• Title/Summary/Keyword: Mobility Patterns

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A Exploratory Study on Skill Formation and Professionalization of Korea's Newspaper Journalists (한국 신문언론노동의 숙련구조 변동과 전문직화에 대한 탐색적 접근)

  • Choi, Seok-Hyeon;Ahn, Dong-Hwan
    • Korean journal of communication and information
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    • v.57
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    • pp.84-108
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    • 2012
  • This article is concerned with exploring labour market transformation in newspaper industry and thereby looking into skill formation and professionalization of journalists. In Korea, according to previous research, newspaper journalist labour market had been characterized by a low inter-firm mobility of workers and patterns of long-term employment and firm-based skill training. However, over the past few years, as new product strategies of newspaper firms has changed due to management crisis employers pull back from the responsibilities of investment on skill training and securing job stability for journalists. However, in spite of overall weakened firm-based skill formation systems within the market, there still seems to be long way to build alternative systems of skill developments for them. As a result, it will be argued that, in the absence of manifest labor market institutions such as apprenticeships or skill certification system, which are assumed to traditionally certify workers' professionalization, occupational identity and professionality of newspaper journalist labour market will be weakened. Labor market data from interviews with journalists in the newspaper industry are used in order to test this hypothesis.

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Effect of Sputtering Powers on Mg and Ga Co-Doped ZnO Thin Films with Transparent Conducting Characteristics (RF 마그네트론 스퍼터를 이용하여 제작한 MGZO 박막의 구조적 및 전기적, 광학적 특성에 미치는 스퍼터링 전력의 영향)

  • Kim, In Young;Shin, Seung Wook;Kim, Min Sung;Yun, Jae Ho;Heo, Gi Seok;Jeong, Chae Hwan;Moon, Jong-Ha;Lee, Jeong Yong;Kim, Jin Hyoek
    • Korean Journal of Materials Research
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    • v.23 no.3
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    • pp.155-160
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    • 2013
  • ZnO thin films co-doped with Mg and Ga (MxGyZzO, x + y + z = 1, x = 0.05, y = 0.02 and z = 0.93) were prepared on glass substrates by RF magnetron sputtering with different sputtering powers ranging from 100W to 200W at a substrate temperature of $350^{\circ}C$. The effects of the sputtering power on the structural, morphological, electrical, and optical properties of MGZO thin films were investigated. The X-ray diffraction patterns showed that all the MGZO thin films were grown as a hexagonal wurtzite phase with the preferred orientation on the c-axis without secondary phases such as MgO, $Ga_2O_3$, or $ZnGa_2O_4$. The intensity of the diffraction peak from the (0002) plane of the MGZO thin films was enhanced as the sputtering power increased. The (0002) peak positions of the MGZO thin films was shifted toward, a high diffraction angle as the sputtering power increased. Cross-sectional field emission scanning electron microscopy images of the MGZO thin films showed that all of these films had a columnar structure and their thickness increased with an increase in the sputtering power. MGZO thin film deposited at the sputtering power of 200W showed the best electrical characteristics in terms of the carrier concentration ($4.71{\times}10^{20}cm^{-3}$), charge carrier mobility ($10.2cm^2V^{-1}s^{-1}$) and a minimum resistivity ($1.3{\times}10^{-3}{\Omega}cm$). A UV-visible spectroscopy assessment showed that the MGZO thin films had high transmittance of more than 80 % in the visible region and that the absorption edges of MGZO thin films were very sharp and shifted toward the higher wavelength side, from 270 nm to 340 nm, with an increase in the sputtering power. The band-gap energy of MGZO thin films was widened from 3.74 eV to 3.92 eV with the change in the sputtering power.

Radiotherapy Results of Stage I Glottic Cancer (조기 성문암의 방사선 치료 결과)

