검색결과

검색조건
좁혀보기
검색필터
결과 내 재검색

간행물

    분야

      발행연도

      -

        검색결과 910

        21.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The public safety management guidelines were introduced in 2019 and continue to be dedicated to advancing comprehensive measures for public safety management, with a primary focus on prioritizing the safety and well-being of the public within governmental institutions. To achieve this goal, our previous study developed a establishment procedure of risk assessment-based safety inspection system for public institutions that order construction projects and applied it to highway construction projects to evaluate its effectiveness. To enhance the practicality of the establishment procedure, it is essential to collect and analyze feedback from stakeholders regarding its performance and suitability. This study conducted a survey involving 200 participants who had experience with the establishment procedure, and performed statistical analyses to evaluate its performance and applicability. The survey results indicated that the participants reported a high level of satisfaction (scoring 4 and above on a 5-point Likert scale) in several areas: specialization of safety inspection items for different types of work (with a satisfaction rate of 65%), the evaluation process for safety ratings (64.5%), and their willingness to recommend the procedure to other institutions (75.5%). In the factor analysis with Varimax rotation, two factors emerged: (1) a specialization factor related to safety inspection items, and (2) a grading factor associated with safety evaluation results. Regression analyses of these factors unveiled significant positive relationships with improvements in safety and health performance, including the prevention of fatal accidents, heightened safety responsibility, and raised safety inspection standards. The establishment procedure of safety inspection system developed in our previous study can play a crucial role in reducing accidents resulting in fatalities and injuries at construction sites, ultimately contributing to a safer working environment for all involved parties.
        4,000원
        22.
        2023.11 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        The effects of La3+ substitution for Sr2+-site on the crystal structure and the dielectric properties of (Ba0.7Sr0.3-3x/2Lax) (Ti0.9Zr0.1)O3 (BSLTZ) (0.005 ≤ x ≤ 0.02) ceramics were investigated. The structural characteristics of the BSLTZ ceramics were quantitatively evaluated using the Rietveld refinement method from X-ray diffraction (XRD) data. For the specimens sintered at 1,550 °C for 6 h, a single phase with a perovskite structure and homogeneous microstructure were observed for the entire range of compositions. With increasing La3+ substitution (x), the unit cell volume decreased because the ionic size of La3+ (1.36 Å) ions is smaller than that of Sr2+ (1.44 Å) ions. With increasing La3+ substitution (x), the tetragonal phase fraction increased due to the A-site cation size mismatch effect. Dielectric constant (εr) increased with the La3+ substitution (x) due to the increase in tetragonality (c/a) and the average B-site bond valence of the ABO3 perovskite. The BSLTZ ceramics showed a higher dielectric loss due to the smaller grain size than that of (Ba0.7Sr0.3)(Ti0.9Zr0.1)O3 ceramics. BSLTZ (x = 0.02) ceramics met the X7R specification proposed by the Electronic Industries Association (EIA).
        4,000원
        23.
        2023.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        PURPOSES : The purpose of this study is to derive dropout rates according to various international roughness index (IRI) specifications using ProVAL, develop a comparative methodology, and indirectly assess the level of road management in each country. METHODS : Based on a literature review, the IRI specifications for each country were collected, and the ProVAL analysis tool was used to compare and analyze dropout rates according to each specification. Thus, the dropout rate rankings for each country were calculated. Additionally, by analyzing the correlation between dropout rates according to each threshold, a