Please use this identifier to cite or link to this item: http://hdl.handle.net/11527/16973
Title: İnşaat Firmalarında Satın Alma Yönetim Sistemi
Other Titles: The Purchasing Management System In The Construction Companies
Authors: Sey, Yıldız
Güler, Rahime
55564
Mimarlık
Architecture
Keywords: Satınalma
İnşaat işletmeleri
Purchasing
Construction enterprises
Issue Date: 1996
Publisher: Fen Bilimleri Enstitüsü
Institute of Science and Technology
Abstract: Günümüzde inşaat sektöründe giderek daha kompleks ve büyük boyutlu projeler gündeme gelmekte ve süre, maliyet, kalite açısından belirlenen hedeflere ulaşmak giderek daha da güçleşmektedir. Bu durum firmaların bu piyasada rekabet edebilmeleri için tüm yapım sürecini girişim aşamasından gerçekleştirme aşamasının sonuna kadar tümüyle etkin bir şekilde kontrol edebilmelerini zorunlu hale getirmektedir. Firmaların bu amaç doğrultusunda teknolojik gelişmeleri yakından izlemelerinin yanısıra üretim sürecini kontrol ederken çağdaş yönetim tekniklerini etkili bir şekilde kullanmaları kaçınılmaz bir zorunluluk haline gelmiştir. Teknoloji kendi yapısına uygun yönetimsel araçlarla desteklenmediği sürece amaçlara ulaşmada tek başına yeterli olmamaktadır. Tüm bu gelişmelerle büyük bir ivme kazanan yapı üretim sürecinin, bu üretim hızına cevap verebilmesi için, enformasyonun depolanması ve işlenmesini hedefleyen bir yönetim enformasyon sisteminin geliştirilmesi, önemli bir zorunluluk olarak karşımıza çıkmaktadır. Bu anlamda bir yönetim enformasyon sistemi oldukça kapsamlı olduğundan, kompüter destekli olarak tasarlanması ve geliştirilmesi yerinde olacaktır. Çağdaş yönetim tekniklerinin temel amacı doğru kararların doğru zamanlama ile alınmasını ve üretimin zamanında gerçekleştirilmesini sağlamaktır. Günümüzde bu amaca ulaşmak için gerekli olan koşullardan biri de etkili bir yönetim enformasyon sisteminin geliştirilmesi olarak karşımıza çıkmaktadır. Bugün inşaat firmalarımızın en büyük sorunlarından biri firmaların şantiyede gerçek leştirdikleri üretimin her yönüyle planlanması, denetimi ve değerlendirilebilmesine olanak sağlayacak enformasyonun, sistematik bir biçimde kaydedilmesine, olanak sağlayan bir yönetim enformasyon sisteminin eksikliğidir Bu tezin amacı, günümüzde üretim sürecinin yönetiminde kullanılması kaçınılmaz bir zorunluluk haline gelen çağdaş yönetim tekniklerinin kullanımına olanak sağlayacak bir yönetim enformasyon sisteminin oluşturulması çalışmaları kapsamında satın alma yönetim enformasyon sisteminin tasarlanması şeklinde açıklanabilir. Bu amaçla tez kapsamında ele alman uygulama çalışması, bir inşaat firmasının şantiye organizasyondaki satın alma faaliyetleri ve bu organizasyon ile projedeki diğer birimler arasındaki enformasyon akışı gözönüne alınarak, proje düzeyinde bir satın alma yönetim enformasyon sisteminin tasarlanması ve geliştirilmesine yönelik bir çalışmadır. Bu amaçla, ülkemizdeki bir inşaat firmasının yapımını üstlendiği ve maliyet+kar sözleşme usulü ile gerçekleştirilen bir projedeki satın alma faaliyetleri ve projedeki diğer birimler arasındaki enformasyon akışı incelenerek, proje düzeyinde bir satın alma yönetim enformasyon sisteminin tasarlanması ve geliştirilmesine yönelik bir uygulama çalışması yapılmıştır.
