The Mystery And Surprise Of Character Essay - 1426 Words

stories, would cease to exist and the tone of each story would not be near as terrifying as it is with the isolation playing a huge theme in Poe’s literature. Martin Luther King Jr. once said â€Å"The ultimate measure of a man is not where he stands in moments of comfort and convenience, but where he stands at times of challenge and controversy.† This quote could possibly be related to Poe’s characters in that their own character is measured on how they handle fear and terror. Harry Baker said of character and reactions to fear, â€Å"The mystery and surprise of character is in truth the great spectacle of this human life of ours...In a given set of circumstances, how will a certain individual (and no other) act?(Baker 143.) Poe brings his mystery into his stories by making his characters unpredictable with how they will handle their fear. The endings in each story are very much weighted by how how each character does respond to fear stimuli. Looking at The Te ll Tale Heart the narrator says, â€Å"In the quiet night, in the dark silence of the bedroom my anger became fear — for the heart was beating so loudly that I was sure someone must hear. The time had come! I rushed into the room, crying, â€Å"Die! Die!† The old man gave a loud cry of fear as I fell upon him and held the bedcovers tightly over his head. Still his heart was beating; but I smiled as I felt that success was near. For many minutes that heart continued to beat; but at last the beating stopped. The old man was dead. I tookShow MoreRelatedNotes On The Novel Fences And Pied Piper Of Tucson 1080 Words   |  5 PagesUnit 1 Guide Unit Learning Trajectory Students examine the ways in which mystery, tension, and surprise are used in informational and literary texts to engage and intrigue readers. 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Consider making the goal more specific and focus on one major patient. Create the story of the imaginary friend to be more compelling and mysterious. So, if the goal is to help Donald, make his story more captivating and stay focused on this story. Make it more suspenseful and peel away the mystery. Try to create a twist. Consider moving up what Slice says, â€Å"DeadRead MoreDiffferences in Detective Stories Essays824 Words   |  4 Pagesdamsel in distress even in detective stories. Whereas now in the remake of Sherlock Holmes the character played by Rachel McAdams has a huge role in helping solve cases. Another difference, although this depends on the writer, is at what point the actual murder takes place whether it is at the beginning of the story or the end. Edgar Allen Poe may have started off the detective story frenzy with his character Dupin but since then stories, roles of women and men, and how the stories are organized hasRead MoreThe Adventure Of The Speckled Band1307 Words   |  6 PagesNarrative discourse is made up of exposition/ setting, developing conflict, climax, final suspense, and conclusion. The narrative discourse is being portrait in the story by Sherlock trying to find the mystery. Helen Stoner goes to Sherlock Holmes and Dr. Watson for help on figuring out the mystery o f her sister’s death, and they both investigate. It all begins with the renovation that was done to the room. Holmes arrived to Dr. Grimesby Roylott’s home in order to investigate the noise that his daughterRead MoreGothic Literature : The Black Cat1161 Words   |  5 Pagessituation of punished to death. This literature piece definitely belongs to the Gothic genre. 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Pharmaceutical Services and Health Promotion

Question: Discuss about the Pharmaceutical Services and Health Promotion. Answer: Introduction: Health- promotion that involves supporting the individuals to impose control over as well as to improve their health is vital in todays world. The 1st health conference, Ottawa Charter for health promotion has clarified the fundamental concepts and aspects in regard to health- promotion, which is the responsibility of various sectors (including pharmacology scientists) that goes beyond health with necessity to progress beyond the healthy life- style especially to achieve a global well- being (Catford, 2011). In regard to pharmaceutical context, after Ottawa charter conference, various international practices, procedures and policies and pharmacological researches has started taking health- promotion as one among the objectives of pharmacists as well as pharmacists' practice. It is clear that the pharmaceutical field has tended to come close to health- care with public- health from 1980s by relating pharmacists and pharmacology scientists to provide medications and to educate about ri sk reduction and lifestyle changes. This essay discusses about the areas of OC and its relevance to pharmacology scientists. The first area of OC is building healthy- public policies that involves taking coordinated action to address health equity and assuring safer as well as healthier goods with services along with healthy-public services (Nakamura, 2014). It means that all the goods including medicines should be well researched so as to provide safe, effective and harmless medications to people that ensures the provision of healthier services to people in an enjoyable environment. Moreover, this areas of action is indented to include health in its agenda by the policy- makers in all sectors with all levels and directing them to understand the health consequences and accept their responsibilities. Hence, this area is highly relevant for our profession. The second area of creating supportive environments involves promoting health to enhance safe, stimulating, well satisfactory with enjoying life