model was created to convert the threshold between the most commonly used baseline distances of 100 m and 161 m. RESULTS : Dropout rates were derived according to the standards of each country and rankings were assigned. Comparing 51 standards, the IRI level of New Mexico appeared to be the highest, whereas the domestic specifications ranked 36th. A model was created to convert the threshold between the standard distances of 100 m and 161 m. CONCLUSIONS : This study objectively assessed the roughness standards in various countries using the dropout rate and IRI ranking specifications. The highest specification was found for the asphalt of New Mexico in the USA, with the domestic specification ranking 36th. A model that converts the thresholds between the most commonly used baseline distances of 100 m and 161 m was developed, with slight differences across sections. For a precise conversion, individual models may be required for each section.
        4,000원
        30.
        2023.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study was conducted to evaluate Korean rice cultivars to search any suitable varieties for the northern region of the Korean Peninsula (North Korea). A total of 92 rice varieties which included 74 bred cultivars from South Korea, 13 collections from North Korea and five local cultivars from China, were involved in the evaluating trials for their performance. Stability at three sites inthe northeastern areas of China, which are located in the northern border areas of North Korea, for three years from 2017 to 2019. The ecologically well-adapted rice varieties were selected at each trial site during the first year and employed again as the materials for the subsequent yield trials. A total of six varieties with relatively better performing and stability were selected through the subsequent trials at three sites for three years: Unkwang, Daejin and Taebaek at Dandong region; Hanseol and Taebong at Longjin region; Taebong and Namweon at Hunchun region, respectively. Dandong is located in the southeast parts of Liaoning, which has similar climatic characteristics to the west coastalregion of North Korea. Longjin is located in the middle-east parts of Jilin, which has also similar climatic characteristics to the northern inland region of North Korea. Hunchun is located in the northeastern parts of Jilin, which has presumably similar climatic characteristics to the northern part of the eastern coastal region of North Korea. Unkwang is characterized by its early maturity, with the heading at the 2nd of August, and reveals a yield potential of 7.11 T/ha with resistance to the blast (BL) and the bacterial leaf blade (BLB) diseases. It is predicted to be suitable for the northern area of the Suyang mountain region and the central inland region of North Korea. Daejin has asemi-early maturity heading around the 6th of August and yields of 6.06 T/ha with resistance to BL, BLB, and stripe virus (SV) diseases. Daejin will be adaptable to the northern area of Suyang mountain region. Taebaek is medium maturing variety of Indica/Japonica type. It is heading at the 14thof August with good ripening at maturity, and has yield potential of 6.84 T/ha with resistance to BL, BLB and SV diseases. It will be adaptable to the southern area of Suyang mountain region. Hanseol is early maturing, heading on the 3rd of August, and yields 6.44 T/ha with the short stature and cold tolerance (CT). It will be adaptable to the northern inland and mountainous regions of North Korea. Taebong is semi-early maturingwith the heading at the 6th of August and has a yield potential of 6.96 T/ha with cold tolerane and blast resistance. Taebong was also outstanding in theHunchun region, indicating a more or less wide adaptability in cold areas. It is expected to be adaptable to the northern inland region of North Korea as well as the northern part of the eastern coastal region. Namweon is a medium-maturing variety with aheading date of August 10, and a yield potential of 4.76 T/ha with cold tolerance and resistance to rice neck blast disease. It is expected to be adaptable to the northern part of the eastern coastal region.
        4,500원
