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As the need for teaching Artificial Intelligence (AI) for K-12 is increasing, discussions on what competencies teacher should have for effective teaching of AI is overlooked. In this work, we determine what teacher competencies are necessary for improving the teaching and learning of AI for K-12 with Technological Pedagogical Content Knowledge (TPACK) framework. First, we identify current AI education resources and investigate the core foundations of AI taught to K-12. Based on the findings, we propose teacher competency for K-12 AI education by analyzing AI curricula and resources using the TPACK framework. We conclude that teachers who teach AI to K-12 students require TPACK to construct, prepare an environment, and facilitate project-based classes that solve problems using AI technologies.

Colorectal cancer (CRC) is the third leading cause of cancer-related deaths in the US. Understanding the mechanisms of CRC progression is essential to improve treatment. Mitochondria is the powerhouse for healthy cells. However, in tumor cells, less energy is produced by the mitochondria and metabolic reprogramming is an early hallmark of cancer. The metabolic differences between normal and cancer cells are being interrogated to uncover new therapeutic approaches. Mitochondria targeting PTEN-induced kinase 1 (PINK1) is a key regulator of mitophagy, the selective elimination of damaged mitochondria by autophagy. Defective mitophagy is increasingly associated with various diseases including CRC. However, a significant gap exists in our understanding of how PINK1-dependent mitophagy participates in the metabolic regulation of CRC. By mining Oncomine, we found that PINK1 expression was downregulated in human CRC tissues compared to normal colons. Moreover, disruption of PINK1 increased colon tumorigenesis in two colitis-associated CRC mouse models, suggesting that PINK1 functions as a tumor suppressor in CRC. PINK1 overexpression in murine colon tumor cells promoted mitophagy, decreased glycolysis and increased mitochondrial respiration potentially via activation of p53 signaling pathways. In contrast, PINK1 deletion decreased apoptosis, increased glycolysis, and reduced mitochondrial respiration and p53 signaling. Interestingly, PINK1 overexpression in vivo increased apoptotic cell death and suppressed colon tumor xenograft growth. Metabolomic analysis revealed that acetyl-CoA was significantly reduced in tumors with PINK1 overexpression, which was partly due to activation of the HIF-1α-pyruvate dehydrogenase (PDH) kinase 1 (PDHK1)-PDHE1α axis. Strikingly, treating mice with acetate increased acetyl-CoA levels and rescued PINK1-suppressed tumor growth. Importantly, PINK1 disruption simultaneously increased xenografted tumor growth and acetyl-CoA production. In conclusion, mitophagy protein PINK1 suppresses colon tumor growth by metabolic reprogramming and reducing acetyl-CoA production.

We examined the microfabrics of omphacite and garnet in foliated eclogite to determine the influence of the layered structure on seismic observations in subduction zone. The analyzed eclogite, from the Lanterman Range, northern Victoria Land, Antarctica, is characterized by layering in which the modal abundances of garnet and omphacite vary. For garnet, the low aspect ratios, similar angular distribution of long axes relative to the foliation in both layers, uniform grain size distribution, near-random crystallographic preferred orientations (CPOs), and misorientation angle distributions are indicative of passive behavior during deformation. In contrast, omphacite shows relatively high aspect ratios, a low angle between the long axes of crystals and the foliation, a wide grain-size distribution, and distinctive CPOs, suggesting dislocation creep as the main deformation mechanism. The results of fabric analyses are consistent with strain localization into omphacite or omphacite-rich layers rather than garnet or garnet- rich layers. The single-crystal seismic anisotropy of garnet is very weak (AVP = 0.2%, AVS = 0.5–0.6%), whereas that of omphacite is much stronger (AVP = 3.7–5.9% and AVS = 2.9–3.8%). Seismic anisotropy of the omphacite-rich layers shows an increase of 329% for AVP and 146% for AVS relative to the garnet-rich layers. Our results demonstrate the importance of the layered structure in strain localization and in the development of the seismic anisotropies of subducting oceanic crust.

