Monday, January 27, 2020
Design of Spatial Decoupling Scheme
Design of Spatial Decoupling Scheme Design of Spatial Decoupling Scheme using Singular Value Decomposition for Multi-User Systems Abstract In this paper, we present the use of a polynomial singular value decomposition (PSVD) algorithm to examine a spatial decoupling based block transmission design for multiuser systems. This algorithm facilitates joint and optimal decomposition of matrices arising inherently in multiuser systems. Spatial decoupling allows complex multichannel problems of suitable dimensionality to be spectrally diagonalized by computing a reduced-order memoryless matrix through the use of the coordinated transmit precoding and receiver equalization matrices. A primary application of spatial decoupling based system can be useful in discrete multitone (DMT) systems to combat the induced crosstalk interference, as well as in OFDM with intersymbol interference. We present here simulation-based performance analysis results to justify the use of PSVD for the proposed algorithm. Index Terms-polynomial singular value decomposition, paraunitary systems, MIMO system. INTRODUCTION Block transmission based systems allows parallel, ideally noninterfering, virtual communication channels between multiuser channels. Minimally spatial decoupling channels are needed whenever more than two transmitting channels are communicate simultaneously. The channel of our interest here, is the multiple input multiple output channels, consisting of multiple MIMO capable source terminals and multiple capable destinations. This scenario arises, obviously, in multi-user channels. Since certain phases of relaying involves broadcasting, it also appears in MIMO relaying contexts. The phrase MIMO broadcast channel is frequently used in a loose sense in the literature, to include point-to-multipoint unicast (i.e. private) channels carrying different messages from a single source to each of the multiple destinations (e.g. in multi-user MIMO). Its use in this paper is more specific, and denotes the presence of at least one common virtual broadcast channel from the source to the destinations. The use of iterative and non-iterative spatial decoupling techniques in multiuser systems to achieve independent channels has been investigated, for instance in [1]-[9]. Their use for MIMO broadcasting, which requires common multipoint-to-multipoint MIMO channels is not much attractive, given the fact that the total number of private and common channels is limited by the number of antennas the source has. Wherever each receiver of a broadcast channel conveys what it receives orthogonally to the same destination, as in the case of pre-and post-processing block transmission, the whole system can be envisaged as a single point-to-point MIMO channel. Block transmission techniques have been demonstrated for point-to-point MIMO channels to benefit the system complexities. Other advantages includes: (i) channel interference is removed by creating $K$ independent subchannels; (ii) paraunitarity of precoder allows to control transmit power; (iii) paraunitarity of equalizer does not amplify the channel noise; (iv) spatial redundancy can be achieved by discarding the weakest subchannels. Though the technique outperform the conventional signal coding but had its own demerits. Amongst many, it shown in cite{Ta2005,Ta2007} that an appropriate additional amount of additive samples still require individual processing, e.g. per- tone equalisation, to remove ISI, and the receiver does not exploit the case of structured noise. However, the choice of optimal relay gains, although known for certain cases (e.g. [10], [11]), is not straightforward with this approach. Since the individual equalization have no non-iterative means of decoding the signals, this approach cannot be used with decode-and-forward (DF), and code-and-forward (CF) relay processing schemes. The use of zero-forcing at the destination has been examined [12], [13] as a mean of coordinated beamforming, since it does not require transmitter processing. The scheme scales to any number of destinations, but requires each destination to have no less antennas than the source. Although