The present paper is the first part of a three paper series discussing raceway blockages in blast furnaces for ironmaking. During raceway blockages the hot blast flow rate can be reduced significantly and in such cases it is beneficial to shut down additional fuel systems like pulverized coal injection (PCI) on that specific tuyere. Currently this is mainly done by a simple threshold comparison of the hot blast flow rate data. Using a constant threshold level cannot account for drifting sensor levels or local changes in burden permeability around the raceway. Thus, the authors investigate various strategies to find more reliable solutions for blockage detection and the shutdown of PCI branches. Part 1 discusses the different nature of various blockage events on the basis of tuyere camera images and hot blast flow rate data. For the detailed testing of signal processing (part 2) and image processing algorithms (part 3) a universal test-bench is presented which also includes a common quality assessment of the results. Based on the collection of tuyere camera images a simple classification of blockage events is established. The analysis of 1500 hours of blast furnace operation data delivers a proper statistics about the frequency of occurrence of blockages on a small size blast furnace. The detailed analysis of hot blast signals and tuyere camera images presented in this paper series aims to improve the understanding of the raceway regions and their influence on optimal blast furnace operation.

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　This paper first examines the advantages and disadvantages of multiple-choice and open-ended questions. It highlights a major merit of open-ended questions, namely that they can be used to assess the problem-solving and thinking abilities to be tested in mathematics tests. We then argue for the increased use of open-ended questions in mathematics tests, especially in the National Center Test for University Admissions (Center Test). In the latter part of the article, we investigate reasons open-ended questions have not been extensively used in large-scale examinations and possible public reactions toward introducing this question type in the Center Test. The previous literature and surveys suggest that the manual, labor-intensive, and subjective nature of scoring open-ended questions has been an obstacle to large-scale use; that most universities think open-ended questions are necessary and possible; and that a precedent exists that can be imitated in the exam for Chinese high school graduates called “Gao Kao.” Based on the information gathered, we present our opinions on feasible measures in Japan to improve the new exam being implemented starting in 2020. Specifically, we argue that the new exam should consist of more open-ended questions than in the pre-test, which demonstrated a prototype of the new exam. Furthermore, we emphasize that such questions should be completely open-ended rather than provide blanks to fill out so as to enable universities to learn about examinees’ thinking processes and their ability to construct solutions on their own.

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In this paper, we proposed reduction operators of timed Petri net for efficient model checking. Timed Petri nets are used widely for modeling and analyzing systems which include time concept. Analysis of the system can be done comprehensively with model checking, but there is a state-space explosion problem. Therefore, previous researchers proposed reduction methods and translation methods to timed automata to perform efficient model checking. However, there is no reduction method which consider observability and there is a trade-off between the amount of description and the size of state space. In this paper, first, we have defined a concept of timed behavioral inheritance. Next, we have proposed reduction operators of timed Petri nets based on timed behavioral inheritance. Then, we have applied our proposed operators to an artificial timed Petri net. Moreover, the results show that the reduction operators which consider observability can reduce the size of state space of the original timed Petri nets within the experiment.

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Shared-Memory Optical Packet (SMOP) switch architecture is very promising for significantly reducing the amount of required optical memory, which is typically constructed from fiber delay lines (FDLs). The current reservation-based scheduling algorithms for SMOP switches can effectively utilize the FDLs and achieve a low packet loss rate by simply reserving the departure time for each arrival packet. It is notable, however, that such a simple scheduling scheme may introduce a significant packet out of order problem. In this paper, we first identify the two main sources of packet out of order problem in the current reservation-based SMOP switches. We then show that by introducing a “last-timestamp” variable and modifying the corresponding FDLs arrangement as well as the scheduling process in the current reservation-based SMOP switches, it is possible to keep packets in-sequence while still maintaining a similar delay and packet loss performance as the previous design. Finally, we further extend our work to support the variable-length burst switching.

