著者

Jong-Kwang KIM Seung-Jin CHOI Young-Hwan YOU Hyoung-Kyu SONG

出版者

The Institute of Electronics, Information and Communication Engineers

雑誌

IEICE TRANSACTIONS on Communications (ISSN:09168516)

巻号頁・発行日

vol.E101-B, no.12, pp.2445-2452, 2018-12-01

被引用文献数

1

---

Multiple input multiple output with orthogonal frequency division multiplexing (MIMO-OFDM) is used in various parts of wireless communication systems. Because the MIMO-OFDM system simultaneously transmits parallel data streams and each receive antenna receives all data streams at one time, the detection ability of the receiver is very important. Among the detection schemes suitable for OFDM, maximum likelihood (ML) detection has optimal performance, but its complexity is so high that it is infeasible. Linear detection schemes such as zero-forcing (ZF) and minimum mean square error (MMSE) have low complexity, but also low performance. Among non-linear detection schemes, the near-ML detection which is the sphere detection (SD) or the QR decomposition with M algorithm (QRD-M) also has optimal performance but the complexity of SD and QRD-M detection is also too high. Other non-linear detection schemes like successive interference cancellation (SIC) detection have low complexity. However, the performance of SIC detection is lower than other non-linear detection schemes. In this paper, selectively iterative detection is proposed for MIMO-OFDM system; it offers low complexity and good performance.

著者

Kazuhiko KINOSHITA Shu NISHIKORI Yosuke TANIGAWA Hideki TODE Takashi WATANABE

出版者

The Institute of Electronics, Information and Communication Engineers

雑誌

IEICE Transactions on Communications (ISSN:09168516)

巻号頁・発行日

pp.2019EBP3080, (Released:2019-09-03)

被引用文献数

2

---

Coexistence between ZigBee and Wi-Fi technologies, which operate within the same frequency band, is increasing with the widespread use of the IoT (Internet of Things). ZigBee devices suffer significant decreases in the sink arrival rate of packets in the presence of Wi-Fi interference. To overcome this problem, many channel control methods have been proposed. These methods switch only ZigBee channels to avoid interference withWi-Fi. In contrast, we propose a cooperative channel control method for improving ZigBee packet arrival rate by controlling both the Wi-Fi and ZigBee channels. Specifically, the proposed method not only controls ZigBee devices and channels but also requests a temporary pause in the use of specific Wi-Fi channels. Finally, computer simulations show the effectiveness of the proposed method from the viewpoints of ZigBee's packet arrival rate and applications' satisfaction. In addition, the feasibility of the proposed method is also confirmed by experiments with prototyping.

著者

Takamasa OCHIAI Kohei MATSUEDA Takao KONDO Hiroaki TAKANO Ryota KIMURA Ryo SAWAI Fumio TERAOKA

出版者

The Institute of Electronics, Information and Communication Engineers

雑誌

IEICE TRANSACTIONS on Communications (ISSN:09168516)

巻号頁・発行日

vol.E102-B, no.8, pp.1649-1659, 2019-08-01

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In LTE (Long Term Evolution) / LTE-Advanced (LTE-A) system, the user-plane for a user equipment (UE) is provided by tunneling, which increases header overhead, processing overhead, and management overhead. In addition, the LTE-A system does not support moving cells which are composed of a mobile Relay Node (RN) and UEs attached to the mobile RN. Although there are several proposals for moving cells in the LTE-A system and the 5G system, all of them rely on tunneling for the user-plane, which means that none of them avoid the tunneling overheads. This paper proposes MocLis, a moving cell support protocol based on a Locator/ID split approach. MocLis does not use tunneling. Nested moving cells are supported. Signaling cost for handover of a moving cell is independent of the number of UEs and nested RNs in the moving cell. A MocLis prototype, implemented in Linux, includes user space daemons and modified kernel. Measurements show that the attachment time and handover time are short enough for practical use. MocLis has higher TCP throughput than the tunneling based approaches.

