북한 핵에 대한 IAEA의 사찰이 2002년 종료된 이후 북한은 2017년에 여섯 번째의 핵실험과 ICBM급인 화성-15형을 시험 발사하고 핵무력을 완성하였다고 선언하였다. 그리고 북한은 2021년 초 조선노동당 8차 대 회에서는 핵고도화 선언을 하기도 하였으며 2022년 들어 극초음속미사 일, IRBM, ICMB 등을 시험발사하며 한반도 정세를 더욱 악화시키고 있 다. 시간이 경과할수록 북한의 핵능력은 더욱 확장되고 고도화할 가능성 이 많다. 한국과 미국을 포함하는 국제사회는 북한과의 비핵화 협상을 적극 추진하고 실질적 검증을 통해 북한의 완전한 비핵화를 달성해야 한다. 본 연구의 목적은 군비통제 검증 분야의 역사적 성공 사례인 INF 조약 이행과정 분석을 통하여 북한 핵에 대한 핵심적 검증과정인 현장사찰을 촉진하는 방안을 모색하는 것이다. 북한의 완전한 비핵화를 위한 협상에 서 가장 고비가 될 수 있는 검증의 현장사찰에 관한 실행가능하고 발전 적인 방안은 다음과 같다. 첫째, 북한을 NPT에 복귀시키고 IAEA의 안전 조치협정에 가입하도록 하여 ‘IAEA 주도의 현장사찰’을 실시하여야 한 다. 둘째, 북한 핵시설 중 미신고·미공개된 핵시설에 대한 ‘선택적이고 효과적인 현장사찰’이 이루어져야 한다. 셋째, 북한의 폐쇄적인 사회적 특수성을 고려하여 ‘상호협력적 현장사찰’이 이루어져야 한다. 넷째, 다 양한 국내 및 국제기술수단을 이용하여 원격 감시, 위성 및 항공 감시, 핵관련 인원의 인터뷰, 문헌조사, 시료 채취 및 정밀분석 등을 시행하는 ‘과학기술 집약적 통합 현장사찰’이 이루어져야 한다.

PURPOSES : Abroad, road pavement materials vary depending on the speed and traffic volume of vehicles, but owing to the negative perception of block pavements, sidewalks, parking lots, and parks are primarily used in Korea. In addition, since speed restriction policies such as safety speed 5030 have been implemented recently, it is necessary to use block pavements for roadways, which are considered to have the effect of reducing speed. Therefore, it is necessary not only to actively discuss the introduction of block pavements for roadways but to continue research on the effectiveness of the performance evaluation and to change the perception of roads in Korea. METHODS : In this study, five indicators (surface damage, surface temperature, driving speed of vehicle, noise, and suspended dust) were selected for a sustainable road environment. The performance evaluation index of block pavement for roadways was decided according to the domestic and international literature, and the data were collected based on the evaluation index in the section with block pavement for roadways in Korea. RESULTS : The damage rate was calculated 0.35% according to the breakage of block and Maintenance Control Index(MCI) was ranked A~B even though the pavement was used for more than 4~5 years. The surface temperature of block pavement has a temperature reduction effect of 7 ℃ compared with ordinary asphalt pavement and a speed reduction of approximately 4 km/h on average; therefore, the traffic calming effect of block pavements can be expected. The noise of block pavement and asphalt pavement exhibited a similar level, and the noise level experienced by pedestrians did not change significantly as a result of frequency analysis. The measurement of road suspended dust around the road confirmed the possibility of reducing the concentration of road dust in the air owing to the smooth surface drainage and the results indicated the possibility. CONCLUSIONS : The results of this study are expected to contribute to the recognition and functional improvement of domestic block pavements by continuous monitoring to ensure the reliability of blocks. In addition, it is necessary to ensure the reliability of the quality and functional evaluation of paving materials through continuous on-site monitoring.

With the advancement of industrialization, modern industry had sophisticated technology, and manufacturers also demanded high-precision measurement accuracy. Improving the quality level by increasing the reliability of measurement results as well as accurate measurement is a key issue to increase the competitiveness of today's manufacturing industry. In general, measurement results depend on tolerances in the industrial field, and it may be difficult to guarantee the reliability of the data in the case of an industry that deals with precision parts. Currently, measurement uncertainty is mainly applied to the calibration and test fields of instruments. This study is aim to apply measurement uncertainty as a way to improve the accurate analysis and reliability of measurement results in the industrial field. For this, precision parts connected by shaft and hole were selected among geometric elements, and roundness and cylindricity were measured using a roundness measuring instrument and CMM. And, taking into account the environment in which these measurements were made, factors affecting the measurement results were derived, and a mathematical model was established to calculate the measurement uncertainty. Applying uncertainty in the field in this way is expected to improve the level of quality and accurate analysis of measurement results.

