• 한국안전학회지
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• 제36권2호
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• pp.58-67
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• 2021

Incident investigation is regarded as a means to improve safety performance. For the prevention of industrial accidents, measures such as providing safety education, enhancing management interest and participation, establishing a safety management system, and conducting inspection of the work site are necessary. In particular, accident investigation activities, which are an important element of safety management, help to prevent similar accidents, thereby minimizing damage and enhancing work safety. They are critical for understanding business-related incidents and the vulnerabilities and opportunities associated with them. Therefore, it is clear that accident investigation activities are important for accident prevention. The primary focus of many incident investigation processes is on identifying the cause of an event. While considerable research has been conducted on potential accident investigation tools there has been little research on including the views and experiences of practitioners in the accident investigation process. In this study, a questionnaire survey was conducted among safety managers in the domestic manufacturing/construction industry to understand the practice of accident investigation. The investigation pertained to companies' accident investigation systems, the competence of investigators, and the identification and recommendations of the cause of accidents. From the analysis results of accident investigations, investigators' competence, the difficulty level of investigations, and the root causes of accidents were identified from the viewpoint of the participants of the accident investigations. In particular, the development of standardized and simple accident investigation methods and their dissemination to companies were found to be necessary for activating the root cause of accidents. Based on this, it can be used as basic data for the development of root cause analysis investigation techniques that are easily applicable to organizations.

• Genomics & Informatics
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• 제20권2호
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• pp.19.1-19.15
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• 2022

Alfalfa (Medicago sativa) is an important food and feed crop which rich in mineral sources. The WUSCHEL-related homeobox (WOX) gene family plays important roles in plant development and identification of putative gene families, their structure, and potential functions is a primary step for not only understanding the genetic mechanisms behind various biological process but also for genetic improvement. A variety of computational tools, including MAFFT, HMMER, hidden Markov models, Pfam, SMART, MEGA, ProtTest, BLASTn, and BRAD, among others, were used. We identified 34 MsWOX genes based on a systematic analysis of the alfalfa plant genome spread in eight chromosomes. This is an expansion of the gene family which we attribute to observed chromosomal duplications. Sequence alignment analysis revealed 61 conserved proteins containing a homeodomain. Phylogenetic study sung reveal five evolutionary clades with 15 motif distributions. Gene structure analysis reveals various exon, intron, and untranslated structures which are consistent in genes from similar clades. Functional analysis prediction of promoter regions reveals various transcription binding sites containing key growth, development, and stress-responsive transcription factor families such as MYB, ERF, AP2, and NAC which are spread across the genes. Most of the genes are predicted to be in the nucleus. Also, there are duplication events in some genes which explain the expansion of the family. The present research provides a clue on the potential roles of MsWOX family genes that will be useful for further understanding their functional roles in alfalfa plants.

• 한국수학교육학회지시리즈C:초등수학교육
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• 제25권4호
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• pp.395-410
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• 2022

명사화는 문법적 은유 중 하나로, 동적 표현을 명사 상당 어구를 통해 표현하는 것이다. 수학 문장제에서 명사화를 사용한 문장 표현은 수학화 단계에서 주목해야 할 대상을 분명하게 한다는 장점과 일상적 표현과 달리 문장의 이해를 어렵게 하고 온전한 수학적 모델링 단계의 경험을 저해한다는 단점을 모두 지닌다. 본 연구의 목적은 수학 학습시 학생들의 어려움을 야기하는 문장제 해결과 관련하여, 언어학적 요소인 명사화의 관점에서 교과서 문장제를 분석하고 시사점을 도출하는 것이다. 이를 위해 2015 개정 교육과정에 따른 초등학교 수학 교과서의 수와 연산 영역에 포함된 연산 관련 문장제 341개의 명사화 유형을 학년군별, 차시 활동과 단원 평가, 특화 차시별, 수식화에 대한 명시적인 요구 문장제의 네 가지 관점에서 분석하였다. 분석 결과에 기초하여 수학 문장제의 언어적 표현과 관련한 교수학적 시사점을 도출하였다.