With the evolution of information technology, devices such as smart TVs allow users to easily search for broadcast information, browse, participate in broadcasting, shop, etc. However, while watching, such additional information can be obstructive elements when seen by other people. Moreover, such smart functionalities cannot be utilized in public places. Therefore, in order to address the problem of the viewing disturbance element and formulate a method of providing the information, it is necessary to photograph the TV or the monitor screen using a smart device and immediately transmit the requisite information such as P2P information and advertisement information. We designed and implemented a system that allows confirmation. The proposed system minimizes interruption of viewing and presents a new user experience model so that anyone can easily use screenshots to generate additional information. A region of interest is extracted from a frame of a moving image photographed for efficiently searching for additional information such as the position information of the region of interest, the size information, and the projection information of the image edge of the region of interest. As a result of the experiment, it was confirmed that the additional information matched the video image shot using the smart device.

The goal of this study is to explore the perceptions of teachers in Korean rural schools regarding teaching and learning, including technology preparedness, performance, demanding activities, difficulties, and continuing integration in tablet-based interactive classrooms. A survey instrument was designed, and responses were analyzed from 54 teachers who participated in a social contribution project for rural schools. The results indicate that student preparedness is significantly correlated with the frequent integration of tablets in classroom lessons. Furthermore, the most frequent types of pedagogical activities performed using tablets in the classroom are activities intended to motivate students. Teachers noted that their continuing integration of lessons with tablets was correlated with their beliefs about the applicability of tablets for lessons, students’ satisfaction with previous lessons, students’ expectations and requests, and the teacher’s personal interests. This research contributes to the literature on tablet integration by extending existing findings to the study of rural schools with limited educational resources. Moreover, this study provides implications for educators and school administrators who are interested in supporting teachers and their instruction using tablets and relevant technologies.

This study proposes a system that can recognize human emotional state from bio-signal. The technology is provided to improve the interaction between humans and computers to achieve an effective human–machine that is capable for intelligent interaction. The proposed method is able to recognize six emotional states, such as joy, happiness, fear, anger, despair, and sadness. These set of emotional states are widely used for emotion recognition purposes. The result shows that the proposed method can distinguish one emotion compared to all other possible emotional states. The method is composed of two steps: 1) multi-modal bio-signal evaluation and 2) emotion recognition using artificial neural network. In the first step, we present a method to analyze and fix human sensitivity using physiological signals, such as electroencephalogram, electrocardiogram, photoplethysmogram, respiration, and galvanic skin response. The experimental analysis shows that the proposed method has good accuracy performance and could be applied on many human–computer interaction devices for emotion detection.

Sentiment analysis requires a sentiment dictionary that maps words to sentiments. Further, sentiment weight is an important subtopic in the measurement of the strength of sentiments. A sentiment is the emotional response of an individual toward an external stimulus; therefore, the sentiment valence and sentiment weight vary among different persons. Hence, the definition and expression of a sentiment as a single state is a challenging task. In this study, we address the challenges in building a sentiment dictionary and analyzing sentiment weight. We construct a sentiment dictionary and propose a method to analyze word sentiments. We use the proposed method to analyze the general sentiments in social media. In our experiments, we used Flickr as the social media application and collected user responses to a sample post in order to utilize collective intelligence. We made four observations about this approach: (1) approximately 30 % of the words used in communication on social media signify a sentiment; (2) in addition to verbs and adjectives, nouns can be used for sentiment analysis; (3) 98.25 % of the seed words and words classified for sentiments matched; (4) the sentiment weight distribution was more concentrated for SO-NPMI than for SO-PMI.

This paper presents a real-time watermarking codec that is robust against re-encoding attacks for high-definition videos. The codec uses a segmentation function and texture detector techniques for applying real-time watermarking to human visual systems. Experimental results confirm that the proposed scheme satisfies the requirements of invisibility, real-time processing, and robustness against format conversion and low bit-rate encoding. The proposed algorithm has the advantages of simplicity, flexibility, and low computational burden; thus, it is a suitable candidate for many novel and interesting applications such as video fingerprinting for set-top boxes, Internet protocol television, personal video recorders, and satellite boxes.

