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A study on RFID adoption

A study on RFID adoption for vehicle tracking in container terminal, With the advance of globalization, transportation is playing an important role. Numerous containers are transported from port to port, from vehicle to vehicle, every day. As transportation distances become longer and the volume of international transportation increases, many companies are involved in the transportation of one assignment from one locationto another. It is hard to manage the containers, such as how to arrange the container schedule and route for avoiding heavy traffic; how to track the container locations continuously. Additionally, containers look the same and it is also hard to identify them in the terminal. These challenges make tracking of the vehicles and containers very important. Efficient information can help the users to manage their transportations. This is the reason why there are numerous studies using information and communication technologies in vehicle and container tracking.To deal with this problem, recently developed technology provides an efficient way. Radio Frequency Identification (RFID) is an emerging technology that uses wireless radio to identify objects from a distance without requiring line of sight or physical contact (Borriello, 2005). RFID enables the user to capture real-time information in fast moving and bulky product flows with the aim of achieving a high degree of efficiency and assuring high quality. The components of a typical RFID system include an RFID tag, an RFID reader, an RFID antenna, an RFID middleware and the backend system. The RFID tag is the identification device attached to the item to be tracked. The RFID reader and antenna are devices that can recognize the presence of RFID tags and read the information stored on them. The aim of RFID middleware is to process the transmission of information between the reader and other applications after receiving the information. Middleware is software that facilitates communication between the system and the RFID devices. Figure 1 shows a typical RFID system and illustrates how the elements fit together. Recently, the lower costs and the increasing capabilities of the RFID technique attract attentionin keeping track and monitoring the containers in the terminal (Hsu, Shih & Wang, 2009; Park, Dragovic & Kim, 2009; Ngai et al., 2010). Woo, Choi, Kwak and Kim (2009) proposed an activity product state tracking system architecture which is able to track products even when they are in a box or a container. Abad et al. (2009) developed an RFID-based system for traceability and cold chain monitoring of food. Wang et al. (2009) proposed a RFID-based decision support system to monitor, trace and track products in containers. Chao and Lin (2009) analyzed critical factors affecting the adoption ofacontainer security service, which is composed of auto-detection and RFID technologies, from the shippers’ perspective. Cao and Xiao (2011) analyzed a propagation prediction model and the performance of a container RFID system under metallic container production circumstances. These applications encourage study of RFID to realize vehicle tracking in container terminals. However, although numerous studies involving the installation ofRFID have demonstrated the benefits of better container handling efficiency, a relative lack of research concerningtracking and monitoring vehiclemovement in the container terminal environmentis appearance. Vehicle tracking is a way to improve companyefficiency and in effect, increase profitability, especially in the business of large vehicle fleets(Hsieh, Yu, Chen & Hu, 2006). The tracking system is the enabling technology, and is the key to release the value trapped in asset management. By its non-contact, scan-based data reading characteristics, it automates the asset tracking and data acquisition that enables an enterprise to locate vehicles (i.e. cars, trucks, etc.) and even uses location information to optimize services. With the help of tracking information, the manager is able to access one or moredriver locationsand gets their status information on areal-time basis (i.e. checking if the drivers execute the order;if they follow the driving routes;if there is any traffic congestion, etc.). However, implementing RFID as a vehicle tracking system is difficult as the container terminal environment, which involvesdifferent transport vehicles for onward transportation,

