当前位置：文档之家 › Three years operation experience of a ground source heat pump system in Northern Greece

Three years operation experience of a ground source heat pump system in Northern Greece

  • 格式：pdf
  • 大小：879.84 KB
  • 文档页数：7

Three-years operation experience of a ground sourceheat pump system in Northern GreeceA.Michopoulos,D.Bozis,P.Kikidis,K.Papakostas,N.A.Kyriakis*Process Equipment Design Laboratory,Department of Mechanical Engineering,Aristotle University of Thessaloniki,P.O.Box487,54124Thessaloniki,GreeceReceived16May2006;received in revised form1August2006;accepted4August2006AbstractThe paper presents the basic parameters and the energyflows of a ground source heat pump system(GSHP)used for air conditioning the New City Hall of Pylaia(Thessaloniki area—Northern Greece).The building is a typical public one,with an air-conditioned area of1350m2.The ground source heat pump installation is the largest in Greece,and its operation is monitored with the aid of a DAQ system.The energyflows presented in the paper are based on DAQ recordings of thefirst3years of system’s operation.It is proved that the energy demand of the system is significantly lower,compared to that of conventional heating and cooling systems.The seasonal COP of the system has not yet been stabilized, gradually increasing,as it is expected due to the operation of the ground heat exchanger.#2006Elsevier B.V.All rights reserved.Keywords:Ground source heat pump system(GSHP);Energy demand;Heating loads;Cooling loads1.IntroductionHeat pumps are characterized by the strong dependency of their coefficient of performance(COP)on primary circuit temperature.Consequently,‘‘pumping’’heat from a very low (e.g.around freezing or below)temperature heat reservoir or rejecting heat to a high temperature(408C or higher)heat reservoir make the system inefficient in terms of primary energy(electricity)demand.This characteristic implies that the ambient air,depending on climate conditions,may not be the best choice for primary circuit heat reservoir.The use of surface or underground water reservoirs orflows in water-to-air or water-to-water systems overcomes this disadvantage,but again such reservoirs orflows are not widely available.Due to the heat capacity of soil,ambient air temperature variations are directly reflected only on the surface soil temperature,their effect being reduced at deeper layers.As a consequence,soil temperature is stabilized at the yearly average air temperature after the depth of about10m[1].A ground heat exchanger can therefore be formulated,supplying the primary circuit of the heat pump with afluid of a more or less constant temperature.A number of ground heat exchanger concepts(vertical, horizontal,of in series or in parallel connection,etc.)have been developed,featuring different degrees offluid temperature stability[2–4].In this work,a vertical ground heat exchanger of parallel connection coupled to a heat pump system for air conditioning a public building in northern Greece is presented with energy data regarding its operation over3years.2.Description of the building and installationThe ground source heat pump system is installed at the New City Hall of Pylaia,a suburban of Thessaloniki,in Northern Greece.The building was designed in1995and the construction works were completed in2002.It is located at a distance of8km from Thessaloniki centre,in an area with basic climate parameters as listed in Table1.These parameters, combined with the shape and orientation of the building,may impose simultaneous heating and cooling of different thermal zones,especially during intermediate seasons(autumn and spring).The building houses the Administration Services of the Pylaia Municipality,and it consists of two underground and/locate/enbuildEnergy and Buildings39(2007)328–334*Corresponding author.Tel.:+302310996083;fax:+302310996087.E-mail address:nkyr@auth.gr(N.A.Kyriakis).0378-7788/$–see front matter#2006Elsevier B.V.All rights reserved.doi:10.1016/j.enbuild.2006.08.002three over groundfloors.The main functions of the building (offices,meeting rooms,a200people auditorium and corridors) are located at the three over groundfloors,covering a total air-conditioned area of1350m2.Auxiliaries(store rooms,record rooms,utilities and car parking)cover a ventilated area of 1070m2and they are located at the two underground levels.On average,the building is in operation250days per year,from 08:00until18:00.During the design phase,the total heating load of the building was calculated at150kW,with60%of it being ventilation losses.The total cooling load was calculated at 270kW,appearing at the time slot15:00–17:00in July.The observed significant difference between heating and cooling loads is mainly due to the high solar loads,and it is typical for office buildings in Greece,even in the northern part of the country.The offices and the corridors are air-conditioned with two pipe fan-coil units.In terms of their connection to the hot or chilled water loops,the fan-coils were organized in four groups, based on the operation and the thermal characteristics of the room they serve.As a result,four fan-coil loops were formed, serving building areas with similar thermal behavior and operation profile.These loops were connected respectively to four water-to-water heat pump systems and they are capable of totally independent operation,meaning that,depending on the requirements of the zones they serve,some of them may provide heating while the others may provide cooling.Three Central Air Handling Units(AHUs)with water coils provide make up air to the building.The water coil of each AHU is connected to a group of heat pumps.The water coils