Information and communication technology (ICT) literacy education has become an important issue, and the necessity of computational literacy (CL) has been increasing in our growing information society. CL is becoming an important element for future talents, and many countries, including the USA, are developing programs for CL education. Accordingly, Korea’s Ministry of Education has modified the ICT education program created in 2000. The revised curriculum has emphasized computational thinking and informational ethics since 2007. However, in revising the ICT curriculum, we need to develop a new ICT test tool because the previous tool did not include CL. Thus, we developed a new ICT literacy test tool consisting of fundamental concepts, contemporary skills, and CL. We then carried out a test on 40,072 elementary students nationally. To determine the CL level of students, we used the standard level obtained from ten experts using the Angoff method (1971) and analyzed the difference between the standard level and students’ level in the test. The results showed that students’ CL scores were remarkably lower than their scores on fundamental concepts and contemporary skills. We consequently found that the revised ICT curriculum did not apply to the current ICT education domain, implying that we need to develop a strategy to expand CL to different educational fields, which would help researchers and administrators to measure CL in ICT education.

Zircon U-Pb geochronology was applied to a migmatitic gneiss in the Busan gneiss complex, Gyeonggi massif, Korea. 207Pb/206Pb ages of concordant zircon grains reveal that overgrowth rims with Th/U ratios lower than 0.1 formed at 1937 ± 6 Ma during the migmatization and mantled the inherited cores of ca. 3500–2200 Ma. The 207Pb/206Pb age of the rims is consistent with the monazite Th-total Pb age (ca. 1938 Ma), suggesting that the rims are the product of Paleoproterozoic regional metamorphism. Our zircon age data are not sufficient for discerning the tectonic affinity of the Busan gneiss complex belonging to either Gyeonggi or Yeongnam massif. However, consistency of these ages with the ca. 1930 Ma Pb-Pb age reported from the Bagdalryeong gneiss complex, Gyeonggi massif, supports the tectonic model that the Busan gneiss complex is a part of the Gyeonggi massif. Discordant U-Pb data obtained from the zircon rims (293 ± 31 Ma) and the monazite Th-total Pb age (ca. 289 Ma) suggest that the Busan gneiss complex was affected by the Early Permian regional metamorphism during the Ogcheon (Okcheon) Orogeny. Therefore, we conclude that the Busan gneiss complex is a part of the Gyeonggi massif occurring as either a basement rock of the Ogcheon (Okcheon) metamorphic rocks, or a tectonically emplaced, exotic piece affected by the Early Permian Ogcheon (Okcheon) metamorphism. In addition, our U-Pb data suggest that the Busan complex is possibly linked with the Hida-Oki terrane in Japanese Islands.

This study focuses on the depositional and deformational features of quartzite-shale and phyllite beds in the lower part of the Seochangri Formation, Okcheon Group, mid-Korea. Each quartzite unit (25–320 cm thick) is massive, whereas the overlying laminated shale unit (0.5–10 cm thick) is either homogeneous or slightly laminated. Although these interbeds were strongly deformed under brittle-ductile conditions (ca. 300°C), the quartzite units show a thickening-upward trend. The quartzite-shale interbeds represent deposition from turbidity currents, i.e., Bouma-A and-D/E divisions. The thickening-upward quartzite-shale units are suggestive of progradation of sand lobes in the middle-outer fan. The overlying phyllite beds with thin quartz interlayers most likely represent outer fan and basinplain environments. The Seochangri Formation in the Bonghwajae section forms a thrust front against the limestone and dolomite beds of the Joseon Supergroup in which the quartzite-shale units are overlain by the phyllite beds and, in turn, underlain by the folded limestone beds. The phyllite and limestone beds were strongly deformed, showing upright isoclinal to tight folds, sheath folds, and boudins. The fold axes generally trend north-northeast with a low plunge angle. The thrust front represents part of the restraining bend of a dextral fault, the South Korean Tectonic Line. It is the major structural discontinuity between the Okcheon Group (Proterozoic) and the Joseon Supergroup (Lower Paleozoic). The collisional offset between the Gyeonggi Massif (South China Block) and the Yeongnam Massif (Sino-Korean Block) most likely occurred in the Jurassic prior to the emplacement of the mafic dyke and amphibolite.

