This paper describes concepts and techniques to measure the flexibility of a transportation system to accommodate changing demands and traffic patterns. Flexibility is increasingly desired as a characteristic of transport systems, particularly in light of changes in supply chains and traffic patterns, and the concern for the vulnerability of the system to both natural disasters and terrorist ac...

In this paper we consider a multiple access system with oversaturation of the channel by means of a combined OCDMA/OCDMA scheme with scrambled orthogonal bases. We investigate the performance and the associated maximum channel capacity (channel load) for uncoded BPSK modulation with binary valued chip sequences and optimum multiuser detection for spreading factor N = 4, 8, 16 and 32. It is foun...

The adaptive zero-error capacity of discrete memoryless channels (DMC) with noiseless feedback has been shown to be positive whenever there exists at least one channel output “disprover”, i.e. a channel output that cannot be reached from at least one of the inputs. Furthermore, whenever there exists a disprover, the adaptive zero-error capacity attains the Shannon (small-error) capacity. Here, ...

Various scenarios are considered where some information is more important than other and needs better protection. A general theoretical framework for unequal error protection is developed in terms of exponential error bounds. It provides some fundamental limits and optimal strategies for such problems. New class of message-wise unequal error protection problems are also introduced. Even for dat...

Faced with social and health system capacity constraints and rising and changing demand for welfare services, governments and welfare providers are increasingly relying on innovation to help support and enhance services. However, the evidence reported by several studies indicates that the realization of that potential is not an easy task. Innovations can be deemed inherently complex to implemen...

We take a capacity view of a number of different space-time coding (STC) schemes. While the Shannon capacity of multipleinput multiple-output (MIMO) channels has been known for a number of years now, the attainment of these capacities remains a challenging issue in many cases. The introduction of space-time coding schemes in the last 2–3 years has, however, begun paving the way towards the atta...

The capacity region for the discrete memoryless multipleaccess channel without time synchronization at the transmitters and receivers is shown to be the same as the known capacity region for the ordinary multiple-access channel. The proof utilizes time sharing of two optimal codes for the ordinary multiple-access channel and uses maximum likeliiood decoding over shifts of the hypothesized trans...

あらまし アンテナを空間的に分散させて配置する分散アンテナネットワーク(DAN)は,伝搬損失の影響による 伝送品質の劣化を救済可能な無線ネットワークであり,複数の分散アンテナを用いてダイバーシチを行うことでシ ャドウイング損失および周波数選択性フェージングの影響を低減できるので,さらに伝送品質を改善できる.また, 時空間符号化送受信ダイバーシチ(STBC-JTRD)は符号化率を低下させずに任意の本数の送信アンテナを使用でき, 周波数領域送信等化と併用することで空間ダイバーシチ利得と周波数ダイバーシチ利得の両方を得ることができる. 本論文では,周波数領域(FD-)STBC-JTRD を用いる下りリンクシングルキャリア(SC-)DAN のマルチセル環境下にお けるチャネル容量について検討している.チャネル容量を最大化する送信重みを理論的に導出し,最適送信重みを 用いたときのチャネル容量を...

9 To provide stable and high data rate wireless access for passengers in the train, it is necessary to 10 properly deploy base stations along the railway. We consider this issue from the perspective of service, 11 which is defined as the integral of the time-varying instantaneous channel capacity. With large-scale 12 fading assumption, it will be shown that the total service of each base statio...

In this paper, we address the optimal joint control of inventory and transshipment for a firm that produces in two locations and faces capacity uncertainty. Capacity uncertainty (e.g., due to downtime, quality problems, yield, etc.) is a common feature of many production systems but its effects have not been explored in the context of a firm that has multiple production facilities. We first cha...