It has turned out to be an inevitable necessity for the construction firms to control the construction period starting with the undertaking period till the end of the accomplishment effectively in order to compete in the construction sector and succeed in their planned aims in the frame of cost - time - quality. As more wide and complex projects are now on the agenda in the construction sector, the control of the construction period is needed. It is not enough for a successful company management only to follow the technological developments in order to succeed, however, the control of the building period with the modern management methods plays a role in the company success as much as the technology. Within the improvements in the industry reform, the mechanization of the production sectors has been faster and so the productiveness has increased seriously. As the productivity has grown up, more production with the same time and same amount of workers and a great amount of material usage have been faced. All these developments have brought out the consideration of various factors in the field of production and with the necessity of the rational employing of the resources, the applying of innovative technological management methods. For the construction productivity period to meet the rapidity of this production, we face the important necessity of the improvement of a management information system aiming the deputing and processing of a vast capacity of information intended at different purposes in the various periods. Since the content of this management information system is extremely wide, it would be a true intention to plan and develop with the computer support. Nowadays, in many of our construction companies, because of not having a systematical data base, this system cannot provide the expected output. The main purpose of the modern management methods is the correct timing and the correct decisions and the production on time. In order to reach this purpose, the depoting and using of information systematically are among the main terms. Today, one of the important problems of the construction companies is the lack of an administrative information system in this sense. As the production capacity has increased and new technologies used due to automation,the new and complex materials starting to be used in the Construction production on top of the need for many and fastly constructed buildings after 2. WW; the construction sector has gone into a new era of structural changes. Since the need for many and fastly constructed buildings brings the necessity of large quantities of material being acquired in a short period of time, the rendering secure of material has an increasing importance. Parallel to these developments, the need in the developing prefabrication sector for the speedy and nonstop delivery of materials and components too has brought about the clear reality of the need for an affective Purchasing Management system. IX As explained above, supposing that generally the highest cost entry is the material and that it is possible to control the material costs with an effective Purchasing Management system; The importance in the sector preventing the other materials becoming of the Purchasing management system used for project materials management, can be seen clearly. The Purchasing management system,apart from providing the materials to reach the site on time and therefore minimizing the financial and storage expenses as well as preventing the other sources becoming idle and creating additional expenses, it creates an opportunity by connecting each purchasing step to the next,to minimize the personnel mistakes generated by the purchasing staff. The Purchasing Management System which aims at managing the purchasing process effectively, contains a sequence of activity. These activities has to be followed one by one yet connecting each to the other. Each of these activities contains such a broad area that could be classified as the sub systems of Purchasing Management system. The main sub systems contained in the Purchasing Management system can be summarized as Material need planning system, purchasing system, seller information and price following system, Material dispatch system. The starting date of the purchasing process is determined by establishing the dates and amounts relating to needs for the materials and the period from the date of the need to the ordering date of each material is calculated.The purchasing sub system receives the purchasing request and provides that the order is done and the purchasing steps are taken in a systematic way. The seller information and the price following sub system includes the market analyses, the collecting of sellers and price information as well as the validations as to the agree ability to the contract of the works done. The materials flow following sub systems includes the giving of orders, the following of materials dispatch and by studying the affects of delays to the work program, it searches for the ways of preventing the delay. The organizational forms of the Purchasing Management systems within the Construction companies, shows variations depending on the activity are of the companies. The purchasing organizations in the companies which are generally giving importance to the work in foreign countries, are units operating under the names of Logistics, supply, or purchasing and the coordination between the construction sites and the headquarters are done through the regional Purchasing office. These functions are usually performed through the purchasing unit in the construction site in the case of the companies doing domestic work. Only the materials apart from sand, gravel and cement,that are not directly related to the project are purchased by the purchasing unit in the head office. The central purchasing unit here mostly is a support unit and the purchasing processes are performed by the purchasing unit in the construction site. It has become necessary that they form, in another word, for the companies who are mainly working on projects in foreign countries to compete within the international market in the area of purchasing systems, the purchasing organizations in accordance with their individual needs. * Despite having mentioned the specific organizational variations between the domestically inclined and foreign country inclined construction companies, it should also be mentioned that there are differences among the companies who are working in foreign countries and domestically. For example, one of the companies who has currently moved most of its operations to the foreign countries has also taken the responsibility of large constructions domestically as well. It has been observed that the purchases relating to these projects are usually tried to be done on each project base and the head office is not consulted for all the purchases. On the other hand,the purchases relating to the works in the foreign countries are done through the purchasing unit at the head office. But the person or the unit who performs these purchasing tasks from the head office are different in each company. * The problems faced by the companies who work in the foreign countries and domestically, usually start with lack of standards and some systems which are used generally for all the sector and especially the development of competing opportunities for the companies working in foreign countries. The formation of these standards will bring means to ease the revising of the organizational forms and development. In addition, when the organizational forms of the companies are examined, it is understood by looking at the international construction companies that, they are more systematic and that this system did not just happen by itself but is the result of a conscious effort. Since it is difficult for the companies who are not organized as such, it is necessary that the companies wishing to work in foreign countries do enter into this renewal process. This kind of a renewal process is yet to be