not used as commonly as the singular value decomposition (SVD), generalized singular value decomposition (GSVD) [14, Thm. 8.7.4] is not unheard of in the wireless literature. It has been used in multi-user MIMO transmission [15], [16], MIMO secrecy communication [17], [18], and MIMO relaying [19]. Reference [19] uses GSVD in dual-hop AF relaying with arbitrary number of relays. Since it employs zero-forcing at the relay for the forward channel, its use of GSVD appears almost similar to the use of SVD in [1]. Despite GSVD being the natural generalization of SVD for two matrices, we are yet to see in the literature, a generalization of SVD-based beamforming to GSVD-based beamforming. Although the purpose and the use is somewhat different, the reference [17, p.1] appears to be the first to hint the possible use of GSVD for beamforming. In present work, we illustrate how GSVD can be used for coordinated beamforming in source-to-2 destination MIMO broadcasting; thus in AF, DF and CF MIMO relaying. We also present comparative, simulation-based performance analysis results to justify GSVD-based beamforming. The paper is organized as follows: Section II presents the mathematical framework, highlighting how and under which constraints GSVD can be used for beamforming. Section III examines how GSVD-based beamforming can be applied in certain simple MIMO and MIMO relaying configurations. Performance analysis is conducted in section IV on one of these applications. Section V concludes with some final remarks. Notations: Given a matrix A and a vector v, (i) A(i, j) gives the ith element on the jth column of A; (ii) v(i) {ˆy1 }R(r+1,r+s) = ˜Π£{x }R(r+1,r+s) + _ UHn1 _ R(r+1,r+s) , {ˆy2 }R(pà ¢Ã‹â€ ’t+r+1,pà ¢Ã‹â€ ’t+r+s) = ˜Άº{x }R(r+1,r+s) + _ VHn2 _ R(pà ¢Ã‹â€ ’t+r+1,pà ¢Ã‹â€ ’t+r+s) , {ˆy1 }R(1,r) = {x }R(1,r) + _ UHn1 _ R(1,r) , {ˆy2 }R(pà ¢Ã‹â€ ’t+r+s+1,p) = {x }R(r+s+1,t) + _ VHn2 _ R(pà ¢Ã‹â€ ’t+r+s+1,p) . (1) gives the element of v at the ith position. {A}R(n) and {A}C(n) denote the sub-matrices consisting respectively of the first n rows, and the first n columns of A. Let {A}R(m,n) denote the sub-matrix consisting of the rows m through n of A. The expression A = diag (a1, . . . , an) indicates that A is rectangular diagonal; and that first n elements on its main diagonal are a1, . . . , an. rank (A) gives the rank of A. The operators ( à £Ã†â€™Ã‚ » )H, and ( à £Ã†â€™Ã‚ »)à ¢Ã‹â€ ’1 denote respectively the conjugate transpose and the matrix inversion. C mÃÆ'-n is the space spanned by mÃÆ'-n matrices containing possibly complex elements. The channel between the wireless terminals T1 and T2 in a MIMO system is designated T1 à ¢Ã¢â‚¬ ’T2. II. MATHEMATICAL FRAMEWORK Let us examine GSVD to see how it can be used for beamforming. There are two major variants of GSVD in the literature (e.g. [20] vs. [21]). We use them both here to elaborate the notion of GSVD-based beamforming. A. GSVD Van Loan definition Let us first look at GSVD as initially proposed by Van Loan [20, Thm. 2]. Definition 1: Consider two matrices, H à ¢Ã‹â€ ˆC mÃÆ'-n with m à ¢Ã¢â‚¬ °Ã‚ ¥n, and G à ¢Ã‹â€ ˆC pÃÆ'-n, having the same number n of columns. Let q = min (p, n). H and G can be jointly decomposed as H = UÃŽÂ £Q, G = VΆºQ (2) where (i) U à ¢Ã‹â€ ˆC mÃÆ'-m,V à ¢Ã‹â€ ˆC pÃÆ'-p are unitary, (ii) Q à ¢Ã‹â€ ˆC nÃÆ'-n non-singular, and (iii) ÃŽÂ £= diag (à ƒ1, . . . , à ƒn) à ¢Ã‹â€ ˆC mÃÆ'-n, à ƒi à ¢Ã¢â‚¬ °Ã‚ ¥0; Άº= diag (ÃŽÂ »1, . . . , ÃŽÂ »q) à ¢Ã‹â€ ˆC pÃÆ'-n, ÃŽÂ »i à ¢Ã¢â‚¬ °Ã‚ ¥0. As a crude example, suppose that G and H above represent channel matrices of MIMO subsystems S à ¢Ã¢â‚¬ ’D1 and S à ¢Ã¢â‚¬ ’D2 having a common source S. Assume perfect channel-stateinformation (CSI) on G and H at all S,D1, and D2. With a transmit precoding matrix Qà ¢Ã‹â€ ’1, and receiver reconstruction matrices UH,VH we get q non-interfering virtual broadcast channels. The invertible factor Q in (2) facilitates jointprecoding for the MIMO subsystems; while the factors U,V allow receiver reconstruction without noise enhancement. Diagonal elements 1 through q of ÃŽÂ £,Άºrepresent the gains of these virtual channels. Since Q is non-unitary, precoding would cause the instantaneous transmit power to fluctuate. This