• 제목/요약/키워드: Critical Damage Value

검색결과 108건 처리시간 0.026초

A Comparative Study on Marine Transport Contract and Marine Insurance Contract with Reference to Unseaworthiness

  • Pak, Jee-Moon
    • Journal of Korea Trade
    • /
    • 제25권2호
    • /
    • pp.152-177
    • /
    • 2021
  • Purpose - This study analyses the excepted requirement and burden of proof of the carrier due to unseaworthiness through comparison between the marine transport contract and marine insurance contract. Design/methodology - This study uses the legal analytical normative approach. The juridical approach involves reviewing and examining theories, concepts, legal doctrines and legislation that are related to the problems. In this study a literature analysis using academic literature and internet data is conducted. Findings - The burden of proof in case of seaworthiness should be based on presumed fault, not proved fault. The burden of proving unseaworthiness/seaworthiness should shift to the carrier, and should be exercised before seeking the protections of the law or carriage contract. In other words, the insurer cannot escape coverage for unfitness of a vessel which arises while the vessel is at sea, which the assured could not have prevented in the exercise of due diligence. The insurer bears the burden of proving unseaworthiness. The warranty of seaworthiness is implied in hull, but not protection and indemnity policies. The 2015 Act repeals ss. 33(3) and 34 of MIA 1906. Otherwise the provisions of the MIA 1906 remain in force, including the definition of a promissory warranty and the recognition of implied warranties. There is less clarity about the position when the source of the loss occurs before the breach of warranty but the actual loss is suffered after the breach. Nonetheless, by s.10(2) of the 2015 Act the insurer appears not to be liable for any loss occurring after the breach of warranty and before there has been a remedy. Originality/value - When unseaworthiness is identified after the sailing of the vessel, mere acceptance of the ship does not mean the party waives any claims for damages or the right to terminate the contract, provided that failure to comply with the contractual obligations is of critical importance. The burden of proof with regards to loss of damage to a cargo caused by unseaworthiness is regulated by the applicable law. For instance, under the common law, if the cargo claimant alleges that the loss or damage has been caused by unseaworthiness, then he has the burden of proof to establish the followings: (i) that the vessel was unseaworthy at the beginning of the voyage; and that, (ii) that the loss or damage has been caused by such unseaworthiness. In other words, if the warranty of seaworthiness at the inception of the voyage is breached, the breach voids the policy if the ship owner had prior knowledge of the unseaworthy condition. By contrast, knowingly permitting the vessel to break ground in an unseaworthy condition denies liability only for loss or damage proximately caused by the unseaworthiness. Such a breach does not, therefore, void the entire policy, but only serves to exonerate the insurer for loss or damage proximately caused by the unseaworthy condition.

FE analysis of RC structures using DSC model with yield surfaces for tension and compression

  • Akhaveissy, A.H.;Desai, C.S.;Mostofinejad, D.;Vafai, A.
    • Computers and Concrete
    • /
    • 제11권2호
    • /
    • pp.123-148
    • /
    • 2013
  • The nonlinear finite element method with eight noded isoparametric quadrilateral element for concrete and two noded element for reinforcement is used for the prediction of the behavior of reinforcement concrete structures. The disturbed state concept (DSC) including the hierarchical single surface (HISS) plasticity model with associated flow rule with modifications is used to characterize the constitutive behavior of concrete both in compression and in tension which is named DSC/HISS-CT. The HISS model is applied to shows the plastic behavior of concrete, and DSC for microcracking, fracture and softening simulations of concrete. It should be noted that the DSC expresses the behavior of a material element as a mixture of two interacting components and can include both softening and stiffening, while the classical damage approach assumes that cracks (damage) induced in a material treated acts as a void, with no strength. The DSC/HISS-CT is a unified model with different mechanism, which expresses the observed behavior in terms of interacting behavior of components; thus the mechanism in the DSC is much different than that of the damage model, which is based on physical cracks which has no strength and interaction with the undamaged part. This is the first time the DSC/HISS-CT model, with the capacity to account for both compression and tension yields, is applied for concrete materials. The DSC model allows also for the characterization of non-associative behavior through the use of disturbance. Elastic perfectly plastic behavior is assumed for modeling of steel reinforcement. The DSC model is validated at two levels: (1) specimen and (2) practical boundary value problem. For the specimen level, the predictions are obtained by the integration of the incremental constitutive relations. The FE procedure with DSC/HISS-CT model is used to obtain predictions for practical boundary value problems. Based on the comparisons between DSC/HISS-CT predictions, test data and ANSYS software predictions, it is found that the model provides highly satisfactory predictions. The model allows computation of microcracking during deformation leading to the fracture and failure; in the model, the critical disturbance, Dc, identifies fracture and failure.