Zircon grains separated from a granitic gneiss boulder of the Hwanggangri Formation, Ogcheon metamorphic belt, were analyzed using a SHRIMP II ion microprobe. This gravel-bearing formation consists primarily of greenschist to amphibolite facies metadiamictites. U−Pb zircon ages obtained from 31 grains provide not only diachronous inheritance ages ranging up to ca. 2.5 Ga but also define an apparent discordia with upper and lower intercept ages of ca. 1.87 Ga and ca. 290±40 Ma, respectively. The former age is consistent with the Paleoproterozoic age of granu-lite-facies metamorphism and granitic magmatism in the Gyeonggi and Yeongnam massifs. However, the latter age has not been reported from the basement gneisses and may be attributable to significant Pb loss during the Late Carboniferous Ogcheon orogeny recently dated at ca. 290–280 Ma. Alternatively, multiple Pb loss episodes including a ca. 400 Ma thermal disturbance may account for the array of discordant data. The tectonic implications for each hypothesis are enormous for deciphering the evolution of the Ogcheon belt, but precise interpretation awaits further geochronologic analyses.

In order to elucidate metamorphic conditions of metasedimentary rocks of central Ogcheon metamorphic belt, we investigated the b0 parameter and the crystallinity index (CI) of K-white micas from low-grade metapelites. The CI values of muscovite from seventy-eight samples range from 0.08° to 0.19° Δ2θ with an average of 0.12±0.01° Δ2θ, and show no remarkable difference between structurally upper Pibanryeong and lower Poeun lithotectonic units. Slate and phyllite of the Poeun unit have the b0 parameters of 8.993–9.031 A with an average of 9.010±0.007 A (n=63), whereas those in the vicinity of Poeun granite have slightly lower values of 8.988–9.010 A with an average of 8.998±0.006 A (n=33). On the other hand, b0 parameters of pelitic schists in the Pibanryeong unit vary from 8.995 A to 9.042 A (n=29) with an average of 9.009±0.013 A that is similar to 9.003±0.009 A (n=26) in the Poeun unit. These results suggest that low-grade metapelites of central Ogcheon metamorphic belt have experienced a mediumpressure type metamorphism, reaching up to the upper greenschist facies (biotite zone) condition. Moreover, metamorphic pressures estimated from the b0 values show no apparent discontinuity across the unit boundary, implying an insignificant vertical displacement along this boundary after the peak metamorphism.

Metasedimentary rocks in the Miwon area of the central Ogcheon metamorphic belt (OMB) are composed of schist, phyllite, slate, quartzite, and marble, together with minor mafic and felsic layers, and are divided into Pibanryeong and Poeun units. Mineral assemblages of the Poeun unit are represented by low-grade assemblages including biotite and chlorite, whereas those of the Pibanryeong unit by kyanite, staurolite, garnet, and biotite. Retrograde minerals include chlorite and white mica. Subsequent to regional metamorphism, thermal flux during the Mesozoic magmatism produced sillimanite, andalusite, cordierite, staurolite, garnet, biotite, and white mica in the contact aureole. Contact metamorphism, however, did not broadly reset mineral compositions of the regional metamorphism. P-T conditions for regional metamorphism of the Pibanryeong unit are in the range of 4.3–8.0 kbar and 510–620°C, which belong to the kyanite stability field. Mineral assemblages and P-T conditions of the Pibanryeong unit in the Miwon area are identical to those reported in the Jeungpyeoung—Deokpyeong area. However, mineral assemblages of the Poeun unit in both areas are not compatible, and suggest a decrease in metamorphic grade towards the southwest along strike of the OMB.