• Journal of Korea Water Resources Association
• /
• v.54 no.spc1
• /
• pp.1143-1154
• /
• 2021

The selection of activation function has a great influence on the groundwater level prediction performance of artificial neural network (ANN) model. In this study, five activation functions were applied to ANN model for two groundwater level observation wells in the middle mountainous area of the Pyoseon watershed in Jeju Island. The results of the prediction of the groundwater level were compared and analyzed, and the optimal activation function was derived. In addition, the results of LSTM model, which is a widely used recurrent neural network model, were compared and analyzed with the results of the ANN models with each activation function. As a result, ELU and Leaky ReLU functions were derived as the optimal activation functions for the prediction of the groundwater level for observation well with relatively large fluctuations in groundwater level and for observation well with relatively small fluctuations, respectively. On the other hand, sigmoid function had the lowest predictive performance among the five activation functions for training period, and produced inappropriate results in peak and lowest groundwater level prediction. The ANN-ELU and ANN-Leaky ReLU models showed groundwater level prediction performance comparable to that of the LSTM model, and thus had sufficient potential for application. The methods and results of this study can be usefully used in other studies.

• The Korean Journal of Archival Studies
• /
• no.20
• /
• pp.151-212
• /
• 2009

Museums are producing new value and being redefined as places that reproduce context, as the process of globalization are being reflected in museum activities. The new additional functions and roles to the traditional mission of museums allow artworks to find potential functions of art archive and meseum. At the same time, the public has faced originality and aura of an artwork by viewing the physical subject. However, with the appearance of a new digital object, the initiative of viewing has moved over from the artwork to the hands of the public. Now, the public does not go to the museum to see an artwork, but has started to adopt to an opposite paradigm of bringing the artwork forward to the screen. Therefore, they are not satisfied any longer with just seeing an artwork, but demand more information about the artworks and reproduce it as knowledge. Therefore, this study aimed to find types and characteristics through definition and range selection of art archive at this point where the value of art archive is enhanced and systematic management is required, and to present record management methods according to art archive structure and core execution function. It especially stressed that the basis of overall art archive definition was in an 'approach' paradigm rather than a 'preservation' paradigm, and embodied various application methods of digitalized art records. The digital object of an artwork was recognized as the first materialization of an actual artwork, and the digital original of an artwork was presented as the core record. Art archive managed under physical and intellectual control were organically restructured focusing on digital original copies of artworks, which are the core record in a digital technology environment, and could be provided to users in forms of various services that meet their demands. The beginning of systematic management of such art records will become a first step to enhance historical value, establish art cultural identity, and truly possess art culture.

• Korean Journal of Heritage: History & Science
• /
• v.46 no.1
• /
• pp.208-227
• /
• 2013

Twenty-seven bronze bowls excavated from the Goryo burial complex at Deobu-gol were examined for their microstructure and chemical composition to characterize the bronze technology practiced by commoners at the time. Results showed that the objects examined can be classified into four groups: 1) objects forged out of Cu-near 22%Sn alloys and then quenched; 2) objects cast from Cu-below 10% Sn alloys containing lead; 3) objects cast from Cu-10%~20% Sn alloys containing lead and then quenched; 4) objects forged out of Cu-10~20% Sn alloys containing lead and then quenched. This study revealed that the fabrication technique as determined by alloy compositions plays an important role in bronze technology. The use of lead was clearly associated with the selection of quenching temperatures, the character of inclusions and the color characteristics of bronze surfaces. It was found that the objects containing lead were quenched at temperatures of $520^{\circ}{\sim}586^{\circ}C$ while those without lead were quenched at the range of $586^{\circ}{\sim}799^{\circ}C$. The presence of selenium in impurity inclusions was detected only in alloys containing lead, suggesting that the raw materials, Cu and Sn, used in making the lead-free alloys for the first group were carefully selected from those smelted using ores without lead contamination. Furthermore, the addition of lead was found to have significant effects on the color characteristics of the surface of bronze alloys when they are subjected to corrosion during interment. In leaded alloys, corrosion turns the surface light green or dark green while in unleaded alloys, corrosion turns the surface dark brown or black. It was found that in fabrication, the wall thickness of the bronze bowls varies depending on the application of quenching; most of the quenched objects have walls 1mm thick or below while those without quenching have walls 1mm thick or above. Fabrication techniques in bronze making usually reflect social environments of a community. It is likely that in the late Goryo period, experiencing lack of skilled bronze workers, the increased demand for bronze was met in two ways; by the use of chief lead instead of expensive tin and by the use of casting suitable for mass production. The above results show that the Goryo bronze workers tried to overcome such a resource-limited environment through technological innovations as apparent in the use of varying fabrication techniques for different alloys. Recently, numerous bronze objects are excavated and available for investigation. This study shows that with the use of proper analytical techniques they can serve as a valuable source of information required for the characterization of the associated technology as well as the social environment leading to the establishment of such technology.