is a drawback not present in SVD-based beamforming. Transmit signal should be normalized to maintain the average total transmit power at the desired level. This is the essence of GSVD-based beamforming for a single source and two destinations. As would be shown in Section III, this three-terminal configuration appears in various MIMO subsystems making GSVD-based beamforming applicable. B. GSVD Paige and Saunders definition Before moving on to applications, let us appreciate GSVDbased beamforming in a more general sense, through another form of GSVD proposed by Paige and Saunders [21, (3.1)]. This version of GSVD relaxes the constraint m à ¢Ã¢â‚¬ °Ã‚ ¥n present in (2). Definition 2: Consider two matrices, H à ¢Ã‹â€ ˆC mÃÆ'-n and G à ¢Ã‹â€ ˆC pÃÆ'-n, having the same number n of columns. Let CH = _ HH,GH _ à ¢Ã‹â€ ˆC nÃÆ'-(m+p), t = rank(C), r = t à ¢Ã‹â€ ’rank (G) and s = rank(H) + rank (G) à ¢Ã‹â€ ’t. H and G can be jointly decomposed as H = U (ÃŽÂ £ 01 )Q = UÃŽÂ £{Q}R(t) , G = V (Άº 02 )Q = VΆº{Q}R(t) , (3) where (i) U à ¢Ã‹â€ ˆC mÃÆ'-m,V à ¢Ã‹â€ ˆC pÃÆ'-p are unitary, (ii) Q à ¢Ã‹â€ ˆC nÃÆ'-n non-singular, (iii) 01 à ¢Ã‹â€ ˆC mÃÆ'-(nà ¢Ã‹â€ ’t), 02 à ¢Ã‹â€ ˆC pÃÆ'-(nà ¢Ã‹â€ ’t) zero matrices, and (iv) ÃŽÂ £Ãƒ ¢Ã‹â€ ˆC mÃÆ'-t,ΆºÃƒ ¢Ã‹â€ ˆC pÃÆ'-t have structures ÃŽÂ £_ à ¢Ã… ½Ã¢â‚¬ º à ¢Ã… ½Ã‚ IH ˜Π£ 0H à ¢Ã… ½Ã… ¾ à ¢Ã… ½Ã‚ and Άº_ à ¢Ã… ½Ã¢â‚¬ º à ¢Ã… ½Ã‚ 0G ˜Άº IG à ¢Ã… ½Ã… ¾ à ¢Ã… ½Ã‚ . IH à ¢Ã‹â€ ˆC rÃÆ'-r and IG à ¢Ã‹â€ ˆC (tà ¢Ã‹â€ ’rà ¢Ã‹â€ ’s)ÃÆ'-(tà ¢Ã‹â€ ’rà ¢Ã‹â€ ’s) are identity matrices. 0H à ¢Ã‹â€ ˆC (mà ¢Ã‹â€ ’rà ¢Ã‹â€ ’s)ÃÆ'-(tà ¢Ã‹â€ ’rà ¢Ã‹â€ ’s), and 0G à ¢Ã‹â€ ˆC (pà ¢Ã‹â€ ’t+r)ÃÆ'-r are zero matrices possibly having no rows or no columns. ˜Π£= diag (à ƒ1, . . . , à ƒs) ,˜Άº= diag (ÃŽÂ »1, . . . , ÃŽÂ »s) à ¢Ã‹â€ ˆC sÃÆ'-s such that 1 > à ƒ1 à ¢Ã¢â‚¬ °Ã‚ ¥. . . à ¢Ã¢â‚¬ °Ã‚ ¥ à ƒs > 0, and à ƒ2 i + ÃŽÂ »2i = 1 for i à ¢Ã‹â€ ˆ{1, . . . , s}. Let us examine (3) in the MIMO context. It is not difficult to see that a common transmit precoding matrix _ Qà ¢Ã‹â€ ’1 _ C(t) and receiver reconstruction matrices UH,VH would jointly diagonalize the channels represented by H and G. For broadcasting, only the columns (r+1) through (r +s) of ÃŽÂ £and Άºare of interest. Nevertheless, other (t à ¢Ã‹â€ ’s) columns, when they are present, may be used by the source S to privately communicate with the destinations D1 and configuration # common channels # private channels S à ¢Ã¢â‚¬ ’ {D1,D2} S à ¢Ã¢â‚¬ ’D1 S à ¢Ã¢â‚¬ ’D2 m > n,p à ¢Ã¢â‚¬ °Ã‚ ¤n p n à ¢Ã‹â€ ’p 0 m à ¢Ã¢â‚¬ °Ã‚ ¤n, p > n m 0 n à ¢Ã‹â€ ’m m à ¢Ã¢â‚¬ °Ã‚ ¥n, p à ¢Ã¢â‚¬ °Ã‚ ¥n n 0 0 m + p à ¢Ã‹â€ ’n n à ¢Ã‹â€ ’p n à ¢Ã‹â€ ’m (m + p) > n n à ¢Ã¢â‚¬ °Ã‚ ¥(m + p) 0 m p TABLE I NUMBERS OF COMMON CHANNELS AND PRIVATE CHANNELS FOR DIFFERENT CONFIGURATIONS D2. It is worthwhile to compare this fact with [22], and appreciate the similarity and the conflicting objectives GSVDbased beamforming for broadcasting has with MIMO secrecy communication. Thus we can get ˆy1 à ¢Ã‹â€ ˆC mÃÆ'-1, ˆy2 à ¢Ã‹â€ ˆC pÃÆ'-1 as in (1) at the detector input, when x à ¢Ã‹â€ ˆC tÃÆ'-1 is the symbol vector transmitted. It can also be observed from (1) that the private channels always have unit gains; while the gains of common channels are smaller. Since, à ƒis are in descending order, while the ÃŽÂ »is ascend with i, selecting a subset of the available s broadcast channels (say k à ¢Ã¢â‚¬ °Ã‚ ¤s channels) is somewhat challenging. This highlights the need to further our intuition on GSVD. C. GSVD-based beamforming Any two MIMO subsystems having a common source and channel matrices H and G can be effectively reduced, depending on their ranks, to a set of common (broadcast) and private (unicast) virtual channels. The requirement for having common channels is rank (H) + rank (G) > rank (C) where C = _ HH,GH _ H. When the matrices have full rank, which is the case with most MIMO channels (key-hole channels being an exception), this requirement boils down to having m +p > n . Table I indicates how the numbers of common channels and private channels vary in full-rank MIMO channels. It can be noted that the cases (m > n,p à ¢Ã¢â‚¬ °Ã‚ ¤n) and (m à ¢Ã¢â‚¬ °Ã‚ ¥n, p à ¢Ã¢â‚¬ °Ã‚ ¥n) correspond to the form of GSVD discussed