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Examining green production

Examining green production and its role within the competitive strategy of manufacturers, The term “green” is now widely used, although its origins lie more in the popular press than the scientific community. Increasingly, the term is used interchangeably on the more established “sustainability”concept, and so this means taking a holistic view of environmental, social and economic impact (Dobers & Wolff, 2000; Kleindorfer, Singhal, & van Wassenhove, 2005; Rahimifard & Clegg, 2007; Saha&Darnton, 2005; Seliger, Kim, Kernbaum & Zettl, 2008).Elkington (1997, p. 22) presents the challenge to achieve sustainability as “an unprecedented source of commercial opportunity for competitive companies, through technological innovation and improved eco-efficiency”. The underpinning assumption is that financial success can be made consistent with an ethical, environment and society compliance (Dobers & Wolff, 2000; Mohanty &Deshmukh, 1998; Stead &Stead, 2000).Accordingly, green manufacturers are those that make a commitment to a wide and long-term assessment of the impact of their activities and, thereby, to influence issues such as people’s quality of life and well-being, protection and security, economic growth, social and economic justice (Hart, 1995; Saha &Darnton, 2005). As presented later, we see green production is now commonly seen as “the application of environmentally and socially sensitive practices to reduce the negative impact of manufacturing activities while, at the same time, harmonising the pursuit of economic benefits”. Green production is rapidly growing in importance (Brandt, 2007; Corbett &Klassen, 2006; Dills &Stone, 2007; Stead &Stead, 2000). As populations grow, and emerging economies expand, the planet’s ecosystems and resources are experiencing tremendous challenges (de Burgos &Cespedes, 2001; Esty &Winston, 2009; Hart, 1995; Industry Today, 2010; Kleindorfer et al., 2005; Mohanty &Deshmukh, 1998). Production systems, that supply the growing demand for goods, are linked to adverse environment impacts (Frosch &Gallopoulos, 1989).For example, as countries such as China enjoy the benefits of lifestyles close to those of the western societies, the impact of human activities is estimated to rise ten-fold by 2050 (Lisney, Riley & Banks, 2003). Urgent measures are neededto be taken to achieve a pivotal change in the way society in general, and industry in particular, manages natural resources (Brandt, 2007; Lee, 2008; Lisney et al., 2003). As a consequence, many governments have formally embraced environmental policies and regulations, and the free market is placing a clear premium on those companies who are ableto offer green credentials (Brandt, 2007; Miles &Covin, 2000; Saha &Darnton, 2005; Sarkis &Cordeiro, 2001; Yang, Lin, Chan & Sheu,2010).For “production”based companies, such green credentials can be achieved in a number of ways including the materials used within products, how products are produced, and the ease of dealing with a product at the end of its life. Recent years have seen a rapid expansion in both the interest and body of literature on green production.In 2001, Dangayach andDeshmukh (2001) recognised the relatively infantile nature of environmental matters in the mainstream manufacturing and operations strategy research and argued for more studies in this area.Yet in October 2007, Rahimifard and Clegg (2007), in their editorial of the special issue on sustainable design and manufacture for the International Journal of Production Research, concluded that there is an urgent and imperative need for further research in every phase of a product’s life-cycle.There is little to indicate that the challenges particular to production operations are any exception. This situation is succinctly captured by Kleindorfer et al.(2005)when they argue that we must enlarge our perspective in operations management to include “the planet” because companieswill be expected to do so.The more mainstream operations management community still lacks, however, a cohesive understanding of green production.While those within the sustainability community may be fully conversant with the interpretations, ideas, and methods associated with Green, this is not necessarily the case with those practitioners and researchers from more mainstream production operations management.This therefore is the motivation behind our research.This paper sets out to review current literature, from a more conventional production operations perspective, and contributes a set of findings that capture the current state-of-the-art of this topic.In particular, it examines the evolution of green terminology, categorises green production types, and the role that green production can take in the competitive strategy of a manufacturer.This paper is structured to first present the literature review methodology that has been used, along with the research questions that have initially been used to guide the identification and analysis of articles. The findings from this review are then presented, discussed and conclusions drawn.

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An estimate of maintenance efficiency

An estimate of maintenance efficiency in Brown-Proschan imperfect repair model with bathtub failure intensity, The totality of the significant industrial systems is subjected to the actions corrective and preventive maintenance which are supposed to prolong their functional life. The efficiency evaluation of these maintenance actions is of a great practical interest, but it was seldom studied. In the literature, several models of maintenance effect were proposed. That is to say for example, Wang (2002)and Baxter, Kijimaand Tortorella (1996). The authors tried to classify various models of maintenance. Particularly, a very significant characteristic to consider is the evaluation of the system failure intensity, and primarilythe discovery at the appropriate time of its degradation. Moreover, to optimize the maintenance programs respecting the availability and to reduce the maintenance costs using the maintenance optimization by reliability (MOR), as it was the case in Jiang, Jiand Xia (2003) and Finkelstein (2008).More clearly, it is a question on the one hand of building stochastic models of failures process and repairs of various systems, and on the other hand, of implementing the statistical methods to exploit the failures and maintenances data raised by experts with an aim to evaluate the performance of these systemssuch as Doyen (2004).The majority of these models consider only the corrective maintenance (CM) effect, known under the name of repair models. These models are useful to model the real systems which are supported by a constant repair. Several repair models, including those of Brown-Proschan, the Block, Borgesand Savits model (1985), the Kijima model (1989), the most general models of Dorado, Hollanderand Sethuraman (1997) and Last-Szekli model (1998), were all useful in this respect. Several theoretical properties, as well as the parameters estimators of fundamental failure intensity and their asymptotic intervals confidence studiedby these authors, without evaluating the maintenance efficiency. The same claims of these models can be also used for the only preventive maintenance (PM).The idea of the Brown-Proschan model (1983) is that, the efficiency of the kthmaintenance action is evaluatedby a random variable Ek, independently and identically distributed according to the Bernoulli law with parameter p, such as:Knowing that maintenance is always minimal over all the improvement period and that of service life (i.e. for ). We can show that at the time tafter the duration passed since the last perfect maintenance (moreover, before the momentall maintenances are supposed to be minimal) can be expressed in the form: whererepresent the failures number (of maintenance action) will take place during, respectively the improvement and service life periods : i.e. before the instant . Under these conditions, the failure intensity is written by the sample principle given in the study of Dijoux (2009):Being given that the virtual age just after the kthmaintenance, noted ak,is equal to where the variableXhindicate thehthduration of the between-failures.Figure 1. Reformulation of the Brown-Proschan model intensityThe figure1 translated the trajectory of this intensity for an unspecified value of pbetween 0 and 1. In this figure, the instants of perfect and minimal maintenances are represented on the x-axis respectively by circles and squares.