• Journal of Korean Society of Coastal and Ocean Engineers
• /
• v.31 no.1
• /
• pp.28-39
• /
• 2019

In the design process of counter measures against the beach erosion, information like the main sediment transport mode and yearly net amount of longshore and cross shore transport is of great engineering value. In this rationale, we numerically analyzed the yearly sediment budget of the Mang-Bang beach which is suffering from erosion problem. For the case of cross sediment transport, Bailard's model (1981) having its roots on the Bagnold's energy model (1963) is utilized. In doing so, longshore sediment transport rate is estimated based on the assumption that longshore transport rate is determined by the available wave energy influx toward the beach. Velocity moments required for the application of Bailard's model (1981) is deduced from numerical simulation of the nonlinear shoaling process over the Mang-Bang beach of the 71 wave conditions carefully chosen from the wave records. As a wave driver, we used the consistent frequency Boussinesq Eq. by Frelich and Guza (1984). Numerical results show that contrary to the Bailard's study (1981), Irribaren NO. has non negligible influence on the velocity moments. We also proceeds to numerically simulate the yearly sediment budget of Mang-Bang beach. Numerical results show that for ${\beta}=41.6^{\circ}$, the mean orientation of Mang-Bang beach, north-westwardly moving longshore sediment is prevailing over the south-eastwardly moving sediment, the yearly amount of which is simulated to reach its maxima at $125,000m^3/m$. And the null pint where north-westwardly moving longshore sediment is balanced by the south-eastwardly moving longshore sediment is located at ${\beta}=47^{\circ}$. For the case of cross shore sediment, the sediment is gradually moving toward the shore from the April to mid October, whereas these trends are reversed by sporadically occurring energetic wind waves at the end of October and March. We also complete the littoral drift rose of the Mang-Bang beach, which shows that even though the shore line is temporarily retreated, and as a result, the orientation of Mang-Bang beach is larger than the orientation of null pont, south-eastwardly moving longshore sediment is prevailing. In a case that the orientation of Mang-Bang beach is smaller than the orientation of null pont, north-westwardly moving longshore sediment is prevailing. And these trend imply that the Mang-Bang beach is stable one, which has the self restoring capability once exposed to erosion.

• Korean Journal of Heritage: History & Science
• /
• v.54 no.2
• /
• pp.56-77
• /
• 2021

Toponyms are located not only in the site between human cognition and the physical environment but also in the name of cultural heritage. Accordingly, certain identities and ideologies for which human groups and community have sought, their holistic way of life, and all cultural symbols and cosmos, such as sense of place and genius loci, are included in their toponymic heritage. Denoting, symbolizing, integrating and representing the culture and nature belong to the human community. Based on these perceptions of the toponymic heritage, the aims of this article are to examine the values of a toponym as an Intangible Cultural Heritage (ICH) and to suggest the application methods using the toponymic functions for governing of tangible cultural heritage. This article discusses the multivocality, diversity, and non-representational theory of landscape phenomenology intrinsic to the terms of culture and cultural landscape and then the domestic and international issues on the toponymic heritage in the first chapter on the values of toponym as a part of the ICH. In particular, it analyzes the preceding research in the field of toponymy, as well as the Resolutions of UNCSGN and UNGEGN on "Geographical names as culture, heritage and identity" including indigenous, minority and regional language names since 1992, which is related to the UNESCO's Convention for the Safeguarding of the Intangible Cultural Heritage in 2003. Based on this, I suggest that the traits of toponymic cultural heritage and its five standards of selection, i.e., cultural traits of toponyms, historical traits, spatial traits, socio-economic traits and linguistic traits with some examples. In the second chapter discussing on the methods using the toponymic denoting functions for creating and governing of the tangible cultural heritage, it is underlined to maintain the systematic and unified principle regarding the ways of naming in the official cultural heritage and its governing. Lastly, I introduce the possible ways of establishing a conservative area of the historical and cultural environment while using the toponymic scale and multi-toponymic territory. Considering both the spatial and participatory turns in the field of heritage studies in addition to the multiple viewpoints and sense of cultural heritage, I suggest that the conservative area for the cultural heritage and the historical and cultural environment should be set up through choosing the certain toponymic scale and multi-toponymic territory.