PURPOSES : The purpose of this study is to preliminarily examine the field applicability of modular pavement marking tape (PMT) to increase the lane awareness of motorists on existing roadways. METHODS : A pavement marking tape (PMT) comprises an adhesion layer and a paint coating layer. The adhesion layer is prepared using gussasphalt-based materials that have properties similar to those of existing asphalt materials. Thermal adhesion is performed to adhere the tape to the pavement. For the paint coating layer, polyurea materials are selected after reviewing the existing materials suitable for pavement lane marking. To conduct field evaluations on the adhesion layer, monitoring is performed after the pilot deployment of the PMT is completed. Twelve samples are prepared to investigate the optimal ratios for the mixture of paint coating layer materials. The durability of the PMT is examined using a turntable road-marking test system (RPA) with a wheel load on the samples. A total of 50,000 RPA, equivalent to P4, is performed. The performance is evaluated by capturing the retroreflectivity measure, which is used as an indicator of the pavement marking performance. The PMT is utilized on a roadway segment with significant heavy vehicle traffic, and continuous monitoring is performed to examine its performance in the field. RESULTS : Based on a visual inspection of the adhesion layer material, no significant issue is observed in terms of the adhesion performance of the PMT. Furthermore, the overall retroreflectivity obtained from the RPA exceeds 300 mcd/m2·lux. It is discovered that the optimal ratios for the mixture of polyurea and binder for the paint coating layer are 4:6 and 2:8, respectively, which results in a retroreflectivity that is 90% or above the initial retroreflectivity. Using a prototype of the PMT for field tests, a performance evaluation is conducted by analyzing the retroreflectivity measured after 2 and 7 weeks from the prototype deployment. The retroreflectivity measured for the first 2 weeks after the deployment appears acceptable for field use. However, the retroreflectivity is reduced significantly when it is measured 7 weeks after deployment, resulting in the necessity for a more reliable material that can retain long-term durability. CONCLUSIONS : The lane awareness of a motorist is crucial for accident mitigation under not only nighttime driving, but also severe weather conditions. In this regard, modular PMT is expected to increase the lane awareness of motorists, thereby improving the quality of lane marking materials. In this study, various exploratory field tests are conducted to analyze the field applicability of the PMT. It is noteworthy that the results presented herein are obtained from preliminary performance evaluations of the PMT. Hence, further investigations pertaining to the long-term durability of PMTs must be conducted using advanced test equipment such as an accelerated pavement tester.

Recently, virtual reality (VR) and augmented reality (AR) technologies are attracting attention as core technologies in the era of the 4th industrial revolution. These virtual and augmented reality technologies are being used in a variety of industries, including the construction industry, healthcare industry, and manufacturing industry, to innovate in communication and collaboration, education and simulation, customer service and reinvention of the customer experience. In this paper, VR-based experiential safety education was conducted for workers of shipbuilding companies in Ulsan city, and for them, the educational effectiveness such as immersion, site applicability, safety accident prevention, education satisfaction, overall performance, and safety behavior in VR-based safety experience education were measured. In addition, we examined whether the immersion of VR-based safety experience education affects site applicability, safety accident prevention, educational satisfaction, overall performance, and safety behavior. Furthermore, it was analyzed whether site applicability plays a mediating role in the relationship between immersion and safety accident prevention. As a result, it was found that the immersion of VR-based safety experience education affects site applicability, safety accident prevention effect, education satisfaction, overall performance, and safety behavior, and that site applicability mediates between immersion and safety accident prevention. Based on these results, we suggests a direction for the development of VR-based contents in the field of safety and health and the transformation of safety and health education in the future.

