Abstract-The use of wireless sensor networks to protect sensitive facilities or international borders has attracted more and more attention. In contrast to previous studies in which the barrier coverage problem was solved under the assumption of an omni-directional sensing model, the current study presents a scheme for constructing k-barrier coverage using randomly deployed sensors with directional sensing model. The performance of the proposed scheme was evaluated using the ns-2 network simulator and compared with that of an omni-directional sensing scheme. Overall, the results show that for a given sensing range, the proposed directional sensing scheme achieved k-barrier coverage with a fewer number of active sensor nodes than the omni-directional sensing method. Moreover, the directional sensing scheme demonstrates a more robust ability than the omni-directional sensing method in constructing kbarrier coverage as the length of the belt increases or the node density within the sensing field decreases.

A product form design and evaluation model are proposed. In this method, the forms can be evaluated by three sub-evaluation models which can help designers to grasp consumers’ preferences. In the process, the overall shape is first disassembled into several shape elements, and a morphological chart is constructed. Then, the priority of shape elements is analyzed through the fuzzy analytical hierarchy process, and several required combinations are selected from a morphological chart. Moreover, the fuzzy comprehensive evaluation (I), preference questionnaire (II), and quadratic curvature entropy (III) of the selected combinations are analyzed. Finally, the results of I, II, and III are compared. In conclusion, the three sub-evaluation systems are consistent, which confirms the applicability of the proposed model.

Preventing land desertification is one of the 17 sustainable development goals of the United Nations, which can effectively promote the sustainable development of desert greening. Currently, tree plantation is the most effective way to achieve this goal. However, the existing tree-plantation activities have some imperfections, including low efficiency, labor-intensiveness, challenging environments, and the low survival rate of saplings. Therefore, to contribute to the sustainable development of desert greening, this paper presents a practical desert tree-planting vehicle based on scientific and effective design and evaluation methods. First, based on the survey results, we used the objectives tree method to clarify the design objectives of the tree-planting vehicle. Second, the functional system boundaries of the tree planting vehicle were clarified using the function analysis method. Third, several alternatives were obtained using the finite structure and morphological analysis methods. Finally, an optimal solution was obtained using fuzzy comprehensive evaluation. This optimal design scheme has the characteristics of mechanical automatic planting, a closed cockpit, and large-capacity storage space, which can improve the construction efficiency and labor intensity, thereby contributing to the sustainable development of desert greening.

City bicycles have become popular worldwide because they play an essential role in releasing urban traffic congestion and are environmentally friendly. Since wheelsets are the most prominent shape element in a bicycle, this research explores the influence of various wheel types on the visual image of a city bicycle. First, 10 wheelsets with a high market share in China were selected as the research samples. Meanwhile, vocabularies suitable for describing wheelsets were chosen from many vocabularies. Then, all vocabularies were summarized into six adjectives using factor analysis, and consumers were invited to evaluate all samples using the grouped adjectives. Finally, triangular fuzzy numbers were used to obtain the evaluation scores of 10 wheelsets on six adjectives, and the 10 wheelsets were divided into four groups based on the evaluation scores. The results show that the visual imagery evaluation of the 10 wheelsets had a significant difference in the “trimmed and stable”, “superior and presentable”, and “holistic and balanced” groups, but a slight difference in “novel and individualized”, “rhythmic and metrical”, and “mechanical and ordered.” The research results could serve as a reference for city bicycle operators and help improve product development efficiency, thereby promoting the sustainable development of city bicycles.

With the spread of COVID-19 worldwide, various travel restrictions are becoming a significant trigger for anxiety. Although healing products could relieve anxiety, few scholars have proposed a practical design strategy. Therefore, we offer a design strategy for healing products that includes three phases: preparation, analysis, and verification. In Phase 1, 20 people with moderate or high anxiety are invited to rate 100 samples. Then, FCM is used to obtain representative samples. In Phase 2, a three-layer diagram (incl. the upper, middle, and lower layers) of healing products is obtained using the evaluation grid method. Subsequently, the middle layer is considered evaluation criteria. Additionally, 18 items in the lower layer are considered design guidelines. In Phase 3, we invite two teams to develop innovative designs based on design guidelines and personal experience, generating four alternatives. Finally, four alternatives and four healing commodities are evaluated using grey relation analysis and perceptual questionnaires. The consistency of both evaluations could confirm the validity of the evaluation criteria. The alternatives generated based on the design guidelines are better than other alternatives, demonstrating the effectiveness of the design guidelines. The design strategy is beneficial for developing and evaluating healing products to alleviate people’s anxiety during COVID-19.