• Journal of Preventive Medicine and Public Health
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• 제55권6호
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• pp.539-548
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• 2022

Objectives: The purpose of this study was to assess the organizational effectiveness of the introduction of a healthcare information system (electronic medical records and databases) in healthcare in Kazakhstan. Methods: The authors used a combination of 2 methods: expert assessment and strengths, weaknesses, opportunities, and threats (SWOT) analysis. SWOT analysis is a necessary element of research, constituting a mandatory preliminary stage both when drawing up strategic plans and for taking corrective measures in the future. The expert survey was conducted using 2 questionnaires. Results: The study involved 40 experts drawn from specialists in primary healthcare in Aktobe: 15 representatives of administrative and managerial personnel (chief doctors and their deputies, heads of medical statistics offices, organizational and methodological offices, and internal audit services) and 25 general practitioners. Conclusions: The following functional indicators of the medical and organizational effectiveness of the introduction of information systems in polyclinics were highlighted: first, improvement of administrative control, followed in descending order by registration and movement of medical documentation, statistical reporting and process results, and the cost of employees' working time. There has been no reduction in financial costs, namely in terms of the costs of copying, delivery of information in paper form, technical equipment, and paper.

• 농업과학연구
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• 제49권4호
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• pp.657-666
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• 2022

Nitrogen (N) is a vital element in growing crops and is essential for improving the yield and quality of crops. Thus, N fertilizer is the most widely used fertilizer and the primary N input source in soil-crop systems. Inorganic fertilizers such as urea are known to improve crop productivity and increase soil fertility. However, application with excessive amounts can interfere with crop growth and accelerate soil acidification. For these reasons, the use of organic fertilizers, which mainly contain organic nitrogen, has gradually increased worldwide. Therefore, this study evaluated the effects of N fertilizer on the growth of Chinese cabbage including its functional compounds glucosinolates (GSLs). For the cultivation of Chinse cabbage, inorganic fertilizer was used for urea, and organic fertilizers were divided into conventional and biochar-based fertilizers. The growth parameters of Chinese cabbage treated by organic fertilizers was better than those of the inorganic fertilizers. Additionally, it was found that their co-application was more efficient. However, their GSL contents were lower with the application of the organic fertilizers. The characteristics of the experimental soil also changed according to the type, amounts and co-application of fertilizers. Therefore, this study presents the basis for an eco-friendly method that can increase the functionality and productivity of Chinese cabbage compared to conventional cultivations.

• 한국지반공학회논문집
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• 제39권11호
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• pp.23-31
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• 2023

콘크리트 궤도의 침하는 고속열차의 안전한 운행을 크게 저해할 수 있으며 복구에 상당한 비용이 소요되므로 최근 큰 문제로 대두되고 있다. 침하의 가장 큰 원인 중 하나는 터널공사의 부산물로 발생하는 암석재료를 적정한 입도분를 가진 토사 혼합 없이 하부노반 성토에 사용하기 때문으로 보고되고 있다. 본 논문에서는 암석재료로 성토된 하부노반의 부분 보강으로 인한 침하억제 효과를 수치해석으로 평가하였다. 하부노반에 일정하게 배치된 기둥 형태의 보강 영역은 상부노반에 지반아칭을 유발하게 되며 성토하중이 보강된 영역에 집중하게 되어 침하가 억제되는 효과가 있다. 유한요소해석을 통하여 보강된 영역의 크기, 강성, 간격이 하부노반의 침하억제에 미치는 효과를 평가하였으며, 해석 결과를 토대로 침하를 허용치 이내로 억제하기 위한 최소 보강 간격을 결정하는 설계 방법을 제안하였다.

