다상 유도 전동기는 전력 변환 효율이 높은 전동기이다. 이와 같은 고효율 전동 기는 다양한 산업의 전기 수요가 증가하면서 더 필요한 상황이다. 이러한 상황에서 기업이나 국가가 적절한 전략을 세우기 위해 다상 유도 전동기 기술의 현 위치 확인과 미래 예측이 필 요하다. 다상 유도 전동기의 현 위치 파악과 미래 기술을 탐색하기 위해, 본 연구는 특허 네 트워크 경로 분석을 1902년부터 2024년까지의 특허 중 기술분류명(CPC H02K17/12 : 다상 비동기 유도전동기)에 적용한다. 그 결과, 미국과 유럽 기업이 전반적인 기술 개발을 주도하 였으며, 2010년 이후 중국 기업이 기술 개발을 급격히 늘렸음을 확인하였다. 네트워크 군집 분석 결과, 기계적 구조 개선 기술(전기 권선 및 극수 변환), 전기적 연결 기술(전류 파형 및 순서 변경), 스마트 융합 기술(센서+전기제어+전동기 구조 개선)의 세 가지 군집이 확인되었 다. 핵심 기술 경로 분석 결과, 일반적으로 인식하는 경쟁 우위 기업과 실제 기술적 영향력이 있는 기업 간의 차이가 존재했다.

The aim of this study was to calculate the health risks which children were exposed to trace metals through several pathways including air, floor dust, wipe and hand wipes in elementary-schools and academies. The samples were collected at children's facilities (50 elementary-schools and 46 academies) in summer (Aug ~ Sept, 2008), winter (Dec 2008 ~ Feb, 2009) and Spring (Mar ~ Apr, 2009) periods. The lifetime Excess Cancer Risks (ECRs) were estimated for carcinogen trace elements such as As, Cd, and Cr. For carcinogens, the Excess Cancer Risk (ECR) was calculated by considering the process of deciding Cancer Potency Factor (CPF) and Age Dependent Adjust Factor (ADAF) of the data of adults. Hazard Quotients (HQs) were estimated for the non-carcinogens trace metals like Cd, Cr, Hg and Pb. The average ECRs for young children were 1×10^-9~1×10^-8 (50%th percentile) level in all facilities. Non-carcinogens did not exceed 0.1 for all subjects in all facilities. For trace metals their risk based on health risk assessment was also observed to be acceptable.

This study assessed the health risk of trace elements in indoor children-facilities by multi-pathway measurements (Air, Dust, Wipe, Hand washing). The samples of indoor place were collected at various children's facilities (40 day-care houses, 42 child-care centers, 44 kindergartens, and 42 indoor playgrounds) in summer (Jul~Sep, 2007) and winter (Jan~Feb, 2008) periods, and analyzed by ICP-MS. The lifetime Excess Cancer Risks (ECRs) were estimated for carcinogen trace elements such as As, Cd, Cr and Ni. For carcinogens, the Excess Cancer Risk (ECR) was calculated by considering the process of deciding Cancer Potency Factor (CPF) and Age Dependent Adjust Factor (ADAF) of the data of adults. Both Hazard Quotients (HQs) and Hazard Index (HI) were estimated for the non-carcinogens and children sensitivity trace elements like Cd, Cu, and Cr. The average ECRs for young children were 1×10^-10~1×10^-6 (50%th percentile) level in all facilities. Non-carcinogens and Children's sensitivity materials did not exceed 1.0 (HQs, HI) for all subjects in all facilities. For trace elements their detection rates through multi-pathways were not high and their risk based on health risk assessment was also observed to be acceptable. In addition, through education on the risk of multi-pathway exposure of trace elements for managers of facilities as well as for users the risk control of exposure of children.