Powder quality, including high flowability and spherical shape, determines the properties of additively manufactured products. Therefore, the cheap production of high-quality powders is critical in additive manufacturing. Radio frequency plasma treatment is an effective method to fabricate spherical powders by melting the surface of irregularly shaped powders; in the present work, mechanically milled Zr powders are spheroidized by radio frequency plasma treatment and their properties are compared with those of commercial Zircaloy-2 alloy powder. Spherical Zr particles are successfully fabricated by plasma treatment, although their flowability and impurity contents are poorer than those of the commercial Zircaloy-2 alloy powder. This result shows that radio-frequency plasma treatment with mechanically milled powders requires further research and development for manufacturing low-cost powders for additive manufacturing.

Worldwide, oral cancer accounts for 2%–4% of all cancer cases. It is estimated that more of 90% of all oral neoplasms are oral squamous cell carcinoma (OSCC). The aims of this study were to evaluate follow-up outcomes in patients with OSCC invading the mandibular body bone who underwent primary radical resection and reconstructive surgery by fibular free flap or CAD-CAM T-mesh with pathological study on two cases. In this article, two cases of mandibular reconstruction in patients with OSCC invading the mandibular body bone are reported. A 68-year-old male patient visited the authors’ clinic with pain on the left mandibular region. After wide excision and segmental mandibulectomy on the mandibular OSCC, a enterocutaneous fibular free flap from right leg was used to cover the intraoral mucosal defect. The other 51-year-old female patient visited the authors’ clinic with pain on the right mandibular region. After wide excision and segmental mandibulectomy on the mandibular OSCC, reconstruction was done with a reconstruction plate and a fibula free flap from right leg. Unfortunately, fibular free flap was lost due to infection of the flap at post-operative 1month, secondary reconstruction using a custom-made type T-mesh and iliac PCBM was done to repair on the mandibular defect after four years postoperatively. The customized CAD-CAM T-mesh was made prior to the operation according to mirror image of remained jaw. Patients with OSCC invading the mandibular body bone are required an accurate segmental mandibulectomy immediate reconstructive surgery with various methods and followed by adjuvant radiation with or without chemotherapy in order to improve the quality of life through the restoration of the oral function and esthetics after surgery. Postoperative CCRT was determined according to the final pathologic findings such as lymph node metastasis and main lesion free margin safety, and this has an essential relationship in the prognosis of postoperative recurrence. We reviewed reliable treatment options on two patients of OSCC in mandible with pathologic findings.Worldwide, oral cancer accounts for 2%–4% of all cancer cases. It is estimated that more of 90% of all oral neoplasms are oral squamous cell carcinoma (OSCC). The aims of this study were to evaluate follow-up outcomes in patients with OSCC invading the mandibular body bone who underwent primary radical resection and reconstructive surgery by fibular free flap or CAD-CAM T-mesh with pathological study on two cases. In this article, two cases of mandibular reconstruction in patients with OSCC invading the mandibular body bone are reported. A 68-year-old male patient visited the authors’ clinic with pain on the left mandibular region. After wide excision and segmental mandibulectomy on the mandibular OSCC, a enterocutaneous fibular free flap from right leg was used to cover the intraoral mucosal defect. The other 51-year-old female patient visited the authors’ clinic with pain on the right mandibular region. After wide excision and segmental mandibulectomy on the mandibular OSCC, reconstruction was done with a reconstruction plate and a fibula free flap from right leg. Unfortunately, fibular free flap was lost due to infection of the flap at post-operative 1month, secondary reconstruction using a custom-made type T-mesh and iliac PCBM was done to repair on the mandibular defect after four years postoperatively. The customized CAD-CAM T-mesh was made prior to the operation according to mirror image of remained jaw. Patients with OSCC invading the mandibular body bone are required an accurate segmental mandibulectomy immediate reconstructive surgery with various methods and followed by adjuvant radiation with or without chemotherapy in order to improve the quality of life through the restoration of the oral function and esthetics after surgery. Postoperative CCRT was determined according to the final pathologic findings such as lymph node metastasis and main lesion free margin safety, and this has an essential relationship in the prognosis of postoperative recurrence. We reviewed reliable treatment options on two patients of OSCC in mandible with pathologic findings.

Artificial intelligence, has been applied in interpreting osteoporosis on dental panoramic radiograph with high accuracy. The purpose of this study was to investigate the sensitive area of convolutional neural network(CNN), one of artificial intelligence, in interpreting osteoporosis on dental panoramic radiograph. Dental panoramic radiographs taken from 1,170 female (49.19 ±21.91 average age, 21 minimum age, and 84 maximum age) were selected for this study. Two oral maxillofacial radiologists agreed upon interpreting osteoporosis by interpreting mandibular inferior cortical changes. The region of interest included upper and lower jaws for training and testing CNN in interpreting osteoporosis. A filter which was set to look for image characteristics moved through the entire panoramic radiography to identify sensitive areas that distinguish normal groups and osteoporosis patients. In interpreting osteoporosis on panoramic radiograph, CNN responded sensitively at the cancellous bone of the upper and lower jaws while oral maxillofacial radiologists interpreted mandibular inferior cortical change.

