• Korean Journal of Heritage: History & Science
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• v.34
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• pp.60-79
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• 2001

We can infer from collections of prose in Cho-sun period that the main period is from King Se-jong's reign to King Yoeng-jo's or between the 15th and the 17th century. The ideological background and the dignity of the rock garden is derived from Taoist hermitism and Nitze and Jeng-je's quietism. The representation of the rock garden as tri-god mountain comprising Bong-lai, Bang-jang and Young-ju is based on the tradition of making the tripartite rock garden in a pond practiced in the three north-eastern countries, Korea, China and Japan. And it's the representation of quietistic world of eternal life that had been sought by the taoism. Making a pond in which they plant lotus and made rock garden. they enjoyed watching immaculately pure lotus flower bloom even in the mud. It is compared to the confucians' seeking for virtue even in the profane or defiled world. Another motive of intellectuals to make rock gardens is their love of nature and its landscapes and their preference of recluse and temperate life to attaching to high public office, which was the tendency of the learned, established by the influence of taoist and quietist tradition. The essays portray the fountain water, ponds, waterfalls. the hilltops, the mountain pass over the ridge. winded lanes, valleys, caverns, and other architectural elements. The technic of building rock gardens includes those of harmonizing each elements of landscapes in the water, that of irrigation, building formation, and those of piling up the mountains and hills. With some comments on planting trees, grass and flowers. The original location of rock garden, esp. in case of taoist Chae-su's rock garden with waterfalls, is Ian-ri, Ian-myon in the city Sang-ju. Since no relics of rock gardens are to be found in any examples of Korea's traditional gardening, the study of rock gardening by analyzing the prose collections of Cho-sun period can be significant for the study of designing water space that has been considered the center of a garden space.

• Tribology and Lubricants
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• v.37 no.3
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• pp.99-105
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• 2021

In this study, for a high-pressure turbine (HPT) of 800 MW class supercritical thermal-power plant, considering aerodynamic cross-coupling, we performed a rotordynamic logarithmic decrement (LogDec) stability analysis with various tilting pad journal bearing (TPJB) designs, which several steam turbine OEMs (original equipment manufacturers) currently apply in their supercritical and ultra-supercritical HPTs. We considered the following TPJB designs: 6-Pad load on pad (LOP)/load between pad (LBP), 5-Pad LOP/LBP, Hybrid 3-Pad LOP (lower 3-Pad tilting and upper 1-Pad fixed), and 5-Pad LBPs with the design variables of offset and preload. We used the API Level-I method for a LogDec stability analysis. Following results are summarized only in a standpoint of LogDec stability. The Hybrid 3-Pad LOP TPJBs most excellently outperform all the other TPJBs over nearly a full range of cross-coupled stiffness. In a high range of cross-coupled stiffness, both the 6-Pad LOP and 5-Pad LOP TPJBs may be recommended as a practical conservative bearing design approach for enhancing a rotordynamic stability of the HPT. As expected, in a high range of cross-coupled stiffness, the 6-Pad LBP TPJBs exhibit a better performance than the 5-Pad LBP TPJBs. However, contrary to one's expectation, notably, the 5-Pad LOP TPJBs exhibit a slightly better performance than the 6-Pad LOP TPJBs. Furthermore, we do not recommend any TPJB design efforts of either increasing a pad offset from 0.5 or a pad preload from 0 for the HPT in a standpoint of stability.

• Journal of The Korean Society of Agricultural Engineers
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• v.64 no.1
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• pp.79-89
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• 2022

Soil moisture is significantly related to crop growth and plays an important role in irrigation management. To predict soil moisture, various process-based model has been developed and used in the world. Various models (Land surface model) may have different performance depending on the model parameters and structures that causes the different model output for the same modeling condition. In this study, the three land surface models (Noah Land Surface Model, Soil Water Atmosphere Plant, Community Land Model) were used to compare the model performance (soil moisture prediction) and develop the multi-model simulation. At first, the genetic algorithm was used to estimate the optimal soil parameters for each model, and the parameters were used to predict soil moisture in the study area. Then, we used the multi-model approach based on Bayesian model averaging (BMA). The results derived from this approach showed a better match to the measurements than the results from the original single land surface model. In addition, identifying the strengths and weaknesses of the single model and utilizing multi-model methods can help to increase the accuracy of soil moisture prediction.