in the Subsection II-A. Further, the case n à ¢Ã¢â‚¬ °Ã‚ ¥(m + p) which produces only private channels with unit gains, can be seen identical to zero forcing at the transmitter. Thus, GSVD-based beamforming is also a generalization of zero-forcing. Based on Table I, it can be concluded that the full-rank min (n,m + p) of the combined channel always gets split between the common and private channels. D. MATLAB implementation A general discussion on the computation of GSVD is found in [23]. Let us focus here on what it needs for simulation: namely its implementation in the MATLAB computational environment, which extends [14, Thm. 8.7.4] and appears as less restrictive as [21]. The command [V, U, X, Lambda, Sigma] = gsvd(G, H); gives1 a decomposition similar to (3). Its main deviations from (3) are, 1Reverse order of arguments in and out of gsvd function should be noted. ) ) D1 y1 , r1 S x ,w ( ( ) ) D2 y2 , r2 _ H1 __ n1 _ __ H2 n2 Fig. 1. Source-to-2 destination MIMO broadcast system à ¢Ã¢â€š ¬Ã‚ ¢ QH = X à ¢Ã‹â€ ˆC nÃÆ'-t is not square when t . Precoding for such cases would require the use of the pseudo-inverse operator. à ¢Ã¢â€š ¬Ã‚ ¢ ÃŽÂ £has the same block structure as in (3). But the structure of Άºhas the block 0G shifted to its bottom as follows: Άº_ à ¢Ã… ½Ã¢â‚¬ º à ¢Ã… ½Ã‚ ˜Άº IG 0G à ¢Ã… ½Ã… ¾ à ¢Ã… ½Ã‚ . This can be remedied by appropriately interchanging the rows of Άºand the columns of V. However, restructuring Î†ºis not a necessity, since the column position of the block ˜Άºwithin Άºis what matters in joint precoding. Following MATLAB code snippet for example jointly diagonalizes H,G to obtain the s common channels (3) would have given. MATLAB code % channel matrices H = (randn(m,n)+i*randn(m,n))/sqrt(2); G = (randn(p,n)+i*randn(p,n))/sqrt(2); % D1, D2: diagonalized channels [V,U,X,Lambda,Sigma] = gsvd(G,H); w = X*inv(X*X); C = [H G]; t = rank(C); r = t rank(G); s = rank(H)+rank(G)-t; D1 = U(:,r+1:r+s)*H*w(:,r+1:r+s); D2 = V(:,1:s)*G*w(:,r+1:r+s); III. APPLICATIONS Let us look at some of the possible applications of GSVDbased beamforming. We assume the Van Loan form of GSVD for simplicity, having taken for granted that the dimensions are such that the constraints hold true. Nevertheless, the Paige and Saunders form should be usable as well. A. Source-to-2 destination MIMO broadcast system Consider the MIMO broadcast system shown in Fig. 1, where the source S broadcasts to destinations D1 and D2. MIMO subsystems S à ¢Ã¢â‚¬ ’D1 and S à ¢Ã¢â‚¬ ’D2 are modeled to have channel matrices H1 ,H2 and additive complex Gaussian noise vectors n1 , n2. Let x = [x1, . . . , xn]T ) ) R1 y1 , F1 ( ( S x ,w ( ( ) ) D y3 ,r1 y4 ,r2 ) ) R2 y2 , F2 ( ( _ ___ H3 _ n3 H1 ___ n1 _ ___ H2 n2 _ H4 ___ n4 Fig. 2. MIMO relay system with two 2-hop-branches be the signal vector desired to be transmitted over n à ¢Ã¢â‚¬ °Ã‚ ¤Ã‚ min (rank (H1 ) , rank (H2 )) virtual-channels. The source employs a precoding matrix w. The input y1 , y2 and output ˆy1 , ˆy2 at the receiver filters r1 , r2 at D1 and D2 are given by y1 = H1wx + n1 ; ˆy1 = r1 y1 , y2 = H2wx + n2 ; ˆy2 = r2 y2 . Applying GSVD we get H1 = U1 ÃŽÂ £1 V and H2 = U2 ÃŽÂ £2V. Choose the precoding matrix w = ÃŽÂ ± _ Và ¢Ã‹â€ ’1 _ C(n) ; and receiver reconstruction matrices r1 = _ U1 H _ R(n) _ , r2 = U2 H _ R(n) . The constant ÃŽÂ ± normalizes the total average transmit power. Then we get, ˆy1(i) = ÃŽÂ ±ÃƒÅ½Ã‚ £1(i, i) x(i) + Ëœn1(i) , ˆy2(i) = ÃŽÂ ±ÃƒÅ½Ã‚ £2(i, i) x(i) + Ëœn2(i), ià ¢Ã‹â€ ˆ{1 . . . n}, where Ëœn1 , Ëœn2 have the same noise distributions as n1 , n2 . B. MIMO relay system with two 2-hop-branches (3 time-slots) Fig. 2 shows a simple MIMO AF relay system where a source S communicates a symbol vector x with a destination D via two relays R1 and R2. MIMO channels S à ¢Ã¢â‚¬ ’R1, S à ¢Ã¢â‚¬ ’ R2, R1 à ¢Ã¢â‚¬ ’D and R2 à ¢Ã¢â‚¬ ’D are denoted: Hi , i à ¢Ã‹â€ ˆ{1, 2, 3, 4}. Corresponding channel outputs and additive complex Gaussian noise vectors are yi , ni for i à ¢Ã‹â€ ˆ{1, 2, 3, 4}. Assume relay operations to be linear, and modeled as matrices F1 and F2 . Assume orthogonal time-slots for transmission. The source S uses w as the precoding matrix. Destination D uses different reconstruction matrices