Protective Effect of Fucoidan Extract from Ecklonia cava on Hydrogen Peroxide-Induced Neurotoxicity

  • Park, Seon Kyeong;Kang, Jin Yong;Kim, Jong Min;Park, Sang Hyun;Kwon, Bong Seok;Kim, Gun-Hee;Heo, Ho Jin
    • Journal of Microbiology and Biotechnology
    • /
    • 제28권1호
    • /
    • pp.40-49
    • /
    • 2018
  • We evaluated the antioxidant activity and neuronal cell-protective effect of fucoidan extract from Ecklonia cava (FEC) on hydrogen peroxide ($H_2O_2$)-induced cytotoxicity in PC-12 and MC-IXC cells to assess its protective effect against oxidative stress. Antioxidant activities were examined using the ABTS radical scavenging activity and malondialdehyde-inhibitory effect, and the results showed that FEC had significant antioxidant activity. Intracellular ROS contents and neuronal cell viability were investigated using the DCF-DA assay and MTT reduction assay. FEC also showed remarkable neuronal cell-protective effect compared with vitamin C as a positive control for both $H_2O_2$-treated PC-12 and MC-IXC cells. Based on the neuronal cell-protective effects, mitochondrial function was analyzed in PC-12 cells, and FEC significantly restored mitochondrial damage by increasing the mitochondrial membrane potential (${\Delta}{\Psi}m$) and ATP levels and regulating mitochondrial-mediated proteins (p-AMPK and BAX). Finally, the inhibitory effects against acetylcholinesterase (AChE), which is a critical hydrolyzing enzyme of the neurotransmitter acetylcholine in the cholinergic system, were investigated ($IC_{50}$ value = 1.3 mg/ml) and showed a mixed (competitive and noncompetitive) pattern of inhibition. Our findings suggest that FEC may be used as a potential material for alleviating oxidative stress-induced neuronal damage by regulating mitochondrial function and AChE inhibition.

Correlation Between Mechanical Behavior and Electrical Resistance Change in Carbon Particle Dispersed Plastic Composite

  • Song, D.Y.;Takeda, N.;Kim, J.K.
    • 대한기계학회:학술대회논문집
    • /
    • 대한기계학회 2001년도 춘계학술대회논문집A
    • /
    • pp.377-382
    • /
    • 2001
  • Mechanical behavior and electrical resistance change of CPDP (carbon particle dispersed plastic) composite consisting of epoxy resin and conductive carbon particle were investigated under monotonic loading and repeated loading-unloading. The electrical resistance almost linearly increased with increasing strain during loading and the residual electrical resistance was observed even after removing load. The value of the residual electrical resistance was dependent on the maximum strain under the applied stress. This result suggests that the estimation of maximum strain (i.e., damage) is possible by the measuring electrical resistance of composite. The behavior of electrical resistance change during and after loading was discussed on the basis of the results of microscopic deformation and fracture observation. Moreover, the relationship between the volume fraction of carbon particle and the electrical resistivity of CPDP was investigated in relation to the percolation theory. Simulation model of percolation structure was established by Monte Carlo method and the simulation result was compared to the experimental results. The electrical resistance change under applied loading was analyzed quantitatively using the percolation equation and a simple model for the critical volume fraction of carbon particle as a function of the mechanical stress. It was revealed that the prediction was in good agreement with the experimental result except in the region near the failure of material.