and working environment. It is not relevant to pharmacology scientists profession as this area deals with the actions of only pharmacist who takes the last position in the patients' contact chain after being diagnosed by health-care personnel to make decisions about pharmacological therapy (Kellow, 2011) or sometimes being the sole contact for drugs that may not require a medical- prescription or may be for changes in life-style as to quit smoke, stop alcohol abuse, etc (Aquilino, 2003). This area doesnt deal with the role of pharmacology scientists. The next area of strengthening community actions involves educating and counseling the people about the drugs dosage, adverse effects with drug interactions and about changes in life-style as nutritional counseling, physical therapy and quitting smoking (Lenz, 2011). This area is not relevant to my profession as it deals with only education and counseling aspects. As per next area, professionals should develop personal skills to promote health in community. Similarly, pharmacology scientists should conduct research and develop their personal skills to promote communitys health. They identify and select the persons with risk- factors for disease that are targeted in national health-care programs (cardio-vascular diseases) and analyze the effect of medication therapy that is required to prevent, treat or control the disease by their researches. Hence, this area is highly relevant to my profession. The next area of re-orienting to health services that involves re-organizing the pharmaci es by conducting researches and to modify goods and services based on current needs is practiced by pharmacology scientist. Hence, this area is relevant to my profession. Hence, among five areas of Ottawa Charter, three areas are relevant to pharmacology- scientists profession. Reference Aquilino, M.L. (2003). Smoking-cessation services in Iowa community pharmacies: Pharmacotherapy. 23(5): 666-673. Catford, J. (2011). Ottawa 1986: back to the future: Health Promot. Int. 26(2): ii163-ii167. Kellow, N. (2011). Evaluation of a rural community pharmacy-based Waist Management Project: bringing the program to the people: Aust. J. Prim. Health. 17(1):16-22. Lenz, D. (2011). Evaluation of the use of topic nasal decongestants in university students from health sciences courses: Braz. J. Pharm. Sci. 47(4): 761-767. Nakamura, C.A. (2014). Pharmaceutical services and health promotion: how far have we gone and how are we faring? Scientific output in pharmaceutical studies: Brazilian Journal of Pharmaceutical Sciences. 50(4). Retrieved from https://www.scielo.br/scielo.php?script=sci_arttextpid=S1984-82502014000400773

Smart socket Essay Example

Smart socket Essay Although ad-hoc solutions exist for some of these problems, it is usually up to the applications user to discover the cause of the connectivity problems and find a solution. In this paper we describe Smokestacks, a communication library that lifts this burden by automatically discovering the connectivity problems and solving them with as little support from the user as possible. Categories and Subject Descriptors: C. 2. 4 [Distributed Systems]: Distributed applications General Terms: Algorithms, Design, Reliability Keywords: Connectivity Problems, Grids, Networking, Parallel Applications 1 . Parallel applications are increasingly run in Grid environments. Unfortunately, on many Grid sites the ability of machines to create or accept network connections is severely limited by network address translation (NAT) [14, 26] or firewalls [15]. There are even sites that completely disallow any direct communication between the compute nodes and the rest of the world (e. G. , the French Grinding system [3]). In addition, multi homing (machines with multiple network addresses) can further complicate connection setup. We will write a custom essay sample on Smart socket specifically for you for only $16.38 $13.9/page Order now We will write a custom essay sample on Smart socket specifically for you FOR ONLY $16.38 $13.9/page Hire Writer We will write a custom essay sample on Smart socket specifically for you FOR ONLY $16.38 $13.9/page Hire Writer For parallel applications that require direct communication between their components, these limitations have hampered the transition from traditional multi receptors or cluster systems to Grids. When a combination of Grid sites is used, serious connectivity problems are often encountered. Smokestacks is part of the Ibis project, and can be found at http://www. CSS. Vi. Ml/ibis Permission to make digital or hard copies of all or part of this work for personal or classroom use is granted without fee provided that copies are not made or the full citation on the first page. Many problems, however, can only be solved by adapting the application or the communication library it uses. To make matters worse, as soon as the set of Grid systems being used changes, large part of this process needs to be repeated. As a result, running a parallel application on multiple Grid sites can be a strenuous task [34]. In this paper we will describe a solution to this problem: the Smokestacks communication library. The primary focus of Smokestacks is on ease of use. It automatically discovers a wide range of connectivity problems and attempts to solve them with little or no support from the user. Smokestacks combines many known solutions, such as port forwarding, TCP splicing and SSH tunneling, and introduces several new ones that resolve problems with multi homing and machine identification. In 30 connection setup experiments, using 6 different sites worldwide, Smokestacks was always able to establish a connection, while conventional sockets only worked in 6 experiments. Using heuristics