r1 , r2 during the time slots 2 and 3. Then we have: Time slot 1: y1 = H1wx + n1 , y2 = H2wx + n2 Time slot 2: y3 = H3 F1 y1 + n3 Time slot 3: y4 = H4 F2 y2 + n4 Let ˆy = r1 y3 +r2 y4 be the input to the detector. Suppose n à ¢Ã¢â‚¬ °Ã‚ ¤min i (rank (Hi )) virtual-channels are in use. ) ) R y1 , F ( ( S x ,w ( ( ) ) D y2 ,r1 y3 ,r2 _ ___ H3 _ n3 H1 ___ n1 H2 _ n2 Fig. 3. MIMO relay system having a direct path and a relayed path Applying GSVD on the broadcast channel matrices we get H1 = U1 ÃŽÂ £1 Q and H2 = U2 ÃŽÂ £2 Q. Through SVD we obtain H3 = V1 Άº1 R1 H and H4 = V2 Άº2 R2 H. Choose w = ÃŽÂ ± _ Qà ¢Ã‹â€ ’1 _ C(n) ; F1 = R1U1 H; F2 = R2U2 H; r1 = _ V1 H _ R(n) ; r2 = _ V2 H _ R(n) . The constant ÃŽÂ ± normalizes the total average transmit power. Then we get
Sunday, January 19, 2020
The visit summary
The story opens with the town of Guellen (which literally means â€Å"excrement†) preparing for the arrival of famed millionairess Claire Zachanassian. The town is In a state of disrepair, and the residents are suffering considerable hardship and poverty. They hope that Claire, a native of the small town, will provide them with much- needed funds. Alfred Ill, the owner of Guellen's general store and the most popular man In town, was Claire's lover when they were young, and agrees with the Mayor that the task of convincing her to make a donation should fall to him.As the town athers at the railway station to prepare for Claire's arrival, they are met with an unexpected surprise when Claire steps off of an earlier train. She Is grand, grotesque, and fantastic, and Is accompanied by two henchmen, her husband, a butler, and two eunuchs, along with a coffin, a caged black panther, and various pieces of luggage. She begins a flirtatious exchange with Ill, and they promptly revlslt t heir old haunts: Petersen's Barn and Konrad's Village Wood. Ill finds her as delightful as ever, though they are both now in their sixties and significantly overweight.Claire draws Ill's attention to her prosthetic leg and artificial hand. After settling into the Golden Apostle Hotel, Claire joins the rest of the town, who have gathered outside for a homecoming celebration. A band plays, gymnasts perform, and the Mayor gives a speech. Claire takes the opportunity to announce that she will make a donation of one million dollars, half for the town and half to be shared among the families. The townspeople are overjoyed, but their happiness is dampened when Claire's Butler steps forward to reveal her condition. The Butler was once the Lord Chief Justice ofGuellen, and had overseen the paternity suit that Claire had brought against Ill in 1910. In the suit, Ill had produced two false witnesses (who have since been transformed into Claire's eunuchs), and the court had ruled in his favor. Ill went on to marry Matilda, who owned the general store, and Claire moved to Hamburg and became a prostitute. She declares to the townspeople that she has come to Guellen to prove that Justice can, indeed, be bought. Her donation is conditional on Ill's death. When the Mayor refuses, the town cheers in support, but Claire states rather minously, â€Å"I'll wait. Ill feels generally confident about his status in the town. However, as time passes, he begins to feel troubled about their growing discontent, and then increasingly fearful as he begins to notice the proliferation of new yellow shoes on the feet of the townsmen, and the fact that everyone seems to be purchasing especially expensive items on credit. He goes to see the Policeman to demand that he arrest Claire for having threatened his life, but the Policeman tells him that the threat is nonsense. Ill then turns to the Mayor, who echoes similar sentiments.Both figures are armed, because Claire's black panther has escaped f rom his cage and is prowling about the town. This only feeds Ill's fear, since â€Å"my black panther†was Claire's pet name for him In their youth. He runs to see the Priest, but the Priest seems to be turning away from him as well, as he effectively Ignores Ill's fears and Instead draws attention to the magnificent new church bell. Slowly, the standard of living in the town rises, even though the townspeople continue to