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Fuzzy Shannon’s entropy

Integration of fuzzy Shannon’s entropy with fuzzy TOPSIS for industrial robotic system section, Recent developments in information technology and engineering sciences have been the main reason for the increased utilization of robots in a variety of advanced manufacturing facilities. Robots with vastly different capabilities and specifications are available for a wide range of applications (Rao, 2007). The selection of robots to suit a particular application and production environment from among the large number available in the market has become a difficult task. Various aspects such as product design, production system, and economics, need to be considered before a suitable robot can be selected. The selection problem is particularly relevant in view of the likely lack of experience of prospective users in employing a robot. Indeed, robots are still anew concept in industry as a whole, and so it is not unusual for an industry to be a first-time robot purchaser (Rao, 2007). Many precision-based methods for robot selection have been developed to date. Boubekri, Sahoui and Lakrib(1991) developed an expert system for industrial robot selection considering functional, organizational, and economical attributes in the selection process. Wang,Singh and Huang (1991) presented a decision support system that applies a fuzzy set method for robot selection. The objective attributes were evaluated via marginal value functions while the subjective attributes were evaluated via fuzzy set membership function. Data from both evaluations were finally processed such that a fuzzy set decision vector was obtained. However, the fuzzy method presented is a complicated one, and requires more computation. Booth, Khouja and Hu (1992) proposed a decision model for the robot selection problem using both Mahalanobis distance analysis, i.e., a multivariate distance measure, and principal-components analysis. Liang and Wang (1993) proposed a robot selection algorithm by combing the concepts of fuzzy set theory and hierarchical structure analysis. The algorithm was used to aggregate decision makers’ fuzzy assessments about robot selection attributes weightings, and to obtain fuzzy suitability indices. The suitability ratings were then ranked to select the most suitable robot. Khouja and Offodile (1994) reviewed the literature on industrial robots selection problems and provided directions for future research. Khouja (1995) presented a two-phase robot selection model that involved the application of data envelopment analysis (DEA) in the first phase, and a multi-attribute decision-making model in the second phase. The rest of the paper is organized as follows: The following section presents a concise treatment of the basic concepts of fuzzy set theory. Section 3 presents the methodology. The application of the proposed method is addressed in Section 4. Finally, conclusions are providedin Section 5.

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Arsitektur Firewall

Arsitektur Firewall

Arsitektur Firewall dapat dikonfigurasi dengan banyak cara, menggunakan komponen yang berbeda, mencapai tingkat keamanan yang berbeda dengan biaya pemasangan dan pemeliharaan yang berbeda. Keputusan ini akan tergantung pada kebutuhan dan evaluasi biaya / manfaat dari implementasi tersebut.

Gerbang level sirkuit dan aplikasi serta teknologi pemfilteran paket adalah komponen penting dari solusi firewall.

Pemfilteran paket memungkinkan Anda mengontrol lalu lintas jaringan secara efisien dan transparan. Dampak yang ditimbulkan oleh pengenalannya pada arsitektur jaringan adalah minimal, karena tidak memerlukan perubahan besar dalam konfigurasi perangkat jaringan. Mereka menawarkan perlindungan di tingkat transportasi dan jaringan.

Gerbang level sirkuit dan aplikasi memperluas perlindungan filter paket karena keduanya memiliki pengetahuan tentang protokol yang beroperasi pada lapisan transport, sehingga mereka dapat mengimplementasikan mekanisme pada level yang lebih terperinci.