and caching, Smokestacks is able to significantly improve the connection setup performance. Smokestacks offers a single integrated solution that hides the complexity of connection setup in Grids behind a simple interface that closely resembles sockets. We will show that it is relatively straightforward to port an existing application to Smokestacks, provided that certain programming guidelines are followed. Smokestacks is not specifically intended for use in parallel applications or Grids. It can also be applied to other distributed applications, such as visualization, cooperative environments, or even consumer applications such as instant messaging, file sharing, or online gaming. However, many of these applications only require a very limited degree of connectivity. Often, clients simply connect to a server in a well-known location, making it relatively easy to apply an ad-hoc solution when a connectivity problem occurs. Parallel applications, however, can be much more challenging. They often require a large number of connections between the participating machines, and each machine must such applications in a Grid environment with limited connectivity is difficult. Therefore, this paper will focus on this domain. N Section 2 we describe the connectivity related problems encountered while running applications on multiple Grid sites. Section 3 describes how these problems are solved in Smokestacks and briefly looks at the programming interface. Section 4 evaluates the performance of Smokestacks, Section 5 describes related work, and Section 6 concludes. 2. CONNECTIVITY PROBLEMS In this section we will give a description of the network related problems that can occur when running a single parallel or distributed application on multiple Grid sites. . 1 Firewalls As described in [1 5], A firewall is an agent which screens network traffic in some way, blocking traffic it believes to be inappropriate, dangerous, or both. . Many sites use firewalls to protect their network from unauthorized access. Firewalls usually allow outbound connections, but block incoming connections, often with the exception of a few welkin ports (e. G. , port 22 for SSH). It is obvious that this inactivity restriction can cause severe problems when running a parallel application on multiple sites. When only a single participating site uses firewall, the connectivity problems can sometimes be solved by ensuring that the connections setups are in the right direction, I. E. , that all required connections between open and firewall machines are initiated at the firewall site. This solution may require changes to the applications or communication libraries, however. Also, if both sites use a firewall, this approach can no longer be used. In this case, a firewall will always be encountered regardless of he connection setup direction. One way to solve the problems is to request an open port range in the firewall. Connectivity can then be restored by adapting the application to only use ports in this range. Besides requiring reconfiguration of the firewall, open ports are also seen as a threat to site security. When both machines are behind a firewall it may still be possible to establish a direct connection using a mechanism called TCP splicing [6, 10, 13, 20]. Simply put, this mechanism works by simultaneously performing a connection setup from both sides. Since this approach requires explicit cooperation teens the machines, some alternative communication channel must be available. . 2 Network Address Translation As described in [21], Network Address Translation is a method by which IP addresses are mapped from one address realm to another, providing transparent routing to end hosts. . NAT was introduced in [12] as a temporary solution to the problem of IPPP address depletion. Although the intended solution for this problem, IPPP, has been available for some time, NAT is still widely used to day. Frequently used [21, 29]. This type of NAT allows outbound connections from sites using riveter addresses, but does not allow incoming connections. Both the IP address (and related fields) and the transport identifier (e. G. , TCP and JODI port numbers) of packets are translated, thereby preventing port number collisions when a set of hosts share a single external address. As mentioned above, NAT only allows outbound network connections. Incoming connections are rejected, since the connection request does not contain enough information to find the destination machine (I. E. , only the external IP address is provided, but that may be shared by many machines). This restriction leads to connectivity problems hat are very similar to those caused by firewalls. Therefore, the solution described in Section 2. 1 (connecting in the right direction) also applies too NAT setup, and fails in a similar way when multiple NAT sites try to interconnect. Although the TCP splicing mechanism can also be used to connect two NAT sites, a more complex algorithm is required to compensate for the port translation performed by NAT [6, 20]. Some NAT implementations have support for port forwarding, where all incoming connections on a certain port can be automatically forwarded to a certain host inside the NAT site. Using mechanisms such as Upon [5], DIF [28], or MEDICO [30], applications can contact the NAT implementation and change the port forwarding rules on demand. Port forwarding lifts many of the restrictions on incoming connections. Unfortunately, Upon is mostly found in consumer devices, MEDICO is still under development, and DIF only supports NAT (and firewall) implementations based on Interfile [1]. As a result, these mechanisms are not (yet) generally usable in Grid applications. Currently, Smokestacks only supports Upon. In addition to causing connection setup problems, NAT also complicates machine identification. Machines in a NAT tit generally use IP addresses in the private range [26]. These addresses are only usable within a local network and are not globally unique. Unfortunately, parallel applications often use a machines IP address to create a unique identifier for that machine. When multiple NAT sites participate in a single parallel run, however, this approach can not be used, since the machine addresses are no longer guaranteed to be unique. 