lee, Sangbin;Lim, Ikgyun
    • Korean Journal of Heritage: History & Science
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    • v.53 no.4
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    • pp.188-197
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    • 2020
  • Termites play an important role as decomposers of the forest ecosystem, while simultaneously causing enormous damage to wooden structures. Currently, two species of subterranean termites have been reported in Korea, and termite damage to historical wooden buildings is occurring nationwide due to climate change, forest fertility, and the locational characteristics of historical wooden buildings. Subterranean termites make their nests underground or inside timber. Termites move underground and access wooden structures through the lower parts of the buildings, adjacent to the ground. Once termites attack the wooden structures, it not only spoils the authenticity of cultural heritage structure, but also hampers structural stability due to the decrease in the strength of the material. Therefore, it is important to prevent termite damage before it occurs. Chemical treatments are mainly used in Korea to control and prevent the damage. In foreign countries, physical barriers are also used to prevent entry to wooden buildings, along with chemical treatments. Physical barriers involve installing nets or particles that termites cannot pass through in the lower part of the building, around the pipes, and between the edges of the building or exterior walls and interior materials. Advantages of a physical barrier are that it is an eco-friendly method, maintains long-term effect after installation, and does not require the use of chemical treatments. Prior to applying physical barriers, studies into the characteristics of termite species must be undertaken. In this study, we evaluated the minimum passage size that each caste of Reticulitermes speratus kyushuensis can move through. We found that workers, soldiers, and secondary reproductive termites were able to pass through diameters of 0.7mm, 0.9mm, and 1.1mm respectively. Head height of termites was an important factor in determining the minimum passing size. Results from the current study will be used as a basis to design the mesh size for physical barriers to prevent damage by termites in historical wooden buildings in Korea.

The Drawing of Linked-arc Designs in Bronze Mirrors and The Technological Genealogy of the Three-Hans Style Bronze Mirror (연호문(連弧文)의 제도와 삼한경(三韓鏡)의 기술 계보)

  • Yi, Yangsu
    • Korean Journal of Heritage: History & Science
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    • v.54 no.1
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    • pp.164-183
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    • 2021
  • This article examines how the production technology of the Chinese bronze mirror affected the Korean Peninsula and Japan. To that end, we looked at how the drawing of linked-arc designs in bronze mirrors was done. The drawing technique is classified into three methods: Type 1 and type 2 were confirmed to have been used in China, but type 3 was used not in China, but on the Korean Peninsula and in Japan. Type 1 and type 2 are basically the same, with an identical restored diameter of the linked-arc design, and type 2 is found elsewhere in the bronze mirror, and type 1 are not. Type 3 features different diameters, and the linked-arc design does not form a complete circle. This shows that the manufacturer of the bronze mirror did not use several bumpy compasses, but rather a single one with a fixed center and protrusion, rather than one that can be easily adjusted, as it is today. That is why, of course, a pair of compasses must have been used several times. In this regard, those who produced bronze mirrors on the Korean Peninsula in the early days understood not only the Chinese techniques of the linked-arc design, but also the meaning contained within them. On the other hand, the makers of bronze mirrors in Japan did not understand the patterns and simply imitated them. From the late Yayoi period, Japan understood and produced works with the principle of drawing the linked-arc design. As a representative example, bronze mirrors excavated from the tomb of Hirabaru can be referenced. Perhaps it can be assumed that, behind these works, there was a direct transfer of technology, such as the migration of the makers of bronze mirror makers like the Do family (陶氏), whose names were found written on bronze mirrors excavated from the Hirabaru tomb.

A Study on Cu-based Catalysts for Oxygen Removal in Nitrogen Purification System (질소 정제 시스템의 산소 제거용 구리계 촉매 연구)