Arsitektur utama dari pendekatan tepi dan beberapa variasinya ditampilkan di bawah ini:

Arsitektur pemfilteran router

Dalam konfigurasi ini, firewall terdiri dari satu router yang melakukan fungsi penyaringan paket. Ini adalah salah satu strategi termudah untuk diterapkan. Router memiliki dua antarmuka jaringan, satu terhubung ke jaringan internal dan yang lainnya terhubung ke jaringan eksternal. Ini memotong semua lalu lintas (masuk dan keluar) dan mengarahkannya ke penerima sesuai dengan aturan pemfilteran.

Host di jaringan internal berkomunikasi satu sama lain secara langsung, sedangkan komunikasi antara host di jaringan pribadi dan jaringan publik dibatasi pada paket yang diizinkan oleh router (sesuai dengan seperangkat aturan kontrol yang mencerminkan kebijakan keamanan).

Ini adalah pengaturan yang baik untuk garis pertahanan pertama firewall, tetapi untuk solusi yang pasti. Dalam konfigurasi ini, keamanan seluruh jaringan sepenuhnya bergantung pada aturan yang ditentukan di router. Jika penyerang berhasil memasuki sistem ini, dia akan memiliki akses ke seluruh jaringan internal. Juga, strategi ini membuat tidak mungkin untuk menyembunyikan alamat IP dari jaringan internal dan kemampuan pemantauan dan pencatatan tidak terlalu baik.

Arsitektur rumah ganda

Dalam arsitektur ini, firewall terdiri dari satu bastion host dual-home yang akan menerapkan pemfilteran jaringan dan aplikasi. Sistem ini memiliki dua antarmuka jaringan, di mana setiap antarmuka terhubung secara logis dan fisik ke segmen jaringan yang berbeda dan terpisah. Satu antarmuka jaringan terhubung ke jaringan eksternal yang tidak tepercaya (seperti Internet), yang lainnya terhubung ke jaringan pribadi.

Prinsip keamanan utama arsitektur ini adalah tidak mengizinkan lalu lintas jaringan dari jaringan eksternal untuk dirutekan langsung ke jaringan internal. Firewall harus, dalam semua kasus, bertindak sebagai perantara. Itulah sebabnya dalam sistem ini, fungsi perutean dinonaktifkan, sehingga host mengisolasi dua jaringan satu sama lain dengan memblokir semua paket IP yang ditangkapnya. Sistem yang terhubung ke setiap sisi host tidak dapat berkomunikasi secara langsung tetapi melalui host.

Ada dua cara di mana bastion host menyediakan layanan

Jika pengguna di jaringan lokal memiliki akun di bastion host, mereka mengizinkan mereka masuk untuk menggunakan layanan Internet. Aspek ini menghadirkan risiko keamanan yang serius karena perlindungan bergantung pada pengguna yang memilih kata sandi yang benar. Jika pengguna eksternal dapat masuk, mereka mendapatkan akses ke seluruh jaringan lokal.

Alternatifnya adalah tuan rumah menjalankan layanan proxy untuk setiap layanan yang ingin diizinkan, dengan cara ini pengguna bebas dari tanggung jawab atas keamanan jaringan.

Host ini dapat memberikan kontrol tingkat tinggi dengan mengizinkan host internal untuk berkomunikasi hanya dengan host ini. Host ganda rumah dapat menolak koneksi berdasarkan data yang dikandungnya. Meskipun banyak pekerjaan yang dibutuhkan untuk mencapai potensi penuh dari pengaturan ini.

Dalam arsitektur ini, perangkat ini sangat penting untuk keamanan jaringan, karena merupakan satu-satunya sistem yang dapat diakses (dan diserang) dari Internet, sehingga harus memiliki tingkat perlindungan yang tinggi tidak seperti kebanyakan sistem lainnya. host jaringan. intern. Karena itulah tuan rumah ini sering disebut bastion. Jumlah minimum perangkat lunak yang diperlukan harus diinstal pada host ini untuk mengurangi risiko gangguan.

Menerapkan layanan proxy menawarkan keunggulan dibandingkan pemfilteran paket, tetapi mungkin tidak tersedia untuk semua orang.

Arsitektur ini jauh lebih aman daripada yang sebelumnya, tetapi bahkan jika bastionnya rusak, seluruh jaringan lokal dibiarkan tidak terlindungi.

Arsitektur Host yang Diproyeksikan

Arsitektur Screened Host memiliki firewall yang terdiri dari router untuk packet filtering dan bastion host untuk menyaring koneksi di sirkuit dan level aplikasi. Garis perlindungan pertama yang sesuai dengan router dengan packet filtering, bastion host terhubung ke jaringan internal hanya sebagai host lain.

