Journal of Naval Sciences and Engineering

71-90

Authors: Tansel ERKMEN

Turkey has great potential in liquified gas bunkering industry. Early application of liquified gas terminal investments is high likely to generate substantial income for the shipping industry of Turkey and to its economy as a whole. The marine shipping industry is facing challenges to reduce engine exhaust emissions and greenhouse gases (GHGs) from their ships. LNG is a potential solution for meeting these requirements. Progress in the marine fuel industry has become critical to shipowners and cargo owners, since fuel consumption accounts for much of the total cost of travel and can be a significant part of total transport costs. LNG bunker in Northern Europe is advancing, however, worldwide lack of supply is undermining the spread of LNG bunkering. Therefore, providing security of supply in the Eastern Mediterranean could represent an important milestone towards LNG supply chain implementation.

100-109

Authors: Tunç MEDENİ, Tolga MEDENİ, Demet SOYLU

This paper aims to reflect on the increasing need for the electronic cross- country service provision, and provide certain solution suggestions to address related issues, benefiting from the experience and expertise of the coauthors. While the current state is being presented and suggestions are being provided, examples from transportation and logistics areas are given, with a particular focus on food supply chain and thus technology support in agriculture and livestock management activities. Accordingly, the paper is finalised with a specific suggestion on block-chain-based cross-country information system for livestock supply chain management. The resulting work is hoped to contribute to the development and provision of high quality, user-oriented electronic cross-country services.

121-139

Authors: Yaşanur KAYIKÇI

An efficient, effective and sustainable freight transport network is a crucial determinant for economic growth and development. This network needs to be structured as resilient as practicable and also quickly adoptable and adaptable to meet the needs of transport users and provide alternative optimal routes, if it is affected by disruptive events. This paper presents a route selection model which supports transport planners to decide rapidly on an optimal transport route in case of disruption in a multimodal freight transport network. An integrated method based on Fuzzy Analytic Hierarchy Process and Fuzzy Goal Programming is developed to support the decision of route selection.

1-22

Authors: Gülçin SEDEFOĞLU, Gülşen AKMAN

Nowadays competition among companies is rapidly increasing with the progress of technology. In order to stand out in this competition environment, companies need to be renovated in their own fields. Many companies use lean manufacturing techniques to achieve this renewal. This study was performed in a company operating in the automotive industry. In this study, the production line which will be improved is determined by using the Analytical Hierarchy Process method. Next, Value Stream Mapping has been applied to the determined product line. We revealed the current situation of the production line by drawing current state mapping. Second, the future state mapping is drawn up to solve the problems presented in the current state mapping, and an action plan was presented for improvements.

32-53

Authors: İbrahim GÜLATAŞ, Selçuk BAKTIR

The Unmanned Aerial Vehicle (UAV) technology is a rapidly emerging technology and it has found widespread usage. While UAVs are still in their development phase without any existing commonly accepted standards for their underlying technologies and their forensic investigation, they have an increasing record of criminal usage. This urges the research community to develop techniques to detect and prevent illegal usage of UAVs. With this work, we present a seven-phase UAV digital forensics investigation framework to standardize the investigation process for UAVs. We tested our framework on the DJI Phantom III Professional UAV which is one of the most popular commercial UAVs in the market. Three kinds of forensic artifacts are found on the sample UAV and these artifacts are examined deeply. Two of the artifacts are log files stored as binary files and the other artifact is the EXIF header of the images that are captured by UAV's onboard camera. As a result of our investigation, we are able to regenerate the flight path of the UAV. As a final step of our research, we compare our investigation framework with the existing framework on the literature and reveal the differences of both frameworks.

7

Authors: Tolga ENSARİ

In this article, we use projected gradient descent nonnegative matrix  factorization (NMF-PGD) method and make pattern recognition analysis  on ORL face data set. Face recognition is one of the critical issues  in our life and some security, daily activities and operations use  this well known application area. NMF-PGD is a type of nonnegative  matrix factorization (NMF) which defined in the literature. In the  study, derived NMF-PGD definition and algorithm has been used in order  to classify the ORL face images. We give the experimental results in a  table and graph. According to experiments, face recognition accuracy  rates have different accuracy values because of the k - lower rank  value. We change k-values between 25 and 144 to see the performance of  NMF-PGD. At the end, we make some analysis and comments on the  recognition rates. Additionally, NMF-PGD can also be used for  different kind of pattern recognition problems.

14

Authors: Hakan DEMİR, Mehmet Bilge Kağan ÖNAÇAN, Ahmet DURMAZ, Mehmet YÜKSEL

The main motivation of this research is to examine effects of “5S applications” which is similar to Kaizen philosophy, on excellence perceptions of firms in food sector. In this context, a questionnaire was applied to the logistics department employees of randomly chosen firms that operate in Istanbul and Kocaeli districts. Data obtained from surveys were subjected to structural equation modeling test. According to the results, overall 5S applications showed positive and significant effects on excellence in business variable, excluding “cleaning”. Moreover, outstanding effect of “sustain” application is an intriguing finding of this research. With the importance that efficiency concept has today, it is evaluated that the results obtained in this study will be beneficial to organizations, especially during their process improvement activities by being the first research in food sector that seeks connection between the 5S and excellence.