  • Oh, Seung Kyo;Seong, Minjun;Jeon, Jong-Ki
    • Clean Technology
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    • v.27 no.1
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    • pp.9-16
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    • 2021
  • Since the active matrix organic light-emitting diode (AMOLED) encapsulation process is very vulnerable to moisture and oxygen, high-purity nitrogen with minimal moisture and oxygen must be used. In this study, a copper-based catalyst used to remove oxygen from nitrogen in the AMOLED encapsulation process was optimized. Two-component and three-component catalysts composed of CuO, Al2O3, or ZnO were prepared through a co-precipitation method. The prepared catalysts were characterized by using BET, XRD, TPR, and XRF analysis. In order to verify the oxygen removal performance of the catalyst, several catalytic reactions were conducted in a fixed bed reactor, and the corresponding oxygen contents were measured through an oxygen analyzer. In addition, reusability of the catalysts was proven through repetitive regeneration. The properties and oxygen removal capacity of the catalysts prepared with CuO and Al2O3 ratios of 6 : 4, 7 : 3, and 8 : 2 were compared. The number of active sites of the catalyst with a ratio of CuO and Al2O3 of 8 : 2 was the highest among the 2-component catalysts. Moreover, the reducibility of the catalyst with a ratio of CuO and Al2O3 of 8 : 2 was the best as it had the highest CuO dispersion. As a result, the oxygen removal ability of the catalyst with a ratio of CuO and Al2O3 of 8 : 2 was the best among the 2-component catalysts. The best oxygen removal capacity was obtained when 2wt% of ZnO was added to the sub-optimized catalyst (i.e., CuO : Al2O3 = 8 : 2) probably due to its outstanding reducibility. Furthermore, the optimized catalyst kept its performance during a couple of regeneration tests.

Reconstruction of the Origin of the Gudle (구들의 기원지(起源地) 재고(再考))

  • Oh, Seunghwan
    • Korean Journal of Heritage: History & Science
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    • v.54 no.1
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    • pp.100-119
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    • 2021
  • This paper has been written to verify the existing theory that districts occurred independently in various parts of the world, including the Korean Peninsula. Song Giho (2006) claims that the origin of the Gudle, is an example of polygenism that occurred in various areas in the world, including the Korean peninsula. This argument has been corroborated by a large number of researchers. However, it is difficult to understand the lineage of Gudle and its process of development, if a theory of polygenism is continued to be taken into account. The place which is targetet by this theory is the North-West area of the Korean peninsula, south of Primorsky Krai, and in the northern area of Zabaikal-Mongolia. This means that these areas developed independently because they were far from each other and had no direct cultural relationship. However, the structure of Gudle, shape, and assemblages of earthenware it cannot be explained by polygenism, as they are the same in every place. Furthermore, it is also questionable as to the timing and region of emergence of the culture in East Asia over a limited time frame of 3-2 BC. Gudle are formed by furnaces with roofs and walls, Gorae, which saves heat, and it has smoke ventilation that draws smoke out. Therefore, the Gudle is not a structure that anyone can make without advanced technical understanding. So far, the only facility with furnaces and smoke ventilation that appear before the Gudle is Buttumak. Thus, the Gudle is likely to have been invented in the place where Buttumak were used. The area as known for the origin of Gudle was observed to verify the existence of the Buttumak's structure, but none of these facilities were found. The Gudle suddenly appeared within a new culture that had never existed before. That means that none of the three places had the conditions under which the Gudle could be invented, so it must have been introduced from outside. In conclusion, the three places that I mentioned above are not the origin of Gudle. So, the origin of Gudle has to be found elsewhere.

Diagnostic Evaluation of the BioFire® Meningitis/Encephalitis Panel: A Pilot Study Including Febrile Infants Younger than 90 Days (BioFire® Meningitis/Encephalitis Panel의 진단적 유용성 평가: 90일 미만 발열영아에서의 예비 연구)

  • Kim, Kyung Min;Park, Ji Young;Park, Kyoung Un;Sohn, Young Joo;Choi, Youn Young;Han, Mi Seon;Choi, Eun Hwa
    • Pediatric Infection and Vaccine
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    • v.28 no.2
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    • pp.92-100
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    • 2021
  • Purpose: Rapid detection of etiologic organisms is crucial for initiating appropriate therapy in patients with central nervous system (CNS) infection. This study aimed to evaluate the diagnostic value of the BioFire® Meningitis/Encephalitis (ME) panel in detecting etiologic organisms in cerebrospinal fluid (CSF) samples from febrile infants. Methods: CSF samples from infants aged <90 days who were evaluated for fever were collected between January 2016 and July 2019 at the Seoul National University Children's Hospital. We performed BioFire® ME panel testing of CSF samples that had been used for CSF analysis and conventional tests (bacterial culture, Xpert® enterovirus assay, and herpes simplex virus-1 and -2 polymerase chain reaction) and stored at -70℃ until further use. Results: In total, 72 (24 pathogen-identified and 48 pathogen-unidentified) CSF samples were included. Using BioFire® ME panel testing, 41 (85.4%) of the 48 pathogen-unidentified CSF samples yielded negative results and 22 (91.7%) of the 24 pathogen-identified CSF samples yielded the same results (enterovirus in 19, Streptococcus agalactiae in 2, and Streptococcus pneumoniae in 1) as those obtained using the conventional tests, thereby resulting in an overall agreement of 87.5% (63/72). Six of the 7 pathogen-unidentified samples were positive for human parechovirus (HPeV) via BioFire® ME panel testing. Conclusions: Compared with the currently available etiologic tests for CNS infection, BioFire® ME panel testing demonstrated a high agreement score for pathogen-identified samples and enabled HPeV detection in young infants. The clinical utility and cost-effectiveness of BioFire® ME panel testing in children must be evaluated for its wider application.