본 연구에서는 활성탄소를 이용하여 해양환경으로 유출된 침강 HNS를 현장에서 대응하기 위한 기술 개발을 목적으로, 활용 가능한 활성탄소의 조건을 검토하고 예상 소요량을 산출하였다. 입자 크기별 7종의 활성탄소들을 대상으로 침강 속도를 측정하였고, 침강 HNS로 분류된 클로로포름(CHCl3)에 대한 흡착용량을 실험실 규모 실험(lab-scale test)으로 측정하였다. 또한 7종 활성탄소들에 대하여 유해 물질함량과 용출 실험을 실시하여 용출된 유해물질 함량을 정량 분석하였다. 평균 침강속도(Mean particle-settling velocity)는 0.5~8 cm/sec의 범위로 8-20 mesh 경우를 제외하고 입자의 크기가 클수록 침강속도가 빨랐으며, 클로로포름에 대한 흡착효율은 대체로 입자가 작을수록 표면적이 넓어져 증가되었다. 또한 현장 투입 후 2차 오염가능성 확인을 위한 유해물질함량과 용출 실험 실험에서 >100 mesh의 활성탄소는 전함량분석결과가 아연(Zn)과 비소(As)가 수처리제기준보다 높고, 용출실험결과에서도 크롬(Cr), 아연(Zn), 비소(As)가 다른 활성탄소에 비해 높은 농도로 용출되었다. 흡착효율, 침강속도, 유해성분 용출량 등을 종합적으로 고려하여 현장 처리 적용 가능한 활성탄소는 20-60, 20-40, 2mm&down mesh 이었으며, 흡착용량을 최우선으로 판단하여 투입물량을 계산하면 최소 현장 투입 물량은 각각 0.82, 0.90, 1.28 ton/㎘ 이다.

PURPOSES : This study primarily aims to develop and evaluate a Smart Station - a novel underground pipeline measure system - to overcome the challenges of conventional surveying methods. METHODS : This study built two prototypes of the Smart Station. By reflecting issues revealed through the field tests of the first prototype, this study produced the second Smart Station prototype. The organization of the hardware units in the second prototype was reconfigured to maximize its usability for operators in the field. Furthermore, by developing the ‘Digital Twin X’, an integrated Smart Station management software suite, the second prototype was capable of 1) producing a digital workbook for field operators, 2) managing underground pipeline information, and 3) displaying 3-dimensional maps in and around an underground pipeline. The applicability of the second prototype was examined through three field tests conducted in one open space location, where no urban valley effects were expected, and two locations in a downtown area, with urban valley effects. Given the actual field installation of underground pipelines, this study collected data via both conventional surveying methods and the Smart Station to evaluate the performance of the Smart Station. Analyzing the field data, this study examined the data collection time and position accuracy of an underground pipeline measured by the Smart Station. RESULTS : The field test results revealed that both the conventional surveying method and the Smart Station produced similar performances in data collection time and measurement accuracy in the open space test location. However, in the case of downtown locations affected by urban valley effects, the Smart Station achieved 100 % measurement accuracy while the conventional surveying method achieved 93 % accuracy. It was also observed during the field test that no data were collected due to the constraints of the work schedule and various field conditions (e.g., weather and/or traffic congestion). The data collection times at the open space locations were 10 s for both the conventional surveying method and the Smart Station. However, the data collection times at the downtown locations appeared to be 10 s and 360 s by the Smart Station and the conventional surveying methods, respectively, thereby proving that the Smart Station outperforms the conventional method in its measurement efficiency. CONCLUSIONS : It is envisioned that the Smart Station produces higher work efficiency for field operators as it enables them to collect high accuracy data in a timely and quick manner and not only build a database for the collected data but also vividly visualize it in the field. In the future, it is necessary to conduct additional field tests under various conditions for the in-depth investigation of a Smart Station. In addition, it is expected that the Smart Station will be enhanced by coupling augmented reality (AR) technologies.

The fourth industrial revolution encourages manufacturing industry to pursue a new paradigm shift to meet customers' diverse demands by managing the production process efficiently. However, it is not easy to manage efficiently a variety of tasks of all the processes including materials management, production management, process control, sales management, and inventory management. Especially, to set up an efficient production schedule and maintain appropriate inventory is crucial for tailored response to customers' needs. This paper deals with the optimized inventory policy in a steel company that produces granule products under supply contracts of three targeted on-time delivery rates. For efficient inventory management, products are classified into three groups A, B and C, and three differentiated production cycles and safety factors are assumed for the targeted on-time delivery rates of the groups. To derive the optimized inventory policy, we experimented eight cases of combined safety stock and data analysis methods in terms of key performance metrics such as mean inventory level and sold-out rate. Through simulation experiments based on real data we find that the proposed optimized inventory policy reduces inventory level by about 9%, and increases surplus production capacity rate, which is usually used for the production of products in Group C, from 43.4% to 46.3%, compared with the existing inventory policy.