Labor Market in Ulsan Area

본 논문에서는 이용가능한 부분적인 자료를 이용하여 울산지역 노동시장의 현황과 특성을 파악하고, 이를 바탕으로 실업방지 및 노사관계안정을 위한 앞으로의 과제를 제시하려고 하였다. 울산지역의 노동시장은 대기업 중심의 남성노동시장으로소 강력한 노동조합이 존재하록 있으며, 그 결과 대기업부문과 중소기업부문 사이에 임금을 비롯한 고용조건면에서 분단 노동시장적 성격이 강하게 나타나고 있다. 이러한 지역적인 특성을 고려할 때, 울산지역 노동시장의 안정을 위해서는 대기업의 고용능력 유지가 필수적이며, 동시에 지방정부 및 노동 관련기관에 의한 적극적인 고용안정 및 실업방지 대책이 필요한 것으로 보인다.This paper investigates the current situations and characteristics of labor market in Ulsan area by using obtainable, fragmentary data. We infer that labor market in the area can be characterized as a male-oriented one with military unionism, and this characteristic, at least partially, incurs segmentation of labor markets across firm sizes, especially between large firms and small and medium-sized ones. In order to recover and maintain the stability of labor market in the area, we need to enhance large firms' ability to absorb unemployed workers and new entrants in the local labor market. In addition, we need to increase efficiency and effectiveness of policies in local government and labor-related institutions.This paper investigates the current situations and characteristics of labor market in Ulsan area by using obtainable, fragmentary data. We infer that labor market in the area can be characterized as a male-oriented one with military unionism, and this characteristic, at least partially, incurs segmentation of labor markets across firm sizes, especially between large firms and small and medium-sized ones. In order to recover and maintain the stability of labor market in the area, we need to enhance large firms' ability to absorb unemployed workers and new entrants in the local labor market. In addition, we need to increase efficiency and effectiveness of policies in local government and labor-related institutions

