• Title/Summary/Keyword: knowledge variation

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Maxillary first molar with 7 root canals diagnosed using cone-beam computed tomography

  • Rodrigues, Evaldo;Braitt, Antonio Henrique;Galvao, Bruno Ferraz;da Silva, Emmanuel Joao Nogueira Leal
    • Restorative Dentistry and Endodontics
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    • v.42 no.1
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    • pp.60-64
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    • 2017
  • Root canal anatomy is complex, and the recognition of anatomic variations could be a challenge for clinicians. This case report describes the importance of cone beam computed tomographyic (CBCT) imaging during endodontic treatment. A 23 year old woman was referred by her general dental practitioner with the chief complaint of spontaneous pain in her right posterior maxilla. From the clinical and radiographic findings, a diagnosis of symptomatic irreversible pulpitis was made and endodontic treatment was suggested to the patient. The patient underwent CBCT examination, and CBCT scan slices revealed seven canals: three mesiobuccal (MB1, MB2, and MB3), two distobuccal (DB1 and DB2), and two palatal (P1 and P2). Canals were successfully treated with reciprocating files and filled using single-cone filling technique. Precise knowledge of root canal morphology and its variation is important during root canal treatment. CBCT examination is an excellent tool for identifying and managing these complex root canal systems.

The Control of A Ball Beam Using Fuzzy Control in Vision (화상의 퍼지 알고리즘 처리를 통한 공과 막대 시스템 제어)

  • Park, Seung-Hun;Joo, Han-Jo;Yim, Wha-Yoeng
    • Proceedings of the KIEE Conference
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    • 2003.11c
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    • pp.965-967
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    • 2003
  • Fuzzy Controller is a system that displays a person's thoughts using membership function and IF-THEN rules. With the help of specialists' knowledge, rule bases can be explained in easy language. Furthermore Fuzzy Controller has strong resistance against turbulence. Its performance is especially prominent when targets cannot be measured in mathematic methods because the fuzzy controller can measure the output using only the relations between the input and output. With the increasing influence of multimedia on our daily lives, vision plays bigger role both in industries and personal lives. Like wise vision is being used in many areas such as detecting and identifying objects. It is difficult to detect and control targets because there is a delay in the calculating when using vision in detecting and controlling objects in large quantity. In this paper we showed how to use fuzzy controller in minimizing the calculation process, controlling target objects and moving view window instead of applying input variation through vision. Ball beam, which has strong nonlinear, was used as the target object and DSP320C6711 IDK by TI(Texas Instruments) company was for the benefit of speedy calculation and vision data operation.

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Investigation of Cutting Characteristics in the Sharp Comer for the Case of Cutting of Inconel 718 Super-alloy Sheet Using High-power CW Nd:YAG Laser (고출력 CW Nd:YAG 레이저를 이용한 인코넬 718 판재 절단시 모서리부 절단 특성 분석)

  • Ahn, Dong-Gyu;Byun, Kyung-Won
    • Journal of Welding and Joining
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    • v.26 no.5
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    • pp.90-96
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    • 2008
  • The objective of this paper is to investigate the effects of the laser power, the material thickness, comer angles, and the loop size on the formation of the comer in the cutting of Inconel 718 super-alloy sheet using high-power CW Nd: YAG laser. In order to investigate the influence of comer angles and loop sizes on the melted area and the formation of comer in the sharp comer, angular cutting tests and loop cutting tests were carried out. The results of the angular cutting tests were shown that the melted area is minimized and the melting mode is changed from nose melting in the thickness direction to the secondary melting induced by the attached dross when the comer angle is $90^{\circ}$. Through the results of loop cutting tests, the variation of the melted area and the comer shape in the sharp comer according to the loop size were examined. In addition, it was shown that a proper loop size is approximately 3 mm. The results of above experiments will be reflected on the knowledge base to generate optimal cutting path of the laser.

X-linked adrenoleukodystrophy; Recent Advances in Classification, Diagnosis and Management (X 연관 부신백질이영양증의 분류, 진단 및 치료의 최신 지견)