2. 3 Non-routed networks On some sites no direct communication between the compute nodes and the outside world is possible due to a strict separation between the internal and external networks. No aching is accessible, and the connectivity of this machine may be limited by a firewall or NAT. Two of the sites used in Section 4 use such a setup. It is clear that this is a major limitation when the site is used in a parallel application. The only possibility for the compute nodes to communicate with other sites is to use front-end machine as a bridge to the outside world, using, for example, an SSH tunnel or a SOCKS [24] proxy. These are non-trivial to set up, however. 2. 4 Multi Homing When multi-homed machines (I. E. , machines with multiple network addresses) participate in a parallel application, another interesting problem occurs. When creating a connection to such a machine, a choice must be made on which of the possible target addresses to use. The outcome of this choice may depend on the location of the machine that initiates the connection. For example, the front-end machine of a site has two addresses, a public one, reachable over the internet, and a private one used to communicate with the sites compute nodes. As a result, a different address must be used to reach teachings depending on whether the connection originates inside or outside of the site. In [34] we called this the Reverse Routing Problem. Normally, when a multi-homed machine is trying to connect to a single IP address, a routing table on the machine decides which network is used for the outgoing connection. In the example described above the reverse problem is encountered. Instead of having to decide how to exit a multi-homed machine, we must decide on how to enter it. This problem is non-trivial, since the source machine generally does not have enough information available to select the correct target address. As a result, several connection attempts to different addresses of the target may be necessary before a connection can be established. In Section 3. 2 we will describe heuristics that can be used to speed up this process. Multi homing can have a major effect on the implementation of parallel programming libraries. The example above shows that it is not sufficient to use a single address to represent a multi-homed machine. Instead, all addresses must be made available to the other participants of the parallel application. In addition, some of the addresses may be in a private range and refer to a different machine when used in a different site. Therefore, it is also essential to check if a connection was established to the correct machine. 3. SMOKESTACKS In this section we will give an overview of the design, implementation and programming interface of the Smokestacks library, and describe how it solves the problems described in the previous section. 3. 1 Overview Currently, Smokestacks offers four different connection setup mechanisms, Direct, Reverse, Splicing, and Routed. An overview of how these mechanisms solve the connectivity problems described in Section 2. As the table shows, each problem is solved by at least one mechanism. Table 1 : Overview of connectivity problems and their solutions. Connection Setup Mechanism Problems Direct Reverse Splicing Routed Identification X Multi Homing X Single FEW/NAT pox xx Dual MINOT (X) XX No Routing X The machine identification and multi-homing problems are solved by the direct connection setup. As will be explained below, this approach also has limited firewall traversal capabilities (using SSH tunneling), so in certain situations it may succeed in establishing a connection in a single or even a dual firewall setting. In the table these entries are shown between brackets. A reverse connection setup is only capable of creating a connection when a single firewall or NAT limits the connectivity. Splicing is capable of middling both single and dual firewall/NAT configurations. However, this approach is significantly more complex than a reverse connection setup (especially with dual NAT) and may not always succeed. Therefore, reverse connection setup is preferred for single firewall/NAT configurations. A routed connection setup can be used in any situation where the connectivity is limited. Unlike the previous two approaches it does not result in a direct connection. Instead all network traffic is routed via external processes called hubs (explained in Section 3. 3), which may degrade both latency and throughput of the connection. Therefore, the previous mechanisms are preferred. When connecting to or from a machine on a non-routed network, however, a routed connection is the only choice. The Smokestacks implementation is divided into two layers, a low-level Direct Connection Layer, responsible for all actions that can be initiated on a single machine, and a high-level Virtual Connection Layer that uses side-channel communication to implement actions that require cooperation of multiple machines. The direct connection layer is implemented using the standard socket library. The virtual connection layer is implemented using the direct connection layer. Both layers will be explained in more detail below. Currently, Smokestacks is implemented using Java [2]. 