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Abstract

Bills of Lading are transferable documents of title and the transfer of document results in the transfer of the rights incorporated in it. Some of B/L are additionally negotiable. However the legal meaning of these two terms isn’t the same what is not respected in practice. Historically there is also a difference in legal grounds and scope of rights represented and transferred by negotiable bills of lading according to British, American and continental law. An important role in this differentiation was played by the doctrine of privity of contract. This ultimately affects the legal position and scope of the acquired rights of legitimate holders of bills of lading, which are considered to be “negotiable”, including the right to obtain claims from the carrier for cargo damage.

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Authors and Affiliations

Maria Dragun-Gertner
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Abstract

A laser measurement system for measuring straightness and parallelism error using a semiconductor laser was proposed. The designing principle of the developed system was analyzed. Addressing at the question of the divergence angle of the semiconductor laser being quite large and the reduction of measurement accuracy caused by the diffraction effect of the light spot at the longworking distance, the optical structure of the system was optimized through a series of simulations and experiments. A plano-convex lens was used to collimate the laser beam and concentrate the energy distribution of the diffraction effect. The working distance of the system was increased from 2.6 m to 4.6 m after the optical optimization, and the repeatability of the displacement measurement is kept within 2.2 m in the total measurement range. The performance of the developed system was verified by measuring the straightness of a machine tool through the comparison tests with two commercial multi-degree-of-freedom measurement systems. Two different measurement methods were used to verify the measurement accuracy. The comparison results show that during the straightness measurement of the machine tool, the laser head should be fixed in front of the moving axis, and the sensing part should move with the moving table of the machine tool. Results also show that the measurement error of the straightness measurement is less than 3 m compared with the commercial systems. The developed laser measurement system has the advantages of high precision, long working distance, low cost, and suitability for straightness and parallelism error measurement.
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Bibliography

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Authors and Affiliations

Peng Xu
1
Rui Jun Li
1
Wen Kai Zhao
1
Zhen Xin Chang
1
Shao Hua Ma
1
Kuang Chao Fan
1

  1. Hefei University of Technology, School of Instrument Science and Opto-Electronics Engineering, Hefei, China
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Abstract

This paper presents new results for the dynamic behaviour of fluid around a rotating turbulator in a channel. The turbulator has a propeller form which is placed inside a flat channel. The research was carried out using 3D numerical simulation. The rationale of the experiment was as follows: we put a propeller-turbulator inside a flat channel, and then we insert a water flow inside the channel. The turbulator rotates at a constant and uniform speed. The main points studied here are the effect of the presence of turbulator and its rotational direction on the flow behaviour behind the turbulator. The results showed that the behaviour of flow behind the turbulator is mainly related to the direction of turbulator rotating. Also, the studied parameters affect coefficients of drag force and power number. For example, when the turbulator rotates in the positive direction, the drag coefficient decreases in terms of rotational speed of the turbulator, while the drag coefficient increases in terms of rotational speed when the turbulator rotates in the negative direction.
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Authors and Affiliations

Elhadi Zoubai
1
Houssem Laidoudi
1
Ismail Tlanbout
1
Oluwole Daniel Makinde
2

  1. University of Science and Technology of Oran Mohamed-Boudiaf, Faculty of Mechanical Engineering, Laboratory of Sciences and Marine Engineering, BP 1505, El-Menaouer, Oran, 31000, Algeria
  2. Stellenbosch University, Faculty of Military Science, Private Bag X2, Saldanha 7395, South Africa

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