  • Kim, Jae-Chul;Park, In-Kyu
    • Radiation Oncology Journal
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    • v.16 no.3
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    • pp.245-250
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    • 1998
  • Purpose : This study was to evaluate survival, failure patterns, and prognostic factors of stage I squamous cell carcinoma of the glottic larynx after curative radiation therapy. Materials and Methods : A retrospective analysis was done for 57 patients with glottic cancer who were treated with curative radiation therapy from June 1985 to November 1992. There were 55 male and two female patients. Patients' age ranged from 17 to 71 years(median 39 years). Radiation therapy was delivered five times a week, 2 Gy daily, total 66 Gy using 6 MV X-ray. Results : Complete response(CR) was noted in 51 out of 57 patients (89.5%) and persistent disease (PER) in six out of 57 patients(10.5%). The disease-free survival rates at 3 and 5 years were 72.9% and 63.8%, respectively. Seven failures were observed among 51 CR patients during follow-up. Salvage total laryngectomy for six recurred patients and partial laryngectomy for one recurred patient were done with successful results, i.e., all of them were actually salvaged. Among six PER patients, salvage total laryngectomy for two patients and partial laryngectomy for two patients were done and two patients refused operation. Following salvage surgery for the four PER patients, three were salvaged and one failed locoregionally. Among the 13 failures 10(76.9%) were salvaged with surgery. The ultimate local control rate at 5 years was 92.3% and overall 47 out of 57 (82.5%) patients were able to preserve their larynx. The 5-year disease-free survival rates were 85.5% for posterior lesions, and 61.6% for anterior lesions(P<0.05). Cord mobility, involvement of anterior commissure, field size, and T stage did not impact on disease-free survival. Conclusion : Considering the high percentage of voice preservation with initial radiotherapy, radiotherapy should be the first choice in the treatment of stage 1 glottic carcinoma.

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A Pedestrian Network Assignment Model Considering Space Syntax (공간구문론(Space Syntax)을 고려한 통합보행네트워크 통행배정모형)

  • Lee, Mee Young;Kim, Jong Hyung;Kim, Eun Jung
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.14 no.6
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    • pp.37-49
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    • 2015
  • In Space Syntax, the greater the degree of integration between separate links, the greater the links' accessibility from the target network. As such, planning pedestrian walks so that links with high degrees of integration are connected, or else inducing high integration value land use are both valid options. The travel distribution model reflects how walking demand, or more specifically, the pedestrian, partakes in route choosing behavior that minimizes select criteria, notably level of discomfort, as measured using travel distance and time. The model thus demonstrates travel patterns associated with demand pertaining to minimization of discomfort experienced by the pedestrian. This research introduces a method that integrates Space Syntax and the pedestrian travel distribution model. The integrated model will determine whether regions with high degrees of integration are actually being used as pivots for pedestrian demand movement, as well as to explain whether the degree of integration is sustained at an appropriate level while considering actual movement demand. As a means to develop the integrated model, a method that combines display of the visibility of the space syntax network and road-divided links is proposed. The pedestrian travel distribution model also includes an alternative path finding mechanism between origin and destination, which allows for uniform allocation of demand.

Study on $CuInTe_2$ Single Crystals Growth and Characteristics(I) ($CuInTe_2$ 단결정 성장과 특성연구(I))

  • 유상하;홍광준
    • Korean Journal of Crystallography
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    • v.7 no.1
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    • pp.44-56
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    • 1996
  • CuInTe2 synthesised in a horizontal electric furnace was found to be polycrystalline. Single crystals of CuInTe2 were grown with the vertical Bridgman technique. The structure, Hall effect of the crystals were measured in the temperature range 30 to 293K. Both the polycrystals and single crystals of CuInTe2 were tetragonal in structure. The lattice constants of the polycrytals were measured as a=6.168Å and c=12.499Å, with c/a=2.026, these of the single crystals were measured as a=6.186Å and c=12.453Å, with c/a=2.013. The growth plane of the oriented single crystals was confirmed to be a (112) plane from the back-reflection Laue patterns. The Hall effect of the CuInTe2 single crystals was measured with the method of van der Pauw The Hall data of the samples measured at room temperature showed a carrier concentration of 2.14×1023holes/m3, a conductivity of 739.58Ω-1m-1, and a mobility of 2.16×10 -2m 2/V·s for the sample perpendicular to the c-axis. Values of 1.51×1023holes/m3, 717.55Ω-1m-1, and 2.97×10-2 m2/V·s were obtained for the sample parallel to the c-axis. The Hall coefficients for the samples both perpendicular and parallel to the c-axis in the temperature range 30K to 293K were always positive values. Thus the CuInTe2 single crystal was determined to be a p-type semiconductor.