3. 2 Direct Connection Layer do not require explicit cooperation between machines, such as determining the local addresses or creating a direct connection. It also supports a limited form of SSH tunneling. 3. 2. 1 Machine Identification During initialization, the direct connection layer starts by scanning all available network interfaces to determine which IP addresses are available to the machine. It then generates a unique machine identifier that contains these addresses, and that can be used to contact the machine. This identifier will automatically be unique if it contains at least one public address. If all addresses are private, however, additional work must be done. A machine that only has private addresses is either in a NAT site or uses a non-routed network. In the first case, a unique identifier can still be generated for the machine by acquiring the external address of the NAT. Provided that this address is public, the combination of external and machine addresses should also be unique, since other machines in the same NAT site should have a different set of private addresses, and all other NAT sites should have different external address. The Smokestacks library will use Upon to discover the external address of the NAT site. If this discovery fails, or if the returned address is not public, a Universally Unique Identifier (JUDI) [23], will be generated and included in the machine identifier, thereby making it unique. 3. 2. 2 Connection Setup Once initialized, the direct connection layer can be used to set up connections to other machines. The identifier of the target machine may contain multiple network addresses, some of which may not be reachable from the current location. The private dresses in the identifier may even refer to a completely different machine, so it is important that the identity of the machine is checked during connection setup. As a result, several connection attempts may be necessary before the correct connection can be established. When multiple target addresses are available, a choice must be made in which order the connection attempts will be performed. Although simply using the addresses in an arbitrary order should always result in a connection (pro-vided that a direct connection is possible), this may not be the most efficient approach. Many Grid sites offer historiographer networks such as Merriment [7] or Infinite [4] in addition to a regular Ethernet network. Using such a network for inter-site communication may significantly improve the applications performance. In general, these fast networks are not routed and use addresses in the private range, while the regular Ethernet networks (often) use public addresses. Therefore, by sorting the target addresses and trying all private ones first, the fast local networks will automatically be selected in sites with such a setup. The drawback of if the connection originates on a different site. This may cause a significant overhead. Therefore, Smokestacks uses a heuristic that sorts the target addresses in relation to the addresses that are available locally. For example, if only a public address is available on the local machine, it is unlikely that it will be able to create a direct connection to a private address of a target. As a result, the connection order public before private is used. This order is also used if both machines have public and private addresses, but the private addresses refer to a different network (e. G. , 10. 0. 0. 10 vs 192. 168. 1. 20). The order private before public is only used if both machines have private addresses in the same range. Section 4 will illustrate the performance benefits of this heuristic. Unfortunately, it is impossible to make a distinction between addresses of the same class. For example, if a target has multiple private addresses, we can not automatically determine which address is best. Therefore, if a certain network is preferred, the user must specify this explicitly. Without this explicit configuration, Smokestacks will still create a direct connection (if possible), and the parallel application will run, but its performance may be suboptimal. When a connection has been established, an identity check s performed to ensure that the correct machine has been reached. This would be a simple comparison if the complete identifier of the target is available, but unfortunately this is not always the case. User provided addresses are often used to bootstrap a parallel application. These addresses are often limited to a single hosannas or IP address, which may only be part of the addresses available to the target machine. Therefore, the identity check used by Smokestacks also allows the use of partial identifiers. Whenever a connection is created, the target machine provides its complete identity o the machine initiating the connection. This machine then checks if both the public and private addresses in the partial identity are a subset of the ones in the complete identity. If so, the partial identity is accepted as a subset of the complete identity, and the connection is established. Note that although the connection is created to a machine that matches the address specified by the user, it is not necessarily the correct machine from the viewpoint of the parallel application. Unfortunately, in such cases it is up to the user to provide an address that contains enough information to reach the correct machine. . 2. 