자율주행에 관한 관심은 전 세계적으로 증가하고 있으며, 글로벌 자동차 제조사들과 기술기업들이 자율주행 분야에 대한 투자를 늘 리고 있어 향후 자동차 산업과 교통체계 전반에 큰 변화가 전망된다. 이처럼 자율주행 관련 연구와 개발은 끊임없이 진보하고 있으며, 관련 연구 수행은 계속해서 이루어질 것으로 보인다. 연구 수행에 있어 동향 파악은 필수 요소이며, 본 연구에서는 국내 자율주행 연 구 동향을 분석하고자 한다. 연구 동향을 분석한 다양한 분야의 선행연구 검토 결과, 각각 연구 목적에 맞는 다양한 데이터베이스를 이용하여 데이터를 수집하였으며 연구 주제어 혹은 초록을 분석데이터로 활용하였음을 확인하였다. 자율주행 연구 동향에 대해 분석 한 선행연구 검토 결과, 기존 연구들은 분야를 구분하지 않고 연구를 수집·분석하였음을 확인하였다. 자율주행은 도로, 교통, 자동차, 기계, 컴퓨터, 전자, 전기 등 다양한 분야를 포함하고 있기에 분야별 연구 동향 분석이 필요하다. 이에 본 연구에서는 도로·교통 분야 의 동향 분석을 위해 최근 5년간(2019년~2023년) 국내 도로·교통 분야 등재 학술지에 게재된 학술 논문을 대상으로 연구 동향을 분석 하였으며, 보다 많은 텍스트 데이터를 활용하기 위해 주제어가 아닌 초록을 활용하였다. 키워드 출현 빈도 분석을 통해 주요 키워드를 도출하였으며, 토픽 모델링을 통해 주요 연구주제를 도출하였다. 본 연구에서 수행한 자율주행 연구 동향 파악은 도로·교통 분야에서 향후 수행될 자율주행 연구 방향 수립에 시사점을 제공할 것이라 기대된다.

In the contemporary era, 3D printing technology has become widely utilized across diverse fields, including biomedicine, industrial design, manufacturing, food processing, aerospace, and construction engineering. The inherent advantages of automation, precision, and speed associated with 3D printing have progressively led to its incorporation into road engineering. Asphalt, a temperature-responsive material that softens at high temperatures and solidifies as it cools, presents distinctive challenges and opportunities in this context. For the effective implementation of 3D printing technology in road engineering, 3D printed asphalt (3DPA) must exhibit favorable performance and printability. This requires attributes such as good fluidity, extrudability, and buildability. Furthermore, materials utilizing 3DPA for crack repair should possess high viscosity, elasticity, toughness, superior high-temperature stability, and resistance to low-temperature cracking. These characteristics ultimately contribute to enhancing pavement longevity and ensuring worker safety.

이 글은 한국어 학습을 위한 웹 기반 한자 사전 모델을 제시하기 위한 것이다. 중국 문화권 학습자를 대상으로 한 이 연구에서는 웹 기반 한자 사전의 필요성을 확인하고 기존 사전의 한자 단어 학습의 문제점 을 분석하였다. 한자 단어 학습 시 한자 원어 형태소 인식이 중요하다고 보고 이를 반영한 별도의 팝오버 (popover) 창을 개발하였다. 한자 사전의 미시구조에는 항목, 단어 유형, 발음, 한-베트남어 단어(있는 경우), 한자의 어원, 한-베 소리(voice)가 포함되며, 이밖에 베트남어 어원에 대한 설명, 한자의 원래 형태소 와 관련된 한-베 단어, 번역, 설명, 예시 등이 포함되어야 함을 밝혔다. 그런 다음, 한자어 형태소와 한자- 베트남어의 발음을 포함하는 어원 틀, 베트남어 및 한자어의 한자 형태소 의미를 포함한 웹 사전을 구성하 고 그 활용 방안을 보여주었다. 본 연구는 한자어 형태소와 관련된 베트남 단어에 대한 정보를 추가하고, 프로그래밍 기술, 데이터베이스 업데이트 과정, 300개 규모의 한자 사전 모델을 제시한 기초연구로써 이후 한국어 학습자를 위한 웹 한자 사전 구축에 보탬이 되고자 한다.

Al2O3 has excellent sintering properties and is important in semiconductor manufacturing processes that require high-temperature resistance and chemical inertness in a plasma environment. In this study, a comprehensive analysis of the chemical characteristics, physical properties, crystal structure, and dispersion stability of three commercially available Al2O3 powders was conducted. The aim was to provide a technological foundation for selecting and utilizing appropriate Al2O3 powders in practical applications. All powders exhibited α-Al2O3 as the main phase, with the presence of beta-phase Na2O-11Al2O3 as the secondary phase. The highest Na+ ion leaching was observed in the aqueous slurry state due to the presence of the secondary phase. Although the average particle size difference among the three powders was not significant, distinct differences in particle size distribution were observed. ALG-1SH showed a broad particle size distribution, P162 exhibited a bimodal distribution, and AES-11 displayed a uniform unimodal distribution. Highconcentration Al2O3 slurries showed differences in viscosity due to ion release when no dispersant was added, affecting the electrical double-layer thickness. Polycarboxylate was found to effectively enhance the dispersion stability of all three powders. In the dispersion stability analysis, ALG-1SH exhibited the slowest sedimentation tendency, as evidenced by the low TSI value, while P162 showed faster precipitation, influenced by the particle size distribution.

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.

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).

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.

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.

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.

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)

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.

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.