of the AHUs and the fan-coils were selected for water inlet temperatures of40and98C,heating and cooling,respectively.A total of seven heat pump groups were installed,four serving the fan-coils and three the AHUs.The cooling capacity of each heat pump group is20–60kW,depending on the group. Each group consists of one to two in parallel-connected heat pumps,operating under common control.Twenty-one vertical boreholes(3Â7on a4.5Â4.5grid)up to a depth of80m consist the ground heat exchanger.Each borehole features a4in.diameter,with a single U-shape PE-HD tube—o.d.40mm.The primary circuitfluid is de-ionized water without any anti-freezing agent.In order to promote the thermal conductivity between the U-tubes and the surrounding soil,but also for their protection,a1:19betonite/cement mixture was used.As a backup of the ground heat exchanger,a120kW oil-fired conventional boiler and a cooling tower were installed.An overview of the system is shown in Fig.1.A central BMS is also foreseen,to fully control the operation of all the devices and networks of the system and also to provide system monitoring.This BMS has not yet been installed; presently control being provided either locally,with small autonomous units,or manually.An external data logging system is also installed,simply for monitoring the behavior of the whole installation.3.The data logging systemAim of the system is to provide an external overview of the operation of the installation,therefore only a limited number of data are recorded,as it follows:Ground heat exchanger inlet and outlet temperatures,using film-type4wire Pt-100temperature sensors.Ambient air temperature,using a3-wire Pt-100temperature sensor,located outside,at the NW side of the building, relatively protected from direct sunshine.Campbell Scientific,type CR-10data logger.One set of data,consisting of the three temperatures and the date and time of the day,is stored every10min.The central pump delivery is not recorded since,at least for the time being,its operation is of the on–off type,and repeated measurements in different days and hours(using the ultrasonic Panametrics PT878flow meter)revealed that it remains constant at48m3/h.Fig.2shows a typical winter day(heating period)recording. During the night the heat pump system is out of operation,and the water temperatures recorded correspond to the room temperature where the sensors are located.The system is turned-on at07:00and the water of the primary circuit starts to circulate.Temperatures gradually decrease to the operation level imposed by the ground heat exchanger,but the temperature gain can be clearly seen.Due to the increasing ambient temperature and solar gains,the thermal load of the building,is reduced at around noon,and,as result,water temperatures gradually increase.The heat pumps stop at14:30 and thefluid temperatures start rising,until,after about4h, they reach the equilibrium point(room temperature).Fig.3shows a typical recording of a summer day(cooling period).The inlet and outlet temperatures have mutually changed relative positions,meaning that the water is now cooled in the heat exchanger,and their level is significantly higher than that during heating.The start and end point of heat pump operation are again clearly visible(07:00and13:00, respectively).It can be also seen that the central circulation pump is always on.4.Operation resultsThirty-six months of operation monitoring have already been accumulated(January2003–December2005)and someA.Michopoulos et al./Energy and Buildings39(2007)328–334329 Table1Basic climate parameters of building’s areaLatitude/longitude408360/228590Heating period November–MarchHeating design conditions(99.6%)À58CMean daily temperature in January 6.18CHeating degree days(base188C)1800KdaysCooling period Mid of May–SeptemberCooling design conditions(0.4%DB/MCWB)34.0DB/21.0WBMean daily temperature in July268CUndisturbed ground temperature188C330A.Michopoulos et al./Energy and Buildings39(2007)328–334Fig.1.System overview.Fig.2.Typical recording of the ground heat exchanger operation for heating(28-02-2003).significant conclusions regarding the operation and economy of the system can be drawn.The energy exchanged between water and soil in the 10min interval between two successive entries of the data logging system can be calculated as Q ¼˙mc ð#out À#in Þ1060½kWh (1)where ˙m is the main pump water delivery [kg/s];c the specific heat capacity of water [kJ/(kg K)];#out the water temperature atthe ground heat exchanger outlet [8C];#in is the water tem-perature at the ground heat exchanger inlet [8C].The ‘‘instantaneous’’(10min interval)heat supplied to the building and the electricity consumption of the heat pump system can be calculated from Eq.(1),using the COP value given by the device manufacturer for the average between inlet and outlet water temperature.Based on Eq.