  • Jung, Eul Sik;Ko, Ara;Kang, Hoon-Chul
    • Journal of the Korean Child Neurology Society
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    • v.24 no.3
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    • pp.71-83
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    • 2016
  • X-linked adrenoleukodystrophy (X-ALD) is caused by mutations in the ATP binding cassette subfamily D member 1 (ABCD1), a gene that encodes peroxisomal membrane located on ABC half-transporter named adrenoleukodystrophy protein (ALDP). X-ALD is characterized by a highly variable clinical spectrum, including progressive cerebral type, adrenomyeloneuropathy, and addison-only phenotype. No genotype/phenotype correlation has been established. Thus, unidentified modifier genes and other co-factors are speculated to modulate the phenotypic variation and disease severity. Recent advanced sequencing methods and reprogramming technologies not only offer an affordable and applicable approach to investigate the pathophysiological mechanisms of adrenoleukodystrophy, but also provide means to develop therapy. A causal therapy of X-ALD is lacking. Lorenzo's oil therapy is recommended for asymptomatic boys, but the longest study found that the oil was not beneficial at all to symptomatic X-ALD patients. Hematopoietic stem cell therapy has a relevant chance of success when performed during this early stage of cerebral type X-ALD. Recently, it has been insisted that lentiviral-mediated gene therapy of hematopoietic stem cells can provide clinical benefits in X-ALD. This review describes current knowledge on the clinical presentation, pathogenesis, diagnosis and management of X- ALD.

Effects of Uncertain Spatial Data Representation on Multi-source Data Fusion: A Case Study for Landslide Hazard Mapping

  • Park No-Wook;Chi Kwang-Hoon;Kwon Byung-Doo
    • Korean Journal of Remote Sensing
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    • v.21 no.5
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    • pp.393-404
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    • 2005
  • As multi-source spatial data fusion mainly deal with various types of spatial data which are specific representations of real world with unequal reliability and incomplete knowledge, proper data representation and uncertainty analysis become more important. In relation to this problem, this paper presents and applies an advanced data representation methodology for different types of spatial data such as categorical and continuous data. To account for the uncertainties of both categorical data and continuous data, fuzzy boundary representation and smoothed kernel density estimation within a fuzzy logic framework are adopted, respectively. To investigate the effects of those data representation on final fusion results, a case study for landslide hazard mapping was carried out on multi-source spatial data sets from Jangheung, Korea. The case study results obtained from the proposed schemes were compared with the results obtained by traditional crisp boundary representation and categorized continuous data representation methods. From the case study results, the proposed scheme showed improved prediction rates than traditional methods and different representation setting resulted in the variation of prediction rates.

Influences of Power Fluctuation on In-Situ Ground Thermal Response Testing (지중 열반응 현장시험에서 소비전력 변동의 영향)

  • Kim, Jin-Sang;Park, Keun-Woo
    • Proceedings of the SAREK Conference
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    • 2006.06a
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    • pp.707-712
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    • 2006
  • Knowing the ground thermal conductivity is very importnat in designing ground heat exchangers. Knowledge of the ground soil and rock composition information dose not guarantee the prediction of accurate thermal information. In Situ testing of ground heat exchangers is becoming popular. However, in situ testing are performed at construction sites in real life. Adequate data collection and analysis are not easy mainly due to poor power quality. Power fluctuation also causes the fluctuation of received data. The power quality must be maintained during the entire in situ testing processes. To accurately analyse the test data, the understanding of the response of the power fluctuation is essential. Testing under the power quality varied by tester is very difficult. Analyzing power variation by numerical simulation is a realistic option. By varying power in a sinosuidal manner, its effects on predicting thermal conductivity from thermal response plots made from the test data are examined.

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Parametric study for enhanced performance of Cu and Ni electrowinning

  • Kim, Joohyun;Kim, Han S.;Bae, Sungjun
    • Membrane and Water Treatment
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    • v.10 no.3
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    • pp.201-206
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    • 2019
  • In this study, we performed an electrowinning process for effective removal of metals (Cu and Ni) in solution and their recovery as solid forms. A complete removal of Cu and Ni (1,000 mg/L) was observed during four times recycling test, indicating that our electrowinning system can ensure the efficient metal removal with high stability and durability. In addition, we investigated effect of operation parameters (i.e., concentration of boric acid only for Ni, variation of pH, concentration of electrolyte ($H_2SO_4$), and cell voltage) on the efficiency of metal removal (Cu and Ni) during the electrowinning. The addition of boric acid significantly enhanced removal efficiency of Ni as the concentration of boric acid increased up to 10 g/L. Compared to negligible pH effect (pH 1, 2, and 4) on the Cu removal, we observed the increase in removal efficiency of Ni as the pH increased from 1 to 4. The electrolyte concentration did not significantly influence the removal of Cu and Ni in this study. We also obtained great removal rates of Cu and Ni at 2.5 V and 4.0 V, which were much faster than those at lower voltages. Finally, almost 99% of each Cu and Ni (1,000 mg/L) was selectively removed from the mixture of metals by adjusting pH and addition of boric acid after the completion of Cu removal. The findings in this study can provide a fundamental knowledge about effect of important parameters on the efficiency of metal recovery during the electrowinning.

