This study analyzed the emission characteristics of major air pollutants (dust, nitrogen oxides, hydrogen chloride, and carbon monoxide) emitted from domestic public waste incineration facilities based on their operating elements. Using automatic measuring equipment for smokestacks (TMS), data was collected from 97 facilities from 2015 to 2023. The emission source unit (kg/ton) was evaluated based on the facility’s capacity, aging level, and incineration type. Emissions were calculated, and descriptive statistical analysis was performed based on the mean, standard deviation, and coefficient of variation. As a result of the analysis, it was found that the larger the facility capacity, the lower the average emission and volatility, which suggests that the operational stability of large facilities is high. On the other hand, facilities that had deteriorated for 10 to 15 years had the highest emission rates, and emissions decreased in facilities that were aged more than 20 years. In addition, the pyrolysis and high-temperature melting incineration facilities had lower NOx and HCl emissions than the conventional incineration type. Furthermore, CO showed the greatest volatility overall, which was found to be particularly difficult to manage in facilities in the early to mid stages of aging. These results provide empirical evidence that the structural characteristics and incineration type of incineration facilities have a significant impact on air pollutant emissions and can serve as useful basic data for policy-making, including for implementing region-wide initiatives and planning major repairs in the future.
This study aimed to categorize grammar items in English textbooks used across Korean elementary, middle, and high schools by specific grade levels. To achieve this, we developed an automated grammar item analyzer using natural language processing techniques, which analyzed 52,964 sentences from the textbooks. We selected 173 grammar items from the 2022 revised national curriculum and classified them according to the methodology used to determine CEFR levels in the English Grammar Profile. The classification results are as follows: 18 items for Grade 3 of elementary school, 6 for Grade 4, 11 for Grade 5, 8 for Grade 6, 29 for the first year of middle school, 43 for the second year, 22 for the third year, 29 for the first year of high school, and 7 for the second year. Based on these findings, this study discusses pedagogical implications, focusing on practical applications such as refining assessment tools, more precisely defining curricular objectives, and developing grade-specific instructional materials.
마비성 패류독소 중독증(paralytic shellfish poisoning; PSP)은 삭시톡신과 그 유사체로 오염된 패류를 섭취했을 때 발생하며, 저림, 구토 등의 증상에서부터 근육 마비와 심각한 경우 호흡 마비로 이어져 사망에 이를 수 있다. 독 성등가계수(toxic equivalency factors; TEFs)는 다양한 마 비성 패류독소의 독성을 표준화하여 위험성을 평가하는 데 사용된다. 마비성 패류독소를 검출하기 위해 사용되던 마우스 생체 실험(mouse bioassay; MBA)에 대한 윤리적 문제가 제기되면서 고성능액체크로마토그래피와 같은 기 기 분석법으로의 전환이 시도되고 있지만, 유사체들의 적절 한 TEF를 설정하기 위해서는 여전히 동물 모델을 통한 생 체 내 독성 데이터가 필수적이다. 본 연구에서는 동물 수를 줄이면서도 신뢰할 수 있는 경구투여 독성 결과를 얻기 위 해 삼단계 반응표면-경로 (three-level RSP) 설계를 사용했다. 인증 표준 물질을 이용하여 각 독소의 초기 용량과 조정 계 수를 결정하고 시험을 진행했으며, STX.2HCl, NeoSTX, dcSTX, GTX1&4, GTX2&3, dcGTX2&3의 반수치사량 (및 TEF) 값은 각각 451.3 (1.00), 306.5 (1.47), 860.9 (0.52), 644.5 (0.70), 915.3 (0.49), 2409.3 (0.19)로 나타났다. 도출된 TEF 값은 2016년 WHO에서 권고한 TEF 값뿐만아니라, 이 전에 보고된 경구 투여 반수치사량을 기반으로 한 TEF 값 과 강한 상관관계를 보였다. 본 연구는 마비성 패류독소 뿐 만 아니라 신규 미관리 해양생물독소에 대해 적절한 TEF를 설정하는 데 있어 삼단계 반응표면경로 설계를 윤리적 우 려와 신뢰할 수 있는 독성 데이터의 필요성 사이에서 효과 적으로 균형을 맞출 수 있는 방법으로 제안한다.
