1ヶ月以上薬物療法を行い効果の得られなかった反復発作性緊張型頭痛（frequent episodic tension–type headache：

）と慢性TTH（chronic TTH：CTTH）に分類し，鍼治療を行い，Visual Analogue Scale（VAS）による自覚症状の評価が50%以上改善したのを有効として，両群の治療回数・期間について検討した．対象は，TTH221例．82例（男28，女54，平均年齢52.7歳）とCTTH139例（男44，女95，平均年齢50.4歳）である．の有効率80.1%，CTTHの有効率59.9%であり，群の方が有意に高値であった（p＜0.01）．回数・期間は 2.8回14.9日，CTTH8.9回35.9日であり，の方が少ない回数で短期間に改善した（p＜0.01）．は，鍼治療を3回または2週間継続し，さらにCTTHは9回または5週間継続し効果判定する必要性が示された．

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Fiber-to-the-Home () is a technology that enables broadband Internet access through the installation of optical fiber cable between the carrier's central office and the subscribers' premises. It has emerged as the fastest growing broadband access technology in Japan today. Telecommunications carriers are aggressively investing in optical fiber infrastructure mainly in urban areas. The rapid growth, however, is causing concern over the divide between the densely populated areas with access to network and rural areas without, and it is now one of Japan's leading telecommunications policy issues.
At present, the quantitative impact of has not been fully analyzed. It is difficult to evaluate the benefits of from real data because the market conditions of are still rapidly changing. The objective of this study is thus the analysis of the benefit of and the examination of the economic rationale of the initiative of nationwide deployment. Stated Preference (SP) method is applied to collect the data of consumers' preference. Utility function for is estimated by the choice probability model and the marginal willingness to pay (WTP) for the availability of applications, such as digital terrestrial broadcasting, IP telephony and other public services, is computed. Then the consumer surplus of is estimated from the estimation results and, finally, the gross benefit of is compared with the cost that is calculated in the previous study.
As a result of the estimation, the gross annual benefit of ranges from 4,031.6 billion yen (both TV channels and IP telephony service available over ) to 2,457.2 billion yen (TV channels unavailable, only IP telephony available). From the cost benefit analysis in a 20-year time frame, decision variables, such as Net Present Value (NPV), Cost Benefit Ratio (CBR) and Economic Internal Rate of Return (EIRR), seem to be sufficient to support the investment; especially when TV programs are available. However, the assumption of the typical cost benefit analysis, especially the long time frame, is not always realistic in the rapidly changing ICT market. Therefore, we examined the period in which the accumulative benefits need to outweigh the accumulative costs. As a result, it may take 8 to 11 years to balance out the benefits and the costs. To shorten the period, it should be considered to raise the penetration rate and to reduce the development cost. Also, the marginal WTP is calculated in each of five areas with different geographical settings. The respondents in mountain and rural areas indicate higher WTP for the availability of TV channels over . Therefore, it is considered that the transmission of TV channels over may play important roles for raising the penetration rate and expanding the consumer benefit of .
The significance of this paper is the proposal of the practical method of exercising the cost benefit analysis of and its implementation. This study also proposes a means to evaluate the benefits of a rapidly growing telecommunications service in relation to the availability of applications for it. Finally, this paper postulates several broad assumptions required to attain these results.

JEL classification: D12, R11

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This study aims to evaluate the consumer benefits derived from fiber-to-the-home () services that are gaining availability throughout Japan. For this purpose, services were broken down into two parts: infrastructure (hardware) and application (software). First, the Revealed Preference Method based on the data obtained from a questionnaire survey on consumer behaviors concerning Internet usage such as browsing websites and using e-mail was used. The results showed the willingness to pay (WTP) for the infrastructure was 5,198 yen, for the TV service was 1,807 yen, and for IP telephone service was 526 yen. In addition, we found it will take more than 10 years before the total consumer surplus exceeds the total cost if a consumer can not enjoy TV services through under certain conditions. As a result, the application, especially TV services, greatly impact the spread of services in Japan. Although the infrastructure of will be improved in the future, the benefits of applications are thought to be limited and the total benefits of the two parts are lower than expected. Moreover, the tendency that WTP for highland areas is higher than for lowland areas. This may be because other broadband services (e.g. xDSL) can be accessed relatively easily in lowland areas, whereas those services are practically impossible to access in highland areas.