PURPOSES : Many people recommend the expansion of the drone market and various ways of using drones. However, unreasonable expansion may cause various social problems. Therefore, criteria and systems for the expansion are required. This paper presents a review of the system using drones for managing and enforcing illegal parking, and recommendations on improvement. METHODS : This paper presents a review of the system using drones for managing and enforcing illegal parking, and recommendations on improvement. RESULTS : This study shows that new enforcement criteria are required for a new enforcement method using drones. In addition, consignment operation is needed to solve workforce shortage and secure expertise, and flight mitigation criteria are required, considering the illegal parking characteristics based on region and time. Finally, CCTV operation guidelines should be improved to clarify the definition of drone images and prevent unreasonable information collection. CONCLUSIONS : Illegal parking enforcement using drones is an efficient method that is highly feasible and solves enforcement limitation issues, such as the lack of workforce and equipment. A prior institutional review is required to apply new technologies more efficiently, and proposals on improving the legal systems with limitations are required through continuous research.

이 연구는 마라톤대회 서비스품질이 서비스가치 및 참여자만족에 미치는 영향을 규명하는데 목적이 있다. 자료분석을 위하여 마라톤대회에 참여하는 참여자를 대상으로 총 350부의 설문지를 배포하였으며, 불성실한 응답 21부를 제외한 총 329(94%)의 자료를 유효표본으로 사용하였다. 자료처리를 위하여 PASW 21.0을 이용하여 빈도분석, 탐색적 요인분석, 신뢰도분석, 다중회귀분석을 실시하였다. 이에 다음과 같은 결과를 도출하였다. 첫째, 마라톤 서비스품질은 서비스가치에 영향을 미쳤다. 둘째, 마라톤 서비스품질은 참여자만족에 영향을 미쳤다. 셋째, 서비스가치는 참여자만족에 영향을 미쳤다.

국내 고농도의 초미세먼지 발생 빈도 증가와 함께 그 전구물질인 NH3와 관련한 연구가 활발히 진행 중이다. NH3 배출에 있어 농업의 기여율이 높은 것은 자명한 사실이다. 그러나 비료 사용이 농경지 대기 중 NH3 농도에 장기간 미치는 영향에 관련한 연구는 미비한 실정이다. 따라서 본 연구에서는 수동식 NH3 확산형 포집기를 활용해 11개월 간 농경지 대기 중 NH3 농도를 관측하였다. 그 결과 비료 살포 직후 한 달 동안 NH3 배출의 영향이 가장 큰 것으로 나타났다. 그 이후 여름철 기온 상승으로 NH3 휘발이 촉진되어 대기 중 농도가 증가할 것으로 예상하였으나, 54일간의 지속적인 강우로 인하여 대기 중 높은 암모니아 농도는 관측되지 않았다. 그 후 NH3 농도는 가을과 겨울을 거치면서 점차 감소하였다. 비료의 영향력이 감쇠한 시점 이후에는 기온이 감소할수록, 그리고 강수량이 증가할수록 NH3 농도는 감소하는 것을 상관분석을 통해 확인할 수 있었다. 종합해 보면, 국내 NH3 배출량에서 비료의 기여율을 연구하는 데 있어 비료 살포 직후 최소 한 달 동안은 집중적으로 살펴보아야 할 것이며, 현장 연구 시 강수량과 무강우 일수 등의 기상 정보도 함께 고려해야 할 것이다.

화상병균(Erwinia amylovora)에 의해 발생하는 과수 화상병은 주로 사과, 배 등의 장미과 식물에서 발병한다. 과수 화상병은 국내에서 금지 병원균으로 지정되어 있으며, 2015년 경기도 안성의 배과수원에서 최초 발견되었다. 그러나, 현재까지 근본적인 방제약제가 없는 상황으로 발생지는 매몰이 최선의 방법으로 여겨진다. 따라서 본 연구에서는 2019년을 기준으로 충북지역의 과수 화상병 발생 원인 분석을 통하여 발생 경로 차단을 위한 역학조사를 실시하였다. 1. 충주시 등 3개 시군의 전체 221농가 141ha에서 과수 화상병이 발생하였으며, 세부적인 연도별 발생현황은 2015년(2농가 1ha), 2018년(74농가 51.5ha), 2019년(145농가 88.9ha) 로 나타났다. 2. 과수 화상병의 발생시기는 주로 5월부터 8월 사이로 나타났으며, 특히 6월(73.8%)이 가장 많이 발생하였으며, 7월 (17.2%), 5월(7.6%), 8월(1.4%)순으로 나타났다. 3. 과수 화상병 발생 의심 신고 후 확진 매몰까지 소요기간은 11.9일이었고, 발생에서 매몰까지의 기간은 최단 5일에서 최장 19일로 조사되었다. 4. 병원균의 최초 발생지로부터의 확산 거리는 평균 21 km로 나타났으며 가장 먼거리는 음성군 비산면으로 34 km였다.