평판형 이온전리함의 자기장에서의 방사선량적 반응

학위논문 (박사)-- 서울대학교 대학원 : 융합과학기술대학원 융합과학부, 2018. 8. 예성준.Radiation dosimetry has been an important issue since the discovery of X-ray. These days, the primary standards dosimetry laboratories (PSDLs) and international agencies (e.g., IAEA, WHO) disseminate the international calibration standards to users through a network of the secondary standards dosimetry laboratories (SSDL). For this purpose, various dosimeters and equipment have been developed to assure the quality of calibration traceability and accuracy. Among them, an ionization chamber has become the most relevant dosimeter for measurements of radiation doses due to its high precision and reliability. Therefore, ionization chambers have been used to provide reference dosimetry calibrations for radiotherapy. Dosimetry for magnetic resonance imaging (MRI)-guided radiotherapy has been an emerging issue in the medical radiation society. Currently developing MRI-guided radiotherapy machines adopt Co-60 or pulsed X-rays with a magnetic field of 0.35 to 1.5 T either perpendicular or parallel to the incident photon beams. The magnetic field influences the trajectories of secondary charged particles through the action of the Lorentz force such that the dose distribution in the sensitive volume of ionization chamber can be altered. Since PSDLs or SSDLs calibrate ionization chambers without a magnetic field, radiation dosimetry in a magnetic field using the ionization chambers needs an additional magnetic field correction factor. Since MRI-guided radiotherapy is still under development, these magnetic field correction factors are often calculated using Monte Carlo (MC) radiation transport codes integrated with an electromagnetic module. In order to evaluate the accuracy of electron transport algorithms of the MC codes at a static magnetic field of 0.35 to 3.0 T, the Fano cavity theorem was tested for mono-energetic electrons with energies ranging from 0.01 to 3 MeV. Four general-purpose Monte Carlo codes (EGSnrc, PENELOPE, MCNP6, and Geant4) were validated for this purpose. With transport parameters carefully selected, PENELOPE and MCNP6 could achieve the accuracy within 1.0% and 0.4%, respectively. Geant4 showed the accuracy within 1.7% except in 3.0 T. The accuracy of EGSnrc with the enhanced electromagnetic field macros was within 0.2%. Owing to its superior accuracy, the following simulations in this study were performed using EGSnrc with the enhanced electromagnetic field macros. The purpose of this study was to calculate magnetic field correction factors of ionization chambers for combinations of various energies of photon beams and various strengths of magnetic fields either perpendicular or parallel to the incident photon beam. Parallel plate ionization chambers are usually used to measure the absorbed dose to water at low-energy beams for radiotherapy. It is advantageous when measuring surface doses to water and doses in a high dose gradient region, and has an easy design customization and fabrication. Three commercial parallel plate ionization chambers were selected to simulate the response variations in a magnetic field. They included the IBA NACP-02, PTW Roos (Type 34001), and Exradin A11. These chambers have the same height but different radii of the sensitive volume. For radiation sources, Eldorado 6 for a Co-60 beam as well as Varian Clinac® series for 6, 10, and 15 MV photon beams were adopted. A spectral source for a 7 MV photon beam adopted in the previous study for the MRI-guided radiotherapy machine was also simulated. The strengths of magnetic field ranged from 0.35 T to 1.5 T, which was either perpendicular or parallel to the photon beam. The responses of the parallel plate ionization chambers in magnetic fields increased by up to 18% compared to those without a magnetic field. The magnetic field correction factors of the parallel plate ionization chambers were 0.85 to 1.0. Large beam quality dependence and variation occurred in cases of the perpendicular orientation. The larger beam quality was applied, the smaller amount of magnetic field corrections were needed. Except for a Co-60 beam, the largest magnetic field correction occurred around 1.0 T rather than 1.5 T, which was the largest magnetic field strength in this study. In cases of the parallel orientation, only small magnetic field corrections less than 1% were needed. The MC calculations for segmentation of the sensitive volume of the ionization chamber showed a strong heterogeneity of the absorbed dose due to helical motions of secondary electrons in the sensitive volume. The sensitive volume of the Roos chamber was in silico modified by half or twice the radius or height to figure out the relationship between the sensitive volume and magnetic field correction. The ionization chamber with a small sensitive volume was less influenced by a magnetic field.1. Introduction 1 2. Materials and Methods 7 2.1. MR-Linac for Radiotherapy 7 2.2. Simulations of Linac and Co-60 Irradiator 10 2.3. Parallel Plate Ionization Chambers 13 2.4. Fano Cavity Tests in Magnetic Fields 16 2.4.1. EGSnrc 22 2.4.2. PENELOPE 22 2.4.3. MCNP6 23 2.4.4. Geant4 25 2.5. Beam Quality Specifier and Beam Quality Conversion Factors 26 2.6. Magnetic Field Correction Factors 28 2.7. Dose Heterogeneity in the Sensitive Volume of the Chambers in a Magnetic Field 28 3. Results 30 3.1. The Fano Cavity Tests 30 3.1.1. EGSnrc 30 3.1.2. PENELOPE 34 3.1.3. MCNP6 36 3.1.4. Geant4 39 3.2. Summary of the Fano Cavity Tests 41 3.3. Simulations of the Linac and Co-60 Beams and Beam Quality Conversion Factors 42 3.4. Response of Parallel Plate Ionization Chambers in a Magnetic Field and Magnetic Field Correction Factors 44 3.5. Dose Heterogeneity within the Sensitive Volume of Chamber in a Magnetic field 51 4. Discussion 56 5. Conclusions 63 Appendix A. Feasibility of a Parallel Plate Ionization Chamber with Graphene Electrodes 65 Bibliography 98 Abstract in Korean 108Docto

APPARATUS FOR RESOURCE ALLOCATION OF BASESTATION BASED ON TRAFFIC PATTERN INFORMATION AND METHOD THEREOF

본 발명은 트래픽 속성 기반 기지국 자원 할당 기술에 관한 것으로, 초소형 기지국이 매크로 기지국의 자원을 공유하여 사용하는 경우, 초소형 기지국이 매크로 기지국의 부 대역별 트래픽 특성 정보를 바탕으로 홉핑을 수행하여 자원을 공유하는 것을 특징으로 한다. 본 발명에 의하면, 초소형 기지국이 매크로 기지국의 자원을 공유하여 사용할 때 트래픽 특성 정보를 활용하여 자원을 공유함으로써, 균일 랜덤 홉핑 방안 및 직접 채널 간섭 측정 방법에 비하여 우수한 자원 사용 효율을 나타낼 수 있다