JEL classification: R11, R42, R48

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携帯電話，ブロードバンドといった進展のめざましい通信サービスの普及過程について調査した．先行研究から携帯電話の普及は飽和に近づいていることが分かった．ブロードバンドについては今回の分析により今後も普及が進むと考えられることが分かった．ただし，普及はサービス間で相互の乗り換えをともないながら進展するとみられる．次に，サービスを提供する通信事業会社各社の効率性について分析し，異なるビジネスモデルを持つ通信事業会社の間で効率性・収益性に違いがあるという知見を得た．携帯電話，ブロードバンドサービスなどの普及が進むにつれ，これらを融合したサービスの重要性が高まると考えられる．

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The association for promotion of new generation network services which is an affiliated association of Ministry of Posts and Telecommunications is performing field trials of new generation network services in Kansai Science City near Kyoto. It is called the Pilot Model Project and provides various multimedia service trials such as Video on Demand for about 300 monitor homes through optical fiber distribution systems. Aims of the project are to evaluate technical and operational issues and usefulness of the services.

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This paper provides insights on the status of broadband optical access market and technologies in Europe and on the expected trends for the next generation optical access networks. The final target for most operators, cities or any other player is of course (Fibre To The Home) deployment although we can expect intermediate steps with copper or wireless technologies. Among the two candidate architectures for , PON (Passive Optical Network) is by far the most attractive and cost effective solution. We also demonstrate that Ethernet based optical access network is very adequate to all-IP networks without any incidence on the level of quality of service. Finally, we provide feedback from a pilot network in Colmar (France) based on Gigabit Ethernet PON technology. The interest of this pilot lies on the level of functionality required for broadband optical access networks but also on the development of new home network configurations.

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The spread of optical access broadband networks using Fiber to the Home (

) has not reached the rural areas of developing countries. The current state of global deployment of ICT indicates that it is difficult to sell network systems as stand-alone products due to prohibitive costs, and the demand is for total services that include construction, maintenance, and operation. Moreover, there is a need to offer proposals that include various solutions utilizing broadband networks, as well as for a business model that takes the sustainability of those solutions into consideration. In this paper, we discuss the issues in constructing broadband networks, introduce case studies of solutions using broadband networks for solving social issues in rural areas of developing countries, and discuss the challenges in the deployment of the solutions.

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東日本エリアの戸建て向け

市場は、サービス開始以降、NTT 東日本が高いシェアを維持する一方で参入が十分生起せず、競争が不活性なまま今日に至っている。

本稿では、市場形成を主導する支配的事業者、参入を目論む潜在的競争事業者からなる仮想的

市場を構築し、反事実的想定を含む複数のシナリオに対して、両事業者が「自社の事業価値の最大化に向けてシナリオ選択する」モデルを分析することにより、実際の 市場が競争不活性となったメカニズムについて考察する。

分析結果によれば、NTT 東日本が選択したシナリオにより、潜在的競争事業者の利益が圧迫され、参入障壁が形成されたと考えられる。一方、NTT 東日本のシナリオ選択それ自体は経済合理的であり、行政指導により競争環境の改善が予見されたため、シナリオ変更を必要とする状況には至らなかったと推察される。その結果、参入機会が十分確保できず競争不活性な状態になったと考えられる。

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P2P (Peer-to-Peer) file sharing architectures have scalable and cost-effective features. Hence, the application of P2P architectures to media streaming is attractive and expected to be an alternative to the current video streaming using IP multicast or content delivery systems because the current systems require expensive network infrastructures and large scale centralized cache storage systems. In this paper, we investigate the P2P progressive download enabling Internet video streaming services. We demonstrated the capability of the P2P progressive download in both laboratory test network as well as in the Internet. Through the experiments, we clarified the contribution of the links to the P2P progressive download in the heterogeneous access networks consisting of and ADSL links. We analyzed the cause of some download performance degradation occurred in the experiment and discussed about the effective methods to provide the video streaming service using P2P progressive download in the current heterogeneous networks.