assure Ill that he is safe. Claire then receives the news that her black panther has beenKlllea, ana sne nas a Tuneral song played In Its memory. In an effort to escape, Ill heads to the railway station, but finds that, strangely, the entire town is gathered there. They ask him where he is going, and he says that he is planning to move to Australia. They wish him well, again assuring him that he has nothing to fear in Guellen, but Ill grows increasingly nervous nonetheless. The train arrives, but he decides not to board, believing that someone will stop him anyway. Paralyzed, he collapses in the crowd, crying, â€Å"I'm lost! After some time passes and Claire weds a ew husband in the Guellen Cathedral, the Doctor and the Schoolmaster go to see her and explain that the townspeople have run up considerable debts since her arrival. The Schoolmaster appeals to her sense of humanity and begs her to abandon her desire for vengeance and help the town out of the goodness of her heart. She reveals to them that she already actually owns all of properties in the town, and that she is the reason the businesses have been shut down and caused stagnation and poverty for the citizens.The Doctor and the Schoolmaster are aghast at this revelation. In the meantime, Ill has been pacing the room above the general store, his terror growing as the townspeople buy more and more expensive products on credit. News reporters, having received word of Claire's imminent wedding, are everywhere, and they enter the store to get the scoop on Ill, having heard that he was Claire's lover back in the day. The Schoolmaster, drunk, tries to inform the press about Claire's cruel proposal, but the townspeople stop him. Finally Ill descends the stairs, surprised at the hubbub, but quiet.The reporters clear the room when they hear hat Claire has Just divorced the man she has Just married, and has found a new lover. After the confusion has cleared, the Schoolmaster and Ill have an honest discussion. The Schoolmaster explains that he is certain that Ill will be killed, and admits that he will ultimately Join the ranks of the murderers. Ill calmly states that he has accepted his guilt, and acknowledges that the town's suffering is his fault. The Schoolmaster leaves, and Ill is confronted by the Mayor, who asks whether Ill will accept the town's Judgment at that evening's meeting. Ill says that he will.The Mayor hen suggests that Ill make things easier on everyone and shoot himself, but Ill refuses, insisting that the town must go through the process of act ually Judging and then killing him. Ill goes for a ride in his son's newly-purchased car, accompanied by his wife, Matilda, and his daughter, both of whom are wearing new outfits. As they drive through Konrad's Village Wood, Ill says that he is going to go for a walk through the woods before heading to the town meeting. His family continues on to the movie theater. In the woods, Ill comes across Claire, who is walking with her newest husband.She asks her husband to leave so that she and Ill can speak privately. They reminisce about the past, and make plans for the future. Claire tells Ill that she plans to take his body away in the coffin to a mausoleum in Capri that overlooks the Mediterranean. She also tells Ill that she has never stopped loving him, but that over time her love has grown into something monstrous. The town meeting is flooded with press, and the town publicly announces their acceptance of Claire's donation. They then go through the formality of a vote, which is unan imous, and the Mayor states that they have Ill to thank for their new-found wealth.The press is then ushered out of the auditorium to enjoy refreshments. The doors are locked, and the lights are dimmed. The Priest crosses Ill, and he is killed by the townsmen. Just as a reporter reappears In tne au01torlum, tne Doctor announces tnat II I nas oleo Trom a neart attack. The reporters gather, and declare that Ill has died from Joy. Claire examines the corpse, gives the Mayor his check, and leaves the town with Ill's body in the coffin that she brought with her when she arrived in Guellen. Claire boards the train at the railway station, and the visit comes to an end.