著者

SEO Won-Kyeong CHOI Jae-In CHO You-Ze

出版者

一般社団法人 電子情報通信学会

雑誌

IEICE Transactions on Communications (ISSN:09168516)

巻号頁・発行日

vol.97, no.11, pp.2327-2336, 2014

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The Internet Engineering Task Force (IETF) has been actively standardizing distributed mobility management (DMM) schemes with multiple Mobility Anchors (MAs). Yet, all existing schemes have limitations that preclude the efficient distribution of mobile data traffic, including single point failure problems, heavy tunneling overheads between MAs, and a restrictive traffic distribution for external nodes in a mobility domain. Therefore, this paper proposes an efficient mobility management scheme with a virtual Local Mobility Anchor (vLMA). While the vLMA is designed assuming multiple replicated LMAs for a PMIPv6 domain, it acts virtually as a single LMA for the internal and external nodes in the PMIPv6 domain. Furthermore, the vLMA distributes mobile data traffic using replicated LMAs, and routes packets via a replicated LMA on the optimal routing path. Performance evaluations confirm that the proposed scheme can distribute mobile data traffic more efficiently and reduce the end-to-end packet delay than the Distributed Local Mobility Anchor (DLMA) and the Proxy Mobile IPv6 (PMIPv6).

著者

Doohwan LEE Hirofumi SASAKI Hiroyuki FUKUMOTO Ken HIRAGA Tadao NAKAGAWA

出版者

The Institute of Electronics, Information and Communication Engineers

雑誌

IEICE Transactions on Communications (ISSN:09168516)

巻号頁・発行日

vol.E100.B, no.7, pp.1044-1063, 2017-07-01 (Released:2017-07-01)

参考文献数

60

被引用文献数

72

---

This paper explores the potential of orbital angular momentum (OAM) multiplexing as a means to enable high-speed wireless transmission. OAM is a physical property of electro-magnetic waves that are characterized by a helical phase front in the propagation direction. Since the characteristic can be used to create multiple orthogonal channels, wireless transmission using OAM can enhance the wireless transmission rate. Comparisons with other wireless transmission technologies clarify that OAM multiplexing is particularly promising for point-to-point wireless transmission. We also clarify three major issues in OAM multiplexing: beam divergence, mode-dependent performance degradation, and reception (Rx) signal-to-noise-ratio (SNR) reduction. To mitigate mode-dependent performance degradation we first present a simple but practical Rx antenna design method. Exploiting the fact that there are specific location sets with phase differences of 90 or 180 degrees, the method allows each OAM mode to be received at its high SNR region. We also introduce two methods to address the Rx SNR reduction issue by exploiting the property of a Gaussian beam generated by multiple uniform circular arrays and by using a dielectric lens antenna. We confirm the feasibility of OAM multiplexing in a proof of concept experiment at 5.2 GHz. The effectiveness of the proposed Rx antenna design method is validated by computer simulations that use experimentally measured values. The two new Rx SNR enhancement methods are validated by computer simulations using wireless transmission at 60 GHz.

著者

Hideki KIRINO Kazuhiro HONDA Kun LI Koichi OGAWA

出版者

The Institute of Electronics, Information and Communication Engineers

雑誌

IEICE Transactions on Communications (ISSN:09168516)

巻号頁・発行日

vol.E101.B, no.2, pp.349-356, 2018-02-01 (Released:2018-02-01)

参考文献数

15

被引用文献数

1

---

A new Waffle-iron Ridge Guide (WRG) structure that has the ability to control both wavelength and impedance is proposed. With the proposed structure, not only can the wavelength be controlled over a wide range for both fast- and slow-waves in free space but the impedance can also be controlled. These features can improve the performance of array antennas in terms of reducing grating lobes and side lobes. In this paper, we discuss and evaluate a design scheme using equivalent circuits and EM-simulation. This paper also discusses how the conductivity and dielectric loss in the WRG affect the total gain of the array antenna.

著者

Akira TAKAHASHI Takanori HAYASHI

出版者

The Institute of Electronics, Information and Communication Engineers

雑誌

IEICE Transactions on Communications (ISSN:09168516)

巻号頁・発行日

vol.E100.B, no.9, pp.1554-1563, 2017-09-01 (Released:2017-09-01)

参考文献数

23

被引用文献数

2

---

We propose a framework called “QoE-centric Service Operation,” with which we attempt to implement a means to enable the collaboration of end-users, service providers, and network providers to achieve better QoE of telecommunication services. First, we give an overview of the transition in the quality factors of voice, video, and web-browsing applications. Then, taking into account the fact that many quality factors exist not only in networks, but also in servers and terminals, we discuss how to measure, assess, analyze, and control QoE and the technical requirements in each component. We also propose approaches to meet these requirements: packet- and KPI-based QoE estimation, compensation of sparse measurement, and quality prediction based on human behavior and traffic estimation. Finally, we explain the results of our proof-of-concept study using an actual video delivery service in Japan.