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This paper proposes a dynamic bandwidth allocation algorithm that improves the network performance and bandwidth sharing efficiency in the upstream channels of a hybrid passive optical network (PON) that combines a fiber-to-the-home () access network and wireless sensor networks (WSNs). The algorithm is called the adaptive limited dynamic bandwidth allocation (ALDBA) algorithm. Unlike existing algorithms, the ALDBA algorithm is not limited to controlling just access networks, it also supports WSNs. For the proposed algorithm, we investigate the difference in the lengths of generated data packets between the terminals and sensor nodes of WSN to effectively evaluate the end-to-end average packet delay, bandwidth utilization, time jitter, and upstream efficiency. Two variants of the proposed algorithm and a limited service (LS) scheme, which is an existing well-known algorithm, are compared under non-uniform traffic conditions without taking into consideration priority scheduling. We demonstrate the proposed scheme through simulation by generating a realistic network traffic model, called self-similar network traffic. We conducted a detailed simulation using several performance parameters to validate the effectiveness of the proposed scheme. The results of the simulation showed that both ALDBA variants outperformed the existing LS scheme in terms of average packet delay, bandwidth utilization, jitter, and upstream efficiency for both low and high traffic loads.

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In this paper, we analyze the progressive effects of Information and Communication Technology (ICT) use in terms of regional productivity based on regional economic data. To consider as many factors as possible, we used the Total Factor Productivity (TFP) as the main indicator of productivity. Each Regional TFP index was calculated following the example of Caves-Christensen-Diewert to compare not only differences among prefectures but also time series. The indices showed the progress of ICT use are as follows: the ratio of enterprises in the region using fiber-to-the-home () services (enterprise use), the ratio of enterprises in the region using a network among enterprises (enterprise network use), the regional average of the amount that indicates whether or not enterprises in the region employ a Chief Information Officer (CIO) (CIO establishment), the ratio of enterprises in the region using a telework system (enterprise telework use), the ratio of establishing local public networks in the region (local public network rate), and the ratio of classrooms in the region connected to a LAN (local area network) (LAN classroom rate).
First, we estimated TFP employing the panel instrument variable method, using the panel fixed effect and random effect models, due to the possibility of endogeneity. Second, we employed a two-step system GMM to take into consideration endogeneity, autocorrelation and reverse causality of dependant and explanatory variables.
The results indicate that increased use of ICT has a positive effect on regional productivity. In addition, these results show that not only enterprise ICT use (enterprise use, enterprise network use, CIO establishment and enterprise telework use) but also, through enterprise ICT use, regional informationalization (local public network rate, LAN classroom rate) can have a positive effect on the productivity of regional economies in Japan.
We conclude that a positive attitude toward an informationalized society can have a positive effect on productivity at the prefectural level.

JEL classification: O11, O18, O33, O47, E23

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光ファイバーは将来のわが国産業において極めて重要な位置づけとされるなか，実際どの程度の経済波及効果があるのかを，コブ・ダグラス型生産関数と産業連関表などをモデルとして試算した．結果，直接効果のみを対象とした光ファイバー投資ケースの誘発係数3.93は，一般的な公共インフラ投資や国策で推進されている地上デジタルTV 放送投資に比べてもかなりと高い． また21兆円の投資で562万人，16兆円で同428万人ほどの雇用創出数が期待できることを考慮すると，光ファイバーインフラのわが国産業への寄与が多大であることが改めて確認できた． ところが現段階での光ファイバー整備は民間主体となっており，その整備には限界がある．2005年末にはe-Japan 戦略の総括が行われ，翌年からはポストe-Japan 戦略がスタートする．今のデフレを早急に脱却し，持続的な経済成長と雇用拡大を成し遂げるには，従来の市場競争政策のみに委ねたやり方は再考されるべきであり，国策としての産業政策が同時に求められるところだ．

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