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When accurately quantifying convective heat exchange between the human body and the surrounding environment, mean skin temperature is determined by measuring the skin temperature of areas of the body surface exposed to airflow (hereinafter referred to as the convective heat transfer area) and then calculating the ratio of the convective heat transfer area with the uniform skin temperature to the total convective heat transfer area. Thus we must consider convective heat transfer areas to determine mean skin temperature. In this study, the convective heat transfer area of the human body in two basic postures (standing on the floor and sitting on a chair) was measured by dividing the body surface into smaller sections. We then proposed weighting coefficients for calculating mean skin temperature taking into account convective heat transfer areas, and conducted experiments to clarify how convective heat transfer areas affected calculations of mean skin temperature. The results showed that, for both standing and sitting positions, due to the areas of contact between two body surfaces and between the body and the floor, the convective heat transfer area for the hand and foot regions was markedly small. We then calculated weighting coefficients for calculating mean skin temperature that take into account convective heat transfer areas for standing and sitting positions. The tendency was that the smaller the ratio of convective heat transfer area to the total body surface area, the greater the difference in mean skin temperature using the Hardy-DuBois technique. The results of the present study also clarify that by taking into account convective heat transfer areas, the skin temperature of the extremities can be reflected in mean skin temperature for both standing and sitting positions.

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The validity of age determination of the Japanese charr Salvelinus leucomaenis using scale readings was examined by the mark and recapture method in a Japanese mountain stream from 1986 to 1989. When recaptured within a year, all of the 3 (1 growth and 2 resting) scale zone fish were found to still have 3 zones on their scales. One year after marking, they had 4 (2 growth and 2 resting) or 5 (3 growth and 2 resting) zones on their scales and after 2 years, they still had 4 or 5 zones. Fish with 1 resting zone, i.e., 1 annulus, were regarded as age 1⁺ and fish with 2 annuli were regarded as age 2⁺. Consequently, age determination of the Japanese charr using scales might be reliable to 1⁺ age but doubtful for 2⁺ and older.

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Cluster tools are widely used for semiconductor manufacturing. A multi-cluster tool consists of several single cluster tools which are interconnected with each other. The multi-cluster tool causes a deadlock due to non-existence of intermediate buffer. Deadlock is a serious problem leading decrease of throughput and deterioration of wafers. In this paper, the optimal supervisor proposed by Chen et al. (2011) is applied to a Petri net model of the multi-cluster tools. From the comparison of performance with the conventional deadlock prevention policies, we find that the maximally permissive supervisor does not always produce a better scheduling performance. We propose a design method of a Petri net supervisor to improve the scheduling performance. Our main idea is to eliminate legal markings that may eventually cause the increase of makespan. The proposed method is applied to the two-connected multi-cluster tool. The results indicate that the scheduling performance can be improved by the proposed method without lowering maximal permissivity.

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[Purpose] To establish the test-retest reliability of an iPhone application and determine the immediate effect of motor control exercise (MCE) on lumbar position sense. [Participants and Methods] This study used a two-arm, randomized controlled trial design with a blinded assessor. Sixty healthy participants were randomized into the exercise or control group. The exercise group underwent 30-min MCE, whereas the control group rested for 15 min. Lumbar motion measured by two iPhones with goniometer application was used to determine the test-retest reliability. Absolute repositioning errors (pre- and post-test) from the control and exercise groups were used to determine the immediate effect of MCE on lumbar position sense. [Results] The test-retest reliability was 0.67–0.95. A significant interaction effect was found for Angle*Time, main effect of Angle, and main effect of Time. Post-hoc comparison showed a significant improvement in position sense at 45° and 60° in the exercise group. [Conclusion] The findings suggest that a mobile phone application has the ability to detect changes in lumbar position sense between sessions that exceed measurement error following MCE. One session of specific MCE can improve lumbar position sense at high lumbar flexion.

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ECN, as a decisive approach for TCP congestion control, has been proposed for many years. However, its deployment on the Internet is much slower than expected. In this paper, we investigate the state of the deployment of ECN (Explicit Congestion Notification) on the Internet from a different viewpoint. We use the data set of web domains published by Alexa as the hosts to be tested. We negotiate an ECN-Capable and a Not ECN-Capable connections with each host and collect all packets belonging to the connections. By analyzing the header fields of the TCP/IP packets, we dig out the deployment rate, connectivity, variation of round-trip time and time to live between the Not ECN-Capable and ECN-Capable connections as well as the rate of IPv6-Capable web servers. Especially, it is clear that the connectivity is different from the domains (regions on the Internet). We hope that the findings acquired from this study would incentivize ISPs and administrators to enable ECN in their network systems.