• Advances in aircraft and spacecraft science
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• 제10권3호
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• pp.223-243
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• 2023

There is a burgeoning demand for minimizing the mass of satellites because of its direct impact on reducing launch-to-orbit cost. This must be done without compromising the structure's efficiency. The present paper introduces a relatively low-cost and easily implementable approach for optimizing structural mass to a maximum natural frequency. The natural frequencies of the satellite are of utmost pertinence to the application requirements, as the sensitive electronic instrumentation and onboard computers should not be affected by the vibrations of the satellite structure. This methodology is applied to a realistic model of Al-Azhar University micro-satellite in partnership with the Egyptian Space Agency. The procedure used in structural design can be summarized in two steps. The first step is to select the most favorable primary structural configuration among several different candidate variants. The nominated variant is selected as the one scoring maximum relative dynamic stiffness. The second step is to use perforation patterns reduce the overall mass of structural elements in the selected variant without changing the weight. The results of the presented procedure demonstrate that the mass reduction percentage was found to be 39% when compared to the unperforated configuration that had the same plate thickness. The findings of this study challenge the commonly accepted notion that isogrid perforations are the most effective means of achieving the goal of reducing mass while maintaining stiffness. Rather, the study highlights the potential benefits of exploring a wider range of perforation unit cells during the design process. The study revealed that rectangular perforation patterns had the lowest efficiency in terms of modal stiffness, while triangular patterns resulted in the highest efficiency. These results suggest that there may be significant gains to be made by considering a broader range of perforation shapes and configurations in the design of lightweight structures.

• Geomechanics and Engineering
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• 제36권4호
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• pp.355-366
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• 2024

The original elastoplastic Hardening Soil model is formulated actually partly under hexagonal pyramidal Mohr-Coulomb failure criterion, and can be only used in specific stress paths. It must be completely generalized under Mohr-Coulomb criterion before its usage in engineering practice. A set of generalized constitutive equations under this criterion, including shear and volumetric yield surfaces and hardening laws, is proposed for Hardening Soil model in principal stress space. On the other hand, a Mohr-Coulumb type yield surface in principal stress space comprises six corners and an apex that make singularity for the normal integration approach of constitutive equations. With respect to the isotropic nature of the material, a technique for processing these singularities by means of Koiter's rule, along with a transforming approach between both stress spaces for both stress tensor and consistent stiffness matrix based on spectral decomposition method, is introduced to provide such an approach for developing generalized Hardening Soil model in finite element analysis code ABAQUS. The implemented model is verified in comparison with the results after the original simulations of oedometer and triaxial tests by means of this model, for volumetric and shear hardenings respectively. Results from the simulation of oedometer test show similar shape of primary loading curve to the original one, while maximum vertical strain is a little overestimated for about 0.5% probably due to the selection of relationships for cap parameters. In simulation of triaxial test, the stress-strain and dilation curves are both in very good agreement with the original curves as well as test data.

• Design & Manufacturing
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• 제18권2호
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• pp.17-22
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• 2024

Lightweight of plastic containers is becoming an important issue due to increasing environmental legislation and consumer awareness. In this study, the CAE analysis was conducted to optimize the shape of a 500 ml lightweight square polyethylene terephthalate(PET) bottle. First, the linear buckling alaysis using the finite element method was performed to analyze the correlation between the primary geometric parameters of the bottle and the buckling critical load. Then, the optimal geometry parameters were derived, and the actual buckling load was predicted by non-linear buckling simulation. The validity of the simulation results was verified by top-loading tests of PET bottles molded with the optimized geometry. The elastic modulus and tensile yield strength of PET through tensile tests were measured to improve the accuracy of the simulation. As a result of the tensile tests, the modulus of elasticity of PET increased from 2,900 MPa to 4,275 MPa, and the tensile yield strength increased from 52.4 MPa to 88.1 MPa. Finally the buckling load of the optimized PET bottle was found to be approximately 236 N, which is very similar to the simulation precition of 238 N. This study shows the feasibility and accuracy of the CAE analysis approach for the lightweight design of PET bottles, and will provide useful guidelines for the design of PET bottles.