        31.
        2023.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Public institutions have a responsibility to ensure the safety of their employees and the public. One way to do this is to implement a systematic safety inspection system based on risk assessments and continuous improvements. This study developed a systematic safety inspection system for public institutions that are ordered construction projects. The proposed system in this study consists of a three-step process: (1) developing safety grade evaluation tables, (2) preparing and conducting safety inspections, and (3) evaluating and improving safety management grades. The first step is to develop safety grade evaluation tables by analysis and diagnosis of the construction site's work type, disaster statistics, and related laws. The second step is to conduct safety inspections using the developed evaluation tables. The third step is to determine the safety management grade based on the results of the safety inspection, and to improve risk factors found during the safety evaluation. The proposed system was implemented in highway construction projects carried out by public institutions. The results showed that the proposed system has two major effects: (1) reducing accident-related deaths and injuries, (2) improving safety management levels by continuous evaluation and improvement. The proposed system can be utilized in construction projects ordered by public institutions to improve the level of occupational safety and health.
        4,000원
        32.
        2023.08 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        The effects of Ni2+ substitution for Mg2+-sites on the microwave dielectric properties of (Mg1-xNix)(Ti0.95(Mg1/3 Ta2/3)0.05)O3 (0.01 ≤ x ≤ 0.05) (MNTMT) ceramics were investigated. MNTMT ceramics were prepared by conventional solid-state reaction. When the MgO / TiO2 ratio was changed from 1.00 to 1.02, MgTi2O5 was detected as a secondary phase along with the MgTiO3 main phase in the MNTMT specimens sintered at 1,400 °C for 4h. For the MNTMT specimens with MgO / TiO2 = 1.07 sintered at 1,400 °C for 4h, a single phase of MgTiO3 with an ilmenite structure was obtained from the entire range of compositions. The relative density of all the specimens sintered at 1,400 °C for 4h was higher than 95 %. The quality factor (Qf) of the sintered specimens depended strongly on the degree of covalency of the specimens, and the sintered specimens with x = 0.01 showed the maximum Qf value of 489,400 GHz. The dielectric constant (K) decreased with increasing Ni2+ content because Ni2+ had a lower dielectric polarizability (1.23Å3) than Mg2+ (1.32Å3). As Ni2+ content increased, the temperature coefficient of resonant frequency (TCF) improved, from -55.56 to -21.85 ppm/°C, due to the increase in tolerance factor (t) and the lower dielectric constant (K)
        4,000원
        33.
        2023.07 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        Porous ceramics are used in various industrial applications based on their physical properties, including isolation, storage, and thermal barrier properties. However, traditional manufacturing environments require additional steps to control artificial pores and limit deformities, because they rely on limited molding methods. To overcome this drawback, many studies have recently focused on fabricating porous structures using additive manufacturing techniques. In particular, the binder jet technology enables high porosity and various types of designs, and avoids the limitations of existing manufacturing processes. In this study, we investigated process optimization for manufacturing porous ceramic filters using the binder jet technology. In binder jet technology, the flowability of the powder used as the base material is an important factor, as well as compatibility with the binder in the process and for the final print. Flow agents and secondary binders were used to optimize the flowability and compatibility of the powders. In addition, the effects of the amount of added glass frit, and changes in sintering temperature on the microstructure, porosity and mechanical properties of the final printed product were investigated.