Research of the Moderating Effect on Team Members' Self-leadership of the Executive Officer's Emotional Leadership: Focus on the Differences between MZ Generation and the Others (경영자 감성리더십이 팀원의 셀프리더십에 미치는 조절효과에 대한 연구: MZ 세대와의 차이를 중심으로)

  • Cho, Chanhi;Lee, Hyoung-Yong
    • Knowledge Management Research
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    • v.22 no.4
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    • pp.261-282
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    • 2021
  • As the MZ generation, who values work-life balance, became a member of the organization, leader-oriented leadership centered on goal achievement and company profit made it difficult to achieve good results in the organization in the mid-to long-term. The company must strengthen the leadership that can be helpful for the self-leadership where the members of the organization move on their own and the organizational culture that enhances the employees' job satisfaction and organizational commitment. Therefore, this study analyzed the effect of the team leader's servant leadership on the team member's self-leadership and organizational effectiveness. In addition, it was studied whether the executive officer's emotional leadership interacted with the team leader's servant leadership and had a moderating effect on the team member's self-leadership. Also, the difference in path coefficient between the MZ generation and the non-MZ generation was verified. To this end, the research model was statistically verified using the PLS (Partial Least Square) structural equation. A survey was collected from 357 team members among office workers online. As a result of the analysis, the team leader's servant leadership had a significant effect on organizational effectiveness and team member's self-leadership. Also, in the relationship between the team leader's servant leadership and the team member's self-leadership, the emotional leadership of the executive officer had a positive (+) moderating effect. The MZ generation differed from the non-MZ generation in the path where the team leader's servant leadership positively affected the self-leadership of the team member and the path where the team leader's self-leadership had a mediating effect between the team leader's servant leadership and organizational effectiveness. The results of this study will suggest various theoretical and practical implications so that executive officers, team leaders, and team members within the company can develop leadership that increases organizational effectiveness in their respective positions.

An Outlier Detection Using Autoencoder for Ocean Observation Data (해양 이상 자료 탐지를 위한 오토인코더 활용 기법 최적화 연구)

  • Kim, Hyeon-Jae;Kim, Dong-Hoon;Lim, Chaewook;Shin, Yongtak;Lee, Sang-Chul;Choi, Youngjin;Woo, Seung-Buhm
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.33 no.6
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    • pp.265-274
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    • 2021
  • Outlier detection research in ocean data has traditionally been performed using statistical and distance-based machine learning algorithms. Recently, AI-based methods have received a lot of attention and so-called supervised learning methods that require classification information for data are mainly used. This supervised learning method requires a lot of time and costs because classification information (label) must be manually designated for all data required for learning. In this study, an autoencoder based on unsupervised learning was applied as an outlier detection to overcome this problem. For the experiment, two experiments were designed: one is univariate learning, in which only SST data was used among the observation data of Deokjeok Island and the other is multivariate learning, in which SST, air temperature, wind direction, wind speed, air pressure, and humidity were used. Period of data is 25 years from 1996 to 2020, and a pre-processing considering the characteristics of ocean data was applied to the data. An outlier detection of actual SST data was tried with a learned univariate and multivariate autoencoder. We tried to detect outliers in real SST data using trained univariate and multivariate autoencoders. To compare model performance, various outlier detection methods were applied to synthetic data with artificially inserted errors. As a result of quantitatively evaluating the performance of these methods, the multivariate/univariate accuracy was about 96%/91%, respectively, indicating that the multivariate autoencoder had better outlier detection performance. Outlier detection using an unsupervised learning-based autoencoder is expected to be used in various ways in that it can reduce subjective classification errors and cost and time required for data labeling.