This study developed a new walker with improved operability for 3-9-year-old children with cerebral palsy（Gross Motor Function Classification System level Ⅲ） and verified its validity. Although numerous walkers are available, their operability is suboptimal. The proposed six-wheel walker was classified as a posterior walker. To verify its validity, we selected three tasks that are frequently performed during daily activities: walking straight on a flat surface, walking up and down a step like the curb on the street, and turning left and right at a right angle. Five children were included, and they performed the three tasks using the proposed walker and a Posture Control Walker（PCW）, which is the most commonly used commercial walker. Time to walk a 5-m distance in the middle of each task was measured. Our results revealed that the walking time with the proposed walker in the step task in three children and in the turn task in four children was shortened because of the improved operability by a series of actions that required lifting only the front wheels to turn our whole walker. These results suggest that the proposed walker is easier to operate and more effective in assisting walking than PCW.

This study investigated the factors related to the following three outcomes among authors who have submitted their articles to the Japanese Journal of Ergonomics: （1） Satisfaction; （2） Willingness; and （3）Recommendation. An online survey was conducted among 124 corresponding authors who had submitted articles to the journal in the past five years（66 respondents, response rate: 53.2％）. A 9-point Likert scale was used for each outcome, which was re-categorized into three levels（low, medium, and high）and cross-tabulated with each factor. Fisher's exact test, Cramer's V for effect size, and multiple correspondence analysis were used to evaluate the association. The results showed that the factors common to the three outcomes were: the quality of the editor's comments（ps＜0.01, V＝0.38-0.53, df＝4）, the quality of the reviewer's comments（ps ≤ 0.01, V＝0.31-0.40, df＝4）, and the decision of acceptance/rejection（ps ≤ 0.01, V＝0.35-0.46, df＝4）. This study, thus, revealed the main factors involved in the levels of satisfaction, willingness, and recommendation when submitting articles for publication in the Japanese Journal of Ergonomics.

In modern society, customer needs are becoming more complex, and the values of products and services are becoming more complex as well. To accurately capture customer needs and effectively propose complex products and services, many companies in the corporate sales department are more likely to have multiple sales representatives specializing in specific fields to compose as a sales force （sales team）. Even though it is a big concern for the company whether it is possible to demonstrate outstanding results in sales team, the factors that affect the performance of sales force have not been clarified. In this study, conducted a questionnaire survey for a wide range of sales representatives based on hypothetical model, comparison between hypothetical model and performance model, benchmarked individual sales representatives and sales force through analysis by multivariate analysis and clarified performance factors that are specific to sales force. The main achievement of this study is to clarify relationship between the three factors that “Sincere and positive sales activities and attitudes for each team members”, “Share information clarity and effectively in sales team” and “sales performance”.

We investigated the effect of force level condition before controlling on the characteristics for force generation using graded isometric contractions of the knee extensors. Participants performed the following grading tasks as quickly and accurately as possible. From baseline of 0％ MVC, force was increased to the target force levels of 20％, 40％ and 60％ MVC. From baseline of 10％ MVC, force was increased to the target force levels of 30％, 50％ and 70％ MVC. We compared the conditions （baseline; 0％ and 10％） and magnitudes of force level （magnitudes between the target level and baseline; 20％, 40％ and 60％）. The following parameters of the recorded force were calculated for analysis: point of accuracy （constant error, absolute error）, reproducibility （variable error）, and quickness （reaction time, adjustment time, and rate of force development）. As a results, the errors as accuracy were no difference between two conditions. The reaction time as quickness was shorter for 10％ MVC than 0％ MVC baseline condition in 20％ and 40％ magnitudes. These results suggested that the characteristics of quickness, especially in starting to adjustment, was affected by the force level condition before controlling.

The memory strategies that the children employ to search for an icon on a computer screen were investigated based on the process of short-term memory development. The participants included twenty 4-year-old and nineteen 6-year-old children, as well as 10 adults. Two types of icon patterns were used in the experiment: “meaningful” and “meaningless” figures. The study participants were asked to select a target item from icons randomly arrayed on the computer screen. The success rate and selection time served as a measure of performance and these results improved with old groups. The 4-year-old children were supposed to have difficult rehearsal strategies; however, they were able to apply it. The 6-year-old children could apply the rehearsal strategy, but used the image strategy in the experiment with “meaningless” figures since it is difficult to change the picture to words. Moreover the 4- and 6 years old children showed difficulty in using the memory strategies effectively when compared to adults.