        4,000원
        34.
        2023.06 구독 인증기관 무료, 개인회원 유료
        농촌진흥청에서 진행한 ‘왕귀뚜라미 돌보기 프로그램’으로 노인들의 우울증과 인지 기 능 개선을 통한 정서적 안정에 도움이 된다는 사실을 과학적인 방법을 통해 확인하고 이 를 관련 저명 학술지 제기하였다. 이를 바탕으로 본 연구는 전라북도 익산시에 거주하는 5세부터 10세까지 아동 50명을 대상으로 직접 만나 전문가의 자문을 받아 작성한 총 11 문항의 설문지를 활용하여 조사를 진행하였다. 설문조사는 소리 곤충에 대한 인식도는 높 았지만, 선호도와 사육 의향에서 부정적인 결과가 나왔다. 또한 소리곤충 중 귀뚜라미의 소리에 대한 문항에서는 긍정적인 결과가 나온 반면 여치의 소리에 대한 문항에서는 부정 적인 결과가 나왔다. 본 논문에서는 소리 곤충에 대한 아동의 인식도 및 선호도를 파악하 기 위한 설문조사 연구를 통해 관련 연구와 활동에 자료를 제공하고자 한다.
        4,000원
        35.
        2023.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Patients with oral squamous cell carcinoma (OSCC) generally have an elevated expression of homeobox C6 (HOXC6) gene. We found that HOXC6 was the significantly upregulated gene in hypopharyngeal squamous cell carcinoma (FaDu) cells using RNA-seq analysis. However, it remains unclear whether HOXC6 plays a role in tumor process mechanism. Our study aimed to explore the potential oncogenic role and the detailed molecular mechanism of HOXC6 in FaDu cells. In this study, Sirt1 was validated to be overexpressed in FaDu cells and associated with HOXC6 expression. Overexpression of HOXC6 promoted the cell colony formation, whereas inhibition of Sirt1 by Sirt1 inhibitor EX527 reduced cell proliferation/colony formation and migration, and induced apoptosis in HOXC6 overexpressed FaDu cells. Interestingly, mechanistic study showed that EX527 mediated Sirt1 suppression led to decreased HOXC6 expression and upregulation of Sirt1 significantly increased the expression of HOXC6. HOXC6 was shown to cooperate with Sirt1 to enhance cell survival. We propose that HOXC6 promotes cell growth/colony formation, and that the HOXC6 may be a progression of hypopharyngeal carcinoma by activating Sirt1 pathways.
        4,300원
        36.
        2023.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        성경에 나오는 소위 ‘갈릴리 호수의 일화’를 여러 시인들이 썼다. 정지용은 「갈릴레아 바다」를 썼고, 윤동주가 이 일을 배경으로 「이적」을 쓰고, 박목월은 「갈릴리 바다의 물빛을」을 쓴다. 이 글을 통해 정지용과 윤동주는 모두 치열한 자아성찰을 소재로 ‘갈릴리 일화’를 인유하고 있다는 사실을 확인할 수 있었다. 정지용에게 갈릴리 일화가 자아를 성찰하는 소재로 쓰였다면, 윤동주에게는 갈 릴리 일화가 실존주의적 참여를 다짐하는 소재로 쓰이고 있는 시를 확인했다. 정지용과 윤동주가 종교시를 쓰기에 이르는 종교적 배경에 대해서도 살펴보았 다. 다만 정지용의 신앙시를 보면 관념적이고, 윤동주의 신앙시를 보면 적극적인 의지가 강하게 보인다. 시는 그렇지만 정지용 또한 친일시를 쓰지 않고 친일행 위를 거부하는 현실적인 저항을 했다. 이 글은 정지용의 「갈릴레아 바다」와 윤 동주의 「이적」을 비교했지만 많은 아쉬움이 남는다. 특히 정지용의 종교시는 한 편 한 편 따로 해석하는 것을 넘어, 정지용 시집 4부에 실린 순서대로, 「불사 조」부터 시작하여 이후에 실리는 8편의 시 「나무」, 「은혜」, 「별」, 「임종」, 「갈 릴레아 바다」, 「그의 반」, 「다른한울」, 「또 하나 다른 태양」을 통해, 정지용이 무엇을 얘기하려 했는지 그 흐름을 보아야 할 것이다. 아쉬움은 있지만 이 글을 통해 두 시인이 서양의 종교인 기독교를 어떻게 한국 시로 융합하여 창작했는 지, 두 가지 대표적인 표정을 확인할 수 있다면 다행이겠다.
        6,600원
        39.
        2023.04 KCI 등재 구독 인증기관 무료, 개인회원 유료
        PURPOSES : The main purpose of this study is to identify directions for improvement of triangular islands installation warrants through analysis of the characteristics of crashes and severity with and without triangular islands on intersections. METHODS : The data was collected by referring to the literature and analyzed using statistical analysis tools. First, an independence test analyzed whether statistically significant differences existed between crashes depending on the installation of triangular islands. As a result of the analysis, individual prediction models were developed for cases with significant differences. In addition, each crash factor was derived by comparison with each model. RESULTS : Significant differences appeared in the "crash frequency of serious or fatal" and "crash severity" owing to the installation of triangular islands. As a result of comparing crash factors through the individual models, it was derived that the differences were dependent on the installation of the triangular islands. CONCLUSIONS : As a result of reviewing previous studies, it is found that improving the installation warrants of triangular islands is reasonable. Through this study, the need to consider the volume and composition ratio of right-turn vehicles when installing a triangular island was also derived; these results also need to be referred to when improving the triangular island installation warrants.
        4,000원
        1 2 3 4 5