(1),the heat exchanged between water and soil as well as the heat supplied to the building will be positive or negative.Conventionally,the heat supplied to the building (heating period)is taken positive.A.Michopoulos et al./Energy and Buildings 39(2007)328–334331Fig.4.Monthly distribution of heat exchange in the ground heat exchanger and operating hours for the period 01-2003to12-2005.Fig.3.Typical recording of the ground heat exchanger operation for cooling (16-07-2003).Obviously,the electricity consumption of the heat pump system is always positive,regardless of the operation mode.Fig.4shows the monthly values of the heat exchange between water and soil over the period monitored.It is observed that during the first year (January–December 2003)the system was in operation 24h/day,for heating or cooling.During the remaining period (January 2004–December 2005)the system was shut down during the intermediate seasons (April,May and October),since the ambient temperature during these months was in the range 15–188C,around the change over temperatures of the buildings zones,therefore there was no need for either heating or cooling.Fig.4shows also that the hours of operation per month for some months during the first year were up to 70%higher of the respective months of the next year,the respective loads being increased by as much as 97.5%.This can be attributed to the more extreme ambient conditions of 2003,as it is verified in Fig.5,where the average month temperature is plotted.Additionally,it has to be attributed also to the manual operation of the system and the lack of experience of the operator.This is verified by the monthly loads of the building shown in paring for example the data for Feb 2003and 2004,it is clear that despite the fact that the average ambient temperature is roughly the same,around 5.28C,the heating load in 2003A.Michopoulos et al./Energy and Buildings 39(2007)328–334332Fig.5.Monthly thermal load of the building and monthly average ambient temperature for the period 01-2003to12-2005.Fig.6.Seasonal COP of water-to-water heat pumps.was17.37MWh,while in2004only9.53MWh,meaning that in2003the rooms were heated far beyond the required temperature.Another important conclusion regarding the system operation is revealed in Fig.6.As it can be seen,there is an increasing trend of the seasonal COP for heating,from4.4to5.2and a much less enhanced decreasing trend of the seasonal COP for cooling,from 4.5to4.4.This is due to the cyclic(heating–cooling)operation of the system over the year,which imposes higher ground temperature at the beginning of the respective period.This ground temperature increase has a stronger influence on the heating mode rather than on the cooling one,because of the average temperature level.It is expected that the system will reach an equilibrium condition after a limited number of periods, with the corresponding seasonal COP stabilized.In order to form an energy comparison basis of the system, the electricity required around the year for heating and cooling the building with a more conventional air-to-water(AW)heat pump system was calculated,using the COP corresponding to the ambient air temperature of each10min interval.The heat pump of the system is assumed to produce hot or chilled water, which is then delivered to the existing fan-coils.Additionally, the energy requirements of a completely conventional system were calculated.This system is assumed to consist of an oil boiler with an efficiency of88%for heating and air-to-air split air conditioners(AA)for cooling.For the comparisons,an overall efficiency of33%is assumed for electricity production from fossil fuels.Only the thermal and cooling loads were considered in this comparison,i.e.the energy requirements for (a)water circulators,(b)de-icing of the AW heat pumps,(c) fan-coil blowers were neglected.The results of this comparison per month are shown in Fig.7.The equivalent total thermal energy per operation period for each system is listed in Table2. It is clear that the most energy demanding system for heating is the conventional boiler,followed by the AW,requiring respectively up to120%and50%more thermal energy than the GSHP(see Fig.7)or97%and45%period average(see Table2).For cooling,the worst system is the AA,followed by the AW,requiring respectively up to90%and50%more energy (see Fig.7)or55%and28%period average(see Table2).5.ConclusionsThe ground source heat pump system of the New City Hall of Pylaia-Thessaloniki(total enclosed area of1350m2), consisted of7groups of water-to-water heat pump,21 boreholes with80m depth and fan-coil units has accumulated 3years of trouble free operation in heating and cooling mode.The basic operation characteristics are constantly monitored over this period and the results show that the ground heat exchangerfield approaches equilibrium in terms of start and end period temperatures,this also reflected on the seasonal COP.The primary energy required by the system for heating is estimated to be lower by45%and97%(period average)as compared to that of air-to-water heat pump based and conventional oil boiler respectively.In cooling mode the relevant differences are estimated at28%and55%for air-to-water and air-to-air heat pump based systems.Thesefigures prove that inA.Michopoulos et al./Energy and Buildings39(2007)328–334333Fig.7.Energy demand comparisons of alternative systems. Table2GSHP thermal energy demand and the equivalent for the alternative systems perperiod and mode of operationPeriod Heating[GWh th]Cooling[GWh th]GSHP AW Boiler GSHP AW AA1st21.525.835.680.6103.5125.42nd16.722.731.539.346.157.63rd17.525.434.431.937.446.5both modes,heating and cooling,the GSHP system is significantly less demanding in terms of primary energy. References[1]C.Popiel,J.Wojtkowiak,B.Biernacka,Measurements of temperaturedistribution in ground,Experimental Thermal and Fluid Science25(2001) 301–309.[2]H.J.L.Witte,A.J.van Gelder,M.Serrao,Comparison of design andoperation of a commercial UK Ground Source Heat Pump Project,in: Proceedings of First International Conference on Sustainable Energy Technologies,Porto,Portugal,2002.[3]G.Phetteplace,W.Sullivan,Performance of a hybrid ground-coupled heatpump system,ASHRAE Transactions104-1B(1998)763–770.[4]A.J.Shonder,D.Baxter Van,J.P.Hughes,W.J.Thornton,A comparison ofvertical ground heat exchanger design software for commercial applica-tions,ASHRAE Transactions106-1(2000)831–842.A.Michopoulos et al./Energy and Buildings39(2007)328–334 334。

