**5. Research design and target population**

The research methodology adopted in this study was a descriptive survey type since this research method accurately describes the relation between variables, increase fairness, and maximize the reliability of the data. The method provides straightforward summaries about the sample and the observations that have been made. This ensured that appropriate answers are obtained for the research questions.

The data collecting techniques employed in this work is: subject matter literature surveys using: journal articles, books, related thesis papers; survey questionnaires; unstructured interview questions; visit and assessment of secondary sources such as factory maintenance log book, annual finance reports, published documents, and work order sheets.

The data used in this study have been collected from primary and secondary sources. Primary sources focused on information that helps to have entire understanding of the study through different techniques such as interviews, questionnaires, observations, and discussions, whereas secondary sources of information related to the study have detail understanding with the supportive documents and reports. Both quantitative and qualitative data were collected.

Non-random sampling which is purposive technique was selected in this study because this type of sampling is extremely functional to construct reality, describe a phenomenon or build up an impressive about a universe using specific knowledge. This sampling strategy is feasible to quantitative researches.

The sample for this study is taken from the target population of maintenance department, production department, and management parts of AWF at the two sites (Lideta and Mekanisa)

Population variability, availability of participants, and the suitability to the required information are factors considered when the sample size is determined.

Eqs. (4) and (5) are used to determine the sample size since the population is finite.

$$\mathbf{N} = Z^2 P (\mathbf{1} - \mathbf{P}) / \mathbf{C}^2 \tag{4}$$

$$\text{Ns} = \frac{N}{1 + \frac{N-1}{\text{No}}} \tag{5}$$

where N = sample unit (initial sample size)

Z = value of level of confidence (consider 90% confidence level, Z is 1.645) P = percentage picking a choice expressed as decimal 0.5 used for sample size needed

C = confidence initial expressed as decimal 0.08 = +/� 8%

Ns = size of targeted sample

No = size of the population (214 in this study)

Applying Eqs. (3.1) and (3.2), the target sample size is determined as: N = 105 and Ns = 70

#### **6. Summary**

The first part of the questionnaires presented on the six parameters was discussed in primary data analysis, and the result is summarized as follows:

#### *Implementation of Computerized Maintenance and Management System in Wine Factory… DOI: http://dx.doi.org/10.5772/intechopen.93007*

Regarding the worth given to maintenance, most of the respondents agreed that the attention given to maintenance department is less and it is not considered as a business center rather as a cost center. The budget for maintenance is negligible when compared with other departments. The maintenance management system is outdated, and the scheduling operation plan of maintenance department is poor. The common maintenance action takes place in the company is breakdown based which contributes much for breakdown time increment.

Concerning the intense of the company toward preventive maintenance, the respondents assure that there is a fixed time based preventive maintenance that takes place once in a year regardless of the condition of machines/equipment. However, priority is for reactive maintenance than preventive. While coming to maintenance planning and scheduling, most of the respondents disagreed on the presence of planned and scheduled maintenance. The back log control system, recording and documentation system of the company is said to be meager. The maintenance work is not prioritized technically. The maintenance work recording and documentation system is loyal to mistake and not used as a source for next work. The repair work analysis habit is so poor and needs to be changed. The company puts much effort toward training, and the communication system in the company is committed. The inventory management mechanism is so poor that is why much cost is elapsed when compared with the other maintenance expenses in the company.

The second part of the questioner shows that the frequently failed and bottleneck machine in the company is washer machine with the production rate of 64.17%. The main causes of the losses in production are stated as mechanical failure in washing section which covers the largest portion (35%), maintenance strategy followed by the plant (27%), maintenance management program (25%), and high cost of maintenance inventory control, and other (13%).

The company has got problems of highest machine breakdown time resulted in a loss of 1,188,950; 1,126,600; 1,174,975 bottles of wine in 2018, 2017, 2016 production year, respectively. In production year 2018, the total product is given by (2336– 116.5) hour 4300 bo/hour = 9,543,850 bottles. The loss in production in this year is (116.5 + 160) hour 4300bot/hour = 1,188,950 bottles which is 12.46% of the total product. In addition to production loss, high amount of money is elapsed in maintenance in the stated production years due to the lack of proper maintenance strategy and management system.