著者

Akihiro NAKAO Ping DU

出版者

The Institute of Electronics, Information and Communication Engineers

雑誌

IEICE Transactions on Communications (ISSN:09168516)

巻号頁・発行日

vol.E101.B, no.7, pp.1536-1543, 2018-07-01 (Released:2018-07-01)

参考文献数

29

被引用文献数

28

---

In this paper, we posit that, in future mobile network, network softwarization will be prevalent, and it becomes important to utilize deep machine learning within network to classify mobile traffic into fine grained slices, by identifying application types and devices so that we can apply Quality-of-Service (QoS) control, mobile edge/multi-access computing, and various network function per application and per device. This paper reports our initial attempt to apply deep machine learning for identifying application types from actual mobile network traffic captured from an MVNO, mobile virtual network operator and to design the system for classifying it to application specific slices.

著者

Hiroki WATANABE Takao KONDO Kunitake KANEKO Fumio TERAOKA

出版者

The Institute of Electronics, Information and Communication Engineers

雑誌

IEICE TRANSACTIONS on Communications (ISSN:09168516)

巻号頁・発行日

vol.E101-B, no.9, pp.1967-1981, 2018-09-01

---

Recently, application demands placed on the network have become more multifaceted. Highly functional application-to-application communication services such as bandwidth aggregation, fault tolerant communication, and delay/disruption tolerant networking (DTN) were developed independently in the network layer, the transport layer, and the application layer. As a result, protocol layering has become complicated. This paper proposes to insert Layer-5 (L5) between the application layer and the transport layer to separate communication policies and communication mechanisms to make protocol layering clearer. The transport layer (L4) provides end-to-end communication mechanisms such as reliable byte stream while L5 realizes communication policies such as bandwidth aggregation by combining the communication mechanisms in L4. This paper proposes five types of L5-paths as communication policies: (1) the L5 bundled path for bandwidth aggregation or fault tolerant communication, (2) the L5 spatially-spliced path for communication with middleboxes, (3) the L5 temporally-spliced path for DTN, (4) the L5 spliced-bundled path, and (5) the L5 bundled over spatially-spliced path. An application can select and use an appropriate L5-path depending on the network circumstances through a common API. A prototype of L5 is implemented in the Linux user space as a library to make deployment and maintenance easier. An evaluation shows that establishment time of L5-paths is short enough and performance of L5-paths is comparable or superior to existing technologies.

著者

KANG Chang Soon KIM Junsu SUNG Dan Keun

出版者

一般社団法人 電子情報通信学会

雑誌

IEICE transactions on communications (ISSN:09168516)

巻号頁・発行日

vol.92, no.6, pp.2327-2331, 2009-06-01

参考文献数

14

被引用文献数

2

---

Mutual interference among users can abruptly increase othercell interference and cause overload situation in coexisting WCDMA and HSDPA systems. Traffic overloading can degrade the performance of the systems. This letter proposes a new dynamic downlink load control (DDLC) algorithm to reduce performance degradation due to overload in the coexistence of WCDMA and HSDPA systems. With the proposed algorithm, the downlink load is controlled according to load states classified by two load-control thresholds, and traffic overloading is alleviated by dynamically adjusting the CQI values reported by users, based on the downlink load as well as channel variations. The proposed algorithm is simulated and results show that the DDLC scheme improves the performance of both WCDMA and HSDPA systems in terms of outage probability, total system throughput, and radio resource utilization.