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The Effect of Thermal Annealing and Growth of $CuGaSe_2$ Single Crystal Thin Film for Solar Cell Application (태양전지용 $CuGaSe_2$ 단결정 박막 성장과 열처리 효과)

  • Hong, Kwang-Joon;You, Sang-Ha
    • Journal of the Korean Solar Energy Society
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    • v.23 no.2
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    • pp.59-70
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    • 2003
  • A stoichiometric mixture of evaporating materials for $CuGaSe_2$ single crystal thin films was prepared from horizontal electric furnace. Using extrapolation method of X-ray diffraction patterns for the polycrystal $CuGaSe_2$, it was found tetragonal structure whose lattice constant $a_0$ and $c_0$ were $5.615{\AA}$ and $11.025{\AA}$, respectively. To obtain the single crystal thin films, $CuGaSe_2$ mixed crystal was deposited on thoroughly etched semi-insulating GaAs(100) substrate by the hot wall epitaxy (HWE) system. The source and substrate temperatures were $610^{\circ}C$ and $450^{\circ}C$, respectively. The crystalline structure of the single crystal thin films was investigated by the photoluminescence and double crystal X-ray diffraction (DCXD). The carrier density and mobility of $CuGaSe_2$ single crystal thin films measured with Hall effect by van der Pauw method are $5.01\times10^{17}cm^{-3}$ and $245cm^2/V{\cdot}s$ at 293K. respectively. The temperature dependence of the energy band gap of the $CuGaSe_2$ obtained from the absorption spectra was well described by the Varshni's relation, $E_g$(T)=1.7998 eV-($8.7489\times10^{-4}$ eV/K)$T^2$/(T+335K). After the as-grown $CuGaSe_2$ single crystal thin films was annealed in Cu-, Se-, and Ga-atmospheres, the origin of point defects of $CuGaSe_2$ single crystal thin films has been investigated by the photoluminescence(PL) at 10 K. The native defects of $V_{CU},\;V_{Se},\;Cu_{int}$ and $Se_{int}$ obtained by PL measurements were classified as a donors or acceptors type. And we concluded that the heat-treatment in the Cu-atmosphere converted $CuGaSe_2$ single crystal thin films to an optical n-type. Also, we confirmed that Ga in $CuGaSe_2$/GaAs did not form the native defects because Ga in $CuGaSe_2$ single crystal thin films existed in the form of stable bonds.

Comparative Studies of Digestive Fluid Protein of Silkworm Bombyx mori, Larvae reared on Mulberry Leaves and Artificial Diets (상엽육잠과 인공사료육잠의 소화액단백질의 비교연구 - 소화액 RFP를 중심으로 -)

  • 박희정;문재유
    • Journal of Sericultural and Entomological Science
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    • v.28 no.1
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    • pp.15-23
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    • 1986
  • This study has been carried out to acquire some basic informations on the digestive fluid of Silkworm, Bombyx mori for developing artficial diets. Silkworms reared on mulberry leaves and artificial diet, were used in this experiments. The results obtained are as follows ; 1. The Red Fluorescent protein was precipitated in 50% acetone solution and did not dissolved in n-butanol solution, but dissolved in methanol solution. 2. Electrophoretic analysis results of mulberry leaves rearing B. mori and artificial diet rearing B. mori, which has been treated with 50% acetone solution were as follows. i) There was distinct difference at the position of high mobility ii) Red Fluorescence was observed only at the position of first band of mulberry leaves rearing B. mori. iii) No different was shown in the electrophoretic patterns of mulberry leaves rearing B. mori on 5th instar 1st-3rd day, but some difference on 5th instar 4th, 5th day. 3. The RFP is the basic protein which has PI 8-9 according to the isoelectric electrophhoresis. 4. The SDS-polyacrylamide gel electrophoresis analysis showed that the molecular weight of RFP was 27,000. 5. The Sephadex G-75 chromatographic analysis showed that there was three peaks between number 16 and 28 in the mulberry leaves rearing B. mori chromatogram, but two peaks between number 18 and 31 in the artifical diet rearing B. mori chromatogram.

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Dental Consultations and Treatment Pattern of Pediatric Inpatient in Severance Hospital (세브란스 병원에 입원한 환자들의 소아치과 협진의뢰 내용 및 진료현황)

  • Song, Jihyeo;Lee, Koeun;Song, Je Seon;Kim, Seong-Oh;Lee, Jaeho;Choi, Hyung-jun
    • Journal of the korean academy of Pediatric Dentistry
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    • v.46 no.2
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    • pp.200-208
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    • 2019
  • The purpose of this study was to analyze the dental consultation of pediatric inpatients to the department of pediatric dentistry in Yonsei University Severance Hospital, and to investigate the change in patterns. In 2017, 268 pediatric patients (384 cases) admitted to the Severance Hospital were referred to the department of pediatric dentistry. The mean age was 6.6 years, and most of the patients were referred from the Department of Pediatric Hematology Oncology and Rehabilitation Medicine. The chief complaints were as follows: oral examination (31%), dental caries (20%), oral pain (10%), tooth mobility (10%), pre-operative evaluation (9%) and others (20%). 41% of the patients received only oral examination without treatment. Dental caries were the most frequent dental diagnosis of the patients. 28% (111 cases) of patients received operative treatments, 22 cases were treated under general anesthesia. Oral health is closely related to systemic diseases, especially for hospitalized patients. Dental consultations should be encouraged for prevention and early appropriate treatments. For this purpose, it is necessary to establish a referral system and perform dental treatment under general anesthesia.