In this study, we proposed a novel concept of liquid level indicator that can stably measure the liquid level even with changes in liquid density by enormous temperature changes. This uses a distributed optical fiber sensor based on Rayleigh scattering with high spatial resolution. Additionally, taking advantage of the flexibility of an optical fiber sensor, we introduced a bendable supporting structure and made it possible to freely adjust the angle for ease of installation of the liquid level indicator. In the proof-of-concept experiment using a prototype incorporating the proposed concept, we confirmed that the interface location can be effectively detected by utilizing the difference in heat transfer characteristics between liquid and gas phases, demonstrating the feasibility of liquid level measurement. Such a liquid level indicator is expected to enable more accurate level measurements in environments with huge temperature changes and to be conveniently used even in situations where installation and maintenance of the level meter are challenging due to complex internal structures.
Maintaining sea superiority through successful mission accomplishments of warships is being proved to be an important factor of winning a war, as in the Ukraine-Russia war. in order to ensure the ability of a warship to perform its duties, the survivability of the warship must be strengthened. In particular, among the survivability factors, vulnerability is closely related to a damage assessment, and these vulnerability data are used as basic data to measure the mission capability. The warship's mission capability is usually measured using a wargame model, but only the operational effects of a macroscopic view are measured with a theater level resolution. In order to analyze the effectiveness and efficiency of a weapon system in the context of advanced weapon systems and equipments, a warship's mission capability must be measured at the engagement level resolution. To this end, not the relationship between the displacement tonnage and the weight of warheads applied in the theater level model, but an engagement level resolution vulnerability assessment method that can specify physical and functional damage at the hit position should be applied. This study proposes a method of measuring a warship’s mission capability by applying the warship vulnerability assessment method to the naval engagement level analysis model. The result can be used as basic data in developing engagement algorithms for effective and efficient operation tactics to be implemented from a single unit weapon system to multiple warships.
This study was conducted to investigate whether there were differences in eco-friendly food, home meal replacement (HMR) purchases, and eating-out behavior according to the level of agri-food consumer competence. The data for the study were extracted from main food consumers (n=3,321) in the 2022 Food Consumption Behavior Survey. The competence index was divided into awareness-attitude-practice items, and three groups were classified by competence level. The results showed an agri-food consumer competency score of 70.62, with the highest score for awareness (73.96), followed by practice (69.28) and attitude (66.18). The frequency of purchasing eco-friendly food was higher in the excellent group compared to other groups, and quality and price satisfaction was higher with higher competency (p<0.001). Regarding HMR, the results showed that the shortage group had the lowest HMR consumption rate, and satisfaction decreased as competence decreased (p<0.001). The main reason for eating-out was to enjoy food in all groups (59.0%), followed by a lack of cooking time in the excellent group (15.7%) and hassle with food preparation in the moderate and shortage groups (17.3%, 16.6%) (p<0.001). In short, agri-food consumption competency showed differences by contents and components, and differences in food purchases and eating-out behavior by competency level were found.
Adsorption of arsenic by graphene-based adsorbents is widely applied to remove arsenic from water and has become a promising technology. However, most of the reported studies were conducted at a relatively higher concentration of arsenic in As (V) oxidative form, whereas the As (III) is more difficult to remove from water and more toxic, which prompted us to conduct the study at a lower concentration of 1 ppm in As (III). A Facile and controlled synthesis of graphene-based metal/ metal oxide nanomaterials and adsorptive removal of aqueous As (III) is reported here. Adsorbents were characterized using spectroscopy (FTIR, XPS and Raman) and microscopy (TEM). The maximum uptake of arsenic obtained was 88.8% from the RGO-Fe3O4 composite among all the adsorbents. The pseudo-second-order model and Intra-particle mass transfer diffusion model were applied to determine the adsorption kinetics with varying contact time between the adsorbents and the As (III) in water to interact. Experimental results suggest that the adsorption of As (III) onto the adsorbents was a multi-step process involving external adsorption to the surface followed by diffusion to the interior. A simple spectrophotometric method also was used for the detection and quantification of As (III).