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Heritabilities, and genetic and phenotypic correlations were estimated for total length, body weight, body depth, and head length of masu salmon Oncorhynchus masou. During 4 month period after first starting to feed in juveniles, 20 full-sib and 10 half-sib families were reared separately and each family was given environmental conditions as equal as possible. Data were collected at 4 months and 8 months of age by individual tagging with fin cut 1994. The same experiments using colored fluorescent elastomer tags as family markers were repeated in 1995. Overall survivals in the study varied among each family. The heritabilities of growth related traits estimated for sire components (in 1994 and 1995) at 4 months age were found to be quite high: ranging between 0.35 and 0.47 in total length. Estimated heritabilities at 8 months age in each year ranged from 0.18 and 0.42 in total length. Similar values were obtained in the other three related areas of body weight, body depth and head length. Genetic and phenotypic correlations among the growth traits were all positively high. Genetic variations in body weight were found to be remarkably high, about three times as high as that in the total length of the masu salmon. Phenotypic correlations between 4 and 8 month ages were 0.45-0.63. Selective breeding in growth related traits would be effective in masu salmon culture.

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Legally provided surface parking lots were merely not sufficient to accommodate the current demand for parking inside the Malabe campus, SLIIT tempting commuters to park in illegal areas and student playground of the campus. Therefore, this study evaluated the operational and safety issues of the existing facility by means of four surveys. Parking inventory survey was conducted to enumerate existing parking facility and its characteristics. Using a Metro Count roadside unit, vehicle inflow-outflow data were obtained through six months to study parking accumulation characteristics. Vehicle count surveys were conducted to determine parking characteristics such as parking accumulation profile, parking demand, number of users, average parking durations and turnover. Feedback from users regarding parking problem was collected from interview survey. Recommendations were proposed to supply total parking spaces for 399 cars, 365 bikes and 10 buses to meet the demand in 2025 while ensuring the safety and efficiency of parking.

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Since the mid-1970s, all land in Ethiopia has officially been declared as a public/state property. Consequently, peasants have enjoyed only land use rights, while land sale has been deemed illegal. Indeed, the government legislation is not the only factor to have constrained land sale in the study area. The Arsii Oromo customs too discourage the transfer of land to ‘outsiders.’ Nevertheless, neither government legislation nor the local customs have exercised an absolute control over land sale, and small-scale land transactions have existed under various disguises. Although most of the land sale, being an illicit practice, is conducted through oral agreements, some land transactions involve informal written papers. At a glance these written materials appear to be attempts to ‘formalize’ an informal activity. Closer examination, however, reveals how some important words are carefully avoided, and other words and concepts with ambiguous or dual meanings are being deliberately employed in these written deals. These disguises and ambiguities introduced into the written agreements demonstrate farmers’ ‘adaptive strategies’ (adaptation both to the policies/legislation, and to the local customs as well) in order to conduct land transactions. Detailed analysis of these informal recordings is the core focus of this paper.

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It is a fashion to use the manycore accelerators to promote the computing power in a computing plat- form. Especially GPU is one of the main series of the high performance computing, which is also employed by top supercomputers in the world. Programming methods on such accelerators includes development of control programs which accelerators executes to schedule the invocation of the accelerator’s kernel program. The kernel program needs to be written based on the stream computing paradigm. Connecting I/Os of the kernel programs, we can develop a large application. When we consider the processing flow as a directed graph, we can implement a GUI-based programming tool for the accelerators. It visualizes a pipeline-based processing flow. However, it is very hard to find a starting point of a complex processing flow. Moreover, although the processing pipeline include the potential parallelism, it is hard for the programmer to exploit it intuitively. This paper proposes an algorithm applying the spanning tree that mechanically exploits the parallelism and determines an execution order. To verify the algorithm, this paper performs evaluation with realistic applications. The algorithm exploits effectively the parallelism and construct the optimal pipeline processing flow.

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The working space environment has a large impact on workers. To improve workplace productivity, it is important to design the office environment. In this paper, we focused on radiant air conditioning, which is attracting increasing attention for use in offices. The purpose of this study was to determine the differences in indoor environment between radiant air conditioning and convective air conditioning and evaluate their effects on workplace productivity by conducting subject experiments.

Radiant air conditioning was found to reduce differences between deep body temperature and terminal skin temperature and to improve creative work performance compared with convection air conditioning.

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