• 한국전통조경학회지
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• 제32권1호
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• pp.63-73
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• 2014

본 연구는 조선시대의 대표적 별서정원인 소쇄원을 사례로 전통 공간에서 나타나는 기호 및 기표로서의 상징적 색채발현 분석 및 그 의미 해석을 통해 작정 의도와 색채와의 관련성 분석을 목적으로 수행하였다. 전통 색채 및 소쇄원의 작정배경 등에 대해서는 관련 문헌연구를 통해 수행하였으며, 실증적 분석 대상으로서의 내용은 소쇄원도와 소쇄원 48영 시문에서 나타나는 경관 및 공간 요소 그리고 음양오행사상(陰陽五行思想)에 근거한 오정색과 관련한 작시의 내용을 대상으로 하였다. 특히, 소쇄원에서 나타나는 공간적 요소를 크게 시각적, 공감각적, 상징 인식적 공간 요소로 구분하여 시각적 공간으로 공간 및 경물의 위치와 방위, 공감각적 공간으로 계절과 시간 및 오관, 상징 인식적 공간으로 칠정과 사단 등으로 구분하고 각각의 공간요소에 대해 오정색 체계 분석을 통해 작정 의도와 공간 의미의 상관성 여부를 분석하는 방법을 통해 연구를 진행하였다. 소쇄원의 3개 공간 구성을 기준으로 색채를 분석한 결과, 모두 74개의 오정색 항목이 도출되었다. 첫째, 시각적 공간 구성요소에서는 청색 2회, 적색 1회, 황색 6회, 백색 4회, 흑색 5회 등 모두 18회의 오정색 요소가 나타났다. 이 분석 결과에서 자연과 생명을 상징하는 청색과 적색보다도 만물의 근본을 상징하는 황색과 깨끗함과 순결을 상징하는 백색이 상대적으로 높게 나타난 것은 양산보의 소쇄원 작정 의도가 자연을 즐기는 데 우선을 두기보다는 오히려 정의롭지 못한 세상에 대한 작정자의 순결한 의지를 상징하기 위한 의미와 연결되어 있는 것으로 해석될 수 있었다. 둘째, 소쇄원 48영에서 주로 추출된 공감각적 공간 구성 요소에서는 청색 11회, 적색 8회, 황색 4회, 백색 5회, 흑색 10회 등 38회의 오정색 요소가 나타났다. 여기서는 자연과 생명을 상징하는 청색과 적색이 세상의 근본과 순결 그리고 지식을 상징하는 황색과 흑색보다 높게 나타남으로써 비록 작정자의 세상에 대한 순결성을 지키고자한 의지로 공간을 작정하였지만, 별서정원에서 자연 즐김과 지식 탐구에 대한 감정을 누리려는 별서 고유의 기본적 기능에 충실하고 있음을 의미하고 있는 것으로 해석되었다. 마지막으로 역시 48영에서 주로 추출된 상징 인식적 공간 요소에 대한 오정색은 청색 4회, 적색 5회, 백색 9회 등 18회가 나타나는 것으로 분석되었다. 이 색채 분석 결과에서는 정치적 순결을 상징하는 백색이 자연과 생명을 상징하는 청색과 적색과 같은 빈도로 출현하고 있음으로써 소쇄원의 작정 의도가 시를 통해 정치적 순결성 강조와 자연 즐김을 동일한 비중으로 감정적으로 드러내고 있는 것으로 해석되었다. 특히, 이 3종류의 분석에서 공감각적 공간 구성요소에 대한 오정색의 빈도가 38회로 약 51%로 가장 높게 나타나고, 시각적 공간 구성 요소와 인지 상징적 공간 구성 요소가 각각 18회로 각 24.5%의 빈도 분포를 보이고 있다. 이러한 현상은 양산보의 소쇄원 작정 의도는 전체적으로 보면, 정의롭지 못한 세상에 대한 작정자의 순결성을 지키고자 함과 함께 별서정원의 기본인 자연과 자연의 생명력을 즐기려는 의도가 같은 비중으로 숨어있음을 상징하고 있다고 해석을 될 수 있었다. 본 연구는 소쇄원 작정의 상징적 의미와 공간 구성 요소와의 상관성을 음양오행설(陰陽五行說)에 근거한 오정색을 기준으로 분석함으로써 전통 별서정원에서 숨어있는 전통 색채를 밝히고자 하였지만, 이러한 이론이 다른 별서정원에서도 일반적으로 적용될 수 있을 것인지를 탐색하는 것은 소쇄원과는 다른, 순수한 자연 즐기기나 강학, 기능 등 뚜렷한 작정 의도가 숨어 있는 다른 사례의 별서정원에 대한 연구를 통해 밝혀질 수 있을 것으로 사료된다.