• Journal of agriculture & life science
• /
• v.51 no.2
• /
• pp.117-126
• /
• 2017

Hanwoo young bulls are selected based on performance test using the weight at 12 months and pedigree index comprising marbling score. Pedigree index was not based on the progeny tested data but the breeding value of the proven bulls; resulting a lower accuracy. The progeny testing of the young bulls was categorized into testing at farm and at the test station. The farm tested data was difficult to compare with those from test station data. Farm tested bulls had different slaughter ages than those for test station bulls. Therefore, this study had considered a different age at slaughter for respective records on ultrasound traits. Records on body weight at 12 months, ultrasound measures at 12 and 24 months(uIMF, uEMA, uBFT, and uRFT), and carcass traits(CWT, EMA, BFT, and MS) were collected from steers and bulls of Hanwoo national improvement scheme between 2008 and 2013. Fixed effects of batch, test date, test station, personnel for measurement, personnel for judging, and a linear covariate of weight at measurement were fitted in the animal models for ultrasound traits. The ranges of heritability estimates of the ultrasound traits at 12 and 24 months were 0.21-0.43 and 0.32-0.47, respectively. Ultrasound traits at 12 and 24 months between similar carcass traits was genetically correlated at 0.52-0.75 and 0.86-0.89, respectively.

• Journal of agriculture & life science
• /
• v.53 no.2
• /
• pp.87-95
• /
• 2019

This study was carried out to select the rice variety for high quality rice according to reducing N application level (7 kg/10 a) in medium altitude and plain of southern Korea. It was cultivated to seven varieties and ten varieties in medium altitude and plain region respectively in this study. In medium altitude region, the yield of head rice was higher in most varieties except for Borami (526 kg/10 a) than the control variety, Chucheongbyeo (533 kg/10 a). On the other hand, Borami, Gopumbyeo, and onnuri were lower in head rice rate than the other varieties. In addition, Borami and Chucheongbyeo shown a lodging risk but the other varieties were safe against lodging. The milled rice protein content of Chucheongbyeo was 6.1% and the other varieties protein content was similar or lower than that of control except for Borami(6.3%). In plain region, the head rice yield of Nampyeongbyeo (527 kg/10 a) was higher than that of control variety, Ilmibyeo (503 kg/10 a). Head rice rate was lower in Hopumbyoe, Sindongjin, and Chilbobyeo than the other varieties. The varieties contained lower protein content compared Ilmibyeo (6.1%) were Hopumbyeo (5.9%), Jinsumi (6.0%), Sindongjin (5.9%), Chilbobyeo (6.0%), Hwangeumnodeul (5.8%), Hopyeongbyeo (6.0%). Amylose content, whiteness, and palatability (Toyo value) were no significant difference among varieties in two different regions. In conclusion, considering head rice rate, yield of head rice, protein content, lodging resistance, ripening rate and palatability, Pungmi1ho, Saenuri, Chilbobyeo in medium altitude region and Jinsumi, Hwanggumnodul in plain region were selected as proper rice varieties for high quality rice production in southern Korea.

• Korean Journal of Heritage: History & Science
• /
• v.55 no.2
• /
• pp.168-184
• /
• 2022

This paper examined the construction techniques of the earthen fortifications in the Hanseong Period of Baekje Kingdom, which has been researched most frequently among the Three Kingdoms. The construction processes of the Earthen Fortifications were reviewed and dividing into 'selection of location and construction of the base', 'construction of the wall', and 'finish, extension and repair'. The results show that various techniques were mobilized for building these earthen fortifications. Techniques which were adequate for the topography were utilized for reinforcing the base, and several other techniques were used for constructing the wall. In particular, techniques for wall construction may be clearly divided into those of the fill(盛土) and panchuk(版築) techniques. The fill method has been assumed since the 2000s to have been more efficient than the panchuk technique. This method never uses the structure of the panchuk technique and is characterized by a complex soil layer line, an alternate fill, use of 'earth mound(土堤)'/'clay clod(土塊)', and junctions of oval fill units. The fill method allows us to understand active technological sharing and application among the embankment structures in the period of the Three Kingdoms. The panchuk technique is used to construct a wall using a stamped earthen structure. This technique is divided into types B1 and B2 according to the height, scale, and extension method of the structure. Type B1 precedes B2, which was introduced in the late Hanseong Period. Staring with the Pungnap Earthen Fortification in Seoul, the panchuk technique seems to have spread throughout South Korea. The techniques of the fill and panchuk techniques coexisted at the time when they appeared, but panchuk earthen fortifications gradually dominated. Both techniques have completely different methods for the soil layers, and they have opposite orders of construction. Accordingly, it is assumed that both have different technical systems. The construction techniques of the earthen fortifications began from the Hanseong Period of Baekje Kingdom and were handed down and developed until the Woongjin-Sabi Periods. In the process, it seems that there existed active interactions with other nations. Recently, since studies of the earthen fortifications have been increasing mainly in the southern areas, it is expected that comparative analysis with neighboring countries will be done intensively.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.37 no.1
• /
• pp.104-115
• /
• 1992

