start-ver=1.4 cd-journal=joma no-vol=8 cd-vols= no-issue=1 article-no= start-page=50 end-page=58 dt-received= dt-revised= dt-accepted= dt-pub-year=2018 dt-pub=20180410 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=A holding access-point assignment algorithm for IEEE802.11 wireless local-area networks en-subtitle= kn-subtitle= en-abstract= kn-abstract= Nowadays, various types of access-points (APs) and hosts such as dedicated APs, laptop personal computers (PCs), and mobile terminals have been used in IEEE802.11 wireless local-area networks (WLANs). As a result, the optimal assignment of holding APs with different types into the network field, depending on the host type distribution, has become another important task to design high-performance WLANs. In this paper, we first define this holding access-point assignment problem as a combinatorial optimisation problem and propose its two-phase heuristic algorithm. Then, since plural partially overlapping channels are available in IEEE802.11 WLANs, we present the channel assignment extension to the APs such that the communication time of the APs is minimised, and the model to estimate the communication time increase by interferences. The effectiveness of our proposal is verified through simulations in six instances using the WIMNET simulator. en-copyright= kn-copyright= en-aut-name=TajimaShigeto en-aut-sei=Tajima en-aut-mei=Shigeto kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=FunabikiNobuo en-aut-sei=Funabiki en-aut-mei=Nobuo kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=HigashinoTeruo en-aut-sei=Higashino en-aut-mei=Teruo kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= affil-num=1 en-affil= kn-affil=Graduate School of Engineering Science, Osaka University affil-num=2 en-affil= kn-affil=Graduate School of Natural Science and Technology, Okayama University affil-num=3 en-affil= kn-affil=Graduate School of Information Science and Technology, Osaka University en-keyword=wireless local-area network kn-keyword=wireless local-area network en-keyword=WLAN kn-keyword=WLAN en-keyword=holding access-point kn-keyword=holding access-point en-keyword=partially overlapping channel kn-keyword=partially overlapping channel en-keyword=assignment algorithm kn-keyword=assignment algorithm en-keyword=combinatorial optimisation problem kn-keyword=combinatorial optimisation problem END start-ver=1.4 cd-journal=joma no-vol=7 cd-vols= no-issue=3 article-no= start-page=145 end-page=154 dt-received= dt-revised= dt-accepted= dt-pub-year=2017 dt-pub=20171229 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=A design-aware test code approach for code writing problem in Java programming learning assistant system en-subtitle= kn-subtitle= en-abstract= kn-abstract= To advance Java programming educations, we have developed the web-based Java programming learning assistant system (JPLAS) that provides the code writing problem. This problem asks a student to write a source code for a given assignment, where the correctness is verified by running the test code on JUnit. In this paper, we propose a design-aware test code approach for the code writing problem. The design-aware test code tests any important method in the model source code that has the advisable design for the assignment. Thus, by writing a code that can pass it, a student is expected to implement the code with the proper classes/methods in the model code. In evaluations of the proposal, all the students could complete highly qualitative codes for five graph algorithms using the design-aware test codes, where the code quality metrics were measured by metrics plugin for Eclipse. en-copyright= kn-copyright= en-aut-name=Khin Khin Zaw en-aut-sei=Khin Khin Zaw en-aut-mei= kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=FunabikiNobuo en-aut-sei=Funabiki en-aut-mei=Nobuo kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= affil-num=1 en-affil=Graduate School of Natural Science and Technology, Okayama University kn-affil= affil-num=2 en-affil=Graduate School of Natural Science and Technology, Okayama University kn-affil= en-keyword=Java programming learning assistant system kn-keyword=Java programming learning assistant system en-keyword=JPLAS kn-keyword=JPLAS en-keyword=design-aware test code kn-keyword=design-aware test code en-keyword=JUnit kn-keyword=JUnit en-keyword=metric plugin kn-keyword=metric plugin en-keyword=breadth-first-search kn-keyword=breadth-first-search en-keyword=BFS kn-keyword=BFS END