著者

TAKANO Chisa AIDA Masaki

出版者

一般社団法人電子情報通信学会

雑誌

IEICE transactions on communications (ISSN:09168516)

巻号頁・発行日

vol.88, no.4, pp.1559-1567, 2005-04-01

参考文献数

13

被引用文献数

11

---

We have proposed diffusion-type flow control as a solution for the extremely time-sensitive flow control required for high-speed networks. In our method of flow control, we design in advance simple and appropriate rules for action at the nodes, and these automatically result in stable and efficient network-wide performance through local interactions between nodes. Specifically, we design the rules for the flow control action of each node that simulates the local interaction of a diffusion phenomenon, in order that the packet density is diffused throughout the network as soon as possible. However, in order to make a comparison with other flow control methods under the same conditions, the evaluations in our previous studies used a closed network model, in which the number of packets was unchanged. This paper investigates the performance of our flow control method for an end-to-end flow, in order to show that it is still effective in more realistic networks. We identify the key issues associated with our flow control method when applied to an open network model, and demonstrate a two-step solution. First, we consider the rule for flow control action at the boundary node, which is the ingress node in the network, and propose a rule to achieve smooth diffusion of the packet density. Secondly, we introduce a shaping mechanism, which keeps the number of packets in the network at an appropriate level.

著者

Zhangjie FU Xingming SUN Qi LIU Lu ZHOU Jiangang SHU

出版者

The Institute of Electronics, Information and Communication Engineers

雑誌

IEICE TRANSACTIONS on Communications (ISSN:09168516)

巻号頁・発行日

vol.E98-B, no.1, pp.190-200, 2015-01-01

---

Cloud computing is becoming increasingly popular. A large number of data are outsourced to the cloud by data owners motivated to access the large-scale computing resources and economic savings. To protect data privacy, the sensitive data should be encrypted by the data owner before outsourcing, which makes the traditional and efficient plaintext keyword search technique useless. So how to design an efficient, in the two aspects of accuracy and efficiency, searchable encryption scheme over encrypted cloud data is a very challenging task. In this paper, for the first time, we propose a practical, efficient, and flexible searchable encryption scheme which supports both multi-keyword ranked search and parallel search. To support multi-keyword search and result relevance ranking, we adopt Vector Space Model (VSM) to build the searchable index to achieve accurate search results. To improve search efficiency, we design a tree-based index structure which supports parallel search to take advantage of the powerful computing capacity and resources of the cloud server. With our designed parallel search algorithm, the search efficiency is well improved. We propose two secure searchable encryption schemes to meet different privacy requirements in two threat models. Extensive experiments on the real-world dataset validate our analysis and show that our proposed solution is very efficient and effective in supporting multi-keyword ranked parallel searches.

著者

Maziar NEKOVEE Yinan QI Yue WANG

出版者

一般社団法人 電子情報通信学会

雑誌

IEICE Transactions on Communications (ISSN:09168516)

巻号頁・発行日

vol.E100.B, no.8, pp.1181-1189, 2017-08-01 (Released:2017-08-01)

参考文献数

25

被引用文献数

10

---

In order to support user data rates of Gbps and above in the fifth generation (5G) communication systems, millimeter wave (mm-wave) communication is proposed as one of the most important enabling technologies. In this paper, we consider the spectrum bands shared by 5G cellular base stations (BS) and some existing networks, such as WiGig and proposed a method for spectrally efficient coexistence of multiple interfering BSs through adaptive self-organized beam scheduling. These BSs might use multiple radio access technologies belonging to multiple operators and are deployed in the unlicensed bands, such as 60GHz. Different from the recently emerging coexistence scenarios in the unlicensed 5GHz band, where the proposed methods are based on omni-directional transmission, beamforming needs to be employed in mm-wave bands to combat the high path loss problem. The proposed method is concerned with this new scenario of communication in the unlicensed bands where (a) beam-forming is mandatory to combat severe path loss, (b) without optimal scheduling of beams mutual interference could be severe due to the possibility of beam-collisions, (c) unlike LTE which users time-frequency resource blocks, a new resource, i.e., the beam direction, is used as mandatory feature. We propose in this paper a novel multi-RAT coexistence mechanism where neighbouring 5G BSs, each serving their own associated users, schedule their beam configurations in a self-organized manner such that their own utility function, e.g. spectral efficiency, is maximized. The problem is formulated as a combinatorial optimization problem and it is shown via simulations that our proposed distributed algorithms yield a comparable spectral efficiency for the entire networks as that using an exhaustive search, which requires global coordination among coexisting RATs and also has a much higher algorithmic complexity.