Saturday, January 11, 2020
Leadership Ethics Essay
When the decision is made to become a nurse, there is a code of ethics in place that they agree to abide by (ANA, 2001). The Registered Nurse who demonstrates leadership and ethics places their own personal and religious beliefs aside to do what is truly best for the outcomes of those they serve. As a school nurse, the obligation to keep the students safe and healthy should and often does come first and foremost. Counseling abstinence, though necessary, will not stop teens from having sexual intercourse and it will not teach them to protect themselves from sexually transmitted diseases and unplanned pregnancies. Those entrusted with the health and welfare of our young people must teach them how to utilize condoms to protect themselves against unwanted pregnancies and contacting sexually transmitted diseases, (STDs). It is well known that Catholics do not use birth control in any way shape or form; this includes the use of condoms. STD’s and unplanned pregnancies are viewed as consequences to one’s sins. When the school nurse is also a devout Catholic, issues surrounding teens, sex, and birth control can cause moral distress and make the nurse question the actions they have taken. It was learned in week 4 that â€Å"Actions are only ethical if motivated by a duty to do the right thing†(CCN, 2013). What IS the right thing to do? Teens, Sexually Transmitted Diseases, & Abstinence There are nineteen million new cases of bacterial and viral cases of sexually transmitted diseases diagnosed in the United States each year and 50% of these cases are diagnosed in adolescent males and females and most case studies focus on abstinence or on the use of condoms (Akers, Gold, Coyne-Beasley, & Corbie-Smith, 2012). â€Å"It is estimated that by the end of high school, nearly two thirds of American youth are sexually active, and one in five has had four or more sexual partners†(Starkman & Rajani, 2002 p. 313). Sex education should include the worth and benefits of abstinence but there is little evidence that abstinence only programs work. Teens who participate in these programs may not refrain from sexual intercourse longer or become sexually active sooner than those who participate in programs that promote the use of condoms. There is no evidence that those who do participate in abstinence only programs are less sexually active but there is evidence that those w ho do participate in all-inclusive program practice safer sex when they do become sexually active (Starkman & Rajani, 2002). Catholicism & the Use of Condoms Cardinal Jaime Sin issued a pastoral exhortation in 2001 stating that â€Å"the condom corrupts and weakens people, destroys families and individuals, and also spreads promiscuity†(Arie, 2005 p. 926). The Catholic church’s negative stance on condoms in that they murder sperm and promote immoral behavior in spite of the fact that Catholic organizations care for 25% of all those that are afflicted with HIV/AIDS (Arie, 2005), causes great moral distress for Catholic nurses who have an obligation to practice using the Code of Ethics outlined by the ANA. Non-Catholic teenagers are more likely to use and know about condom usage than Catholic teens (Kinsman, Nakiyingi, Kamali, & Whitworth, 2001) even with those who are higher up in the Catholic organization voicing opinions and recognizing that there is power in condoms saving lives, and the Catholic church refuses to endorse their use and educate their members (Arie,2005). Conclusion There is over whelming evidence that the use of condoms is beneficial in preventing the transmission of STD’s among adolescents. With over half of all sexually transmitted diseases being reported among young people, it is of upmost importance that those working with teenagers, where it concerns sexuality, be prepared to teach them about the importance of protecting themselves from STD’s by promoting the use of condoms as counseling abstinence will not stop teens from having sexual intercourse. The Catholic Church refuses to promote the use of condoms. Therefore, it is even more important, when looking at the imperial evidence and outcomes from statistics when condoms are used as a preventative measure for STD’s, for the Catholic nurse to put aside her own religious and moral beliefs in favor of teaching the significance of using condoms for the prevention of sexually transmitted diseases and unplanned pregnancies. Furthermore, it is of this author’s opi nion that no nurse who has protected a young person by preventing pregnancy or an STD, through comprehensive sex education and counseling that teenager to use condoms, should ever feel any moral distress or be persecuted by her congregation for doing the right thing. References American Nurses Association. (2001). Code of ethics for nurses with interpretive statements. New York: Author. Akers, A. Y., Gold, M. A., Coyne-Beasley, T., & Corbie-Smith, G. (2012). A Qualitative Study of Rural Black Adolescents’ Perspectives on Primary STD Prevention Strategies. Perspectives On Sexual & Reproductive Health, 44(2), 92-99. doi:10.1363/4409212 Arie, S. (2005). Crusading for change. BMJ: British Medical Journal (International Edition), 330(7497), 926. Chamberlain College of Nursing. (2013). NR504 Leadership and nursing practice: role development: Week 4 lesson. St. Louis, MO: Online Publication. Kinsman, J. J., Nakiyingi, J. J., Kamali, A. A., & Whitworth, J. J. (2001). Condom awareness and intended use: gender and religious contrasts among school pupils in rural Masaka, Uganda. AIDS Care, 13(2), 215-220. doi:10.1080/09540120020027387 Porter-O’Grady, T., & Malloch, K. (2011). Quantum leadership: Advancing innovation, transforming health care (3rd ed.). S udbury, MA: Jones & Bartlett. Starkman, N., & Rajani, N. (2002). The Case for Comprehensive Sex Education. AIDS Patient Care & Stds, 16(7), 313-318. doi:10.1089/108729102320231144
Thursday, January 2, 2020
Company Compare Globally Trending Companies - Free Essay Example