Distributive Justice in Public Utility Pricing: Foreign Cases and Comparative Analysis

주요 선진국의 공익기업의 민영화 및 공공요금정책에 대한 개괄적인 분석으로부터 알 수 있는 사실은 현재의 추세가 형평성을 중시하던 입장에서 효율성을 중시하는 입장으로 전환되고 있다는 점이다. 효율성의 향상이 형평성 내지 배분적 정의의 실현을 수반한다면 더 바랄 것이 없지만 형평성과 효율성은 상충관계를 지니는 경우가 많다. 따라서 공익기업의 효율화를 둘러싼 논의에서 형평성 문제는 결코 간과되어서는 안될 것이다.This paper analyzed the recent development in privatization of public utilities and pricing policies of major developed countries. A general implication of the analysis is that there is a changing trend from the perspective of equity to that of efficiency. The problem is the usual trade-off relationship between efficiency and equity. Privatization and development of new pricing method are important ongoing issues in Korea. Efficiency is, of course, a major criterion around those issues, but we have to emphasize equity as a criterion of equivalent importance.This paper analyzed the recent development in privatization of public utilities and pricing policies of major developed countries. A general implication of the analysis is that there is a changing trend from the perspective of equity to that of efficiency. The problem is the usual trade-off relationship between efficiency and equity. Privatization and development of new pricing method are important ongoing issues in Korea. Efficiency is, of course, a major criterion around those issues, but we have to emphasize equity as a criterion of equivalent importance

Social Welfare System and the Basic Conditions for Quality of Life: A Comparative Study from a Perspective of Distributive Justice

본 논문에서는 한국의 사회복지제도가 추구하는 이념과 삶의 질을 보장하기 위한 기초여건의 실태를 분석한다. 논문의 전반부에서는 사회복지제도에 대한 자유주의적 이론, 공리주의적 이론, 사회민주주의 및 마르크스주의, 그리고 형평이론을 간략히 소개한다. 이어 서구 선진국들간의 비교를 통하여 각 국가가 추구하는 이념을 비교한다. 국가간 비교를 위하여 사회민주주의를 표방하고 있는 스웨덴과 노르웨이, 보수적 입장의 독일과 오스트리아, 급진적인 입장의 호주와 뉴질랜드, 그리고 자유주의적 이념을 추구하는 캐나다와 미국을 주요 비교의 대상으로 선정하였다. 그 외에도 한국의 복지실태를 조망할 수 있는 준거의 틀로서 아시아 국가인 일본, 홍콩, 및 싱가포르를 포함시켰다. 마지막으로 위의 국가들과 한국의 국가에 대한 국민들의 기여, 경제여건 및 고용의 안정성, 건강 및 사회보장, 교육, 사회적 스트레스 및 안전, 인간발달지수 및 환경조건 등을 비교함으로써 한국의 삶의 질을 위한 기초여건의 형평성을 고찰하였다.This study analyzes Korea's welfare system and its basic conditions for securing quality of life. The first part of the study briefly reviews various theories on social welfare: liberal theory, utilitarian theory, social democratic theory and the Marxist theory, and equity theory. The second part compares the ideals and goals that the 8 chosen European nations pursue with their own welfare systems. The nations employed in the comparison are Sweden and Norway with a social democratic ideal, Germany and Austria with a conservative ideal, Australia and New Zealand with a radical ideal, and Canada and the U.S. with a liberal ideal. In addition to the 8 nations, 3 Asian nations, Japan, Hong Kong, and Singapore, are included for a more direct and comprehensive comparison with Korea. The last part analyzes the degree of fairness of exchange between people and the government by comparing such indices as financial and labor contributions to the government, economic condition and employment, health and social insurance programs, education, social stress and safety, human development indices and environment of Korea with those of the chosen countries.This study analyzes Korea's welfare system and its basic conditions for securing quality of life. The first part of the study briefly reviews various theories on social welfare: liberal theory, utilitarian theory, social democratic theory and the Marxist theory, and equity theory. The second part compares the ideals and goals that the 8 chosen European nations pursue with their own welfare systems. The nations employed in the comparison are Sweden and Norway with a social democratic ideal, Germany and Austria with a conservative ideal, Australia and New Zealand with a radical ideal, and Canada and the U.S. with a liberal ideal. In addition to the 8 nations, 3 Asian nations, Japan, Hong Kong, and Singapore, are included for a more direct and comprehensive comparison with Korea. The last part analyzes the degree of fairness of exchange between people and the government by comparing such indices as financial and labor contributions to the government, economic condition and employment, health and social insurance programs, education, social stress and safety, human development indices and environment of Korea with those of the chosen countries