• International Journal of Industrial Entomology and Biomaterials
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• v.43 no.2
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• pp.67-77
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• 2021

Salurnis marginella Guérin-Méneville, 1829 (Hemiptera: Flatidae) is an invasive species first reported in 2003 in Iksan, which is located in the mid-western region of South Korea, and subsequently found in the nearby regions in 2005. However, molecular-perspective reports on their invasive characteristics are not yet available. In this study, population genetic characteristics of Korean S. marginella were evaluated using the mitochondrial COI region and sequencing 124 individual samples collected in 11 Korean localities. A total of 12 haplotypes were identified with a maximum sequence divergence of 1.368% (9 bp). Haplotype diversity was relatively higher than that of other insect species invaded into Korea, providing 2-6 haplotypes per populations, indicating that introduction to Korea may have happened rather extensively and consistently. Nucleotide diversity (π) was the highest in Iksan but owing to the limited sample size (three individuals) from this locality, additional studies are required for drawing conclusive inference regarding the place of entry to Korea. Ulsan, the easternmost population in the present study, revealed nearly the lowest diversity estimates, such as the lowest H and the second-lowest π; a unique haplogroup with a higher frequency; and an independent genetic cluster, suggesting that the introduction of S. marginella to Ulsan was an independent event. Further collection in Korea and neighboring countries, including the original distributional range is necessary to elucidate the invasive dynamics of S. marginella

• Nuclear Engineering and Technology
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• v.53 no.3
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• pp.763-775
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• 2021

The thermal hydraulic performances of Steam Generator (SG) under both steady and transient operation conditions are of great importance for the safety and economy in nuclear power plants. In this paper, based on our self-developed SG thermal hydraulic analysis code STAF (Steam-generator Thermalhydraulic Analysis code based on Fluent), an improved new version STAF-CT (fully Coupling and Transient) is developed and introduced. Compared with original STAF, the new version code STAF-CT has two main functional improvements including "Transient" and "Fully Three Dimensional Coupling" features. In STAF-CT, a three dimensional energy transferring module is established which can achieve energy exchange computing function at the corresponding position between two sides of SG. The STAF-CT is validated against the international benchmark experiment data and the results show great agreement. Then the U-shaped SG in AP1000 nuclear power plant is modeled and simulated using STAF-CT. The results show that three dimensional flow fields in the primary side make significant effect on the energy source distribution between two sides. The development of code STAF-CT in this paper can provide an effective method for further SG high fidelity research in the nuclear reactor system.

• The Korea Journal of Herbology
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• v.28 no.5
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• pp.13-19
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• 2013

Objectives : The purpose of this study is correct the scientific name of Aquilariae Lignum in Korean Herbal Pharmacoepia. Methods : The production areas of Aquilariae Lignum and its trading status with China in Chinese history, Sanscrit-Chinese Translation Sutra, Naming year and the discovered district in main Aquilaria spp., Several nation's Pharmacoepia, The Plant List(TPL), Convention on International Trade in Endangered Species of Wild fauna and flora(CITES) and The International Union for Conservation of Nature(IUCN) were cross-checked. Results : The records in the Jiaozhouyiwuzhi written in the early 2nd century said that Aquilariae Lignum was produced in Vietnam. NanfangCaomuZhuang written in 304 said that Agarwood in Vietnam had white flowers. Vietnam had led production and trading of Aquilariae Lignum until Qing Dynasty. Aquilariae Lignum from Malaysia and Indonesia was not traded with China. In Sanscrit-Chinese Translation Sutra, India Aquilariae Lignum was translated as Vietnam Aquilariae Lignum. Aquilaria malaccensis was discovered from Malay-Peninsular in 1783, and has green or dirty yellow flowers. A. agallocha from North-Eastern India in 1814, white flowers. A. crasssna from Vietnam in 1914, white flowers. A. crassna is different from A. malaccensis in several ways, such as flower, fruit, seed and disribution. In several Nation's Pharmacoepia, A. crassna was a synonym of A. agallocha. But in TPL, CITES and IUCN, A. malaccensis was an accepted name, and A. agallocha was a synonym of A. malaccensis. Conclusions : These results show that the original species of Aquilariae Lignum in Korea Herbal Pharmacoepia should be reversed from A. agallocha to A. crassna Pierre ex Lacomte.

• The Korea Journal of Herbology
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• v.28 no.5
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• pp.1-6
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• 2013

Objectives : This study was conducted to identify the original Sinomini Caulis et Rhizoma plant among Stephania tetrandra, Cocculus trilobus, and Aristolochiae fangchi to develop the genetic marker for Sinomini Caulis et Rhizoma. Methods : Sinomenium acutum was identified by the classification and identification committee of the National Center for Standardization of Herbal Medicines. The chloroplast ndhF gene was amplified. We performed sequences alignment analysis of Sinomenium acutum, Stephania tetrandra, C. trilobus, and A. fangchi using BioEdit program. The SFR markers designed were consisted of SF01, SR04, and SR05 primers. Results : Many variations of Sinomeni Caulis et Rhizoma are currently commercialized as herbal medicine. We compared the base sequences of the ndhF intergenic space of chloroplast DNA with Sinomenium acutum, Stephania tetrandra, C. trilobus, and A. fangchi. According to the results, it showed that the nucleotide variations were seen in 30 genes of four species. Phylogenetic analysis revealed that 4 species were classified into five groups based on an inter-group divergence in nucleotide sequence of 9%. We developed SFR marker nucleotides enough to authenticate respective species and confirmed its application on the band size at 419 base pair. These sequence differences at corresponding positions were available genetic markers to identity the Sinomeni Caulis et Rhizoma. Conclusions : Base on these results, the ndhF region was effective in distinguishing Sinomini Caulis et Rhizoma The SFR genetic marker was useful for identifying Sinomini Caulis et Rhizoma with other species.

