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**A Method of Evaluating the Presence of Fan-Blade-Rotation Induced Unsteadiness in Wind Tunnel Experiments**

Josué Njock Libii

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Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/54144


**3. Results**

#### *3.1. Students' Awareness of Recycling*

All the respondents informed that they had heard of recycling and their main information sources were textbooks, newspapers and teachers. Students' understanding of recycling was evaluated with a multiple-option question and almost all the students correctly selected the option that stated, "Recycling is a process of converting waste materials into reusable objects". The students were also asked to identify the recyclable materials from a list of items. About 75% of them selected paper, 47% selected biodegradable materials, 46% selected plastic and glass, 38% selected metal, 17% selected wood, 16% selected electronics, and 10% selected textile. In addition, the students were asked to identify the universal recycling symbol from a list of four images referring to the symbols of the United Nations, recycling, waste disposal, and compostable (Figure 1). It appeared that almost all the students were able to recognise the recycling symbol.

**Figure 1.** Symbols: (**a**) United Nations; (**b**) recycling; (**c**) waste disposal; and (**d**) compostable.

#### *3.2. Test of the TPB Constructs and Their Correlations*

One-Way ANOVA tests were conducted to determine whether the demographic variables had any significant effects on the TPB constructs (Table 4). It emerged that 'gender' had statistically significant effect on the students' recycling intentions. The male students appeared to be more positive than their female peers towards related to their recycling intentions although the effect size was small

(Cohen's d = 0.27). In terms of 'age', students in the age group of 13–14 years demonstrated greater positive intentions, stronger social pressure, and higher perceived control over behaviour concerning recycling than the students in the age group of 14–15 years. The effect size appeared to be small as Cohen's d values ranged between 0.33 and 0.46. A Pearson's correlation test was performed to explore the relationships among the TPB constructs and the results showed some statistically significant and positive correlations among all the constructs except between SN and Attitude though the strengths of such relationships were weak (Table 4).

#### *3.3. Structural Model of the Students' Intentions to Recycle and Hypothesis Testing*

The hypothesised TPB model was statistically significant (*p* < 0.001) and showed an acceptable fit to the data ( χ2 = 82.42, χ2/df = 2.75, GFI = 0.94, AGFI = 0.89, CFI = 0.90, TLI = 0.85, RMSEA = 0.08). It explained about 56% of the variance (R2 = 0.56) in the students' intentions to recycle (Figure 2). It appeared that the predictor SN had the strongest and statistically significant positive effect (β = 0.64, SE = 0.08, t = 5.49, *p* < 0.001) on the students' intentions of recycling. Attitude had the second highest effect on Intention (β = 0.21, SE = 0.11, t = 1.85, *p* > 0.05) followed by PBC (β = 0.17, SE = 0.11, t = 1.35, *p* > 0.05), although their effects were insignificant. All the factor loadings on the latent constructs were above 0.50. Among the three hypotheses, only H2 appeared to be acceptable as SN had a statistically significantly effect on Intention, whereas, the other two hypotheses (H1 and H3) were rejected due to their insignificant relationships with Intention.

**Figure 2.** Structural model of the students' intentions to recycling ( *N* = 272). The bold straight arrow from Subjective Norm to Intention shows statistically significant relationship.

#### *3.4. Learning Possibility about Recycling and Students' Feedback*

About 92% of the students informed that they could learn more about recycling from their school. When the students were asked about the ways they could learn more about recycling, nearly 75% of them selected 'visiting a recycling facility', 62% selected 'teachers', 41% selected 'self-studying' and 29% selected both 'watching videos' and 'participating in debates'. About 74% of the students provided their free comments related to recycling and the survey procedure. Their comments reflected that they were interested to know more about recycling, as they appeared to be aware of its importance. There were comments from the students such as: "Recycling will make our country clean from waste material; recycling will make the world cleaner and greener; there are not many recycling bins in our county and therefore, some strict action should be taken regarding recycling of waste materials; a little amount of knowledge about recycling is not sufficient and therefore, schools need to take their students to recycling facilities for better understanding of the subject; and I believe that our natural resources are depleting at a faster rate than thought before and thus we must recycle everything as much as possible."

In addition, the students showed positive attitudes towards the survey as they thought that such a survey would enhance their awareness of recycling. Their comments were as follows: "This survey is quite inspiring and would promote the practice of recycling among young people; through the survey I am able to express my views on recycling; it has helped all the students to raise their awareness of recycling; some information on recycling should be provided by each school so that students can learn about it; the survey informed us about recycling, which we did not know beforehand; the survey was very useful as from our school we do not get much encouragement towards engaging in recycling; I will learn more about recycling by visiting a recycling facility; and being a nature lover, such environment related surveys are always appreciated by me but recycling facilities are very uncommon in India, which is a matter of concern."