著者

MOON Jin-Seob JEON Joo-Seong

出版者

一般社団法人電子情報通信学会

雑誌

IEICE transactions on communications (ISSN:09168516)

巻号頁・発行日

vol.86, no.10, pp.2975-2981, 2003-10-01

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Direct conversion techniques commonly used for the transmitter in basestation rely on analog performance of the quadrature modulator. In this paper, simulated results show that imperfections in analog quadrature modulation gain and phase error and dc offset have a devastating effect on digital predistortion for power amplifier linearization circuits. We construct compensation circuit to remove these errors, and conduct an experiment. The imbalance errors are compensated by using the output spectrum of modulator. The image spurious (-56.74 dBm) with gain, phase and the dc offset spurious (-43 83 dBm) are reduced to -93.21 dBm and -93.56 dBm, respectively. These experimental results illustrate that modulationerrors can be eliminated.

著者

KIM ByungKyun CHOI HyungJin

出版者

一般社団法人電子情報通信学会

雑誌

IEICE transactions on communications (ISSN:09168516)

巻号頁・発行日

vol.81, no.3, pp.647-658, 1998-03-25

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In this paper, we propose a teletraffic model and evaluate the performance in the terrestrial/satellite integrated mobile communication networks having hierarchical structure consisting of terrestrial microcell and satellite spot beam. In the proposed teletraffic model, both the subscriber terminal mobility in the terrestrial microcell and the satellite mobility in the LEO satellite spot beam are considered. The overflow traffic from microcell can be accommodated by the satellite spot beam and is analyzed by IPP(Interrupted Poisson Process) which is often used to analyze non-random overflow traffic. Various reservation channels for handoff calls in terrestrial microcell and satellite spot beam are considered. New calls initially directed to the satellite spot beam are also considered for reservation channels. Carried traffic, blocking, forced termination and non-completion probabilities are evaluated for the overall integrated networks.

著者

ICHIKAWA Haruhisa SHIMIZU Masashi AKABANE Kazunori

出版者

一般社団法人電子情報通信学会

雑誌

IEICE transactions on communications (ISSN:09168516)

巻号頁・発行日

vol.90, no.12, pp.3445-3451, 2007-12-01

被引用文献数

8

---

Many devices are expected to be networked with wireless appliances such as radio frequency identification (RFID) tags and wireless sensors, and the number of such appliances will greatly exceed the number of PCs and mobile telephones. This may lead to an essential change in the network architecture. This paper proposes a new network architecture called the appliance defined ubiquitous network (ADUN), in which wireless appliances will be networked without network protocol standards. Radio space information rather than individual appliance signals is carried over the ADUN in the form of a stream with strong privacy/security control. It should be noted that this is different from the architectural principles of the Internet. We discuss a network-appliance interface that is sustainable over a long period, and show that the ADUN overhead will be within the scope of the broadband network in the near future.

著者

Kazunori AKABANE Nobuaki MOCHIZUKI Shigeru TERUHI Mamoru KOBAYASHI Shuichi YOSHINO Masashi SHIMIZU Kazuhiro UEHARA

出版者

一般社団法人 電子情報通信学会

雑誌

IEICE Transactions on Communications (ISSN:09168516)

巻号頁・発行日

vol.E99.B, no.9, pp.1920-1929, 2016-09-01 (Released:2016-09-01)

参考文献数

27

被引用文献数

4

---

In the near future, many sensors and terminals will be connected to the public network to provide various convenient IoT/M2M services. In order to connect many sensors to the network efficiently, wireless communication systems in the 920MHz band are seen as attractive solutions. We are focusing on the 920MHz band to research and develop high-capacity protocols that can accommodate many terminals, and low power consumption technologies for battery-driven terminals. In this paper, we describe the following three concrete wireless systems that use our proposals. (1) A physical distribution pallet management system that can handle thousands of pallet-embedded sensors and a wireless module with a battery lifetime of about ten years. (2) Water leakage monitoring system for underground pipes by using sensors and a wireless module in each valve box. (3) A wide-area and high-capacity radio relay system for smart metering services like the reading of gas meters. The radio relay system can accommodate various sensors and terminals and has large potential for providing various IoT/M2M services in conjunction with smart metering services.

