• Title/Summary/Keyword: Deterioration grade

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제5차 및 제6차 교육과정의 중학교 생물교과 내 환경 관련 단원의 비교 분석 (The comparison of environment-related chapters in the biology textbooks of middle school between the 5th and the 6th curriculum)

  • 김윤경;정해문
    • 한국환경교육학회지:환경교육
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    • 제9권1호
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    • pp.90-99
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    • 1996
  • This study focused on the investigation of objects and contents of environment-related chapters which were contained in the biology textbooks of middle school in the 5th curriculum, and in the 6th curriculum. As a result of objects analysis, cognitive domain such as the knowledge and information categories were allocated more than affective domain as skill, value and attitude, and behavior and participation. Compared with the 5th curriculum, the average-pages of environment-related chapters in the 6th curriculum were decreased. Environment-related chapters in the 6th curriculum also dealt negligibly with the real environmental problems in our country. Therefore the importance of the environment-related chapters of biology textbooks in the 6th curriculum was relatively deceased compared with that in the 5th curriculum. In considering the actual low optional rate of environment subject in middle school, it was thought that the reinforcing effect of environmental education can be hardly expected. Rather, the status of environment subject will grow weaker and weaker. Thus, in order to avoid the deterioration effect of its status and solve its problems, it is necessary to up-grade environment subject as obligatory course or needs strong reinforcement of environmental education.

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Rapid Atypical Progression of Neuro-Behçet's Disease Involving Whole Brainstem and Bilateral Thalami

  • Lee, Sang-Kook;Choi, Sung-Jae;Kim, Sang-Dae;Lim, Dong-Jun
    • Journal of Korean Neurosurgical Society
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    • 제50권1호
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    • pp.68-71
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    • 2011
  • We present a case of Neuro-Behçet's disease with an unpredictable clinical course. A 47-year-old man was admitted to the neurosurgery department of our hospital with a mild headache. Three days after admission, his consciousness suddenly decreased and respiratory distress progressed rapidly. A brain MRI revealed that the previously observed abnormal signal had extended markedly to both the thalamic areas and the entire brain stem, and the surrounding brain parenchyma were compressed by cerebral edema. Based on the patient's symptoms of recurrent oral and genital ulcers, skin lesions, and uveitis, a rheumatologist made a diagnosis of Behçet's disease with CNS involvement. The patient was treated with high-dose methylprednisolone with respiratory assistance in the intensive care unit for 9 days and his neurologic symptoms improved remarkably. Neuro-Behçet's disease must be considered in the differential diagnosis in rapidly deteriorated young neurological patients along with a stroke, low-grade glioma, multiple sclerosis, and occlusive venous disease.

장기폭로실험에 의한 철근콘크리트 보수재료공법 시스템의 열화특성 평가에 관한 연구 (A Study on the Evaluation of Deterioration Properties of Reinforced Concrete Applied Repair Material and Method System by Long Term Exposure Experiment)

  • 최형길;신관수;신승봉;나철성;김규용;김무한
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2007년도 춘계학술논문 발표대회
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    • pp.129-132
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    • 2007
  • In this study, for the establishment of the performance evaluation methods of repair material and method for reinforced concrete structure and the quality control standards of durability recovery method, the quantitative exposure data by exposure experiment under the coastal and normal atmosphere environment is accumulated and analyzed. Investigating and evaluating the result of exposure experiment during 54 months of exposure age under the coastal and normal atmosphere environment, Micro crack, swelling and spatting of surface coating material, crack of repair boundary parts and the great potential difference between repair part and non-repair part were somewhat generated. And the result shown that exposure specimen of coastal environment had lower electrode potential than exposure specimen of normal atmosphere environment.

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열열화에에 따른 600V IV의 조성변화에 관한 연구 (A Study on the Composition Variation of 600v IV with Thermal Deterioration)

  • 최충석;류선희;김형래;이경섭
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1999년도 춘계학술대회 논문집
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    • pp.53-56
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    • 1999
  • The weight decreases of the thermal deteriorated IV were rapidly increased at 80$0^{\circ}C$ and over. At the results of the analysis of the metallurgical microscope photographs. the surface of the thermal deteriorated IV at 30$0^{\circ}C$ was mixed with the elongated and original structures of Cu. But the elongated structures could not detected at 90$0^{\circ}C$ and over. The surface structures of SEM were detected a lot of small rounded particles between crystallizations. The EDX spectra of the thermal deteriorated IV at 3$0^{\circ}C$ were uniformly detected CuL, CuK, OK, and CIK, regardless of the scanning length, but the spectra of CIK could not found at 90$0^{\circ}C$. At the DTA curves, the endothermic reactions were occurred at about 25$0^{\circ}C$ to 30$0^{\circ}C$ and 43$0^{\circ}C$, and the exothermic reactions were occurred at about 48$0^{\circ}C$ respectively.