  • PDF

현장 및 실내조사를 통한 일반국도교량의 화재위험요소 분석 (Investigation of Potential Fire Hazard Resources of Bridges on National Routes by Field and Web-based Satellite)

  • 김용재;김승원;안호준;공정식;박철우
    • 한국도로학회논문집
    • /
    • 제19권6호
    • /
    • pp.105-115
    • /
    • 2017
  • PURPOSES : The occurrence of unexpected disasters, including fire events, increases as the road network becomes complicated and traffic volume increases. When a fire event occurs on and under bridges, the damage extensively influences direct damage to structures, vehicles, and human life and secondary socioeconomic issues owing to traffic blockage. This study investigated potential fire-hazard risks on bridges of the Korean national route road. METHODS : The investigation was conducted using field investigation and analysis with satellite pictures and road views from commercial websites and the Bridge Management System (BMS). From the filed investigation, various potential fire resources were identified. The satellite pictures and road views were helpful in measuring and recognizing conditions underneath bridges, stowage areas, etc. RESULTS : There are various potential fire resources underneath bridges such as piled agricultural products, parked petroleum tanks, construction equipment, and attached high-voltage cables. A total of 94.6% of bridges have underneath clearances of less than 15 m. A bridge underneath volume that can stow a potential fire hazard resource was $7,332m^3$ on average, and most bridges have about $4,000m^3$ of space. Based on the BMS data, the amounts of PSC and steel girders were 29% and 25%, respectively. CONCLUSIONS : It was found that the amount of stowed potential fire hazard resources was proportional to the underneath space of bridges. Most bridges have less than 15 m of vertical clearance that can be considered as a critical value for a bridge fire. The fire risk investigation results should be helpful for developing bridge fire-protection tools.

발파진동에 의한 절리암반 지하공동의 낙석발생 예측에 관한 수치해석적 연구 (Numerical Study for Prediction of Rock Falls Around Jointed Limestone Underground Opening due to Blast Vibration)

  • 김현수;김승곤;조상호
    • 화약ㆍ발파
    • /
    • 제34권3호
    • /
    • pp.10-16
    • /
    • 2016
  • 최근 석회석광산은 분진 소음 등 환경적인 문제와 함께 석회석 품위 저하 현상으로 갱내 채광이 증가하고 있다. 석회석을 파쇄시키기 위한 파쇄 시설을 갱내 설치하려면 대규모 지하공동이 필요하게 되며, 공동의 규모가 커짐에 따라 낙석이나 낙반의 발생 가능성이 높아지게 된다. 그리고 석회석 지하공동 주변 암반은 다양한 절리가 발달하여 낙석 발생에 영향을 미치는 것으로 알려져 있다. 본 연구에서는 채광 발파 시 대형갱도 내 낙석발생 여부 관찰과 발파진동 계측을 수행하여, 이를 바탕으로 불연속면 수치해석 소프트웨어인 UDEC를 이용하여 절리암반 동해석 모델을 제안하고 발파진동 여기에 의한 대형 지하갱도의 낙석 발생을 해석하였다. 또한 절리암반 모델에 다양한 절리특성(경사각, 간격)의 변화와 발파굴착 손상영역을 고려하였다.

지진 구조 손상도 예측을 위한 지반 운동 수정법 평가 (Evaluation of Ground Motion Modification Methodologies for Seismic Structural Damage)

  • 허영애
    • 한국구조물진단유지관리공학회 논문집
    • /
    • 제17권4호
    • /
    • pp.112-118
    • /
    • 2013
  • 성능기반 내진설계 및 평가의 정밀도 향상에 있어서 적절한 지반운동 데이터 선정과 이를 합리적으로 수정하는 것에 대한 중요성이 부각되고 있다. 지반운동 데이터를 수정하는 방법으로 단일 진폭수정법 (Amplitude scaling)이 널리 사용되고 있으나, 단일 진폭수정법에서 는 단 하나의 주기, 특히 구조물의 고유주기에서만 그 응답스펙트럼 값이 설계스펙트럼의 값과 일치하도록 수정되므로 특정 지역의 지진 재해도에 대해 일관성 있는 구조 해석 결과를 기대하기 어렵다. 따라서 이에 대해 여러 가지 대안 수정법들이 제시되고 있으나 이들의 타당성을 평가할 수 있는 방안이 마련되어 있지 않다. 본 논문에서는 단일 진폭수정법의 문제점을 설명하고, 대안 수정법과 비교 평가하기 위한 구조 응답에 대한 회귀 모델을 제시하는데 목표를 두었다. 대안 수정법으로써 전체 주기 범위에서 지반운동의 응답스펙트럼이 설계스펙트럼의 값과 일치하도록 수정하는 다중 스펙트럼 수정법을 고려하였다. 설계스펙트럼은 ASCE7-05에 따라 구하였다.