• The Korea Journal of Herbology
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• v.35 no.2
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• pp.15-29
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• 2020

Objectives : This study aimed to review the change in the origin of Sokdan(續斷) by diachronically analyzing literature data from Korea and China. Methods : Literature records describing the origin(synonyms, location of production, description) of Sokdan were collected, records were divided into periods. The main contents were included in the results, and original texts were edited and summarized in the table. Results : Sokdan, whose leaves resemble Jeoma(苧麻)(SJ), was first recorded in 《Xinxiubencao(新修本草)》, and described in detail in 《Bencaotujing(本草圖經)》 during the Tang and Song dynasties in China. In modern times, SJ was assumed to be genus Phlomoides or Lamium; however, records of the plant have decreased. Finally, SJ was not included in the 《Pharmacopoeia of the People's Republic of China》 as Sokdan. However, 《Diannanbencao(滇南本草)》, 《Diannanbencaotushuo(滇南本草圖說)》, 《Zhiwumingshitukao(植物名實圖考)》 described Sokdan of dian(滇). It was assumed genus Dipsacus. From the 1950s onwards, Sokdan is described in the literature as a member of the genus Dipsacus. In korea, SJ was recorded in 《Hyangyakjipseongbang(鄕藥集成方)》 and 《Dongeuibogam(東醫寶鑑)》 during the Joseon dynasty. In modern times, the genera Phlomoides and Lamium were mostly recorded as the origin of Sokdan. Conclusions : Several species have been described as Sokdan over the years in China, but since the 1950s, the genus Dipsacus was noted as the origin of Sokdan. In Korea, SJ was used in the past, thus Sokdan was recorded as P. umbrosa in 《The Korean Herbal Pharmacopoeia(KHP)·1985》. However, 《KHP·1998》 referred to P. umbrosa as Hansokdan and D. asperoides as Sokdan.

• The Korea Journal of Herbology
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• v.24 no.2
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• pp.67-76
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• 2009

Objectives : The present study compared Aralia continentalis Root and Angelica pubescens Root used in Korea and China respectively concerning their anti-oxidant effect Methods : We tested the anti-oxidant effect through in vitro experiment and in vivo experiment that induced oxidative stress using ethanol. Results : 1. DPPH scavenging activity was stronger in Aralia continentalis Root than in Angelica pubescens Root 2. Superoxide anion radical scavenging activity was similar between Aralia continentalis Root and Angelica pubescens Root 3. The linoleic acid peroxidation inhibition effect was stronger in Aralia continentalis Root than in Angelica pubescens Root. 4. The phenolic component was higher in Aralia continentalis Root than in Angelica pubescens Root. 5. Both Aralia continentalis Root and Angelica pubescens Root increased the concentration of GSH and decreased SOD activity in mice, in which oxidative stress was induced, and the effect was stronger in Aralia continentalis Root. 6. Aralia continentalis Root increased GSH peroxidase activity but Angelica pubescens Root did not have such an effect. 7. Neither Aralia continentalis Root nor Angelica pubescens Root had a significant effect on catalase, ADH and ALDH in mice, in which oxidative stress was induced. Conclusions : Aralia continentalis Root has a stronger anti-oxidant effect than Angelica pubescens Root. Thus, although Aralia continentalis Root is not an original plant recorded in botanical literature, it may be usable based on the data about its effects.

• Nuclear Engineering and Technology
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• v.55 no.6
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• pp.2096-2106
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• 2023

Rotating machinery is widely applied in important equipment of nuclear power plants (NPPs), such as pumps and valves. The research on intelligent fault diagnosis of rotating machinery is crucial to ensure the safe operation of related equipment in NPPs. However, in practical applications, data-driven fault diagnosis faces the problem of small and imbalanced samples, resulting in low model training efficiency and poor generalization performance. Therefore, a deep convolutional conditional generative adversarial network (DCCGAN) is constructed to mitigate the impact of imbalanced samples on fault diagnosis. First, a conditional generative adversarial model is designed based on convolutional neural networks to effectively augment imbalanced samples. The original sample features can be effectively extracted by the model based on conditional generative adversarial strategy and appropriate number of filters. In addition, high-quality generated samples are ensured through the visualization of model training process and samples features. Then, a deep convolutional neural network (DCNN) is designed to extract features of mixed samples and implement intelligent fault diagnosis. Finally, based on multi-fault experimental data of motor and bearing, the performance of DCCGAN model for data augmentation and intelligent fault diagnosis is verified. The proposed method effectively alleviates the problem of imbalanced samples, and shows its application value in intelligent fault diagnosis of actual NPPs.