3 Open Port Ranges and Port Forwarding When a firewall has an open port range available, Smokestacks can ensure that all sockets used for incoming connections are bound to a port in this range. There is no way of discovering this range automatically, however, so it must be specified explicitly by the user. In addition, Smokestacks can use the Upon protocol to configure a NAT to do port forwarding, I. E. Automatically forward all incoming connections on a certain external port to a specified internal address. However, as explained before, this protocol is mainly used in consumer devices. In addition to regular network connections, the direct connection layer also has limited support for SSH tunneling. This feature is useful for connecting to machines behind a firewall that allows SSH connections to pass through. It does, however, require a suitabl e SSH setup (I. E. , public key authentication must be enabled). Creating an SSH tunnel is similar to a regular connection setup. The target addresses are sorted and tried consecutively. Instead of using the port specified in the connection setup, however, the default SSH port (I. E. , 22) is used. When a connection is established and the authentication is successful, the receiving SSH daemon is instructed to forward all traffic to the original destination port on the same machine. If this succeeds, the regular identity check will be performed to ensure that the right machine has been reached. Although this approach is useful, it can only be used to set up a tunnel to a different process on the target machine. Using this approach to forward traffic to different machines requires extra information. For example, setting up an SSH tunnel to a compute node of a site through the sites fronted, can only be done if it is clear that the fronted must be contacted in order to reach the target machine. Although this approach is used in some projects [8], the necessary information cannot be obtained automatically and must be provided by the user. Therefore, Smokestacks uses a different approach which will be described in detail in Section 3. 3. 3. 2. Limitations The direct connection layer offers several types of connection setup which have in common that they can be initiated by a single machine. No explicit cooperation between machines is necessary to establish the connection. There are many cases, however, where connectivity is too limited and the direct connection layer cannot be used. In general, direct connections to sites that use NAT or a firewall are not possible. Although SSH tunneling and o pen port ranges alleviate the firewall problems, they require a suitable SSH setup or extra information from the user. Port forwarding reduces the problems with NAT, but is rarely supported in Grid systems. Therefore, these features are of limited use. In the next section we will give a detailed description of the virtual connection layer, which solves these problems. 3. 3 Virtual Connection Layer Like the direct connection layer, the virtual connection layer implements several types of connection setup. It offers a simple, socket-like API and has a modular design, making it easy to extend. Besides a direct module that uses the direct connection layer described above, it contains several modules that offer more advanced types of connection setup. These modules have in common that they cooperation (and thus communication) between the source and target machines in order to establish a connection. As a result, side-channel communication is required to implement these modules. 3. 3. 1 Side-Channel Communication In Smokestacks, side-channel communication is implemented by creating a network f interconnected processes called hubs. These hubs are typically started on the fronted machines of each participating site, so their number is usually small. When a hub is started, the location of one or more other hubs must be provided. Each hub will attempt to setup a connection to the others using the direct connection layer. Although many of these connections may fail to be established, this is not a problem as long as a spanning tree is created that connects all hubs. The hubs use a gossiping protocol to exchange information about themselves and the hubs they know, with the hubs that they are connected to. This way information about each hub quickly spreads to all hubs in the network. Whenever a hub receives information about a hub it has not seen before, it will attempt to set up a connection to this hub. This way, new connections will be discovered automatically. All gossiped information contains a state number indicating the state of the originating machine when the information was sent. Since information from a hub may reach another hub through multiple paths, the state number allows the receiver to decide which information is most recent. By recording the length of the path traversed thus far in he gossiped information, hubs can determine the distance to the sites that they can not reach directly. Whenever a hub receives a piece of information about another hub containing a shorter distance than it has seen so far, it will remember both the distance and the hub from which the information was obtained. This way, we automatically create a distributed routing table with the shortest paths between each pair of hubs. This table is later used to forward application information (as will be described below). When an application is started, the virtual layer on each machine creates a single connection to the hub local to its tit. The location of this hub can either be explicitly species- fled or discovered automatically using JODI multicast. 3. 3. 2 Virtual Addresses The connection to the hub can now be used as a side channel to forward requests to otherwise unreachable machines. To ensure that the target machines can be found, addresses are used, consisting of the machine identifier (see Section 3. 2), a port number, and the identifier of the hub the machine is connected to. All requests for the target machine can then be sent to the local hub, which forwards it in the direction of the target