냉매 오충전은 에어컨에서 빈번하게 발생하는 고장 모드 중 하나로, 적정 충전량 대비 부족 및 과충전 모두 냉방 성능의 저하를 유 발하므로 충전된 냉매량을 정확하게 판단하는 것이 중요하다. 본 연구에서는 퍼지 군집화 기법을 통한 정상상태 식별을 통해 냉매 오 충전량을 다중 분류하는 모델을 개발하였다. 정상상태 식별을 위해 에어컨 운전 데이터에 대해 이동 평균 간의 차이를 활용한 퍼지 군 집화 알고리즘을 적용하였으며, IFDR를 통해 기존 연구된 정상상태 판단 기법들과 식별 결과를 비교하였다. 이후, 시스템 내 상관성 을 고려한 mRMR을 이용해 특징을 선택하였으며, 도출된 특징을 이용해 SVM 기반의 다중 분류 모델이 생성되었다. 제안된 방법은 시험 데이터를 통해 만족할 만한 분류 정확도와 강건성을 도출하였다.
In order to determine fragility curves, the limit state of piers for each damage level is suggested in this paper based on the previous test results in Korea, including our test results. In previous studies, the quantitative measures for damage levels of piers have been represented by curvature ductility, lateral drift ratio, or displacement ductility. These measures are transformed to lateral drift ratios of piers for consistency, and the transformed values are compared and verified with our push-over test results for flexural RC piers with a circular cross-section. The test specimens are categorized concerning the number of lap-splices in the plastic hinge region and whether seismic design codes are satisfied or not. Based on the collected test results in Korea, including ours, the lateral drift ratio for each pier damage level is suggested.
The nature of NPD is conducive to SMEs improvising at all stages of the process. This has the potential to create new knowledge, which, if retained and harnessed, can then be applied at higher strategic levels within the firm. This paper examines this phenomenon, through a preliminary qualitative study.
The aim of this study was to identify strain KCOM 1265 isolated from subgingival plaque at the species level by comparing 16S ribosomal RNA gene (16S rDNA) and genome sequences. The whole genome of strain KCOM 1265 was extracted using the phenol–chloroform extraction method. 16S rDNA was amplified using polymerase chain reaction and sequenced using the dideoxy chain termination method. Pairwise genome comparison was performed using average nucleotide identity (ANI) and genome-to-genome distance (GGD) analyses. The data showed that the percent similarity of 16S rDNA sequence of strain KCOM 1265 was 99.6% as compared with those of Fusobacterium polymorphum ATCC 10953T and Fusobacterium hwasookii KCOM 1249T. The ANI values of strain KCOM 1265 with F. polymorphum ATCC 10953T and F. hwasookii KCOM 1249T were 95.8% and 93.0%, respectively. The GGD values of strain KCOM 1265 with F. polymorphum ATCC 10953T and F. hwasookii KCOM 1249T were 63.9% and 49.6%, respectively. These results indicate that strain KCOM 1265 belongs to F. polymorphum.
본고는 교과의 하나인 한문과의 정의・의미・특징을 바탕으로, 교사 차원의 한문 수업 교육목표 및 교육내용 설계에의 시사점을 발견하는 것을 목표로 한다.
이를 위해 먼저 교과 한문과의 정의와 의미를 살펴보고, 이를 바탕으로 교육적 보편성 및 교과적 특수성・맥락의존적・유동적・목적지향적・가치지향적인 특징을 유추하였다.
이를 바탕으로 한문 수업의 교육목표 및 교육내용 설계에의 시사점을 다음과 같이 발견하였다. 첫째, 교육적 보편성과 교과적 특수성을 동시에 고려하여야 한다. 둘째, 학교 교육이라는 구체적 맥락에 존재하는 사회, 학습자의 요구에도 관심을 가져야 한다. 셋째, 기존에 선정된 교육목표 및 교육내용에 대한 검토가 필요하다. 넷째, 핵심 교육목표의 설정이 필요하다. 다섯째, 교육내용에 있어서는 핵심 지식에 대한 구명이 필요하다.