#### **4. Discussion and Conclusions**

#### *4.1. Synthesis of the Major Findings*

The study investigated the socio-psychological determinants of school students' recycling intentions in India by applying the standard TPB framework. It also explored students' awareness of recycling and brought to the fore the educational aspects related to this issue. The findings of this study can be regarded as first-hand information on young citizens' recycling intentions. Results showed that almost all the students were aware of the concept of recycling. However, many did not perceive that plastic, metal, glass, wood, electronics and textile materials could be recycled. It also appeared that almost half of the students assumed biodegradable materials as recyclables.

The TPB model was able to capture a substantial variance in the students' recycling intentions, and thus the predictive utility of the model corresponded to a few earlier studies on this topic [47,49,55]. The emergence of SN as the most significant predictor of the students' recycling intentions contradicted the findings of most of the earlier studies where SN appeared to be the weakest among the TPB predictors although Wan et al. [47,55] found that SN had a significant role in determining individuals' recycling intentions in Hong Kong. The positive effect of PBC on recycling intentions corresponded to the findings of some earlier studies [55–57]. The insignificant effect of Attitude on the students' intentions of recycling was exceptional considering many studies reported Attitude as the strongest predictor of individuals' recycling intentions. However, this exception perhaps appeared due to the formulation of some of the items under the construct Attitude, which was somewhat different from the definition of Attitude given by Azjen [44].

These findings indicated that the social pressure would be driving Indian students' recycling intentions followed by their attitudes to recycling and their perceived ease of carrying out recycling activities. Jain et al. [81] have reported that since a *collectivist culture* prevails in India, SN tends to have a greater impact on intention than Attitude, and this could hold true in this study. The study found that the demographic variables had statistically significant effects on some of the TPB constructs although such effects were weak. The study by Oztekin et al. [57] found a gender difference in the Turkish university students' attitudes to recycling where female students were more positive than their male peers. However, the present study found an opposite result among the school students' attitudes to recycling in India. Overall, the school students demonstrated positive intentions and attitudes towards recycling and they were confident about their ability to participate in recycling activities. To some extent, these results corresponded to the study by Lucy et al. [40].

#### *4.2. Implications and Recommendations*

The study revealed that the students had some ambiguities about the materials that are recyclables. Such a lack of conceptual clarity about recyclable materials among the students can affect urban waste management program and make it costly for the municipalities. There is a high probability that due to this lack of knowledge among the youth, the segregation of wastes at source will be carried out improperly by them that will ultimately affect government's efforts towards urban waste management. Therefore, there is a clear need of raising awareness of recycling and recyclable materials among the youth in India. Wan et al. [55] have suggested that public authorities should position "recycling as a social trend and promote it in the society through encouraging messages from the celebrity personalities and showing the percentage or frequency of the local population performing recycling". It can be a relevant approach in the context of recycling, as Abrahamese and Steg [82] perceived that "socially desirable behaviours could be achieved in issues related to resource conservation by means of social influences, learning and comparison". Wan et al. [55] have also suggested that promoting recycling behaviour as a socially desirable trend instead of highlighting its benefits could be an effective strategy. It is evident that without increasing the knowledge of the benefits of recycling and improving individuals' waste separation abilities, socially desirable behaviours will be difficult to achieve in the context of urban waste management in India. Moreover, when it comes to developing students' recycling behaviours, schools can play an important role. Schools can initiate various environmental activities in their local communities involving students and residents, as the respondents in this study also suggested, which can enhance their awareness of waste separation and motivate them to take required practical actions both at the household and community levels [54]. There are already a few policies and initiatives existing in India related to urban waste management and therefore, it is the responsibility of the citizens, both young and old, to come forward and help implementing those policies successfully throughout the country.

#### *4.3. Limitations and Future Research Needs*

There were some limitations in the study, which are required to be addressed in the future research. The researchers collected data from only one school in Delhi and therefore, the sample cannot be considered a truly representative sample. Future studies should recruit a large sample of students from various Indian cities to improve the representativeness of the study as well as the generalizability of its findings. Moreover, besides school students, university students should be included in the future studies, as this will provide a comprehensive picture of the socio-psychological factors determining Indian youth's recycling intentions. Future studies could also explore the socio-psychological factors that affect recycling intentions of both the youth and adults to understand their similarities and differences across the two age groups, which could be useful in building relevant hypotheses. Apart from recycling intentions, past recycling behaviours should also be studied to observe possible gaps between intentions and behaviours. A number of studies also added constructs such as 'personal norm', 'awareness of consequences', 'environmental knowledge', 'past behaviour', 'self-identity', and 'situation factors' to the extended TPB frameworks to explain individuals recycling intentions, which appeared to be relevant [54,55,57,83–85]. Therefore, future studies could use such extended TPB models to predict young citizens' recycling intentions and behaviours in India. Future studies could also investigate how economic rewards (i.e., payment for recyclables) could influence young generation's intentions towards recycling as the lack of financial incentives was identified in many of the previous studies as one of the factors that affected individuals' recycling intentions.