Characteristics of Intra and Inter-Regional Population Mobility Resulting from Innovative City Development (혁신도시 건설에 따른 권역내·외 인구이동 특성)

  • Seong-Won KANG;Tae-Heon MOON;Hye-Lim KIM
    • Journal of the Korean Association of Geographic Information Studies
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    • v.26 no.4
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    • pp.1-16
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    • 2023
  • In 2005, the selection of 10 innovation cities was completed, and since 2013, public institutions began relocating to innovation cities. As a policy aimed at promoting balanced regional development, there were significant expectations from the regions. However, although the population moving to innovation cities has increased, it remains to be seen how much inflow is from the capital region and what spatial characteristics exist nationwide. Therefore, this study aims to analyze whether the innovation cities are fulfilling their roles by examining the patterns of inflow from the capital region and the spatial characteristics, and to reassess the policy direction for future innovation cities. We utilized the Microdata Integrated Service (MDIS) provided by Statistics Korea from 2013 to 2021. For the data collection reasons, we focused on analyzing the three cities. The results showed that in the initial stages of innovation city development, there was a significant influx of population from the capital region, leading to some effects on population dispersion and balanced regional development. However, over time, a phenomenon emerged where more people started to move back to the capital region, indicating a problematic trend. Furthermore, the Gyeongbuk Innovation City and Gwangju-Jeonnam Innovation City showed similarities in terms of reasons for migration, age of householder, and number of household members. However, the Gyeongnam Innovation City exhibited distinct characteristics compared to the other two cities. While the reasons for this phenomenon may be diverse, the current situation suggests that the goal of achieving "balanced national development" has reached its limits. Therefore, urgent measures need to be taken for improvement that take regional characteristics into account. Furthermore, in designing the second phase of the public institution relocation plan is required to avoid repeating the same issues and ensure a more thoughtful approach.

Analysis and Exposure Assessment of Factors That Affect the Concentration of Ambient PM2.5 in Seoul Based on Population Movement (인구 유동에 따른 서울시 대기 중 초미세먼지 농도 변화 요인 분석 및 노출평가)

  • Jaemin Woo;Jihun Shin;Gihong Min;Dongjun Kim;Kyunghwa Sung;Mansu Cho;Byunglyul Woo;Wonho Yang
    • Journal of Environmental Health Sciences
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    • v.50 no.1
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    • pp.6-15
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    • 2024
  • Background: People's activities have been restricted due to the COVID-19 pandemic. These changes in activity patterns may lead to a decrease in fine particulate matter (PM2.5) concentrations. Additionally, the level of population exposure to PM2.5 may be changed. Objectives: This study aimed to analyze the impact of population movement and meteorological factors on the distribution of PM2.5 concentrations before and after the outbreak of COVID-19. Methods: The study area was Guro-gu in Seoul. The research period was selected as January to March 2020, a period of significant population movement changes caused by COVID-19. The evaluation of the dynamic population was conducted by calculating the absolute difference in population numbers between consecutive hours and comparing them to determine the daily average. Ambient PM2.5 concentrations were estimated for each grid using ordinary kriging in Python. For the population exposure assessment, the population-weighted average concentration was calculated by determining the indoor to outdoor population for each grid and applying the indoor to outdoor ratio to the ambient PM2.5 concentration. To assess the factors influencing changes in the ambient PM2.5 concentration, a statistical analysis was conducted, incorporating population mobility and meteorological factors. Results: Through statistical analysis, the correlation between ambient PM2.5 concentration and population movement was positive on both weekends and weekdays (r=0.71, r=0.266). The results confirmed that most of the relationships were positive, suggesting that a decrease in human activity can lead to a decrease in PM2.5 concentrations. In addition, when population-weighted concentration averages were calculated and the exposure level of the population group was compared before and after the COVID-19 outbreak, the proportion of people exceeding the air quality standard decreased by approximately 15.5%. Conclusions: Human activities can impact ambient concentrations of PM2.5, potentially altering the levels of PM2.5 exposure in the population.