This study examined how teaching and learning activities in primary English textbooks include the components of creativity and character building. Three third and fourth grade level textbooks based on the 2015 revised curriculum were analyzed in order to find the proportions of the components of creativity and character building, and the types of learning activities that embody those components were analyzed by examining the teachers’ guides. The analysis revealed that all of the textbooks examined included diverse components that were intented to increase creativity, among which components stimulating divergent thinking and originality were a high proportion, while convergent thinking and dispositional aspects appeared less frequently. Among character building components, care-forgiveness and responsibility were two of the more popular components, while honesty and moral judgment were few and far between. From these findings, this study suggests that the components of creativity and character building should be more evenly distributed across textbook activities since they should be of equal importance in education.
Purpose: This study investigated the dietary patterns associated with Korean food and the level of proper eating habits according to recognition of the Kimchi cooking method, and aimed to suggest the necessity of dietary education of traditional foods such as Kimchi. Methods: Based on the results of the national dietary survey conducted in 2014 by Ministry of Agriculture, Food and Rural Affairs of Korea, a total of 1200 subjects were classified into two groups, one that knew how to make Kimchi (53.8%) and another that did not (46.2%). Results: The group that knew how to make Kimchi (FG) showed significantly higher scores in knowledge of how to cook most types of Korean foods and traditional fermented foods than the other group (NG). Moreover, FG showed significantly higher scores in regularity in meals and a higher frequency of Korean foods such as rice, Kimchi, and grilled or stewed food, while it showed significantly lower scores in dietary risk factors than NG. In addition, FG showed significantly higher scores in dietary education interest and number of meals with family during the week than NG. Finally, FG had significantly higher scores in the degrees of practice of all eight items related to proper eating habits. Conclusion: Since recognition of Kimchi cooking has a great influence on maintenance of dietary life, dietary education to improve the cooking ability of traditional foods should be further strengthened.
아스팔트 혼합물은 덤프트럭으로 운반․대기 중 단기노화(short-term aging: STA) 되므로 모든 현장혼합물은 STA후 포설된다. 따라서 실험실에서 현장에 포장된 아스팔트 혼합물의 각종 특성을 추정하려면 같은 재료로 반드시 STA 처리 후 공시체를 제조해야한다. 이것이 실험실 혼합물을 STA 처리하는 근본적인 이유이며, 실험실 STA 방법은 현장상태를 최대한 근사하게 모사(simulation) 토록 규정되어져야 한다. 그러나 국내는 물론 외국 기준도 이러한 근본적인 원리를 제대로 준수 하지 못하고 있어 기준에 제시된 대로 STA를 수행해서는 현장에 포장된 아스팔트 혼합물의 특성을 추정할 수 없다. 이를 해결하기 위한 한 가지 방법의 한 방법은 노화량(aging quantity: AQ) 모델링을 통하여 혼합물의 노화도를 추정하는 것이다. 밀입도 혼합물의 AQ 모델은 기존의 연구에 의하여 지수함수 식으로 와 같이 제시되었다. 하지만 SMA 혼합물은 바인더 함량이 높고 섬유제 등이 사용되어 밀입도와 다르므로 본 연구에서는 SMA에 대한 AQ 모델식을 개발하고 이로부터 단기노화 온도와 시간에 따른 노화도를 추정하는 연구를 수행하였다. 그러므로 본 연구의 목적은 SMA 혼합물의 단기노화도를 추정하기 위하여 기 개발된 AQ 모델을 SMA 혼합물에 적용하여 필요한 보정을 통해 SMA 혼합물의 AQ 모델로 노화도를 추정하는 방안을 제시하는 것이다. 노화도는 아스팔트 노화의 척도로는 가장 많이 쓰이는 절대점도(absolute viscosity: AV)를 이용하였으며 SMA 혼합물을 대상으로 하여 SMA 노화도 정립에 필요한 기초자료를 제시코자 한다.