合集下载

游戏公司创业计划书英语

游戏公司创业计划书英语

游戏公司创业计划书英语1. IntroductionThe gaming industry is a rapidly growing market that offers tremendous opportunities for innovation, creativity and profitability. With the increasing popularity of gaming across all platforms, there is a growing demand for high-quality, engaging and immersive gaming experiences. This business plan outlines the establishment of a game company, which aims to capitalize on this growing trend by creating and publishing innovative and interactive games across various platforms.2. Executive SummaryThe game company, [Company Name], will be a new player in the gaming industry, focusing on developing and publishing games for PC, console and mobile platforms. The company will be led by a team of experienced professionals with a proven track record in the gaming industry. The primary goal of [Company Name] is to create high-quality games that offer unique and immersive experiences to players, while also providing a sustainable and profitable business model.3. Company Description[Company Name] will be headquartered in [Location], with additional offices in key gaming hubs around the world. The company will initially focus on developing and publishing games for the PC and console market, with plans to expand into the mobile gaming space in the future. The company will operate with a lean and agile structure, to ensure flexibility in adapting to the constantly evolving gaming landscape.4. Market AnalysisThe gaming industry is a multi-billion dollar market that continues to grow year on year. The increasing popularity of gaming across all demographics, from casual players to hardcore enthusiasts, presents a huge opportunity for [Company Name] to carve out a niche in the market. The industry is also seeing the emergence of new technologies, such as virtual reality and augmented reality, which present exciting possibilities for creating immersive and interactive gaming experiences.5. Competitive AnalysisThe gaming industry is highly competitive, with established players dominating the market. However, the industry also offers opportunities for new entrants to differentiate themselves by focusing on innovation, creativity and quality. By leveraging the experience and expertise of its team, [Company Name] aims to create a competitive advantage by delivering high-quality games that stand out in the market.6. Marketing and Sales StrategyTo reach its target audience, [Company Name] will utilize a multi-faceted marketing and sales strategy that includes digital marketing, social media, influencer partnerships, and participation in gaming events and conventions. The company aims to build a strong brand presence and engage with its community of players to create a loyal and dedicated fan base.7. Product DevelopmentThe core focus of [Company Name] will be on creating high-quality, immersive and engaging games for the PC, console and mobile platforms. The company will invest in developing games that offer unique and innovative experiences to players, while also ensuring that they are well-optimized and visually stunning. The product development process will be driven by a combination of market research, player feedback, and creativity to ensure that the games resonate with the target audience.8. Financial ProjectionsThe financial projections for [Company Name] are based on a conservative estimate of market demand for its games, as well as the estimated costs of development, marketing, and sales. The company aims to achieve profitability within the first three years of operation, with a steady growth trajectory over the following years. The financial projections are based on the assumption that the company will successfully bring to market innovative and engaging games that resonate with the target audience.9. Management TeamThe management team at [Company Name] comprises of seasoned professionals with extensive experience in the gaming industry. The team brings together expertise in game design, development, marketing, and sales, with a proven track record of delivering successful and commercially viable games.10. ConclusionThe gaming industry presents a unique opportunity for [Company Name] to establish itself as a key player in the market. With a focus on innovation, creativity, and quality, the company aims to create high-quality and immersive games that resonate with players across all platforms. This business plan outlines the roadmap for [Company Name] to achieve its goals and become a significant player in the gaming industry.。