Example Sentences of the Verb Eat for ESL Learners

Example Sentences of the Verb Eat for ESL Learners This page provides example sentences of the verb eat in all tenses including active and passive forms, as well as conditional and modal forms. Base Form eatPast Simple atePast Participle eatenGerund eating Present Simple I usually eat at six oclock. Present Simple Passive Dinner is usually eaten at six oclock. Present Continuous We are having dinner at six this evening. Present Continuous Passive Dinner is being eaten at six this evening. Present Perfect He has already eaten. Present Perfect Passive Dinner hasnt been finished yet. Present Perfect Continuous We have been eating for two hours! Past Simple Jack ate a great lunch at Marcos Restaurant. Past Simple Passive A great lunch was eaten at Marcos Restaurant. Past Continuous We were eating lunch when she burst into the dining room. Past Continuous Passive Lunch was being eaten when she burst into the dining room. Past Perfect He had already eaten lunch when we arrived. Past Perfect Passive Lunch had already been eaten when we arrived. Past Perfect Continuous They had been eating for two hours when he got home. Future (will) They will eat lunch at work. Future (will) passive Lunch will be eaten in a restaurant. Future (going to) We are going to eat dinner at home this evening. Future (going to) passive Dinner will be eaten at home this evening. Future Continuous We will be eating French food this time next week. Future Perfect They will have eaten dinner by the time we arrive. Future Possibility The might eat in a restaurant. Real Conditional If she eats before she leaves, well have lunch alone. Unreal Conditional If she ate more, she wouldnt be so skinny! Past Unreal Conditional If she had eaten more, she wouldnt have become ill. Present Modal You should eat more spinach! Past Modal He might have eaten before he left. Quiz: Conjugate With Eat Use the verb to eat to conjugate the following sentences. Quiz answers are below. In some cases, more than one answer may be correct. I usually _____ at six oclock.He _____ already _____ lunch when we arrived.We _____ lunch when she burst into the dining room.We _____ dinner at home this evening.They _____ dinner by the time we arrive.If she _____ more, she wouldnt be so skinny!Jack _____ a great lunch at Marcos Restaurant.A great lunch _____ at Marcos Restaurant yesterday.We _____ dinner at home this evening.He _____ already _____.Dinner _____ at six this evening. Quiz Answers eathad eatenwere eatingare going to eatwill have eatenatewas eatenare going to eathas eatenis being eaten

What user's want from mobile location-based advertising services Literature review

What user's want from mobile location-based advertising services - Literature review Example It is important for businesses to identify a customer in close proximity to their premises, hence offering them incentives that enable them to identify the selected shops. Tsai et al. (2009) concur with the fact that location awareness brings an interesting aspect to customers since the majority of their purchase decisions are usually made within stores. The finding is in line with the idea that location-based adverts address consumers at the point of purchase decisions while at the same time holding potential results for entrepreneurs. Moreover, there are possibilities of integrating personalised offers and advertisements within the applications (Mobile Marketing Association, 2011). However, this study reviews numerous studies and models that focus on detailed variables influencing consumers’ intention towards mobile location-based advertising services. According to Ickin et al., (2012) the introduction of smart phones with GPS receivers has made marketers to be vigilant on the use of technology. In this case, marketers utilise locations to target customers sending them messages on company location alongside products and services offered. Improvement in technology drives the capabilities of Location Based Advertising granting marketers opportunity of creating clever techniques of selling their brands to customers. However, consumers are trying to gain composure on the idea that advertisers are able to locate them, implementation of such services as Foursquare focuses on delivering large consumer base for band advertisers. On the other, hand Wac et al. (2011) assert that some of the new technology initiatives, business models alongside willingness of consumers to accept the technology make mobile location one of the important elements of marketing. The failure associated with many location initiatives results from most marketers ign oring the actual consumer wants. One of the most important considerations is ensuring that services utilizing

Maritime law Essay Example | Topics and Well Written Essays - 1750 words

Maritime law - Essay Example The law of maritime claims has been promoted along different routes in civil law administration. Vessels are recognised as objects of security rights in all nations. Despite this and the fact that maritime claims are of profound commercial significance, there is a high degree of international uncertainty in the subject of maritime claims and mortgages. There is a great difference among nations in the way they create and enforce maritime claims. It is for this reason that a standard list of maritime claims and an agreeable way of enforcing them was drafted by Comire Maritime International and adopted by the Brussels Diplomatic Conference. In 1926 in Brussels, the initial efforts were made to unify particular rules regarding maritime claims and mortgages. However, there were problems in the enforcement of the rules and this led to a