Sample details Pages: 3 Words: 948 Downloads: 1 Date added: 2019/10/10 Did you like this example? HM and Uniqlo are two globally trending companies that deals with fashion in clothing (Kennedy, Stoehre, Calderin, 2013). Each of these companies aim to reach the same market as the other but do not use the same strategy as the other in marketing their product. The Uniqlo Company is Japanese and was begun in 1949. In the year 2005, it was however bought by another company (Karan, 2010). Don’t waste time! Our writers will create an original "Company Compare : Globally Trending Companies" essay for you Create order On the other hand, HM is a Swedish company that founded in 1947. This company makes and trades its products under a variety of brand names. For instance, it is the owner of the Monki and weekday brands, among others. The two companies have different business models and approached to which they do their business. HM’s model is founded on the gap’s model. The companies also vary in how they own materials, how they source them, how they manufacture them into a finished product and how they treat the auxiliary trade names. According to the Robecos SAM sustainability industry mover ranking, HM qualified to be ranked at the top and was thus awarded for this. Its awarding was done based on its achievement of high improvement as far as sustainability was concerned. HM has also been included in other records owing to its global performance. These include the Dow Jones sustainability, global compact 100 stock and the FTSE4Good indices. The company has also won various awards, such as the 2016 world’s most ethical company and the PETA Libby awards. Uniqlo has won various awards too. One of these is the business impact of the year award in 2016. This was meant to recognize the company for contributing to enhancing the Chicago magnificent mile. According to the Japanese times, Uniqlo was also awarded for having the best communication strategy within the organization. Between the two companies, HM has the highest number of warehouses (Granger, 2012). Globally, the company has three thousand four hundred and fifty warehouses. In comparison, Uniqlo has only one thousand and four hundred stores. Their venture into the United States is also varied with Uniqlo having the least warehouses in the country. HM uses the designer clothes approach to attract its customers to buy their product. This company, to market its products, has used such brand names as Versace. Another strategy that the company uses is the collaboration with well trending companies in the world of fashion (Baines, Fill, 2014). Uniqlo on the other hand highly localizes its distribution centers in Japan. This company uses the principle of timely presence of product in their stores as a distribution strategy. Production in this company is based on market demand for the product. Dickens (2015) posits that changes in the Japanese fashion is the main determinant of change in the com pany-customer interaction. For this reason, Uniqlo has not had great influence in the western market. With respect to their choices in branding, the companies also have experienced varied responses in the market. HM has purchased and developed brands that are characterized by style and uniqueness (West, Ford, Ibrahim, 2016). These attributes have played a major role for its acceptance in the market. The company also varies its price tag based on the brand. Highly fashionable products are tagged at high prices as compared to the products that are not highly fashionable. For instance, collection of style products are sold at high costs than does the Monki products. The Gap strategy used by Uniqlo is meant to privatize the company’s brands. After production, the company sells its products in highly regulated stores and on online markets. According to Manzenreiter (2013), branding is influenced by the sports trends and this is used by Uniqlo to influence the buyers. The company’s design is however, simple and practical as compared to that of HM. This attribute makes Uniqlo ’s products more appealing to varied populations. According to Vecchi (2016), Production in the HM Company is not internally done but rather the company affiliates with other organizations to meet its objective. The company depends on outsourcing as a strategy to lower its cost of production owing to affordable labor. The company outsources from Asian countries especially those with large populations and high poverty levels (West, Ford, Ibrahim, 2016). For instance, Bangladesh and Cambodia. HM do not own production units but instead collaborates with companies to produce for them. The company has formed partnerships with nine hundred organizations around globe. Most of these organizations who are suppliers are located in the European and Asian countries. The company uses waterways and railways to move its products from the factories to warehouses around the globe. Unlike HM production for Uniqlo is done in its home country. Uniqlo also outsources its laborers from china. The company affiliates with seventy other companies to produc e its products. The major partner of Uniqlo in its business is a Japanese firm known as Kaihara Denim (Russell,  Taylor, 2013). Eziegenfuss (2013) states various attributes of the corporate culture in HM. some of these attributes include believing in people, teamwork, honesty and open- mindedness, being entrepreneurial as well as being cost conscious. According to Davis (2014), the corporate culture at Uniqlo is so specific. The staff have several things to put in their mind while working there. One of these is the need for extensive training. They must be the best. Another strategy that constitutes the culture is teamwork. The staff do not work individually but in teams which lead to specialization. Smiling is what keeps customers to visit the stores again. For this reason, the company does everything in its ability to keep the staff comfortable.
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