8

Authors: Ertan YAKICI

In this case study, we have investigated the optimal design of a network of warehouses to be pre-positioned for humanitarian relief operations to be executed when expected disasters happen. A model which is previously introduced in the literature is applied with the most recent data. The model responds to decision requirements in both locations of warehouses and allocation of resources to these warehouses, assuming the disaster pattern of last decade will continue. A sensitivity analysis is also conducted to observe how the average response time changes as the allowed number of warehouses increases.

13

Authors: Hakan Selim Canca

The use of force is resorted by States as a form of dispute settlement generally as a last resort. But Article 2(3) of the United Nations (UN) Charter states that all members shall settle their international disputes by peaceful means. Article 2(4) bans the unilateral use or threat of force by States. In the customary international law, Article 2(4) is interpreted as a prohibition against the use of force focusing on restricting the use of military instruments. This instrument-based interpretation of the use of force causes the responsibility of States which deploys cyber instruments to cause physical damage in the target States’ critical infrastructures, remain outside the scope of Article 2(4). There are doctrinal difficulties in examining current international law on use of force and self-defense in cyberspace, while the legal frameworks for defining the parameters of operations in cyberspace are not clear. As being unforseen until this age of information and cyber technology, the prohibition of the use of force interpreted from Article 2(4) should be evolved to cover coercive uses of cyber instruments being used to have destructive effects in the enemy’s physical infrastructures such as telecommunications, transportation, power systems, finance and emergency services. Categorizing the cyber attacks as having physical effects to critical infrastructure and not having any physical effects can be the first step to solve the problem of evolving the article to cover cyber attacks within the concept of use of force. Then the efforts may be concentrated on the cyber attacks having physical effects on the enemy’s infrastructures to be considered as a use of force. The main problem is that there would be an unwillingness of the powerful States which are likely to use the opportunities of cyberspace in Inter-State coercion to evolve the interpretation of the article, while the technology-dependent or powerless States would have a volition to evolve the Article.

22

Authors: Ali Saygun SAYGI, Ersoy BEŞER, Murat ÜNLÜ

High frequency switched-mode DC-DC converters are widely used in industry such as battery charging, renewable energy, fuel-cell, power factor correction, LED lighting applications, due to their low response time, easy controlling and high power density. However, at high switching frequency, switching losses, electromagnetic interference (EMI) and lower efficiency become substantial problem. These problems must be eliminated or reduced by using additional passive and active snubber cells in order to operate the converter with soft switching (SS) instead of hard switching (HS). In this paper, properties of soft switching methods named as zero voltage transition (ZVT), zero current transition (ZCT), and zero voltage zero current transition (ZVZCT) developed by combining the ZVT and ZCT, zero voltage switching (ZVS) and zero current switching (ZCS) are studied and discussed, simulations of soft switching DC to DC boost converters including these methods are accomplished for 500W and 1kW power at switching frequency of 100 kHz.

8

Authors: Yusuf Kavurucu, Tolga Ensari

The smart home system has been developed since 1980s. Its first application was built in 1984, in Turkey. In these first steps, the focused group was only people without disabilities. Initially, manufacturers tried to create all-in-one systems, yet the final products were all gadget-like and minimalistic. (Energy control units, security systems, light controllers, etc.) Smart homes have various application areas. Controlling central air conditioning in modern high-rise buildings, malls with parameters such as temperature and humidity is an example of real-time programming of these devices. The main idea here is to control the capacity of air conditioning equipment in order to save energy, thus saving money. The goal of our article is to make life easier with the help of computer science. With our knowhow and extra research of available information, by using the software portions and the hardware components, we aim to create a sensor-based smart home system. Basically, the system is getting the data from the sensors placed in different locations in home and transfer it to terminal via Wi-Fi. In the flowchart, the most crucial part is to connect the hardware problem-free. Next thing is to upload the code for these modules to an EEPROM computer to establish connection between devices and to display the information in the terminal screen. The designed system looks like an autonomous computer which can control the air conditioning with the help of various sensors with precision.

13

Authors: Tolga Onel, Mehmet Bilge Kağan Önaçan, Erkan Kıyak

Recent advances in computer technologies result in the development of E-Learning and Learning Management Systems. They provide mechanisms to organize course contents and training systems including interactions of trainers and trainees. Moreover, virtual reality systems emerge in the training and education systems to increase the trainee participation at the process and visualize the training subject. Increasing data transfer rates of the computer networks also made distant learning activities possible. Moreover, the economical solutions with the cloud computing technologies for the abovementioned systems come up. All these improvements lead the technology towards smart classrooms. It seems to alter the educational habits towards the flipped and the blended learning. In this study, general information about emerging educational technologies is given and a short evaluation with suggestions is presented.

19

Authors: Cengiz Erdönmez

The use of intelligent technologies in education increases every day. There are a lot of new technologies implemented lately. Intelligent White Boards (IWBs) are the most popular devices among them and preferred to use in education nowadays. But the use of these technologies requires compatible and supportable smart educational contents (SECs). It does not seem possible at this stage to find such SECs ready to use for university lectures. Undoubtedly one of the reason behind this issue is that contents of some lectures or their syllabuses show huge differences between universities, even from lecturer to lecturer. In addition, some of the universities could open some courses only for their specific needs. In this paper, our aim is to figure out the necessary characteristics of SECs and the lecturers who need SECs in their lessons, should take care of while preparing their own SECs.