软件测试英文面试自我介绍

软件测试英文面试自我介绍

软件测试英文面试自我介绍软件测试英文面试自我介绍（通用8篇）软件测试英文面试自我介绍篇1I’m Cheers.Lee, I’m twenty-six year old, I majored in E-business and with a bachelor degree. I’m single. And I love software testing, as the software quality is vital to the company’s customer, it also could improve the company’s image, so quality is the best policy. We must devote all my energy to assure the software quality.The position which I’ve come to apply is senior software testing engineer. I have three years work experience, one year and a half of function testing experience and one year of performance and automation testing experience. I have been reading up on software testing, especially on performance testing and automation te sting. I’m quite familiar with performance testing tool LoadRunner, and familiar with automation testing tool QTP. I’m good at developing performance testing script base on C language in web system, and also have good skills in develop QTP script.As we all know that software performance has become more and more important, while thousands of the users log in the system or visit the website simultaneously, the problem may occurred, the system crash or the server deny to provide the service to the user, so the performance testing need to be done before the software delivered to our customers.We also benefit from the automation testing. There is always a lot of function testing or regression testing need us to finish in a short time. But we do not have enough time and sufficient human resource to complete it, how should we do? So theautomation testing is the best solution. It cut down the costs, improve the work efficiency, save our time and energy. Its advantage is not merely as so.软件测试英文面试自我介绍篇2Well,it’s my pleasure to introduce myself.I’m yangcheng from Hu Bei province and I graduated from Hu Bei University for nationalities last year,.majoring in Information and Computer Secience,As you know,I’ve been working as a software engineer in a small company unt il September this year,because there’s something important I have to deal with back home.As far as I’m concerned,before a project can be put into practice,there’s still much work we have to do,learning theories and methods of software test is a key point.Then,the Functional Requirement Specification must be analysed carefully and clearly so that we can design test plans and test cases fluently.Finally,we execute the cases and keep an eye on whether the related modules work well,meanwhile,we should find,track and fix bugs in order to make sure the whole quality of a software can meet customers’need.软件测试英文面试自我介绍篇3My name is . I'm years old. Please allow me to introduce myself:Learning, I think the students' main task is to learn professional knowledge, so I am learning sureness, diligent. Do not relax, but also participated in many entertainment programs. For our computer related professional software testing students, light to learn book knowledge is not enough. In my spare time often reading computer books, and participated in a number of computer level exam, and achieved good results. Spare time can also be home to exercise their own.I think learning is the students' occupation, the occupation also need wisdom, perseverance and perseverance. In today's rapid development of the information age, only when we constantly learn new knowledge, we will not be outdated. Learning is important, a person ability can not be ignored. Four years of university life has given me a lot of challenge the opportunity, cultural festival of the Arts Festival, the Olympic Games volunteer activities.In the process of participating in these activities, I made some good friends, learned to deal with people, to exercise their abilities. These experiences make me know something if you try, the chance of success is half, if you don't try, the probability of success can only chance is zero. When we should hold well the collective life makes me understand how to understand others and care for others, I also make become more strong and independent.I feel that I should be responsible for my own affairs. Others can only give you some advice at most. I should think calmly when I meet something, not irritable. I promise not to make an easy promise, but I will try to cash it软件测试英文面试自我介绍篇4Examiner, I am a computer professional interviewer , this position is the IT industry software engineers, this work not only with my professional counterparts, but also my strengths and interests. Now I will introduce myself from the following three aspects:1) learning ability: I have a strong scientific research ability, skilled in Windows20xx and LINUX operations, and can use VB, DELPHI and other language programming. Can use the web page three musketeers Photoshop software related work2) practical ability: my specialty is software development, I hope I can do the work experience in this field, and I have sent many systems, such as personnel file management system, payroll management system and so on3) communication skills: my calm personality, can sit still, for the IT industry, has a very good ability to adapt, and modest man, has the very strong organization and coordination ability, full of dedication and sense of responsibility that I can face any difficulties and challenges.From the above simple self introduction, I hope the company can give me a chance to demonstrate your ability, so that I can apply what they have learned, and I also enjoy the company culture and working environment of company. I would like to become a member of the enterprise, their contribution to a force for the development of enterprises. The amount of occupation career goal I is a know technology, talents and understand the business.软件测试英文面试自我介绍篇5My name is xxx, began studying at Beida Jade Bird in September 2014, the main .net engineer. Beida Jade Bird training after a year and a half, to fully grasp the basics of software development, now has completed an independent software development, software engineering can also project development team. I believe in the future of work and learning will be very competent. Beida Jade Bird as a very happy and proud.Usually interested in playing basketball, so I trained really confident, optimistic, positive personality. Because not very talkative, so a lot of time in bookstores and books with friends. But that does not mean I introverted. Because I love to read.Personally prefer the phrase: any wide sea diving, the days of the bird. Xxx company is proud to be able to come, please exhibitions, very happy together to create tomorrow's brilliant colleagues!软件测试英文面试自我介绍篇6Good morning,It is really my honor to have this opportunity for a interview,I hope I can make a good performance today.Now I will introduce myself briefly.I am xiaoming , 25 years old,born in zhejiang province,east-south of china.I am currently a graduate student at xxx University ,My major is signal and information processing.and I will get my master degree after my graduation in April, 20xx. I got my bachelor degree in at xxxx Major in Electrical Information engineering.I spent most of my time on study,I have passed CET6.and i have acquired basic knowledge of my major during my school time. Such as C, C++, data structures,some classic algorithms, Computer networks, and linux operation system.In addition to doing some related academic research, I have also done some project. Last year, I have finished the Intelligent multimedia learning system with my team, from which I have had a good knowledge of Software Development Process, including demand analysis,general design, software coding,performance test,and I have also found interest in software development. That is the reason why I come here to compete for this position.I think I'm a good team player and I'm a person of great honesty to others. Also I am able to work unde r great pressure.That’s all.Thank you for giving me the chance!软件测试英文面试自我介绍篇7My name is 20xx, I started studying at Beida Jade Bird in X, and I was the chief engineer After prize.the 1 and a half years of training, to fully grasp the basic knowledge of software development, can now complete the independent software development work, also can team of software project development. I believe in the future work and learning will be very good. As a member of the blue bird is very happy and proud.Likes playing basketball, so I developed a confident, optimistic, positive personality. Because don't speak too much, so a lot of time in the bookstore and book friends. But this does not mean I am introverted. Because I like reading.People love a word: the width of the sky. I feel honored to come to , please exhibitions, glad to colleagues together to create a brilliant tomorrow!软件测试英文面试自我介绍篇8Good morning,It is really my honor to have this opportunity for an interview. I hope I can make a good performance today.I'm confident that I can succeed. Now I will introduce myself briefly. I am 26 years old, born in Shandong province. I graduated from Qingdao University. My major is electronics. And I got my bachelor degree after my graduation in the year of 20xx.I spent most of my time on study, and I’ve passed CET-6 during my university. And I’ve acquired basic knowledge of my major. It is my long cherished dream to be an engineer and I am eager to get an opportunity to fully play my ability. In July 20xx, I began working for a small private company as a technical support engineer in Qingdao city.Because there was no more chance for me to give full play to my talent, so I decided to change my job. And in August 20xx, I left for Beijing and worked for a foreign enterprise as an automation software test engineer. Because I want to change myworking environment, I'd like to find a job which is more challenging. Moreover， Motorola is a global company, so I feel I can gain a lot from working in this kind of company. That is the reason why I come here to compete for this position.I think I'm a good team player and a person of great honesty to others. Also，I am able to work under great pressure. I am confident that I am qualified for the post of engineer in your company.That’s all.Thank you for giving me the chance.。