In this study, using the plasma spray method, tensile and compression fatigue tests are performed in saline solution to examine the effect of Ti undercoat on corrosion fatigue behavior of alumina-coated specimens. The alumina-coated material using Ti in the undercoat shows better corrosion fatigue strength than the base material in the entire stress amplitude range. Fatigue cracking of UT specimens occurs in the recess formed by grit-blasting treatment and progresses toward the base metal. Subsequently, the undercoat is destroyed at a stage where the deformation of the undercoat cannot follow the crack opening displacement. The residual stress of the UT specimen has a tensile residual stress up to about 100 μm below the surface of the base material; however, when the depth exceeds 100 μm, the residual stress becomes a compressive residual stress. In addition, the inside of the spray coating film is compressive residual stress, which contributes to improving the fatigue strength characteristics. A hardened layer due to grit-blasting treatment is formed near the surface of the UT specimen, contributing to the improvement of the fatigue strength characteristics. Since the natural potential of Ti spray coating film is slightly higher than that of the base material, it exhibits excellent corrosion resistance; however, when physiological saline intrudes, a galvanic battery is formed and the base material corrodes preferentially.

본 연구에서는 승용차에서 사람들이 기기를 사용하기 위해 사용하는 기동어인 “Hi, KIA!”의 감성을 기계학습을 기반으로 분류가 가능한가에 대해 탐색하였다. 감성 분류를 위해 신남, 화남, 절망, 보통 총 4가지 감정별로 3가지 시나리오를 작성하여, 자동차 운전 상황에서 발생할 수 있는 12가지의 사용자 감정 시나리오를 제작하였다. 시각화 자료를 기반으로 총 9명의 대학생을 대상으로 녹음을 진행하였다. 수집된 녹음 파일의 전체 문장에서 기동어 부분만 별도로 추출하는 과정을 거쳐, 전체 문장 파일, 기동어 파일 총 두 개의 데이터 세트로 정리되었다. 음성 분석에서는 음향 특성을 추출하고 추출된 데이터를 svmRadial 방법을 이용하여 기계 학습 기반의 알고리즘을 제작해, 제작된 알고리즘의 감정 예측 정확성 및 가능성을 파악하였다. 9명의 참여자와 4개의 감정 카테고리를 통틀어 기동어의 정확성(60.19%: 22~81%)과 전체 문장의 정확성(41.51%)을 비교했다. 또한, 참여자 개별로 정확도와 민감도를 확인하였을 때, 성능을 보임을 확인하였으며, 각 사용자 별 기계 학습을 위해 선정된 피쳐들이 유사함을 확인하였다. 본 연구는 기동어만으로도 사용자의 감정 추출과 보이스 인터페이스 개발 시 기동어 감정 파악 기술이 잠재적으로 적용 가능한데 대한 실험적 증거를 제공할 수 있을 것으로 기대한다.

Environmental fundamental facilities have different odor emission characteristics depending on the type of treatment facilities. To overcome the limitations of the olfactometry method, research needs to be conducted on how to calculate the dilution factor from the individual odor concentrations. The aim of this study was to determine the air dilution factor estimated from manually measured concentration data of individual odor substances (22 specified odor species) in three environmental treatment facilities. In order to calculate the optimum algorism for each environmental fundamental facility, three types of facilities were selected, the concentration of odor substances in the exhaust gas was measured, and the contribution of the overall dilution factor was evaluated. To estimate the dilution factor, four to six algorism were induced and evaluated by correlation analysis between substance concentration and complex odor data. Dilution factors from O municipal water treatment (MWT) and Y livestock wastewater treatment (LWT) facilities showed high level of dilution factors, because concentration levels of hydrogen sulfide and methylmercaptan, which had low odor threshold concentrations, were high. In S food waste treatment (FWT) facility, the aldehyde group strongly influenced dilution the factor (dominant substance: acetaldehyde, i-valeraldhyde and methylmercaptan). In the evaluation of four to six algorism to estimate the dilution factor, the vector algorism (described in the text) was optimum for O MWT and Y LWT, while the algorism using the sum of the top-three dominant substances showed the best outcome for S FWT. In further studies, estimation of the dilution factor from simultaneously monitored data by odor sensors will be developed and integrated with the results in this study.