Value of Bronchoalveolar Lavage Fluid Cytology in the Diagnosis of Pneumocystis jirovecii Pneumonia: A Review of 30 Cases

  • Sung, Ji-Youn;Han, Joung-Ho;Oh, Young-Lyun;Suh, Gee-Young;Jeon, Kyeong-Man;Kim, Tae-Eun
    • Tuberculosis and Respiratory Diseases
    • /
    • 제71권5호
    • /
    • pp.322-327
    • /
    • 2011
  • Background: Pneumocystis jirovecii is a fungus that has become an important cause of opportunistic infections. We present a summary of the clinical status and findings from bronchoalveolar lavage (BAL) of patients with Pneumocystis jirovecii pneumonia (PJP). Methods: We selected 30 cases of PJP that were proven through a surgical specimen evaluation. BAL fluid cytology was reviewed, and agreement with the initial diagnosis was evaluated. Results: All 30 cases of PJP occurred in immunocompromised patients. Only 15 of the 30 cases were initially diagnosed as PJP. We found PJP in 13 of the 15 cases that were negative at the initial diagnosis. The most characteristic finding of PJP was frothy exudates, and BAL fluid tended to show rare neutrophils. Two of seven patients with PJP and diffuse alveolar damage (DAD) revealed no frothy exudates in BAL fluid. Conclusion: BAL fluid cytology was reconfirmed as a sensitive and rapid method to diagnose PJP. We must be aware of the possibility of PJP to maintain high diagnostic sensitivity. We cannot exclude PJP in cases of PJP with DAD, even if frothy exudates are not observed in the BAL fluid.

5개의 연결부를 가지는 역진자형 석조문화재의 동적 해석모델 및 안정성 연구 (A Study on Dynamic Analysis Model and Stability of Stone Cultural Properties of Inverted Pendulum Type with 5 Joints)

  • 최재성
    • 한국구조물진단유지관리공학회 논문집
    • /
    • 제25권3호
    • /
    • pp.21-30
    • /
    • 2021
  • 건축문화재들은 다양한 환경적 요인들로 인해 많은 손상이 발생된다. 손상된 문화재를 보존하기 위해서 예방보존 및 장기적인 보존관리가 더욱 중요해지고 있다. 그래서 정기적인 점검 시에 적용 가능한 과학적인 비파괴 검사 방법에 대한 연구가 요구되고 있다. 관련된 연구를 위해서, 여러 문화재들 중에서 높은 깃대 형상의 당간을 연구 대상으로 선정하였다. 보존되고 있는 당간들 중에서 보물 제49호 나주 석당간을 선정하여, 구조 안정성을 평가하기 위한 분석 기법에 대한 기초적인 연구를 진행하였다. 이상화된 모델을 제시하고, 다자유도 운동방정식을 유도하였다. 그리고 연결부 위치별 임계 강성 값을 추정할 수 있는 식을 제시하였다.

파단방지를 위한 튜브인발공정 최적 금형형상 설계에 관한 연구 (Optimal Die Profile Design in Tube Drawing Process for Prevention of Material Fracture)

  • 이상곤;김상우;이영선;이정환;김병민
    • 한국정밀공학회지
    • /
    • 제23권11호
    • /
    • pp.78-84
    • /
    • 2006
  • The objective of this study is to design the optimal die profile that can prevent material fracture in the tube drawing process for automobile steering input shaft. First, the CDV(Critical Damage Value) of material is obtained by the compression test and FE-analysis. The occurrence of fracture is estimated by the FE-analysis considering the CDV. In order to achieve the objective of this study, optimization technique and FE-analysis are applied. FPS(Flexible Polyhedron Search) method, which is one of the non-gradient optimization techniques often used in engineering, is used to search optimal die profile. The drawing die profile is represented by Bezier-curve to generate all the possible die profile. Using FPS method and FE-analysis the optimal drawing die profile is determined. To verify tile effectiveness of the redesigned optimal die, the tube drawing experiment is performed. In the experimental result, it is possible to produce sound product without material fracture using the redesigned optimal die.