写一下初中三年的变化及感受英语作文

写一下初中三年的变化及感受英语作文

写一下初中三年的变化及感受英语作文全文共10篇示例，供读者参考篇1Title: My Experience of Three Years in Junior High SchoolHey guys, today I wanna share with you my three years of experience in junior high school. It has been quite a journey for me, full of ups and downs, challenges and achievements. Let me tell you all about it!When I first entered junior high school, I was super nervous. The school was so big, and there were so many new faces around me. I didn't know anyone in my class, and I was afraid of being alone. But soon enough, I made friends and got used to the new environment. I found my way around the school, and started to enjoy my classes.In the first year, I struggled a bit with the workload. The subjects were harder than in primary school, and I had to study more to get good grades. But with the help of my teachers and classmates, I managed to do well in most of my subjects. I also joined some extracurricular activities, like the school band and the basketball team.In the second year, I started to feel more confident in myself.I made even more friends, and I became more active in school events. I participated in debate competitions and science fairs, and I even won some prizes. I also started to think about my future and what I wanted to do after graduation. I talked to my teachers and counselors, and they helped me figure out my interests and strengths.And now, in my third year, I am ready to graduate and move on to high school. I have learned so much in junior high school, both academically and personally. I have grown as a person, and I am excited to see what the future holds for me. I am grateful for all the experiences I have had, and I know that they will help me succeed in the next chapter of my life.So, that's my story of three years in junior high school. It has been a challenging but rewarding experience, and I am grateful for all the memories I have made. I can't wait to see what the future holds for me in high school! Thank you for listening, and I hope you enjoyed my story.篇2Oh my god! I can't believe I'm finally in sixth grade! It feels like just yesterday I was in third grade, and now I'm starting middle school! Time sure flies by fast, doesn't it?In my first year of middle school, everything was so new and exciting. I had to switch classes for different subjects, and I even had different teachers for each class! It was a big adjustment, but I quickly got used to it. I also made a lot of new friends from different elementary schools, which was really cool. The workload was a bit harder than elementary school, but I managed to keep up with my classes.As I moved on to seventh grade, I started to feel more confident in myself. I joined the school soccer team and made even more friends. I also started to think about my future and what I wanted to be when I grew up. English class became more challenging, but I enjoyed learning new words and grammar rules. I even started to write short stories in English!By the time I reached eighth grade, I felt like a pro at this whole middle school thing. I was elected class president and got to give a speech in front of the whole school! I felt so proud of myself. My English skills had improved a lot, and I started to read more English books and watch English movies without subtitles.Looking back on my three years in middle school, I can't believe how much I've grown and changed. I've become more independent, confident, and determined. I've learned so much, not just academically, but also about myself and what I'm capable of. I'm excited to see what the future holds for me, and I know that I'll always cherish the memories of my middle school years.篇3I wanna tell you guys about my three years in junior high school. It was like a rollercoaster ride, full of ups and downs, but boy, did I learn a lot!First year of junior high was super exciting. I remember feeling so grown up and cool with my new uniform and big bag. The classes were harder than elementary school, but I was ready for the challenge. I made new friends, joined clubs, and even tried out for the school play. It was all so much fun!But then came second year, and things got a bit tougher. The teachers started piling on the homework, and I had to start thinking about my future. I had to choose my elective classes and start planning for high school. It was a little overwhelming, but I knew I had to buckle down and focus.And finally, third year rolled around. It was a whirlwind of emotions - excitement for high school, sadness to leave junior high behind, and nerves for exams. I had to study like crazy, but I also made sure to have fun with my friends and make the most of my last year.Looking back, I can't believe how much I've grown in these three years. I've learned to be more independent, to manage my time better, and to never give up when things get tough. Junior high was a wild ride, but I wouldn't change a thing. Bring on high school - I'm ready for whatever comes my way!篇4Wow, time flies! I can't believe it's been three years since I started middle school. So many things have changed and I've learned so much. Let me tell you all about it.In my first year of middle school, everything was new and exciting. I was nervous at first, but soon I made new friends and got used to the routine. We had more subjects to study, like science and history, and I found that I really enjoyed learning about different topics. I also joined some clubs and tried out for the school team, which helped me discover new interests and talents.In my second year, things got a bit tougher. The teachers started expecting more from us and the workload increased. I had to learn how to manage my time better and stay organized. But I also found that I was getting better at certain subjects, like math and English. I started to set goals for myself and work harder to achieve them.And now, in my third year of middle school, I can really see how much I've grown. I have more confidence in myself and my abilities. I know how to study effectively and ask for help when I need it. I've also learned how to handle setbacks and disappointments, and not to give up when things get tough.Overall, these three years of middle school have been a rollercoaster of ups and downs, but I wouldn't change a thing. I've made great friends, learned so much, and grown into a more mature and responsible person. I'm excited to see what the future holds, but I know that I'm ready to take on whatever challenges come my way.篇5Oh wow, let me tell you all about my three years in junior high school! It was like a rollercoaster ride with so many changes and feelings.In the first year, everything was so new and exciting. I remember feeling a bit nervous on the first day, but soon I made new friends and got used to my schedule. I had more subjects to study like science, history, and geography. It was a bit challenging at first, but I started to enjoy learning new things.As I moved on to the second year, I started to feel more confident. I joined some clubs and activities like the school choir and basketball team. I also started to think about my future and what I wanted to do after graduation. The workload was heavier, but I managed to balance my studies with my hobbies.And finally, in the third year, I was faced with the challenge of preparing for high school entrance exams. It was stressful and overwhelming at times, but I pushed myself to study hard and stay focused. I learned how to manage my time wisely and ask for help when I needed it.Looking back, I can see how much I have grown and changed over the past three years. I have become more independent, responsible, and determined. Junior high school has taught me so much, not just academically, but also socially and emotionally. I am grateful for all the experiences and memories I have made, and I am excited to see what the future holds for me in high school.