著者

CHEN Zhijia LIN Chuang CHEN Yang NIVARGI Vaibhav CAO Pei

出版者

The Institute of Electronics, Information and Communication Engineers

雑誌

IEICE transactions on communications (ISSN:09168516)

巻号頁・発行日

vol.91, no.12, pp.3842-3850, 2008-12-01

被引用文献数

1 5

---

With the popularity of BitTorrent-like P2P applications, improving its performance has been an active research area. Super-seeding, a special upload policy for the initial seeder, improves the efficiency in producing multiple seeds and reduces the uploading bytes of content initiators, thus being highly expected as a promising solution for improving downloading performance while decreasing uploading cost. However, the overall impacts of super seeding upon BitTorrent performance remain a question and have not been analyzed so far in literature. In this paper, we present an analytical and experimental study over the performance of super-seeding scheme. We attempt to answer the following questions: whether and how much super-seeding saves uploading cost, whether the overall downloading time is decreased by super-seeding, and in which circumstances super-seeding performs worse. Based on the seeding process, our analytical study gives formulas on the new piece distribution time, average downloading time and minimum distribution time for heterogeneous P2P file distribution system with super-seeding. Robust evidence supporting the use (or not) of super-seeding is given based on our worldwide Internet experiments over wide distribution of 250 PlanetLab nodes. With a well-designed experimental scenario, we study the overall download time and upload cost of super seeding scheme under varying seed bandwidth and peer behavior. Results show that super-seeding can save an upload ratio of 20% and does help speeding up swarms in certain modes. Tentative conclusions about the effectiveness of super-seeding and its optimal working circumstances are given with inside mechanism analyzed and negative factor identified. Our work not only provides reference for the potential adoption of super-seeding in BitTorrent and other P2P applications, but also much insights for the tussle of enhancing of Quality of Experience (QoE) and saving cost for a large-scale BitTorrent-like P2P commercial application.

著者

Katsuyuki HANEDA

出版者

The Institute of Electronics, Information and Communication Engineers

雑誌

IEICE TRANSACTIONS on Communications (ISSN:09168516)

巻号頁・発行日

vol.E98-B, no.5, pp.755-772, 2015-05-01

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Millimeter-wave (mm-wave) radio is attracting attention as one of the key enabling physical layer technologies for the fifth-generation (5G) mobile access and backhaul. This paper aims at clarifying possible roles of mm-wave radio in the 5G development and performing a comprehensive literature survey on mm-wave radio channel modeling essential for the feasibility study. Emphasis in the literature survey is laid on grasping the typical behavior of mm-wave channels, identifying missing features in the presently available channel models for the design and evaluation of the mm-wave radio links within the 5G context, and exemplifying different channel modeling activities through analyses performed in the authors' group. As a key technological element of the mm-wave radios, reduced complexity beamforming is also addressed. Design criteria of the beamforming are developed based on the spatial multipath characteristics of measured indoor mm-wave channels.

著者

Takaaki DEGUCHI Yoshiaki TANIGUCHI Go HASEGAWA Yutaka NAKAMURA Norimichi UKITA Kazuhiro MATSUDA Morito MATSUOKA

出版者

一般社団法人 電子情報通信学会

雑誌

IEICE Transactions on Communications (ISSN:09168516)

巻号頁・発行日

vol.E99.B, no.2, pp.347-355, 2016-02-01 (Released:2016-02-01)

参考文献数

17

被引用文献数

1 1

---

In this paper, we propose a workload assignment policy for reducing power consumption by air conditioners in data centers. In the proposed policy, to reduce the air conditioner power consumption by raising the temperature set points of the air conditioners, the temperatures of all server back-planes are equalized by moving workload from the servers with the highest temperatures to the servers with the lowest temperatures. To evaluate the proposed policy, we use a computational fluid dynamics simulator for obtaining airflow and air temperature in data centers, and an air conditioner model based on experimental results from actual data center. Through evaluation, we show that the air conditioners' power consumption is reduced by 10.4% in a conventional data center. In addition, in a tandem data center proposed in our research group, the air conditioners' power consumption is reduced by 53%, and the total power consumption of the whole data center is exhibited to be reduced by 23% by reusing the exhaust heat from the servers.