Fast route recovery methods for cellular IP access network

학위논문(석사) - 한국과학기술원 : 전기및전자공학전공, 2004.8, [ vii, 50 p. ]셀간 잦은 핸드오프로 발생하는 시그널링 지연을 줄이기 위해 계층적 이동성 관리 모델이 도입되었다. 계층적 이동성 관리 모델에서 이동 단말의 macro level 이동성을 지원해 주기 위해 현재 Mobile IP가 표준화 중에 있다. Cellular IP는 무선 접속망 내부에서 이동 단말의 micro level 이동성을 지원해 준다. Cellular IP는 이동 단말의 위치 관리를 위해 호스트 기반 라우팅 기법을 사용한다. 그러나 Cellular IP는 내부 노드간 링크 파손이 발생했을 때, 이동 단말에게 전달되는 트래픽의 단절 현상이 발생한다. 이러한 신뢰성 문제를 위해, Cellular IP에서는 "게이트웨이 브로드캐스트 패킷"이라는 비콘 패킷을 사용한다. 이 패킷은 긴시간의 주기를 가지고 브르드캐스트된다. 또한 Cellular IP는 이동 단말을 위한 빠르고 동적인 경로 회복 기법을 제공하고 있지 않다. 본 논문에서는 Cellular IP 접속망 내부에서 링크 파손시 각 단말의 위치 정보를 갱신할 수 있는 빠른 방법을 제안한다. 페이징을 사용하는 경로 회복 기법, 망 노드가 시작하는 경로 회복 기법 및 단말이 시작하는 경로 회복 기법 등의 세 가지 관점에서 경로 회복 기법을 제안했다. ns-2 모의 실험을 통해 세가지 방법을 경로 회복 시간, 경로 회복 시간 동안의 패킷 손실, 제어 패킷 오버헤드 측면에서 비교하였다. 두번째 방법이 가장 빠르지만, Cellular IP 내부 노드들이 복잡해질 필요가 있다. 나머지 방법들은 간단하지만, 프로토콜의 타이머 값들에 의존적이다. 그러나 이 값들은 게이트웨이 브로드캐스트 패킷의 주기보다 훨씬 짧은 값이다.한국과학기술원 : 전기및전자공학전공

Morphometric analysis of the anterior region of the maxillary bone for immediate implant placement using micro-CT

The purpose of this study was to elucidate the relationship between the maxillary incisor roots and surrounding alveolar structures using microscopic computerized tomography (micro-CT) for the immediate implant placement. Nineteen maxillae from 14 Korean cadavers were used in this study. All specimens were scanned and reconstructed into a three-dimensional (3D) structure using a micro-CT system. The roots of the maxillary central and lateral incisors became dramatically narrower from 6 mm above the cementoenamel junctions to the apex. The roots of the maxillary incisors and canine were located at the labial one fifths region of the alveolar bone. The angle formed by the longitudinal root axis and the alveolar bone was greatest at the maxillary canine. On the basis of the results of this study, guidelines for immediate implant placement can be suggested on the implant diameter and drilling angle to minimize damage of the alveolar plate.ope