observed in the large construction companies who are working domestically. This than, shows that in our country, there is not much work done within the construction sector relating to the process and the quality of the output product and that the companies do not see themselves obliged to make the changes. As the amount of the companies who has been working in the foreign countries and therefore developing themselves compared to the others increase, the companies which are not wanting to fall behind in this renewal and development process, will have to keep in step. Otherwise, it won't be possible for them to continue operating. Apart from performing the purchasing functions, the Purchasing Management System, by causing the overseeing of Purchasing process system in order to systematically control the later purchasing jobs, should be integrated with the other systems in the company. The comparison should be done by checking the purchases performed for the different projects, and if there are any increases observed in the materials costs in the various stages of the project cost control, the factors effecting these increases should be studied. It is very difficult to do these studies, especially in the large projects, without a computerized system. Likewise, it is very important,in order the process to be carried out easily, to establish a computerized program for the control of the relations between the work program and materials obtaining program. Yet, it is not very easy to perform such overseeing in the construction companies and there is not a permanent supervising and reporting system in majority of the construction companies. The formation of an effective purchasing management system requires that an information system relating to this matter exist. The related studies have just started to take place in some of the foremost companies in our country. It is realized that the purchasing management system be given importance in the cost control and XI information systems because of its importance in inter-company organizations as well as the share of materials in the overall costs and the efforts towards this has been increased. In order for this kind of a system to be set up,it is inescapable that the Purchasing Management information system be developed. There has been a study performed on the purchasing management systems in one of the leading companies of Turkey. The aim of the thesis is the planning, organizing, execution and supervising of these functions relating to the Purchasing management. The most important problem when developing such a Purchasing Management Information system is the non -existence of a data bank about the sellers and producers and the difficulty in producing documents relating to the purchases done previously. The traditional performing of these purchasing functions and non- application of new information and modern management systems in these companies brings these results with it. As a result of all these reasons, the formation of such a Purchasing management information systems,to which all the project executors and purchasing authorities will have access to in order to obtain information from a computerized system whenever wanted.necessitates more efforts and time. There are some researches carried out on the possibilities of different assurances in different parts of the world, especially by the companies who are opening to the world outside. It is observed that these companies who are already performing tasks in foreign countries have started to transfer into a computerized system relating to the storage of information about construction materials producers and sellers. But these works are only limited to the areas in which the said companies work. Keeping in mind that one of the stages that the construction companies feel the need to an information system is the planning of project period, cost and resources ;and keeping also in mind that the most important source relating to the production is the materials; the importance of the formation of a purchasing management system in a information system about the materials purchasing is clearly seen. It is possible to make a proper planning by starting from the analyses and performance values already done about this subject. After the conclusion of each project, the records of this project create a data base for doing analyses aimed at establishing various reasons. As explained above ;the existing structure which doesn't show a systematic formation, in other words, not showing a behavioral system, comes out as an insufficient natural result in order to keep the system alive. The purpose of this thesis is; to put a share into the efforts of forming a management information systems which will provide the opportunity for the use of contemporary management techniques, which have become necessary in the management of production process; by preparing a Purchasing management information system. This study, which has been taken on project basis, is a work towards the planning and development of a purchasing management information system on project basis, keeping in mind the typical purchasing operations in the company's construction site organization and the information flow between this organization and the other units within the construction site. The purpose of the practicing study in the content of thesis can be explained as for a wide range project undertaken by a domestic construction company, pointing out the type of the purchasing administrative information system supported by a computer Xll that will be useful in planning the time - cost and resources; in other words, after being planned in the conception level, the concreteness in the objectivity The applied study,of which the targets are described above, has two paces; 1. The analyses of the existing system 2. The development of new suggestion relating to the existing system The first step of the study being the determination of the companies needs, the first thing to be done towards this is to establish the existing situation with all of its details. At this stage, the typical purchasing organization of the company, the responsible staff and their responsibilities in this organization, the reports they need to present(outputs),the data (input)they need to produce these outputs and the processes (time period) needed for these data to be turned into reports, were tried to be determined. By determining from whom and which resources the responsible staff gets the information he needs in order to fulfill his functions, the quality of the information flow between the duty posts within the organization will be established. Throughout this study, the systematic structures used and the quality of the data base, the system of filing, the type and format of the reports will be determined in order to store the information. In order for the Construction companies to complete the large technology based and complex jobs in a competitive market and specific time limits,in other words, to compete within the international construction arena ; modern project management techniques and systems has to be equal to that of the international standards; has been suggested and the systems to be used as a base in the processes within this arena was tried to be formed. It has been pointed out that ;As the production increases and more production is achieved in a shorter time period, the acquisition of materials in larger quantities in shorter time periods becomes more important and that since the production speed has increased, the pauses in the production because of the delayed materials generates great losses and that this could only be overcome by an effective purchasing management.
Description: Tez (Yüksek Lisans) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 1996
Thesis (M.Sc.) -- İstanbul Technical University, Institute of Science and Technology, 1996
URI: http://hdl.handle.net/11527/16973
Appears in Collections:Mimarlık Lisansüstü Programı - Yüksek Lisans

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