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공동주택 외부 석재마감에 따른 창호주위 누수방지에 관한 연구 (A Study in the Water Leakage Prevention around the Windows with the Stone Materials in the Apartment House)

  • 윤홍중;조태제
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2006년도 추계 학술논문 발표대회 논문집
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    • pp.117-121
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    • 2006
  • This study intends to suggest the effective methods for water leakage prevention around the windows in stone works to up-grade the outdoor public space that has been taken much portion of apartment housing trends. The subjects of the study was selected among the domestic subcontractors of stone works. There are four methods for water leakage prevention around the windows; Firstly, the painting water-proof method after the masonry. Secondly, the urethane water-proof method after galvanizing panels on the gap. Thirdly, the separation method between stone and substructure and the last one is water-proof method that they put some water-proof screen between stone and substructure with the EPDM sheets. According to the analysis of the water-proof effects, constructability and planning, we could approach to conclusion that the most influent items to the water-leakage are the filling material's deformation, the state of oxygenation and deterioration of work skill. Among the water-proof methods in construction the EPDM sheet is most excellent water-proof method to meet the technical conditions. However, we have to apply it to stone works as a water-proof method for the decrease of the leakage defects after standardizing the materials, test and construction skill because there are many work skills according the subcontractors.

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Partial Thickness Rotator Cuff Tears

  • Shin, Sang-Jin;Seo, Myeong-Jae
    • Clinics in Shoulder and Elbow
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    • 제17권2호
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    • pp.91-100
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    • 2014
  • Partial-thickness rotator cuff tear (PTRCT) is not single disease entity but one phase of disease spectrum. Symptoms of PTRCT vary from being asymptomatic to severe pain leading to deterioration in quality of life. Pathogenesis of degenerative PTRCT is multifactorial. Whereas articular sided PTRCT is usually caused by internal causes, both internal and external causes have important role in bursal sided PTRCT. A detailed history, clinical examination and magnetic resonance angiography are used in the diagnosis of PTRCT. Treatment of PTRCT is chosen based on age, demands of patients, causes and depth of tear. In most patients, non-operative treatment should be initiated. Whereas debridement can be done for less than 6 mm of articular sided PTRCT and in less than 3 mm of bursal sided PTRCT, repair techniques should be considered for higher grade PTRCT than that. Although the effect of acromioplasty is not clear, acromioplasty may be performed when the extrinsic causes appear to be the cause of tear. Either transtendon repair technique or repair after tear completion provided satisfactory clinical outcomes in treatment of articular sided PTRCT.

트리포스포러스 변성폴리에스테르 함유 PU 난연도료의 도막물성 (Physical Properties of Synthetic PU Flame-Retardant Coatings Containing Triphosphorus Modified Polyesters)

  • 박홍수;강영구;김지현;함현식;근장현
    • 한국응용과학기술학회지
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    • 제25권2호
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    • pp.151-159
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    • 2008
  • The flame-retardant coatings were prepared by blending the synthesized triphosphorus modified polyester in the previous paper and hexamethylene diisocyanate-trimer and curing it at room temperature. The characterization of the films of the prepared coatings was performed. It was confirmed that no deterioration of physical properties of PU coatings was observed with the increasing phenylphosphonic acid (PPA) contents. Flame retardancy was tested by a $45^{\circ}$ Meckel burner method and LOI method. With the $45^{\circ}$ Meckel burner method, CATBTP-20C and CATBTP-30C that contain 20 wt% and 30 wt% of PPA, flame retarding component, respectively, showed the first grade flame retardancy with $2.8{\sim}3.9\;cm$ of char length ; and, with LOI method, they exhibited a good flame retardancy as a range of $30{\sim}32%$ of combustion values.