The rice culture techniques included 'Jodosukyungbeob'(旱稻水耕法 : culture techniques of early-ripening paddy rice), 'Mandosukyungbeob' (晩稻水耕法) : culture techniques of late-Ripening paddy rice 'Handobeob'(旱稻＆lt;山稻＆gt;法 : culture techniques of upland rice), 'Myojongbeob'(苗種法 : culture techniques of paddy rice by transplanting), 'Kunangbeob'(乾秧法 : culture techniques of rice by transplanting which rears seeding in dry paddy) and 'Sudogunpanongbeob'(水稻乾播農法 : culture techniques of paddy rice seeding in dry field). Especially, 'Kunangbeob' and 'Sudogunpanongbeob' were originally developed in Korea as seen in 1600s(Kyoungje : 經濟) and early 1800s (Yoji : 要旨). In 'Jodosukyungbeob' it took 9 days for seed dipping, water-sprouting and prevent damage by birds, each for 3 days in China, but in Korea seed dipping in water took 3 days and the rest of the procedures were flexibly established. In matured soils, practices were fall plowing right after harvest, recognition of effective tillering and additional fertilization use of human manure, and stimulation of sprouting by lime application. The unique culture techniques adequate for Korean situations were practiced, which included weed control after draining accurately for 3 to 4 times, draining at mid season for improving wind and drought tolerance, rice harvesting at appropriate time for preventing grain shattering, and seeding in rows. 'Mandosukyungbeob' was improved techniques contrast to those of China, and the major contents were selection of proper varieties, good stand establishment by seeding high rates, induction of vigorous tillers, and adoption of 'Jokjongbeob'(足種法 : seeding method by foot). Also, one of the most prominent rice cultures by our ancestors was 'Kunpanongbeob' that was systemized form habitual practice of Pyongan Province. The unique technique actualized was 'Hando [旱稻(山稻)]' culture technique which was the combinations of 'Jokjongbeob', root stimulation method, and disaster-tolerant mixture cropping with adoptation of variety theory, although it was originated from China. The transplanting techniques has come before 'Jikseol'($\ulcorner$直說$\lrcorner$) and its merits were sufficiently realized. However, this method was basically prohibited from the early Chosun dynasty because extremely bad harvest was expected under drought conditions and insufficient conditions of water storage. But, it was permitted in the areas that contained water all the times and in case of large-scale farming especially. Most of rice culture was transplanted in the end of the Chosun dynasty because transplanting was continuously spreaded in the three southern provinces of Korea. Under these circumstances, transplanting technique was improved from the early to the end of the Chosun dynasty by weed control, fertilizing, water management, and quadratic transplanting. Based on these techniques, agricultural productivity was improved 5 times by that time. 'Kunpanongbeob' was created and developed properly for Korean conditions that is dry in early season and flooding in late season. This was successively developed and established into transplanting technique of nursery seedling.

• Korean Journal of Remote Sensing
• /
• v.39 no.6_1
• /
• pp.1413-1425
• /
• 2023

The increasing frequency of wildfires due to climate change is causing extreme loss of life and property. They cause loss of vegetation and affect ecosystem changes depending on their intensity and occurrence. Ecosystem changes, in turn, affect wildfire occurrence, causing secondary damage. Thus, accurate estimation of the areas affected by wildfires is fundamental. Satellite remote sensing is used for forest fire detection because it can rapidly acquire topographic and meteorological information about the affected area after forest fires. In addition, deep learning algorithms such as convolutional neural networks (CNN) and transformer models show high performance for more accurate monitoring of fire-burnt regions. To date, the application of deep learning models has been limited, and there is a scarcity of reports providing quantitative performance evaluations for practical field utilization. Hence, this study emphasizes a comparative analysis, exploring performance enhancements achieved through both model selection and data design. This study examined deep learning models for detecting wildfire-damaged areas using Landsat 8 satellite images in California. Also, we conducted a comprehensive comparison and analysis of the detection performance of multiple models, such as U-Net and High-Resolution Network-Object Contextual Representation (HRNet-OCR). Wildfire-related spectral indices such as normalized difference vegetation index (NDVI) and normalized burn ratio (NBR) were used as input channels for the deep learning models to reflect the degree of vegetation cover and surface moisture content. As a result, the mean intersection over union (mIoU) was 0.831 for U-Net and 0.848 for HRNet-OCR, showing high segmentation performance. The inclusion of spectral indices alongside the base wavelength bands resulted in increased metric values for all combinations, affirming that the augmentation of input data with spectral indices contributes to the refinement of pixels. This study can be applied to other satellite images to build a recovery strategy for fire-burnt areas.