review in 1952 in Brussels, undertaken by IMO and UNCTAD. The international convention on the arrest of ships was the combined efforts of the numerous conventions held earlier, especially the 1952 international convention, which aimed at unifying certain rules adopted by various countries in relation to arrest of sea going ships. At Geneva in March 1999, the new international convention on the arrest of ships as expressed in A/CONF.188/6 was adopted by the conference, after reviewing the 1952 arrest convention to address the identified deficiencies. As a result, the categories of maritime claim that could lead to arrest were altered, changing from 17 in 1952 convention to 22 in the 1999 convention. Not many countries have been able to approve the new convection, so it may apply in their countries., because some nations still feel dissatisfied by the new rule and its consequences it could cause in the nations. After Albania, which was the 10th country to ratify the new convention in March 2011, the new international convention came into forc e on 14th September 2011, and was to apply to any ship within the signatory state’s jurisdiction.3 The number of ratifying countries is still low and one would question the reason for the reluctance; it is worth noting that most of the powerful nations, such as the US, UK, and Japan have not attempted to approve it. However, by properly analyzing the 1999 arrest convention and its implications, there are both benefits and negative effects in the society. Effects of the New Convention 1. Liability for unjustified arrests or excessive security Following the inclusion of damages costs in the 1999 convention, which was not part of 1952 convention, the owners of the arrested ships are further protected by the legal terms in case of incurred loss, found to have been attributed to the claimant arrest directive. According to Article 6 of A/CONF.188/6, the court could impose upon the claimant the obligation to provide certain security, upon such terms as could be determined in court f or any loss the defendant acquires from the unjustified/wrongful arrest, or demanded excessive security in which the claimant may be found liable.4 With this part of the law, there are chances that the shipping industry may view the article differently. ‘The states with flags of convenience and states with large fleets could try to limit the cases where arrest may be made and thus ratify the 1999 convention, whereas states having a dominant trading economy might request security for what could happen to their cargo and their contracts of carriage vital for import and export.’5 While some countries could limit the cases of arrest within their jurisdiction for fear of defendants claim for damage, others could increase chances of security claim for their benefit. This move extends to cause more costs in solving for the cases that will occur in future, due to broadened scope of arrests considering that no party so desires to spend their

College Goals Essay Example for Free

College Goals Essay Attending college is the first step to a better future. Throughout life there will be many goals to accomplish but some of the most important goals to accomplish will be during the time you are in college. My first goal is to pass every class this semester. After completing this goal my next goal to complete will be to graduate from Hudson County Community College with an Associate’s Degree in Liberal Arts. Finally my last goal to complete is to further my education and get the job I want. Passing every class this semester will help me feel positive and confident about my future and future goals. In order to complete this goal I will have to attend every class and be on time. By missing one class I will miss out on a lot of work and may not be able to catch up. I will have to finish every assignment on time because if I write the best essay I could possibly write but hand it in late, my grade will drop dramatically. Finally I will have to ask for help if I need it. Even though it is my first semester of college and I do not know what to expect, asking for help is easy and can help improve my college experience. To be able to obtain my Associate’s Degree in Liberal Arts by August 2015 I will have to work harder than I ever have. I will have to be sure to complete all my assignments and be sure to attend all my classes. I will have to put school first in life and avoid activities that will have a negative impact on my education. Prior to achieving this goal I also want to choose the career I want so I can know what direction my life is going. My final long-term college goal is to go on to obtain my Bachelor’s Degree and possibly my Master’s Degree, depending on the career I choose. I have not chosen the career I want yet but I want to have the best education possible to qualify me for the job. To be able to obtain the best education possible I want to keep my grade point average high and be able to attend a good university. I have not really thought about all the details since I have not chosen a career yet but I am going to better my education as much as I possibly can. After completing all my education I will have the job I want and be happy and financially stable. In conclusion, my college goals are some of the most important in my life because they greatly help shape my future. By passing all my classes this semester I will have the confidence to continue my education and do well. By obtaining my Associate’s Degree I will be able to go on and obtain my Bachelor’s and possibly Master’s Degrees. And finally when I finish completing all my education I will be able to get the career I want and be happy with my life. My entire future depends on the choices I make in college.