Machine learning in concrete's strength prediction

  • Al-Gburi, Saddam N.A.;Akpinar, Pinar;Helwan, Abdulkader
    • Computers and Concrete
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    • 제29권 6호
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    • pp.433-444
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    • 2022
  • Concrete's compressive strength is widely studied in order to understand many qualities and the grade of the concrete mixture. Conventional civil engineering tests involve time and resources consuming laboratory operations which results in the deterioration of concrete samples. Proposing efficient non-destructive models for the prediction of concrete compressive strength will certainly yield advancements in concrete studies. In this study, the efficiency of using radial basis function neural network (RBFNN) which is not common in this field, is studied for the concrete compressive strength prediction. Complementary studies with back propagation neural network (BPNN), which is commonly used in this field, have also been carried out in order to verify the efficiency of RBFNN for compressive strength prediction. A total of 13 input parameters, including novel ones such as cement's and fly ash's compositional information, have been employed in the prediction models with RBFNN and BPNN since all these parameters are known to influence concrete strength. Three different train: test ratios were tested with both models, while different hidden neurons, epochs, and spread values were introduced to determine the optimum parameters for yielding the best prediction results. Prediction results obtained by RBFNN are observed to yield satisfactory high correlation coefficients and satisfactory low mean square error values when compared to the results in the previous studies, indicating the efficiency of the proposed model.

Application of bio-preservation to enhance food safety: A review

  • Nethma Samadhi Ranathunga;Kaushalya Nadeeshani Wijayasekara;Edirisinghe Dewage Nalaka Sandun Abeyrathne
    • 한국식품저장유통학회지
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    • 제30권2호
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    • pp.179-189
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    • 2023
  • Consumers and industry experts frequently have negative perceptions of most chemical preservatives. Although most people concede that they cannot resolve global food waste issues without preservatives, they prefer products without chemical preservatives. Numerous emerging technologies is now surpassing conventional methods for mitigating microbial food deterioration in response to consumer demand and fundamental health and safety considerations, including biological antimicrobial systems such as using food-grade microorganisms and their metabolites primarily originating from microorganisms, plants, and animals. Microbial compounds, including bacteriocins, bacteriophages, and anti-fungal agents, plant extracts such as flavonoids and essential oils; and animal-originated compounds, such as lysozyme, chitosan, and lactoferrin, are considered some of the major bio-preservatives. These natural compounds can be used alone or with other preservatives to improve food safety. Hence, the use of microbes or their metabolic byproducts to extend the shelf life of foods while maintaining safety standards is known as bio-preservation. To manufacture and consume foods in a safe condition, this review primarily aims to broaden knowledge amongst industry professionals and consumers regarding bio-preservation techniques, bio-preservatives, their classifications, and distinctive mechanisms to enhance food safety.

비파괴 분석을 활용한 조선왕릉 태릉 석조물의 손상특성 분석 (Deterioration Characteristic Analysis for Stone Properties in the Taereung Royal Tomb of the Joseon Dynasty using Nondestructive Analysis)

  • 이명성;최명주;이태종;전유근
    • 헤리티지:역사와 과학
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    • 제53권2호
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    • pp.222-241
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    • 2020
  • 조선왕릉 태릉은 중종의 계비인 문정황후의 무덤으로 다양한 종류의 석조물(석물 24기, 봉분석재 144개)이 배치되어 있다. 이 석조물은 모두 중조립질의 흑운모화강암을 사용하여 제작하였다. 석조물의 주요 손상양상은 물리적 손상과 생물오염으로 확인되며 이 중에서 박리박락(145기), 입상분해(138기), 보수물질(156기)과 함께 생물오염인 조류(154기), 지의류(165기), 선태류(97기)가 높은 발생빈도를 보인다. 특히 생물학적 손상(조류)이 가장 심각한 상태(3등급 이상이 전체 석물의 94%)로 즉각적인 보존처리가 요구되며 부분적으로는 박리박락과 입상분해 등도 중장기적인 보존관리가 필요할 것으로 판단된다. 에코팁 경도와 초음파탐사 결과, 석재의 약 70%이상이 물성이 상당히 취약한 것으로 나타났다. 초분광 분석에서도 봉분석재 표면의 80% 이상에서 생물이 서식하는 것으로 분석되었으며 이 부분에는 P(인), S(황), Cl(염소), Ca(칼슘)이 높게 검출되었다. 이는 태릉이 수백 년 동안 야외에 위치하고 있어 물리적, 화학적 및 생물학적 요인 등에 의해 풍화작용을 받아 왔기 때문이다. 따라서 태릉 석조물 중 물리적 풍화등급이 높은 석물은 물성을 보강하기 위해 강화처리가 필요한 것으로 판단되며 생물은 석재의 손상을 유발할 수 있는 가능성이 높기 때문에 건식 및 습식 세정으로 제거해야 한다. 또한 보존처리 이후 생물의 재발생을 지연하기 위해서는 봉분에 흘러내린 토사를 정기적으로 정리해줄 필요가 있고 장기적으로 보존상태에 대한 모니터링이 필요하다.