篇6Oh my goodness! Can you believe how much I've changed in my three years of middle school? It's like I'm a totally different person now!In my first year of middle school, I was so nervous and scared.I didn't know anyone in my classes and I felt like a little fish in a big pond. But as the year went on, I started to make friends and feel more comfortable. My English class was a struggle at first, but with lots of practice and hard work, I started to improve.By the time I reached my second year of middle school, I was feeling much more confident. I was getting better grades in English and I even joined the school debate team. I started to really enjoy reading and writing in English, and I felt proud of my progress.And now, in my third year of middle school, I can't believe how far I've come! I'm one of the top students in my English class and I even won a writing competition. I feel so comfortable speaking and writing in English now, and I'm excited to see where my language skills will take me in the future.Looking back on my time in middle school, I am so grateful for the growth and opportunities that learning English has givenme. It's been a challenging journey, but I know it was worth it. I can't wait to see what the future holds for me and my English skills!篇7Wow, I can't believe how much I've changed over the past three years of middle school! It feels like just yesterday I was a little elementary school kid, and now I'm almost a high schooler. So many things have happened and I've learned a lot along the way.In my first year of middle school, I was so nervous and excited at the same time. Everything was new and different - new teachers, new classmates, new subjects. I remember feeling overwhelmed at first, but as the year went on, I started to get the hang of things. I made new friends, discovered my favorite subjects (hello, English!), and even joined a few clubs.By the time I reached my second year of middle school, I felt much more confident and comfortable. I knew my way around the school, I had a solid group of friends, and I was getting better grades. I started to take on more responsibilities and challenges, like joining the school basketball team and participating in the science fair. It was a lot of work, but I was having a blast.And now, in my third year of middle school, I feel like a completely different person. I've grown so much - not just physically, but emotionally and academically as well. I've learned to manage my time better, speak up for myself, and push myself to do my best. I've faced some tough moments along the way, like failing a test or losing a game, but I've always bounced back stronger.Looking back on the past three years, I can't help but feel proud of how far I've come. I've made mistakes, I've had successes, and I've learned so much about myself and the world around me. Middle school has been a rollercoaster ride, but I wouldn't trade it for anything. I'm excited to see what high school has in store for me, but I'll always cherish the memories and lessons from my middle school years. Bring it on, high school - I'm ready for you!篇8Oh my goodness, can you believe how much I've changed in three years of middle school? It's been a wild ride, let me tell you!First of all, I have to say that my English skills have improved so much since I started middle school. I used to struggle with grammar and vocabulary, but now I can write essays and speakconfidently in English. It's pretty amazing how much I've learned in just three years!Another big change is how much more independent I've become. In elementary school, my teachers used to give me a lot of guidance and support, but in middle school, I've had to learn to manage my time and responsibilities on my own. It was tough at first, but now I feel like I can handle anything that comes my way.I've also made a lot of new friends in middle school and my social skills have improved a lot. I used to be shy and nervous around people I didn't know, but now I'm confident and outgoing. I love hanging out with my friends and going to school events like dances and sports games.Overall, I feel like I've grown a lot in the past three years. I'm more confident, independent, and knowledgeable than I was in elementary school. I can't wait to see what the next three years of high school will bring!篇9Oh my goodness, let me tell you about the changes and feelings I had during my three years in junior high school! It waslike a roller coaster ride, with ups and downs and twists and turns everywhere.When I first started junior high, I was so nervous and excited at the same time. Everything was new and different, from the teachers to the classmates to the subjects we were studying. I remember feeling overwhelmed by all the homework and tests we had to do, but also feeling proud of myself for being able to handle it all.As the years went by, I started to feel more confident and comfortable in school. I made new friends, discovered new interests, and even found my passion for certain subjects like English and science. I joined clubs and extracurricular activities, and I even participated in some competitions and events.But there were also challenges along the way. I struggled with some subjects and had to work extra hard to improve my grades. There were times when I felt stressed and worried about not doing well, but I never gave up. I asked for help from teachers and classmates, and I studied harder to overcome my weaknesses.And now, as I look back on my three years in junior high, I can't believe how much I've grown and changed. I've become more independent, more responsible, and more confident inmyself. I've learned so much, not just academically but also personally. I've made memories that will stay with me forever, and I've met people who have influenced me in so many ways.Overall, my journey through junior high school was challenging, rewarding, and unforgettable. I'm excited to see what the future holds for me in high school and beyond. Bring it on!篇10When I first entered junior high school, I was really nervous and excited at the same time. I remember feeling overwhelmed by the size of the campus and the amount of homework we were given. But as the years went by, I started to settle in and began to notice some big changes in myself.In my first year of junior high, I was still a bit shy and unsure of myself. I struggled to make new friends and found it hard to speak up in class. But as time went on, I started to gain more confidence. I joined different clubs and activities, which helped me to meet new people and step out of my comfort zone. I also found that my English skills were improving, as I had more opportunities to practice speaking and writing in class.By the time I reached my final year of junior high, I felt like a completely different person. I had become more outgoing and sociable, and had a close group of friends that I could rely on. My English had also improved dramatically, and I was able to have conversations with my teachers and classmates without feeling nervous. I was even chosen to represent my class in an English speech competition, which was a huge achievement for me.Looking back on my three years of junior high, I can see how much I have grown and changed. I am grateful for the opportunities I had to learn and improve, and for the support of my teachers and friends along the way. I am excited to see what the future holds for me in high school, and I know that I am now better prepared to face any challenges that come my way.。