Router dikonfigurasi untuk mengatur semua lalu lintas yang datang dari jaringan eksternal ke bastion host, jadi ini adalah satu-satunya yang dapat diakses langsung dari luar jaringan lokal, oleh karena itu, bastion harus sangat dilindungi. Demikian juga, yang terakhir mengatakan semua lalu lintas yang datang dari jaringan internal ke router sehingga satu-satunya yang dapat membuat koneksi dengan luar. Selain itu, bastion hanya mengizinkan jenis koneksi dan protokol tertentu.

Router penyaringan paket dapat diatur dengan berbagai cara

Izinkan host internal tertentu untuk membuka koneksi Internet untuk layanan tertentu;

Nonaktifkan semua koneksi dari host internal dengan hanya mengaktifkan bastion host untuk membuat koneksi ini;

Mungkin juga beberapa paket dikirim, oleh router, langsung ke host internal.

Aspek-aspek ini bergantung pada kebijakan keamanan yang dipilih.

Berkat kemungkinannya, arsitektur ini lebih fleksibel dan memungkinkan beberapa layanan yang tidak didukung oleh proxy dapat dihubungi langsung oleh router ke host internal.

Ya, bastion memblokir semua lalu lintas antara jaringan eksternal dan jaringan lokal, ini disembunyikan dari host eksternal mana pun.

Seperti pada arsitektur sebelumnya, bastion mengelola koneksi melalui aplikasi proxy. Host di jaringan lokal dikonfigurasi untuk menangani semua permintaan ke server proxy, di bastion host, untuk berkomunikasi dengan jaringan eksternal.

Arsitektur ini lebih aman dan menambahkan lapisan keamanan ke arsitektur sebelumnya: penyerang harus melalui router terlebih dahulu dan kemudian melalui bastion host (tentu saja, ini selalu bergantung pada penggunaan kebijakan keamanan yang dirancang dengan benar).

Di sisi lain, arsitektur ini memiliki kelemahan: jika penyerang berhasil menerobos bastion host, mereka dapat memiliki akses ke seluruh jaringan internal.

Dalam model yang disajikan, bastion host terhubung ke jaringan sebagai host lain. Sebuah host dapat dikonfigurasi untuk terhubung ke router dan jaringan internal melalui antarmuka jaringan yang berbeda; ini menciptakan pembagian fisik antara jaringan internal dan router.
Arsitektur subnet yang difilter

Risiko yang ada di arsitektur sebelumnya dari bastion host yang dikompromikan dapat dikurangi dengan mengkonfigurasi jaringan perimeter yang terhubung dengannya. Jaringan ini sering disebut Zona Demiliterisasi.

Untuk mencapai arsitektur ini, router penyaringan paket diperkenalkan antara bastion host dan jaringan internal, sehingga bastion host akan berada di antara dua router (internal dan eksternal, satu antara jaringan perimeter dan jaringan eksternal dan yang lainnya. berada di antara jaringan perimeter dan jaringan internal) dan akan disambungkan ke segmen jaringan yang berbeda dari yang tersambung ke host jaringan pribadi. Dengan konfigurasi ini, tidak ada kerentanan yang mengganggu seluruh jaringan internal.

Dengan arsitektur ini, lapisan keamanan baru ditambahkan ke arsitektur sebelumnya yang mengisolasi jaringan lokal dari Internet. Dengan mengisolasi bastion host dalam jaringan perimeter, dampak serangan bastion tersebut dapat dikurangi.

Jika penyerang berhasil melewati perlindungan bastion host, mereka hanya dapat mengakses jaringan perimeter karena jaringan internal masih dilindungi oleh router internal. Dengan cara ini, penyerang hanya akan memiliki akses ke jaringan perimeter, menyembunyikan semua lalu lintas dari jaringan lokal.

Arsitektur ini adalah yang paling aman dari yang disajikan sejauh ini karena jaringan perimeter mendukung aspek keamanan di tingkat jaringan dan aplikasi, serta menyediakan tempat yang aman untuk menghubungkan server publik. Jaringan ini membentuk lapisan keamanan tambahan, antara jaringan eksternal dan jaringan internal yang dilindungi. Jika penyerang melanggar bastion host di jaringan perimeter, mereka hanya dapat melihat lalu lintas di jaringan tersebut. Semua lalu lintas di jaringan ini harus ke atau dari bastion host, atau ke dan dari jaringan eksternal. Karena lalu lintas jaringan internal melewati jaringan perimeter, Anda aman dari “diganggu” oleh penyusup, bahkan jika bastion host dikompromikan.

Router eksternal memberikan perlindungan terhadap serangan dari jaringan eksternal dan mengelola akses Internet ke jaringan perimeter. Dengan cara ini, ia melindungi jaringan perimeter dan jaringan internal.

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