Current Status of 'Professional Identity Formation' Education in the Medical Professionalism Curriculum in Korea (우리나라 의학전문직업성 교육과정에서의 '전문직 정체성 형성' 교육 현황)

  • Lee, Young-Hee
    • Korean Medical Education Review
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    • v.23 no.2
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    • pp.90-103
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    • 2021
  • This study examined the current status of the medical professionalism curriculum in Korea to suggest a plan to move towards the formation of a professional identity. Professionalism education data from 28 Korean medical schools were analyzed, including the number of courses, required or elective status, corresponding credits, major course contents, and teaching and evaluation methods. Considerable variation was found in the number of courses and credits in the professionalism curriculum between medical schools. The course contents were structured to expand learners' experiences, including the essence and knowledge of professionalism, understanding of oneself, social interaction with others, and the role of doctors in society and the healthcare system. The most common teaching methods were lectures and discussions, while reflective writing, coaching, feedback, and role models were used by fewer than 50% of medical schools. Written tests, assignments and reports, discussions, and presentations were frequently used as evaluation methods, but portfolio and self-evaluation rates were relatively low. White coat ceremonies were conducted in 96.2% of medical schools, and 22.2% had no code of conduct. Based on the above results, the author suggests that professional identity formation should be explicitly included in learning outcomes and educational contents, and that professional identity formation courses need to be added to each year of the program. The author also proposes the need to expand teaching methods such as reflective writing, feedback, dilemma discussion, and positive role models, to incorporate various evaluation methods such as portfolios, self-assessment, and moral reasoning, and to strengthen faculty development.

Digital engineering models for prefabricated bridge piers

  • Nguyen, Duy-Cuong;Park, Seong-Jun;Shim, Chang-Su
    • Smart Structures and Systems
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    • v.30 no.1
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    • pp.35-47
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    • 2022
  • Data-driven engineering is crucial for information delivery between design, fabrication, assembly, and maintenance of prefabricated structures. Design for manufacturing and assembly (DfMA) is a critical methodology for prefabricated bridge structures. In this study, a novel concept of digital engineering model that combined existing knowledge of DfMA with object-oriented parametric modeling technologies was developed. Three-dimensional (3D) geometry models and their data models for each phase of a construction project were defined for information delivery. Digital design models were used for conceptual design, including aesthetic consideration and possible variation during fabrication and assembly. The seismic performance of a bridge pier was evaluated by linking the design parameters to the calculated moment-curvature curves. Control parameters were selected to consider the tolerance control and revision of the digital models. Digitalized fabrication of the prefabricated members was realized using the digital fabrication model with G-code for a concrete printer or a robot. The fabrication error was evaluated and the design digital models were updated. The revised fabrication models were used in the preassembly simulation to guarantee constructability. For the maintenance of the bridge, the as-built information was defined for the prefabricated bridge piers. The results of this process revealed that data-driven information delivery is crucial for lifecycle management of prefabricated bridge piers.

Diversity and distribution of invasive alien plant species along elevation gradient in Makawanpur district, central Nepal

  • Dipesh Karki;Bijay Pandeya;Balkrishna Ghimire
    • Journal of Ecology and Environment
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    • v.47 no.3
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    • pp.75-84
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    • 2023
  • Background: Knowledge of the spatial trends of plant invasions in different habitats is essential for a better understanding of the process of these invasions. We examined the variation in invasive alien plant species (IAS) richness and composition at two spatial scales defined by elevation and habitat types (roadside, forest, and cultivated lands) in the Makawanpur district of Nepal. Following an elevation gradient ranging from 500 to 2,400 m asl along a mountain road, plant species cover was recorded within sample plots of size 10 m × 5 m. Systematic random sampling was adopted in every 100 m elevation intervals on three habitat types. Results: Altogether 18 invasive alien plants belonging to eight families were recorded within 60 plots, of which 14 species (representing 80%) were from tropical North and South America. The most common plants by their frequency were Ageratina adenophora, Chromolaena odorata, Bidens pilosa, Lantana camara, and Parthenium hysterophorus. We found a significant relationship between species composition and elevation in the study area. Low-elevation regions had a higher number of alien species as compared to high-elevation regions within different habitat types. Conclusions: The species richness and density of IAS were higher in the road site followed by the cultivated land and forest sites. This pattern occurred throughout the elevation range and habitats. IAS were found mostly in the open land with high sunlight availability. Information from such scientific assessment of invasive alien plants will assist in developing appropriate management plans in the Makawanpur district.