美国移民签证类型（ImmigrationvisatypesintheUnitedStates）

美国移民签证类型（ImmigrationvisatypesintheUnitedStates）

美国移民签证类型（Immigration visa types in the United States）Two, the United States immigration visa typeThe type of visa for the immigrant beneficiary depends on the type of immigration that the US applicant applies to the US citizenship and immigration office. In most cases, the visa category is determined by the relationship between the American applicant and the beneficiary. According to the immigration law, some visa applications can be started immediately, while other visa categories are limited in number and have to wait until a certain period of time before they are eligible to start. That is, a limited number of visa applications can be processed only after the departure date of the visa. The immediate family of an American citizen is eligible to attend a visa interview after the citizenship and immigration service has approved his immigration application and transferred the file to the immigration and Visa Department of the United States Consulate General in Guangzhou. The term "immediate family" refers to the parents, spouses or minor children of an American citizen (unmarried and under 21 years of age). Every immediate family must have an independent immigration application file.Visa application category for US citizens and overseas family membersVisa category not subject to visa quota restrictionsIR/CR1: spouse class visaIR/CR2: Children's visaIR3/IR4: adoption visaIR5: parent class visaK1: fiance (wife) class visaK3: spouse class non immigrant visaVisa category restricted by quota of visaF1: US citizens' unmarried children visaF3: US citizens, married children, visasF4: US citizens, brothers and sisters visasVisa categories for overseas passport holders of us green card holders subject to visa quota restrictionsF2A: US green card holder, spouse and / or child class visaF2B: US green card holder, unmarried children's class visaLabour immigration visa categoryE1: first class firstE2: second categories firstE3: third categories firstE4: fourth categories firstE5: fifth categories firstOther visa categoriesSB1: visa back to the United StatesDV: draw visaThen go to the United States class visaIf you have a legitimate long-term Jumei identity, you hold the visa allows you to bring them into the United States, you can go to the U.S. citizenship and immigration services for your spouse and under 21 years of age and unmarried children then apply for visa. Applications should be made available to the U. S. citizenship and immigration office to prove that your relationship with your family was established before you changed your identity. Please note that the consulate no longer accepts direct applications for immigration to the United states. All such applications must be made through the corresponding US citizenship and immigration office in the United states.Occupational immigrant visa classificationAccording to the current immigration law, the number of people who immigrate to the United States by occupation is 140 thousand quotas annually. They are divided into five priority categories according to the conditions of different occupations andindividuals.E1 first priority: preferred labour (category three)1.. Outstanding in science, art, education, business, sport, foreign countries or countries.2. three years of teaching or research experience in a special academic field, and internationally recognized as an outstanding professor or researcher.3. senior managers of international trading companies require more than one year of working experience in the company during the first three years of the application, and the United States will continue to work in the same company or its business.E2 second is preferred; professionals with special skills with advanced degrees (category two)1. have a higher degree (Master's or master's degree) or equivalent (at least five years of experience in the field of expertise).2. having a special ability in science, art, and commerce, and having real use in the economy, culture, education, or welfare of the United states.E3 third priority: technical labour, professional and other labour (category three)1. refers to a bachelor's degree and has engaged in aprofessional (such as accountants, architects and engineers, etc.).2. technical worker, who has more than two years of vocational training or experience.3. other labour, including unskilled labour.E4 fourth priority: special immigrants (category nine)1. expected to regain American citizenship.2. religious workers.3. outside the United States for more than ten years to work for the U.S. government.4. employees working under the Treaty of the Panama Canal.5. graduates of certain foreign medical schools.6. some people who regularly travel to and from the United States border.7. certain retired officials of international organizations, their spouses and children.8. some who wish to regain permanent residency.9. some children have been declared non living capacity by the juvenile court.E5 fifth priority; investment immigrationAfter the new immigration law came into effect, it invested $five hundred thousand in the suburbs or in highly unemployed areas, or invested $one million in other areas of the country.Investment immigration is the fifth priority immigration in the new immigration law.In 1990 the new immigration law and investment in the United States expect foreigners to obtain permanent residency for the creation of the new immigrant species, in order to apply for such immigration, foreign investors must invest at least $one million (in the suburbs or high unemployment areas for $five hundred thousand) in a new American enterprise, and provide at least ten new jobs this investment, immigration visa from October 1, 1991 come into effect.Investment refers to the provision of capital, including cash, equipment, inventory, or other real assets, time deposits, government bonds and other readily convertible securities, and the payment of money, can be regarded as property.The applicant must create a commercial enterprise, pure real estate investment, buy land or housing, wait for appreciation, do not meet the requirements. The enterprise must be new, the purchase of a previously existing enterprises, but also does not meet the requirements, but there are workarounds.The new commercial enterprises include the following threekinds:1, the creation of a new business; 2, buy troubled enterprises, to rectify or reorganization, and retain the original staff. 3, the sale of existing business, and to expand.The new immigration laws restrict investment immigration by two years. That is, investors, immigrants and spouses and children can obtain conditional residence status. Two years later, if the immigration office finds that the investor does comply with the relevant provisions, investors and spouses and children can become permanent residents of the United states. Investors can hire 10 people on the last day of the limited investment within two years. After the investor and his family have obtained a green card, they can no longer employ employees if the work is not needed.The investor must maintain the operation and employment conditions of the new enterprise within two years, and maintain the survival of the enterprise in order to ensure the performance of the investment immigration obligations after 2 years, otherwise, it will not be able to permanently reside in the United states.。